EP2441424B1 - Wheelchair provided with foot-rest - Google Patents

Description

The present invention relates to a wheelchair equipped with footrest, as conventionally used to allow a disabled person to move relative to the ground and to adopt different positions, such as sitting, standing or lying, depending his occupation and / or pathology.

Such wheelchairs are used, for example, by myopaths and paraplegics.

It is known to equip such wheelchairs with footrests which extend, on the front and downwards, from the seat of an armchair and which are equipped with pallets intended to receive support , on the top, the feet of a user. On some chairs, these footrests are adjustable, that is to say they can be rotated about an axis perpendicular to a direction of advance of the chair. Once pivoted into a configuration deemed comfortable for the user, each footrest is immobilized in this position. This immobilization imposes a constant orientation of the legs of the user relative to his thighs, while the user may be required to adopt several positions, including sitting, lying or semi-reclining. This can be uncomfortable.

In addition, some chairs called "verticalizers" can bring the user in a vertical position close to standing. In this case, during the transition from a sitting position to the upright position, the footrests are generally in the extension of the seat. This has the consequence that the user perceives that the distance available for his legs decreases. It has the feeling that the pallets of the footrests "back", which proves unpleasant and can bring its lower limbs in a semi-inflected configuration that is uncomfortable and tiring and that does not allow the blockage of the knee joint to provide effective upright support (see Figure 8 embodiment of the US-A-5,356,172 who tries to solve these disadvantages).

It is these drawbacks that the invention intends to remedy more particularly by proposing a new wheelchair which is more comfortable than those of the state of the art.

For this purpose, the invention relates to a wheelchair comprising at least one chassis equipped with connecting members to the ground, a seat supported by the frame, a backrest articulated relative to the seat around a first axis and two rests feet each comprising an articulated arm relative to the seat around a second axis parallel to the first axis and a pallet supported by this arm. According to the invention the pallet of each footrest is movable in translation along the arm and the chair comprises, for each footrest, a first actuator for adjusting the angular position of the arm around the second axis and a second actuator for adjusting the position of the pallet parallel to a longitudinal axis of the arm.

Thanks to the invention, the two actuators allow to adapt, in use of the chair, the position of the pallets of each footrest, depending on the position adopted sitting, lying, semi-elongated or verticalized. In particular, the distance between the pallet of each footrest on which bears a foot of the user and the axis of articulation of the arm of this footrest on the seat can be adjusted to take account of changes orientation of the leg of a user relative to his thigh. This adjustment can be achieved independently for each of the footrests since a first actuator and a second actuator are provided for each footrest.

• Chaque actionneur est paramétrable.
• Chaque actionneur est un vérin électrique.
• Le premier actionneur est articulé sous l'assise et attaque le bras du repose-pied sur lequel il est également articulé.
• La palette d'un repose-pied est supportée par un chariot mobile le long du bras de ce repose-pied et soumis à l'action du deuxième actionneur.
• Un cale genou est monté sur le chariot.
• Le vérin formant le second actionneur est monté sur le bras et attaque le chariot.
• Le deuxième actionneur de chaque repose-pied est apte à faire varier la distance entre la palette et le deuxième axe d'articulation lors d'une verticalisation du fauteuil.
• Le fauteuil comprend des moyens paramétrables de réglage de la hauteur, mesurée parallèlement à la hauteur du dossier, d'un dégagement sacral défini entre l'assise et le dossier. Dans ce cas, les moyens paramétrables précités sont avantageusement aptes à faire varier la hauteur du dégagement sacral lors d'une verticalisation du fauteuil.

According to advantageous but non-mandatory aspects of the invention, such a chair can incorporate one or more of the following features taken in any technically permissible combination:

• Each actuator is configurable.
• Each actuator is an electric cylinder.
• The first actuator is articulated under the seat and attacks the arm of the footrest on which it is also articulated.
• The pallet of a footrest is supported by a carriage movable along the arm of the footrest and subjected to the action of the second actuator.
• A knee pad is mounted on the carriage.
• The cylinder forming the second actuator is mounted on the arm and attacks the carriage.
• The second actuator of each footrest is able to vary the distance between the pallet and the second axis of articulation during a verticalization of the chair.
• The chair comprises parametric means for adjusting the height, measured parallel to the height of the backrest, a sacral clearance defined between the seat and the backrest. In this case, the aforesaid parametric means are advantageously able to vary the height of the sacral clearance during a verticalization of the chair.

• la figure 1 est une vue en perspective, par l'avant, d'un fauteuil roulant conforme à l'invention,
• la figure 2 est une vue de côté, dans le sens de la flèche Il à la figure 1, de l'assise, du dossier, des accoudoirs, des repose-pieds et de certains moyens d'actionnement du fauteuil de la figure 1,
• la figure 3 est une vue en perspective par l'arrière des éléments du fauteuil représentés à la figure 2,
• la figure 4 est une vue de côté comparable à la figure 2 lorsque le fauteuil est dans une deuxième configuration d'utilisation, dite verticalisée, et
• la figure 5 est une vue en perspective par l'arrière des éléments du fauteuil représentés à la figure 4.

The invention will be better understood and other advantages thereof will appear more clearly in the light of the following description of an embodiment of a wheelchair in accordance with its principle, given solely as an example. and with reference to the accompanying drawings in which:

• the figure 1 is a perspective view, from the front, of a wheelchair according to the invention,
• the figure 2 is a side view, in the direction of the arrow It to the figure 1 , the seat, the backrest, the armrests, the footrests and certain means of actuating the chair of the figure 1 ,
• the figure 3 is a perspective view from behind of the chair elements shown in figure 2 ,
• the figure 4 is a side view comparable to the figure 2 when the chair is in a second configuration of use, called verticalized, and
• the figure 5 is a perspective view from behind of the chair elements shown in figure 4 .

The standing chair 2 shown in the figures comprises a motor assembly 4 comprising two unrepresented electric motors powered by storage batteries arranged under a cowling and supported by a chassis 6 partially visible at the figure 1 because dressed by body parts. The motors drive wheels 7 so-called motor supported by the frame 6. The frame 6 also supports the front wheels 8 crazy obstacle clearance and rear wheels 9 anti-tilt.

The chair 2 comprises a seat 10 covered by a cushion 12. The chair 2 also comprises a backrest 20 which extends above the seat 10, parallel to an axis Z which defines its height H20. This Z axis is generally vertical but may have a horizontal component, depending on the orientation of the backrest 20 relative to the seat 10.

According to one aspect of the invention which is not shown in figure 1 for the clarity of the drawing, but in the other figures, the chair 2 is equipped with a headrest 30 supported by the backrest 20.

The left armrest 42 of the chair 2 is provided with a control member 50, joystick type, and a control screen 60. The other armrest 41, namely the right armrest, is devoid of it. Depending on the choice of the user, the elements 50 and 60 may alternatively be mounted on the armrest 41.

The height H20 of the backrest is measured, with respect to the upper surface 126 of the seat 10, parallel to the axis Z. The width 120 of the backrest 20 is measured parallel to a Y axis perpendicular to the Z axis and parallel to the rear edge 122 of the cushion 12.

X is an axis perpendicular to the Y and Z axes. The X axis is perpendicular to the back 20.

The back 20 comprises a welded main frame 21 which is articulated on the frame 11 of the seat 10 around a Y20 axis parallel to the Y axis. The pivoting of the backrest 20 around the axis Y20 is controlled by an electric jack 25 which drives a connecting rod 26 in clevis articulated on the frame 11 of the seat 10

The backrest 20 further comprises an auxiliary frame 23 movable in translation parallel to the axis Z relative to the main frame 21. An electric jack 27, mounted between the frames 21 and 23 and controlled for this purpose, moves the carriage 23 relative to the carriage 21 in the direction of the double arrow F1. Three subassemblies 22, 24 and 26 are mounted on the frame 23 and distributed over the height of the backrest 20, along the Z axis. The subassembly 26 is the closest to the seat 10, while the subassembly 22 is the farthest and the subassembly 24 is disposed along the Z axis between the subassemblies 22 and 26. The subassemblies 22, 24 and 26 are not contiguous, in that there are two spaces E and E 'respectively between the lower edge of the subassembly 22 and the upper edge of the subassembly 24 and between the lower edge of the subassembly 24 and the upper edge of the subassembly 26.

In the present description, the chair 2 is considered in the configuration of the Figures 1 to 3 and a part where an object is qualified as "superior" if it is oriented upwards in this configuration and "inferior" if it is oriented downwards. Thus, a lower portion of the back 20 is oriented towards the seat 10, when an upper portion is oriented away from this seat.

The chair 2 is also equipped with two footrests 101 and 102 which are arranged, relative to the seat 10, to receive the feet and legs of a user.

The footrest 101 is arranged on the right of the armchair 2, on the same side as the armrest 41, while the footrest 102 is arranged on the left of the armchair, on the same side as the armrest 42.

The footrest 102 comprises an arm 1021 hinged to the frame 11 of the seat 10 about an axis Y102 parallel to the axis Y20. In both configurations shown in the figures, the arm 1021 extends below the Y102 axis. The arm 1021 is provided with a lug 1022 on which is articulated the rod 1042 of a jack 104 whose body is articulated on a lug 112 of the frame 11. The jack 104 thus makes it possible to pivot the arm 1021 around the axis Y102, as represented by the double arrow R1 on the figure 2 .

The jack 104 is an electric jack, easily adjustable and controlled by an electronic control unit belonging to the chair 2. This unit is not shown in the figures, for clarity of the drawing.

A21 is the central longitudinal axis of the arm 1021. This axis A21 extends in a radial direction relative to the axis Y102 and its angular orientation around the axis Y102 depends on the action of the cylinder 104.

The footrest 102 also comprises a carriage 1023 mounted to be movable in translation on the arm 1021, along the axis A21. Thus, the carriage 1023 can take various positions along the axis A21, as shown respectively in solid lines and in phantom lines at the figure 2 .

A pallet 1024 is mounted on the carriage 1023 by being articulated about an axis B24 perpendicular to the axis A21. The pallet 1024 can thus go from the position shown in the figures where it extends perpendicular to the axis A21 to a retracted position, folded against the carriage 1023.

In the position shown in the figures, the pallet 1024 can receive, on its upper surface 1024S, the left foot of a user of the chair 2.

An electric jack 106 is mounted on the arm 102 and its rod 1062 drives a pin 1025 secured to the carriage 1023. Thus, the cylinder 106 allows to control the position of the carriage 1023 along the axis A21. The jack 106 thus makes it possible to position the pallet 1024 at a distance d variable from the axis Y102, this distance being measured parallel to the axis A21. We denote d1 the value of the distance d in the configuration of Figures 1 to 3 .

To the figure 2 , the double arrow F2 shows the possibility of translation of the carriage 1023 relative to the arm 1021.

The cylinder 106 may be of the same type as the cylinder 104. Alternatively, it may be a cylinder of another type. In all cases, the jack 106 is easily parameterizable and can be controlled by the central control unit of the chair 2.

The carriage 1023 is in the form of a U-shaped cross-section with a flat bottom, which enables it to define a partial receiving volume of the body 1064 of the jack 106 which thus protects mechanically.

On the front of the carriage 1023, that is to say the opposite of the cylinder 106, is mounted a pad 1026 for receiving in support of the back of the leg of a user. This pad 1026 is made of flexible material and mounted in an adjustable manner on the carriage 1023, as shown by the oblong slots visible at figure 1 .

A knee block 1027 is also mounted on the carriage 1023 and comprises a pad 1028 made of flexible material and intended to support the upper part of the tibia, close to the knee, a user and a link rod 1029 which extends between the pad 1028 and the carriage 1023. As the knee block 1027 is mounted on the carriage 1023, it undergoes the same translational movements as the paddle 1024, under the action of the jack 106.

The footrest 101 is identical to the footrest 102. It includes an arm 1011 articulated on the frame 11 about an axis Y101 parallel to the axis Y20. In practice, the axes Y101 and Y102 are merged. The footrest 101 also comprises a tab 1012 which is attacked by the rod 1032 of a jack 103 similar to the jack 104 and hinged to the frame 11. A carriage 1013 movable along a longitudinal axis A11 of the arm 1011 supports a pallet 1014 for receiving, on its upper surface 1014S, the right foot of a user. A cylinder 105 visible by tearing at the figure 5 is mounted on the arm 1011 and its rod 1052 attacks a pin 1015 integral with the carriage 1013. A pad 1016 is mounted on the front of the carriage 1013, as well as a knee pad 1017 comprising a pad 1018 and a rod 1019.

The cylinders 103 and 105 are respectively identical to the cylinders 104 and 106.

The cylinders 103, 104, 105 and 106 constitute actuators that adjust the position of the pallets 1014 and 1024 according to the morphology of the user and the position of use of the wheelchair 2. These cylinders are to be distinguished from the members for adjusting the position of the pallets of the footrests of conventional wheelchairs, these adjustment members being intended to be handled only when a user takes possession of his wheelchair, to adapt it to the morphology of the user, without being then manipulated again. On the contrary, the actuators 103 to 106 of the invention make it possible to change the position of the pallets 114 and 124 not only during the adjustment of the chair 2 but also during use.

A main jack 110 is mounted under the frame 11 and allows to control the position and orientation of the seat 10 relative to the frame 6. This function is known, it is not described in detail.

During verticalization of the user, that is to say during the passage of the configuration of the Figures 1 to 3 to those of figures 4 and 5 , the jacks 103 and 104 are actuated to rotate the arms 1011 and 1021 about the axes Y101 and Y102. In addition, on this occasion, the cylinders 105 and 106 are actuated to lower the pallets 1014 and 1024, that is to say increase the distance d between these pallets and the Y101 or Y102 axis to a value d2 upper to the value d1. This movement of the pallets downwards relative to the seat 10 makes it possible to accommodate the legs and thighs of the user, at the level of the footrests 101 and 102, on the one hand, and at the level of the seat 10, on the other hand, without the user feeling "compressed" above the pallets 1014 and 1024 and allowing him to lock the articulation of his knees in standing configuration.

In addition, since the control of the pallets 1014 and 1024 is individual, their position in each of the configurations of use of the chair, as well as in the intermediate configurations of passage between these positions, can be adapted to the morphology or the pathology of the user.

A sacral clearance D defined between, on the one hand, the upper surface 126 of the cushion 12 in the vicinity of its rear edge 122 and on the other hand, the lower edge 262 of the subassembly 26 is considered. This sacral clearance D allows to receive the buttocks and lower back of a user, without exerting too much pressure on this part of his anatomy.

HD _{1 is} the height of the sacral clearance, measured parallel to the Z axis, sitting configuration of the chair 2 shown in FIGS. Figures 1 to 3 .

If this height is kept constant during the verticalization of a user, insofar as it is supported by its feet, on the pallets 1014 and 1024 of the footrests 101 and 102, the user tends to slide downwards relative to the backrest 20. To limit this relative sliding movement, the jack 27 which controls the displacement of the auxiliary frame 23 relative to the main frame 21 of the backrest 20, is controlled, during verticalization, to reduce the height sacral clearance, up to an HD ₂ value lower than HD ₁ .

Thus, the fact of installing the subassemblies 22, 24 and 26 on the auxiliary frame 23 and of controlling the displacement of this auxiliary frame parallel to the axis Z, by means of an electric actuator 27, makes it possible to progressively adapt the position of the part of the backrest 20 which is in contact with the back of the user, namely the subassemblies 22, 24 and 26, relative to the seat 10, according to the progressive verticalization of a user. The cylinder 27 makes it possible to progressively reduce the height of the sacral clearance D, from the value HD ₁ to the value HD _2, and thus improves the comfort of the user.

Conversely, when the cylinders of the chair 2 are actuated to pass it of the verticalized configuration of figures 4 and 5 to the sitting configuration of Figures 1 to 3 the distance between the pallets 1014 and 1024 and the hinge axes Y101 and Y102 of the footrests 101 and 102 is reduced from the value d2 to the value d1 and the height of the sacral clearance D is increased from the value HD ₂ to the value HD ₁ .

Like the cylinders 103 to 106, the actuator 27 can be parameterized, which makes it possible to adjust the values HD ₂ and HD ₁ according to the morphology and the pathology of the user, as well as the curve of variation of the height. sacral clearance during verticalization or during the reverse movement.

Claims (10)

1. Wheelchair (2) comprising at least:

   - one frame (6) equipped with components (6, 7, 8) for contact with the ground;

   - one seat (10) supported by the frame;

   - one backrest (20) which is articulated in relation to the seat about a first axis (Y20);

   - two footrests (101, 102), each of which comprises an arm (1011, 1021), which is articulated in relation to the seat about a second axis (Y101, Y102) parallel to the first axis, and a plate (1014, 1024) supported by the said arm;
   characterised in that the plate (1014, 1024) of each footrest (101, 102) is movable in translation along the arm (1011, 1021), and in that the chair (2) comprises, for each footrest (101, 102):

   - a first actuator (103, 104) for adjusting the angular position of the arm about the second axis (Y101, Y102) and

   - a second actuator (105, 106) for adjusting the position of the plate (1014, 1024) parallel to a longitudinal axis (A11, A21) of the arm (1011, 1021).
2. Wheelchair according to claim 1, characterised in that each actuator (103, 104, 105, 106) is configurable.
3. Wheelchair according to either of the preceding claims, characterised in that each actuator is an electric jack (103, 104, 105, 106).
4. Wheelchair according to claim 3, characterised in that the first actuator (103, 104) is articulated under the seat (10) and affects the arm (1011, 1021) of the footrest (101, 102) on which it is likewise articulated.
5. Wheelchair according to one of the preceding claims, characterised in that the plate (1014, 1024) of a footrest (101, 102) is supported by a carriage (1013, 1023) which is movable (F2) along the arm (1011, 1021) of the said footrest and is subject to the action of the second actuator (105, 106).
6. Wheelchair according to claim 5, characterised in that a knee chock (1017, 1027) is mounted on the carriage (1013, 1023).
7. Wheelchair according to claim 3 and either of claims 5 or 6, characterised in that the jack (105, 106) forming the second actuator is mounted on the arm (1011, 1021) and affects the carriage (1013, 1023).
8. Wheelchair according to one of the preceding claims, characterised in that the second actuator (105, 106) of each footrest (101, 102) is actuated in order to vary the distance (dl, d2) between the plate (1014, 1024) and the second axis of articulation (Y101, Y102) when the chair is brought into the upright position.
9. Wheelchair according to one of the preceding claims, characterised in that it comprises configurable means (27) for adjusting the height (HD₁, HD₂), measured parallel to the height (H20) of the backrest (20), of a sacral clearance (D) defined between the seat (10) and the backrest.
10. Wheelchair according to claim 9, characterised in that the configurable means (27) are configured in order to vary the height (HD₁, HD₂) of the sacral clearance (D) when the chair (2) is brought into the upright position.

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