EP3243492B1 - Wheelchair with standing assistance having a downwards-backwards standing-assistance path of the footrest - Google Patents

Description

The present invention relates to wheelchairs used by disabled and disabled persons designed to be made verticalizers to temporarily maintain the user in a substantially upright position.

The state of the art has proposed many so-called verticalization wheelchair solutions generally involving an articulated structure comprising a backrest, a seat and a footrest. Such a structure is mounted articulated generally by the seat on a horizontal front axis and perpendicular to the vertical plane of symmetry of the frame. A motor member is interposed between the frame and the articulated structure to allow the raising or lowering of the latter and able to occupy a folded said seat position and a vertical said unfolded position. The motor unit can be indifferently manual or electric control.

This prior art can be illustrated in particular by the French patent 69-35042 , the German patent application 2625045 or the French patent 82-11713 .

The structural proposals that have been formulated by the prior art generally rely on the articulation of the articulated structure on a horizontal front axis and perpendicular to the vertical plane of symmetry of the frame and bearing on the latter. Such an architecture has the effect in the verticalization function, to transfer the articulated structure and the user verticalized to the front part of the chair with the consequence of an increase in the load on the front wheels and a reduction in those of the rear wheels.

Such a consequence introduces a factor of instability, since the support polygon is not loaded in a homogeneous distribution. This is the reason why additional points of support are generally provided to stabilize the chair in the state of verticalization of the articulated structure. Such additional support points are constituted by rollers or pads mounted in the extension of the footrest, so as to bear on the ground in the verticalized state of the articulated structure. If such a solution makes it possible to confer a factor of stability and safety for the users, on the other hand, it makes difficult the mobility of the wheelchairs in the verticalized state of the articulated structure.

The document WO 95/25497 describes a standing wheelchair comprising a frame provided with wheels defining a support polygon and supporting an articulated structure. This articulated structure comprises a first deformable quadrilateral supporting a seat and having two lower ends mounted on the frame. This articulated structure also comprises a second deformable quadrilateral supporting the footrest and an elevation control system lowering the articulated structure. This control system comprises a motor member interposed between the frame and the articulated structure and adapted to control the displacement of deformable quadrilaterals between a folded stable state and an unfolded stable state corresponding to the vertical position.

The characteristics of the deformable quadrilaterals are chosen by construction so that, after the movement of the drive member, the seat and the backrest are substantially aligned in a slight inclination while the footrest is retrotected by the inclination inside the support polygon defined by the wheels of the chair. Positioning the user verticalized within the support polygon gives the wheelchair brought into such a position, a stable state allowing movement via the wheels.

During the transition from the folded stable state (sitting position of the user) to the unfolded stable state (vertical position), the articulated structure knows a retrodelplacement with an upward movement of the footrest. This retroverticalization operation leads to raising the user, which requires developing a significant mechanical effort to lift the user and simultaneously perform anteroposterior movement. It follows that the center of gravity of the user rises during the verticalization operation does not give the user a good impression of stability in a vertical position. In the same sense, it proves difficult to verticalize large users who are in a position too high.

The present invention aims to overcome the drawbacks of the prior art by providing a wheelchair designed to cause, during verticalization, a retrodelocation of the articulated structure to center verticalized load relative to the support polygon of the chair, while conferring the user stability and security in vertical position of the chair.

• un premier quadrilatère déformable supportant une assise et présentant deux extrémités inférieures montées sur le châssis ;
• un deuxième quadrilatère déformable supportant un repose-pieds ;
• et un système de commande en élévation-abaissement de structure articulée comportant un organe moteur interposé entre le châssis et la structure articulée et apte à commander le déplacement des quadrilatères déformables entre un état stable replié correspondant à une position dite assise de la structure et un état stable déplié correspondant à une position dite de verticalisation de la structure. Selon l'invention, le premier quadrilatère déformable présente des extrémités supérieures sur lesquelles sont montées le deuxième quadrilatère déformable, le deuxième quadrilatère déformable étant monté articulé à l'extrémité d'une bielle fixée au châssis par un axe d'articulation de manière que lors du déplacement des quadrilatères déformables entre les états stables replié et déplié, le repose-pieds évolue selon une trajectoire rétro-descendante et inversement lors du déplacement des quadrilatères déformables entre les états stables déplié et replié.

To achieve such an objective, the object of the invention relates to a verticalization wheelchair comprising a frame provided with wheels defining a support polygon and supporting an articulated structure comprising:

• a first deformable quadrilateral supporting a seat and having two lower ends mounted on the frame;
• a second deformable quadrilateral supporting a footrest;
• and an articulated structure raising-lowering control system comprising a motor member interposed between the frame and the articulated structure and able to control the displacement of the deformable quadrilaterals between a folded stable state corresponding to a so-called seated position of the structure and a state unfolded stable corresponding to a position called verticalization of the structure. According to the invention, the first deformable quadrilateral has upper ends on which are mounted the second deformable quadrilateral, the second deformable quadrilateral being mounted articulated to the end of a connecting rod fixed to the frame by a hinge pin so that when the displacement of the deformable quadrilaterals between the folded and unfolded stable states, the footrest evolves in a backward-descending trajectory and vice versa during the displacement of the deformable quadrilaterals between the unfolded and folded stable states.

• le premier quadrilatère déformable comporte deux biellettes parallèles entres elles dont les extrémités inférieures sont montées par des axes sur le châssis tandis que les extrémités supérieures des biellettes sont montées par des axes sur le deuxième quadrilatère déformable, avec l'une des extrémités supérieures d'une biellette étant montée sur l'assise par l'un de ces axes ;
• le deuxième quadrilatère déformable comporte deux barres rigides parallèles entre elles dont les extrémités inférieures sont montées par des axes sur le repose-pieds, les deux barres rigides étant reliées entre elles par une barre transversale montée sur les axes d'articulation des extrémités supérieures des biellettes du premier quadrilatère déformable ;
• le deuxième quadrilatère déformable est monté articulé par un maneton sur un axe monté à l'extrémité de la bielle fixée au châssis par un axe d'articulation ;
• la structure articulée comporte un troisième quadrilatère déformable supportant un dossier et monté par des axes sur les barres rigides du deuxième quadrilatère déformable ;
• la structure articulée est montée sur le châssis par des quadrilatères déformables qui sont organisés en deux ensembles latéraux ;
• la structure articulée est montée sur le châssis par des quadrilatères déformables qui sont organisés sous la forme d'une colonne centrale ;
• l'organe moteur est interposé entre le châssis et le deuxième quadrilatère déformable ;
• des roues avant de traction reliées à une motorisation.

The wheelchair according to the invention also comprises in combination one and / or the other of the following additional characteristics:

• the first deformable quadrilateral comprises two rods parallel to each other whose lower ends are mounted by axes on the frame while the upper ends of the links are mounted by axes on the second deformable quadrilateral, with one of the upper ends of a connecting rod being mounted on the seat by one of these axes;
• the second deformable quadrilateral comprises two rigid bars parallel to each other whose lower ends are mounted by pins on the footrest, the two rigid bars being interconnected by a transverse bar mounted on the hinge pins of the upper ends of the links the first deformable quadrilateral;
• the second deformable quadrilateral is mounted articulated by a pin on an axis mounted at the end of the rod fixed to the frame by a hinge pin;
• the articulated structure comprises a third deformable quadrilateral supporting a backrest and mounted by pins on the rigid bars of the second deformable quadrilateral;
• the articulated structure is mounted on the chassis by deformable quadrilaterals which are organized in two lateral assemblies;
• the articulated structure is mounted on the frame by deformable quadrilaterals which are organized in the form of a central column;
• the motor member is interposed between the frame and the second deformable quadrilateral;
• traction front wheels connected to a motor.

• La Figure 1 est une vue en perspective d'un exemple de réalisation d'un fauteuil roulant conforme à l'invention.
• La Figure 2 est une vue de côté du fauteuil roulant conforme à l'invention en position assise.
• La Figure 3 est une vue de côté d'un fauteuil roulant conforme à l'invention dans une position intermédiaire de verticalisation.
• La Figure 4 est une vue de côté du fauteuil roulant conforme à l'invention en position de verticalisation.
• Les Figures 5 et 6 sont des vues de dessus du fauteuil de verticalisation en position respectivement assise et de verticalisation.

Various other characteristics appear from the description given below with reference to the accompanying drawings which show, by way of non-limiting examples, embodiments of the subject of the invention.

• The Figure 1 is a perspective view of an exemplary embodiment of a wheelchair according to the invention.
• The Figure 2 is a side view of the wheelchair according to the invention in a sitting position.
• The Figure 3 is a side view of a wheelchair according to the invention in an intermediate position of verticalization.
• The Figure 4 is a side view of the wheelchair according to the invention in vertical position.
• The Figures 5 and 6 are views from above of the standing chair in respectively seated position and verticalization.

As is more specifically apparent from the drawings, the subject of the invention relates to a wheelchair 1 comprising a chassis C delimiting a platform 2, equipped with front wheels 3 and rear wheels 4. According to the exemplary embodiment, the wheelchair 1 is a front wheelchair. The wheels 3 which are placed at the front of the chassis C are carrier and motor while the wheels 4 which occupy the rear part of the wheelchair, are steerable and adjustable by means of a control mechanism 5 of any known type. in itself.

The wheels 3, 4 define, by the points of contact with the ground T, a support or lift polygon in which is positioned the mass or load P represented by the articulated structure S ( Fig. 5, 6 ). The front wheels 3 are mounted on the chassis C by means of bearings and can advantageously be associated with a drive 6 of reversible rotation drive such as one or more electric motors, capable of being powered from a embedded source and arranged on the platform 2. Of course, the wheelchair 1 is equipped with a moving control unit such as a joystick for controlling the direction and movement of the wheelchair 1.

The chassis C supports an articulated structure S comprising a seat A, a backrest D and a footrest R. In known manner, articulated structure S is organized to be able to occupy a folded stable state corresponding to a so-called sitting position as illustrated in FIGS. Fig. 2 and 5 and an unfolded stable state corresponding to a position of verticalization as illustrated by the Fig. 1 , 4 and 6 .

In these two stable positions and by means known in the art and not shown, the articulated structure S is able to support a disabled or disabled in a sitting position and in a vertical position respectively.

According to the invention, the articulated structure S is organized so that the seat A is carried by the frame C via a first deformable quadrilateral I organized in the illustrated example, into two lateral assemblies ( Fig. 1 ). Each set of the first deformable quadrilateral I, supports a seat A and comprises a first link 10 and a second link 11 extending parallel to each other. These rods 10, 11 have lower ends 10i , 11i and opposite, upper ends 10s, 11s. The lower ends 10i, 11i of the rods 10, 11 are mounted articulated on the chassis C via pins 14, 15 respectively . For this purpose, the chassis C comprises, for each set of the first deformable quadrilateral I , an amount C1 rising substantially vertically from the rear of the frame and supporting the axes 14, 15 extending horizontally between them and on which the lower ends of the rods 10, 11 are hinged mounted. One of the upper ends of a link, namely the end 10s of the first link 10 in the illustrated example is mounted articulated on the seat A by an axis 16 placed substantially in the middle part of the lower face of the sitting A.

The upper end 11s of the other link, namely the second link 11 in the illustrated example, is mounted articulated by an axis 17 on a second deformable quadrilateral II supporting the footrest R. Finally, the upper ends 10s, 11s rods 10 and 11 are interconnected by a transverse bar 19 mounted along the axes 16 and 17. The first deformable quadrilateral I thus comprises the links 10, 11 interconnected at one of their ends by a post C1 , by being articulated about the axes 14, 15 , and at the other of their ends by the bar 19, being articulated about the axes 16, 17. In the folded state ( Fig. 2 ), the rods 10 , 11 extend from the amounts C1 forward in a slightly inclined direction relative to the horizontal.

According to the invention, the upper ends 10s, 11s of the first deformable quadrilateral I are mounted on a second deformable quadrilateral II supporting the footrest R and organized in the example shown in two lateral assemblies. Each set of the second deformable quadrilateral II comprises a first rigid bar 20 mounted above a second rigid bar 21. These rigid bars 20, 21 are mounted parallel to each other and have lower ends 20i, 21i located in the front portion of the wheelchair and opposite upper ends 20s, 21s.

The two rigid bars 20, 21 are interconnected in their central parts, by the transverse bar 19 mounted on the rigid bars 20, 21 by the axes 16, 17 of articulation of the upper ends of the rods 10, 11 of the first deformable quadrilateral . The transverse bar 19 thus constitutes a mobile part common to the first deformable quadrilateral I and the second deformable quadrilateral II .

The lower ends 20i, 21i of the rigid bars 20, 21 are mounted by pins 24, 25 on the footrest R. For this purpose, the footrest R comprises a connecting plate 28 on which the pins articulation 24 and 25 of the rigid bars 20, 21. Each set of the second deformable quadrilateral II thus comprises the two rigid bars 20 and 21 interconnected at one of their ends, by the transverse bar 19 being hinged about the axes 16 , 17 and at the other of their ends, by the connecting plate 28 being articulated about the axes 24, 25.

For each set of the second deformable quadrilateral II, the footrest R comprises a leg 30 extending vertically downwardly being provided at its base, a sole 31 for a foot support of a user. Each leg 30 is articulated on the hinge pin 24 of the first rigid bar 20.

In the folded stable position ( Fig. 2 ), the two rigid bars 20 and 21 of the second deformable quadrilateral II extend substantially horizontally with the lower ends 20i , 21i located in front of the Wheelchair. In unfolded position ( Fig. 4 ), the two rigid bars 20 and 21 extend substantially vertically being brought closer to each other with the lower ends 20i, 21i positioned in a low position.

The second deformable quadrilateral II is articulated at the end of a connecting rod 40 fixed to the frame C by a hinge pin 41. The link 40 carries a hinge axis 43 for the second deformable quadrilateral II. For this purpose, a crossmember 44 is fixed between the second rigid bars 21 of the two sets of the second deformable quadrilateral II, and is provided with a crankpin 45 mounted articulated on the axis 43 carried by the rod 40. In the folded stable position ( Fig. 2 ), the link rod 40 of the second deformable quadrilateral II extends towards the front of the chair being inclined relative to the horizontal by a value for example of the order of 45 °.

During the transition from the folded stable position to the unfolded stable position ( Fig. 4 ), the connecting rod 40 pivots rearwardly about the hinge axis 41 to the frame, to exceed in the unfolded position, slightly vertical upright position.

According to an advantageous characteristic of embodiment, the articulated structure S comprises a third deformable quadrilateral III supporting a file D and organized in the illustrated example in two lateral assemblies ( Fig. 1 ). Each set of the third deformable quadrilateral III comprises a backrest D mounted hinged by an axis 50 on the first rigid bar 20, this axis 50 ensuring the articulation of a connecting flange 51 mounted articulated on the second rigid bar 21 by an axis d articulation 53.

In the folded stable position ( Fig. 2 ), the backrest D extends substantially vertically, perpendicularly to the seat A. In a stowed stable position ( Fig. 4 ), the backrest D extends substantially vertically parallel to the rigid bars 20, 21.

The wheelchair 1 according to the invention also comprises a control system 60 in elevation / lowering of the articulated structure S. This control system 60 includes in particular a motor member 62 interposed between the frame C and the articulated structure S.

In the example shown, the motor member 62 is mounted articulated on the frame C by an axis 64 and acts on the seat A of the articulated structure S by a hinge pin 65 placed substantially of the lower face medial portion. of the seat A.

This drive member 62 is controlled to ensure the displacement of the deformable quadrilaterals I , II and III between the folded stable state corresponding to the so-called seated position of the articulated structure and an unfolded stable state corresponding to the so-called verticalization position of the articulated structure. . The first I and the second II deformable quadrilaterals are mounted so that during the displacement of the deformable quadrilaterals I and II between the folded and unfolded stable states, the footrest R evolves in a backward-descending trajectory and vice versa during the movement of the deformable quadrilaterals between the unfolded and folded stable states.

In the state according to Fig. 2 , the articulated structure S is in the folded position in a position such that the seat A is substantially horizontal and that the footrest R is located just in front of the front part of the chassis C and between the steering wheels 3.

When the user wishes to move from the folded stable position to the unfolded stable position, the motor member 62 is controlled, in extension to lift the constituent elements of the first deformable quadrilateral I supporting the seat A. Thus, the rods 10, 11 of the first deformable quadrilateral I are forced to pivot towards the rear of the chair in the direction of the arrow f1 ( Fig.3 ) along the axes 14 , 15 of articulation of the frame, in a circular trajectory having for center the axes 14 , 15 and for radius, the length of the rods 10, 11, this movement causing the lifting of the seat A namely the tilting of the seat A forward towards the floor.

The pivoting of the rods 10, 11 also leads to the displacement of the hinge pins 16 , 17 on the second deformable quadrilateral II.

Thus, the rigid bars 20, 21 pivot towards the ground T in the direction of the arrow f2, around the hinge pins 16, 17 of the rods 10, 11 and the hinge axis 43 of the rod 40. of this movement, the rigid bars 20, 21 follow a path defined by the quadrilateral passing through the hinge pins 14, 15, 16 and 17 and the hinge pin 43 carried by the rod 40. The pivoting of rigid bars 20, 21 and in particular lower ends 20i, 21i downwards, causes the pivoting of the footrest R downwards and back of the chair. Thus, as is clear from the comparison of Fig. 2 to 4 , the footrest R evolves in a backward-descending trajectory during the transition from the folded stable state to the unfolded stable state. Indeed, between these two stable states, ( Fig. 2 and 4 ), the footrest R has moved back towards the back of the wheelchair while descending towards the ground T. Thus, in a stable unfolded position ( Fig. 4 ) the footrest R is closer to the ground T than to the folded position ( Fig. 2 ) and has undergone a retro-displacement. The lowering of the footrest R is conferred by the constructive characteristics of the second deformable quadrilateral II .

The characteristics of the deformable quadrilaterals I , II , III are chosen by construction so that, after the displacement of the drive member 62, the seat A and the backrest D are substantially placed in vertical alignment while the footrest R retrofit included within the support polygon defined by the wheels 3, 4.

It appears, comparing Fig. 5 and 6 , that the mass or load P that the articulated structure S represents between the folded stable position ( Fig. 5 ) and the defined stable position ( Fig. 6 ) remains included in the support polygon defined by the wheels 3 , 4 .

Of course, a reverse operation to the operation described above is established when the motor member 62 is controlled in retraction to bring the articulated structure S from its upright position to the seated position.

It follows from the foregoing description that the wheelchair according to the invention uses the force of gravity to effect the movement of verticalization of the user. This displacement principle makes it possible to reduce the mechanical stresses supported by the articulated structure S, compared with existing solutions.

Another advantage of the chair according to the invention relates to obtaining a better stability for the user in a vertical position due to the lowering of the footrest R in this position. The combination of this downward verticalization with a wheelchair for example front wheel drive, provides a compact chair, with maintenance of the user load inside the lift polygon defined by the wheels 3 , 4 .

In the exemplary embodiments illustrated in the drawings, the deformable quadrilaterals are organized in two lateral sets, but it is clear that the deformable quadrilaterals can be made in a columnar form by being grouped on either side of the anteroposterior plane of vertical symmetry.

Claims (9)

1. A lifting wheelchair including a chassis (C) provided with wheels defining a support polygon and supporting an articulated structure (S) including:

   - a first deformable quadrilateral (I) supporting a seat (A) and having two lower ends (10i, 11i) mounted on the chassis,

   - a second deformable quadrilateral (II) supporting a footrest (R),

   - and a raising-lowering control system (60) of the articulated structure (S) including a driver (62) interleaved between the chassis (C) and the articulated structure (S) and capable of controlling the displacement of the deformable quadrilaterals (I, II) between a stable retracted state corresponding to a so-called seating position of the structure and a stable deployed state corresponding to a so-called lifting position of the structure,

   characterized in that the first deformable quadrilateral (I) has upper ends (10s, 11s) on which are mounted the second deformable quadrilateral, the second deformable quadrilateral (II) being mounted articulated at the end of a rod (40) attached to the chassis by a hinge pin (41) so that during the displacement of the deformable quadrilaterals between the retracted and deployed states, the footrest follows a retracting-descending trajectory and conversely during the displacement of the deformable quadrilaterals (I, II) between the deployed and retracted states.
2. The lifting wheelchair according to claim 1, characterized in that the first deformable quadrilateral (I) includes two mutually parallel tie rods (10, 11) the lower ends (10i, 11i) of which are mounted by pins (14, 15) on the chassis while the upper ends (10s, 11s) of the tie rods are mounted by pins (16, 17) on the second deformable quadrilateral, with one of the upper ends of a tie rod (10) being mounted on the seat by one (16) of these pins.
3. The lifting wheelchair according to claim 2, characterized in that the second deformable quadrilateral (II) includes two mutually parallel rigid bars (20, 21) the lower ends (20i, 21i) of which are mounted by pins (24, 25) on the footrest, the two rigid bars (20, 21) being connected together by a transverse bar (19) mounted on the hinge pins (16, 17) of the upper ends of the tie rods (10, 11) of the first deformable quadrilateral.
4. The lifting wheelchair according to one of claims 1 to 3, characterized in that the second deformable quadrilateral (II) is mounted articulated by a crank pin (45) to a pin (43) mounted on the end of the rod (40) attached to the chassis by a hinge pin (41).
5. The lifting wheelchair according to one of claims 1 to 4, characterized in that the articulated structure (S) includes a third deformable quadrilateral (III) supporting a backrest (D) and mounted by pins on the rigid bars of the second deformable quadrilateral.
6. The lifting wheelchair according to one of claims 1 to 5, characterized in that the articulated structure (S) is mounted on the chassis (C) by deformable quadrilaterals (I, II, III) which are organized into two lateral sets.
7. The lifting wheelchair according to one of claims 1 to 5, characterized in that the articulated structure (S) is mounted on the chassis (C) by deformable quadrilaterals which are organized in the form of a central column.
8. The lifting wheelchair according to claim 1, characterized in that the driver (62) is interleaved between the chassis (C) and the second deformable quadrilateral (II).
9. The lifting wheelchair according to one of claims 1 to 8, characterized in that it includes front traction wheels (3) connected to a motor drive (6).

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