Wheel chair abstract
The invention relates to an apparatus for lifting a wheel-chair
into and out from a vehicle, having a lifting arm which may be connected
to the wheel-chair. According to the invention the apparatus comprises
a substantially Z-shaped stand (4) having a lower support and mounting
plate (5) intended to be attached to the vehicle floor at the place
for the driver's seat by means of a number, suitably three, of bolts
(6), and a substantially vertical middle portion (7) an an upper
support plate (8) intended to be positioned on top of the back seat
of the vehicle, a lifting mechanism (25-45) and a swinging equipment
(36-45) for the lifting arm (3) whereby the lifting arm (3) and
the lifting mechanism (25-34) and the swinging equipment (36-45)
are carried by the upper support plate (8) of the stand (4). The
invention also relates to a collapsible wheel-chair especially adapted
for use together with the lifting apparatus.
Wheel chair claims
I claim:
1. Apparatus for lifting a wheel-chair into an out from a vehicle
comprising a lifting arm which may be connected to the wheel-chair,
a substantially Z-shaped stand having a lower support and mounting
plate for attachment to the vehicle floor at the place for the driver's
seat, substantially vertical middle portion and an upper support
plate for positioning on top of a back seat of the vehicle, and
means coupled to the upper support plate and to the lifting arm
for pivoting the lifting arm in a vertical and horizontal direction
to lift the wheel-chair into and out of the vehicle.
2. Apparatus according to claim 1, wherein the lifting arm is bent
at an angle and is rotatably mounted to a middle shaft, the rotational
movement of the outer part of the lifting arm being blocked by means
of a movement restriction stop, the middle shaft being pivotally
mounted in an outer part of a portion which is bent at an angle
and which extends in towards a pair of bifurcately combined foot
plate and the lifting arm being journalled for swinging movement
around an axis which extends between the foot plates.
3. Apparatus according to claim 1, wherein the pivoting means includes
a first means for pivoting the lifting arm in a vertical direction
by an electrical motor which through a transmission is connected
to a drive means and an output shaft having a position sensing rod
constructed with a limit switch the shaft being connected to a motion
transfer link which is pivotally mounted in a pair of foot plates,
a forwardly bent portion of the transfer link being provided with
a pressure roll which engages a portion of the lifting arm to raise
and lower arm when output shaft causes the transfer link to pivot
relative to the foot plates.
4. Apparatus according to claim 3 wherein the pivoting means further
includes a second means for pivoting the lifting arm in a horizontal
direction by an electrical motor which through a transmission and
a drive means operates a second output shaft for swinging the first
means and the lifting arm around a vertical pivot axle through a
connecting arm coupled to a link which is connected to the second
output shaft and which is pivotally mounted.
5. Apparatus according to claim 4 wherein a roll journalled to
a foot plate runs in a roller way provided on upper support plate,
to transmit the weight of the first means to the support plate through
roll during pivoting of the lifting arm in a horizontal direction.
6. Apparatus according to claim 5, wherein a latch mechanism blocks
a wheel-chair that is positioned as a driver's seat in the vehicle,
whereby the latch mechanism comprises a elongate, hook-like plate
which is pivotal between a lowered and a raised position, in that
this pivotal movement, through a motion transmitting link structure,
is caused by engagement of the lifting arm with an actuating lever
and its depression thereof by the swinging of the lifting arm into
its position furthermost in towards the middle of the vehicle.
7. In combination, a lifting apparatus for lifting a wheel-chair
into and out from a vehicle, comprising a lifting arm which may
be connected to the wheel chair, a substantially Z-shaped stand
having a lower support and mounting plate for attachment to the
vehicle floot at the lace for the driver's seat, a substantially
vertical middle portion and an upper support plate for positioning
on top of the back seat of the vehicle, and means coupled to the
upper support plate and to the lifting arm for pivoting the lifting
arm in a vertical and horizontal direction to lift the wheel chair
into and out of the vehicle and, a wheel-chair for conventional
use as a transport means indoors and outdoors and for use as a driver's
seat in a vehicle and adapted for use together with said lifting
apparatus, said wheel-chair comprising a seat mounted on a collapsible
chassis frame, a backrest attached to the seat, a number of lifting
straps for being coupled together with the lifting apparatus and
having at least one hand wheel for the propulsion of the wheel-chair
when used in a conventional manner, and a combined propulsion and
folding maneuvering means mounted in a cradle which is pivotally
connected to the wheel-chair seat and in which the rear wheels of
the wheel-chair are mounted for swinging up to a position behind
the wheel-chair backrest of the seat.
Wheel chair description
The present invention relates generally to a collapsible wheel-chair
and an apparatus for lifting the wheel-chair into and out from an
automobile, and more particularly the invention relates to such
an arrangement where the wheel-chair is collapsible from a condition
in which the user uses the wheel-chair as a conventional wheel-chair
for transportion indoors and outdoors, to a second condition where
the wheels of the wheel-chair are retracted and the wheel-chair
is used as a driver's seat in an automobile. In accordance with
the invention there is moreover provided an apparatus for lifting
the wheel-chair into and out from the automobile, which is being
done by means of a lifting arm to which the wheel-chair is attached
by means of lifting straps, whereupon the lifting arm on the one
hand can lift and lower respectively the wheel-chair with the user
sitting therein, and on the other hand can swing sideways between
a position outside the door opening of the automobile and a position
within the automobile.
Many different attempts have been made to provide arrangements
assisting disabled persons to get into and out from an automobile.
Different types of handicaps do naturally require different solutions,
and the present invention is especially, but not exclusively, directed
to assisting persons tied to a wheel-chair and having motion handicap
in their legs or hips, leg-amputated persons or the like.
By using a wheel-chair which on the one hand can be used by the
disabled by himself for moving about indoors and outdoors, and on
the other hand can be used as the actual driver's seat in the automobile
it becomes possible for the disabled himself, that is without the
need for an assistant, to move from his home to the car, to get
into the car, to drive the car to the desired location, to get out
of the car, to use the wheel-chair to move for instance inside and
between shops, service centers, public institutions and the like,
and subsequently to travel back home again in the reverse order.
Today this is impossible for many disabled since the existing systems
often rely upon the fact that the disabled is lifted out from his
wheel-chair and into the car, that the wheel-chair subsequently
has to be put into the luggage compartment, and even if the disabled
can drive his car by himself by means of different auxiliary devices
in the vehicle there is required an assistant for unloading the
wheel-chair from the luggage compartment and for lifting the disabled
from the driver's seat to the wheel-chair at the arrival. A typical
example of an arrangement where an assistant always must be at hand,
is illustrated and described in U.S. Pat. No. 4,170,368, where indeed
the same chair is used as seat for the wheel-chair and as driver'
s seat in the car, but where the seat itself is disassembled from
the frame of the wheel-chair and is lifted into the car whereupon
an assistant must take care of the frame in order to place it in
the luggage compartment, and at the arrival an assistant is required
once more for lifting out the frame and for placing the frame in
a correct position for assembly with the seat. This known structure
is also an example of another typical arrangement, namely where
the docking takes place from behind, that is the wheel-chair must
be backed in towards a lifting means, be connected to this lifting
means and subsequently be lifted backwards into the car. Besides
the difficulty in handling into the car. Besides the difficulty
in handling a docking operation with the back facing the equipment
it will be understood that the swinging movement will be backwards,
that is the person will be lifted into the car backwards, which
means difficulties regarding the height adjustment so that the back
of the person's head does not strike against the upper edge of the
door opening, and will subsequently be swung forwardly towards the
steering wheel which in this case often constitutes an obstacle
since it is positioned in the actual path of movement. Other examples
of chairs that are engaged and lifted from behind are disclosed
in for instance U.S. Pat. Nos. 3,882,949 and 4,155,587 and in Swedish
patent application No. 7906894-6.
Another type of arrangement for lifting a wheel-chair into and
out from respectively an automobile comprises a swinging arm that
is journalle forwardly inside the door opening of the car, and the
other free end of which is intended to be connected to the wheel-chair
in a docking operation, whereupon the arm lifts and swings the wheel-chair
into the car. This type of arrangement is illustrated and disclosed
for instance in European patent application No. 81301028.7 (publication
No. 36293). By arrangements of this kind the steering wheel will
likewise prevent a quick and easy lifting of the wheel-chair and
the user into and out from the car. Often the car must be modified
in such a way that the steering wheel can be brought aside and besides
the fact that this is obviously a very expensive and complicated
method it does also give rise to certain risks during the use thereof
if for instance the movable steering wheel can be disengaged. Moreover
the whole arrangement will be positioned in front of the wheel-chair
when the car is driven which in itself can be a hindrance.
Still another type of wheel-chair and an apparatus for lifting
the same into and out from an automobile shall be discussed herein,
namely the one illustrated and described in CH-patent specification
No. 472.213. Similarly to the present invention this known structure
uses the wheel-chair both as such and as driver's seat in the automobile.
However, the large, rear wheels of the wheel-chair must be disassembled
in connection with the conversion of the wheel-chair to a driver's
seat which is to be lifted into the car. This is impossible for
the user himself to do without any aid from an assistant. The apparatus
for lifting the wheel-chair into and out from the car consists of
a lifting arm which is slidably mounted on a transversal guide beam
extending across the full width of the car. This guide beam can
in turn be raised and lowered respectively by manually pumping a
hydraulic lifting device, and hereby the lifting arm can be raised
and lowered. It is indicated that the lifting arm will be connected
to the wheel-chair which probably takes place in a docking operation
which most likely means that the arm in a not shown manner is coupled
together with the actual wheel-chair.
The above detailed statement of the previously known attempts to
provide a wheel-chair and an operation for lifting the wheel-chair
into and out from an automobile has been made in order to point
out some of the many previously known attempts to solve the problems
that exist in this connection. In accordance with the invention
the wheel-chair and an apparatus for lifting the wheel-chair into
and out from an automobile are provided by which the above indicated
problems have been solved.
The object of the invention is thus to provide a wheel-chair that
can be used partly as a means of transportation in itself and partly
as a driver's seat in an automobile, and the object of the invention
is also to provide an apparatus for lifting the wheel-chair into
and out from an automobile.
Another object of the invention is to provide an arrangement where
the user himself without requiring any assistant can move in the
wheel-chair from his home and to the car, by himself can perform
all the necessary connecting and maneuvering operations for lifting
the wheel-chair (with the user sitting therein) into the car, can
drive the car to the intended place, by himself can perform the
necessary maneuvers and connecting operations for lifting the wheel-chair
out from the car and subsequently can use the wheel-chair to move
around. The fact that the disabled user himself without the need
for any assistant can move from his home and to a desired place
increases his freedom or independence which is very essential for
the psychical well-being.
Another object of the invention is to provide an apparatus for
lifting a wheel-chair into and out from an automobile, which apparatus
can be mounted in any automobile having a suitably large door opening
without any other modifications to the automobile than the disassembly
of its regular driver's seat, and the installing of the lifting
apparatus according to the invention in its place by means of simple
bolt connections.
Another object of the invention is to provide a lifting apparatus
for lifting a wheel-chair into and out from a car, which lifting
apparatus does not block more than one seat (apart from the driver's
seat), namely the seat behind the driver's seat. Hereby it is possible,
when desired, to let at least two passengers ride in the car.
Still another object of the invention is to provide a lifting apparatus
for lifting a wheel-chair into and out from an automobile, where
the requirement for muscular strength on the part f the user is
very small, at the same time as the user himself without the need
for any assistant, can operate the control means that are provided
for operating the lifting apparatus sideways and vertically.
Other objects of the invention that are not mentioned here will
be understood by a man skilled in the art to the extent that they
are not clear from the following description, the enclosed patent
claims and the accompanying drawings.
The features especially characterizing the invention are clear
from the enclosed patent claims.
The invention will be more closely described below with reference
to the embodiment illustrated in the enclosed drawings where:
FIG. 1 is a schematic perspective view illustrating the apparatus
for lifting a wheel-chair into and out from a car, where the lifting
arm is shown swung out through the door opening of the car to a
position where it is to be connected to the lifting straps of the
wheel-chair,
FIG. 2 illustrates the lifting apparatus according to the invention
seen from above with the lifting arm shown in an inwardly swung
position in which the disengagement of the lifting straps of the
wheel-chair is to take place,
FIG. 3a is a side view illustrating the lifting apparatus according
to the invention seen from the side of the door opening and where
especially the lifting mechanism is illustrated,
FIG. 3b is a schematic view similar to FIG. 3a with one of the
foot plates removed and with one of the transfer link plates partly
cut away for reasons of clarity.
FIG. 4 is a schematic perspective view illustrating a wheel-chair
according to the invention,
FIG. 5 is an exploded view illustrating the propulsion and folding
arrangement for the wheel-chair according to FIG. 4,
FIG. 6a is a side view illustrating the cradle of the wheel-chair
frame in an extended position,
FIG. 6b is a cross-section along the line B--B in FIG. 6a, and
FIG. 6c is a schematic illustration of the folding of the cradle.
The lifting apparatus according to the invention is in the drawings
illustrated mounted in an automobile 1 through the door opening
2 of which the lifting arm 3 of the lifting apparatus can be swung
out. A substantially Z-shaped stand 4 comprises a lower support
and mounting plate 5, which by means of bolts 6 is bolted to the
floor of the car at the place for the driver's seat. The stand furthermore
comprises a substantially vertical middle portion 7 and an upper
support plate 8 which is positioned on top of the seat cushion 9
of the back seat or just above the same. By the installation of
the apparatus according to the invention neither the seat cushion
9 of the back seat nor its backrest 10 are worked upon, and no limitation
is being put on the space by the front passenger's seat or the passenger's
seat or seats behind the front passenger's seat. The only modification
that is necessary to perform to the vehicle in connection with the
installation is that the regular driver's seat is disassembled,
whereafter the lifting apparatus is lifted into the car and is mounted
to the vehicle floor by means of the illustrated bottom bolts 6.
The lifting apparatus which is supported by the stand 4 comprises
a lifting arm 3 by the outer free end of which a catching loop 11
is provided. The outer part 12 of the lifting arm 3 is bent at an
angle at 12a, and at 13 it is rotatably mounted to a middle shaft
14. A movement restriction stop 15 blocks the turning movement of
the outer part 12 of the lifting arm. The middle shaft 14 is hinged
at 16 to a connecting piece 17a of a portion 17 that is bent at
an angle at 17b and that extends in towards a supporting foot 18
in the shape of a pair of bifurcately combined foot plates 19, 20.
The entire lifting arm 3 is journalled for a pivotal movement around
an axis 21.
The bifurcately mounted foot plates 19 and 20 are at their rear
ends provided with an upwardly extended portion 22 to which a lifting
mechanism 23 is mounted at 24. The lifting mechanism comprises an
electrical motor 25, the output shaft of which is connected to a
driving means 26 through a transmission. An output shaft 27 having
a position sensing rod 28 provided with a limit switch is at 29
connected to a motion transfer link 30 in the shape of two angularly
bent plates extending parallel to each other at a distance from
each other and pivotally journalled at 31, which link at the forwardly
bent portion 32 is provided with a pressure roll 34 which is mounted
at 33 and which from below contacts the rear portion 17 of the lifting
arm extending between the two transfer link plates.
As schematically illustrated in FIG. 3b portion 17 of the lifting
arm 3 is at its innermost end pivotally mounted at 21 and extends
outwardly between the transfer link plates. As is also clear from
FIG. 3b portion 17 rests on pressure roll 34 which is coupled to
the transfer link adjacent the outer end of forwardly bent portion
32. Since the transfer link plates are pivotally mounted to the
foot plates 19 and 20 respectively at their inner side walls it
will be realised that when transfer link 30, 32 as discussed below,
is pivoted around axis 31 from the position illustrated with dashed
lines in FIG. 3b to the position illustrated with full lines therein,
the entire lifting arm 3 will simultaneously be pivoted around axis
21 due to the contact between pressure roll 34 and portion 17 of
the lifting arm.
In the position illustrated in FIG. 1 and in the lifting arm 3
is in its lowermost position. When the electrical motor 25 is activated,
which is carried out by means of an operating lever which is brought
to a position "upwards", and the electrical motor 25 starts,
the driving means 26 pulls in the output shaft 27, the link arrangement
30, 32 is swung around the axis 31 and, as indicated above, through
its contact with the inner or rear portion 17 of the lifting arm,
the pressure roll 34 lifts the entire lifting arm 3 upwards around
its fixed pivot 21. When the lifting arm 3 is to be lowered the
operating lever is moved to the position "downwardly",
the electrical motor 25 starts and rotates in the reverse direction,
the output shaft 27 is extended by means of the driving means 26,
the link 30, 32 is swung forwardly/downwardly around the axis 31,
and the lifting arm 3 can be swung downwardly around its fixed pivot
21. In this connection it should be noted that even if the lifting
arm 3 will move downwards due to its own gravity and possibly additional
load, there is also a forced operation of the lifting arm 3 in a
downward direction due to the fact that a shoulder 35 (FIG. 3) is
attached to the link 30 in such a way that when the inner or rear
portion 17 of the lifting arm is swung downwardly by means of the
link 30 this shoulder 35 will contact the upper side of the arm
17 and press it downwardly. This is important in another aspect
since, as will be explained more closely below, a catch mechanism
for locking the wheel-chair in position on the car floor is activated
by means of the lifting arm, when this in its position where it
is completely swung in, is forced to swing downwardly and thereby
to act upon a catch and maintain this in a locking position.
The lifting arm 3 can be swung sideways by means of swinging equipment.
As is best illustrated in FIG. 2 an electrical motor 36 for the
swinging movement is pivotally attached to the frame at a mounting
position 37. The motor 36 has a conventional gear change and a drive
means 38 which forces an output shaft 39 to move outwardly or inwardly
respectively depending upon the direction of rotation of the electrical
motor. The foot 18-22 of the lifting equipment is pivotally mounted
around a vertical pivot axle 40 (compare with FIG. 3). The output
shaft 39 is connected to a pivotally mounted link 41 at 42, and
when the output shaft 39 by the drive means 38 is moved outwardly
it brings the link 41 to swing in counter-clockwise direction (as
seen in FIG. 2) about vertical pivot axle 40, and by means of a
connecting arm 43 that is attached to the frame of the lifting equipment
the lifting arm 3 and its supporting foot and drive means are swung
in a counter-clockwise direction as seen in FIG. 2. During this
swinging movement the weight of the equipment is transmitted to
the support plate 8 through a roll 44 mounted in a bracket 44A at
the outer end of the supporting foot. Roll 44 runs in a roller way
45 provided on top of the upper support plate 8 and transmits the
vertical forces to said roller way. Thus, whenever supporting foot
18 is swung about the vertical pivot axis 40, the roll 44 runs in
the roller way 45 so that the vertical forces applied to the lifting
arm 3 are continuously transmitted to the upper support plate 8.
The electrical motor 36 for bringing about the swinging movement
of the lifting arrangement is actuated by means of an operating
lever which in a position "inwardly" actuates the electrical
motor to rotate in the direction that brings about the inward swinging
of the entire lifting apparatus towards the center of the car, and
an actuation of the operating lever to its position "outwardly"
brings about an extension of the output shaft 27 and a swinging
of the lifting arm 3 in a counterclockwise direction as seen in
FIG. 2, in such a way that the lifting arm is swung outwardly towards
and past the door opening 2 as illustrated in FIG. 1.
The electrical equipment for the different electrical functions
is contained in a box 46.
FIG. 1 illustrates a catch mechanism 47 for locking the wheel-chair
in the correct position on the floor when it is to be used as driver's
seat in the car. The catch or lock mechanism 47 consists of an elongate,
hook-shaped plate which is pivotal around a longitudinal axis between
an opened or unlocked position and a closed locking or catching
position. This pivotal movement is brought about by means of a motion
transmitting link structure, schematically depicted in FIG. 1, positioned
under the Z-shaped stand plate 4 and extends up to an actuating
lever 48. The actuating lever 48 is spring-biased in an upward direction,
that is to the position in which the catch 47 is unlocked or released.
When the wheel-chair has been placed in the intended position and
is to be locked there by means of the catch 47, the lifting arm
3 is swung to its position where it is placed as far as possible
in towards the middle of the car, which position is determined by
means of a limit switch, where the power supply to the electrical
motor by force is cut-off. Subsequently the lifting equipment is
lowered by means of the raising and lowering mechanism, whereby
the rear portion 17 of the lifting arm 3 contacts the catch actuating
mechanism 48 and depresses the same and whereby the motion transmitting
link mechanism (not shown in the drawings) converts this depressing
movement to a pivotal movement for the catch mechanism 47 which
then locks the wheel-chair to the vehicle floor.
In this position when the wheel-chair is used as driver's seat
the lifting arm 3 is folded to a retracted storage position in which
the arm is locked by means of a latch mechanism 49.
With reference to FIGS. 4 to 6 a wheel-chair according to the invention
will now be described, which wheel-chair is specifically adapted
for use together with the above described lifting apparatus.
With reference to FIG. 4 the wheel-chair basically consists of
a cushion seat 50 with a backrest 51 the inclination of which can
be adjusted by means of an adjusting means 52 which does not constitute
any part of the invention and which accordingly will not be described
in detail. The seat 50 is fixed to a frame 53 which is provided
with a bracket (not shown in FIG. 4) which is engaged by the latch
or locking mechanism 47 of the lifting apparatus when the wheel-chair
is locked to the vehicle floor. Due to the fact that the catching
point for locking the wheel-chair is positioned in the seat frame
and not, as has been common before, in the chassis frame said chassis
frame does not have to be dimensioned to stand the loads that are
stipulated in traffic safety regulations (corresponding to 12 g
for the driver's seat in an automobile). The seat framme 53 is moreover
provided with guide rolls 54 which run on the mounting plate 5 (FIG.
1) anchored to the vehicle when the wheel-chair is installed in
the vehicle. Finally, the seat is also provided with a pair of arm
rests 55 in connection with each one of which one end of a pair
of crosslaid lifting straps 56 are releasably attached. The other
ends of the lifting straps 56 are (as will be described more closely
below) attached to a pair of latches 83 in the chassis frame for
actuating the same. The lifting straps 56 are at the point where
they cross each other connected by means of a lifting hook 57 which
will be connected to the lifting apparatus by the maneuvering of
the wheel-chair into and out from the vehicle.
The chassis frame 58 basically consists of two portions, namely
a cradle 59 which is pivotally connected to the frame 53 at 80 (FIG.
6a) and in which the rear drive wheels 60 and a propulsion and folding
maneuvering means 61 are mounted, and a suspension 62 which is pivotally
connected to the frame 53 as well as to the cradle 59 and in which
the small front wheels 63 and a conventional foot plate 64 are mounted.
The suspension 62 is also connected to a gas cylinder (not shown
in the Figures) which controls the suspension 62 and through this
indirectly the cradle 59 for folding the wheel-chair prior to its
lifting into the vehicle.
With reference to FIGS. 5 and 6a-c the propulsion and folding maneuvering
means 61 will now be described more in detail. Actually one propulsion
and folding maneuvering means is provided by each side of the wheel-chair
but since these are identical only one of them will be described.
Thus, the arrangement comprises a hand wheel 65 which is provided
with a sprocket 66. When the disabled uses the wheel-chair to move
around he actuates the hand wheel 65 whereby this through a chain
drive 67 drives the rear wheel 60 which likewise is provided with
a sprocket 68. Through this arrangement it is easy to change the
transmission ratio of the propulsion by varying the size of sprockets,
and this is of a great practical importance since the propulsion
hereby can be adapted for instance to the weight or the strengths
in the arms of the user.
The hand wheel 65 is by means of a pin 69 journalled in an inner
ball-bearing 70 the outer race of which in turn is fixed in an outer
ball-bearing 71 the outer race 71a of which is fixed to the cradle
59 (indicated by means of dashed lines in FIG. 5). The inner race
of the outer ball-bearing 71 is fixed to a crank arm 72 and the
function thereof will be described more closely below with reference
to FIGS. 6a-c.
In order to cover the chain drive 67 a chain guard 73 is provided
which is fastened partly at the rear wheel and partly at the outer
end of the pin 69. In connection with the mounting of the chain
guard 73 at the pin 69 the chain guard is provided with through
holes 74 which are arranged opposite each other and in which pegs
75 are slidably mounted. Furthermore, a bushing 76 is displaceably
arranged on the pin 69 between the chain guard 73 and the hand wheel
65. Finally, an operating lever 77 is pivotally mounted at the outer
end of the pin 69 by means of a bolt which is screwed into an internally
threaded, axial bore in the pin 69. The operating lever 77 is pivotal
between a propulsion position and a braking and folding position
respectively and is thereby designed in such a way that in the area
of its mounting on the fastening bolt it discloses a curve shape
in such a way that it in its propulsion position does not actuate
the pegs 75 which in the assembled condition protrude a short distance
from the chain guard 73. However, when the operating lever 77 is
swung to its braking and folding position its curved portion will
engage the pegs 75 and press these inwardly to contact the bushing
76 which in turn is pressed against the hand wheel 65. The hand
wheel 65 which in turn is slidably and rotatably mounted on the
pin 69 is thereby pressed inwardly into contact with the inner ring
of the outer ball-bearing 71 through a friction lining 78 provided
therebetween. As will be described more closely below with reference
to FIG. 6 the crank arm 72 is, in the condition for propulsion of
the wheel-chair, blocked against rotation around the ball-bearing
71 and in this condition the operating lever 77 is thus working
as a brake due to the fact that the hand wheel 65 through the friction
lining 78 is pressed against the bearing of the blocked crank arm
72.
As has been indicated above the propulsion and folding means 61
has a double-function since it is also used for folding the wheel-chair
when the wheel-chair is to be lifted into a vehicle by means of
the above described lifting apparatus in order to function as a
driver's seat therein. This function shall now be described more
closely with reference to FIG. 6a in which the cradle 59 is illustrated
in greater detail, but the hand wheel and the chain guard have been
deleted for reasons of clarity. The cradle 59 consists of a steel
tube frame which is articulately connected to the seat frame 53
at 80 and which also communicated with the frame 53 due to the fact
that the crank arm 72 by means of a roll 79 (see FIG. 5 and especially
FIG. 6b), which is provided with a groove, is guided in a cut-out
portion 81 in a guide plate 82 which is attached to the seat frame
53 partly directly adjacent the seat 50 and partly at a point near
the joint 80. In the normal condition the free end of the crank
arm 72 is locked in the upper end of the cut-out portion 81 by means
of the above-mentioned latch 83 which by means of spring 90 is biased
to this locking position illustrated with dashed lines on FIGS.
6a and 6b.
When the wheel-chair has been moved up to the vehicle, in order
to be lifted into the vehicle, the catching loop 11 of the lifting
apparatus is hitched to the lifting hook 57 which keeps the crosslaid
lifting straps 56 in their place as has been described above. When
the lifting arm 3 of the lifting apparatus subsequently is maneuvered
upwardly in such a way that the weight of the wheel-chair and the
user loads the lifting straps 56, the latch 83 is swung away against
the biasing of spring 90 in order to release the crank arm 72 due
to the fact that, as has been mentioned above, the front endsof
the lifting straps 56 are mounted in the latch 83 (FIG. 6a) which
in turn is mounted for pivotal movement around the joint 84. In
this connection it should also be pointed out that although only
one guide plate 82 and latch 83 are visible on the drawings, it
is preferable to use one such combination by each side of the wheel-chair,
that is one for each propulsion and folding means. Thus, when the
wheel-chair is lifted up from the ground by means of the lifting
arm and the latch 83 has been released the operating lever 77 is
brought to the position which by normal propulsion of the wheel-chair
brings about the braking of the wheel-chair. As mentioned above
this causes the hand wheel to be pressed against the bearing 71
of the crank arm 72 by means of the pegs 75 and the bushing 76 and
through the friction lining 78. The blocking of the crank arm 72
is now released due to the fact that the latch 83 has been swung
away to permit roll 79 to move in cut-out portion 81 of the plate
82. Maneuvering of the hand wheel 65 will however, through the friction
engagement between the hand wheel, the friction lining 78 and the
bearing 71 of the crank arm 72, rotate the crank arm 72 in the same
direction. Since the free end of the crank arm 72 is guided in the
cut-out portion 81 it will, by a continued maneuvering of the hand-wheel
65, initially move downwards in the cut-out portion at the same
time as the entire cradle is swung upwardly around the joint 80,
and will then, when it has rotated over approximately 90.degree.,
once more move upwardly in the cut-out portion 81 until it has been
swung to the position illustrated with dashed lines when the cradle
is completely swung up towards the seat, in which position the free
end of the crank arm once more is positioned at the upper end of
the cut-out portion. Through the action of the above-mentioned,
not shown, gas cylinder the wheel-chair is maintained in this folded
condition during the lifting thereof into the vehicle, and when
the wheel-chair is once more lowered down and placed in its position
in the vehicle, and the lifting straps 56 are thus once more relieved,
the latch 83 will through its spring-biasing means 90 be returned
to the position where it blocks the crank arm 72 and thus locks
the wheel-chair in the folded condition.
With specific reference to FIGS. 6a-c the releasing and blocking
of the crank arm by means of the latch 83 and the pivoting of the
cradle will now be explained in detail. As mentioned above the latch
83 is normally biased to its position illustrated with dashed lines
in FIGS. 6a and 6b by means of biasng spring 90. As is especially
clear from FIG. 6b latch 83 is positioned adjacent the inner side
of the guide plate 82 and is pivoted in a plane parallel to the
guide plate 82. Thus, it will be understood that the latch 83 in
its normal position (illustrated with dashed lines in FIGS. 6a and
6b) bears against roll 79 at the outer end of the crank arm 72 and
blocks movement of the latter in the cut-out portion 81 in the guide
plate 82. As discussed above and as illustrated in FIG. 6a the lifting
strap 56 is attached to the latch 83 at 83a, and this means that
when the wheel chair is lifted by means of the lifting arm coupled
to the hook 57, the load is transmitted through strap 56 to latch
83 so that latch 83 is swung clockwise in FIG. 6a against the action
of biasing spring 90. This released position is illustrated in full
lines in FIGS. 6a and 6b. Thus, it will now be understood that in
this position for the latch 83 the roll 79 at the outer end of the
crank arm 72 is free to move in the cut-out portion 81 of the guide
plate 82.
As discussed above a maneuvering of operating lever 77 to its braking
and folding position causes the hand wheel to be operatively connected
to the crank arm 72 through the friction lining 78, and this means
than when the operating lever 77 is brought to said folding position
and the wheel chair has been lifted off the ground by means of the
lifting arm, a counter-clockwise rotation of the hand wheel (as
seen in FIGS. 5 and 6a) will be transmitted to crank arm 72 through
said friction lining. However, since roll 79 is restricted to move
in the cut-out portion 81 such a counter-clockwise rotation of the
crank arm 72 is still blocked due to the fact that the cut-out portion
has an extension other than that which would permit rotation of
the crank arm in the outer race 71a of the outer ball bearing 71,
as discussed above. This means that a further operation of the hand
wheel 65 will cause a reaction force to be applied to said outer
race 71a which is connected to the cradle 59. As a result of this
reaction force the operation of the hand wheel will cause the cradle
to pivot about the joint 80 from position I in FIG. 6c and towards
position II therein. Since the distance between joint 80 and the
centre of outer race 71a is fixed during this pivotal movement roll
79 will move to the left in FIG. 6c in the cut-out portion during
the simultaneous pivotal movement of cradle 59 and counter-clockwise
rotation of the crank arm 72 to position II in FIG. 6c. Likewise
the roll 79 will return to the upper end of cut-out portion 81 when
this pivotal and rotational movement continues toward position III
in FIG. 6c, so that when the folding maneuver is completed roll
79 is once more positioned at the uppermost end of the cut-out portion
81 and may once more be blocked in that position when the latch
83 is unloaded and is returned to its blocking position by means
of biasing spring 90. When unfolding the wheel-chair the hand wheel
is rotated clockwise and the operation is exactly the same as disclosed
above but only reversed.
The lifting out of the wheel-chair from the vehicle is accomplished
in the corresponding way.
By means of the described structure it is on the one hand achieved
that the wheel-chair is very simple and uncomplicated to use due
to the combined propulsion and folding maneuvering mens and on the
other hand that the wheel-chair due to the special folding mechanism
is very safe even if it should be maneuvered in an incorrect manner.
The last mentioned fact is achieved by means of the latches 83,
which are operatively connected to the lifting straps 56, due to
the fact that these latches very effectively prevent any folding
of the wheel-chair before it is hitched to the lifting apparatus
and raised a distance by means thereof. Thus, there is no danger
of the wheel-chair being unintentionally folded when it is being
used as a common wheel-chair. Moreover there is no danger of the
disabled himself inadvertently releasing the wheel-chair from the
lifting apparatus before the latch in the correct manner has been
caused to block the movement of the crank arm. Should the user by
mistake not have unfolded the wheel-chair completely in connection
with its lifting-out from the vehicle he will notice this immediately
when the wheel-chair is lowered down onto the ground, and thus while
it is still hanging in the lifting arm, since it in that situation
only very slowly would collapse during the downward movement of
the lifting arm. If this situation should occur it is thus only
necessary to manuever the lifting arm upwards again and to unfold
the wheel-chair in the correct manner whereby the latches are activated
at the same instance as the wheel-chair is put down onto the ground
and the lifting straps 56 are relieved.
Through the described design and swinging-up of the cradle a further
advantage is achieved, namely that in the unfolded condition for
the wheel-chair, when this is used for conventional transportation,
the backrest is relatively upright, while the backrest in the folded
condition of the wheel-chair is inclined backwards in a suitable
position for driving a car. The inclination can moreover be adjusted
by means of the mentioned adjustment means 52.
As has been mentioned above the chassis frame of the wheel-chair
also comprises a suspehsion 62 for the front wheels 63 but this
suspension does not constitute any essential part of the invention
but is substantially based upon conventional technique and will
thus not be described in detail neither in the Figurs nor in the
description. It should only be mentioned that due to the fact that
this suspension 62 is pivoted on the one hand in the seat frame
53 and on the other hand in the cradle 59 it is effectively locked
in a folded and unfolded condition respectively. When the wheel-chair
is to be folded and the cradle in the above described manner has
been released and swung upwardly by means of the hand wheel the
suspension 62 is also released and it is thereby folded or retracted
in step with the swinging-up of the cradle operated by the not shown
gas cylinder. Furthermore, the front wheels 63 and the suspension
are provided with co-operating guide surfaces whereby the front
wheels, when the suspension is folded, simultaneously are swung
inwardly towards the middle of the wheel-chair in such a way that
they when the wheel-chair is completely collapsed have assumed a
horizontal position immediately below the seat 50. Finally, the
foot plate 64 is also provided with an adjusting means 85 for adjusting
its height and by means of this adjusting means it is at the same
time guaranteed that the foot plate 64, independently of its adjusted
height in the unfolded condition for the wheel-chair, always will
be positioned at the same level of height in relation to the seat
when the wheel-chair is collapsed.
Even if the invention has been described and illustrated herein
with reference to a suitable embodiment thereof it should be obvious
for a man skilled in the art that this embodiment is not intended
to be restricting, but only explanatory and thus modifications and
alterations can be carried out within the scope of the invention
as this is indicated in the enclosed patent claims. |