U.S. patent application number 11/570726 was filed with the patent office on 2007-10-04 for inhaling apparatus.
Invention is credited to Mitsuru Imai, Toshiyuki Nobutani.
Application Number | 20070227534 11/570726 |
Document ID | / |
Family ID | 35787230 |
Filed Date | 2007-10-04 |
United States Patent
Application |
20070227534 |
Kind Code |
A1 |
Nobutani; Toshiyuki ; et
al. |
October 4, 2007 |
Inhaling Apparatus
Abstract
An inhaling apparatus is to be used by a user to inhale a liquid
medical agent from an inhalation port thereof. It has a liquid
medical agent ejecting section having an ejection port for ejecting
a liquid medical agent as droplets and a pressure detecting section
for detecting the negative pressure produced by the atmospheric
pressure as pressure difference at the time of inhalation of the
user for the purpose of controlling the ejection of droplets from
the ejection port. The ejection port of the liquid medical agent
ejecting section is arranged at a position adapted to produce a
pressure difference smaller than the pressure difference with the
atmospheric pressure as detected by the pressure detecting section
at the time of the inhaling action of the user.
Inventors: |
Nobutani; Toshiyuki;
(Kanagawa-ken, JP) ; Imai; Mitsuru; (Saitama-ken,
JP) |
Correspondence
Address: |
FITZPATRICK CELLA HARPER & SCINTO
30 ROCKEFELLER PLAZA
NEW YORK
NY
10112
US
|
Family ID: |
35787230 |
Appl. No.: |
11/570726 |
Filed: |
July 29, 2005 |
PCT Filed: |
July 29, 2005 |
PCT NO: |
PCT/JP05/14370 |
371 Date: |
December 15, 2006 |
Current U.S.
Class: |
128/200.14 |
Current CPC
Class: |
A61M 15/025 20140204;
A61M 2205/582 20130101; A61M 2016/0024 20130101; A61M 15/0066
20140204 |
Class at
Publication: |
128/200.14 |
International
Class: |
A61M 11/00 20060101
A61M011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 2, 2004 |
JP |
2004-225510 |
Claims
1-11. (canceled)
12. An inhaling apparatus to be used by a user to inhale a liquid
medical agent from an inhalation port thereof, the apparatus
comprising: a flow path for forming an airflow by means of an
inhaling action of a user, said flow path having said inhalation
port at a first end thereof and an air intake port at a second end
thereof; a pressure detecting section for detecting a negative
pressure produced in said flow path by the inhaling action of the
user, said pressure detecting section communicating with said flow
path via a communication hole; and a liquid medical agent ejecting
section arranged in said flow path, said ejecting section having an
ejection port and an electrothermal or piezoelectric element for
ejecting the liquid medical agent in response to the negative
pressure detected by said pressure detecting section, characterized
in that a pressure alleviating means is provided in said flow path
at a position closer to the inhalation port than said ejecting
section, for alleviating the negative pressure produced at said
ejecting section, and the communication hole is arranged in said
flow path at the pressure alleviating means or at a position closer
to the inhalation port than said pressure alleviating means.
13. The apparatus according to claim 12, wherein said pressure
alleviating means is a narrowed section having a smaller cross
sectional area in said flow path forming an airflow.
14. The apparatus according to claim 12, wherein said pressure
alleviating means is a valve which opens as the apparatus is
operated for inhalation.
15. An inhaling apparatus to be used by a user to inhale a liquid
medical agent from an inhalation port thereof, the apparatus
comprising: a flow path for forming an airflow by means of an
inhaling action of a user, said flow path having said inhalation
port at a first end thereof and an air intake port at a second end
thereof; and a liquid medical agent ejecting section arranged in
said flow path, said ejecting section having an ejection port and
an electrothermal or piezoelectric element for ejecting the liquid
medical agent, characterized in that a pressure alleviating means
is provided in said flow path at a position closer to said
inhalation port than said ejecting section, for alleviating the
negative pressure produced at said ejecting section.
16. The inhaling apparatus according to claim 15, further
comprising a pressure detecting section for detecting a negative
pressure produced in said flow path by the inhaling action of the
user, said pressure detecting section being arranged outside a flow
path exit in said inhalation port.
Description
TECHNICAL FIELD
[0001] This invention relates to an inhaling apparatus. More
particularly, it relates to an inhaling apparatus for ejecting
droplets of a medical agent, an aromatic, nicotine or some other
savory substance and causes the user to inhale them.
BACKGROUND ART
[0002] Our society is aging because of the prolonged mean life that
is realized by the advancement of medicine and science in recent
years. On the other hand, new diseases and infectious diseases have
been found due to the changes in the living environment and the
eating habits, the environmental pollution and new strains of
viruses and microbes to make people anxious about their health.
Particularly, in the so-called advanced countries, the increasing
number of medical patients suffering from life-style related
diseases, including diabetes and hypertension imposes a serious
problem on the society.
[0003] For example, diabetic patients have to be dosed with
insulin. Conventionally, it is a general practice to inject insulin
to a diabetic patient after each meal. Dosing insulin by means of a
syringe forces pain on the part of the patient. To solve this
problem, dosing a medicine by way of the respiratory system of the
patient has been discussed. Generally three techniques of dosing a
medicine are known to date. They include the use of a metered dose
inhaler, the use of a dry powder inhaler and the use of an
atomizer.
[0004] Metered does inhalers (MDIs) are being widely used to treat
asthma. An MDI is provided with a valve for ejecting a dose of
aerosol in operation. The apparatus main body can be downsized for
the convenience of portability, although each dose can vary to a
considerable extent. Additionally, the user of an MDI is required
to operate the valve and inhale the dose in a considerably
synchronized manner. and many users feels the synchronized
operation of the MDI difficult and cumbersome.
[0005] The user of a dry powder inhaler (DPI) is required to inhale
a large volume of air in order to effectively apply dry powder to
the inside of the bronchus system of the user with a sufficient
degree of fluidity. While dry powder inhalers may be free from the
above-described problem of synchronizing the valve operation and
the inhalation of the dose, it is a considerable burden for the
user of a dry powder inhaler to inhale a large volume of air.
Additionally, patients who are sensitive to moisture and also to
the inhaled powder cannot use a DPI because the patient can burst
into a fit of asthma. Additionally, since the power for inhaling
air varies from person to person, the dose can vary also from
person to person.
[0006] An atomizer is adapted to generate aerosol by atomizing
liquid by means of a carrier gas flow. It requires a gas compressor
that operates continuously or a large volume of compressed gas for
its operation. Generally, the size of aerosol droplets is a
function of the pressure and the velocity of carrier gas and hence
it is not easy to independently change the concentration of the
medical agent, in a gas flow. Additionally, as the patient inhales
the atomized liquid, the pressure in the nozzle of the atomizer
falls. In other words, the dose and the particle size of the
medical agent are affected by the period and the strength of each
breathing action.
[0007] Thus, the above-described known apparatus are accompanied by
the problem of a low degree of precision of applying a right dose
of a medical agent of right particle size to a right position of
the patient body. In other words, they can be used only for medical
agents that show a large tolerance in terms of dose. In any case,
currently, it simply relies on the technique of the user for
applying a right dose to a right position.
[0008] On the other hand, there is a demand for improved medicinal
administration systems that can be used to optimally cure diseases
of the nose and those of the lung by means of a medical agent that
works only locally. Additionally, it has been proved as a result of
the advancement of medicine in recent years that application of a
medical agent such as protein, peptide or an analgesic to the lungs
is advantageous if compared with conventional administration
techniques such as oral administration and injection. However,
known inhalers cannot be used for such applications because they
are accompanied by the problem of variable particle size and that
of variable dose.
[0009] These problems will be described in greater detail by way of
examples. Of the current diabetic patients, whose number is
increasing, those suffering from insulin dependent diabetes
mellitus, which is also referred to as type I diabetes mellitus, do
not secrete insulin from the pancreas and hence insulin has to be
administered periodically to them.
[0010] Currently, administration of insulin is realized by means of
subcutaneous injection to impose a great physical and mental burden
on the patient. Pen-type syringes designed to use a very thin
needle have been developed to significantly reduce the pain on the
part of the patient. However, many patients suffering from type I
diabetes mellitus are working like healthy people unless insulin
has to be administered periodically to them and it will be mentally
difficult for such a patient to inject insulin to him- or herself
by means of a syringe while he or she is exposed to the public if
the syringe is of the pen-type.
[0011] Thus, there is a demand for an easy method of administering
a medical agent by the patient him- or herself that does not
involve the use of a syringe but can eject the medical agent in the
form of droplets and drive them to reliably reach the lungs.
[0012] Recently, there have been proposed methods for ejecting a
physiologically effective medical agent by a predetermined number
of droplets of proper size from a discharge orifice into an airflow
to be inhaled through a mouthpiece or the like under the effect of
a bubble jet or a piezoelectric element arranged in an ejection
head section (ejecting section) (see International Publication
WO95/01137 and International Publication WO02/04043).
DISCLOSURE OF THE INVENTION
[0013] The proposed apparatus make it possible to eject droplets of
uniform size. However, since the ejection head section of the
apparatus is directly subjected to negative pressure that is
produced by the atmospheric pressure as pressure difference at the
time of inhalation, liquid can leak from the orifice also at the
time of inhalation. When liquid leaks, it is not turned into
droplets of proper size and liquid is no longer ejected from the
clogged orifice. Then, it is no longer possible to eject droplets
by a predetermined quantity. Additionally, the ejection head
section is directly subjected to negative pressure to curtail the
service life of the ejection head section. Thus, the proposed
apparatus can hardly find practical applications.
[0014] In view of the above-identified problems, it is therefore
the object of the present invention to provide an inhaling
apparatus to be used by a user to inhale a liquid medical agent
from an inhalation port thereof, the apparatus comprising: a liquid
medical agent ejecting section having an ejection port for ejecting
a liquid medical agent as droplets; and a pressure detecting
section for detecting the negative pressure produced by the
atmospheric pressure as pressure difference at the time of
inhalation of the user for the purpose of controlling the ejection
of droplets from the ejection port; the ejection port of the liquid
medical agent ejecting section being arranged at a position
producing a pressure difference smaller than the pressure
difference with the atmospheric pressure as detected by the
pressure detecting section at the time of inhalation.
[0015] In another aspect of the present invention, there is
provided a mouthpiece to be removably fitted to an inhaling
apparatus according to the invention to form a flow path for an
airflow between an inhalation port and an external air intake port,
the mouthpiece comprising: pressure alleviating means arranged on
the halfway of the flow path to alleviate the negative pressure of
the ejecting section; a part (e.g., a communication hole
communicating with a negative pressure sensor, which will be
described hereinafter) for receiving the pressure detecting section
to be arranged therein, the part being arranged closer to the
inhalation port than the pressure alleviating means; and a part
(e.g., a liquid medical agent intake port, which will be described
hereinafter) for receiving the ejection port of the liquid medical
agent ejecting section to be arranged therein, the part being
arranged closer to the external air intake port side than the
pressure alleviating means.
[0016] In still another aspect of the present invention, there is
provided an inhaling apparatus to be used by a user to inhale a
liquid medical agent from an inhalation port thereof, the apparatus
comprising: a flow path for forming an airflow by means of an
inhaling action of a user, the flow path having the inhalation port
at an end thereof; a liquid medical agent ejecting section having
an ejection port arranged in the flow path to eject the liquid
medical agent as droplets; and a pressure detecting section
arranged in the flow path for detecting the negative pressure
produced by the atmospheric pressure as pressure difference at the
time of an inhaling action of the user; the ejection port of the
liquid medical agent ejecting section being arranged at a position
adapted to produce a pressure difference smaller than the pressure
difference with the atmospheric pressure as detected by the
pressure detecting section at the time of the inhaling action.
[0017] Thus, according to the present invention, since the ejection
port of the liquid medical agent ejecting section is arranged at a
position where the pressure difference with the atmospheric
pressure is smaller than the pressure difference detected by the
pressure detecting section at the time of inhalation, the risk of
liquid leakage from the ejecting section is minimized to by turn
minimize the adverse effect of leaking liquid on the service life
of the ejecting section.
[0018] Other features and advantages of the present invention will
be apparent from the following description taken in conjunction
with the accompanying drawings, in which like reference characters
designate the same or similar parts throughout the figures
thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a schematic perspective view of an example of
inhaler or inhaling apparatus according to the present
invention;
[0020] FIG. 2 is a schematic perspective view of the inhaling
apparatus of FIG. 1 in a state where the access cover is
opened;
[0021] FIG. 3 is a schematic perspective view of an example of the
CRG unit;
[0022] FIG. 4 is a schematic cross sectional view of an example of
mouthpiece taken along a lateral surface thereof;
[0023] FIG. 5 is a schematic cross sectional view of the mouthpiece
of FIG. 4 taken along the front surface thereof;
[0024] FIG. 6 is a schematic cross sectional view of the mouthpiece
of FIG. 4, illustrating the position relation with the negative
pressure sensor and the ejection head section of the CRG unit;
[0025] FIG. 7 is a schematic cross sectional view of the inhaler or
inhaling apparatus of FIG. 1, showing the entire apparatus;
[0026] FIG. 8 is a graph illustrating an inhaling operation of the
inhaler or inhaling apparatus of FIG. 1;
[0027] FIG. 9 is a flow chart of the overall operation of the
inhaler or inhaling apparatus of FIG. 1;
[0028] FIG. 10 is a schematic cross sectional view of Embodiment 2
of the present invention, which is a parallel flow paths type,
showing the configuration of the mouthpiece and its vicinity;
and
[0029] FIGS. 11A and 11B are schematic cross sectional view of
Embodiment 3 of the present invention comprising a valve,
illustrating its operation.
BEST MODE FOR CARRYING OUT THE INVENTION
[0030] Preferred embodiments of the present invention will now be
described. An embodiment of inhaling apparatus or inhaler according
to the invention is designed to be carried by the user. It
comprises a memory means for storing personal information of the
user, including information on the medical chart and the medical
prescription of the user. It is designed to eject micro-droplets of
a liquid medical agent by a predetermined amount so as to have the
user inhale the agent. The micro-droplets are highly uniform in
terms of their sizes. With this embodiment, the user can put a
mouthpiece, which has an inhalation port by way of which the user
can inhale the liquid medical agent, and an ejection head cartridge
(CRG) unit to an inhaler main body. The ejection head cartridge
unit includes a tank containing the agent and is adapted to eject
the agent supplied from the tank as micro-droplets. Thus, the user
can efficiently and hygienically inhale the liquid medical agent
according to the information provided by the prescription.
[0031] The flow path for establishing an airflow in the entire
inhaler is formed only by the mouthpiece. The mouthpiece is
provided on the halfway thereof with a narrowed section that
operates as a pressure alleviating means. A pressure detecting
section is arranged at a position closer to the user than the
narrowed section (at the side close to the inhalation port) to
detect the pressure there and the ejecting section of the CRG unit
is arranged at a position closer to the external air intake port
than the narrowed section. The liquid medical agent can flow out
through the ejection port to clog the ejection port when negative
pressure higher than a predetermined level (e.g., higher than -0.3
KPa (or greater than an absolute value of 0.3)) is applied to the
ejection head section. Then, the liquid medical agent will not be
ejected properly thereafter. However, the narrowed section prevents
the ejection head section from being directly subjected to the
negative pressure generated when the user inhales the liquid
medical agent so that micro-droplets are continuously and smoothly
ejected from the ejection port of the ejection head section. In
other words, the ejection port of the ejecting section is arranged
at a position where the pressure difference from the atmospheric
pressure that is produced at the time of inhalation is such that
the liquid medical agent would not be ejected naturally from the
ejection port by the negative pressure produced by the atmospheric
pressure so that micro-droplets of the agent are ejected smoothly.
Micro-droplets of the liquid medical agent may be ejected in any
mode of operation so long as they are ejected through an orifice.
For example, thermal energy, piezoelectric energy or energy
produced by pressurizing liquid may be utilized to eject
micro-droplets through an orifice. However, the use of an ink-jet
system, which may be a bubble jet system or a piezo jet system, is
preferable. When an ink-jet system is used, liquid is supplied from
a tank that is exposed to the atmosphere by the capillary force of
a nozzle so that environmental pressure needs to be found within a
range that allows the negative pressure produced by the tank and
the meniscus of the ejection port to be well balanced with each
other. From this point of view, the use of the arrangement of the
present invention is very effective.
[0032] As shown in FIG. 8, an ejecting operation from the ejection
port starts when the pressure detecting section detects negative
pressure of a predetermined level. However, the lowest negative
pressure that the pressure detecting section detects needs to be
defined appropriately because the negative pressure produced in the
pressure detecting section as a result of inhalation can vary from
person to person and generally relates to the breathing capacity of
the lungs. Considering about children and senior persons having a
relatively small breathing capacity, the cross sectional area of
the narrowed section is preferably defined to be about 10 mm.sup.2
so that the negative pressure may be higher than -0.5 Kpa (or
greater than an absolute value of 0.5). Then, it is possible for
the pressure detecting section to accurately observe changes in the
negative pressure produced as a result of inhalation (inhalation
curve as shown in FIG. 8).
[0033] Since the flow path for establishing an airflow in the
entire inhaler is formed only by the mouthpiece, the airflow
section is contaminated by the liquid medical agent only in the
flow path of the mouthpiece. In other words, the inside of the
inhaler is held safe and hygienic only by washing the
mouthpiece.
[0034] The efficiency of inhalation can be improved when more
liquid medical agent is brought into the lungs of the user by
changing some or all of the parameters (ejection speed, ejection
time, etc.) relating to the ejection of the liquid medical agent
typically according to the inhaled quantity (in other words
depending on the change of the inhalation curve as shown in FIG. 8
that is detected by the pressure detecting section). When an
inhaler according to the invention is equipped with an ejection
control means that is adapted to change some or all of the
parameters relating to the ejection of the liquid medical agent
depending on to the change in the flow rate for inhalation (the
change in the negative pressure) as detected by the negative
pressure sensor within a predetermined time period for which the
user inhales the liquid medical agent, it may additionally provided
with a notification means that operates when the user could not
inhale a predetermined quantity of the liquid medical agent within
the predetermined time period so as to notify the user that he or
she needs to inhale the liquid medical agent once again. Such an
embodiment is easy to use because it minimizes cumbersome
operations that have to be carried out by the user. Thus, such an
embodiment can be used by anyone at anywhere.
[0035] An inhaling apparatus according to the invention may
alternatively be configured in a manner as described below.
[0036] A valve that constantly and substantially closes the flow
path of an airflow except when the apparatus is operated for
inhalation may be used for the pressure alleviating means. Then,
the pressure detecting section is arranged at a position closer to
the inhalation port than the valve and the ejection port of the
ejecting section is arranged at the opposite side of the valve. As
the apparatus is operated for inhalation, the valve that has been
closed starts opening. Then, the negative pressure is alleviated
before it gets to the ejection port of the ejecting section located
at the side opposite to the inhalation port at a slightly delayed
timing so that the valve operates as a pressure alleviating
means.
[0037] Still alternatively, the pressure detecting section and the
ejection port of the ejecting section may be so arranged as to face
respective flow paths coming from the inhalation port. With this
arrangement, one flow path has its exit at the inhalation port,
which inhalation port is formed around the exit of the flow path to
show a profile similar to that of the mouth of human being and have
a part forming another flow path. The pressure detecting section
(with a communication hole communicating with the negative pressure
sensor) is arranged as facing the another flow path.
[0038] Still alternatively, an inhaler according to the invention
may be provided with a means for monitoring the inhaled quantity,
utilizing the negative pressure sensor, (in other words, monitoring
the inhalation curve as shown in FIG. 8) and notifying the user if
the inhaled quantity is appropriate or not by flashing an LED or by
changing the mode of vibration of a vibratory motor. Further, the
inhaler comprises a means for notifying the user of the inhalation
time period from the start of inhalation and when the inhalation
should be stopped. As for the means for notifying the inhalation
time period, a means that uses the vibration of the vibratory motor
can be used.
[0039] Thus, an inhaling apparatus according to the invention
having any of the above-described configurations can alleviate the
physical and mental burden imposed on the patient (user) and allow
the patient to inhale the (liquid) medical agent with ease.
Therefore, an inhaling apparatus according to the invention can
accurately control the patient's action of inhaling the medical
agent according to the prescription and feed a greater amount of
medical agent to the lungs than ever to improve the efficiency of
inhalation so as to efficiently administer the medical agent by
changing the drive parameters relating to the ejection of the
liquid medical agent according to the quantity of the medical agent
inhaled by the patient.
[0040] Now, the present invention will be described in greater
detail by referring to the accompanying drawings that illustrate
preferred embodiments of the invention.
Embodiment 1
[0041] FIG. 1 is a schematic perspective view showing the outer
appearance of an inhaler according to the present invention.
Referring to FIG. 1, there are shown an inhaler main body 1, an
access cover 2 and a front cover 3, which constitute the housing of
the inhaler. In FIG. 1, reference symbol 5 denotes a lock lever
urged by a spring and having a claw-like part at the front end
thereof that engages with a projecting section 2a arranged at the
front end of the access cover 2 in order to prevent the access
cover 2 from opening in operation. As the lock lever is driven to
slide downward, the access cover 2 is turned around a hinge pivot
(not shown) to become open by the resilience of the access cover
returning spring (not shown) that urges the access cover 2. In FIG.
1, reference symbol 101 denotes a power supply switch and reference
symbol 102 denotes a display LED which indicates that an ejection
head cartridge (CRG) unit or a mouthpiece, which will be described
in greater detail hereinafter, is not mounted in the housing or
that the tank of the CRG unit is empty and no liquid medical agent
is contained therein.
[0042] FIG. 2 is a schematic perspective view of the inhaler of
FIG. 1 in a state where the access cover 2 is opened. As the access
cover 2 is opened, the CRG unit 6 and the mouthpiece 4 that are
mounted in the housing along a CRG guide 20 are exposed. The
mouthpiece 4 is located under the CRG unit 6. They are mounted so
as to be transversal relative to each other. FIG. 3 is a schematic
perspective view of the entire CRG unit 6. The CRG unit 6 comprises
a tank 7 for containing a liquid medical agent, a head section
(ejecting section) 8 for ejecting the liquid medical agent, a part
(electrically connecting section) 9 having an electric connection
surface for supplying electric power from battery 10 (see FIG. 7)
to cause the heater arranged in the head section 8 to generate
thermal energy and so on. The battery 10 is rechargeable and
operates as secondary cell for storing electric power in the inside
of the inhaler in order to cause the heater to generate thermal
energy. The front surface section of the CRG unit 6 can be opened
around a hinge section 24 to allow access to the tank 7. A
projection is typically formed on the rear surface of the front
surface section so that the projection forcibly moves into the tank
7 and slightly applies pressure to the liquid medical agent in the
tank 7 to refresh the ejection port of the head section 8 at the
moment that the front surface section is closed.
[0043] FIGS. 4 and 5 are schematic cross sectional views of the
mouthpiece 4. The mouthpiece 4 alone forms an airflow path and is
provided at a part located close to its air intake port 11 with a
window (liquid medical agent intake port) 12 for taking the liquid
medical agent from the ejection port of the head section 8 of the
CRG unit 6 into the inside of the mouthpiece 4. A narrowed section
4a is formed on the halfway of the mouthpiece 4 so as to gradually
reduce the cross sectional area. As shown in FIG. 6 in detail, an
air hole 13 is bored at a part of the flow path where the cross
sectional area increases from that of the narrowed section 4a so as
to make the flow path communicate with the measuring hole of a
negative pressure sensor 19 for detecting the rate of inhalation or
the inhaled quantity that is the value of the integral of the rate
of inhalation by detecting the negative pressure there. The
negative pressure sensor 19 is arranged on a control substrate 21
(see FIGS. 6 and 7). An expanded space 22 is arranged on the
halfway of the flow path between the air hole 13 and the negative
pressure sensor 19. The expanded space 22 operates as pool for
storing dirt, dust, water drops and the liquid medical agent in
order to prevent them from entering through the air hole 13 and
adhering to the surface of the negative pressure sensor 19 so that
the inhaler may not operate improperly.
[0044] A mouthpiece exit (inhalation port) 15 is formed at the end
of the mouthpiece 4 opposite to the air intake port 11 so as to
show a profile adapted to be held in the mouth of the user. The
mouthpiece exit 15 shows an elliptic cross section that matches the
profile of the mouth of human being. The inside of the mouthpiece 4
has a dual structure and a flow path exit 14 is formed to allow the
liquid medical agent to pass through the inside. The flow path exit
14 is so formed as to show a profile that makes its cross sectional
area gradually increase because, if the exit increases its cross
sectional area suddenly, the mixed fluid of air and the liquid
medical agent can be expanded abruptly to adhere to some of the
teeth of the user who is holding the mouthpiece exit in his or her
mouth. Thus, the user is suggested to allow the end of the flow
path exit 14 to slightly pass through his or her teeth when holding
the mouthpiece exit 15 in the mouth. The end of the flow path exit
14 may be so formed as to slightly extend outward beyond the end of
the mouthpiece exit 15 so that the user can allow the end of the
flow path exit 14 to pass through the teeth with ease. As shown in
FIGS. 1 and 2, the airflow path of the mouthpiece 4 shows a
rectangular cross section so that the mouthpiece 4 can be mounted
in the housing with the air intake port 11 reliably directed
upward.
[0045] FIG. 7 is a schematic cross sectional view of this
embodiment of inhaling apparatus, showing the entire apparatus. A
control substrate 21 for controlling the inhaler is arranged below
the battery 10. The control substrate 21 is connected to a probe
substrate 16 by way of a cable or a connector (a connector 25 is
used in FIG. 7), which probe substrate 16 is arranged below the CRG
unit 6. A contact probe 17 is also arranged to connect the probe
substrate 16 and the electrically connecting section 9 of the CRG
unit 6 and electrically energize the head section 8 of the CRG unit
6 for the purpose of emission of heat. A vibration motor 18 is
arranged in contact with the control substrate 21 in the space
between the battery 10 and the mouthpiece 4.
[0046] Now, the operation of inhalation of this embodiment having
the above-described configuration will be described by referring to
FIG. 8.
[0047] As the user starts inhalation and the negative pressure
(relating to the rate of inhalation or the flow rate) detected by
the negative pressure sensor 19 reaches a level that allows
ejection of the liquid medical agent to take place, the inhaler
starts ejecting the liquid medical agent from the head section 8 of
the CRG unit 6 under the control of the control substrate 21 and
the vibration motor 18 starts vibrating at the same time to notify
the user that the inhaler start ejecting the liquid medical agent.
After the end of ejection of a predetermined quantity from the head
section 8, the vibration motor 18 keeps on vibrating for a
supplementary inhalation time that is determined on the basis of
the rate of inhalation and the continuous inhalation time as
computed from the negative pressure value of the negative pressure
sensor 19 for the purpose of encouraging the user to inhale a
quantity for supplementary inhalation and so that the ejected
liquid medical agent may completely reach the lungs. As the
vibration motor 18 stops vibrating, the user, or the patient, stops
inhaling the liquid medical agent. With this arrangement, the
process of ejecting the liquid medical agent and that of inhalation
are interlocked with each other so that the liquid medical agent is
reliably fed into the lungs to avoid a failure of insufficient
inhalation.
[0048] As the result of the inhaling action of the user, air is fed
into the mouthpiece 4 from the air intake port 11 to produce a
mixed fluid of air and the liquid medical agent ejected from the
ejection port arranged in the head section 8 of the CRG unit 6. The
mixed fluid is then led to the mouthpiece exit 15 having a profile
adapted to be held in the mouth of the user. The mouthpiece exit 15
is adapted to prevent the mixed fluid from leaking through the
lateral ends of the mouth, minimizing the waste of the mixed fluid,
and cause the mixed fluid to hardly collide with the obstacles in
the mouth such as teeth so that the liquid medical agent may be
efficiently inhaled into the body of the user.
[0049] This embodiment is provided with the vibration motor 18
because the user may not want to be known about his or her use of
the inhaler and vibrations may be more preferable than sounds to
the user as notification means. Thus, with this arrangement, the
embodiment can be used by anyone at anywhere.
[0050] An example of overall operation of the inhaling apparatus
will be described below by referring to the flow chart of FIG. 9.
As the power supply switch 101 is turned on, the open or closed
state of the access cover 2 is detected (S801). If the access cover
2 is open, the user is warned about it typically by means of the
display LED 102. If it is closed, it is then detected if a CRG unit
6 is mounted or not (S802). In the example, if a CRG unit 6 is not
mounted, a Bluetooth communication is started (S803) to exchange
data with the user, including data on the quantity to be
administered to the user (S804). The operation ends when the
communication is completed (S805). This mode of operation may be
utilized mainly by the doctor of the user.
[0051] If, on the other hand, a CRG unit 6 is mounted, the
operation proceeds in a manner as described below. This mode of
operation may be utilized mainly by the patient, or the user. As
the user starts inhalation (S806) and the inhalation is detected,
negative pressure is detected by the negative pressure sensor 19
when it reaches a predetermined level (S807). Then, the ejection
head section 8 starts ejecting the liquid medical agent (S808). If
it is not detected that negative pressure reaches a predetermined
level, a warning for prompting the user to inhale harder may be
issued.
[0052] The liquid medical agent is ejected for a predetermined time
period after the start of ejection so that a predetermined quantity
of the liquid medical agent may be ejected. The quantity is
determined on the basis of the data read in by the inhaling
apparatus. Subsequently, the negative pressure sensor 19 monitors
the change with time of negative pressure due to inhalation and the
inhaling apparatus detects if the predetermined quantity has been
inhaled or not on the basis of the value of the integral of the
change with time (S809). The time for starting the integral may be
selected appropriately. Since the integrated value relates to the
inhaled quantity of the mixed fluid of air and the liquid medical
agent, it corresponds to detecting if the liquid medical agent has
been inhaled by the predetermined quantity. The operation ends when
the liquid medical agent has been inhaled by the predetermined
quantity. Then, the vibration motor 18 stops vibrating. If it is
not detected that the liquid medical agent has been inhaled by the
predetermined quantity after the elapse of a predetermined time
period, a warning is issued to the user typically by means of a
change in the mode of vibration of the vibration motor 18 in order
to prompt the user to inhale the liquid medical agent again (S806).
In such a case, the quantity short of the quantity to be inhaled is
computed (S810) and the quantity of the liquid medical agent to be
ejected from the ejection head section 8, the inhalation time
period (or the vibration time period of the vibration motor 18) and
other necessary values are computationally determined
accordingly.
[0053] Since the ejection port of the liquid medical agent ejecting
section is arranged reliably at a position where the pressure
difference with the atmospheric pressure is smaller than the
pressure difference detected by the pressure detecting section at
the time of inhalation in the above described embodiment, the risk
of liquid leakage from the ejecting section is minimized to by turn
minimize the adverse effect of leaking liquid on the service life
of the ejecting section. Furthermore, the liquid medical agent is
reliably and efficiently administered to the user by a
predetermined quantity by way of a simple operation.
Embodiment 2
[0054] FIG. 10 is a schematic cross sectional view of Embodiment 2
of the present invention, which differs from Embodiment 1 only in
terms of the configuration of the flow path to the pressure
detecting section (the communication hole 13 communicating with the
negative pressure sensor 19). In Embodiment 2, the communication
hole 13 is arranged to the outside of the flow path exit 14 of the
mouthpiece exit 15 located at the front end of the mouthpiece 4.
With this arrangement, a negative pressure detecting flow path led
to the negative pressure sensor 19 is completely separated from and
arranged in parallel with the airflow path of the mouthpiece 4.
When the mouthpiece 4 is mounted in the apparatus from the upper
and front surface thereof, the mounting direction agrees with the
direction in which the communication hole 13 comes tightly close to
the negative pressure detecting flow path led to the negative
pressure sensor 19. Thus, this arrangement is advantageous for
preventing air from leaking. Then, negative pressure is reliably
detected. Additionally, since the negative pressure detecting flow
path led to the negative pressure sensor 19 and the liquid medical
agent flow path are completely separated from each other, the
negative pressure detecting flow path is minimally contaminated by
the liquid medical agent to ensure a highly accurate detection of
negative pressure. Otherwise, Embodiment 2 is identical with
Embodiment 1.
Embodiment 3
[0055] FIG. 11A and 11B show Embodiment 3 comprising a pressure
alleviating means that is different from the narrowed flow path of
Embodiment 1. A valve 30 having a size substantially same as the
cross sectional area of the flow path of the mouthpiece 4 is
rotatably arranged between the communication hole 13 led to the
negative pressure sensor 19 and the liquid medical agent intake
port 12 receiving the ejection head section 8 in the flow path of
the mouthpiece 4. The valve 30 is constantly held to state where it
substantially closes the flow path as it is made to abut a valve
stopper 31 as illustrated in FIG. 11A. The valve 30 is opened as
shown in FIG. 11B when the user starts an inhaling operation. While
relatively strong negative pressure is generated in the flow path
space at the side of the negative pressure sensor 19 at this time,
such strong negative pressure is not generated in the flow path
space at the side of the ejection head section 8. Thus, the net
results will be same as those of Embodiment 1. Otherwise,
Embodiment 3 is identical with Embodiment 1.
[0056] The present invention is not limited to the above
embodiments and various changes and modifications can be made
within the spirit and scope of the present invention. Therefore, to
apprise the public of the scope of the present invention, the
following claims are made.
[0057] This application claims priority from Japanese Patent
Application No. 2004-225510 filed on Aug. 2, 2004, which is hereby
incorporated by reference herein.
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