U.S. patent application number 13/206489 was filed with the patent office on 2011-12-01 for valve system for prosthetics.
This patent application is currently assigned to COYOTE DESIGN & MANUFACTURING, INC. Invention is credited to DALE PERKINS, MATT PERKINS.
Application Number | 20110295386 13/206489 |
Document ID | / |
Family ID | 40932458 |
Filed Date | 2011-12-01 |
United States Patent
Application |
20110295386 |
Kind Code |
A1 |
PERKINS; MATT ; et
al. |
December 1, 2011 |
VALVE SYSTEM FOR PROSTHETICS
Abstract
A valve system regulates the air pressure in the space(s)
between a residual limb, or liner-covered limb, and a hard socket
of an external prosthesis, for example, for improving donning and
doffing the prosthesis, and/or during walking and other normal use
of the prosthesis. The valve system may include a
manually-controlled air outlet and inlet valve that may be
installed on a distal region of a hard socket, and/or an automatic
one-way outlet valve. The manually-controlled valve is preferably
opened and closed by twisting of a handle portion of the valve
system, wherein partial rotation of the handle portion relative to
the base portion of the valve system creates slight separation of
the handle and base portions to form a gap through which may pass
air from the well of the socket. This simple twisting, or partial
rotation, provides a valve that stays open hands-free, so that the
wearer may open the valve and then use his/her hands to don or doff
the prosthesis. The manual valve may include a system for
preventing the handle and base from becoming entirely separated
during normal use, which preferably is a snap-fit of the base onto
the handle that retains the ability of the handle and base to
rotate relative to each other, and a stop(s) that limit(s) the
amount of relative rotation of the handle and base portions of the
valve. Opening and closing of the manual valve may be accomplished
by a ramp system, so that, upon rotation of the handle in one
direction, the handle comes close to, and seals with, the base, and
upon rotation of the handle in the opposite direction, the handle
becomes slightly distanced from, and unsealed from, the base.
Inventors: |
PERKINS; MATT; (BOISE,
ID) ; PERKINS; DALE; (BOISE, ID) |
Assignee: |
COYOTE DESIGN & MANUFACTURING,
INC
BOISE
ID
|
Family ID: |
40932458 |
Appl. No.: |
13/206489 |
Filed: |
August 9, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12364511 |
Feb 2, 2009 |
7993413 |
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13206489 |
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11527752 |
Sep 25, 2006 |
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12364511 |
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61024913 |
Jan 31, 2008 |
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60719785 |
Sep 24, 2005 |
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Current U.S.
Class: |
623/34 |
Current CPC
Class: |
A61F 2002/805 20130101;
A61F 2/80 20130101 |
Class at
Publication: |
623/34 |
International
Class: |
A61F 2/80 20060101
A61F002/80 |
Claims
1. A pressure-control system for a prosthetic hard socket, the
pressure-control system comprising: a prosthetic hard socket
comprising a wall having an outer surface and an interior surface
defining a well for receiving a residual limb, and said wall having
a hole extending from said outer surface to said interior surface;
and an air valve comprising: a base on said outer surface of the
hard socket over said hole in the wall; a handle connected to said
base and manually rotatable relative to the base; and an air
passageway through said base and said handle that is blocked when
the handle is rotated relative to the base to a closed position,
and that is unblocked for air flow through the valve and the hole
into and out of the hard socket, when the handle is rotated
relative to the base to an open position; and wherein the air valve
comprises at least one stop adapted to limit rotation of said
handle relative to the base to a portion of a full rotation, the
portion being in the range of 30-90 degrees, so that the handle
rotates only said portion of a full rotation when moving from the
closed to the open position.
2. A pressure control system as in claim 1, wherein, when the
handle is rotated said portion of a full rotation to the open
position, the handle is distanced from the base to form a radial
gap between said base and said handle.
3. A pressure control system as in claim 2, wherein the handle is
distanced from the base by rotating into said open position by
means of ramps provided on the handle sliding on cooperating ramps
provided on the base.
4. A pressure control system as in claim 3, wherein said ramps
provided on the base are slanted so that the handle rotating said
portion of a full rotation moves the handle axially out from the
base to form said radial gap.
Description
[0001] This application is a continuation of Non-Provisional
application Ser. No. 12/364,511, filed Feb. 2, 2009 and issuing on
Aug. 9, 2011 as U.S. Pat. No. 7,993,413, which claims benefit of
Provisional Application Ser. No. 61/024,913, filed Jan. 31, 2008
and which is a continuation-in-part of Non-Provisional application
Ser. No. 11/527,752, filed Sep. 24, 2006, now abandoned, which
claims benefit of Provisional Application Ser. No. 60/719,785,
filed Sep. 24, 2005, the entire disclosures of which are
incorporated herein by this reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to prosthetics, and more
specifically to a valve system for air release from an external
prosthetic such as may be used on a residual limb.
[0004] 2. Related Art
[0005] Gravitational and other forces tend to cause separation
between a prosthetic limb and a residual limb. This happens, for
example, during the swing phase of the gait, when a prosthetic leg
is additionally subjected to centrifugal forces. The manner in
which an artificial limb is suspended and/or attached to the
residual limb determines the amount of control an amputee has over
the prosthesis. Patients have routinely worn a variety of belts,
straps, cuffs and harnesses to prevent the prosthetic limb from
separating from the residual limb, but such devices are
inconvenient and tend to cause chafing against the patient's body,
giving rise to sores and abrasions.
[0006] It has long been appreciated that differential air pressure,
often referred by those of skill in the art as "suction," may be
utilized to retain or suspend, or assist in retaining or
suspending, a prosthetic limb on a patient's residual limb.
"Suction suspension" typically involves a hard socket and a
cooperating liner positioned between the residual limb and the
prosthetic socket. The liner is rolled onto the residual limb for a
suction, slight compression, and/or gripping connection of the
inner gel layer (or otherwise tacky layer) of the liner to the skin
of the residual limb. The liner-covered limb is then inserted into
the prosthetic socket, and the outer surface/layer of the liner
preferably forms a suction, grip, or other interference fit to the
socket to interfere with the socket falling off the limb.
[0007] Said "suction" fit between the liner and the socket, due to
the material and texture of today's preferred liner as further
discussed below, may more accurately be referred to as a
"partial-suction" fit. In such a "partial-suction" fit, the outer
surface of the liner and its close fit with the interior surface of
the socket will provide significant resistance to air entering the
socket from outside the socket (via the top opening of the socket).
Still, because today's preferred liners do not form a true
air-tight seal with the socket, some air will slowly enter the
socket, especially during the swing portion of the wearer's gait
and during periods of relative inactivity.
[0008] Socket liners frequently have been called "suction liners,"
"gel liners," "roll-on liners" or "suspension liners" and include
the "first generation" of gel-layer-only liners, and also the
modern "second generation" liners currently preferred by most
wearers of prosthetics. These modern liners "second generation"
liners typically comprise a thin textile/fabric outer layer that is
fixed to the gel-like inside layer. Thus, the second generation of
liners is similar to the first generation in its connection to the
residual limb, but its connection to, or cooperation with, the
socket is Modified by the presence of the textile/fabric layer. The
term "suction liner" began with the first generation liners, which
featured the gel layer contacting both the residual limb (liner's
inner surface) and the socket (liner's outer surface), and which,
therefore, could be used to create a fairly high amount of pressure
differential between the inside of the socket (in the "well" of the
socket) and the surrounding ambient air. The terms "suction liner"
and "suction socket" are still used by many manufacturers,
prosthetic technicians, insurance and medicare/medicaid entities,
and wearers of prosthetics, even though the modern liners, with
their textile/fabric outer layers, typically do not form what would
be called "true" or "pure" suction with the socket, as further
discussed below. See the discussion of suction liners in Janusson,
et al. (U.S. Pat. No. 6,706,364) and Janusson, et al. (U.S. Pat.
No. 6,626,952).
[0009] Preferred socket liners are usually fabricated from
silicone, urethane, or other gel-like material that grips the limb
to such an extent that they need to be rolled-onto the limb from a
rolled-up "doughnut" form, rather than pulled on like a sock. When
rolled-on, there is little, if any, air remaining between the inner
surface of the roll-on liner and the limb, and the roll-on liner is
snug against the limb all the way around the circumference of the
limb. Also, the inner surface of the roll-on liner is of such
material and tacky texture that air will not be able to, or be very
unlikely to, enter between the roll-on liner and limb. Thus, the
roll-on liner may be said to form a suction fit and/or a slight
compression fit with the limb. A distal force on the liner, such as
caused by the swing of a gait with a prosthetic leg, may tug on the
roll-on liner but typically does not loosen, lower, or remove the
liner from the limb.
[0010] The hard socket is usually laminated or otherwise fabricated
from polyethylene, polypropylene, or other copolymers, for example,
and is donned over the liner and the residual limb. A suction-fit,
including a partial-suction fit, as discussed above, may form
between the liner-sheathed limb and the interior of the socket. A
"true" suction fit (allowing high suction, greater amount of
vacuum) will be more likely to form if the liner exterior surface
is smooth and flexible enough to conform to the contours of the
residual limb, for example, non-air-permeable material such as the
silicone, urethane, or other rubbery or gel-like material such as
described above for the liner-to-limb connection; if the interior
surface of the socket is also smooth and non-air-permeable; and, of
course, if the socket has no un-sealed holes or apertures.
[0011] A "partial" suction fit (allowing lower suction, low amount
of vacuum) is more likely to form if one of these conditions is not
met, for example, if the outside of the liner is the thin fabric or
other woven material bonded to a rubbery/gel-like interior layer of
the liner, for example, as described above for "second generation"
liners. In such a case, some air will tend to leak through or past
the fabric layer of the modern liners into the well of the socket,
that is, between the liner and the socket interior surface, so that
there is typically not a true air-tight seal between the two.
However, the air leaks fairly slowly because of the preferred close
fit between the contour of the liner-cover limb and the contour of
the internal surface of the socket. This slow air leakage and close
fit typically allow their to be a "partial" suction fit between the
socket and the liner outer surface, and this "partial" suction fit
tends to be more comfortable for many wearers that a "true" or
"full" suction fit. In other words, a textile/fabric-covered liner
and the resulting "partial" suction tends to be more comfortable
than the stronger "tugging" on the residual limb created by the
"full" suction of first generation, gel-layer-only liner. The air
that slowly leaks into space(s) in between the socket and the liner
tends to be expelled with each step due to the force of the
residual limb pushing into the socket. This way, modern,
fabric-covered roll-on liners still tend to create some pressure
differential between the well of the socket and the ambient
air.
[0012] Therefore, many of skill in the field of prosthetics still
apply the term "suction" to a fit or suspension of the prosthetic
to the limb ranging from excellent suction (with a "true" seal,
large resistance to equalization of pressure between the inside and
the outside of the socket) to slight suction (with a "partial"
seal, small resistance to said equalization such as in many popular
liners). Therefore, the terms "suction," "suction-fit," and
"suction suspension" herein are therefore not limiting to a
particular amount of pressure differential, but to the general
process known well in this field of providing a "roll-on" liner or
other "interference" liner that helps keep a socket on a residual
limb while creating at least a small amount of blockage/hindrance
to air freely moving in and out of the socket well past the
residual limb.
[0013] Therefore, it may be said that any region or amount of
negative pressure in the space(s) between the liner-sheathed stump
and the interior of the socket, relative to ambient (outside of the
socket), may help to hold the prosthesis upon the limb during use.
Certainly, more suction is more secure than slight suction, but
there may be comfort sacrifices that result from more suction, for
example, chaffing or pulling on the limb. A high-suction prosthesis
suspension system may cause the user a discomforting disturbance of
circulation in the limb on which the prosthesis is worn, due to the
build up of a high degree of partial vacuum during walking,
particularly in warm humid weather. Therefore, a very popular
conventional roll-on liner is one such as the Ohio Willow Wood
Alpha.TM. liner, which has multiple layers, that is, a
rubbery/gel-like inner layer and a thin fabric outer layer bonded
to the inner layer, so as to moderate the suction to a reasonably
effective amount without allowing the great forces on the limb that
can result from a high amount of suction. A "suction liner" or
"roll-on liner" suspension, even in moderate range of suction
provided by the preferred liners, gives the patient the ability to
better control the prosthesis and provides for useful sensory or
proprioceptive feedback. This is because there is a more intimate
connection between the limb and the prosthetic, over much of the
surface area of the limb, compared to old-fashioned waist belts,
distal locks, or other methods. Suction or roll-on liner suspension
also make a prosthesis feel lighter as compared to other forms of
suspension.
[0014] A valve system may be used in combination with a
suction/roll-on suspension system in order to regulate the air
pressure in the socket, so that undesirable pressure differentials
do not prevent or complicate the donning and doffing of the socket.
Conventional valves aim at relieving buildup of pressure when the
lined limb is inserted into the socket, which is typically a snug
fit by design, to prevent a positive pressure inside the socket
relative to outside of the socket (ambient air) and therefore to
allow donning.
[0015] Because the typical valve system is a one-way valve, or
"check valve" that only allows air to be expelled from the socket,
it is intended to maintain a slight negative pressure (slight,
partial suction) relative to ambient once the socket has been
fitted on the residual limb and used. The process of walking and
other weight-bearing will tend to push the limb further into the
socket, but the swing portion of the gait will tend to pull the
socket off the limb. The pushing of the limb further into the
socket may cause the valve to allow air to be expelled, and the
pulling of the socket during the swing portion of the gait will
tend to create suction in the socket because the valve will not
allow air to enter the socket through the valve.
[0016] In applications wherein the multi-layer roll-on liner allows
air to slowly leak into the socket well, as discussed above, or
wherein a seam, connection, lock or other aperture in the socket
allows air to leak into the socket, weight-bearing steps will tend
to expel air from inside the socket through the valve and then said
leaking will tend to replace at least some of it (especially on the
swing of the gait). Therefore, there May be frequent opening and
closing of the valve, perhaps for each, or for many, of the user's
steps. Many conventional valves for these applications are known to
either not work very well, to plug easily, or to make embarrassing
noise with each step as the air is expelled.
[0017] There are many valve systems in use in the market. Typical
valve systems use an inner base that passes from the inside of the
socket to the outside of the socket. The outer housing and the
valve are then threaded onto the inner base or threaded to the
socket wall in an attempt to create an air-tight seal between the
valve and the socket wall. Such systems require a generally flat
socket wall surface for installing the valve and outer housing to
prevent air from leaking out of the socket around the outer housing
instead of being expelled through the valve at the desired air
pressure determined by the one-way valve structure.
[0018] Issued patents and patent publications relating to valve
systems are listed as follows: Underwood (U.S. Pat. No. 1,586,015),
Catranis (U.S. Pat. No. 2,530,285), Sharp et al. (U.S. Pat. No.
2,533,404), Hauser (U.S. Pat. No. 2,790,180), Edwards (U.S. Pat.
No. 4,010,052), Carrow (U.S. Pat. No. 4,106,745), Greene (U.S. Pat.
No. 5,201,774), Hill (U.S. Pat. No. 5,490,537), Hill (U.S. Pat. No.
5,709,017), Slemker et al. (U.S. Pat. No. 6,287,345), Perkins (U.S.
Pat. No. 6,334,876), Hoerner (U.S. Pat. No. 6,361,568), Caspers
(U.S. Pat. No. 6,508,842), Laghi (U.S. Pat. No. 6,544,292), Caspers
(U.S. Pat. No. 6,761,742), Abrogast et al. (U.S. Pat. No.
6,797,008), Caspers (U.S. Publication No. 2004/0181290), and
Patterson et al. (U.S. Publication No. 2004/0260403).
SUMMARY OF THE INVENTION
[0019] The present invention is a valve system for helping to
regulate the air pressure in the space(s) between a residual limb,
or liner-covered limb, and a hard socket of an external prosthesis.
The valve system may be used to regulate said air pressure for
improved donning and doffing the prosthesis, and/or during walking
and other normal use of the prosthesis.
[0020] The preferred valve system comprises a manually-controlled
air outlet and inlet valve that may be installed on a distal region
of a hard socket, and/or an automatic one-way outlet valve. The
manually-controlled valve may be used to open the socket well to
the outside air by providing an air passage from a distal region of
the socket well, so that, when the wearer inserts his/her residual
limb into the socket, air is pushed out through the manual valve
rather than building up pressure inside the socket. Also, when a
user wishes to doff the prosthetic, he/she may manually open the
valve to allow air to flow through the valve into the socket,
equalizing the air pressure inside and outside the socket, for
easier removal of the limb.
[0021] The manually-controlled air outlet and inlet valve is
preferably opened and closed by twisting of a handle portion of the
valve system, wherein partial rotation of the handle portion
relative to the base portion of the valve system creates slight
separation of the handle and base portions to form a gap through
which may pass air from the well of the socket. This simple
twisting, or partial rotation, allows sure and repeatable control
of the valve wherein the valve stays in either the open or closed
position without the user's hand holding the valve in that
position. Thus, after opening the manual valve, the valve stays in
hands-free open status, while the wearer may use his/her hands to
don or doff the prosthesis. The manual valve preferably comprises a
system for preventing the handle and base from becoming entirely
separated during normal use, so that the handle portion does not
fall off of the prosthesis. Also, the manual valve preferably
comprises a stop (s) that limit(s) the amount of relative rotation
of the handle and base portions of the valve, so that the user need
only rotate the handle a small amount, for example, less than 90
degrees, to affect opening or closing the valve. The stop(s) may be
part of the system for preventing the handle and base from entirely
separating, or may be provided in addition to said system for
preventing.
[0022] In one embodiment, the valve system comprises only said
manual valve, while in another embodiment, the valve system
comprises both a manual valve and also an automatic one-way air
outlet valve. In yet another, less-preferred embodiment, the valve
system may comprise only the automatic one-way air outlet
valve.
[0023] In embodiments comprising the automatic air outlet valve;
said automatic valve is a "one-way" or "check" valve, with a valve
stem that "pops" or otherwise opens consistently and quietly at a
small differential pressure, for example, a pressure inside the
socket (in the distal space(s) between said socket and the limb or
liner-covered limb) that is .ltoreq.3 psi pressure above ambient
pressure (outside the socket).
[0024] The valve system, whether it includes only a manual valve,
both manual and automatic valves, or only an automatic valve, are
preferably adhesively mounted on the outside of the socket. Thus,
the valve system is easier to mount than conventional valves due to
this preferred adhesive mounting and due to preferably no part of
the valve being installed from the inside of the socket. The
preferred valve system has no threaded attachment to the socket,
and no portion that extends into the hard socket. The preferred
valve system comprises a base portion that is installed on or near
the outside surface of the hard socket, preferably without threaded
connection between the base and the hard socket. A hole is drilled
in the hard socket from the outside surface of the socket to the
inside surface of the socket, to align the hole in the socket with
the bores/passages in the valve system. The other portions of the
valve system, for example, the handle and the optional one-way
valve structure, are then connected to the base portion, without
said other portions requiring any contact with, or direct
attachment to, the hard socket. Said other portions may be
removable for cleaning, replacement of o-rings or other seals,
and/or for other maintenance without removing the base from the
hard socket.
[0025] The inventors envision, however, that features of the
invented valve system may also be incorporated into a valve that is
attached to a hard socket by other means than are discussed herein
as being preferred. For example, conventional mounting systems for
air expulsion valve in the industry, as discussed in the Related
Art section above, may allow a valve with some of the invented
features of the present invention to be used in a format wherein
the valve is connected to a base that protrudes or resides inside
the hard socket.
[0026] In embodiments comprising a one-way air outlet valve, the
one-way valve stem may have a polygonal side wall, or have other
recesses or grooves in its side wall(s) to create passages through
which air may flow quietly. Alternatively, the valve stem may be
cylindrical and the channel in which the valve stem slides (the
valve housing bore) may be polygonal or have recesses or grooves in
its wall(s), to create passage through which air may flow quietly.
Or, both valve stem and the housing bore may be non-cylindrical.
The preferred low-profile, external-mounting of the valve, and the
quieter action of, and quieter air flow from, the one-way valve as
it "pops" and expels air frequently during walking, may result in a
less intrusive and less noticeable apparatus than is more
acceptable and less embarrassing to wearers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a schematic view of a hard socket and liner
combination, wherein one embodiment of the invented valve is shown
attached to the outside of the hard socket. In this view, the liner
is shown as spaced from the socket, but it will be understood from
the foregoing discussion, that the liner and socket will tend to be
in close contact for at least part of the length along the socket
and preferably all around the circumference of the liner and socket
at or near the top (proximal region) of the socket. Some space
between the liner-covered limb distal end and the socket interior
surface distal end is normally present, so that the limb does not
reach all the way to the distal end of the well of the socket.
[0028] FIG. 1B is a schematic view of a hard socket holding a
residual limb with second generation roll-on liner, with one
embodiment of the invented valve system installed on the hard
socket distal portion. This view illustrates more accurately the
preferred relationship of residual limb, roll-on liner, socket and
valve.
[0029] FIG. 1C is a schematic cross-section detail view of a
two-layer liner on a residual limb RL, such as in FIG. 1B, wherein
the liner has an inner gel-layer G that contacts the residual limb
RL and an outer fabric layer F that adhered to the gel-layer G.
[0030] FIG. 2 is a font perspective view of the valve embodiment of
FIG. 1, which valve embodiment comprises a one-way air outlet valve
but not a manual air inlet and outlet valve.
[0031] FIG. 3 is a front view of the valve embodiment shown in
FIGS. 1 and 2, with a front cover, o-ring/gasket, and spring
removed to better show internals of the valve.
[0032] FIG. 4 is a side view of the valve embodiment shown in FIGS.
1-3.
[0033] FIG. 5 is a cross-sectional side view of the embodiment
shown in FIGS. 1-4, and the valve is shown in the closed
position.
[0034] FIG. 6 is a cross-sectional side view of the embodiment
shown in FIGS. 1-5, wherein the valve is shown in the open position
allowing air to be expelled.
[0035] FIG. 7 is an exploded perspective view of the valve
embodiment shown in FIGS. 1-6.
[0036] FIG. 8 is an alternative embodiment of a valve stem that may
be used in the embodiment of FIGS. 1-7 and that has an o-ring in
its end surface.
[0037] FIG. 9 is a cross-sectional view of an alternative
embodiment of valve system, installed on a hard socket exterior
surface over a hole, wherein the valve system comprises a one-way
outlet valve similar to the embodiment of FIGS. 1-7 and also
comprises one embodiment of the invented manual air inlet and
outlet valve. In FIG. 9, the one-way outlet valve is shown in the
closed position, which means that the pressure inside the socket
well has not reached a level above the ambient pressure that caused
the valve stem to move outward and open the one-way valve passage.
In FIG. 9, the manual valve is in the closed position.
[0038] FIG. 10 is a cross-sectional view of the embodiment of FIG.
9, wherein the manual valve is still in the closed position, but
the one-way outlet valve has opened to allow expulsion of air from
the socket well.
[0039] FIG. 11 is a cross-sectional view of the embodiment of FIGS.
9 and 10, wherein the one-way valve is in the closed position, but
the manual valve has been opened, by turning/rotating the handle
portion relative to the base portion, so that air may enter or exit
the hard socket well from a passageway between said handle portion
and said base portion.
[0040] FIG. 12 is a side view of the embodiment of FIGS. 9-11,
removed from the hard socket, wherein the base portion is shown in
cross-section and the manual valve is shown closed and the one-way
valve is hidden inside the handle portion.
[0041] FIG. 13 is a side view of the embodiment of FIGS. 9-12,
removed from the hard socket, wherein the base portion is shown in
cross-section and the manual valve is opened, and the one-way valve
is hidden inside the handle portion.
[0042] FIG. 14 is a cross-sectional view of an alternative
embodiment of the invented valve system installed on a hard socket
wall over a hole, which valve system comprises a manual valve in
the closed position and which does not comprise a one-way inlet and
outlet valve.
[0043] FIG. 15 is a cross-sectional view of the embodiment of FIG.
14, wherein the handle portion has been turned/rotated to open the
manual valve, so that air may enter or exit the hard socket well
from a passageway between said handle portion and said base
portion.
[0044] FIG. 16 is a cross-sectional view of the embodiment of FIG.
12, viewed along the line 16-16 in FIG. 12, this cross-section
portraying positions of tabs and ramps in a position wherein the
manual valve is closed.
[0045] FIG. 17 is a cross-sectional view of the embodiment of FIGS.
12 and 13, viewed along the line 17-17 in FIG. 13, this
cross-section portraying positions of tabs and ramps in a position
wherein the manual valve is closed.
[0046] FIG. 18 is a side view of the embodiment of FIGS. 14 and 15,
with the handle portion separated from the base portion. In FIG.
18, the external ramps of the handle portion are shown (the one
near the viewer in solid lines and the one hidden from view in
dashed lines) and the cooperating bore and internal ramps of the
base portion are shown in dashed lines.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] In the Figures, there are shown several, but not the only,
embodiments of the preferred valve system for prosthetics. FIGS.
1-8 illustrate an embodiment having only a one-way air outlet
valve. FIGS. 9-11 illustrate an embodiment having both a one-way
air outlet valve and an embodiment of a manual valve. FIGS. 12-18
illustrate an embodiment that having only an embodiment of a manual
valve.
[0048] Referring to embodiments that include a one-way air outlet
valve, it will be understood by one of skill in the art after
reading this application and viewing the drawings, that, once the
air pressure inside the hard socket (relative to the ambient
pressure outside the socket) exceeds the crack pressure of the
one-way valve, the invented one-way or "check" valve opens and air
is expelled out through the valve. This is useful during donning of
the socket, as the insertion of the limb, or liner-covered limb,
increases pressure in the socket well; the one-way valve system
opens to generally equalize the ambient pressure and the pressure
inside the socket in order to allow the donning.
[0049] After donning, when the wearer takes each step, pressure is
exerted downward on the limb, that is, toward the bottom of the
socket well, and this also increases the pressure inside the socket
well. Again, the preferred one-way valve will "crack" or "pop" to
relieve this pressure, and then close when the pressure is
generally equalized by cessation of the downward pressure of the
step, and/or when the swing phase of the gait suspends the
prosthetic from the residual limb/liner and a slight suction/vacuum
(relative to the ambient pressure) tends to be created in the
socket. The preferred valve is designed with a "crack pressure" in
the range of .ltoreq.3 psi differential, and more preferably 1-3
psi, or most preferably 1-2 psi, differential, so that, with this
slight suction/vacuum, and preferably with any pressure
differential below the "set-point" (selected from the range of 1-3,
or 1-2, psi positive pressure inside the socket well, that is, 1-3
or 1-2 psi above the ambient pressure outside the socket well), the
valve will close to not allow air into the socket through the
one-way valve.
[0050] Valve system 10 is adapted to cooperate with a suspension
system 100 for external prosthetic devices, which, as discussed in
the Related Art section, preferably include a liner that provides
at least some blockage/hindrance to air passing between the socket
and the liner. As shown in FIG. 1, the preferred suspension system
100 comprises a liner 103 received on a residual limb, and a hard
socket 105 adapted to fit over the liner 103 and residual limb. The
hard socket 105 comprises a sidewall 110 defining an interior space
I, wherein the sidewall 110 comprises an outer surface 115 and an
inner surface 120.
[0051] The liner 103 is preferably a roll-on liner, and may be of
various types, as discussed in the Related Art section, which
provide varying amounts of "suction." Modern liners comprising both
an inner gel layer and a textile/fabric outer layer are preferred,
and the preferred valve system of the invention cooperates well
with these liners. The valve system embodiments comprising a
one-way air outlet valve are specially adapted to allow air to be
expelled quietly and consistently, even as often as every step, as
may be desired with the amounts of air "leakage" experienced with
fabric-covered liners.
[0052] As shown in FIGS. 2-7, valve system 10 comprises a base 20
having an internally threaded circular bore 22 extending through
the base 20. The base 20 is generally cylindrical in shape and is
preferably fabricated from a durable polymeric material or
"plastic." Alternatively, the base 20 may not comprise threads, but
may instead have other adaptation for joining to the one-way valve
assembly that is inserted and secured to the base. For example, a
bayonet or other latching mechanism that anchors or secures the
valve assembly into the base may be used.
[0053] The base 20 has a generally flat bottom portion 24 and a
slightly curved or rounded top portion 26 (see FIG. 4). The bottom
24 of the base 20 may be slightly concave to mimic the contour of
the outer surface 115 of the socket in the preferred distal
installation area on the socket. See FIGS. 1 and 1B, wherein the
region labeled as "Distal Area" (or D) is indicative of the
preferred, but not the only, region for attachment of the invented
valve system. Distal attachment is preferred, wherein "distal"
broadly refers to attachment of the valve system to the socket in a
region below where the lower-most end of the residual limb will
reach in the socket during use. Distal attachment of the valve
system, however, preferably does not include attachment of the
valve system at the bottom-most point of the socket, as this
location is occupied by the post leading to the prosthetic foot
and/or a distal lock that connects to the lower-most end of the
residual limb.
[0054] With the valve system 10 placed on a distal area of the hard
socket 105, it may expel air as needed even when the residual limb
is nearly fully, or fully, inserted into the socket. Also, in this
area, the valve system 10 is discreet when covered by clothing and
does not protrude (as it would from a more proximal side of the
socket) to catch on clothing or other items.
[0055] After the base 20 is attached to the hard socket 105,
preferably by adhesive, a hole 125 is drilled through the sidewall
110 of the hard socket 105 via the bore 22 in the base 20, so that
the hole 125 generally aligns with the interior bore 22, and bore
32 and opening 62 discussed below, for fluid communication between
the socket well, hole 125, bores 22, 32 and opening 62 to vent air
out of the socket interior I.
[0056] One may see from the drawings that the preferred valve 10
has base 20, o-ring 40, valve housing 30, stem 50 and ring/cover 60
all being coaxial, creating a passageway or "exit path" for air to
pass through when the one-way valve opens. Note that, when fully
assembled, the ring/cover 60 may snap into housing 30 (so that it
can be easily removed for cleaning of the system) or may be
attached to housing 30 by other methods such as adhesive.
[0057] In use, when the air pressure inside the hard socket 105
(between the liner-covered residual limb and the socket interior
surface) exceeds the desired air pressure, as further discussed
below, the air will force the valve stem 50 to move away from the
opening 125 in the hard socket 105, compressing the spring 55
against the ring 60. This movement of the stem 50 unseats the end
54 of the stem from the sealing surface 38, allowing air to flow
around the end 54 and along the sides of the stem to the opening 62
of the ring, and out to the ambient air.
[0058] In other words, the valve system 10 comprises the valve
assembly 11 that is inserted into the base 20, which valve assembly
11 comprises a valve housing 30 having an internal circular bore 32
with a conical sealing surface 38 and an external threaded portion
34. The threaded portion 34 on the valve housing 30 has a slightly
smaller diameter than the threaded bore 22 in the base 20, so that
it may cooperate with the threaded bore 22 in the base 20. As
explained above for the base 20, the valve housing 30 may be
otherwise adapted for connecting/securing to the base. For example,
the valve housing may not have any threads and may instead have
bayonets that are received in slots in the base when the valve
housing is inserted into and rotated in the base.
[0059] The exterior of the valve housing 30 is shown as
"hex-shaped," but other shapes may be used, such as other polygonal
shapes or a cylindrical shape. The hex-shape is preferable as it
may allow the technician to easily install and tighten the valve
housing or the entire assembly in the base. Also, because the
hex-shape provides a good surface to grip, it may allow the user to
manually open the valve, in effect by disassembling the valve
(removing the valve assembly from the base), if necessary, prior to
the user removing his/her residual limb from the hard socket
105.
[0060] An o-ring 40 or other seal is placed in a recess in the base
20 between the base 20 and the valve housing 30. Once the valve
housing 30 is threadably or otherwise received and secured in the
base 20, an air tight seal is created between the base 20 and the
housing 30.
[0061] The valve assembly 11 further comprises a valve stem 50
received in the bore 32 of the housing 30. The valve stem 50 slides
axially inside the bore 32 to seat against the sealing surface 38
of the housing, when the valve is closed, and to move away from and
unseat from the sealing surface 38 when the valve is open. A spring
55 biases the valve stein 50 into the closed, seated position to
close the valve except when a differential air pressure overcomes
the spring 55 bias and pushes the valve stem 50 away from the
sealing surface. Spring 55 is preferably a cylindrical coil
compression spring, the design of which is the main determining
factor in the crack pressure of the valve, and which one of average
skill can design after reading this disclosure.
[0062] The valve assembly, including the bias spring 55, are
adapted so that a differential pressure selected from a certain
amount will "crack" or "pop" open the valve. In other words, the
valve assembly and particularly the spring 55 are preferably
designed so that, when the pressure on the "inner side" of the
valve (to the left in FIGS. 5 and 6, and typically on the inside of
the socket between the liner-covered limb and the interior surface
of the socket at the lower end of the socket) is a certain amount
above the pressure on the "outer side" of the valve (to the right
in FIGS. 5 and 6, and typically outside the socket), then the valve
will open. This "certain amount" is preferably in the range of 1-3
psi, and more preferably in the range of 1-2 psi. As soon as the
differential pressure drops (that is, as soon as the inner pressure
is less than the predetermined amount, preferably 1-3 psi or 1-2
psi, higher than the outer pressure) the spring 55 will again bias
the valve stem 50 to the closed, seated position. Thus, as
discussed above, the valve will open, if necessary, with each step
of the wearer's gait, to allow air to vent from the socket well,
and then quickly close after the air has been vented and/or when
the swing portion of the gait lowers the pressure inside the socket
well.
[0063] The valve stem 50 preferably has an internal bore 52 (or
other hollow or recessed end or cavity that opens to the housing
bore preferably at the spring-end of the valve) that may receive
air that is flowing out of the valve in the "exit path" comprising
passing around the stem, through or around the spring, and out
through the outer end of the valve (at ring 60). Internal bore 52
may provide extra space for this flowing air, as it passes around
or through the spring to exit the valve, thus helping prevent
unpleasant noise or venting sounds that might occur with too-narrow
portions of the exit path. Further, various embodiments of the bore
52 may be advantageous during the molding or machining process, for
weight reduction, and/or for cooperating with or connecting to a
spring or other bias member. The preferred location of the spring
55 places the spring between the flat face 53 of the valve stem 50
and the inner face 63 of the ring 60, and held there securely
enough that it may be repeatedly compressed between those surfaces
and then released, when the valve opens and closes, respectively,
without significantly shifting from its preferred radially-centered
position.
[0064] Further, as shown in FIG. 8, there may be an o-ring 58 or
other material on the generally conical end 54 of the stem 50,
which o-ring 58 or other material is preferably a softer or more
flexible material, compared to the preferred brass or hard plastic
valve stem 50, for enhancing the seal between the stem 50 and the
sealing surface 38. Alternatively, the entire stem 50, the conical
end 54 of the stem, or another portion of the stem may be made of a
softer plastic or other material with enhanced sealing
performance.
[0065] Retaining ring 60 is a generally thin disc that is
friction-fit, snapped, or otherwise secured and anchored into the
bore 32 of the housing 30 to retain the spring 55 and the stem 50
in their proper positions inside the housing. The ring 60 is
preferably secured to the housing, on ledge 39, in such a way that
it will not normally come out of the housing, but that an external
prosthesis technician could pry or otherwise remove it to clean the
valve assembly 11 and/or replace parts of the valve assembly 11.
Ring 60 has an opening 62 through which the air is expelled.
Alternative ways of retaining the valve stem, spring, and/or other
parts as may be desired, in the housings of the valve may be
used.
[0066] The preferred stem 50 is a hexagonal, or other polygonal
shape, so that it has multiple flat or generally flat sides 56.
Therefore, the air may flow along the end 54 of the stem and
through the bore 32 of the housing in between the housing inner
surface and one or more of the flat sides 56. This provides
multiple passages for the air, with each preferably being a
relatively wide passage (that is, radially wider than if the stem
where cylindrical inside a cylindrical housing bore), which is
believed to be important for reducing air-venting noise. These
passages may be said to be "spaced gaps" between the stein and the
housing, in that they are spaced apart (separated) by the edges 57
of the stem, which contact, or come very close to, contacting the
bore 32 surface. These gaps, therefore, may also be called
non-annular gaps or non-annular spaces, as the gap/space between
the stem and the bore of the housing is preferably not simply a
continuous, annular space around the entire stem, but rather
multiple axial passageways that are separated/spaced apart by the
edges 57 that are close to, or that contact, the bore 32. It may
also be said that, because the stem and the housing bore are not
the same shape (and particularly not the same circumferential
shape), there are multiple gaps between the stem and the housing
bore created by this difference in shape. This also places the stem
50 in the housing in a slidable arrangement, where it slides
axially in the housing bore 32, with contact being between the
edges 57 of the sides 56 and the bore 32 surface, but not all the
way around the circumference of the stem. This may be important for
keeping the stem freely slidable in the bore 32 and less prone to
plugging, seizing and/or becoming fouled to an extend that the
valve would make more noise.
[0067] The preferred combination of an axially-sliding stem, and a
polygonal or other stem shape, that provides multiple air passages
along the sides of the stem (which are relatively wide by being
flat, recessed, or otherwise spaced from the preferably cylindrical
housing bore wall) are believed to be at least part of the reason
for the quiet, consistent, and effective operation of the valve.
Also, the preferred low crack pressure that is achievable with the
preferred valve with repeated, consistent operation, is believed to
be important and beneficial for quiet operation and effective
prosthetic suspension without large swings in socket pressure.
[0068] Preferably, the base 20, valve housing 30, and retaining
ring 60 are fabricated from a light-weight durable material, for
example, Delrin.TM. plastic; however, other materials may be used
such as aluminum, titanium, nylon or other plastics. Additionally,
the stem 50 may be hard plastic or brass, but also may be
manufactured from other materials, for example, including other
metals, plastics, or combinations thereof.
[0069] The preferred valve system 10 is adapted to be fitted on the
outside surface 115 of the hard socket 105, and most preferably
only to the outside surface 115. The valve system 10 is preferably
attached with adhesive, by applying adhesive of types known in the
field of prosthetic sockets to the bottom 24 of the base and/or to
the outer surface 115. Other securement means may be used, but
adhesive is preferred as it has been found to be reliable, easy to
use, and not requiring any other fasteners or complex or protruding
parts. Preferably, no portion of the valve system 10 extends
through the socket wall, or into the interior space I of the hard
socket 105, or contacts the inside surface 120 of the hard socket
105. The opening/hole 125 in the socket wall is made by drilling or
otherwise cutting through the socket wall, and this step preferably
does not include any threading or other shaping or preparing of the
socket or the hole therein. Thus, the preferred valve and
attachment of the valve may be used effectively with modern
thin-walled, light-weight sockets. The valve system 10, in the
preferred but not all embodiments, consists essentially only of,
and may consist only of, a base, a valve housing, an o-ring or
other seal, a stem with or without supplemental sealing member or
portion, a spring and a retainer ring or other closure or cover.
This simple design is effective in terms of manufacture,
installation, and operation, and has many benefits over prior art
valves, including over the prior art valves that are more
complicated, prone to plug-up, prone to make venting noise, that
include ball-and-spring systems, and/or that screws/threads into
the socket wall and/or that resides on both sides of the socket
wall. In the preferred embodiment of the invented valve system,
only the base, and more preferably only its bottom surface (24) or
portions of the bottom surface (24), is in contact with the hard
socket.
[0070] Preferred embodiments may be described as a one-way
pressure-control system for a prosthetic hard socket, wherein the
prosthetic socket comprises a wall having an outer surface and an
interior surface defining a well for receiving a residual limb, and
said wall has a hole extending from said outer surface to said
interior surface; and wherein the valve system comprises: a base
connected to said outer surface and having a base bore positioned
over said hole in the wall; and the valve housing being connected
to said base and extending into said base bore and having a housing
bore generally coaxially aligned with said base bore and in fluid
communication with said hole in the socket wall, said valve housing
having a sealing surface; a valve stein received in said housing
bore and slidable into a first, sealed position wherein a portion
of said valve stem (preferably a sealing end) seals against said
sealing surface and into a second, unsealed position away from the
sealing surface; and a spring biasing the valve stem into the
first, sealed position until said air pressure inside the
prosthetic socket well is at a differential pressure in the range
of 1-3 psi greater than ambient pressure outside the socket, at
which time the valve stem is pushed by said differential pressure
into said second, unsealed position so that air leaves the socket
well by flowing through the hole and through the valve system.
Alternatively, or in addition, the valve stem circumference may be
not the same shape as the housing bore circumference (preferably
one of the two being non-circular) so that, when the valve stem is
in the second, unsealed position, air flows around the valve stem
through axial gaps between the valve stem and the housing.
Preferably, this difference in circumference/shape occurs along the
stem side portion, which is the side portion of the stein not
adapted to contact the sealing surface. The axial gaps are
preferably different from simply an annular space all the way
around the stem, and, instead, are axial passages separated by
edges that come close to, or touch the housing bore. These edges'
proximity to the housing bore wall keeps the valve stem generally
centered in the housing bore, while air flows freely past the valve
stein through said axial gaps. Thus, the valve stem may be
described as being shaped so that multiple axial gaps between the
stem and a stem housing extend along the length of the valve stem
to receive air flow when the valve stem is in the second, open
position, and so that said multiple axial gaps are separated by
axial edges of the valve stem that contact or come close to said
stem housing and keep said valve stem generally centered in said
housing. In many embodiments, said valve stem further has a hollow
end with an opening near said spring, wherein said opening is in
communication with the air passageway(s) through the valve,
providing additional space for air to flow or reside, further
reducing air venting noise. The venting of air sooner (at lower
differential) and with less-restricted flow, compared to prior art
vents is believed to be instrumental in reducing or eliminating the
sudden, louder pop, squeak, or sputtering sounds of prior art
devices.
[0071] The invention may also comprise the methods of installing
and using such a valve system. For example, some embodiments of the
invention may comprise a method of installing a pressure-relief
valve in a prosthetic socket, wherein the method comprises:
providing a hard socket; providing a one-way air valve comprising a
base with a base bore, a removable valve stem housing with a
housing bore, valve stem, and a spring; adhesively attaching said
base to the outside of the socket; drilling a hole through the
socket by inserting a drill bit through said base bore and drilling
through the socket to make a hole in the wall generally coaxially
aligned with said bore in the base; inserting and securing said
housing into the base so that the housing bore is generally
coaxially aligned with said base bore and said hole in the wall;
inserting the valve stem and spring into the housing bore so that
said valve stem slides in the housing bore to a closed position and
an open position to allow venting of air out of the socket well
when pressure builds in the socket to a differential pressure that
is greater than ambient pressure. Preferably, the method comprises
no insertion of any part of the air valve into the socket well, and
no part of the air valve extends through the socket wall to reach
the well. Preferably, the only attachment of the air valve to the
socket is adhesive connection of the base to the outer surface of
the socket, and, preferably, there is no threaded attachment of the
air valve to the socket.
[0072] Referred now to FIGS. 9-11, an alternative embodiment
comprises a valve unit 110 that includes a manual valve as well as
a one-way valve. From the cross-sectional view of FIGS. 9 and 10,
one may see that the one-way valve assembly 111 is threadably
connected to a handle 120 that generally serves the same purpose
relative to the valve assembly 111 as base 20 serves to valve
assembly 11, however, handle 120 is not directly attached to the
socket. Instead, handle 120 is preferably expanded in diameter
and/or provided with a flared outer circumference portion, or grip
portion 121, of hexagonal or other polygonal shape, to provide the
user a larger, and preferably easily-rotatable grip surface when
operating the manual valve. Further, instead of having a flat
bottom (or rear surface) that attaches directly to the hard socket,
handle 120 has a rear protrusion 123 that is received in and
operatively connected to base 170. It is base 170 that is directly
connected to the socket, preferably in the same way as discussed
above for the base 20, that is, by adhesive. As discussed in detail
for base 20, base 170 preferably does not connect to, or include,
any structure that reaches through the socket wall or into the
socket well, but rather firmly is glued/adhesively attached to a
distal region of the socket exterior wall surface. As discussed
with base 20, a hole (H in FIGS. 9-11, 14, 15) may be drilled
through the socket wall after attachment of the base 170 to the
socket, or by other means or steps. As may be understood from
discussion of such an attachment, it will be understood that such
an attachment will be effective for a thin-walled socket and will
be convenient and simple compared to more complex mechanisms that
require fasteners or clamps or other structure both on the inside
and the outside of the wall.
[0073] The operative connection of handle 120 (preferably with its
valve assembly 111 including valve casing 111') and the base 170
allow said handle and base to form a manual valve system that is
substantially or entirely independent of the operation of the
one-way valve. Handle 120 is preferably rotatable relative to base
170, and is preferably coaxial with the base 170. Upon rotation, in
one direction, the handle 120 move close to the base 170 to seal
against the base, and, upon rotation in an opposite direction, the
handle 120 moves out away from the base 170 to create a space
between the handle and base that allows air flow between the handle
and base. In the manual valve closed position, shown in FIGS. 9 and
10, the rear surface 124 of the handle grip portion 121 seals to
the front flange 172 of the base 170, most preferably by means of
an o-ring or gasket 174 provided in a groove on the flange 172 or
otherwise retained on the flange. One may see in FIGS. 9 and 10
that the one-way valve assembly 111 may operate as described above
for valve assembly 11 (closed in FIG. 9 and "popped" open in FIG.
10) when the manual valve system is closed, that is, when the
handle 120 and base 170 are in closed, sealed condition. When the
manual valve is closed, the only passageway possible for air exit
through the valve 110 is to pop the one-way valve. It is noteworthy
that, whether the manual valve is closed, air may pass through the
base 170 (through bore 176) and through the rear aperture 125 in
the rear protrusion 123 to reach the one-way valve stem 150, and,
upon opening the stem 150 (as discussed above for stem 50), the air
may flow around the stem and out of the one-way valve assembly via
opening 162. When the manual valve is opened, as discussed below,
air will flow out via the space/gap between the base 170 and the
handle 120, rather than popping the one-way valve, or will flow in
via said space/gap, depending upon the relative pressures inside
the socket and outside the socket.
[0074] The preferred method of operating the manual valve is by
rotation of the handle 120 relative to the base 170, wherein
cooperating structure of the handle and base serves to distance the
handle 120 from the base 170 upon at least a portion of said
rotation. Said cooperating structure preferably comprises at least
one ramp on either of said handle 120 or said base 170 and at least
one riding member on the other of said handle or base, wherein
relative rotation of the handle and base allow the riding member to
"ride" or slide along the ramp to change the relative axial
location of the handle and the base. Said at least one ramp is
slanted so that rotation preferably in the range of 30-270 degrees
(more preferably 30-90 degrees and most preferably 30-70 degrees)
distances the handle from the base enough to unseal the two from
each other for air flow there-between. The riding member may be a
protrusion or ramp. When the riding member is itself a ramp, one
may consider the ramps to cooperate as do threads, but only threads
that allow less than a full rotation. In other words, the handle
may be unscrewed from the base less than a full rotation, so that
the handle movement has an axial component to move the handle
slightly out from the base. The rotational operation of the valve,
in each of the opening direction and the closing direction,
preferably is only a partial rotation (30-270 degrees, more
preferably, a partial rotation in the range of 30-90 and, most
preferably 30-60, degrees). Opening by rotation in the range of
about 30-60 degrees, and closing in the opposite direction by
rotation the same amount (also in the range of 30-60 degrees) is
particularly comfortable and easy to perform, as the user simple
"twists" the handle a short distance one way and then the other.
The especially-preferred operation, therefore, is more like a quick
twist than an screwing/unscrewing a threaded system.
[0075] In the especially-preferred embodiment, two ramps 127, 129
are provided 180 degrees apart on the outer, cylindrical surface
134 of the rear protrusion 123. Two tabs 177, 179 are provided on
the interior cylindrical surface of the bore through base 170, and
extending between the tabs 177 179 on said interior surface are
ramps 181, 182. When the preferred handle 120 is rotated clockwise
relative to the preferred base 170, ramps 181, 182 ride along ramps
127, 129 to pull the handle closer to the base, as if the handle
were being screwed into the base, to an extent that seals the
handle to the base at o-ring/gasket 174. When the preferred handle
120 is rotated counterclockwise relative to the preferred base 170,
ramps 181, 182 ride in the opposite direction along ramps 127, 129
to allow the handle to be slightly distanced from the base, as if
the handle were being unscrewed part-way from the base, to an
extent that unseals the handle from the base at o-ring/gasket 174.
In this open condition, as shown in FIG. 11, air may flow out from
the socket or into the socket through the space S (space S shown in
FIG. 15) between the handle and the base.
[0076] Tabs 177, 179 move, during said rotation, preferably between
limiting structure (L, FIGS. 16 and 17) that is preferably at the
ends of ramps 127, 129. The tabs 177, 179 may move between said
limits L in areas of the outer surface 134 that is recessed
relative to the areas upon which the ramps 127, 129 are
located.
[0077] The handle 120 and base 170 are preferably connected and
disconnectable by means of a snap system, wherein the handle snaps
into the base and then is rotatable relative to the base. In the
preferred embodiments, the handle and base snap together by the
handle being positionable relative to the base in a position
wherein portions of the ramps 181, 182 and/or tabs 177, 179 snap
over slightly-protruding structure on the outer, cylindrical
surface 134 to a point wherein the handle is base is held on the
handle. Preferably, spaces (significantly wider than the tabs 177,
179) exist between the two ramps 127, 129 on the surface 134 (said
relatively recessed areas mentioned above) and, as the two tabs
177, 179 into those recessed spaces, slide, portions of ramps 181,
182 also slide into said spaces and portions of ramps 181, 182 snap
over the cooperating ramps 127, 129 on the handle rear protrusion
outer surface 134. There may be an optional slight protrusion at
the entry of the recessed spaces over which the tabs may snap. When
the tabs slide into the recessed spaces and the ramps 181, 182 snap
over ramps 127, 129, the base ends up in a position relative to the
handle wherein the base is close to, and generally tight against
the handle, and the manual valve is therefore closed. In this
position, the handle and base have snapped together, and are in
position for the ramps to slide along each other to open the manual
valve when the handle is twisted counterclockwise relative to the
base. If substantial pulling on the handle were conducted, the
handle might snap off of the base, this is unlikely to happen
unintentionally, as only twisting is necessary, and not pulling or
pushing, to open and close the manual valve.
[0078] In FIGS. 12-15, and 18, there is shown yet another
embodiment 210, wherein the valve system 210 comprises only a
manual valve and not a one-way air outlet valve. The valve system
210 may be the same as that described above for FIGS. 9-10, but,
instead of the handle having a bore there-through that receives and
cooperates with a one-way valve assembly, the handle 120' is closed
at its front (toward the right in FIGS. 12-15, and 18. The handle
may still have a front, central indent, as portrayed in FIGS. 14
and 15, but this is preferably simply an optional indent or
depression. As in the embodiment of FIGS. 9-11, the embodiments of
FIGS. 12-15 and 18 allows air to flow out of, and into, the socket,
by flowing axially through a portion of the passageway (the portion
in the base) and radially (through the space between the flange of
the base and the rear side of the rear protrusion 123 of the
handle.
[0079] The hard socket is preferably chosen from many conventional
rigid prosthetic sockets currently available on the market. The
suspension and/or connection systems for connection the hard socket
may include locks, straps, and other mechanisms that are available
on the market.
[0080] Although this invention has been described above with
reference to particular means, materials and embodiments, it is to
be understood that the invention is not limited to these disclosed
particulars, but extends instead to all equivalents within the
broad scope of the following claims.
* * * * *