U.S. patent number RE30,867 [Application Number 06/135,602] was granted by the patent office on 1982-02-16 for travel chair.
This patent grant is currently assigned to Orthokinetics, Incorporated. Invention is credited to Edward J. Gaffney.
United States Patent |
RE30,867 |
Gaffney |
February 16, 1982 |
Travel chair
Abstract
The front wheel assembly of a wheel chair is dimensioned so that
it will easily pass through the space between the seat of an
automobile and the doorframe thereof. The rear wheel assembly is
retractable upwardly under the seat portion to a position which
permits the seat portion and the retracted rear wheel assembly to
be set upon the automobile seat. The wheel chair and the person
seated therein may be easily placed on the automobile seat and
removed therefrom while the person remains seated in the wheel
chair.
Inventors: |
Gaffney; Edward J. (Pewaukee,
WI) |
Assignee: |
Orthokinetics, Incorporated
(Waukesha, WI)
|
Family
ID: |
26833490 |
Appl.
No.: |
06/135,602 |
Filed: |
March 31, 1980 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
451251 |
Mar 14, 1974 |
03891229 |
Jun 24, 1975 |
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Current U.S.
Class: |
280/642;
297/DIG.4 |
Current CPC
Class: |
A61G
3/06 (20130101); A61G 5/00 (20130101); A61G
5/128 (20161101); A61G 5/1091 (20161101); A61G
5/121 (20161101); A61G 5/1075 (20130101); A61G
5/12 (20130101) |
Current International
Class: |
A61G
3/00 (20060101); A61G 5/00 (20060101); A61G
3/06 (20060101); A61G 5/10 (20060101); A61G
5/12 (20060101); B62B 011/00 () |
Field of
Search: |
;280/642,641,30,643,52,31 ;297/DIG.4 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Song; Robert R.
Attorney, Agent or Firm: Wheeler, House, Fuller &
Hohenfeldt
Claims
I claim:
1. In a wheel chair having a seat portion, a front leg portion, and
a rear wheel assembly, the improvement wherein said front leg
portion is so dimensioned as to be insertable through the space
between the doorframe of an automobile and one of the seats thereof
whereby said front leg portion is placed in support relation to the
automobile and will support the seat portion from the automobile in
the course of subsequent movement of the wheel chair into the
automobile, and .Iadd.retractor .Iaddend.means for .Iadd.assisting
the attendant in .Iaddend.retracting said rear wheel assembly
upwardly independently of any change in the position of the front
leg portion with respect to the seat portion .Iadd.while the front
leg portion is supported on the automobile .Iaddend.and to a
position which clears the space beneath the rear end of the chair
and permits the chair seat portion and retracted rear wheel
assembly to be swung over and set upon said automobile seat.
2. .[.The invention of claim 1.]. .Iadd.In a wheel chair having a
seat portion, a front leg portion, and a rear wheel assembly, the
improvement wherein said front leg portion is so dimensioned as to
be insertable through the space between the doorframe of an
automobile and one of the seats thereof whereby said front leg
portion is placed in support relation to the automobile and will
support the seat portion from the automobile in the course of
subsequent movement of the wheel chair into the automobile, and
means for retracting said rear wheel assembly upwardly
independently of any change in the position of the front leg
portion with respect to the seat portion and to a position which
clears the space beneath the rear end of the chair and permits the
chair seat portion and retracted rear wheel assembly to be swung
over and set upon said automobile seat, and .Iaddend.wherein said
wheel chair has a chair frame including back portion extending
upwardly from said seat portion and a front leg portion extending
downwardly from said seat portion, and wherein said rear wheel
assembly includes a rear wheel frame that extends forwardly from
said rear wheels and wherein said means for retracting said rear
wheel assembly includes means pivotally connecting the front of
said rear wheel frame to said chair frame, and a retractable strut
connecting between said rear wheel assembly and said chair frame to
support the wheel chair on the rear wheel assembly and to retract
the rear wheel assembly upwardly under the chair seat portion by
swinging said rear wheel frame upwardly.
3. .[.The invention of claim 2.]. .Iadd.In a wheel chair having a
seat portion, a front leg portion, and a rear wheel assembly, the
improvement wherein said front leg portion is so dimensioned as to
be insertable through the space between the doorframe of an
automobile and one of the seats thereof whereby said front leg
portion is placed in support relation to the automobile and will
support the seat portion from the automobile in the course of
subsequent movement of the wheel chair into the automobile, and
means for retracting said rear wheel assembly upwardly
independently of any change in the position of the front leg
portion with respect to the seat portion and to a position which
clears the space beneath the rear end of the chair and permits the
chair seat portion and retracted rear wheel assembly to be swung
over and set upon said automobile seat, and wherein said wheel
chair has a chair frame including back portion extending upwardly
from said seat portion and a front leg portion extending downwardly
from said seat portion, and wherein said rear wheel assembly
includes a rear wheel frame that extends forwardly from said rear
wheels and wherein said means for retracting said rear wheel
assembly includes means pivotally connecting the front of said rear
wheel frame to said chair frame, and a retractable strut connecting
between said rear wheel assembly and said chair frame to support
the wheel chair on the rear wheel assembly and to retract the rear
wheel assembly upwardly under the chair seat portion by swinging
said rear wheel frame upwardly, and .Iaddend.wherein said rear
wheel frame comprises an upwardly arched undercarriage extending
between said chair frame and rear wheels.
4. .[.The invention of claim 3.]. .Iadd.In a wheel chair having a
seat portion, a front leg portion, and a rear wheel assembly, the
improvement wherein said front leg portion is so dimensioned as to
be insertable through the space between the doorframe of an
automobile and one of the seats thereof whereby said front leg
portion is placed in support relation to the automobile and will
support the seat portion from the automobile in the course of
subsequent movement of the wheel chair into the automobile, and
means for retracting said rear wheel assembly upwardly
independently of any change in the position of the front leg
portion with respect to the seat portion and to a position which
clears the space beneath the rear end of the chair and permits the
chair seat portion and retracted rear wheel assembly to be swung
over and set upon said automobile seat, and wherein said wheel
chair has a chair frame including back portion extending upwardly
from said seat portion and a front leg portion extending downwardly
from said seat portion, and wherein said rear wheel assembly
includes a rear wheel frame that extends forwardly from said rear
wheels and wherein said means for retracting said rear wheel
assembly includes means pivotally connecting the front of said rear
wheel frame to said chair frame, and a retractable strut connecting
between said rear wheel assembly and said chair frame to support
the wheel chair on the rear wheel assembly and to retract the rear
wheel assembly upwardly under the chair seat portion by swinging
said rear wheel frame upwardly, and wherein said rear wheel frame
comprises an upwardly arched undercarriage extending between said
chair frame and rear wheels, and .Iaddend.wherein the arch of said
undercarriage substantially matches the angle between said seat
portion and said front leg portion whereby said undercarriage
swings into close proximity to said leg portion and seat portion
when said rear wheel assembly is retracted.
5. .[.The invention of claim 3.]. g In a wheel chair having a seat
portion, a front leg portion, and a rear wheel assembly, the
improvement wherein said front leg portion is so dimensioned as to
be insertable through the space between the doorframe of an
automobile and one of the seats thereof whereby said front leg
portion is placed in support relation to the automobile and will
support the seat portion from the automobile in the course of
subsequent movement of the wheel chair into the automobile, and
means for retracting said rear wheel assembly upwardly
independently of any change in the position of the front leg
portion with respect to the seat portion and to a position which
clears the space beneath the rear end of the chair and permits the
chair seat portion and retracted rear wheel assembly to be swung
over and set upon said automobile seat, and wherein said wheel
chair has a chair frame including back portion extending upwardly
from said seat portion and a front leg portion extending downwardly
from said seat portion, and wherein said rear wheel assembly
includes a rear wheel frame that extends forwardly from said rear
wheels and wherein said means for retracting said rear wheel
assembly includes means pivotally connecting the front of said rear
wheel frame to said chair frame, and a retractable strut connecting
between said rear wheel assembly and said chair frame to support
the wheel chair on the rear wheel assembly and to retract the rear
wheel assembly upwardly under the chair seat portion by swinging
said rear wheel frame upwardly, and wherein said rear wheel frame
comprises an upwardly arched undercarriage extending between said
chair frame and rear wheels, and wherein said chair frame comprises
spaced support tubes, said upwardly arched undercarriage fitting
between said tubes when the undercarriage is retracted.
6. The invention of claim 2 wherein said retractable strut
comprises a telescoping tube assembly comprising an inner tube
which is connected at its top to said back portion and extends
downwardly therefrom, an outer tube which surrounds said inner tube
and is slidably attached to the top thereof, an intermediate tube
which is connected at its bottom end to said rear wheel assembly
and projects upwardly therefrom, said intermediate tube being
slidably contained between said inner tube and said outer tube, a
latch plunger attached within said inner tube and projecting
radially therefrom, and a first and second latch opening in said
intermediate tube, said first opening being positioned to engage
said latch plunger when said telescoping tube assembly is in its
extended position, and said second opening being positioned to
engage said latch plunger when said telescoping tube assembly is in
its retracted position.
7. The invention of claim 6 wherein said outer tube is provided
with a latch plunger cam opposite said latch plunger whereby
displacement of said outer tube with respect to the inner tube will
cam actuate the latch plunger, thereby unlatching said latch
plunger from said first or second latch opening and freeing said
intermediate tube for movement.
8. .[.The invention of claim 2.]. .Iadd.In a wheel chair having a
seat portion, a front leg portion, and a rear wheel assembly, the
improvement wherein said front leg portion is so dimensioned as to
be insertable through the space between the doorframe of an
automobile and one of the seats thereof whereby said front leg
portion is placed in support relation to the automobile and will
support the seat portion from the automobile in the course of
subsequent movement of the wheel chair into the automobile, and
means for retracting said rear wheel assembly upwardly
independently of any change in the position of the front leg
portion with respect to the seat portion and to a position which
clears the space beneath the rear end of the chair and permits the
chair seat portion and retracted rear wheel assembly to be swung
over and set upon said automobile seat, and wherein said wheel
chair has a chair frame including back portion extending upwardly
from said seat portion and a front leg portion extending downwardly
from said seat portion, and wherein said rear wheel assembly
includes a rear wheel frame that extends forwardly from said rear
wheels and wherein said means for retracting said rear wheel
assembly includes means pivotally connecting the front of said rear
wheel frame to said chair frame, and retractable strut connecting
between said rear wheel assembly and said chair frame to support
the wheel chair on the rear wheel assembly and to retract the rear
wheel assembly upwardly under the chair seat portion by swinging
said rear wheel frame upwardly, and .Iaddend.wherein said rear
wheel frame is arched between said front wheel assembly and rear
wheels, a leg attached to said rear wheel frame in the arched
portion thereof and positioned to rest upon the automobile door
sill to support the wheel chair and its occupant during the time
period in which said rear wheel assembly is being retracted,
whereby the downward pressure due to the weight of said occupant on
the pivotal connection between said front leg portion and rear
wheel frame causes the rear wheel frame to pivot upwardly toward
its retracted position.
9. .[.The invention of claim 2.]. .Iadd.In a wheel chair having a
seat portion, a front leg portion, and a rear wheel assembly, the
improvement wherein said front leg portion is so dimensioned as to
be insertable through the space between the doorframe of an
automobile and one of the seats thereof whereby said front leg
portion is placed in support relation to the automobile and will
support the seat portion from the automobile in the course of
subsequent movement of the wheel chair into the automobile, and
means for retracting said rear wheel assembly upwardly
independently of any change in the position of the front leg
portion with respect to the seat portion and to a position which
clears the space beneath the rear end of the chair and permits the
chair seat portion and retracted rear wheel assembly to be swung
over and set upon said automobile seat, and wherein said wheel
chair has a chair frame including back portion extending upwardly
from said seat portion and a front leg portion extending downwardly
from said seat portion, and wherein said rear wheel assembly
includes a rear wheel frame that extends forwardly from said rear
wheels and wherein said means for retracting said rear wheel
assembly includes means pivotally connecting the front of said rear
wheel frame to said chair frame, and a retractable strut connecting
between said rear wheel assembly and said chair frame to support
the wheel chair on the rear wheel assembly and to retract the rear
wheel assembly upwardly under the chair seat portion by swinging
said rear wheel frame upwardly, .Iaddend.and further comprising
spring means connected between said seat portion and said rear
wheel frame for urging said rear wheel frame upwardly under said
seat portion, and latch means on said retractable strut for
latching the same in an extended position to support said rear
wheel frame in a lowered position against the urging of said spring
means, and means for unlatching said latch means to permit said
spring means to lift said rear wheel assembly into a retracted
position under said seat portion.
10. .[.The invention of claim 2.]. .Iadd.In a wheel chair having a
seat portion, a front leg portion, and a rear wheel assembly, the
improvement wherein said front leg portion is so dimensioned as to
be insertable through the space between the doorframe of an
automobile and one of the seats thereof whereby said front leg
portion is placed in support relation to the automobile and will
support the seat portion from the automobile in the course of
subsequent movement of the wheel chair into the automobile, and
means for retracting said rear wheel assembly upwardly
independently of any change in the position of the front leg
portion with respect to the seat portion and to a position which
clears the space beneath the rear end of the chair and permits the
chair seat portion and retracted rear wheel assembly to be swung
over and set upon said automobile seat, and wherein said wheel
chair has a chair frame including back portion extending upwardly
from said seat portion and a front leg portion extending downwardly
from said seat portion, and wherein said rear wheel assembly
includes a rear wheel frame that extends forwardly from said rear
wheels and wherein said means for retracting said rear wheel
assembly includes means pivotally connecting the front of said rear
wheel frame to said chair frame, and a retractable strut connecting
between said rear wheel assembly and said chair frame to support
the wheel chair on the rear wheel assembly and to retract the rear
wheel assembly upwardly under the chair seat portion by swinging
said rear wheel frame upwardly, and .Iaddend.wherein said rear
wheel assembly includes an axle, said axle being rigidly attached
to said rear wheel frame, and further comprising a right angle bend
in said rear wheel frame in front of said axle for placing the rear
wheels above the bottom of said seat portion in the retracted
position of said rear wheel assembly.
11. The invention of claim 1 in which said front leg portion
includes a wheel assembly narrow enough to pass through said space.
Description
BACKGROUND OF THE INVENTION
This invention relates to wheel chairs, particularly for children.
In the past, when a wheel chair bound person was to be driven from
one place to another in a standard passenger automobile, it was
necessary to move the wheel chair adjacent to the automobile and
then transfer the disabled person from the wheel chair seat to the
automobile seat. Special folding wheel chairs were used which could
be folded up and carried in the automobile. When the destination
was reached, the folding wheel chair was taken out, unfolded,
placed next to the automobile and then the disabled person was
transferred from the automobile seat to the wheel chair seat. This
procedure is difficult and time consuming, both for the disabled
person and the person assisting him. As a result, wheel chair bound
persons are usually only transported by automobile when it is
necessary to do so. In accordance with this invention, however, a
novel wheel chair has been devised which greatly simplifies the
process of moving a wheel chair bound person by automobile.
SUMMARY OF THE INVENTION
In accordance with the present invention, the wheel chair travels
with the patient, who never leaves the wheel chair. The
undercarriage of the wheel chair is foldable to facilitate
maneuvering the chair through the automobile door. In its folded
position, the wheel chair is supported on the automobile seat. For
these purposes, the front wheel assembly of the wheel chair is
dimensioned so that it will easily pass through the space between
the seat of an automobile and the doorframe thereof. The rear wheel
assembly is retractable upwardly under the seat portion to a
position which permits the seat portion and the retracted rear
wheel assembly to be set upon the automobile seat. The
undercarriage is arched by bowing it upwardly, so that it will
clear the front edge of the automobile seat. The wheel chair and
the person seated therein may be easily placed on the automobile
seat and removed therefrom while the person remains seated in the
wheel chair.
Other objects, features and advantages of the invention will appear
from the disclosure hereof.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of a wheel chair embodying the
invention.
FIG. 2 is a rear perspective view of the embodiment shown in FIG.
1.
FIG. 3 is an enlarged fragmentary longitudinal sectional detail
view of the latching mechanism for the embodiment shown in FIGS. 1
and 2.
FIG. 4 is a side elevation view of the embodiment shown in FIGS.
1-3.
FIG. 5 is a side elevation view of another embodiment of the
invention.
FIG. 6 is a perspective view showing the first step in placing the
chair of FIGS. 1-4, along with its passenger, on an automobile
seat.
FIG. 7 is a perspective view showing the second step in placing the
chair of FIGS. 1-4, along with its passenger, on an automobile
seat.
FIG. 8 is a perspective view showing the third step in placing the
chair of FIGS. 1-4, along with its passenger, on an automobile
seat.
FIG. 9 is a fragmentary longitudinal sectional view taken along the
line 9--9 of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Although the disclosure hereof is detailed and exact to enable
those skilled in the art to practice the invention, the physical
embodiments herein disclosed merely exemplify the invention which
may be embodied in other specific structure. The scope of the
invention is defined in the claims appended hereto.
FIGS. 1-4 show the structure of a preferred embodiment of folding
wheel chair and FIGS. 6-8 show how this embodiment is placed on an
automobile seat. Referring to FIGS. 1-4, this embodiment includes a
seat portion 10 which is supported by a seat frame described
hereinafter, a front wheel assembly 12, and a rear wheel assembly
14. The front wheel assembly 12 is dimensioned so that it will
easily pass through the space 16 (FIG. 6) between a seat 18 of an
automobile and the doorframe 20 thereof. It may consist of a single
wheel or two closely spaced wheels 50 as illustrated herein. The
rear wheel assembly 14 is retractable upwardly under the seat
portion 10 to a position (FIG. 8) which permits seat portion 10 and
rear wheel assembly 14 to be set upon automobile seat 18, which may
be either a front seat or a rear seat.
The chair frame 23 desirably comprises two chrome-plated steel
tubes 24 (FIG. 4) which are bent at 25, 26, 28 and 30 and are
joined together at their upper extremities by a chrome-plated steel
crossbar tube 32 (FIG. 2). The portion of tubes 24 between bends 25
and 26 constitutes the front leg portion of the seat frame and
supports a molded plastic footrest 36 which is clamped to tubes 24
by conventional means not shown and is adjustable in its position
along the front leg portion of tubes 24. The portion of tubes 24
between bends 26 and 28 constitutes the seat portion of the seat
frame and supports a conventional upholstered seat 38. Seat 38 is
supported at its front margin by a rectangular, chrome-plated steel
crossbar 40 (FIG. 1) that rests upon tubes 24 and is attached
thereto by conventional means not shown. At its rear margin, seat
38 is supported by the tubes 24 and is attached thereto by
conventional means not shown. The portion of tubes 24 between bends
28 and 30 constitutes the back portion of the seat frame and
supports a conventional flexible fabric or plastic back panel 42
which spans between the spaced tubes 24. A pair of adjustable head
support pads 44 are optionally attached between tubes 24 over back
42. A pair of bent, chrome-plated steel tubes 46 are connected by
conventional means between the ends of crossbar 40 and the back
portion of tubes 24 to help support the back portion and serve as
arm rests. Arm rest cushions may be attached over the top of tubes
46, if desired.
At the forward ends of tubes 24, beyond the bend 25, a front wheel
assembly 12 comprising a rectangular, chrome-plated steel box 48,
and a pair of front wheels 50 with caster brackets 52 is attached.
Box 48 is welded to the bottom ends of tubes 24 and caster brackets
52 are pivotally connected thereto by conventional means not shown.
Front wheel assembly 12 is dimensioned to easily pass through the
space 16 (FIG. 6) between a seat 18 of an automobile and the
doorframe 20 thereof. For this purpose the wheels 52 are relatively
small and are spaced relatively close together. The fact that angle
A of bend 26 (FIG. 4) is an obtuse angle also helps in passing
wheel assembly 12 through space 16 because the obtuse angle A
extends and spaces front wheel assembly 12 substantially ahead of
seat portion 10. This facilitates passing front wheel assembly 12
into and through the space 16, while the patient 17 is still
outside of the automobile. The larger the size of angle A, the less
degree of tilt is required in the back portion of the chair in the
course of inserting front wheel assembly 12 through space 16. For
the sake of appearance and to limit the length of the chair, angle
A is preferably selected to be in the neighborhood of 125.degree..
This value, however, is an example rather than a limitation,
inasmuch as the value selected for angle A can be varied within
reasonable limits without changing the basic structure of the wheel
chair.
The rear wheel assembly 14 is mounted on a pivoted wheel frame or
undercarriage 53 which comprises a pair of upwardly bowed or arched
chrome-plated steel tubes 54 (FIG. 4) which are pivotally connected
at their front end to tubes 25 by conventional means including a
pivot pin 56 which extends through suitable journal openings in
tubes 24 and 54. Tubes 54 of undercarriage 53 are bent upwardly at
58 to form an arch intermediate front wheel assembly 12 and the
rear wheels 22. Tubes 54 are also bent at 60 and are joined
together at their rear end by a chrome-plated steel axle 62 upon
which the rear wheels 22 are journaled. Tubes 54 are also joined
together by a chrome-plated steel crossbrace 64 which spans between
tubes 54 immediately in front of rear wheels 22.
The arch 58 in tubes 54 is spaced approximately the same distance
from pivot pin 56 as the bend 26 in tubes 24 and the angle B of
bend 58 is approximately the same size as the angle A of bend 26.
The tubes 54 are, however, spaced closer together than the tubes
24. Therefore, when the undercarriage including rear wheel assembly
14 is retracted upwardly so that the rear wheels 22 occupy the
dashed line position indicated at 66 in FIG. 4, the tubes 54 of
undercarriage 53 will interfit flush between the tubes 24 of chair
frame 23. This geometry is desirable but not essential, inasmuch as
will be shown hereinafter in connection with a second embodiment
(FIG. 5), the chair will still fit on the automobile seat 18 when
the values for angles A and B are different.
The chair frame tubes 24 are supported above the undercarriage
frame tubes 54 by a chrome-plated steel telescoping tube assembly
68 which functions as a retractable strut and which is welded at
its top end to crossbar 32 and is welded at its bottom end to axle
62. When strut 68 is extended and locked, it supports chair frame
tubes 24 in the full line position of parts indicated in FIG. 4. To
retract undercarriage 53, to place the wheel chair on an automobile
seat, strut 68 may be telescoped or retracted, whereupon the
undercarriage parts will assume their position shown in broken
lines in FIG. 4.
The retraction of undercarriage 53 is desirably powered by spring
70, which is connected between crossbrace 40 and crossbrace 64.
When the latch 93 for strut 68 is released, spring 70 draws rear
wheel assembly 14 upwardly until rear wheels 22 occupy the position
indicated by dashed lines 66 in FIG. 4. In this position, rear
wheel frame tubes 54 interfit flush with seat frame tubes 24 and
the chair seat portion 10 and retracted rear wheel assembly 14 may
be set upon an automobile seat as shown in FIG. 8. Because of bend
60 in tube 54, rear wheels 22 clear the bottom of seat portion 10
in the retracted position.
Telescoping tube assembly or strut 68 includes a chrome-plated
steel inner tube 72, which is welded to crossbrace 32 and depends
downwardly therefrom. Inner tube 72 is surrounded by chrome-plated
steel outer tube 74, which serves as a latch actuator, and a
chrome-plated steel intermediate tube 76, which is welded to axle
62 and projects upwardly therefrom and is slidably engaged between
inner tube 72 and outer tube 74. A sleeve bushing 75 is attached to
inner tube 72 and slidably engages outer tube 74. As best shown in
FIG. 9, a pin 78 spans across the outer tube 74, near its top end,
and rides in longitudinally extending slots 80 formed near the top
end of inner tube 72. A compression spring 82 within the top end of
inner tube 72 urges pin 78 and outer tube 74 downwardly. Thus outer
tube 74 is slidably connected to inner tube 72 by pin 78 and spring
82 and may be moved upwardly and downwardly with respect to inner
tube 72.
A laterally projecting hollow handle 84 (FIG. 3) containing a
spring loaded latch plunger 86 is welded on one side of the top
portion of outer tube 74 and a coaxial solid handle 88 is welded to
the other side of tube 74. A spherical knob 90 is attached to the
outer end of latch plunger 86 to enable the same to be manually
drawn outwardly. Latch plunger 86 normally extends through a
circular opening 92 (FIG. 9) in inner tube 72 to latch outer tube
74 thereto. When plunger 86 is manually drawn outwardly, it
releases outer tube 74 for up and down movement relative to inner
tube 72.
At the bottom end of inner tube 72, a latch detent plunger 94
normally latches inner strut tube 72 to intermediate strut tube 76,
thus to hold the strut 68 in extended position. Detent plunger 94
is guided for lateral movement in socket 93 formed in the side wall
of tube 72, near its lower end. Detent 94 is spring loaded
outwardly toward engagement with an opening 98 formed in the side
wall of intermediate tube 76, near its top, by a U-shaped spring
96. When thus engaged, detent 94 latches tube assembly 68 in its
extended position. Withdrawal of detent 94 from opening 98 releases
intermediate tube 76 to be slid upwardly between inner tube 72 and
outer tube 74 until opening 100 near the lower end of strut tube 76
comes opposite spring-biased detent 94, whereupon spring 96
advances detent 94 into engagement with opening 100 and locks the
tube assembly 68 in its retracted position. Outer tube or sleeve 74
is used as a latch actuator. For this purpose, it is provided with
a cam dimple 102 aligned with detent 94 when latch plunger 86 locks
tubes 72, 74 together. In this position (FIG. 3), the relief
provided by dimple 102 allows detent 94 to fully engage into
opening 98.
To unlatch tube assembly 68, the operator grasps knob 90 and pulls
it outwardly. This disengages plunger 86 from opening 92 in inner
tube 72 and frees outer tube 74 for up and down movement with
respect to inner tube 72. The operator then draws handle 84
upwardly, which causes the dimple 102 to cam against the rounded
end of detent 94 and force it inwardly until its rounded end is
within opening 98 in tube 76. Any slight upward pressure on tube 76
will now cam the edges of opening 98 against the rounded end of
detent 94 to complete its retraction and allow tube 76 to telescope
into tube 74.
The upward pressure of spring 70 (FIG. 2) on axle 62 is sufficient
to complete retraction of detent 94 and cause tube 76 to slide
upwardly between tubes 72 and 74, thereby telescoping or retracting
tube assembly 68. When tube 76 reaches its upward limit of
movement, opening 100 aligns with detent plunger 94 which advances
under pressure of spring 96 to latch tube assembly 68 in its
telescoped or retracted position.
The wheel chair and patient can then be placed on an automobile
seat, as hereinafter described. When the wheel chair is removed
from the automobile, it is necessary to move tube assembly or strut
68 from its retracted position to its extended position. This is
done by first unlatching intermediate tube 76 for movement in the
manner described above. Next, the operator places his foot on axle
62 and forces tube 76 downwardly until opening 98 re-engages
plunger 94 to latch telescoping tube assembly or strut 68 in its
extended position.
FIGS. 6-8 show how the above-described wheel chair and patient may
be maneuvered into and out of an automobile without removing the
patient from the chair. Although a child patient 17 is shown in the
wheel chair in FIGS. 6-8, it should be understood that the wheel
chair of this invention may be sized for either children or adults.
The process of loading and unloading is the same in either
case.
First, the wheel chair is moved by attendant 69 to the side of the
automobile adjacent to the open door with the front wheel assembly
12 of the wheel chair facing the front of the automobile.
Next, the wheel chair is tipped back on its rear wheel assembly 14
as shown in FIG. 6 and is moved forward to pass front wheel
assembly 12 through the space 16 between seat 18 and doorframe 20.
The front wheels 50 are set down on the floor of the automobile and
the forward ends of chair frame 24 may rest on the door sill
21.
Next, the telescoping tube assembly or strut 68 is unlatched, in
the manner described above. For this purpose the attendant 69 will
typically steady the chair with one hand on a hand grip 30, while
using his other hand to retract latch knob 90. The undercarriage 53
and rear wheels 22 will be raised by spring 70 to the retracted
position shown in FIGS. 4 and 7. While rear wheels 22 are being
raised, the weight of the wheel chair and the occupant thereof is
supported in the front by the front wheel assembly 12 and/or the
bearing of seat frame 24 on the door sill 21 and in the rear by the
attendant. As soon as the undercarriage 53 and rear wheels 22 are
raised, the wheel chair is moved sideways until the seat portion 10
and retracted wheels 22 rest on top of the automobile seat 18, as
shown in FIG. 8. A seat belt may then be placed around the patient
while he remains seated in the chair. The upward arch 58 of
undercarriage 53 clears the undercarriage 53 from interference with
the seat 18 so that the chair receives firm support from its rear
wheels 22 and/or the rear ends of the undercarriage which have
broad-based contact with the seat. The front end of the chair
receives firm support from the automobile floor. The undercarriage
has no intermediate contact with the seat 18, thus to avoid any
tendency to tip or rock thereabout.
To remove the wheel chair and its occupant from the automobile, the
seat belt is first unbuckled, then the rear end of the wheel chair
is moved away from automobile seat 18 until the rear wheels 22 are
clear of seat 18 as shown in FIG. 7. Then the attendant unlatches
the telescoping tube assembly 68 in the manner described above and
places his foot on axle 62 and pushes it down to extend tube
assembly 68 to the position shown in FIG. 6 and latch it in this
position. The rear wheels 22 are then placed on the ground and the
wheel chair is tilted backward until the front wheel assembly 12 is
clear of the automobile sill and can be withdrawn therefrom and
lowered into contact with the ground.
It will be clear from the foregoing that the procedure for placing
the wheel chair of this invention into an automobile and for
removing it therefrom is much simpler and more convenient and less
stressful to the patient than the procedure used in the prior art,
which involved switching the patient from the chair to the
automobile seat and then folding and carrying the chair
separately.
The chair embodiment illustrated in FIGS. 1-4 is preferably
equipped with a brake rod 104 (FIGS. 1 and 2) which is movably
mounted on a bracket 106 which is attached to axle 62. Brake rod
104 extends parallel to axle 62 adjacent to the tires of rear
wheels 22 and can be pressed against the tires by a conventional
foot pedal 108 to lock rear wheels 22 in one position. This brake
mechanism may be used when the wheel chair is parked on a slope or
in other situations where it is desirable to keep the wheel chair
from moving.
FIG. 5 shows another embodiment of the invention in which a seat
portion 110 and back portion 112 are supported by a pair of
chrome-plated steel tubes 114 which are bent at right angles at
116. The front leg portion 118 of this embodiment is formed by
another pair of chrome-plated steel tubes 120 which are welded to
tubes 114 at 122 and project downwardly therefrom at an obtuse
angle C to the bottom of seat portion 110. In this embodiment, the
front wheel assembly 124 is not rigidly attached to the leg tubes
120. Instead, it is rigidly attached to a pair of chrome-plated
steel tubes 126 which extend between front wheel assembly 124 and
rear wheel assembly 128. Tubes 120 are pivotally connected to
undercarriage tubes 126 by a pin 127 near the front wheel assembly
124. Undercarriage tubes 126 are bent at 130 at an angle D which is
slightly larger than angle C and are bent at 132 near axle 134,
which is rigidly connected therebetween. A crossbrace 136 is
connected between the rear of tubes 126 and a telescoping tube
assembly or strut 140 is connected to crossbrace 136 at its bottom
and is connected to back portion 112 at its top.
When it is desired to retract undercarriage 126 and rear wheels
142, telescoping tube assembly 140 can be telescoped or retracted
in the same manner previously described, to permit wheels 142 to be
raised to the position 146 indicated by the dashed lines in FIG. 5.
Telescoping tube assembly 140 is the same as tube assembly 68 and
may be extended and retracted in the same manner.
In this embodiment, a pair of downwardly projecting stub legs 148
having rubber caps 150 at their lower ends are welded to tubes 126
between front wheel assembly 124 and rear wheel assembly 128. Legs
148 are of such length and are so positioned as to rest upon the
front door sill of an automobile when the wheel chair is being
loaded into the automobile to help support the wheel chair during
loading and unloading. However, legs 148 are not long enough to
interfere with placing the wheel chair on the automobile seat. As
shown in FIG. 8, there is enough room between the chair frame and
the automobile seat 18 to accommodate the legs 148.
In loading the embodiment of FIG. 5 on the seat of an automobile,
the legs 148 are rested on the automobile door sill in the first
step of the procedure, with the front wheel assembly 124 being held
above the floorboards. Then the telescoping tube assembly 140 is
unlatched, and the weight of the wheel chair and occupant thereof
is supported by the legs 148. The pressure caused by the weight of
the occupant on pivot pin 127 then causes the undercarriage tubes
126 to rotate upwardly to the retracted position shown by the
dashed line in FIG. 5. Telescoping tube assembly 140 is then
latched in its retracted position. Next, the chair is tilted
forwardly to engage the front wheel assembly 124 on the floorboards
and the seat portion 110 is lifted and moved sideways onto the
automobile seat.
In unloading this embodiment, the rear wheel assembly 128 does not
have to be pushed down since it will fall due to the force of
gravity when telescoping tube assembly 140 is unlatched.
In all embodiments of the invention the front leg of the chair
frame is narrow, thus to pass easily through the space between the
door frame and seat. The footrest 36, when used, is also narrow
enough to pass through said space. The rear wheel assembly is
wider, thus to give the chair stability, both while in motion and
while resting on the automobile seat.
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