U.S. patent number 3,640,566 [Application Number 04/864,424] was granted by the patent office on 1972-02-08 for invalid chair.
This patent grant is currently assigned to Hodge Distributors Pty. Ltd., Hodge Investments Pty. Ltd.. Invention is credited to George Alwyn Hodge.
United States Patent |
3,640,566 |
Hodge |
February 8, 1972 |
INVALID CHAIR
Abstract
An invalid chair having a seat back hinged to the back of the
seat and a lower frame hinged to the front of the seat to form an
extensible assembly which is pivoted to a main support frame, the
seat being spring loaded in a direction to extend the assembly of
frames so that an invalid is assisted from the seat on to his feet,
the assembly also being positionable in a recumbent position so
that the chair functions as a bed.
Inventors: |
Hodge; George Alwyn (Port
Lincoln, AU) |
Assignee: |
Hodge Investments Pty. Ltd.
(Port Lincoln, AU)
Hodge Distributors Pty. Ltd. (Port Lincoln,
AU)
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Family
ID: |
3731863 |
Appl.
No.: |
04/864,424 |
Filed: |
October 7, 1969 |
Foreign Application Priority Data
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Oct 11, 1968 [AU] |
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44,652/68 |
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Current U.S.
Class: |
297/68; 5/618;
5/81.1R; 5/610; 297/DIG.10 |
Current CPC
Class: |
A61G
5/128 (20161101); A61G 5/006 (20130101); A61G
5/14 (20130101); Y10S 297/10 (20130101) |
Current International
Class: |
A61G
5/14 (20060101); A61G 5/00 (20060101); A47c
001/02 (); A61g 015/00 (); A61g 007/06 () |
Field of
Search: |
;297/68,71,83,86,90,91
;5/60,81 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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711,928 |
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Feb 1931 |
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FR |
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878,022 |
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Sep 1961 |
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GB |
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Primary Examiner: Gilliam; Paul R.
Claims
I claim:
1. A chair having a seat frame, pivot means connecting the rear end
of the seat frame to a back frame, further pivot means connecting
the front end of the seat frame to a lower frame, link means
between the back frame and the lower frame limiting relative
angular relationship therebetween upon tilting of the seat frame, a
footstool, pivot means connecting the footstool to the lower end of
the lower frame, link means between the footstool and a said frame
limiting angular movement of the footstool upon tilting of the seat
frame, said footstool and frames constituting an extensible
assembly which in its extended position has said frames more nearly
in alignment than when in its retracted position, a main support
frame, main pivots between the seat frame and the main support
frame, support brackets on the main frame supporting the seat frame
when said extensible assembly is in its retracted position, a seat
frame lifting lever, pivot means pivotally supporting said lever on
the main frame, means on the lever engaging the under surface of
the seat frame, a tension spring connected at its respective ends
to the lifting lever and the main frame urging the seat frame
upwardly and forwardly thereby in turn urging the frames of said
extensible assembly towards their relatively extended
positions.
2. A chair having a seat frame, a back frame, first hinge means
connecting the back frame to the rear end of the seat frame, a
lower frame, further hinge means connecting the lower frame to the
front end of the seat frame to form with the seat and back frames
an extensible assembly, link means further interconnecting said
frames, a main support frame, main pivots connecting one of the
frames of said extensible assembly to the main support frame, a
seat frame lifting lever, pivot means pivotally supporting said
lever on the main frame, means on the lever engaging an under
surface of the seat frame, and spring means connected to the
lifting lever and to the main frame to urge the seat frame upwardly
and forwardly thereby in turn urging the frames of said extensible
assembly towards their relatively extended positions said link
means includes a link, first pivot means pivotally connecting the
rear end of the link to a downward extension of the back frame, a
second link means including a link arm pivotally connected to the
seat frame and extending downwardly therefrom: further pivot means
operatively and pivotally connecting the front end of the link to
the link arm and including a member pivotally operatively
connecting to the lower frame and to the link arm between its
connections to the seat frame and to the link; the distance between
said first hinge means and said further hinge means being a little
greater than the distance between said first pivot means and said
further pivot means so that the angular relationship between the
back frame and lower frame varies by only a small amount as the
extensible assembly moves from an extended to a retracted
position.
3. A chair according to claim 1 further comprising support brackets
secured to the main frame and positioned to support the seat frame
when in its retracted position, and latch means on the seat frame
and main frame cooperating to releasably retain the seat frame in
its retracted position.
4. A chair according to claim 1 further comprising a pressure
imparting arm, hinge means at the upper end of the pressure
imparting arm hingedly connecting it to the seat frame, a roller
journaled to the lower end of the pressure imparting arm, and a
pressure plate extending rearwardly from the lower frame, said main
pivots being between first said pivot means and said further pivot
means so that the pressure plate is engaged by the pressure roller
only as the frames of said extensible assembly move towards and
into their extended positions.
5. A chair according to claim 4 further comprising a seat back lift
spring connected at one end to said pressure imparting arm and at
the other end to the rear of the main frame, said link means
between the back frame and lower frame being constituted by a link,
pivot means between one end of the link and said pressure imparting
arm and further pivot means between the other end of the link and a
downward extension of said back frame, the seat back lift spring
thereby being extended by movement of the frames of said extensible
assembly into their relative extended recumbent positions.
6. A chair according to claim 2 wherein the link means includes a
link, first pivot means pivotally connecting the rear end of the
link to a downward extension of the back frame, a second link means
including a link arm pivotally connected to the seat frame and
extending downwardly therefrom; further pivot means operatively and
pivotally connecting the front end of the link to the link arm and
including a member pivotally operatively connecting to the lower
frame and to the link arm between its connections to the seat frame
and to the link; the distance between said first hinge means and
said further hinge means being a little greater than the distance
between said first pivot means and said further pivot means so that
the angular relationship between the back frame and lower frame
varies by only a small amount as the extensible assembly moves from
an extended to a retracted position.
Description
This invention relates to a chair which is suitable for general
use, but particularly for use by invalids who have difficulty in
moving their joints and in exercising their limbs, and may include,
but is not limited to a wheel chair.
It is known that arthritics have great difficulty in changing
position, for example from a seated position to a standing
position, and the main object of this invention is to provide a
chair wherein at least some of the weight of a user is
counterbalanced so that the chair will assist a user in changing
from a seated to a standing position.
The invention may in one of its forms consist of a chair having a
seat frame, a back frame hingedly connected to the rear end of the
seat frame, a lower frame hingedly connected to the front end of
the seat frame to form with the seat and back frames an extensible
assembly, link means further interconnecting said frames, a main
support frame, hinge means hingedly connecting one of the frames of
said extensible assembly to the main support frame, and spring
means operatively connecting one of the frames of said extensible
assembly to the main frame and urging the frames of said extensible
assembly towards their relatively extended positions. A chair
constructed according to this invention may be operated with very
little effort by the body movements of a user, and the spring means
will be of assistance to a user moving from a seated to a standing
position, as the frames which constitute the extensible assembly
move correspondingly from a relatively retracted to a relatively
extended position.
It is desirable for an arthritic or other invalid to be able to
exercise legs and ankles while in a seated position, but the
patient's feet should be supported by a footrest. It is of course
desirable that the footrest should not be moveable when the patient
is in a standing position, and further desirable that the footrest
position should be as low as possible so that the step height is
small.
To achieve these objects the invention may although not necessarily
include as one of its further features a relatively moveable
pressure plate on the lower frame engaged by a pressure imparting
member on a link hinged to the seat frame, the pressure imparting
member however being moved out of engagement with the pressure
plate as the seat frame is lowered from an extended to a retracted
position.
When a patient is sitting upright in a chair it is desirable that
the headrest should be in approximately the same plane as the
backrest, but when the patient is lying on a support, it is
desirable that the headrest should be elevated relative to the
backrest, and to achieve this object this invention may include as
a still further feature a headrest frame hinged to a backrest frame
but arranged to be secured thereto in any one of a plurality of
positions.
It will be seen that the invention may be applied either to a
mobile or an immobile chair, and the mobile chair could for example
be a wheelchair arranged to be operated by a patient. However, an
embodiment of the invention when applied to a simple mobile chair
arranged to be operated by a person other than a patient is
described hereunder in some detail with reference to and is
illustrated in the accompanying drawings, in which:
FIG. 1 is a diagrammatic representation of a chair with the frames
of its extensible assembly arranged in a retracted position (for a
patient when seated),
FIG. 2 is a corresponding diagrammatic view showing the frames of
the extensible assembly arranged in an elevated extended position
(for a patient when moving to or from a standing position),
FIG. 3 is a further corresponding diagrammatic view showing the
frames in a horizontal extended position (for a patient in a
recumbent position),
FIG. 4 is an elevation illustrating the frames and linkage
mechanism of the chair,
FIG. 5 is a perspective view of the chair in its elevated extended
position,
FIG. 6 is a fragmentary view of portion of the lower frame of the
chair showing the pressure imparting member firstly in a position
of disengagement from the pressure plate, and secondly in a
position of engagement, and
FIG. 7 is a fragmentary view showing adjustment means for
adjustment of the angle of the back frame relative to the seat
frame.
In this embodiment a main support frame 10 supported by wheels 11
is provided with aligned main pivots 12 one on each side, the main
pivots being disposed forwardly on the main frame 10, and the seat
frame portion of an extensible assembly 13 is pivoted about these
pivots 12 to the main frame, and supported by the pivots.
The extensible assembly 13 comprises a seat frame 16, a back frame
17 hingedly connected to the rear end of the seat frame 16 about
the pivot 18, and a lower frame 19 pivotally connected to the front
end of the seat frame about the pivots 20. The back frame 17
includes a headrest 21, and the lower frame 19 includes a footrest
22. This entire assembly pivots as a whole about the main pivots 12
on the main support frame 10.
A pair of seat frame-lifting levers 26 are pivoted between their
respective ends on the pivots 27 on the main frame 10, the rear
ends being provided with rollers 28 which engage the underface of
the seat frame 16. The front ends are connected to the front ends
of rearwardly and downwardly sloping lifting springs 29 (not shown
in FIG. 3). The rear lower ends of the lifting springs 29 are
anchored to an anchor bar 30 carried by the main frame 10, and
having a position adjustment screw 31 on the end of a crank arm 32,
to provide tension adjustment means which are used to ensure the
lifting spring 29 correctly counterbalances the weight of a
user.
The footrest 22 is hinged near its rear end to the lower frame 19
about pivots 38, the footrest having a rearwardly projecting arm 39
which is connected to a pressure imparting arm 40 by a link 41. The
arm 40 is pivoted at its one end to the main frame 10 about the
main pivot 12, and carries a pressure roller 42 at its lower end,
the arm 40 further being connected to downward extensions 44 of the
back frame 17 by the link 45, which cooperates with the seat frame
16 to form a "parallel arm" type of interconnection between the
back frame 17 and the lower frame 19. As shown in FIGS. 2 and 3,
this retains approximately the same relationship of the frames of
the extensible assembly 13 for the upright and recumbent positions
of a patient, and any required slight variation is arranged by
simply deviating from the parallel conditions.
A seat back lift spring 48 connects the arm 40 to the main frame
10, and becomes extended when the arm 40 moves forwardly as shown
in FIG. 3, so that a patient when in the recumbent position is
assisted from that position to a sitting position by this spring.
The rear face of the lower frame 19 is provided with a pressure
plate 50 which is engaged by the pressure roller 42 carried on the
lower end of the pressure imparting arm, the arrangement being that
the pressure imparting arm prevents swinging of the footrest if the
extensible assembly 13 is extended, but permits swinging of the
footrest if retracted as in FIG. 1, thereby stabilizing the
footrest when a patient is to move outwardly from the chair from a
seated to a standing position. The linkage on the footrest is so
arranged that it lays the footrest over at a comfortable angle for
the feet of a patient when the chair is in any of its positions.
When the upper frame is canted forward from vertical with the seat
frame horizontal, the footrest is free to swing thus enabling the
patient to exercise feet and legs (see FIG. 6).
The rear end of the seat frame is hinged to the upper frame as
described above, and the linkage is such that the upper frame is
sloping forwardly and upwardly when the extensible assembly is in
its extended position but rearwardly and upwardly when it is in its
reclining position. The linkage further lowers the upper frame to
be substantially in the same plane as the seat frame when the chair
is lowered right back for a patient to occupy a horizontal
position.
When the upper frame is in a substantially horizontal position, the
headrest hinged to the upper frame may be adjusted to a slightly
raised position if this is desired.
It is desirable for a patient to be able to regulate the relative
angle between the seat frame and the upper frame and to retain
those two frames at that angle, and to achieve this a notched plate
54 is included on the back frame 17 (FIG. 7) and this is engaged by
a latch 55 on a hand lever 56, the latch 55 simply moving into a
notch to prevent relative movement and being released therefrom to
allow relative movement as the frames vary in their angular
relationship, the latch 55 automatically disengaging from its notch
as the chair moves to its upstanding extended position (FIG. 2) by
engaging a striker plate (not shown) on the frame 10.
To enable the extensible assembly 13 to occupy a retracted
position, the main support frame 10 is provided with support
brackets 57 which support the seat frame in its retracted position,
and are engaged by respective complementary latches 58 (FIG. 4)
coupled to release levers 59 by links 60.
In this embodiment the seat frame is provided with an aperture (not
shown) disposed centrally, and the seat cushion 64 (FIG. 5) is a
loose cushion positioned on the seat frame to cover the aperture,
which is also provided with a lift-out panel (not shown). A shelf
(not shown) is positioned on the main frame but beneath the seat
frame when in its horizontal position, and this then enables the
chair to be used as a commode. The arms may (if desired) be
arranged to retain a table.
* * * * *