Wheel chair abstract
A raising wheel chair includes a raising frame with a lever parallelogram
to maintain a backrest upright both in sitting and standing position
of the user. A lever provides a movement of the backrest in such
a way that no movement between the backrest and the body of the
user takes place when a change from sitting to standing or lying
takes place.
Wheel chair claims
1. A raising wheel chair comprising: a wheelframe; and a raising
frame, said raising frame being connected to a frontal portion of
the wheel frame and comprising a seat support with a seat, a backrest
support with a backrest, and on each side of the raising frame a
lever parallelogram for maintaining the backrest vertical in a sitting
position as well as in a standing position of a user, said lever
parallelogram comprising a seat support bar and substantially parallel
thereto a parallelogram lever being pivotally connected with one
end to the frontal portion of the wheel frame and with another end
to the backrest support, wherein the backrest support comprises
on each side a column and a pipe section, said pipe section being
connected to the backrest and telescopically movable on said column,
and wherein a lever is pivotally connected to a rear position of
the seat support and to the pipe section for moving, both on a change
from the standing position and a change from a lying position to
a sitting position, or vice versa, the backrest away from a rear
end of the seat support, and toward the rear end of the seat support,
respectively.
2. The raising wheel chair as claimed in claim 1, wherein the lever
which pivotally connects the seat support with the pipe section
is selectively connectable at different positions at the seat support
or the pipe section, respectively.
3. The raising wheel chair as claimed in claim 1, wherein the parallelogram
lever can be extended or shortened by an electric motor.
4. The raising where chair as claimed in claim 3, wherein the motor
is an electric linear motor.
5. The raising wheel chair as claimed in claim 2, wherein the parallelogram
lever can be extended or shortened by an electric motor.
6. The raising where chair as claimed in claim 5, wherein the motor
is an electric linear motor.
Wheel chair description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. .sctn.119
to Swiss Application 1744/01 filed in Switzerland on 21 Sep. 2001,
and as a continuation application under 35 U.S.C. .sctn.120 to PCT/CH02/00518
filed as an International Application on 20 Sep. 2002 designating
the U.S., the entire contents of which are hereby incorporated by
reference in their entireties.
[0002] This application corresponds to commonly assigned U.S. patent
application entitled "RAISING WHEEL CHAIR," Ser. No. ______
(Attorney Docket No. 032553-041), which is filed on even date herewith
and which is hereby incorporated herein by reference in its entirety.
BACKGROUND
[0003] A raising wheel chair is disclosed comprising a wheel frame
and a raising frame, said raising frame being connected to the frontal
portion of the wheel frame and comprising a seat support with a
seat, a backrest support with a backrest and means for maintaining
the backrest vertical in the sitting position as well as in the
standing position of the user.
[0004] Different raising wheel chairs are known to be capable of
moving a person from the sitting position to a standing position.
The raising wheel chair according to U.S. Pat. No. 5,366,036 also
permits the movement of a person into a lying position. Most of
the prior art raising wheel chairs have the disadvantage that on
a stand-up motion or a sit-down motion a relative motion takes place
between the person and the surfaces of the chair making contact
with the body of the person. This gives the person an unpleasant
feeling and often a so-called shirt pulling effect takes place.
To avoid a motion between the backrest and the body of the person
in changing from the standing position to the sitting position,
and vice versa, U.S. Pat. No. 4,067,249 proposed to pivotally mount
the backrest on the rear part of the seat at a distance above the
sitting surface, so that the pivoting axis is located in the proximity
of the hip joint of the person. This, however, has the disadvantage
that in lying position the transfer of the person from the raising
chair into the bed is hindered by a protruding part of the chair.
[0005] In WO 82/01314 a raising chair is described comprising a
seat frame and a backrest frame. In the seat frame a seat is located.
The seat frame has on both sides a sidewall to which at the front
part and in the region above the hip joint of the user levers are
pivotally connected for moving the seat from the sitting position
to the standing position. The backrest which is movable in the backrest
frame is on both sides pivotally connected with a lever to the seat
frame, so that on standing up or sitting down the seat back is moved
and no substantial movement between the body of the user and the
backrest takes place. However, this raising chair has the disadvantage
that the seat frame has on both sides high side walls which prevent
a lateral transfer of the user. It is not possible to omit the side
walls, because three levers are connected thereto. It is further
of disadvantage that the backrest cannot be tilted downward to permit
a horizontal position of the user.
[0006] French patent application FR 2,589,341 discloses a wheel
chair where the backrest has on each side a rod which can be moved
in a tube. This permits an adjustment of the highs of the backrest
with respect to the user of the wheel chair. The tubes are connected
by a horizontal bar which can lifted or lowered by a lifting device,
but only the backrest will be lifted whereas Me seat remains stationary.
[0007] U.S. Pat. No. 5,366,036 describes a raising wheel chair
having arm rests capable of being tilted 90 degrees. Accordingly,
if the user is in a lying position, a transfer from the wheel chair
to the bed and vice versa is not hindered or made impossible by
some parts. In the U.S. Pat. No. 5,984,338 a raising wheel chair
is described which permits at least in the sitting position a lateral
transfer of the user. However, this raising wheel chair does not
permit a lying position and has further the disadvantage that a
shirt pulling effect can take place.
[0008] The disclosures of all of the foregoing patent documents
are hereby incorporated by reference in their entireties.
[0009] With reference to FIGS. 1 and 2 a prior art raising wheel
chair will be described. The prior art raising wheel chair comprises
a wheel frame 11 with a pair of front wheels 13 and a pair of rear
wheels 15, and a raising frame 21 comprising a seat 17 and a backrest
20. The raising wheel chair further comprises a footrest assembly
23 with a footrest 24. The wheel frame 11 comprises a tubular construction
with two side frames 25 which are connected by struts 27,28.
[0010] The raising frame 21 is also a tubular construction. The
backrest carrier 19 and the seat support bar 42 are pivotally connected
at 29. The backrest support 19 has a lever arm 31 which at 33 is
pivotally connected with the parallelogram lever 35. The parallelogram
lever 35 is in turn pivotally connected at 32 at the wheel frame
11. The seat support bar 32 is pivotally connected at 22 at the
wheel frame 11. By the lever parallelogram 34 formed in this way
it is assured that in each position of the chair the backrest 20
will remain in practically the same nearly vertical position. A
motor 37 serves for the raising motion from the position in FIG.
1 to the position of FIG. 2 or for the motion in opposite direction
for sitting down.
SUMMARY
[0011] A raising wheel chair is disclosed wherein, by moving the
backrest on a stand-up or sit-down motion, a relative motion between
the person and the backrest is avoided. When the person is in lying
position, a transfer from the raising wheel chair into the bed,
and vice versa, is not hindered by any protruding parts.
[0012] An advantageous embodiment of the invention provides that
the lever which is pivotally connecting the seat support with the
pipe section is selectively connectable at different positions at
the seat support or the pipe section, respectively. This permits
an adjustment to the requirements of users of different sizes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] An exemplary embodiment will be described with reference
to the drawing, wherein:
[0014] FIG. 1 shows a cross section through a prior art raising
wheel chair in sitting position;
[0015] FIG. 2 shows a cross section through the prior art wheel
chair of FIG. 1 in stand-up position;
[0016] FIG. 3 shows a perspective view of an exemplary electromotoric
raising wheel chair;
[0017] FIG. 4 shows an exemplary embodiment of the raising wheel
chair, but only showing the raising frame; and,
[0018] FIG. 5 shows an enlarged representation of a section from
FIG. 4, and FIG. 6 shows a section as in FIG. 5, but with the backrest
in lying position.
DETAILED DESCRIPTION
[0019] The present invention can be applied to all kinds of raising
wheel chairs. In FIG. 3 an electromotoric raising wheel chair is
shown. This raising wheel chair comprises a wheel frame 11 and a
raising frame 21 which can be vertically lifted and lowered by a
lifting device 30 as described in an application of the same day.
The raising frame is shown in more details in the FIGS. 4 to 6.
[0020] The raising frame 21 shown in FIGS. 4 to 6 includes features
similar to those of the raising frame of the raising wheel chair
described before with reference to the FIGS. 1 and 2. For the same
parts or parts with the same function the same reference numerals
are used as in the FIGS. 1 and 2. The raising frame 21 is substantially
a tubular construction with the seat support bars 42 of the seat
17 being pivotally connected at 22 on the wheel frame (not shown)
The seat back support 19 and the seat support bars 42 are pivotally
connected at 29. The seat back support 19 comprises a lever arm
31 being pivotally connected at 33 with the parallelogram lever
35. The parallelogram lever 35 is pivotally connected at 32 at the
wheel frame (not shown). The lever parallelogram 34 provided in
this way is responsible for keeping the backrest 20 (FIG. 3) in
practically vertical position both in the sitting position as in
the stand-up position.
[0021] To permit a person to lie down, means are provided to reduce
the length of the parallelogram lever 35. For this purpose a motor
40 may be used. By this motor 40 a force can be applied to the lever
arm 31 to tilt the backrest downward. On the embodiment shown the
seat carrier bar 42 and the parallelogram bar 35 are telescopic
to permit a change of the distance between the backrest 20 and the
front edge of the seat.
[0022] The seat back support 19 is provided on each side with a
column 41 and a tube section; 45 to permit a telescopic movement
of the seat back 20 on the columns 41. On both sides of the seat
support a lever 47 is pivotally connecting the seat support 18 with
the pipe section 45 in such a way that on a change from the sitting
position (FIGS. 4 and 5) to the lying position (FIG. 6), the seat
back 20 is moved towards the seat 17.
[0023] If FIG. 6 is turned counter clock wise by 90 degrees it
visualizes the standing position as in FIG. 2. The lever 47 can
selectively be connected e.g. at three different locations 48,48',48"
to vary the amount the seat back is moved.
[0024] To summarize the following can be noted:
[0025] The raising wheel chair comprises a raising frame 21 with
a lever parallelogram 34 to maintain the backrest 20 upright both
in slitting and standing position of the user. A lever 47 provides
a movement of the backrest in such a way that no movement between
the backrest 20 and the body of the user takes place when a change
from sitting to standing or lying takes place.
[0026] It will be appreciated by those skilled in the art that
the present invention can be embodied in other specific forms without
departing from the spirit or essential characteristics thereof.
The presently disclosed embodiments are therefore considered in
all respects to be illustrative and not restricted. The scope of
the invention is indicated by the appended claims rather than the
foregoing description and all changes that come within the meaning
and range and equivalence thereof are intended to be embraced therein. |