U.S. patent application number 12/008565 was filed with the patent office on 2008-05-15 for system, combination and method for controlling airflow in convective treatment.
Invention is credited to Randall Charles Arnold, Scott Douglas Augustine, Gary Rabindranath Maharaj, John Paul Rock, Albert Philip Van Duren, Allen Hamid Ziaimehr.
Application Number | 20080113608 12/008565 |
Document ID | / |
Family ID | 26698384 |
Filed Date | 2008-05-15 |
United States Patent
Application |
20080113608 |
Kind Code |
A1 |
Van Duren; Albert Philip ;
et al. |
May 15, 2008 |
System, combination and method for controlling airflow in
convective treatment
Abstract
In a convective system that includes a blower to thermally treat
and pressurize air, a convective device to receive and convect the
thermally-treated pressurized air, and an air hose to conduct a
flow of thermally-treated pressurized air from the blower to an
inlet port in the convective device, an interface device is
provided to control the flow of air at the interface where the
inlet port and an end of the air hose operate to conduct the flow
of air out of the air hose into the convective device. The
interface device is received at the end of the air hose and
operates to support the flow of air out of the end when the end and
the inlet port are brought together. The interface device operates
to stop, inhibit, or restrict the flow of air out of the end when
the end and the inlet port are separated.
Inventors: |
Van Duren; Albert Philip;
(Chaska, MN) ; Ziaimehr; Allen Hamid; (Arden
Hills, MN) ; Rock; John Paul; (Minneapolis, MN)
; Augustine; Scott Douglas; (Bloomington, MN) ;
Maharaj; Gary Rabindranath; (Eden Prairie, MN) ;
Arnold; Randall Charles; (Minnetonka, MN) |
Correspondence
Address: |
TERRANCE A. MEADOR;INCAPLAW
1050 ROSCRANS STREET, SUITE K
SAN DIEGO
CA
92106
US
|
Family ID: |
26698384 |
Appl. No.: |
12/008565 |
Filed: |
January 11, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10131068 |
Apr 23, 2002 |
7338515 |
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12008565 |
Jan 11, 2008 |
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10024387 |
Dec 17, 2001 |
7220273 |
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10131068 |
Apr 23, 2002 |
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Current U.S.
Class: |
454/237 |
Current CPC
Class: |
A61F 7/00 20130101; A61H
2033/061 20130101; A61F 2007/006 20130101; A61H 2203/0456 20130101;
F24F 7/065 20130101; A47C 21/04 20130101; A61F 7/0097 20130101;
A61H 33/06 20130101; F24F 2011/0004 20130101; A61F 2007/0055
20130101 |
Class at
Publication: |
454/237 |
International
Class: |
F24F 7/007 20060101
F24F007/007 |
Claims
1. A system for controlling airflow in convective treatment,
comprising: a blower; an air hose with a first end receivable in
the blower and a second end; a convective device with an inlet port
to receive pressurized air from the second end; and, an interface
device mounted to the second end and receivable by the inlet port,
the interface device including a shutter slidably disposed near the
second end and moveable between a first position where the shutter
prevents the flow of air out of the second end and a second
position where the shutter permits the flow of air out of the
second end.
2. The system of claim 1, wherein the interface device acts between
the inlet port and the second end to keep the shutter in the first
position when the interface device is received by the inlet
port.
3. The system of claim 1, the interface device further including: a
tubular end piece with two ends, a first end of the tubular end
piece receivable on the second end of the air hose: a front piece
disposed on the second end of the tubular piece; a surface on the
front piece, the surface having a periphery; a frame on the
surface, with slots disposed around the periphery; and, an opening
in the surface; the shutter being retained in the slots so as to
slide on the surface, over the opening.
4. The system of claim 3, wherein the frame is a concave
rectangular frame, the surface is a concave rectangular surface,
and the shutter is a flexible shutter.
5. The system of claim 3, wherein the frame is a concave
rectangular frame, the surface is a concave rectangular surface,
and the shutter has a shape that fits the shape of the concave
rectangular surface.
6. The system of claim 3, the interface device further including a
retainer disposed on the shutter to engage the inlet port so as to
keep the shutter in the second position.
7. The system of claim 3, the shutter including first and second
portions, the first portion being unbroken, and the second portion
including at least one opening, such that when the shutter is in
the first position, the first portion covers the opening in the
surface, and when the shutter is in the second position, the at
least one opening in the shutter is aligned with the opening in the
surface.
8. The system of claim 7, the interface device further including: a
slot in the surface, disposed generally on a longitudinal axis of
the surface; a gudgeon disposed on the shutter to face the slot in
the surface; and, a spring acting between the slot in the surface
and the gudgeon; the spring being compressed by the slot and the
gudgeon when the shutter is in the second position.
9. The system of claim 8, the interface device further including: a
cover disposed on the frame such that the shutter is sandwiched
between the surface and the cover; an opening in the cover aligned
with the opening in the surface; a slot in the cover extending to
the opening in the cover; a retainer disposed on the shutter to
move in the slot in the cover as the shutter moves between the
first and second positions.
10. The system of claim 9, wherein the retainer is positioned on
the shutter to engage the inlet port, thereby to retain the shutter
in the second position, with the spring compressed.
11. The system of claim 10, wherein the shutter is returned to the
first position by the compressed spring acting against the gudgeon
when the retainer is released from the inlet port.
12. The system of claim 10, wherein the shutter is returned to the
first position by the compressed spring acting against the gudgeon
when the interface device is removed from the inlet port.
13. The system of claim 7, further including means for moving the
shutter to the first position when the interface device is removed
from the inlet port and for retaining the shutter in the second
position when the interface device is received by the inlet
port.
14. An interface device for controlling airflow delivered by an air
hose to an inlet port of a convective thermal treatment apparatus,
comprising: a tubular end piece with first and second ends, the
first end being receivable on the air hose; a front piece disposed
on the second end and receivable in the inlet port; a surface on
the front piece, the surface having a periphery; a frame on the
surface, with slots disposed around the periphery; and, an opening
in the surface; the shutter being retained in the slots so as to
slide on the surface, over the opening, between a first position
where the shutter blocks the opening in the surface in response to
the interface device being removed from the inlet port and a second
position where the shutter opens the opening in the surface in
response to the interface device being received in the inlet
port.
15. The interface device of claim 14, wherein the frame is a
concave rectangular frame, the surface is a concave rectangular
surface, and the shutter is a flexible shutter.
16. The interface device of claim 14, wherein the frame is a
concave rectangular frame, the surface is a concave rectangular
surface, and the shutter has a shape that fits the shape of the
concave rectangular surface.
17. The interface device of claim 14, further including a retainer
disposed on the shutter to engage the inlet port so as to keep the
shutter in the second position.
18. The interface device of claim 14, the shutter including first
and second portions, the first portion being unbroken, and the
second portion including at least one opening, such that when the
shutter is in the first position, the first portion covers the
opening in the surface, and when the shutter is in the second
position, the at least one opening in the shutter is aligned with
the opening in the surface.
19. The interface device of claim 18, further including: a slot in
the surface, disposed generally on a longitudinal axis of the
surface; a gudgeon disposed on the shutter to face the slot in the
surface; and, a spring acting between the slot in the surface and
the gudgeon; the spring being compressed by the slot and the
gudgeon when the shutter is in the second position.
20. The interface device of claim 19, further including: a cover
disposed on the frame such that the shutter is sandwiched between
the surface and the cover; an opening in the cover aligned with the
opening in the surface; a slot in the cover extending to the
opening in the cover; a retainer disposed on the shutter to move in
the slot in the cover as the shutter moves between the first and
second positions.
21. The interface device of claim 20, wherein the retainer is
positioned on the shutter to engage the inlet port, thereby to
cause the shutter to be retained in the second position and the
spring to be compressed.
22. The interface device of claim 21, wherein the shutter is
returned to the first position by the compressed spring acting
against the gudgeon when the retainer is released from the inlet
port.
23. The interface device of claim 18, further including means for
moving the shutter to the first position when the interface device
is removed from the inlet port and for retaining the shutter in the
second position when the interface device is received by the inlet
port.
24. A method for safely operating a convective thermal treatment
system, the method comprising: mounting an interface device with a
slidable shutter to an air hose; mounting the interface device to
an inlet port of a convective treatment device; in response to
mounting the interface device to the inlet port, sliding the
shutter to an open position permitting air flow from the air hose
to the inlet port; providing a flow of heated air through the air
hose to the inlet port; separating the interface device from the
inlet port; and then, sliding the shutter to a closed position
preventing air flow out of the air hose.
25. The method of claim 24, wherein sliding the shutter to the open
position includes compressing a spring in the interface device, and
sliding the shutter to the closed position includes the compressed
spring moving the shutter to the closed position in response to
separation of the interface device from the inlet port.
Description
PRIORITY AND RELATED APPLICATIONS
[0001] This is a divisional of U.S. patent application Ser. No.
10/131,068, which is a continuation-in-part of U.S. patent
application Ser. No. 10/024,387, filed Dec. 17, 2001, now U.S. Pat.
No. 7,220,273, which is incorporated herein by this reference.
[0002] U.S. patent application Ser. No. 10/024,387 claims priority
as a divisional of U.S. patent application Ser. No. 09/546,078, now
U.S. Pat. No. 6,447,538.
[0003] This application contains subject matter related to the
subject matter of U.S. patent application Ser. No. 09/138,774 filed
Aug. 24, 1998, now U.S. Pat. No. 6,126,681, and to its
continuation-in-part, U.S. patent application Ser. No. 09/546,078,
filed Apr. 10, 2000, now U.S. Pat. No. 6,477,538. Both of these
patent documents are incorporated herein by this reference.
FIELD OF THE INVENTION
[0004] This invention relates generally to forced-air convection
treatment of persons and, more particularly, to a system, a
combination, and a method for controlling airflow in convective
treatment in order to prevent injury to a person such as might
occur when thermally-conditioned (heated or cooled) air is
discharged directly onto the person.
BACKGROUND OF THE INVENTION
[0005] A convective treatment system consists of a
temperature-control/blower unit (known simply as a "blower"), a
ducting system, a convective device such as a convective warming
blanket, and/or an infusate heat exchanger. A blower aspirates air
from an ambient environment, changes its temperature to a desired
value, pressurizes the air above the ambient pressure, and
discharges the air at an exhaust port. U.S. Pat. No. 6,126,393
describes such a blower and associated temperature and noise
control schemes. In an exemplary convective treatment system,
pressurized, thermally regulated air produced by a blower is
conveyed through a ducting system and delivered to a convective
device, such as a convective warming blanket, that distributes the
thermally regulated air around a person or a specific body area of
a person. A person can be a human being, animal, or thing. In some
applications, a blower unit may be used to operate other accessory
devices with or without a convective device. In these stand-alone
applications, the blower unit may be used to warm infusates, such
as blood or saline, through the use of a heat exchanger adapted to
fit within the duct system. U.S. Pat. No. 5,807,332 describes one
type of nonconvective device that is used to warm infusates for
administration into persons. The use of an infusate warmer does not
preclude the concomitant use of a convective device; however, the
distal end of the air supply duct is covered with an air diffuser
during the exclusive use of an infusate warmer. The user must
intentionally place the diffuser over the distal end of the air
supply duct. The diffuser allows the heated air to escape from the
distal end of the air supply duct but prevents the heated air from
striking the patient directly.
[0006] A convective device may be embodied, for example, in an
inflatable device which inflates with pressurized, thermally
regulated air and has one or more surfaces adapted for expelling
air onto a person. Such devices may lie on, around, or under the
person. A convective device is generally realized as a blanket, but
can be embodied by other appliances or attachments that are
designed to be operated by or with the application of pressurized,
thermally conditioned air. When used herein, the term "convective
device" is intended to include all blankets, pads, covers,
manifolds, and equivalent structures that operate as just
described. Irrespective of orientation, a convective device
utilized for convective thermal treatment of persons performs at
least three basic functions. These functions are 1) the conveyance
of thermally conditioned air from at least one inlet port into the
device, 2) the imposition of a heat gain or loss that changes the
temperature of the thermally conditioned air, and 3) the
extravasation of the thermally conditioned air from the device. In
the following discussion, the assumption is that such a convective
treatment device is operated to warm a person by delivery of heat
to the person.
[0007] In those convective treatment systems which warm a person by
the application of heat, heat may be transferred by convection,
radiation, and conduction, but convection generally predominates at
the interface between the convective device and the person. The
rate of convective heat transfer depends on material properties,
surface boundary conditions, and significantly, fluid velocity.
[0008] Heat is lost from a convective treatment system whenever a
temperature gradient exists between it and the ambient environment.
During normal operation of the system, the temperature of the air
expelled onto the person is maintained at a level that is generally
higher than the person's skin surface temperature, but not high
enough to cause tissue damage. In order to counter the loss of heat
from the system, however, the air is heated initially to a
temperature that may exceed the thermal damage threshold at the
target site on the person's skin. Within certain limits, the amount
of heat lost from the system is predictable. This predictability
allows the system to operate safely by measuring and controlling
the temperature at the proximal end of the air supply duct that
connects the blower to the convective device. If any factors upon
which the assumption of predictability depends are altered,
however, the fluid temperature at the distal end of the duct system
may be affected.
[0009] Several intrinsic and extrinsic factors contribute to the
rate of heat loss from a convective treatment system. Among the
intrinsic factors are the surface area and material characteristics
of the duct and convective device, and the residence time of the
warmed air within the duct and convective device. Extrinsic factors
include, but are not limited to, ambient temperature and air
velocity in the area immediately adjacent to the duct and the
convective device. The residence time of the heated fluid within
the system is a function of its pressure and the resistance exerted
by the entire system. Factors that influence resistance are the
duct diameter and length, the orientation of the duct, and the
resistance of the convective device or devices.
[0010] One hazard associated with the use of convective treatment
is burns. First-, second-, and third-degree burns have occurred
through the improper use of convective treatment systems. The burn
hazard is accentuated by the intentional or accidental alteration
of the intrinsic or extrinsic factors that moderate the heat loss
in the system. The alteration of any of these factors introduces an
unpredictable amount of heat loss into the system, which can
significantly alter the temperature or velocity of the heated air
delivered to the person. One of the more important factors that
influence the temperature of warm air flowing out of the air supply
duct through the end where it connects to the convective device is
the residence time of the air within the duct. The end through
which air flows out of the air supply duct is usually referred to
as the "distal end" of the air supply duct. Typically, a nozzle may
be mounted to this end. The temperature of pressurized warm air
exiting the duct at this end is called "nozzle temperature"
(whether or not a nozzle is mounted thereto). In general, a
decrease in residence time of the pressurized warmed air is usually
associated with an increase in the nozzle temperature of the
air.
[0011] In the field, a common misuse of one or more components of a
convective treatment system occurs. Either intentionally or
accidentally, some users fail to connect the convective device to
the distal end of the duct and allow the heated air discharged from
the distal end to make direct contact with the person. In view of
the fact that an air supply duct is typically embodied as an air
hose, this practice has come to be known as "hosing" or
"free-hosing." In other cases, operators have failed to connect the
convective device to the duct and allowed the heated duct to make
direct contact with the person's skin. Users who have experienced
therapeutic misadventures through this type of misuse have reported
their experiences of thermal injuries to the FDA and the
manufacturers of the offending convective treatment systems. Some
manufacturers of have responded by warning and training users and
affixing labels to the thermal-control/blower units and convective
devices. Despite warnings, training, and labeling, however, persons
continue to be injured through misuse of warming devices.
[0012] The American Society for Testing and Materials (ASTM) has
recently circulated a draft standard (ASTM F29.19.01) from the
Subcommittee for Patient Warming Equipment entitled Standard
Specification for Circulating Liquid and Forced Air Patient
Temperature Management Devices. The members of the ASTM
subcommittee recognized the hazards associated with the practice of
free-hosing and developed requirements for equipment to limit skin
surface temperatures to 48.degree. C., or less, during any
operating or fault condition. Additionally, the standard requires
the manufacturers of thermal-control/blower units to affix a
cautionary statement to the distal end of the air supply duct that
warns the user against the practice of "free-hosing." Thus, the
ASTM standard explicitly recognizes the importance of air
temperature, and tacitly acknowledges the role of airflow, in
causing thermal burns.
[0013] Hosing causes at least four uniquely hazardous conditions to
exist: 1) The loss of the resistance from the lack of an convective
device leads to a decrease in the residence time of warmed air in
the air supply duct. As the warmed air has less time to cool in the
air supply duct, it arrives at the distal end of the duct at a
higher than normal temperature; 2) The lack of airflow resistance
from the absence of the convective device also leads to an increase
in the air velocity that is exhausted from the supply duct; The
relative increase in air velocity can lead to significantly higher
heat transfer rates if the air strikes the skin; 3) The lack of an
convective device makes it possible for the high temperature and
high velocity air to strike directly the person's skin over a very
small area. In essence, all, or most, of the heat energy intended
to be distributed over a large surface area is concentrated onto a
very small area; and 4) The lack of an convective device makes it
possible for the air supply duct itself to make direct contact with
the person's skin.
[0014] It is manifest that the hazards of hosing are not
intentionally visited on any victim. Nevertheless, it is the case
that large caseloads and near-crisis conditions can distract the
attention of those who are in charge of the immediate operation of
convective treatment systems. In such circumstances, the
practitioner may be unaware of the development of conditions that
pose a hazard of burns, or may be forgetful of known conditions
that require close and constant attention. Accordingly, significant
benefits would be realized by safety provisions that operate
automatically to reduce the risk of harm that can arise during the
operation of convective treatment systems. Especially desirable are
measures that would automatically mitigate the potential of burns
that might occur when the air supply duct is separated from the
convective device in a convective treatment system that delivers
warmed air for treatment.
[0015] The assignee of this application has designed safety
provisions that reduce the risk of burns by modulating the
operation of a blower in response to changes in the integrity of
the connection between the air duct and the convective device.
These provisions are set out in U.S. Pat. No. 6,126,681 and a
continuation-in-part thereof, U.S. patent application Ser. No.
09/546,078, both of which are incorporated herein by this
reference. However, these provisions must be implemented in the
structure and operation of a blower, and implicate redesign and
reconstruction of exiting blower architecture.
[0016] Accordingly, there is an immediate need for additional,
easily-implemented measures in convective treatment technology to
1) automatically mitigate a potentially unsafe condition
irrespective of an operator's awareness of the unsafe condition, 2)
prevent the intentional or unintentional misuse of convective
treatment system components by users who fail to connect the
appropriate convective devices to the distal end of the air supply
duct and thereby allow heated air to make direct contact to the
person, and 3) prevent the air supply duct from causing thermal
injury to the person if it makes direct contact with the person's
skin.
SUMMARY OF INVENTION
[0017] It is an object of this invention to automatically correct
the condition where an air supply duct that is still conducting
pressurized air is not connected to a convective device.
[0018] A further object of this invention is to correct the
condition in a way that does not interfere with the normal
operation of a convective device or an accessory device whenever
these devices are properly attached to the air supply duct.
[0019] The invention is based on the critical realization that the
there exists an interface in a convective treatment system where
measures can be implemented to reduce, if not stop, the flow of
heated air when the air supply duct is disconnected, uncoupled, or
detached from the convective device. The interface is where the
connection, coupling, or attachment of the air supply duct with the
convective device is made. At this interface, an interface device
is provided that reduces, restricts or stops the flow of air
through the end when the end is disconnected, uncoupled, or
detached from the convective device. The interface device may be
manually operated or self-actuating.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIGS. 1A and 1B illustrate a convective treatment system in
which the invention is deployed. FIG. 1B is a magnified partial
perspective view of a portion of a convective device where an inlet
port is located, with an end of an airhose positioned to e received
in the inlet port.
[0021] FIGS. 2A-2E illustrate an embodiment of an interface device
according to the invention.
[0022] FIGS. 3A-3E illustrate another embodiment of an interface
device according to the invention.
[0023] FIGS. 4A and 4B illustrate another embodiment of an
interface device according to the invention.
[0024] FIGS. 5A-5C illustrate another embodiment of an interface
device according to the invention.
[0025] FIGS. 6A and 6B illustrate another embodiment of an
interface device according to the invention.
[0026] FIGS. 7A and 7B illustrate another embodiment of an
interface device according to the invention.
[0027] FIGS. 8A-8C illustrate another construction of the
embodiment of FIGS. 7A and 7B.
[0028] FIGS. 9A and 9B illustrate another construction of the
embodiment of FIGS. 7A and 7B.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0029] In this description, a convective warming system will be
described, together with certain elements of such a system. The
elements will be denominated by terms that are selected for
syntactic convenience and utility in suggesting a structure or a
function. The terms are not selected, nor are they intended, to
constrain or limit the range of structural and functional
equivalents to which the elements, alone or in combination, are
entitled.
[0030] In this regard, the terms "blower" and "convective device"
are defined above. The term "air supply duct" is used in the
background to denote a tubular passage through which air is
pressurized by the blower and conducted from the blower to a
convective device in a convective treatment system. Hereinafter,
the term "air hose" will be used in place of "air supply duct" in
order to convey the sense of a flexible tubular passage. The air
hose has two ends, one for connection to the blower, the other for
connection to the convective device. For convenience of this
description, and for no other purpose, the end that is to be
connected to the convective device may also be called a "distal"
end. In the context of the invention, it is presumed that the air
hose conducts pressurized air that is warmed; indeed the air may
even be called "hot". This is intended to convey the sense that the
temperature of the air has the potential to be raised to a level in
a range, and that that level or any other level in the range
results in a nozzle temperature that poses a risk of harm to a
person if blown directly onto the person from the nozzle of the air
hose, with the convective device removed.
[0031] The term "interface device" is also used in this
description. In this application, an interface device is a device,
an apparatus, an appliance, or any equivalent structure or means,
that wholly or partly closes the distal end of an air hose in order
to reduce, restrict, attenuate, or even stop the flow of air out of
the air hose. One may also call an interface device a
"flow-restricting" member or a "closure", or a "stricture", or any
other equivalent term without narrowing or surrendering the full
range of equivalents that the term "interface device" is entitled
to. As will become apparent the interface device can perform these
functions without a nozzle being mounted to the end. Further, the
interface device may be received on a nozzle at the end, integrated
into the structure of a nozzle at the end, or may itself act also
as a nozzle at the end.
[0032] The term "inlet port" is used in this description as well.
Convective devices employ a variety of inlet port structures. In
this application, an inlet port is any component of a convective
device configured to allow for the ingress of pressurized air.
Inlet ports may come in the form of sleeves, sheets flexible of
material, and rigid material with defined openings.
[0033] Refer to FIGS. 1A and 1B in which a convective treatment
system 10 is illustrated. The elements of the system 10 include a
blower 12 that aspirates air from the ambient environment, raises
its temperature to a desired level, pressurizes the air above
ambient pressure, and discharges the heated, pressurized air at an
exhaust port 14. An air hose 16, with two ends, 18 and 20, is
provided. The end 18 is connected to the exhaust port 14 and the
air hose 16 conducts the heated, pressurized air to the end 20. The
end 20 is connected, coupled, or joined to the inlet port 22 of a
convective device 24. In this regard, the equivalent action from
the point of view of the convective device 24 is that the end 20 is
received in, or by, or near the inlet port 22. When the end 20 and
the inlet port 22 are thus brought together, the heated,
pressurized air is conducted through or out of the end 20 into the
convective device 24.
[0034] A representative convective device with an inlet port is
described in detail in the assignee's U.S. Pat. No. 6,309,408,
which is incorporated by this reference. The convective device 24
and its associated inlet port 22 may be understood with reference
to the '408 patent, in which an inflatable device has an opening
around which is mounted a relatively stiff sheet of cardboard
material. The sheet of cardboard material has an opening that is
aligned with the opening in the inflatable device. The sheet
provides structure to receive, retain and support the end or nozzle
of an air hose in an inlet port. This arrangement, shown in FIGS.
15 and 16 of the '408 patent, is instructive in understanding the
embodiments which are described below.
[0035] Completing the description of the system 10, with reference
to the '408 patent as an instructive example, heated, pressurized
air is conducted into the convective device 24 which conveys the
air from the inlet port 22 into its interior, imposing a heat loss
that reduces the temperature level of the air, and extravises the
heated, pressurized air through one or more surfaces of the
convective device 24. The system 10 thus delivers
thermally-regulated air to the convective device 24, and the device
distributes the thermally-regulated air around a person or a
specific body area of the person.
[0036] In order to afford protection from injury that could result
should the end 20 become separated from the inlet port 22, either
by accident or by intentional action, an interface device that
controls the interface between the inlet port 22 and the end 20 is
provided. The interface device acts to wholly or partly close the
end 20 of the air hose 16 in order to reduce, restrict, attenuate,
or even stop the flow of air through the end 20. When the end 20 is
connected, coupled, or joined to the inlet port 22, the interface
device operates to allow pressurized, thermally-regulated air to
flow easily through the end 20 into the convective device 24.
Following connection, when the end 20 is disconnected, uncoupled,
or separated from the inlet port 22, the interface device operates
to wholly or partly close the end 20 in order to reduce, restrict,
attenuate, or even stop the flow of air through the end 20. Refer
now to the remaining drawings, which illustrate various embodiments
of the interface device.
Embodiment of FIGS. 2A-2E
[0037] In FIGS. 2A-2E an interface device that exemplifies this
invention is illustrated. The interface device 200 includes two
frusto-conical sections 210 and 212 made of any material that can
be joined to an end of an air hose and received in and supported by
an inlet port such as the inlet port 22. In this regard, taking the
air hose 16 as an example, its end 20 may include an annulus 20a
made of a material that is easily joined to the material of which
the sections 210 and 212 are made. Representative materials for the
elements 210, 212, and 20a may include, for example, durable
plastics, composites, or any equivalent materials or combinations
thereof. The frusto-conical section 210 has a wall 220 through
which at least one opening is provided. For example, two opposing
openings 221 and 222 are shown in these figures. The opposing
openings 221, 222 are elongate, semi-rectangular fenestrations
which open through the wall 220. In this example, each of the
openings 221, 222 has a major dimension I which extends lengthwise
on the section 210. A single opening 225, also an elongate
semi-rectangular fenestration, opens through the wall 220. This
opening 225 has a major dimension I which extends crosswise on the
section 210. The narrow end 228 of the section 210 has a structural
member 229 that extends entirely across it. The member 229 is
illustrated as having the shape of an hour glass with rounded ends,
although this is not necessary to the practice of the invention.
The wide end 230 of the frusto-conical section 210 is open. The
frusto conical section 212 acts on or against the frusto-conical
section 210 in order to provide relative rotation therewith. In the
example shown in these figures, this is accomplished by disposing
the section 212 on the inside of the section 210 with its narrow
end 248 brought near to or against the inside surface of the narrow
end 228 of the section 210 and fixing, joining, or attaching the
section 210 to the annulus 20a near the wide end 230 of the section
210. This allows the section 212 to rotate about its axis, at the
end 20, within the frusto-conical section 210. In this arrangement,
the section 212 has a wall 240 through which at least one opening
is provided. For example, two opposing openings 241 and 242 are
shown in these figures. The opposing openings 241, 242 are
elongate, semi-rectangular fenestrations which open through the
wall 240. In this example, each of the openings 241, 242 has a
major dimension I which extends lengthwise on the section 212. The
narrow end 248 of the section 212 has a structural member 249 that
extends entirely across it. The member 249 is illustrated as having
the same shape as the member 229, although this is not necessary to
the practice of the invention. The wide end 250 of the
frusto-conical section 212 is open. Each of the sections 210 and
212 is provided with a semi-cylindrical trunnion, with the trunnion
252 being mounted on and projecting outwardly from the wall 220 at
the end 229a of the opening 220, and the trunnion 254 being mounted
on and projecting outwardly from the wall 240.
[0038] As shown in the figures, especially FIGS. 2A and 2D, the
section 212 is received in the section 210, and the wide end 230 of
the section 210 is received in and joined to the annulus 20a. The
joinder of these elements may be by any appropriate means that
substantially or entirely seals the joint between the annulus 20a
and the section 210. The joint may be permanent or reducible; it
may be immobile or permit rotation between the interface device 200
and the annulus 20a. When the section 212 is received in the
section 210, the trunnion 254 extends through the opening 225 in
the section 210, constraining the rotation of the section 212
within the section 210 to an arc whose length extends from the end
229a to the end 229b of the opening 225. In these figures, the arc
is approximately 90.degree.. When the section 212 is rotated in the
direction of arrow 284 toward the end 229a, rotation is stopped at
a position of the section 212 where its opposing openings 241, 242
are respectively aligned with the opposing openings 221, 222 of the
section 210. At this position, seen best in FIG. 2D, the alignment
of the opposing openings provides at least one aperture through the
interface device 200 that is in communication with the end 20 and
permits air to flow through the air hose 16, to and through the end
20, through the interface device 200, at a relatively high rate. In
this figure (and in FIGS. 2C and 2E), air flow is indicated by
arrows 283. For example, the rate may be in an operational range
from 24 CFM (cubic feet per minute) to 40 CFM. Next, when the
section 212 is rotated toward the end 229b, rotation is stopped at
a position of the section 212 where its opposing openings 241, 242
are respectively blocked, closed, or shut by the unapertured
portion of the wall 220. Similarly, at this position of the section
212, the opposing openings 221, 222 of the section 210 are
respectively blocked, closed, or shut by the unapertured portion of
the wall 240. At this position, the blocking of the openings
221,222,241, and 242, and closure of at least the narrow end 228 of
the section 210 reduces, attenuates, restricts or blocks air
flowing through the end 20 and the interface device 200. The effect
produced thereby can range from wholly cutting off the airflow
through the end 20 and the interface device 200 to restricting the
airflow therethrough to some rate that is lower than the lower end
of the operational range.
[0039] As thus far described, the interface device 200 can be
operated manually. Self-actuated operation of the interface device
200 can be understood with reference to FIGS. 2 A and 2B. In these
figures a spring 270 has a coil 271 and two ends 272 and 274. The
end 272 is disposed at one end of the spring coil 271, crosswise to
the axis of the coil. The end 274 projects from the other end of
the spring coil 271 generally parallel to the axis of the coil. A
flange 276 projecting into the frusto-conical section 210 from the
structural member 229 has a slot 277 that receives the end 272 of
the spring 270. A thick annulus 278 is mounted on the rear surface
of the structural member 249 of the frusto-conical section 212. A
recess 279 is centered in the structural member 249 and the thick
annulus 278, and a hole 280 is provided through the member 249 and
the annulus 278. The spring 270 is seated in the recess 279 and the
end 274 of the spring 270 extends through the hole 280 when the
section 212 is received within the section 210. When seated, the
spring 270 acts between the frusto-conical sections 210 and 212 by
urging the section 212 to rotate in the direction of the arrow 282
until the trunnion 254 engages the end 229b of the opening 225.
This stops the frusto-conical section 212 at the position where the
flow of air is reduced, attenuated, restricted or blocked. Manual
engagement of the trunnion 254 with a force directed in the
direction of the arrow 284 moves the trunnion to the end 229a where
it abuts the trunnion 252 and rotates the frusto-conical section
212 to the position where the alignment of the opposing openings
provides at least one aperture through the interface device 200
that is in communication with the end 20 and permits air to flow
from the end 20, through the interface device 200, at the
relatively high rate.
[0040] The operation of the interface device with respect to the
interface between the end 20 of the air hose 16 and the inlet port
can be understood with reference to FIGS. 2C-2E. Assuming for
illustration that the inlet port 22 includes an inlet port
structure such as that disclosed in U.S. Pat. No. 6,309,408, it
would include a sheet 290 of flexible, somewhat deformable material
(such as cardboard) in which a port opening 291 is provided. The
sheet 290 may also include a tab 292 with an opening 294. The
interface device 200 is mounted to the end 20 of the air hose 16 as
described above, and the interface device 200 is mated with the
port opening 291, with the narrow ends 228 and 248 oriented toward
and extending through the port opening 291. Either before or after
the narrow end of the interface device 200 is placed in the port
opening 291, the frusto-conical section 212 is rotated in the
direction of the arrow 284 until the trunnion 254 is brought
against the trunnion 252. This places the section 212 into the
position where the alignment of the opposing openings provides at
least one aperture through the interface device 200 that is in
communication with the end 20 and permits air to flow from the end
20, through the interface device 200, at the relatively high rate.
The frusto-conical section 212 can be retained in this position in
resistance to the urging of the spring 270 by means of the opening
294 which is brought over the trunnions 252 and 254 by bending the
tab 292 toward the interface device 200. Now, if the air hose 16 is
disconnected from the inlet port, the tab 292 is bent away from the
trunnions 252 and 254, and the spring 270 will urge the
frusto-conical section in the direction of the arrow 282 to the
position at which the flow of air out of the end 20 is reduced,
attenuated, restricted or blocked.
Embodiment of FIGS. 3A-3E
[0041] Refer now to FIGS. 3A-3E for an understanding of another
embodiment of the interface device. In these figures, the interface
device embodiment includes a shutter. In this embodiment, when the
end 20 and the inlet port 22 are brought together the shutter opens
(or, is opened) to permit pressurized air to flow out of the end 20
into the convective device. Likewise, when the end 20 is separated
from the inlet port 22 the shutter closes (or, is closed), to
reduce, restrict, or prevent the flow of air out of the end 20,
thereby preventing burn accidents or improper operation of the
equipment.
[0042] The interface device 300 includes an end piece 305
comprising a tubular section 307 and a front piece 309 in the form
of a concaved rectangular frame. The front piece 309, disposed on
one end of the tubular section 307, has a concaved rectangular
surface 311 around the periphery of which a frame with side slots
(one indicated by 313) is disposed. A generally triangular opening
315 is disposed generally in the center of the surface 311 and
there is a rounded half cylindrical slot 317 disposed on one edge
of the opening 315 generally on the longitudinal axis of the
surface 311. The end piece 305 is preferably a unitary element
formed, possibly, by molding a durable plastic. The end piece 305
is assembled to an annular collar 320 on the end 20, for example by
threaded screws that extend through the second end of the tubular
section 307, although other joinings are possible. When assembled
in this manner, the opening 315 permits pressurized air to flow out
of the end 20.
[0043] The interface device 300 further includes a flexible shutter
325 having a generally rectangular shape that corresponds to the
rectangular shape of the surface 311. The flexibility of the
shutter 325 permits it to assume the concaved shape of the surface
311 when the shutter is received in the frame of the front piece
309 with its sides 326 received in the side slots 313.
Alternatively, the shutter 325 could be formed of a hard plastic
conformed to fit the shape of the surface 311. The shutter 325 is
shorter than the surface 311, enabling it to slide thereon. The
shutter includes, in one end portion, one or more triangular
openings 327. When the shutter is slid away from the opening 315 in
the surface 311 to a position against the edge 318 of the end
piece, the unbroken portion of its other end portion blocks the
opening 315, thereby preventing or restricting the flow of
pressurized air out of the end 20. When the shutter 325 is slid
toward the opening 315 to a position against the edge 319, the one
or more openings 327 align with the opening 315 and permit
pressurized air to flow out of the end 20.
[0044] The operation of the shutter 325 may be manual or it may be
automated by provision of a spring 330. The spring 330 acts between
the shutter 325 and the end piece 305, being relatively more
compressed when the shutter 325 is slid toward the edge 319, and
urging the shutter from that position toward the edge 318. The
spring 330 is retained to act in this manner by a gudgeon 328 that
projects off one side of the shutter 325 into one end of the
spring, in the direction of the cylindrical slot 317, which
receives the other end of the spring 330. A retainer 331 extends
away from the other side of the shutter 325 and broadens into a tab
333. The shutter 325 is retained against the surface 311, in the
frame of the front piece 309 by a concaved rectangular cover 340
having a center opening 341 aligned with the opening 315. An
elongate slot 343 opens into the periphery of the center opening
341, and an arcuate lip 342 is provided adjacent the periphery of
the center opening 291, diametrically opposite the slot 343. The
retainer 331 projects through the slot 343 and traverses the slot
from end to end as the shutter 325 is moved between the positions
described above. When the shutter 325 is slid to the position at
which it is stopped against the edge 319, the openings 315, 327,
and 341 align, permitting pressurized air to flow out of the end
20. At this position, the retainer 331 is retained against the
arcuate lip 345.
[0045] A self-actuating operation of the interface device 300 is
best seen in FIGS. 3D and 3E. To bring the end 20 together with the
inlet port 22, the shutter 325 is slid toward the edge 319 by
pressure applied against the tab 333. With the shutter 325 held in
this position, the end piece 305 is brought against the sheet 290
of the inlet port 22, with the tab 333 extending through the port
opening 291. The compressed spring 330 urges the retainer 331 into
engagement against the periphery of the port opening 291. This
keeps the shutter in the position at which pressurized air flows
out of the end 20, through the inlet port 22. The end 20 is
separated from the inlet port 22 by sliding the end piece against
the sheet 290 in the direction of the arrow 370. This disengages
the tab 333 and allows the shutter to be returned by the spring 330
to the position against the 318 where the opening 309 is blocked,
covered, or closed by the unaperatured portion of the shutter
325.
Embodiment of FIGS. 4A and 4B
[0046] Refer now to FIGS. 4A and 4B for an understanding of another
embodiment of the interface device. In these figures, the interface
device embodiment 400 includes a sleeve 418 of flexible material
having an open end 422 that transitions to a shallow bowl-like
collar and an end 424 that has a normally closed configuration in
which opposing sections of the sleeve 418 at the end 424 abut
without being permanently joined. The sleeve 418 is made of a
durable flexible plastic such as polypropylene or polyethylene and
has a remembered shape that maintains the end 424 in its normally
closed configuration. Opposing longitudinal living hinges 415 and
417 connect two opposing segments 419 and 420 of the sleeve 418.
Forces applied in opposition to the living hinges 415 and 417 near
the end 424 (indicated by arrows 435) cause the end 424 to open and
the sleeve 418 to assume an open tubular configuration. When the
opposing forces 435 are released, the sleeve 418 returns to its
remembered shape in which the end 424 is in its normally closed
configuration.
[0047] The interface device 400 is operated by applying opposing
forces to each side of the sleeve 418, on the living hinges 415 and
417, near the end 424 as indicated by the arrows 435 in FIG. 4B.
This opens the end 424 into a roughly cylindrical shape that is
received in the port opening 291. The end 424 is inserted into the
port opening 291, and the opposing forces are released. This causes
the sleeve to seek its remembered shape, and engage the rim of the
port opening 291, thereby retaining the now-open end 424 within the
port opening 291, permitting air to flow from the end 20, through
the interface device 400, at the relatively high rate. To withdraw
the interface device 400 from an inlet port, opposing forces are
again applied to the sleeve 418 to flex the sides of the sleeve 418
at the living hinges 415, 417 in the directions indicated by the
arrows 435, thereby disengaging the sleeve 418 from the port
opening 291 and allowing the end 424 to be withdrawn from the port
opening 291. When the end 424 is withdrawn from the inlet port and
the opposing forces 435 are released, the sleeve 418 returns to its
remembered shape, thereby returning the end 424 to its
normally-closed configuration, in which the flow of air out of the
end 20 is reduced, attenuated, restricted or blocked.
Embodiment of FIGS. 5A-5C
[0048] Refer now to FIGS. 5A-5C for an understanding of another
embodiment of the interface device. In these figures, the interface
device embodiment 500 includes a spring structure with a base ring
510 having an opening 511. An imaginary axis A, centered in and
perpendicular to the base ring 510, may be defined. A pair of
elongate flexible tines 512 and 514 are mounted in opposition on
one surface of the base ring 510, extending along and beside the
axis A. The other surface of the base ring 510 has the same shape
and dimensions as the annulus 20a. The flexible tines 512 have the
shapes of shallow descending arcs that open in opposite directions
away from the axis A. The flexible tines 512 and 514 are formed
from any appropriate flexible material that retains a memory of its
original shape when flexed by an applied force and that returns to
the remembered shape when the force is removed. One such material
is a sturdy, durable plastic such as polypropylene or polyethylene.
The flexible tines 512 and 514 have wedge-shaped tips with vertices
513 and 515, respectively, that extend outwardly from the tines. A
sleeve 518 of durable flexible material such as polypropylene or
polyethylene is molded into a shape having opposing ends 522 and
524, wherein the end 522 transitions to a shallow bowl-like collar
and the end 524 has a normally closed configuration in which
opposing sections of the sleeve at the end 524 abut without being
permanently joined. Force applied in opposition to the sides of the
end 524 cause the end 524 to open. Opposing apertures 519 and 520
are provided through the sleeve 518 near the end 524. The interface
device 500 is assembled by attaching, joining, or bonding the base
ring 510 concentrically to the annulus 20a and then sliding the
sleeve 518, end 522 first, over the tines 512 and 514, until the
end 522 is brought against the base ring 510. When the end 522 is
seated against the base ring 510, the vertices 513 and 515 are
received in and protrude through the apertures 520 and 519. The end
522 is attached, joined, or bonded to the base ring 510. When
assembled, the interface device is maintained in a normally closed
configuration by the tines 512 and 514 which seek their remembered
shapes, exerting drooping outwardly-directed opposing forces on the
end 524, which maintains the end 524 in its normally-closed
configuration. As best seen in FIGS. 5B and 5C, the drooping
component of the curvature of tines 512 and 514 imposes a
pronounced hook on the portion of the sleeve 518 that includes the
end 524. The interface device 500 is operated by applying opposing
forces to each side of the sleeve 518, near the end 524 just behind
the vertices 513 and 515, as indicated by the arrows 535 in FIG.
5B. This opens the end 524 into a roughly cylindrical shape that is
received in the port opening 291. The end 524 is inserted far
enough into the port opening 291 to place the vertices 513 and 514
through the port opening 291 where they engage the back surface of
the sheet 290. When the opposing forces are removed, the tines 512
and 514 seek their remembered shapes and retain the now-open end
524 within the port opening 291, permitting air to flow from the
end 20, through the interface device 500, at the relatively high
rate. To withdraw the interface device 500 from an inlet port,
opposing forces are again applied to the sleeve 518 to flex the
sides of the sleeve 518 and the tines 512 and 514 in the directions
indicated by the arrows 535, thereby disengaging the vertices 513
and 514 from the sheet 290. When the end 524 is withdrawn from the
inlet port and the opposing forces 535 are released, the tines 512
and 514 seek their remembered shapes, thereby returning the end 524
to its normally-closed configuration, in which the flow of air out
of the end 20 is reduced, attenuated, restricted or blocked.
Embodiment of FIGS. 6A and 6B
[0049] Refer now to FIGS. 6A and 6B for an understanding of another
embodiment of the interface device. In these figures, the interface
device embodiment 600 includes a single frusto-conical section 610
made of a durable flexible material such as plastic and having a
narrow end 628 and a wide end 630. Both of the ends 628 and 630 are
open, and the wide end 630 transitions to a shallow bowl-like
collar. At the narrow end 628 there are four elongate slots 612
that extend from the end 628 longitudinally along the section 610
for about a third of the length of the section 610. The slots are
arrayed at 90.degree. around the narrow end 628 of the section 610
and define four corresponding legs 614 extending from the narrow
end 628. The legs 614 are flexible and can be flexed inwardly
toward one another. A ball or sphere 620 of light durable material
such as plastic is disposed on the inside of the section 610,
wherein it is free to move between the narrow end 628 and the wide
end 630. The ball 620 has a diameter that fills the narrow end 628.
The ball 620 may be hollow and have apertures therein to allow a
limited amount of air to pass through the ball itself. Although not
shown in these drawings, the ball 620 may be tethered to the inside
of the section 610, or constrained therein by a cross piece at the
wide end 630. The interface device 600 is assembled by receiving
the annulus 20a in the shallow bowl-like collar at the wide end 630
where it is attached, joined, or bonded to the collar.
[0050] The interface device 600 is operated by squeezing together
the legs 614. The narrow end 628 is inserted into the port opening
291, which, for this embodiment may have a quatrefoil pattern for
receiving the legs 614. When the squeezing force is removed from
the legs, they spring back toward their unflexed positions and
frictionally engage the port opening 291. Alternatively, the
engagement of the port opening 291 may be effected by relying on
the taper of the legs 614. In this case as the interface device 600
engages sheet 290, the wide end of the tapered leg 614 results in a
friction fit with the opening 291 The quatrefoil pattern of the
port opening prevents ball 620 from entering the narrow end 628,
permitting air to flow from the end 20, through the interface
device 600, at the relatively high rate. To withdraw the interface
device 600 from an inlet port, the legs 614 are again squeezed
together until they are disengaged from the port opening 291. When
the narrow end 628 is withdrawn from the inlet port and the
squeezing force is released, the legs 614 seek their remembered
positions, and the ball 620 is now free to enter the narrow end
620, where it is impelled by the pressurized air flowing through
the end 20. Here, the ball 620 in reduces, attenuates, restricts or
blocks the flow of air out of the end 20.
Embodiments of FIGS. 7A/7B, 8A-8B, and 9A/9B
[0051] FIGS. 7A, 7B, 8A-8C, 9A and 9B contain subject matter
originally disclosed in FIGS. 14A, 14B, 15A-15C, 16A, and 16B,
respectively, of U.S. patent application Ser. No. 09/546,078 from
which this application is continued, in part. In these figures
another embodiment of the interface device relies on the opening
and closing of a valve to control the flow of air out of the end
20. In this embodiment, bringing the end 20 and the inlet port 22
together causes the valve to open and permits pressurized air to
flow out of the end 20 into the convective device. Likewise,
separating the end 20 from the inlet port 22 causes the valve to
close, reducing, restricting, or preventing the flow of air out of
the end 20, thereby preventing burn accidents or improper operation
of the equipment.
[0052] FIG. 7A depicts an inlet port 22, the end 20, and a nozzle
700 (shown partially received in the end 20 for illustration only).
The nozzle 700, received in the end 20 of the air hose 16, includes
a valve 730. As seen in FIG. 7B, as the nozzle 700 is received in
the inlet port 22, the valve 730 including a flap 734 cooperates
with the inlet port 22 to enable airflow out of the end 20 through
the inlet port 22. Also, while FIG. 7B depicts the valve flap 734
opening toward the inlet port 22 upon activation, it is also
possible to design a valve system in which the flap 734 opens
towards the air hose 16 upon activation.
[0053] The nozzle 700, preferably made of a durable material such
as a hard plastic or equivalent, has an arch-shaped forward section
706, that transitions to a shoulder 708. The shoulder 708
transitions to a rear arched-shaped section 709. The rear section
709 is enabled to fit snugly to the end 20 of the air hose 16, by
means of an adapter 20b. The nozzle 700 is assembled, attached, or
brought together with the air hose 16 by inserting the nozzle 700,
rear section 709 first, into the adapter 20b so far as to bring the
shoulder 708 against the adapter 20b. There, the shoulder 708 may
be bonded to one side of the adapter 20b, the other side of which
is bonded to the end 20 of the air hose 16.
[0054] The end 20 and the inlet port 22 are brought together by
inserting the arched-shaped section 706 into the port opening 291a
(which has an arched shape that corresponds to that of the section
706) open end first, and sliding the section 706 into the opening
291 until the engagement between the valve 730 and the opening 291
cause the valve to open, as is explained below.
[0055] The flap 734 has an arched shape with a dimension 736
substantially the same as the corresponding inner dimension of the
arch-shaped section 709. It should be noted that the flap 734 need
not perfectly seal the end 20 to be effective. The flap 734 stops,
blocks, or restricts the flow of air, or substantially stops,
blocks or restricts the flow of air, when the end 20 is not
received in the inlet port 22.
[0056] As depicted in FIGS. 7A and 7B, in addition to the flap 734,
the valve 730 includes a hinge lever 738 which is rigidly attached
to the flap 734. At the intersection of the hinge lever 738 and
flap 734 is an axle or pin (not shown) about which the flap 734 and
hinge lever 738 pivot. The hinge lever 738 cooperates with the
inlet port 22, being moved from a position perpendicular to the air
hose 16, to a position against the air hose 16, to permit the end
20 to be brought together with the inlet port 22. The engagement of
the hinge lever 738 with the lower edge 291b of the opening 291a
rotates the flap 734 from a position blocking the flow of air
(shown in FIG. 7A) to a position (open position) in which air may
flow when the end 20 is brought together with the inlet port 22.
Not specifically shown is the mechanism which returns the flap 734
from the open position to the blocking position (FIG. 7A) when the
end 20 is disengaged from the inlet port 22. The return-mechanism
can be a spring or some such torsioning member (not shown) which is
put under load by the action of the flap 734 being forced into the
open position (FIG. 7B). Additionally, in some orientations, the
flap 734 can be returned to its seated position by the frictional
force of the airflow within the air hose 16. Once the valve flap
734 is seated, it will be held in place by the static pressure
developed by the blower.
[0057] Optionally, a pair of magnets 739a and 739b may be used to
keep the flap 734 in the blocking position when the end 20 is
separated from the inlet port 22. The first magnet 739a, is
disposed in the rear section 709 and the second magnet 739b is
disposed the flap 734. The first magnet 739a cooperates with the
second magnet 739b so that the flap 734 blocks the flow of air when
the end 20 is separated from the inlet port 22. Although not
specifically shown, magnets can also be used with the flap 734 of
the actuator mechanisms shown in FIG. 8A, described below. In
another aspect of this embodiment, not shown, the flap 734 may be
opened in the direction of the air hose 16 instead of the inlet
port 22, so that the flow of air through hose 16 acts to close the
flap 734 when it is not engaged.
[0058] FIGS. 8A through 8C depict a valve 830 with a circular valve
flap 834, coupled to a cam actuation mechanism, and disposed in a
single, substantially tubular section 806. The tubular section 806
is attached, at one end to the end 20 of the air hose 16. The flap
834 has a diameter substantially equal to the diameter of the
tubular section 806. As shown in FIG. 8A, the flap 834 includes a
pair of cams 840a and 840b rigidly attached to the flap 834, 180
degrees apart. Alternately, the cam can be attached to an axle
running through the diameter of the flap 834, with the axle being
rigidly attached to the flap, so that the face of the flap and the
cam facets remain in a fixed relationship. The cam actuation
mechanism includes rounded surfaces which permit the cams
840a/840b, and attached flap 834, to rotate as the cam engages the
surface surrounding the inlet port 22. The rotation of the cams
840a/840b is shown if FIG. 8B. As shown in FIG. 8C, the flat facet
surfaces of the cams 840a/840b permit those surfaces to fixedly
seat against the inlet port 22 as the end 20 and the inlet port 22
are brought together. With the cams 840a/840b seated, the flap 834
is locked in an open position to permit the flow of air. Not shown
is a return mechanism which forces the flap 834 into the blocking
position (FIG. 8A). As above, the return mechanism can be a spring,
or equivalent that is put under load as the flap 834 is forced into
the open (non-blocking) position.
[0059] FIGS. 9A and 9B depict a gear rack valve actuator mechanism
for a valve 930 having a circular valve flap 934. The mechanism
includes a lever 950 which engages the inlet port 22 to open the
flap 934. The lever 950 is connected to a first gear 952, the teeth
of which are intermeshed with the teeth of a second gear 954. In
turn, the second gear 954 is attached to the flap 934. As the lever
950 is engaged, it is forced into the body of the hose 16. The
action of the lever 950 and the gears 952/954 open the flap 934 so
that pressurized air can pass out of the end 20 into inlet port 22.
Optionally the a pair of magnets 739a/739b are used to keep the
flap 934 in the blocking position when the end 20 is separated from
the inlet port 22. Alternatively, the opening of the flap 934 into
the direction of the airflow acts to force the flap 934 into a
blocking position when lever 950 is not engaged by the inlet port
22.
* * * * *