Wheelchair

Information

  • Patent Grant
  • 6352275
  • Patent Number
    6,352,275
  • Date Filed
    Thursday, July 20, 2000
    24 years ago
  • Date Issued
    Tuesday, March 5, 2002
    22 years ago
Abstract
A wheelchair includes two side frames (1L and 1R) consisting of respective lower frame parts (1′L and 1′R) and respective upper frame parts (1″L and 1″R). Each side frame has transverse, horizontal, tilt pivot axis (3) between its upper and lower parts. Forwards of each axis (3) is a tilt adjustment device (4) acting between the lower frame part and the upper frame part. Each device (4) may take the form of a gas spring, an electric motor or a screw device. The lower frame parts (1′L and 1′R) are linked by a pair of shear braces (5L and 5R) with a vertical pivot axis (6) in the center. The upper frame parts (1″L and 1″R) are linked by one or more pairs of transverse braces (8L and 8R) with a pivot axis (9) in the center. Seat plates are fixedly mounted at the top surfaces of the respective braces (8L and 8R). The seat plates can form the whole or part of the seat, or can be the basis for other seating elements, such as cushions and seat shells. A sling-form backrest is provided between the upper frame parts. When the tilt adjustment device (4) is operated, the upper frame parts and thus the seat and the backrest turn around the pivot axles (3) and give a desired tilt position. Independently of the tilt position, the wheelchair can be folded. This folding wheelchair has the advantage of having an occupant-operable tilt adjustment and is particularly advantageous in that the occupant can operate the tilt adjustment while seated in the wheelchair.
Description




BACKGROUND OF THE INVENTION




The invention concerns a foldable wheelchair.




The GB 15 61 694 describes a perambulator in which the child can be transported in both lying and seated position. The perambulator comprises a frame to which the wheels and the hand grips are attached, and a seat arrangement pivotally mounted on the frame and comprising a foldable seat covering. The tilt angle is adjusted manually and fixed by means of screws. The entire perambulator is foldable, whereby it is, however, not described how the components connecting the frame are designed to facilitate folding. This construction is not transferable to wheelchairs due to stability requirements. In addition, the seat frame must be placed in upright position or removed entirely before folding the perambulator.




The GB 20 29 33 40 describes a wheelchair comprising a motor drive and especially suited for severely disabled patients who can only move their fingers. The wheelchair is not foldable, so that no information on the details of the frame construction is given. The wheels and an upper frame with a seat which is tiltable around a horizontal axis are mounted on the lower frame. A mechanical, hydraulic or pneumatic adjustment mechanism is provided between the two frames for this purpose.




The GB 21 26 537 A describes a foldable wheelchair comprising two lateral frames to which the wheels are attached. Movable connection of the two frames is effected by means of two intersecting connection braces in the central area of the frame which can be moved scissor-like around a common folding axis in their intersection point. The tilt of the seat is not adjustable.




SUMMARY OF THE INVENTION




The joint axis of these transverse braces preferably extends in direction parallel with the seat and in longitudinal direction of the wheelchair.




The seat and backrest advantageously comprise a pair of seat panels also arranged foldably. The seat plates can form the whole or part of the seat or can act as the base for other seating elements, such as cushions and seat shells.




The pair of transverse pairs is preferably designed as a single piece and connected by a pressure hinge. The pressure hinge comprises at least one stop and at least one abutment, which abut on each other in unfolded state when the transverse braces lie in one plane. This defines the final position and prevents bending.




Since the seat plates are fastened on the upper side of the transverse braces, the transverse braces are also subject to pressure from above. In unfolded state the wheelchair is stabilised by the transverse braces and the seat plates, so that no additional arrest means are needed.




A further embodiment provides that the transverse braces possess at least one stop in the pivot area on the upper frame portion, which cooperates with at least one abutment of the upper frame portion when the wheelchair is in unfolded state. This also stabilises the unfolded state of the wheelchair. These stops and abutments can be provided alone or in combination with the pressure hinge.




According to a further embodiment, the juxtaposed brace pairs connecting the upper frame are replaced by individual elements. Tilt members are mounted preferably pivotally on the lower side of the seat plates on the upper frame portion.




These tilt members advantageously comprise at least one stop in the pivot area of the frame, whereby said stop cooperates with at least one abutment of the frame when the wheelchair is in unfolded state. occupant of the wheelchair is able to cause said tilt adjustment mechanism to operate to change the degree of tilt of the upper frame means relative to the lower frame means. The tilt adjustment mechanism can also be located backwards from said pivot means.











BRIEF DESCRIPTION OF THE DRAWING




In order that the invention may be clearly understood and readily carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:





FIG. 1

is a fragmentary top plan view of a wheelchair,





FIG. 2

is a perspective view of the wheelchair but with seat plates and a backrest removed for clarity of illustration,





FIGS. 3



a,b


a side plan view and a perspective view of the seat braces,





FIGS. 4



a,b


a side plan view and a perspective view of seat brace means according to another embodiment.











DETAILED DESCRIPTION OF THE INVENTION




Referring to the drawings, the wheelchair includes two side frames


1


(namely, a left-hand frame


1


L and a right-hand frame


1


R) consisting of respective lower frame parts


1


′ (namely, a left-hand lower frame part


1


′L and a right-hand lower frame part


1


′R) and respective upper frame parts


1


″ (namely, a left-hand upper frame part


1


″L and a right-hand upper frame part


1


″R). Each side frame


1


has a transverse, horizontal, tilt pivot axis


3


between its upper and lower parts


1


″ and


1


′. Forwards of each axis


3


is a tilt adjustment device


4


acting between the lower frame part


1


′ and the upper frame part


1


″. Each mechanism


4


may take the form of a gas spring or an electric motor (giving continuous adjustability) or of a screw or clamp device, such being manually remotely operable, for example by means of a press button, by the occupant of the wheelchair, or may be a screw device (giving continuous operability). The lower frame parts


1


′L and


1


′R are linked by a pair of shear braces


5


, consisting of a left-hand brace


5


L and a right-hand brace




The folding wheelchair described with reference to the drawings has the advantage of having an occupant-operable tilt adjustment and is particularly advantageous in that the occupant can operate the tilt adjustment while seated in the wheelchair.




In

FIGS. 3



a


and


3




b


the transverse braces


8


L,


8


R are shown in enlargement.

FIG. 3



a


shows the transverse brace pair in unfolded state;

FIG. 3



b


shows the same in folded state.




The transverse braces


8


L and


8


R respectively comprise a pivot hook


13


L and


13


R on their outer ends, whereby said hook pivotally attaches the transverse braces


8


L and


8


R on the upper frame portion


1


″L and


1


″R. The two seat plates


1


L and


11


R not shown in the Figure are mounted on the surfaces


14


L and


14


R of the transverse braces


8


L and


8


R. The transverse braces


8


L and


8


R are connected with each other by an integrated pressure hinge


15


comprising the pivot axis


9


. The pressure hinge


15


is formed in such manner that the position of the two transverse braces


8


L,


8


R shown in

FIG. 3



a


is stable. The pressure hinge


15


prevents bending of the transverse brace pair


8


L,


8


R even under pressure.




For this purpose, several stops and abutments are provided, as shown in

FIG. 3



b.


Each transverse brace


8


L and


8


R comprises stop surfaces


16




a,b


and


17




a,b


in the hinge area and corresponding abutment surfaces


18




a,b


and


19




a,b.


When the two transverse braces


8


L,


8


R are converted into extended, unfolded state as shown in

FIG. 3



a,


the stop surfaces


16




a,b


abut on the abutment surfaces


18




a,b.


The same applies to stop surfaces


17




a,b


which cooperate with the abutment surfaces


19




a,b.


In this way, a stable position of the transverse braces


8


L and


8


R is ensured without additional auxiliary means, whereby the whole wheelchair is simultaneously stabilized.





FIGS. 4



a


and


4




b


show a further embodiment. Whereas in

FIGS. 3



a


and


3




b


the pivot hooks


13


L and


13


R and the pressure hinge


15


are integral components of the transverse braces


8


L and


8


R, the embodiment shown in

FIGS. 4



a


and


4




b


consists




List of Reference Numerals






1


L left hand frame






1


R right hand frame






1


′L lower frame part






1


′R lower frame part






1


″L upper frame part






1


″R upper frame part






3


tilt pivot axis






4


tilt adjustment device






5


pair of shear braces






5


L left hand brace






5


R right hand brace






6


vertical pivot axis






7


vertical pivot axis






8


pair of transverse braces






8


L left hand transverse brace






8


R right hand transverse brace






9


pivot axis






10


pivot axis






11


L left hand seat plate






11


R right hand seat plate






12


sling-form backrest






13


L pivot hook






13


R pivot hook






14


L surface






14


R surface






15


pressure hinge






15


′pressure hinge






16




a,b


stop surface






17




a,b


stop surface



Claims
  • 1. A wheelchair comprising lower frame means and upper frame means tiltable backwards and forwards relative to said lower frame means, ground wheels mounted on said lower frame means, and seating and backrest means carried by said upper frame means, wherein said upper frame means includes at least one pair of transverse braces pivotally interconnected end-to-end and foldable around the pivotal interconnection and wherein said lower frame means include at least one pair of transverse braces pivotally interconnected end-to-end and foldable around their pivotal interconnection, so that said frame means are foldable inwards transversely of the wheelchair, substantially irrespective of the tilt position of said upper frame means, characterized in that the full length of said at least one pair of transverse braces of the lower frame means is greater than the width of the wheelchair in unfolded state defined by the at least one pair of transverse braces of the upper frame means or the seat plates included in the seating and backrest means.
  • 2. A wheelchair according to claim 1, wherein said seating and backrest means (11L, 11R, 12) include a flexible backrest (12).
  • 3. A wheelchair according to claim 1, wherein said pivotal interconnection of said pair of transverse braces of the upper frame means has a pivot axis being oriented in parallel with the seat surface.
  • 4. A wheelchair according to claim 3, wherein said pair of transverse braces of the upper frame means is provided as a single piece and connected by a pressure hinge.
  • 5. A wheelchair according to claim 4, wherein said transverse braces of the upper frame means comprise at least one stop in the pivot area and said stop cooperates with at least one abutment of the upper frame portion when the wheelchair is in unfolded state.
  • 6. A wheelchair according to claim 5, wherein said seating and backrest means include a pair of seat plates pivotally interconnected edge-to-edge and foldable around their pivotal interconnection.
  • 7. A wheelchair according to claim 6, wherein said seat plates are mounted on the transverse braces of the upper frame means.
  • 8. A wheelchair according to claim 1, wherein pivot members which pivotally rest on the upper frame portion are mounted on the lower side of the seat plates included in said seating and backrest means.
  • 9. A wheelchair according to claim 8, wherein said pivot members comprise a stop in the pivot area of the upper frame portion, which cooperates with an abutment of the frame portion when the wheelchair is in unfolded state.
  • 10. A wheelchair according to claim 8, wherein a pressure hinge which connects the two seat plates is mounted on the lower side of the seat plate.
  • 11. A wheelchair according to claim 10, wherein said pivotal interconnection of said pair of transverse braces of said lower frame means has a substantially vertical pivot axis.
  • 12. A wheelchair according to claim 11, wherein said pivot axes are disposed perpendicularly to each other if the upper frame means are not tilted.
  • 13. A wheelchair according to claim 12, wherein transverse, horizontal pivot means interconnect said upper frame means and said lower frame means, so that said upper frame means is tiltable around a horizontal axis relative to said lower frame means and a tilt adjustment mechanism is located forwards from said pivot means, an occupant of the wheelchair being able to cause said tilt adjustment mechanism to operate to change the degree of tilt of the upper frame means relative to the lower frame means.
Priority Claims (1)
Number Date Country Kind
9801215 Jan 1998 GB
PCT Information
Filing Document Filing Date Country Kind
PCT/EP99/00397 WO 00
Publishing Document Publishing Date Country Kind
WO99/37265 7/29/1999 WO A
US Referenced Citations (5)
Number Name Date Kind
4684149 Meyer Aug 1987 A
5244222 Benoit Sep 1993 A
5301970 Haskins Apr 1994 A
5727802 Garven, Jr. et al. Mar 1998 A
6135475 Brown et al. Oct 2000 A
Foreign Referenced Citations (8)
Number Date Country
92 06 467 Sep 1992 DE
0 163 139 Dec 1989 EP
1 561 594 Feb 1980 GB
2 029 334 Mar 1980 GB
2 126 537 Mar 1984 GB
8 701 951 Mar 1989 NL
8402647 Jul 1984 WO
9004957 May 1990 WO