U.S. patent application number 17/444610 was filed with the patent office on 2022-06-30 for breathing assistance apparatus.
The applicant listed for this patent is Fisher & Paykel Healthcare Limited. Invention is credited to Silvan Terence BUTLER, Benjamin Wilson CASSE, Tak Ming CHUNG, Sergiu Constantin FILIP, Venkata Subbarao POTHARAJU, Andrew Paul Maxwell SALMON, Jonathan McLean THOMSON, Alex YOUNG.
Application Number | 20220203062 17/444610 |
Document ID | / |
Family ID | 1000006196404 |
Filed Date | 2022-06-30 |
United States Patent
Application |
20220203062 |
Kind Code |
A1 |
YOUNG; Alex ; et
al. |
June 30, 2022 |
BREATHING ASSISTANCE APPARATUS
Abstract
A device for use as part of a breathing assistance system for
providing gases to a user. The device may include a fan, an
enclosure for receiving a humidification chamber or both. A user
interface of the device can indicate the operating mode of the
device, whether a peripheral device is connected and whether a
gases conduit is correctly connected to the outlet of the device. A
controller in the device may hide or block options from the display
of the user interface and may also initiate a power save mode when
the device is powered by a battery.
Inventors: |
YOUNG; Alex; (Auckland,
NZ) ; BUTLER; Silvan Terence; (Auckland, NZ) ;
THOMSON; Jonathan McLean; (Auckland, NZ) ; SALMON;
Andrew Paul Maxwell; (Auckland, NZ) ; POTHARAJU;
Venkata Subbarao; (Auckland, NZ) ; CASSE; Benjamin
Wilson; (Auckland, NZ) ; CHUNG; Tak Ming;
(Auckland, NZ) ; FILIP; Sergiu Constantin;
(Auckland, NZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Fisher & Paykel Healthcare Limited |
Auckland |
|
NZ |
|
|
Family ID: |
1000006196404 |
Appl. No.: |
17/444610 |
Filed: |
August 6, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13500628 |
Jun 26, 2012 |
11110246 |
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PCT/NZ2010/000201 |
Oct 8, 2010 |
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17444610 |
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61267270 |
Dec 7, 2009 |
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61250186 |
Oct 9, 2009 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 16/0069 20140204;
A61M 16/0816 20130101; A61M 16/161 20140204; A61M 16/16 20130101;
A61M 16/109 20140204; A61M 2016/0039 20130101; A61M 2016/0027
20130101; A61M 2205/8206 20130101; A61M 2205/52 20130101; A61M
16/024 20170801; A61M 2205/3653 20130101; A61M 16/1075 20130101;
A61M 2205/502 20130101; A61M 2205/3368 20130101 |
International
Class: |
A61M 16/16 20060101
A61M016/16; A61M 16/10 20060101 A61M016/10; A61M 16/08 20060101
A61M016/08; A61M 16/00 20060101 A61M016/00 |
Claims
1-142. (canceled)
143. An assisted breathing unit configured to provide a flow of
respiratory gases to a user, the unit adapted to receive a
humidifier chamber of the type that in use contains a volume of
water and that has a humidifier gases inlet and a separate
humidifier gases outlet, the assisted breathing unit comprising: an
outer casing that encloses and forms part of the assisted breathing
unit; a patient outlet mounted on the casing and adapted to connect
to a gases conduit whereby gases can pass through and out of the
patient outlet and into the gases conduit; an outlet gases passage
that extends between and fluidly connects the humidifier gases
outlet and the patient outlet whereby heated humidified gases
exiting the humidifier chamber pass into the patient outlet; the
patient outlet rotatable relative to the outer casing to move or
align the patient outlet for storage or use; a connection ring
fitted to and rotatable relative to the outer casing, the patient
outlet removably fitted to the connection ring and, when fitted
together, the connection ring and the patient outlet cannot move
relative to one another; and the connection ring comprising an
electrical connector whereby, with the patient outlet fitted to the
connection ring, the electrical connector is aligned with the
patient outlet so that an electrical and pneumatic connection
between the assisted breathing unit and a connector on an end of
the conduit can be made in one action.
144. The assisted breathing unit of claim 143, wherein the patient
outlet comprises an elbow connector.
145. The assisted breathing unit of claim 144, wherein the patient
outlet comprises a right-angle elbow connector.
146. The assisted breathing unit of claim 145, wherein the patient
outlet comprises an inner portion and an outer portion, the inner
portion is adapted to connect to the casing and receive a stream of
heated and humidified gases from the humidification chamber, and
the outer portion is connectable to the gases conduit, the patient
outlet having an insulating wall formed around and spaced apart
from at least the inner portion whereby an air gap is formed
between the inner end of the gases passage and the insulating
wall.
147. The assisted breathing unit of claim 144, wherein the patient
outlet has a recess formed on an inner side of a bend of the elbow
connector and a second electrical connector is positioned in the
recess and aligned parallel to an outer portion of the elbow
connector whereby electrical and pneumatic connection can be made
with the gases conduit in one action.
148. The assisted breathing unit of claim 147, wherein the outlet
gases passage is separate from the casing whereby the outlet gases
passage can be removed from the casing and replaced.
149. The assisted breathing unit of claim 148, wherein the outlet
gases passage comprises an overall form of a funnel, an inner
portion of the outlet gases passage forming a mouth of the funnel
and an outer portion of the outlet gases passage forming a stem of
the funnel.
150. The assisted breathing unit of claim 149, wherein the mouth is
rectangular.
151. The assisted breathing unit of claim 149, wherein the mouth is
surrounded by a flange.
152. The assisted breathing unit of claim 149, wherein at least a
portion of the stem is wider than a remainder of the stem to
provide a rim to seal against a surface of the patient outlet.
153. The assisted breathing unit of claim 152, wherein the rim
comprises a barbed appearance in cross-section.
154. The assisted breathing unit of claim 148, wherein an outer end
of the outlet gases passage is received in the patient outlet to
form a seal with an inner surface of the patient outlet.
155. The assisted breathing unit of claim 148 further comprising a
removable seal that forms the outlet gases passage, the removable
seal sealing between the humidifier gases outlet and the patient
outlet.
156. The assisted breathing unit of claim 155, wherein the
removable seal is formed from a flexible material.
157. The assisted breathing unit of claim 148 further comprising an
enclosure adapted to receive the humidifier chamber, the enclosure
comprising an inlet port capable of being aligned with the
humidifier gases inlet and at least part of the outlet gases
passage accessible from within the enclosure whereby a user can
remove and replace the outlet gases passage.
158. The assisted breathing unit of claim 148, wherein the patient
outlet has an inner portion and an outer portion, the inner portion
connectable to the connection ring to receive a stream of heated
and humidified gases from the humidification chamber, the outer
portion being connectable to a gases conduit, the patient outlet
comprising an insulating wall formed around and spaced apart from
at least the inner portion whereby an air gap is formed between the
inner portion and the insulating wall, the air gap being closed to
atmosphere by the connection ring when the patient outlet is
connected to the connection ring.
159. The assisted breathing unit of claim 148 further comprising a
fan unit contained within the outer casing and an inlet vent or
inlet port through which gases can enter the gases modification
unit, the fan unit capable of receiving the gases entering through
the inlet vent or inlet port and capable of providing a pressurized
gases stream to the humidifier gases inlet.
160. The assisted breathing unit of claim 159 further comprising a
heater located in the enclosure, the heater capable of contacting
the humidification chamber to heat the volume of water.
161. The assisted breathing unit of claim 148 further comprising a
nasal canula, the nasal canula being connectable to the gases
conduit.
162. An assisted breathing unit for providing a flow of respiratory
gases to a user, the unit adapted to receive a humidifier chamber
having a humidifier gases inlet and a humidifier gases outlet, the
assisted breathing unit comprising: an outer casing comprising a
wall; a connection ring rotatable relative to the wall of the outer
casing, an inlet aperture of the outlet gases passage fluidly
connectable to the humidifier gases outlet so that humidified gases
exiting the humidifier chamber pass through the outlet gases
passage for delivery to a patient.
163. The assisted breathing unit of claim 162, wherein the gases
outlet passage is non-rotatable relative to the wall of the outer
case.
164. The assisted breathing unit of claim 163, wherein the outlet
gases passage is removable from the assisted breathing unit.
165. The assisted breathing unit of claim 164, wherein the outlet
gases passage is fitted to the assisted breathing unit by being
pressed through the connection ring in the wall of the outer
casing.
166. The assisted breathing unit of claim 165 further comprising a
compartment that receives the humidification chamber, an inner
portion of the outlet gases passage includes a flange, the flange
comprises ridges that engage with complementary sockets or slots in
the compartment to hold the outlet gases passage in position.
167. The assisted breathing unit of claim 166, wherein at least
part of the inner portion of the outlet gases passage is curved so
as to fit flush against a curved wall of the compartment.
168. The assisted breathing unit of claim 167, wherein the
connection ring is located in a rear wall of the assisted breathing
unit.
169. The assisted breathing unit of claim 168, wherein the
connection ring is non-removable from the outer casing.
170. The assisted breathing unit of claim 169, wherein the
connection ring comprises a flange and an engaging mechanism is
interposed between the outer casing and the flange of the
connection ring such that the connection ring is non-removable from
the outer casing.
171. The assisted breathing unit of claim 170, wherein the engaging
mechanism is a circlip.
172. The assisted breathing unit of claim 170, wherein the
connection ring is rigid.
173. The assisted breathing unit of claim 172, wherein at least the
inlet aperture of the outlet gases passage is formed from a soft
sealing material.
174. The assisted breathing unit of claim 173, wherein the soft
sealing material is a silicone rubber.
175. The assisted breathing unit of claim 173, wherein an inner
portion of the outlet gases passage forms a mouth portion and an
outer portion of the outlet gases passage forms a stem portion, the
mouth portion being wider than the stem portion.
176. The assisted breathing unit of claim 175, wherein the
connection ring connects to an elbow connector such that the elbow
connector and the connection ring do not move relative to each
other.
177. The assisted breathing unit of claim 176, wherein the
connection ring comprises an electrical connector, the electrical
connector on the connection ring comprising a protrusion configured
to fit into an indent or recess in an inside corner of the elbow
connector.
178. The assisted breathing unit of claim 177, wherein the
connection ring fits over and around an inner end of the elbow
connector.
179. The assisted breathing unit of claim 177, wherein an outlet
end of the outlet gases passage fits into an inner end of the elbow
connector.
180. The assisted breathing unit of claim 179, wherein a seal is
formed between the outlet end of the outlet gases passage and the
inner end of the elbow connector.
181. The assisted breathing unit of claim 180, wherein the
connection ring comprises an inside surface, the inside surface of
the connection ring and the inner end of the elbow connector
comprise complementary slots and ridges for removable connection to
each other.
182. The assisted breathing unit of claim 181, wherein the elbow
connector can be removed by pulling outwardly away from the
assisted breathing unit.
183. The assisted breathing unit of claim 182, wherein the assisted
breathing unit is a continuous positive airway pressure
machine.
184. The assisted breathing unit of claim 182 further comprising a
humidifier chamber.
185. The assisted breathing unit of claim 182 further comprising a
nasal canula.
Description
INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS
[0001] Any and all applications for which a foreign or domestic
priority claim is identified in the Application Data Sheet as filed
with the present application are hereby incorporated by reference
under 37 CFR 1.57.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention generally relates to a gases supply
and gases humidification apparatus, particularly but not solely for
providing respiratory assistance to patients or users who require a
supply of humidified gas at positive pressure for the treatment of
diseases such as Obstructive Sleep Apnea (OSA), snoring, or Chronic
Obstructive Pulmonary Disease (COPD) and the like. More
particularly, the present invention relates to a gases supply
apparatus which has an integral humidifier chamber, so as to form a
combined assisted breathing unit and humidifier.
Description of the Related Art
[0003] Devices or systems for providing a humidified gases flow to
a patient for therapeutic purposes are available. Systems for
providing therapy of this type, for example CPAP therapy, have a
structure where gases at a required pressure are delivered from an
assisted breathing unit or blower unit to a humidifier chamber
downstream from the blower. As the gases pass through the
humidifier chamber, they become saturated with water vapour. A
flexible tubular gases conduit delivers the gases to a user or
patient downstream from the humidifier chamber.
[0004] Humidified gases can be delivered from a modular system that
has been assembled from separate units (i.e., a system where the
humidifier chamber/heater and the breathing unit/blower are
separate items) that are connected in series via conduits. An
example of a system of this type is shown in FIG. 1. However, it is
becoming more common for integrated blower/humidifier systems to be
used. FIG. 2 shows an integrated blower/humidifier system.
[0005] An integrated system generally consists of a main blower or
assisted breathing unit that provides a pressurized gas flow and a
humidifier unit that mates with or is otherwise rigidly connected
to the main blower unit. The mating occurs, for example, by a slide
on or push connection so that the humidifier is held firmly in
place on the main blower unit. An example of a system of this type
is the Fisher and Paykel Healthcare `slide-on` water chamber system
shown and described in U.S. Pat. No. 7,111,624.
[0006] A general advantage of integrated devices is that they are
more compact and discrete than a modular breathing circuit that has
been assembled from separate units. A compact and discrete unit is
particularly advantageous for home-use units, which are used where
bedside space is limited and which may be transported and set up by
a user elsewhere (e.g., if staying overnight away from home). The
reduced footprint of an integrated unit tends to be less than
modular units, which allows placement on a bedside stand or the
like.
[0007] It is becoming more common for these types of devices to
include a removable data storage device for storing data relating
to, for example, use or compliance. The stored data then can be
transported to another location via the removable data device for
analysis or the like. Another advantage of removable data storage
devices is that they can be used to provide set up parameters to a
device, which parameters can be stored on the removable data
device. Once the removable data device is connected to the
breathing assistance unit, the set-up data can be downloaded into
the memory of a controller on the breathing assistance unit. The
set up parameters can be general parameters or the set up
parameters can be tailored to an individual user. One problem with
removably data storage devices is that they easily can be connected
improperly or they easily can become at least partly disconnected
during use. This improper connection or disconnection can occur in
a manner that is not easily apparent to a user at first glance or
that is not immediately or easily visually apparent.
[0008] Another problem with breathing assistance units of the type
described above can occur with a connection between the static or
bedside elements (e.g., the connection between the blower unit and
the humidifier chamber) and the gases transportation pathway (e.g.,
a breathing conduit or hose) that connects between the static
elements and a user interface. These items generally are formed in
such a manner that the hose can be connected and disconnected
multiple times for replacement or cleaning, for example.
[0009] Also, with some devices, the connection between the gases
transportation pathway and the blower/humidifier unit requires an
electrical connection to be made as well as a pneumatic connection.
The wall or walls of some modern breathing conduits are integrally
heated to reduce the likelihood of condensation, which is referred
to as rain-out. The heating requires heater wires or heater
elements in or on the conduit. The heating elements require power.
There may also be sensors in the conduit that require an electrical
connection to provide power and to provide a data transmission
path. Incorrect connection or reconnection of the hose to the gases
source units can cause pneumatic leaks, for example, or, if the
system is of the type that has a pneumatic connection and an
electrical connection, the necessary electrical contact can be
intermittent or non-existent following connection or
reconnection.
[0010] The use of a breathing assistance apparatus can be
irritating to a user for a number of reasons: they can find
prolonged wearing an interface uncomfortable or they (or their
partner) can be disturbed by the operating noises of the apparatus.
Such operating noises can include, for example, air escaping from
an end of the hose or a relatively loud hissing noise made by the
interface. There may also be induction noise as air is sucked into
the system by the fan and the fan itself can be noisy when running.
A major design consideration in domestic breathing assistance
systems is minimizing the operating noise of the apparatus.
[0011] As breathing assistance apparatuses grow more complex and
sophisticated, the control options have also increased in order to
adjust output to produce the most effective therapy regime. Many
efforts have been made to automate the operation of these devices.
Accordingly, a great deal of the adjustment occurs automatically
and `behind-the-scenes` from the point of view of a user. However,
a clinician or other health professional still will require a
certain amount of manual control over an apparatus. For example,
the clinician or other health profession will want to make initial
set-up adjustments for a user or will want to tweak or adjust
treatment parameters during regular check-ups. A clinician or other
health professional will be trained in the operation of the
machine, and due to this training, their professional background
and their familiarity with types of breathing assistance apparatus,
they will be comfortable with a greater degree of sophistication in
control parameters and control displays. In contrast, the end user
does not require this degree of control sophistication, and can
easily become confused or overloaded if presented with too many
options for adjusting or controlling the output.
[0012] Furthermore, some users travel extensively and regularly
spend one or more consecutive nights away from home on business or
pleasure. When traveling, a user may not have access to a mains
power supply. For example, the user may need to sleep in their
vehicle. In order to service this sector of the market, there are
breathing assistance machines on the market that include an
integral power supply or battery. Battery technology recently has
developed to the point where batteries are small enough, light
enough and powerful enough to be practical for this use. However,
in normal operating mode, breathing assistance systems can use a
large amount of power over an extended period, such as when running
at full power for a full eight-hour sleep period. This sustained
demand can easily drain batteries over the course of one or two
nights.
[0013] Improved breathing assistance apparatuses that assist in
overcoming one or more of the abovementioned disadvantages or that
at least provide the public or industry with a useful choice are
desired.
[0014] In this specification where reference has been made to
patent specifications, other external documents, or other sources
of information, such reference generally is for the purpose of
providing a context for discussing certain features of the
invention. Unless specifically stated otherwise, reference to such
external documents is not to be construed as an admission that such
documents, or such sources of information, in any jurisdiction, are
prior art, or form part of the common general knowledge in the
art.
BRIEF SUMMARY OF THE INVENTION
[0015] In some embodiments, the invention may include a blower unit
for use as part of a breathing assistance system for providing
gases to a user at a positive pressure for therapeutic purposes,
comprising: an outer casing, which encloses and forms part of said
blower unit, said outer casing having an inlet vent or inlet port
through which gases can enter said casing in use, and an outlet
port, said inlet port and said outlet port connected by a gases
path within said casing, a fan unit contained within said casing
and located in said gases path, said fan unit adapted to receive
said gases entering through said inlet vent and provide a
pressurized gases stream to said outlet port, electronic circuitry
enclosed within said casing, said electronic circuitry adapted to
provide control signals to control the output or outputs of at
least said blower unit, said blower unit further comprising a
visual indicator adapted to indicate that the blower unit is in an
operating mode.
[0016] The blower unit can further comprises a user display adapted
to display information relating to the output or outputs of at
least said blower, said visual indicator being part of said user
display.
[0017] Alternatively, said visual indicator can be located on said
casing and separate from said user display.
[0018] The visual indicator may be an LED.
[0019] The electronic circuitry may control the fan unit in
multiple modes, including a plurality of operating modes in which
the fan unit will supply gases at a positive therapeutic pressure,
and at least one mode where the fan unit will not supply gases at a
positive therapeutic pressure, and activates the same visual
indicator in respect of all of the plurality of operating modes and
does not activate the visual indicator in respect of other
modes.
[0020] In other embodiments, the invention may include a gases
modification unit for use as part of a breathing assistance system
for providing gases to a user for therapeutic purposes, comprising:
an outer casing having an inlet vent or inlet port through which
gases can enter said casing in use, and an outlet port, said inlet
port and said outlet port connected by a gases path within said
casing, electronic circuitry enclosed within said casing, said
electronic circuitry adapted to provide control signals to control
the modification of properties of gases passing along the gases
path, said gases modification unit further comprising a connection
display which is adapted to indicate to a user that a removable
peripheral device is correctly connected to said blower unit in
use.
[0021] The gases modification unit may further include a fan unit
contained within said casing and located in said gases path. The
fan unit may be adapted to receive said gases entering through said
inlet vent and provide a pressurized gases stream to said outlet
port.
[0022] The casing may have a slot or port on or within said casing
and accessible from outside said casing, adapted to allow the
connection of a removable memory device to said gases modification
unit.
[0023] The connection display may be an LED offset from said slot
or port.
[0024] The gases modification unit may further comprise a user
display adapted to display information relating to operation of the
gases modification unit and the connection display may be
incorporated as part of said user display.
[0025] In other embodiments, the invention may include a gases
modification unit and removable memory device for use as part of a
breathing assistance system for providing gases to a user for
therapeutic purposes, said unit comprising: an outer casing, having
an inlet vent or inlet port through which gases can enter said
casing in use, and an outlet port, said inlet port and said outlet
port connected by a gases path within said casing, electronic
circuitry enclosed within said casing, said electronic circuitry
adapted to provide control signals to control the modification of
properties of gases passing along the gases path, the outer casing
further comprising a slot or port on or within said casing and
accessible from outside said casing, said slot and a removable
memory device mutually adapted to allow the connection of said
removable memory device to said blower unit in such a manner that
when correctly connected, at least part of said removable memory
device protrudes from said casing, said removable memory device
further having a visual indicator on the outside surface, said
visual indicator aligning with the edge of said slot when said
removable memory device is correctly connected to said blower
unit.
[0026] The visual indicator may be a line or ridge on the removable
memory device. The gases modification unit may include a fan unit
contained within said casing and located in said gases path. The
fan unit may be adapted to receive said gases entering through said
inlet vent and provide a pressurized gases stream to said outlet
port.
[0027] In other embodiments, the invention may include a gases
modification unit for use as part of a breathing assistance system
for providing heated humidified gases to a user at a positive
pressure for therapeutic purposes, comprising: an outer casing
having an inlet vent or inlet port through which gases can enter
said casing in use, and an outlet port adapted for connection to a
gases conduit in use so that gases can pass out of said outlet port
and into said conduit, said inlet port and said outlet port
connected by a gases path within said casing, electronic circuitry
enclosed within said casing, said electronic circuitry adapted to
provide control signals to control the modification of properties
of gases passing along the gases path, said gases modification unit
further comprising a conduit connection display which is adapted to
indicate to a user that said conduit is correctly connected to said
outlet port.
[0028] The gases modification unit may include a fan unit contained
within said casing and located in said gases path. The fan unit may
be adapted to receive said gases entering through said inlet vent
and provide a pressurized gases stream to said outlet port. The LED
may be located on said casing at or close to said outlet port.
[0029] The gases modification unit may further comprise a user
display adapted to display information relating to operation of the
gases modification unit and the conduit connection display may be
incorporated as part of said user display.
[0030] In other embodiments, the invention may include a gases
modification unit for use as part of a breathing assistance system
for providing gases to a user at a positive pressure for
therapeutic purposes, comprising: an outer casing having an inlet
vent or inlet port through which gases can enter said casing in
use, and an outlet port adapted for connection to a gases conduit
in use so that gases can pass out of said outlet port and into said
conduit, said inlet port and said outlet port connected by a gases
path within said casing, electronic circuitry enclosed within said
casing, said electronic circuitry adapted to provide control
signals to control modification of properties of the gases passing
through the gases path, a set of user controls adapted to allow a
user to adjust operating parameters of the electronic circuitry, a
user display, adapted to display a control menu which has a number
of control and display options, said user controls manipulable to
hide or block at least one and preferably a plurality of said
control and display options, and once hidden, said user controls
manipulable to unhide or unblock said control and display
options.
[0031] Once said at least one of said control and display options
is blocked, said user controls may be manipulable to hide or block
further one or ones of said control and display options, and
further manipulable to unhide or unblock said hidden one or ones of
said control and display options.
[0032] The electronic circuitry may have a password-protection
routine and the user controls require entry of a password before
allowing a user to hide and unhide at least some of said control
and display options.
[0033] The user controls may have a keying mechanism adapted to
allow a user to hide and unhide at least some of said control and
display options.
[0034] The gases modification unit may include a fan unit contained
within said casing and located in said gases path, said fan unit
adapted to receive said gases entering through said inlet vent and
provide a pressurized gases stream to said outlet port.
[0035] In other embodiments, the invention may include a blower
unit for use as part of a breathing assistance system for providing
gases to a user at a positive pressure for therapeutic purposes,
comprising: an outer casing, which encloses and forms part of said
blower unit, said outer casing having an inlet vent or inlet port
through which gases can enter said casing in use, and an outlet
port adapted for connection to a gases conduit in use so that gases
can pass out of said outlet port and into said conduit, said inlet
port and said outlet port connected by a gases path within said
casing, a fan unit contained within said casing and located in said
gases path, said fan unit adapted to receive said gases entering
through said inlet vent and provide a pressurized gases stream to
said outlet port, electronic circuitry enclosed within said casing,
said electronic circuitry adapted to provide control signals to
control the output or outputs of at least said blower unit, an
internal power source contained within said casing and adapted to
provide power to at least said fan unit and said electronic
circuitry, said blower unit further adapted to connect to a mains
supply to receive power for at least said fan unit and said
electronic circuitry, in use, said blower unit drawing power from
said mains supply by default if connected to said mains supply, and
otherwise drawing power from said internal power source, the
electronic circuitry including a power saving mode for operating
the blower where work is done at a maximum power rate below the
rate at which said blower unit draws power when connected to said
mains supply.
[0036] The electronic circuitry may automatically switches to said
power-saving mode when said blower unit is drawing power from said
internal power source.
[0037] Alternatively, the blower unit may further comprise user
controls adapted to allow a user to switch said electronic
circuitry between a normal operating mode where full power is
available, and said power-saving mode.
[0038] In some embodiments, when in said power saving mode, said
maximum power rate is between 50 W and 100 W, or approximately 75
W.
[0039] In other embodiments, the invention may include a blower
unit for use as part of a breathing assistance system for providing
gases to a user at a positive pressure for therapeutic purposes,
comprising: an outer casing, which encloses and forms part of said
blower unit, said outer casing having an inlet vent or inlet port
through which gases can enter said casing in use, and an outlet
port adapted for connection to a gases conduit in use so that gases
can pass out of said outlet port and into said conduit, said inlet
port and said outlet port connected by a gases path within said
casing, a fan unit contained within said casing and located in said
gases path, said fan unit adapted to receive said gases entering
through said inlet vent and provide a pressurized gases stream to
said outlet port, electronic circuitry enclosed within said casing,
said electronic circuitry adapted to provide control signals to
control the output or outputs of at least said blower unit, said
blower unit further adapted to connect to an external power supply
to receive power for at least said fan unit and said electronic
circuitry, operate in a standard mode when connected to an AC mains
power source, said electronic circuitry having a power saving mode
where work is done at a maximum power rate below the rate at which
said blower unit draws power when operating in said standard mode,
said electronic circuitry adapted to detect when said blower unit
is connected to a synthesized mains AC power supply. The electronic
circuitry may be adapted to detect the frequency of said
synthesized mains AC power supply, said electronic circuitry
automatically switching to said power-saving mode when said
frequency is above 50 Hz.
[0040] Alternatively, or as well, said electronic circuitry may be
adapted to detect the frequency of said synthesized mains AC power
supply, said electronic circuitry automatically switching said to
said power-saving mode when said frequency is above 60Hz.
[0041] Alternatively, or as well, said electronic circuitry may be
adapted to detect a secondary signal superimposed over the power
supply signal, and to automatically switch to said power-saving
mode on receipt of said secondary signal.
[0042] Alternatively, or as well, the blower unit may include a
remote transmission detector connected to said electronic
circuitry, said detector adapted to receive a transmitted signal
and pass said signal to said electronic circuitry, said electronic
circuitry switching to said power-saving mode in response to
receiving a signal indicating that said blower unit is connected to
a synthesized power supply.
[0043] In some embodiments, the blower unit may include user
controls adapted to allow a user to manually switch said blower
unit between said standard operating mode, and said power-saving
mode.
[0044] In some embodiments, the power saving mode, said maximum
power rate is between 50 W and 100 W, or about 75 W.
[0045] In other embodiments, the invention may include a blower
unit for use as part of a breathing assistance system for providing
gases to a user at a positive pressure for therapeutic purposes,
comprising: an outer casing, which encloses and forms part of said
blower unit, said outer casing having an inlet vent or inlet port
through which gases can enter said casing in use, and an outlet
port adapted for connection to a gases conduit in use so that gases
can pass out of said outlet port and into said conduit, said inlet
port and said outlet port connected by a gases path within said
casing, a fan unit contained within said casing and located in said
gases path, said fan unit adapted to receive said gases entering
through said inlet vent and provide a pressurized gases stream to
said outlet port, electronic circuitry enclosed within said casing,
said electronic circuitry adapted to provide control signals to
control the output or outputs of at least said blower unit, an
internal power source contained within said casing and adapted to
provide power to at least said fan unit and said electronic
circuitry, said blower unit further adapted to connect to a mains
supply to receive power for at least said fan unit and said
electronic circuitry, in use, said blower unit drawing power from
said mains supply by default if connected to said mains supply, and
otherwise drawing power from said internal power source, said
electronic circuitry having a power saving mode where work is done
at a maximum power rate below the rate at which said blower unit
draws power when connected to said mains supply, said blower unit
further comprising user controls adapted to allow a user to switch
said electronic circuitry between a normal operating mode where
full power is available, and said power-saving mode.
[0046] The electronic circuitry may automatically switch to said
power-saving mode when said blower is drawing power from said
internal power source, said user controls further adapted to allow
a user to switch said blower unit from said power saving mode to
said normal operating mode manually when said blower unit is
drawing power from said internal power source.
[0047] In some embodiments, when said blower is in said power
saving mode, said maximum power rate is between 50 W and 100 W, or
about 75 W
[0048] In other embodiments, the invention may include a gases
modification unit for providing heated humidified gases to a user,
said system using a humidifier chamber of the type which in use
contains a volume of water and which has a humidifier gases inlet
and a separate humidifier gases outlet, said unit comprising: an
outer casing, which encloses and forms part of said unit, said
outer casing having an inlet vent or inlet port through which gases
can enter said casing in use, a patient outlet mounted on said
casing and adapted for connection to a gases conduit in use so that
gases can pass out of said patient outlet and into said conduit, an
enclosure adapted to in use receive said humidifier chamber, said
enclosure having an inlet port adapted to in use align with said
humidifier gases inlet, an outlet gases passage, in use said outlet
gases passage running between and gaseously connecting said
humidifier gases outlet and said patient outlet so that heated
humidified gases exiting said humidifier chamber pass into said
patient outlet, said outlet gases passage formed as a separate item
to said casing and said enclosure, at least part of said outlet
gases passage accessible from within said enclosure and adapted to
allow a user to remove and replace said outlet gases passage
easily. The outlet gases passage may have the overall form of a
funnel, an inner portion of said outlet gases passage forming a
mouth of said funnel, an outer portion of said outlet gases passage
forming a stem of said funnel. The mouth of the funnel may be
substantially rectangular.
[0049] The mouth of the funnel may be surrounded by a flange. At
least a portion of said stem of the funnel may be wider than a
remainder of the stem. The wider portion may be formed at the outer
rim of said stem, said rim having a barbed appearance in
cross-section.
[0050] The gases modification unit may include a fan unit contained
within said casing, said fan unit adapted to receive said gases
entering through said inlet vent and provide a pressurized gases
stream to said enclosure inlet port.
[0051] The gases modification unit may include a heater located in
said enclosure, in use said heater contacting the humidifier
chamber to heat said volume of water.
[0052] In other embodiments, the invention may include a gases
modification unit for providing heated humidified gases to a user,
said system using a humidifier chamber of the type which in use
contains a volume of water and which has a humidifier gases inlet
and a separate humidifier gases outlet, said blower unit
comprising: an outer casing, which encloses and forms part of said
blower unit, said outer casing having an inlet vent or inlet port
through which gases can enter said casing in use, a patient outlet
mounted on said casing and adapted for connection to a gases
conduit in use so that gases can pass through and out of said
patient outlet and into said conduit, an enclosure adapted to in
use receive said humidifier chamber, said enclosure having an inlet
port adapted to in use align with said humidifier gases inlet, an
outlet gases passage, in use said outlet gases passage running
between and gaseously connecting said humidifier gases outlet and
said patient outlet so that heated humidified gases exiting said
humidifier chamber pass into said patient outlet, said patient
outlet removably mounted on said casing.
[0053] The patient outlet may be an elbow connector.
[0054] In some embodiments, the patient outlet may be a
substantially right-angled elbow connector.
[0055] Alternatively, or as well, the patient outlet may be a gases
passage having an inner end and an outer end, said inner end
adapted to connect to said casing and receive a stream of heated,
humidified gases from said integrated blower/humidification system,
said outer end adapted to in use connect to a gases conduit, said
patient outlet may also have an insulating wall formed around and
spaced from at least said inner end so that an airgap is formed
between said inner end of said gases passage and said insulating
wall.
[0056] The patient outlet may also have a recess formed on the
inner side of the bend of the elbow.
[0057] The gases modification unit may include a fan unit contained
within said casing, said fan unit adapted to receive said gases
entering through said inlet vent and provide a pressurized gases
stream to said enclosure inlet port.
[0058] The gases modification unit may include a heater located in
said compartment, in use said heater contacting said humidification
chamber to heat said volume of water.
[0059] In other embodiments, the invention may include a patient
connector for use as part of a gases modification unit for
providing heated humidified gases to a user, said blower unit of
the type that has an outer casing, said patient connector
comprising: a gases passage having an inner end and an outer end,
said inner end adapted to connect to said casing and receive a
stream of heated, humidified gases from said gases modification
unit, said outer end adapted to in use connect to a gases conduit,
an insulating wall, formed around and spaced from at least said
inner end so that an insulating space is formed between said inner
end of said gases passage and said insulating wall.
[0060] The patient outlet may be an elbow connector. In some
embodiment, the patient outlet may be a substantially right-angled
elbow connector.
[0061] The patient outlet may also have a recess formed on the
inner side of the bend of the elbow.
[0062] In other embodiments, the invention may include a humidifier
unit for use with a system for providing humidified gases to a
user, comprising: a humidifier chamber adapted to contain a volume
of water, said humidifier chamber further having a gases inlet port
and a gases outlet port, an elongate inlet passage extending into
said humidifier chamber from said gases inlet port, said inlet
passage having at least one primary gases inlet aperture, at or
towards that end of said inlet passage furthest from said gases
inlet, to allow gases to pass out of said inlet passage and into
said humidifier chamber, an elongate exit passage extending into
said humidifier chamber from said gases outlet port, said passage
having at least one and preferably two primary gases exit
apertures, at or towards that end of said exit passage furthest
from said gases outlet, to allow gases to pass out of said
humidifier chamber and into said exit passage, said primary gases
inlet aperture formed in the side of said inlet passage.
[0063] The primary gases exit aperture or apertures may be formed
in the side or sides of said exit passage.
[0064] The elongate inlet passage may have an inlet recess formed
in the lower part of said inlet passage, and at least one and
preferably a plurality of secondary inlet apertures formed in said
recess to allow gases to pass out of said inlet passage and into
said humidifier chamber.
[0065] The elongate exit passage may have an exit recess formed in
the lower part of said inlet passage, and at least one and
preferably a plurality of secondary exit apertures formed in said
recess to allow gases to pass out of said humidifier chamber and
into said exit passage.
[0066] In some embodiment, the exit passage and said entry passage
may be aligned at an angle to one another.
[0067] The primary gases inlet aperture may be formed in that side
of said inlet passage which is furthest from said exit passage.
[0068] The chamber may have at least one and preferably a plurality
of buttress ribs spanning between the wall of said humidifier
chamber and a position at or close to the inner end of at least one
of said exit passage or said entry passage. The buttress rib or
ribs may be located at or towards the top of said chamber.
[0069] In some embodiments, the chamber may appear substantially
circular in plan view.
[0070] In some embodiments, the exit passage, the entry passage and
said buttress ribs may be arranged radially and connect at the
centre of said chamber, the inner ends of said exit passage and
said entry passage blocked by a dividing wall.
[0071] The chamber may have a baffle which extends downwards
between said entry passage and said exit passage.
[0072] The humidifier chamber may be open-topped, and said
humidifier unit also have a separate lid unit, adapted to close and
seal said open top of said humidifier chamber in use.
[0073] The lid unit may comprise a separate lid portion and a
handle portion, said handle portion releasably connecting to said
lid portion in such a manner that said handle can freely rotate
while connected to said lid portion, said lid portion adapted to
seal on said open top of said humidifier chamber.
[0074] In some embodiments, the inlet passage and said exit passage
are structurally connected but fluidically disconnected. In other
embodiments, the invention may include a humidifier unit for use
with a system for providing humidified gases to a user, comprising:
a humidifier chamber adapted to contain a volume of water, said
humidifier chamber further having a gases inlet port and a gases
outlet port, an elongate inlet passage extending into said
humidifier chamber from said gases inlet port, said inlet passage
having at least one primary gases inlet aperture, at or towards
that end of said inlet passage furthest from said gases inlet, to
allow gases to pass out of said inlet passage and into said
humidifier chamber, an elongate exit passage extending into said
humidifier chamber from said gases outlet port, said passage having
at least one and preferably two primary gases exit apertures, at or
towards that end of said exit passage furthest from said gases
outlet, to allow gases to pass out of said humidifier chamber and
into said exit passage, at least one of said primary gases exit
apertures formed in the side of said exit passage.
[0075] The primary gases inlet aperture may be formed in the side
of said inlet passage.
[0076] The elongate inlet passage may have an inlet recess formed
in the lower part of said inlet passage, and at least one and
preferably a plurality of secondary inlet apertures formed in said
recess to allow gases to pass out of said inlet passage and into
said humidifier chamber.
[0077] The elongate exit passage may have an exit recess formed in
the lower part of said exit passage, and at least one and
preferably a plurality of secondary exit apertures formed in said
exit recess to allow gases to pass out of said humidifier chamber
and into said exit passage.
[0078] In some embodiments, the exit passage and said entry passage
may be aligned at an angle to one another.
[0079] The primary gases inlet aperture may be formed in that side
of said inlet passage which is furthest from said exit passage.
[0080] The chamber may have also has at least one and preferably a
plurality of buttress ribs spanning between the wall of said
humidifier chamber and a position at or close to the inner end of
at least one of said exit passage or said entry passage. The
buttress rib or ribs may be located at or towards the top of said
chamber.
[0081] In some embodiments, the chamber may appear substantially
circular in plan view. In some embodiments, the exit passage, said
entry passage and said buttress ribs may be arranged radially and
connect at the centre of said chamber, the inner ends of said exit
passage and said entry passage blocked by a dividing wall.
[0082] The chamber may have a baffle which extends downwards
between said entry passage and said exit passage. The humidifier
chamber may be open-topped, and said humidifier unit may have a
separate lid unit, adapted to close and seal said open top of said
humidifier chamber in use.
[0083] The lid unit may comprise a separate lid portion and a
handle portion, said handle portion releasably connecting to said
lid portion in such a manner that said handle can freely rotate
while connected to said lid portion, said lid portion adapted to
seal on said open top of said humidifier chamber.
[0084] The inlet passage and the exit passage may be structurally
connected but fluidically disconnected.
[0085] In other embodiments, the invention may include a humidifier
unit for use with a system for providing humidified gases to a
user, comprising: a humidifier chamber adapted to contain a volume
of water, said humidifier chamber further having a gases inlet port
and a gases outlet port, an inlet passage extending into said
humidifier chamber from said gases inlet port, an exit passage
extending into said humidifier chamber from said gases outlet port,
at least one of said passages having a recess formed in the lower
part of said passage or passages, at least one and preferably a
plurality of apertures formed in said recess to allow gases to pass
between said passage and said chamber.
[0086] The inlet passage may be an elongate passage extending into
said humidifier chamber from said gases inlet port. The recess may
be formed in said inlet passage. The at least one and preferably a
plurality of apertures may be secondary gases inlet apertures. The
inlet passage may also have at least one primary gases inlet
aperture, at or towards that end of said inlet passage furthest
from said gases inlet, to allow gases to pass out of said inlet
passage and into said humidifier chamber.
[0087] The exit passage may be an elongate exit passage extending
into said humidifier chamber from said gases outlet port. The exit
passage may have at least one and preferably two primary gases exit
apertures, at or towards that end of said exit passage furthest
from said gases outlet, to allow gases to pass out of the
humidifier chamber and into said exit passage.
[0088] The exit passage may be an elongate passage extending into
said humidifier chamber from said gases exit port. An exit recess
may be formed in said exit passage, with said at least one and
preferably a plurality of apertures being secondary gases exit
apertures. The exit passage may also have at least one primary
gases exit aperture, at or towards that end of said exit passage
furthest from said gases exit port, to allow gases to pass out of
said humidifier chamber and into said exit passage. The inlet
passage may be an elongate passage extending into said humidifier
chamber from said gases inlet port. The passage may have at least
one gases inlet aperture, at or towards that end of said inlet
passage furthest from said gases inlet port, to allow gases to pass
into said humidifier chamber from said inlet passage.
[0089] The primary gases inlet aperture may be formed in the side
of said inlet passage.
[0090] The primary gases exit aperture or apertures may be formed
in the side or sides of said exit passage.
[0091] The elongate exit passage may also have an exit recess
formed in the lower part of said exit passage. At least one and
preferably a plurality of secondary exit apertures may be formed in
said exit recess to allow gases to pass out of said humidifier
chamber and into said exit passage.
[0092] The exit passage and the entry passage may be aligned at an
angle to one another.
[0093] The primary gases inlet aperture may be formed in that side
of said inlet passage which is furthest from said exit passage.
[0094] The chamber may also have at least one and preferably a
plurality of buttress ribs spanning between the wall of said
humidifier chamber and a position at or close to the inner end of
at least one of said exit passage or said entry passage. The
buttress rib or ribs may be located at or towards the top of said
chamber.
[0095] In some embodiments, the chamber may be substantially
circular in plan view.
[0096] The exit passage, said entry passage and said buttress ribs
may be arranged radially and connect at the centre of said chamber,
with the inner ends of said exit passage and said entry passage
blocked by a dividing wall.
[0097] The chamber may have a baffle which extends downwards
between said entry passage and said exit passage.
[0098] The humidifier chamber may be open-topped, and the
humidifier unit may have a separate lid unit, adapted to close and
seal said open top of said humidifier chamber in use. The lid unit
may comprise a separate lid portion and a handle portion, said
handle portion releasably connecting to said lid portion in such a
manner that said handle can freely rotate while connected to said
lid portion, said lid portion adapted to seal on said open top of
said humidifier chamber.
[0099] In other embodiments, the invention may include a humidifier
unit for use with a system for providing humidified gases to a
user, comprising: a humidifier chamber adapted to contain a volume
of water, said humidifier chamber further having a gases inlet port
and a gases outlet port, an elongate inlet passage extending into
said humidifier chamber from said gases inlet port, said inlet
passage having at least one gases inlet aperture, at or towards
that end of said inlet passage furthest from said gases inlet, to
allow gases to pass out of said inlet passage and into said
humidifier chamber, an elongate exit passage extending into said
humidifier chamber from said gases outlet port, said passage having
at least one gases exit apertures, at or towards that end of said
exit passage furthest from said gases outlet, to allow gases to
pass out of said humidifier chamber and into said exit passage,
said chamber also has at least one and preferably a plurality of
buttress ribs spanning between the wall of said humidifier chamber
and a position at or close to the inner end of at least one of said
exit passage or said entry passage.
[0100] The buttress rib or ribs may be located at or towards the
top of said chamber.
[0101] In some embodiments, at least one of said passages may have
a recess formed in the lower part of said passage or passages, with
at least one and preferably a plurality of apertures formed in said
recess or recesses to allow gases to pass between said passage and
said chamber.
[0102] The inlet passage may be an elongate passage extending into
said humidifier chamber from said gases inlet port, with said
recess formed in said inlet passage. The at least one aperture may
be secondary gases inlet apertures. The inlet passage may also have
at least one primary gases inlet aperture, at or towards that end
of said inlet passage furthest from said gases inlet, to allow
gases to pass out of said inlet passage and into said humidifier
chamber.
[0103] The exit passage may be an elongate exit passage extending
into said humidifier chamber from said gases outlet port, said
passage having at least one and preferably two primary gases exit
apertures, at or towards that end of said exit passage furthest
from said gases outlet, to allow gases to pass out of said
humidifier chamber and into said exit passage. An exit recess may
be formed in said exit passage, at least one and preferably a
plurality of secondary gases exit apertures formed in said recess,
to allow gases to pass out of said humidifier chamber and into said
exit passage.
[0104] In some embodiments, said primary gases inlet aperture may
be formed in the side of said inlet passage.
[0105] The primary gases exit aperture or apertures may be formed
in the side or sides of said exit passage. The exit passage and
said entry passage may be aligned at an angle to one another. The
primary gases inlet aperture may be formed in that side of said
inlet passage which is furthest from said exit passage.
[0106] In some embodiments, the chamber may appear substantially
circular in plan view. In some embodiments, the chamber further may
have a baffle which extends downwards between said entry passage
and said exit passage.
[0107] In some embodiments, the humidifier chamber may be
open-topped, and said humidifier unit may have a separate lid unit,
adapted to close and seal said open top of said humidifier chamber
in use. The lid unit may comprise a separate lid portion and a
handle portion, said handle portion releasably connecting to said
lid portion in such a manner that said handle can freely rotate
while connected to said lid portion, said lid portion adapted to
seal on said open top of said humidifier chamber.
[0108] In other embodiments, the invention may include a humidifier
unit for use with a system for providing humidified gases to a
user, comprising: a humidifier chamber adapted to contain a volume
of water, an inlet passage having a gases inlet port adapted to
receive gases from a gases source in use, and at least one gases
inlet aperture adapted to allow gases to pass out of said inlet
passage and into said humidifier chamber, an exit passage having a
gases outlet port adapted to allow said heated humidified gases to
exit said chamber, and at least one gases exit aperture adapted to
allow gases to pass out of said humidifier chamber and into said
exit passage, in plan view, said gases inlet aperture and said
gases exit aperture located at or close to the centre of said
chamber, and said gases outlet port and said gases inlet port are
located inside the perimeter of said chamber.
[0109] The gases outlet port and said gases inlet port may be
located at or close to close to the centre of said chamber. The
gases outlet port may be located between said perimeter and said
gases exit aperture, and said gases inlet port may be located
between said perimeter and said at least one gases inlet
aperture.
[0110] In some embodiments, the humidifier unit also has at least
one and preferably a plurality of buttress ribs spanning between
the wall of said humidifier chamber and said inlet passage and said
exit passage, said inlet passage and said exit passage unconnected
to said chamber except via said ribs. The buttress rib or ribs and
said passages are located at or towards the top of said chamber.
The chamber may appear substantially circular in plan view, said
passages extending radially towards the perimeter of said chamber,
said passages structurally connected at the centre of said chamber
but gaseously or fluidically unconnected. The buttress rib or ribs
may extend radially from said passages to the perimeter of
said-chamber. The gases outlet port is aligned substantially
horizontally. Alternatively, gases outlet port may be aligned
facing upwards substantially vertically.
[0111] In some embodiments, the gases inlet port may be aligned
substantially horizontally.
[0112] Alternatively, the gases inlet port may be aligned facing
upwards substantially vertically.
[0113] In some embodiments, the inlet passage may be an elongate
passage having at least one primary gases inlet aperture, at or
towards that end of said inlet passage furthest from said gases
inlet, formed in the side of said inlet passage, to allow gases to
pass out of said inlet passage and into said humidifier
chamber.
[0114] In some embodiment, the exit passage may be an elongate exit
passage having at least one and preferably two primary gases exit
apertures, at or towards that end of said exit passage furthest
from said gases outlet, formed in the side or sides of said exit
passage to allow gases to pass out of said humidifier chamber and
into said exit passage.
[0115] In some embodiments, at least one of said passages may have
a recess formed in the lower part of said passage or passages, at
least one and preferably a plurality of secondary apertures formed
in said recess or recesses to allow gases to pass between said
passage and said chamber.
[0116] In some embodiments, said exit passage and said entry
passage may be aligned at an angle to one another. The primary
gases inlet aperture may be formed in that side of said inlet
passage which is furthest from said exit passage.
[0117] In some embodiments, said chamber may have a baffle which
extends downwards between said entry passage and said exit
passage.
[0118] In some embodiments, said humidifier chamber may be
open-topped, and said humidifier unit may have a separate lid unit,
adapted to close and seal said open top of said humidifier chamber
in use. The lid unit may comprise a separate lid portion and a
handle portion, said handle portion releasably connecting to said
lid portion in such a manner that said handle can freely rotate
while connected to said lid portion, said lid portion adapted to
seal on said open top of said humidifier chamber.
[0119] In other embodiments, the invention may include a gases
modification unit for use as part of a breathing assistance system
for providing gases to a user at a positive pressure for
therapeutic purposes, comprising: an outer casing having an inlet
vent or inlet port through which gases can enter said casing in
use, and an outlet port adapted for connection to a gases conduit
in use so that gases can pass out of said outlet port and into said
conduit, said inlet port and said outlet port connected by a gases
path within said casing, electronic circuitry enclosed within said
casing, said electronic circuitry adapted to provide control
signals to control modification of properties of the gases passing
through the gases path, a set of user controls adapted to allow a
user to adjust operating parameters of the electronic circuitry, a
user display, adapted to display a control menu which has a number
of control and display options, said electronic circuitry adapted
to selectively not respond to manipulations of the user
controls.
[0120] The electronic circuitry may stop responding to
manipulations of the user controls after a predetermined period of
time without manipulation of the controls.
[0121] Alternatively, the electronic circuitry will stop responding
to manipulations of the user controls after a predetermined period
of time without manipulation of the controls, when in one or more
predetermined operating modes.
[0122] Alternatively, or additionally, the electronic circuitry
will stop responding to manipulations of the user controls after a
predetermined period of time without manipulation of the controls,
but will still respond when in one or more predetermined operating
modes.
[0123] In some embodiments, the gases modification unit may include
a fan unit contained within said casing and located in said gases
path, said fan unit adapted to receive said gases entering through
said inlet vent and provide a pressurized gases stream to said
outlet port.
[0124] The term "comprising" as used in this specification means
"consisting at least in part of," that is to say when interpreting
statements in this specification which include that term, the
features, prefaced by that term in each statement, all need to be
present but other features can also be present.
[0125] This invention may also be said broadly to consist in the
parts, elements and features referred to or indicated in the
specification of the application, individually or collectively, and
any or all combinations of any two or more of said parts, elements
or features, and where specific integers are mentioned herein which
have known equivalents in the art to which this invention relates,
such known equivalents are deemed to be incorporated herein as if
individually set forth.
BRIEF DESCRIPTION OF THE DRAWINGS
[0126] These and other features, aspects and advantages of an
improved breathing assistance apparatus will now be described with
reference to the drawings of a preferred embodiment, which
embodiment is intended to illustrate and not to limit the
invention, and in which figures:
[0127] FIG. 1 shows a schematic view of a user receiving humidified
air from a modular breathing assistance apparatus.
[0128] FIG. 2 shows a schematic view of a user receiving humidified
air from an integrated breathing assistance apparatus.
[0129] FIG. 3 shows an embodiment of a blower and humidifier of a
breathing assistance apparatus that is arranged and configured in
accordance with certain features, aspects and advantages of the
present invention. The illustrated apparatus is of the integrated
blower/humidifier type and includes a blower unit that has a
central enclosure that receives a humidifier. The blower unit also
has a front face with a user display panel and user controls.
[0130] FIG. 4 shows a different view of breathing assistance
apparatus of FIG. 3 with detail of a slot that receives a removable
memory device shown and the removable memory device suitable for
use with the integrated blower/humidifier system also shown.
[0131] FIGS. 5a-5e show examples of displays that can be shown on
the user display panel of the blower unit with FIG. 5e showing the
maximum amount of information that can be displayed on the
illustrated user display and FIGS. 5a-d showing displays having
different combinations of the information blocked so that it is not
viewed by a user.
[0132] FIG. 6 shows a rear view of the blower unit with the
humidifier removed to show a removable seal that forms a passage to
a patient outlet or elbow, which passage extends through a rear
wall and an outer casing of the blower unit.
[0133] FIG. 7 shows the same view as FIG. 6 with the outer casing
removed.
[0134] FIG. 8 shows an exploded view of the portion of the blower
unit that forms the enclosure with the removable seal, the patient
outlet and a sealing/connection ring that fits on and around part
of the patient outlet shown.
[0135] FIG. 9 shows a cutaway view of the rear of the blower unit
with detail of the removable seal, the sealing/connection ring, and
the elbow connector or patient outlet also shown.
[0136] FIGS. 10a and 10b show detail of the patient outlet.
[0137] FIGS. 11a and 11b show detail of the removable seal.
[0138] FIG. 12 shows detail of the sealing/connection ring. FIG. 13
shows an exploded view of the blower and humidifier unit of the
breathing assistance apparatus as shown in FIG. 3, wherein the
humidifier unit comprises a humidifier chamber, a separate chamber
lid and a separate handle.
[0139] FIG. 14 shows a perspective view of the humidifier chamber
of FIG. 13 with the humidifier chamber having a substantially
horizontal inlet passage and an exit passage aligned radially and
located towards the top of the chamber.
[0140] FIG. 15 shows the humidifier chamber of FIG. 14, but with a
cap removed above open tops of the inlet and exit passages towards
the centre of the chamber.
[0141] FIG. 16 shows a cutaway view of the chamber of FIG. 15,
along section line A-A in FIG. 15.
DETAILED DESCRIPTION OF THE INVENTION
[0142] A schematic view of a user 3 receiving air from a modular
assisted breathing unit and humidifier system is shown in FIG. 1. A
conduit 41 provides pressurized air from an assisted breathing unit
or blower la to a humidifier chamber 2a. Humidified, heated and
pressurized gases exit the humidifier chamber 2a via a conduit 21,
and are provided to the patient or user 3 via a user interface 4.
The user interface 4 shown in FIG. 1 is a nasal mask, which covers
the nose of the user 3. However, it should be noted that in systems
of these types, a full face mask, nasal cannula, tracheostomy
fitting nasal pillows, oral interface, or any other suitable user
interface could be substituted for the nasal mask shown.
[0143] FIG. 2 shows a schematic view of the user 3 receiving air
from an integrated blower/humidifier unit 5. The system generally
operates in the same manner as the modular system shown in FIG. 1
except that a humidifier chamber 2b has been integrated with a
blower unit lb to form the integrated unit 5. An example of an
integrated unit is described in PCT application WO2008/056993,
which is hereby incorporated by reference in its entirety.
Assisted Breathing Unit
[0144] An improved form of an assisted breathing unit or integrated
unit 6 will now be described with reference to FIGS. 3 and 4.
[0145] The integrated unit 6 comprises two main parts: an assisted
breathing or blower unit 7 and a humidification unit 31. When in
use, the humidification unit 31 generally is enclosed within an
enclosure 42 that is formed in an external casing of the integrated
unit 6. In the illustrated configuration, the top part of the
humidification unit 31 is not enclosed within the enclosure 42.
[0146] The blower unit 7 has an outer shell that generally is a
rectangular block with substantially vertical side and rear walls,
and a front face that is angled slightly rearwards. In the
illustrated embodiment, the walls, base and top surface are all
manufactured and connected as far as possible to minimize the
occurrence of seams. Any necessary seams can be sealed. 1 This
outer shell generally encloses the working parts of the blower unit
7 and forms part of the blower unit 7.
[0147] As shown in FIGS. 3 and 4, a user interface is located on
the lower section of the front face of the illustrated integrated
unit 6 with a control display 9 located directly above the user
interface. The user interface can include a control knob 8. A
patient outlet 25 is shown passing out of the rear wall of the
integrated unit 6. In the illustrated embodiment, in use the free
end of the outlet 25 faces upwards for ease of connection. However,
the patient outlet 25 can be rotated to one side or to the other
side to move or align it in a more convenient position for storage
or to provide a more convenient use position.
[0148] The illustrated patient outlet 25 is adapted to allow both
pneumatic and electrical connection to one end of a conduit, e.g.,
the conduit 21, that extends between the unit 6 and a patient
interface, e.g., the interface 4. An example of the type of
connector that can be used and the type of dual connection that can
be made is described in U.S. Pat. No. 6,953,354, which is hereby
incorporated by reference in its entirety. It should be noted that
for the purposes of reading this specification, the patient
interface generally can be thought of as including both the
interface 4 and the conduit 21 where it would be appropriate to
read it in this manner.
[0149] The currently preferred embodiment of integrated unit 6
includes an inlet vent or inlet port (not shown) to draw air in
from atmosphere. In alternative embodiments, the inlet port or vent
could be a connector adapted to receive gases from a wall source,
pressure bottle or the like. The integrated unit 6 can also include
a mechanism for providing a pressurized air flow from the inlet
vent to the humidifier chamber, which, in some embodiments, is a
fan unit that acts as a pressurized air flow mechanism. The vent
can be located wherever is convenient on the external surface of
the integrated unit 6. In some embodiments, it is located on the
rear face of the blower unit 7.
[0150] The air is ducted or otherwise directed along an air path
through the casing of the blower unit 7 and delivered to the
humidifier chamber 12, where it is humidified and heated, before
passing out of the humidification unit 31 and onwards to the
patient outlet 25 on the blower unit 7. The heated humidified gas
then passes to the user 3 via the conduit 21.
[0151] The outlet port or patient outlet 25 is adapted to enable
both pneumatic attachment of the patient conduit 21 and electrical
connection via an electrical connector. In FIG. 3, a conduit
connector 34 that would normally be fitted to the end of the
conduit 21 is shown connected to the patient outlet 25. The outlet
port or outlet connection does not have to be via the housing of
the integrated unit 6, as in the illustrated embodiment. Instead,
the connection for the conduit 21 could be located directly on an
outlet from humidifier chamber 12. The illustrated form and
variations generally can be referred to as connection
mechanisms.
[0152] The blower unit 7 also contains electronic circuitry
enclosed within the casing, which at least partly comprises a
controller, such as a microprocessor or the like, and which
provides control signals to control the output or outputs of at
least the blower unit 7, and preferably other items such as the
humidifier chamber 12. The control circuitry also can be adapted to
receive signals from sensors in the system (e.g., pressure, flow,
humidity and temperature signals from these sensors as applicable)
and to alter outputs from the control circuitry accordingly. The
control circuitry also receives signals from user controls as the
user controls are manipulated by a user and alters the output
signals accordingly.
Active Status Indicator
[0153] As outlined above, one of the major design considerations
when designing and manufacturing domestic breathing assistance
systems is a desire to minimize operating noise as much as
practically possible. However, effective noise reduction can lead
to some unforeseen secondary difficulties. If the noise reduction
is too efficient, it can be difficult for a user to establish
whether or not the apparatus is operating(i.e., producing a gases
stream suitable for therapy). Software or control routines can be
included that can. gradually increase, or ramp up, the operating
flow or pressure from an initial start mode (i.e., low pressure and
low flow) to a full operating mode (i.e., higher pressure and
higher flow). Ramp modes or the like allow a user to fall asleep
before they experience full gases pressure and flow, which can be
irritating to a user who is awake and which can reduce the ability
of a user to easily fall asleep. As a user falls asleep, the
pressure and flow increase gradually (i.e., "ramp up") to full
operating conditions. However, when using these type of "gradual
start" or "ramp up" routines, it is possible that a user can fall
asleep thinking that the machine is active but not yet in a full
operating mode (i.e., the machine will ramp up once they are
asleep) when the machine is actually inactive or in a standby mode.
This can be inconvenient because a user will not receive the
desired therapy and may not receive adequate fresh gases.
[0154] Even if "ramp up" routines are not used, it is possible for
a user fall asleep assuming that a machine is running when it is
actually inactive and thus not receive the desired therapy. With a
machine that has been designed to have effective noise reduction,
there is little aural reminder of the operating status. The system
can be on, but not running in an operating mode, and so a user can
inadvertently think that the system is operating. In embodiments of
the present invention, this problem is solved by including a
display that visually indicates the operating or function
condition, or that includes an indicator as part of the main user
display. If the unit is in an operating mode (i.e., a mode in which
it actively is, or shortly will be, providing flow and pressure for
therapy), then the visual indicator is active. If, in contrast, the
unit is off or in a standby mode where pressure and flow at
therapeutic levels will not be provided unless the situation
changes, then the visual indicator is inactive. In some
embodiments, the user display 9 includes or incorporates the visual
indicator that shows whether or not the system is in an operating
mode. In some embodiments, the visual indicator could be separate
from the main display 9; however, the presently illustrated
configuration includes the visual operational indicator as part of
the main LCD display 9.
[0155] According to some embodiments, the assisted breathing unit 6
has a plurality of operating modes. For example, the unit 6 may
provide a CPAP mode with a delayed start, a CPAP mode with an
initial pressure ramp and an automatically titrating mode that
manages the therapeutic pressure in response to sleep disordered
breathing events.
[0156] Preferably, the controller activates the same visual
indicator in respect of all modes in which therapy is being, or
will be, supplied. For example, the controller activates the visual
indicator when any of the CPAP operating modes is active but leaves
the visual indicator inactive when the unit is in a standby
mode.
Removable Peripheral Device Connection Display
[0157] In some embodiments, the breathing assistance apparatus also
is adapted to allow the attachment of a removable peripheral device
or a removable memory device 10 that can have a read-writable
memory and an integral connector 11. In some embodiments, the
removable memory device 10 is a Universal Serial Bus (USB) memory
stick type of electronic storage device. Alternatively, the
removable peripheral device may be any type of removable or
portable (e.g., pocket-sized or the like) electronic storage
device, such as a smart card. The removable memory device 10 may
also include embedded integrated circuits that can process
information and store data.
[0158] The integral connector 11 of the removable peripheral device
10 is adapted for removable connection to the blower unit 7 via a
slot or port 13 on the casing of the blower unit 7. An electrical
communication pathway is formed when the peripheral device 10 is
connected to the port 13 on the blower unit 7 or another portion of
the assisted breathing unit 6. Once the connection is made, data
can be uploaded to or downloaded from the removable memory device
10 to the controller of the assisted breathing unit 6, which in the
preferred embodiment is inside the casing of the blower unit 7.
[0159] As has been outlined above, one problem with removable
devices of this type is that they can easily be connected
improperly, or they can easily become at least partly disconnected
during use. This improper connection, incomplete connection or
disconnection can occur in a manner that is not easily or
immediately apparent to a user at first glance, In other words, the
improper connection, incomplete connection or disconnection is not
immediately or easily visually apparent.
[0160] Certain features, aspects and advantages of the present
invention overcome this problem by having a connection display that
is adapted to indicate to a user that the removable peripheral
device 10 is correctly connected.
[0161] In some embodiments, the user display 9 includes or
incorporates the visual indicator which shows whether or not the
removable peripheral device 10 is correctly connected to the port
13. That is, the connection display is incorporated as part of the
main display 9, with the controller activating part of the display
to show that the removable peripheral device 10 is correctly
connected to the port 13 and to visually indicate to a user that
the connection has been correctly established.
[0162] In alternate embodiments, this visual display could be
separate from the main display 9. For example, the visual display
could be an LED 14 offset from or positioned proximate the port 13.
When the removable peripheral device 10 is correctly connected, the
LED 14 will energize or light up to indicate to a user that the
removable peripheral device 10 is correctly connected to the port
13.
[0163] There are many ways by which this can be achieved. For
example, the integral controller in the blower unit 7 can
interrogate the removable peripheral device 10 and establish if it
is correctly connected or not. Once the controller has established
that the removable peripheral device 10 is correctly connected, the
controller can energize the relevant portion of the display or the
LED 14.
[0164] In a further alternative embodiment, the connection display
does not have to be electronic, but could be a line, a ridge or
other physical visual display indicator on the removable memory
device 10 that aligns with the edges of the slot defining the port
13 to show a user that the removable peripheral device 10 is
correctly connected.
[0165] In a yet still further embodiment, the integral controller
is not required to carry out any actions to establish if the
connection has been made. Rather, correct insertion of the
removable peripheral device 10 into the port 13 could close a
switch or otherwise complete an electrical circuit or the like
which would not be closed or completed unless it was correctly
inserted, and which is isolated from, or otherwise independent of,
the main controller. Completing the electrical circuit activates or
energizes the visual display (e.g. the display or the LED 14).
Conduit Connection Display
[0166] As outlined above, incorrect connection or reconnection of
the conduit or hose 21 to the gases source via connector 25 can
cause breathing gas leaks. Incorrect connection can also mean that
the desired electrical contact between the static gases source
(e.g., the blower unit 7 in the preferred embodiment) and the
electrical elements in the conduit 21 can be intermittent or
non-existent. Certain features, aspects and advantages of the
apparatus of the present invention solves this problem by including
a conduit connection display as part of the apparatus. In the most
preferred embodiment, the LCD user display 9 includes or
incorporates the visual indicator that shows whether or not the
conduit 21 is correctly connected. In other words, the conduit
connection display can be incorporated as part of the main display
9 with the controller activating part of the display to show that
the conduit 21 is correctly connected and to visually indicate to a
user that the connection has been correctly established.
[0167] In an alternative form, the conduit connection display could
be a separate LED 15 located at or close to the patient outlet
25.
[0168] For example, the controller can establish that the
connection between the patient outlet
[0169] 25 and the conduit 21 has been correctly made by sending an
interrogation signal or like and then visually indicate to a user
(e.g., energize the relevant portion of the LCD display 9 and/or
the LED 15) that the connection has been correctly made.
[0170] There are many ways in which the controller may establish
that the connection has been correctly made: by sending an
interrogation signal, by receiving signals indicative of current
flow, air flow or pneumatic pressure and comparing these to stored
values, or by receiving a signal that could not be sent unless a
physical connection had been made correctly within the patient
outlet 25 and the conduit 21 (e.g., correctly connecting the two
items could close a switch or make the final connection in a
dedicated electrical pathway).
[0171] In a yet still further embodiments, the integral controller
is not required to carry out any actions to establish if the
connection has been made. For example, correct connection of the
conduit 21 to the connector 25 could close a switch or otherwise
complete an electrical circuit or the like, which is independent of
the controller. Completing the electrical circuit either directly
or indirectly activates or energizes the relevant portion of the
display 9 or the LED 15.
Control Menu Functionality
[0172] In the preferred embodiment, the control menu is displayed
on the display 9. In the preferred embodiment, the display 9 is an
LCD display. The illustrated display 9 provides a circular ring of
options adjacent the outer edge of the display 9. As the knob 8 is
rotated, each of the options will activate in turn. When the knob
or other selection button is depressed by the user, the activated
option will be chosen. Once an option or parameter is chosen, for
example "output power", the level of this option or parameter can
be adjusted by rotating the knob 8 clockwise and anticlockwise. A
user then can exit this submenu and return to the main menu by, for
example, tapping the knob inwards or pulling it outwards. The
control circuitry can be programmed as required. Other options can
be pre-programmed as desired. For example, pushing and holding in
the knob 8 (or pulling it outwards and holding it out) could turn
the unit off.
[0173] It is preferred that the mechanism of the knob 8 has a
series of physically discrete positions and that the knob requires
a small force to move between these positions. Preferably, the
discrete positions (the "cogging" positions) that the knob 8
reaches as it is rotated correspond to different menu option
positions.
[0174] The user interface functionality can be implemented by the
controller. For example, the controller can include a stored
control program and parameter data. The parameter data can include
data indicating the accessibility status of each of the options. As
will be discussed below, the controller activates the display icon
of each of the accessible options. According to the control
program, the controller may cause a predetermined icon from the
displayed icons to be initially highlighted. For example the
controller may activate an additional display element proximate to
the icon. As the controller receives indications of movement of the
knob 8 in a direction, the controller selects (as the direction
dictates) an adjacent accessible option, removes highlighting from
the initial icon and highlights the icon of the next option.
[0175] When the controller receives input of a selection button
press, the control program responds by calling a routine associated
with the option presently active and highlighted. This routine may
invoke further layers of menu functionality, or may provide for
setting a usage parameter. Preferably, the routine will display
information and options for amending or changing the
information.
[0176] As has been outlined above, breathing assistance apparatuses
are getting more complex and sophisticated and the number of
control options has increased. An end user does not require a high
level of control sophistication and can easily become confused or
overloaded if presented with too many options for adjusting or
controlling the output. Too many options can also be
counter-productive if a user does not entirely understand the
implications of changing the control parameters. However, a health
professional may require a greater degree of control input when
making adjustments to the operating conditions than is desired by
an end user.
[0177] In order to overcome this problem, certain features, aspects
and advantages of the preferred embodiment of the device of the
present invention includes a, way of removing access to a variable
amount of the control functionality. A clinician or other health
professional will have access to the full spectrum of functionality
but can set the user interface so that an end-user (i.e., a person
who receives therapy from the system) will initially be able to
access a certain amount of control functionality, and will be
locked out or otherwise unable to access some of the more
sophisticated control elements or control subroutines. The user
interface is adapted to display a control menu that has a number of
control and display options. The controller has control options
that are able to be manipulated to hide or block at least one, and
preferably a plurality, of the control and display options. Once
hidden, the control options are able to be manipulated to unhide or
unblock the control and display options. In contrast, a health
professional will be able to access those elements that are denied
to the end user, by unlocking another level of the interface in
order to access a greater range of functionality.
[0178] For example, a routine of the control program may include
program code for presenting on the screen options for amendment of
the accessibility parameter data. In response to user input using
the knob and button, the controller may then adjust the stored
parameter data.
[0179] Alternatively, the control program may update stored
parameter data using data received over an external communication
interface, or uploaded from a portable memory device.
[0180] If appropriate, once a user becomes more familiar with their
own apparatus, they can be given access to some or all of this
extra functionality. The control system is configured so that it is
possible to gradually unlock more and more of the functionality, or
to lock out or unlock various different individual functions or
combinations of individual functions. This can be achieved by using
a keying mechanism (electronic or otherwise), a password-protection
routine, or any of a number of similar mechanisms or methods that
are known in the art. For example, the routine of the control
program intended for amending the accessibility settings may
include steps for displaying a prompt for password input, receiving
input data in the form of a sequence of knob rotations, button
pressures, or both, and check the input sequence against stored
comparison data. Alternatively, the routine may prompt the user by
sound or display, for example, to identify themselves using a
biometric sensor on the unit or by inserting a personalized data
storage device. Embodiments of the control functionality will now
be described with reference to FIG. 5.
[0181] In the illustrated embodiment, the user display 9 is capable
of displaying a number of symbols and menu options relating to the
control and output of the blower unit 7, for example. The
controller can be initially set so that the totality of these menu
functionality symbols and icons can be viewed, as shown in FIG. 5e
(e.g., a "clinician mode"). More limited menu options are shown in
FIGS. 5a-d, where various combinations of the icons and symbols are
hidden or "blanked out", and are unavailable. One or more of these
menus can be selected and made available to a user. For example, in
some embodiments, the menu options shown in FIGS. 5c and 5e can be
blocked while those shown in FIGS. 5a, 5b, and 5d remain available
to be selected as desired. Alternatively, access to the most basic
of menu functions and display, as shown in FIG. 5a, initially can
be provided and, over time and with experience, greater
functionality can be unlocked. For example, a clinician can, after
a certain period of time, unlock the second menu as shown in FIG.
5b to allow a user access to the greater functionality. Then, after
a certain time, a yet more complex menu/display as shown in FIG. 5d
can be unlocked. The clinician can also "re-lock" the menu
functions as desired. In some embodiments, the controls are
configured so that all possible combinations of menu functionality
are available.
[0182] The controller may include functionality to effectively
disable the user input controls according to certain conditions. In
particular, the controller may disable the effect of the user input
controls after a period of non-use of the controls. The control
program may implement this functionality in any suitable way.
[0183] For example, the control program may set (or reset) a
response timer each time a user control is activated, and steadily
reduce the value of the timer. When user input is sensed, the
program may check the response timer and either respond to the
sensed input if the timer is above zero or, if the timer has
expired, respond to the sensed input by implementing an activation
test. The activation test may include displaying a prompt
requesting specific manipulation of the controls to activate the
user interface. The program monitors for sensed inputs
corresponding with the specified manipulations. For example, the
specified manipulation may be depressing the button for a
predetermined period, depressing the button a predetermined number
of times, or performing a sequence of rotations of the knob. If the
program receives data indicating manipulations that match the
requested sequence, the program resets the timer so that subsequent
user input is not blocked. Otherwise, the controller ignores the
user input. The program may start or reset an additional short
timer at each sensed user input during the test, and exit the test
mode if the short timer expires.
[0184] By way of example, user input may be disabled after an
inactive period preset to a value between 5 and 10 minutes and user
input may be enabled by depressing the button for 3 seconds.
[0185] The intention of disabling user input is to reduce the
likelihood that the device will be easily disrupted during
operating modes because of, for example, the dark bedroom
environment in which the device will usually be used.
[0186] As an additional step in deciding whether to act on user
input, the control program may respond differently according to
other operations of the device. For example, the control program
may only disable input during an operating mode, and not when in
standby mode. In some configurations, the control program may have
certain modes where it will respond to some or all user input. For
example, the control program may respond to input when the
controller also is sounding an alarm. Such a configuration ensures
that a user does not need to complete the activation test merely to
deactivate the alarm.
Power Conservation Mode
[0187] The improved form of breathing assistance apparatus is
adapted to be capable of connection to an external power supply. In
some embodiments, the blower unit 7 has a socket to allow the unit
to be connected to a source of mains power (e.g., either by
plugging a power lead into the unit or via its own integral
built-in lead). In normal operating mode, breathing assistance
systems can use a large amount of power over an extended period
(e.g., when running at full power for a full eight-hour sleep
period). This is not normally an issue if the system is connected
to a source of mains power. However, there are occasions when a
user may not have access to a mains power supply. For example, if
the user is traveling then they may not be able to connect their
system to a mains power source. The user could be on a long-haul
flight. Alternatively, the user could, for example, be a trucker,
fisherman or member of a similar group who regularly sleep in their
vehicles.
[0188] Certain features, aspects and advantages of the preferred
embodiment of the present invention therefore have the control
program capable of causing the controller to provide a power
conservation or power saving mode, which is user-selectable or
which the apparatus automatically switches to if the controller
senses that it is running on a supply other than a mains power
supply. Thus, the control program can automatically switch from a
standard or full-power mode to a power saving mode. Alternatively,
if the power-saving mode is intended to be user-selectable, the
control program may allow the user to manually select the power
saving mode via the user interface. In some embodiments of the
power saving mode, the controller limits work done at a maximum
rate of between 50 and 100 Watts, or at about 75 Watts. However, in
alternative embodiments, the control program may allow a user to
set the maximum rate, or the rate could be pre-programmed at a
different maximum. The control program may allow a user to switch
back to full power mode when the unit is connected to a mains power
supply, or the controller may be programmed to automatically switch
back to a full power mode once reconnected to a source of mains
power. Alternatively, the control program may allow a user to
manually override the power saving mode and switch to the
full-power mode when the unit is not connected to a mains source,
if desired.
[0189] There are several ways in which the control program may
detect whether it is connected to a non-standard or non-mains
source of power. Several ways in which the system can detect this
are outlined below.
[0190] Firstly, as has been outlined above, a user may plug their
system into the electrical circuit of an aircraft. Typically, a
normal mains circuit will operate at a certain frequency--for
example, in the USA, the mains circuit is AC and operates at 60 Hz.
In Europe, and many other countries, the AC mains circuit operates
at 50 Hz. An aircraft's electrical circuit will for example, run an
electrical system at 400 Hz rather than 60 Hz. The advantage of
this is that the power supplies are smaller and lighter, a prime
consideration in aircraft design. An electrical system of this
type, capable of powering devices usually powered by mains power
can be generally referred to as providing a synthesized mains AC
power supply. When a user plugs their breathing assistance system
into the aircraft's electrical system, the electrical circuitry in
the system will receive power at a frequency of 400 Hz. In one
embodiment, the electronic circuitry of the system is adapted to
detect the frequency of the power supply. If the power supply is
delivered at a "mains" frequency (e.g. 50 Hz for Europe, 60 Hz for
the US, etc), then the electronic circuitry operates the system in
a standard mode, and the system is powered as normal. If the
electronic circuitry detects that the frequency of the power supply
is outside this pre-set range, then the controller will switch the
system to the power-saving mode.
[0191] In a vehicle such as a truck, the electric circuit is
usually battery-powered and is usually a 12V or 24V DC supply. A
mains-type socket may be provided in the circuit to allow a user to
plug mains-enabled devices into the circuit to draw power from the
vehicles power supply. Usually, an inverter will be fitted in the
circuit to convert the DC current of the vehicle circuit to AC so
that AC devices can be powered. Power provided in this manner can
generally be referred to as a synthesized mains AC power
supply.
[0192] In some embodiments of the breathing assistance system, the
system can be fitted with a detector that receives a signal
indicating that it should switch from the normal mode to the
power-saving mode. For example, the system can be fitted with an
infra-red detector or a Bluetooth detector, for example, connected
to the electronic circuitry. On receiving a signal indicating that
synthesized mains AC power is being provided, rather than "true"
mains power, the system will switch to the power-saving mode.
Alternatively, a secondary signal can be superimposed over the
power supply signal, the secondary signal detected by the
electronic circuitry of the breathing assistance system, and the
circuitry switching the system to the power-saving mode on
detection of the superimposed signal.
[0193] Alternatively, the system can be fitted with user controls
that are adapted to allow a user to manually switch between a
standard operating mode and a power saving mode.
[0194] The controller in alternative forms could also be powered by
an internal power source or batteries. The system could switch
automatically to a power-saving mode when disconnected from a main
power supply, or this could be carried out manually by a user using
the user controls.
[0195] As shown in FIG. 3, and described above, the blower unit 7
has the patient outlet 25 passing out of the rear wall of the
integrated unit 6. As described above, the patient outlet 25 is
adapted to allow both pneumatic and electrical connection to one
end of a conduit (e.g., the conduit 21) running between the unit 6
and the patient interface (e.g., the interface 4). In some
embodiments, an integrated unit (or modular unit) that includes an
improved form of elbow has two advantages over the prior art.
Firstly, the elbow is removable from the rest of the blower unit 7
for cleaning, maintenance, or the like. Secondly, the elbow is
structured in such a manner that gases flowing through it are
insulated. Thus, the heated humidified gases passing out of the
blower unit tend to lose less heat to the atmosphere or ambient
surroundings than would otherwise be the case. Embodiments of an
elbow connector that embodies these two advantages will now be
described with reference to FIGS. 6, 7, 8 and 9. It should be noted
that these two advantages do not have to be simultaneously
realized, and that each could be realized separately from the
other.
[0196] Removable elbow connector A close-up of the blower unit 7 is
shown in FIG. 6, looking from above and to the rear, from one side.
The enclosure 42 for the humidifier unit 31 is shown with the
humidifier unit 31 removed from the blower unit 7.
[0197] In use, the outlet of the humidifier chamber 31 connects
with the inlet aperture 30 of a removable seal 32. The removable
seal 32 forms an outlet gases passage such that heated humidified
gases from the humidifier chamber 31 can pass into the patient
outlet 25 and on to the patient 1. In some embodiments, at least
the inlet aperture 30 of the removable seal 32 is formed from a
soft sealing material, such as silicone rubber, for example but
without limitation. The structure and composition of the removable
seal will be described in greater detail below.
[0198] FIG. 7 shows further detail of the connection between the
patient outlet or elbow 25 and the rest of the blower unit 7. For
clarity, the outermost casing of the blower unit is not shown. The
path between the inlet aperture 30 and the elbow connector 25 can
be seen.
[0199] FIG. 8 shows an exploded view of those parts of the blower
unit shown in FIG. 7. The enclosure 42 for the humidifier chamber
31 is shown. Also shown are the patient connector 25, the removable
seal 32, and a sealing/connection ring 33 that rigidly connects to
the inner end of the patient connector or elbow 25. Preferably,
when connected together, the sealing ring 33 and the elbow 25
cannot move relative to one another.
[0200] The structure of the illustrated elbow 25 now will be
described with particular reference to FIG. 10. The illustrated
elbow connector 25 is formed so that it has substantially a
right-angle or 90-degree bend at the centre, which divides the
elbow 25 into two halves or portions of substantially equal length.
An inner portion closest to the blower unit is adapted to connect
to the blower unit 7 in use. An outer portion in use connects to
the patient conduit 21. The inner end 36 of the inner portion of
the elbow 25 is formed as a gases inlet so that in use it can
receive gases from the humidifier 31. The outer portion connects to
the inner end of the conduit 21 in use.
[0201] The illustrated sealing ring 33 is formed as a rigid ring
that fits over and around the inner end 36 of the elbow 25. The
inner end 36 has a pair of indents or slots 47 formed on the outer
surface thereof, with a pair of complimentary ridges 48 formed on
the inside surface of the sealing ring 33. These allow the sealing
ring 33 and the elbow connector 25 to clip or slot together via
friction fit, for example. In other words, the ridges 48 may fit
into the slots 47 to hold the two parts together.
[0202] The illustrated sealing ring 33 also includes an electrical
connector 19. The electrical connector 19 preferably fits into an
indent or recess 35 in the elbow 25. The recess 35 can be formed on
or at the inside corner of the elbow 25. The electrical connector
preferably is aligned so that when the sealing ring 33 and the
elbow 25 are connected, the electrical connector 19 is generally
parallel with the outer portion or half of the elbow 25. This
allows electrical and pneumatic connection between the elbow 25 and
a connector on the end of conduit 21 to be achieved easily in one
action.
[0203] In use, the illustrated sealing ring 33 is fitted into the
outer casing of the blower unit 7 and is generally non-removably
held in position therein. For example, a circlip or similar
engaging mechanism may be interposed between the casing and a
flange of the sealing ring. Such a configuration can best be seen
by comparison of FIGS. 6 and 7, with FIG. 6 showing the outer
casing and FIG. 7 showing a similar view with the outer casing not
shown. Because the elbow 25 is held in place by a friction fit with
the sealing ring 33, for example, the elbow 25 can be removed by
pulling it outwards away from the blower unit 7. This allows the
elbow 25 to be easily removed for cleaning or replacement as
desired.
Insulated Elbow Connector
[0204] One well-known problem with the provision of heated,
humidified gases to a user from a CPAP-style system is that the
blower and humidifier components of the system tend to be located
at a distance from the point of delivery. There is therefore some
difficulty in maintaining the temperature of the gases between the
blower/humidifier part of the system and the point of delivery. In
the art, this is mainly addressed by heating the conduit 21 to
maintain the temperature. However, it remains desirable to minimize
as far as possible all potential ways in which heat can escape from
the gases.
[0205] In accordance with certain features, aspects and advantages
of the preferred embodiment of the present invention, gases exiting
the humidifier unit 31 enter the removable seal 32 and then pass
into the elbow 25. The outer end of the removable seal 32 is
located inside the inner end of the elbow 25 such that there is
some overlap between the two.
[0206] FIG. 9 shows a cross-section of the seal 32, the blower unit
7, the sealing ring 33 and the elbow 25. As can be seen, the outer
end of the seal 32 passes into the inner end of the elbow 25, and
there is overlap between the two. Gases traveling through the
innermost portion of the elbow 25 are insulated from atmosphere
because they are surrounded by the removable seal 32, the inner
portion of the elbow 25, and the sealing ring 33. The outer arm or
outer portion of the elbow 25 is in use surrounded by the connector
portion 34 of the conduit 21, as can best be seen in FIG. 3. This
effectively insulates the gases in the outer arm of the elbow 25.
With reference to FIGS. 9 and 10, the remainder of the elbow 25,
the outer portion of the inner arm, is insulated by surrounding an
inward gases passage 37 with an insulating wall 38, spaced from the
inward gases passage 37 so that an airgap 50 is formed between the
passage 37 and the wall 38. In use, this airgap 50 is closed to the
atmosphere on its open side (i.e., the inner or blower side) by the
sealing ring 33.
[0207] In this embodiment, the air gap 50 completely surrounds the
inward gases passage 37, except for the recess 35. The recess 35
has the effect of causing the insulating wall 38 to curve inwards
to contact the passage 37, as best seen with reference to FIG.
10a.
[0208] The air gap 50 between the inward gases passage 37 and the
insulating wall 38 serves to insulate the gases flowing through the
elbow 25 and assists in retaining the heat of these gases.
Removable Seal
[0209] The removable seal 32 will now be described with particular
reference to FIGS. 9 and 11. As described above, the outlet of the
humidifier chamber 31 connects with the inlet aperture 30 of the
removable seal 32 so that heated humidified gases from the
humidifier chamber can pass through the removable seal 32, into the
patient outlet 25 and then on to the patient 1. The removable seal
32 forms an outlet gases passage for the blower unit. In some
embodiments, the entirety of the removable seal 32 is formed from a
soft, flexible material, such as silicone rubber, for example but
without limitation. With reference to FIG. 11a, the overall form of
the illustrated seal 32 is that of a funnel. The inner portion of
the seal 32 forms a wider mouth 60 of the funnel.
[0210] The opening of the mouth 60 (i.e., on the inner side) is
substantially rectangular such that the mouth portion of the funnel
has the shape of a rectangular funnel. The opening of the
illustrated mouth 60 is surrounded by a flange 61 that in use seals
against the side surface of the rear wall of the enclosure 42.
[0211] The flange 61 can, if desired, include ridges or the like
(not shown) that press-fit into complimentary sockets or slots in
the blower unit to hold the removable seal 32 in position. In some
embodiments, the flange 61 and at least part of the mouth 60 are
curved so as to fit flush against the curved rear wall of the
enclosure 42.
[0212] The outer portion of the illustrated removable seal 32 forms
a stem 62 of the funnel.
[0213] The outermost end of the stem 62 has a rim 63 that is wider
than the remainder of the stem 62. The rim 63 is shaped so that the
stem 62 and the rim 63 has a barbed appearance in cross-section
with the rim 63 being wider at the inner side than at the outer
side. In use, to assemble the illustrated blower unit, the
removable seal 32 is pressed into and through an aperture in the
rear wall of the blower unit to form an outlet passage from the
humidifier chamber outlet, through the wall of the blower, and into
the elbow 25. The illustrated rim 63 has an interference fit with
the inner surface of the inward gases passage 37 of the elbow such
that a seal is formed between the two.
[0214] The removable seal 32 can be removed from the blower easily,
such as by pulling it out of the wall of the blower unit. This is
useful for cleaning, maintenance or replacement. The interference
fit between the stem 63 and the inner arm of the elbow 25 provides,
a gas-tight seal between the two components. The elbow 25 may still
be rotated relative to the removable seal (i.e., the rotation
taking place around an axis that substantially forms the centre
line of the stem 62).
Humidifier Chamber
[0215] The humidifier unit 31 will now be described in more detail
with reference to FIGS. 13-17.
[0216] In some embodiments, the humidifier unit 31 is comprised of
three main parts: a humidifier chamber 112, a lid 132 and a locking
handle 122, which is counted as part of the humidifier unit for the
purpose of describing the operation of the integrated unit 6.
[0217] In some embodiments, the humidifier chamber 112 is an
open-topped container with a heat conducting base. The illustrated
chamber 112 is sized to fit snugly within the enclosure 42 on the
integrated unit 6. In other words, the chamber 112 is enclosed
within the blower unit except for the open top of the chamber 112.
A fully open topped chamber 112 can be provided. However, an
alternative form of the chamber 112 could have a closed top
surface, and would include an opening on the chamber positioned
(e.g., not necessarily on the top surface) and sized appropriately
so that a user can easily fill the chamber 112. This opening could
be one of the apertures that are normally used for gases delivery
in use. The chamber 112 with an open top, and the alternative form
that includes a fill opening on the top are referred to as "open
top", or "top openings" within this specification. The open top may
also be referred to as a "top fill aperture". It should also be
noted that when the humidifier chamber 112 is referred to as
"enclosed", or "substantially enclosed" in relation to the
integrated breathing assistance apparatus, this has the meanings
consistent with the construction defined above.
[0218] In some embodiments, the chamber 112 is a generally circular
cylinder, but the lower part of the rear (relative to the
integrated unit 6) is flattened and indented to correspond to ledge
133 on the lower rear side of the enclosure 42. This assists the
chamber 112 to be oriented correctly in use. It should be
understood that other methods of achieving the same result could
also be used. For example, the chamber 112 and integrated unit 6
could include complimentary grooves and slots or the chamber 112
could be non-cylindrical so that it only fits the housing in one
orientation.
[0219] The chamber 112 can also include features such as a fill or
level line.
[0220] A humidifier inlet port 115 and a humidifier outlet port 116
can be located in the wall of the humidifier chamber 112. In the
illustrated configuration, the inlet port 115 and the outlet port
116 are located towards the top of the chamber wall. These are
positioned so as to align with a blower inlet port and a blower
outlet port when the humidifier chamber 112 is in position. In use,
air from the blower unit passes into the humidifier chamber 112
through the humidifier gases inlet port 115, passes through the
chamber (becoming heated and humidified as it does so), and exits
the humidifier chamber 112 through the humidifier gases outlet port
116 and passes into the passage formed by the removable seal 32.
The internal structure of the humidifier chamber shall be described
in detail below.
[0221] In use, the chamber 112 is positioned (i.e., in the correct
orientation) within the enclosure 42. The lid 132 then is placed on
top of the chamber 112. The lid 132 is sized so that it will pass
through the top opening of the integrated unit 6. A lower surface
of the lid 132, close to the edge, seals onto the upper edge of the
chamber 112.
[0222] The lid 132 is placed in position on the chamber 112 once
the chamber 112 has been filled. The locking handle 122 then is
positioned above the lid 132. Lugs 127 on the circumference of the
locking handle 122 engage with complimentary grooves 126 on the
blower unit 7 to lock the lid 132 in position.
[0223] The generally cylindrical chamber 112 and round lid 132 have
been described, with locking/unlocking of the lid 132 achieved by
rotating the separate locking handle 122. However, this is not the
only way in which this effect can be achieved. For example, spring
, loaded clips could be used, with the clips released by a button
placed in a convenient location. A hinged lid could also be used,
with a clip and complimentary catch located on the lid and the
blower unit, to hold the lid closed in use. Alternatively, the
chamber lid 132 and the locking handle 122 could be integrated as a
single unit.
[0224] In some embodiments, the rim or perimeter of the chamber 112
also includes a chamber seal 110, formed from soft silicone or
similar. When the chamber 112 is placed in position in the
enclosure 42, the chamber seal 110 is pressed against the wall or
walls of the enclosure 42 to ensure that the chamber 112 is sealed,
so that air entering the chamber from the blower cannot escape to
atmosphere. If desired, a substantially unbroken ring of sealing
material such as soft silicone can be provided to the wall of the
enclosure 42 at or close to the upper rim of the chamber 12, to
form a compartment seal (not shown) instead of or as well as the
chamber seal 110.
[0225] As can be seen in FIG. 13, the humidifier chamber 112 can be
substantially circular in plan view. An inlet passage 134 and an
exit passage 136 can be aligned or defined radially.
[0226] Gases enter the humidifier chamber 112 through the
humidifier inlet port 115, and pass along the generally horizontal
entry passage or inlet passage 134. The passage 134 is aligned
radially towards the centre of the humidifier chamber 112.
[0227] As can best be seen with reference to FIGS. 14 and 15, the
inlet passage 134 is open-topped at the end closest to the centre
of the chamber. When assembled, the open top is closed by a
removable cap 202. The cap 202 is formed as a removable item
because this aids in manufacture and moulding of the chamber 112.
Edges of the cap 202 also act as a handle, allowing a user to grip
the cap and pull the chamber 112 out of the enclosure 42.
[0228] As best seen in FIG. 15, one portion 140 of the side of the
inlet passage 134 is reduced in height. When the cap 202 is in
position, there is an aperture in one side of the passage (i.e.,
between the portion 140 and the cap 202) to allow gases to exit the
inlet passage 134 and to enter the main body of the chamber
112.
[0229] This aperture is referred to as the primary gases inlet
aperture, as it allows gases to exit the inlet passage 134 and
enter the main body of the chamber 112.
[0230] Also, an inlet passage recess 300 is formed in the lower
surface or part of the passage 134 towards that end that is closest
to the centre of the chamber 112. At least one or a number of
secondary inlet apertures 301 are formed within the inlet passage
recess 300, possibly on the lower part or surface, facing
substantially vertically downwards into the humidifier chamber
112.
[0231] A proportion of the gases exit the inlet passage 134 through
the entry apertures 301 and enter the main body of the humidifier
chamber 112. The greater portion of the gases will exit into the
main body of the chamber 112 through the primary inlet aperture,
which is considerably larger than the secondary inlet apertures
301. However, the presence of the inlet recess 300 and secondary
inlet apertures 301 is advantageous, as it forces at least a
proportion of the gases entering the main body of the chamber 112
downwards towards the surface of the water, and increases the
length of time that a given volume of gases will spend in the
chamber such that the gases are more likely to be heated and
humidified to the required level before exiting the chamber. In
use, the gases in the main body of the chamber 112 are heated and
humidified, and exit the main body of the chamber 112, entering the
exit passage 136. The exit passage is, in the exemplary embodiment,
aligned radially, with one end. at the centre of the chamber 112,
connected to the end of the entry passage 134, the ends of the two
passages are separated by an internal wall, so that in some
embodiments, the passages are structurally connected but
fluidically disconnected. The exit passage 136 has reduced height
(or non-existent) side walls and an open top at that end that is
closest to the centre of the chamber 112, as can best be seen with
reference to FIG. 15. The cut out sides form primary gases exit
apertures.
[0232] The exit passage 136 also includes an exit recess 303 formed
in or on the lower surface of an exit passage 136. The exit recess
has a secondary exit aperture or exit apertures 201. The apertures
can be formed on the lower part or surface. The exit recess 303 and
the secondary exit apertures 201 are, in some embodiments, formed
at that end of the exit passage closest to the centre of the
chamber 112. The secondary exit apertures 201 face substantially
vertically downwards into the humidifier chamber 112. When fully
assembled, the open top of the exit passage 136 is closed by the
cap 202. Heated humidified gases from the chamber 112 enter the
exit passage through the primary exit apertures in the sides of the
passage, and through the exit apertures 201.
[0233] The majority of the gases enter the exit passage through the
primary exit apertures in the side wall. The gases pass along the
exit passage 136 to the chamber exit port 116 and then into the
passage formed by the removable seal 32, and on to the user 3 as
described above.
[0234] In some embodiments, the angle between the inlet passage 134
and the exit passage 136 is about 125 degrees between their
centrelines, when viewed from above or in plan. The passages can be
at an angle between 110 degrees and 160 degrees. This has the
advantage that the fitting position of the chamber is easy to
identify, and the chamber will only fit in the enclosure 42 in one
orientation. Also, as the chamber inlet and outlet are in
non-symmetrical positions, the chamber can't rotate once
fitted.
[0235] As described above, both the inlet passage 134 and the exit
passage 136 have recesses, an entry recess 300 and an exit recess
303 respectively, with secondary apertures formed in these recesses
to allow a portion of the gases entering and exiting the chamber to
pass through. Although the majority of the gases enter and exit the
main body of the chamber 112 through the primary apertures formed
in the sides of the passage, it has been found that forming these
secondary apertures into the recesses is beneficial, as pressure
drop across the chamber is minimized, and it is easier to produce
and maintain the required amount of humidity. Also, water splash
from the main part of the chamber into the passages is minimized or
eliminated for a tilt angle of 20 degrees or under. This
combination of features advantageously assists during
standardization testing. For example, the combination of features
can assist in meeting the requirements of ISO 8185 clause 44.2,
which states that "when the humidifier is tilted through 20 degrees
in any direction from its normal operating position, there shall be
no spillage of water from the liquid chamber or liquid reservoir
into the breathing system when operated at the maximum flow . . .
".
[0236] As described above, the secondary entry apertures 301 and
the secondary exit apertures 201 are formed in their respective
recesses (300, 201) in their respective passages at a position
towards the centre of the passages. Forming the recesses and
apertures in the passages towards the centre of the chamber makes
it more difficult for water in the chamber to enter the passages if
a filled chamber is tilted in use--the likelihood of splashing
occurring and water entering the exit passage 136 in particular is
reduced. However, forming the entry apertures and the exit
apertures in this manner means that they will be substantially
adjacent to one another, and there is a risk that gases entering
the chamber will not spend sufficient time in the chamber for them
to become heated and humidified to the required levels (dwell
time)--they may tend to cross over or short circuit between the
entry and exit apertures before being suitably heated and
humidified.
[0237] In order to ensure that the gases do not short circuit
through the main body of the chamber and that they "dwell" for a
suitable period within the chamber, the chamber includes a baffle
135 which extends downwards substantially vertically from the ends
of the entry and exit passages, between the entry apertures and the
exit apertures. In some embodiments, the baffle is also slightly
curved horizontally, with the vertical edges curving towards the
humidifier inlet port 115. It can be seen that the baffle 135
reduces the likelihood of air from the inlet passage 134 moving on
a direct path to the exit passage 136.
[0238] As described above, the inlet passage 134 has a primary
aperture on one side only. In some embodiments, this aperture is
formed on that side of the passage that is furthest from the exit
passage (i.e., the two passages being formed at an angle to one
another as described above), and that therefore the gases have a
further distance to travel before exiting the main body of the
chamber 112, further reducing the likelihood of the gases
"short-circuiting" through the chamber (the distance from the point
at which the gases enter the chamber, to the nearest point at which
they can exit, is maximized).
[0239] As can be seen in FIGS. 14 and 15, the chamber can also
include buttress ribs 401, 402 extending radially outwards from
substantially the centre or meeting point/join of the two passages,
towards the periphery or perimeter of the chamber 112. The buttress
ribs 401 , 402 are located at the top of the main body of the
chamber 112. The buttress ribs 401, 402 serve a dual purpose.
Firstly, they strengthen the chamber against crushing forces
applied from the sides (horizontally). Secondly, they deflect gases
which are circulating at the top of the chamber downwards towards
the surface of the water in the chamber. This helps to ensure that
the gases in the chamber are suitably humidified before they exit
the chamber.
[0240] In some embodiments, and in the embodiment shown in the
figures, the humidifier gases inlet port 115 and the humidifier
gases outlet port 116 are located on the perimeter of the chamber
112. In some embodiments, the chamber is circular in plan, so the
perimeter is on the circumference. In an alternative form, the
chamber can be configured so that one or both of the humidifier
gases inlet port and the humidifier gases outlet port are located
at a point or points closer to the centre of the chamber 112. For
example, one or both of the passages 134, 136 could be shortened so
that they only extend part of the way from the centre of the
chamber to the perimeter. The humidifier gases inlet port and the
humidifier gases outlet port in this configuration would be
configured to connect to appropriate inlets and outlets on the
blower or other external piece of equipment. The openings of the
humidifier gases inlet port and the humidifier gases outlet port
could open upwards, or horizontally, for example. The passage
assembly or assemblies in this alternative configuration could be
held in position by the buttress ribs 401, 402.
[0241] Although the present invention has been described in terms
of a certain embodiment, other embodiments apparent to those of
ordinary skill in the art also are within the scope of this
invention. Thus, various changes and modifications may be made
without departing from the spirit and scope of the invention. For
instance, various components may be repositioned as desired.
Moreover, not all of the features, aspects and advantages are
necessarily required to practice the present invention.
Accordingly, the scope of the present invention is intended to be
defined only by the claims that follow.
* * * * *