EP0155918B1

EP0155918B1 - Improvement in wheelchairs for disabled

Info

Publication number: EP0155918B1
Application number: EP85830069A
Authority: EP
Inventors: Amici Ivano
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-03-19
Filing date: 1985-03-18
Publication date: 1989-05-31
Also published as: ES541389A0; EP0155918A3; ATE43492T1; EP0155918A2; ES8605372A1; IT8447887A0; IT1209917B; DE3570591D1

Abstract

Wheelchair for disabled consisting of a frame (6) which includes a chair-back (1), a seat (7), a leg rest (11) and a foot rest (12) connected to each other by hinges, and two movable arms (2) said wheelchair comprising in combination, lever and bar (5,16,30), symmetrically positioned on both sides of the wheelchair and connected together orizontally by bars which are fixed to the frame (6) in such a way that the motion of any one of the elements of the wheelchair will result in the motion of the others, actuators (23, 24) which control the above said movements, and means to control the actuators themselves.

Description

The object of the present invention is to improve wheelchairs for disabled. In particular, the invention relates to a wheelchair which has the peculiar characteristic of enabling movement in all directions, either horizontally, on the basis of already known technical principles, or, independently, vertically so that the patient may assume any position from lying horizontally to standing, using slow movements and without physical efforts.
Wheelchairs capable of raising a disabled to an upright position or to a lying position by operating an activator are already known in the art.
Said chairs allow the disabled to reach objects situated within the height reachable by persons and, therefore, to be more independent in usual home and work environments.
In WO 79/00647 is described a wheelchair of the above type particularly simply constructed, which can perform said functions by a simple rod system.
Said rod system comprises two devices shaped as parallelogram, each including four arms mutually connected by means of hinges and hinged to the chassis of the wheelchairs.
Main object of the present invention is that of providing a wheelchairs of the above mentioned type realized in a still more simple way and allowing an easier maneuverability of the chair.
It is well clear that a solution like that provided by the present invention has the undeniable advantages of enabling the patient to become completely independent and of avoiding the patient having to remain for a long time in the same position.
It is the specific object of the present invention a wheelchair for a disabled person comprising a chassis, with wheels, a frame with chair-back, seat, leg rest, foot-rest and two movable arms, and a double symmetrical rods system, provided laterally with respect to the chassis and the frame, and connected to said chassis and frame; wherein each rods system comprises a first bar, parallel with respect to the seat, connected, at the back, to the seat by a second bar hinged to the seat and to the first bar, said first bar being, in front, coupled to the leg rest and hinged to a third bar hinged, at the other end, to the foot rest, the seat and the leg-rest are mutually hinged by a hinge; at least one load bearing castor is provided under the foot rest, and two actuator means are respectively provided between the chassis and the seat and between the chassis and the first bar; between said bars of said double symmetrical rods system being provided horizontal transverse connecting bars.
Preferably, said wheels are idle and lifted off the ground during the movement of the wheelchair in its upright position, the stability of the wheelchair being ensured by said at least one load bearing castor.
Again according to the invention, two load bearing castors are provided and each said castor is mounted at the end of the leg rest and is joined to said leg-rest by means of an element externally slidable along said leg rest and hinged to said second bar.
Said actuator means are, preferably, made of two linear electromagnetic actuators.
Working of one or the other of said actuators determines the motion of all the elements constituting the wheelchair from a horizontal position to a vertical one.
The main advantage of having equipped the wheelchair with linear electromagnetic actuators lies in the fact that in case of failure the wheelchair will remain temporarily blocked as it is and will not return abruptly to its original position, creating the easily imaginable consequences for the patient.
Moreover, according to the invention, said bar and lever means, which are positioned symmetrically on both sides of the wheelchair, include a horizontal bar, placed parallel to the seat and displaced towards the bottom, connected, at one end, to said seat by means of a semicircular bar and, in front, at the other end, to the leg rest, a profiled lever hinged, above, to said horizontal bar and, below, to the foot rest, transversal bars being provided for connecting the two symmetrical bar and lever systems rigidly together.
It should be noted that, according to the present invention, a second foot rest, parallel to the abovesaid one, slightly higher up and rigidly fixed to the leg rest, is provided in order to avoid the weight of the legs on the first foot rest from having any effect on the inclination of the system of parallelisms.
According to the invention said means to control the actuator means are advantageously a push-button control positioned on the arms, or levers, also positioned on the arms, or muscular impulse control, or vocal vibration control, or vocal code control means or remote drive control.
In a preferred embodiment two belts on the chair-back and on the leg rest are provided so as to prevent the patient from slipping down from the wheelchair when in a vertical position.
According to another preferred embodiment of the wheelchair of the present invention, said wheelchair comprises, in combination, two rear load-bearing wheels equipped with external rings, two front load-bearing idle wheels, one or two front rubber castors under the foot rest, two independent electrical motor reduction-units to control motion on the ground, a frame built with tubular elements to which the chair-back, the seat, the leg rest, the foot rest and the two movable arms are attached, two actuator means fixed, respectively, to the seat and to the leg rest, bar means and lever means hinged to said chair-back, leg rest and foot rest, and means to control said actuator means.
The invention will be disclosed, for illustrative and not for limitative purposes, according to some preferred embodiments with specific reference to the figures of the drawings enclosed, wherein:

Figure 1 is a lateral schematic view of the wheelchair according to the invention;
Figure 2 is a schematic plan view of the wheelchair of Figure 1;
Figures 3, 4 and 5 illustrate, in a schematic way, how the wheelchair work; and
Figure 6 is a schematic lateral view of a second embodiment of the wheelchair according to the invention.

With particular reference to Figure 1, reference (1) indicates the chair-back of the wheelchair of the invention and reference (2) indicates one of the two movable arms.
As it can be seen, the seat (7) and horizontal bar (5) are connected, hinged in (3) and (4) respectively, by means of a semicicular shaped bar (8). In front, said horizontal bar (5) is hinged in (10), being so connected to leg rest (11). In a parallel direction with respect to leg rest (11), a shaped lever (16) is provided hinged to the leg rest in (14) and to the foot rest in (15). By means of these parallelisms made of said bars and levers, which are provided symmetrically on both sides of the wheelchair, it is possible to ensure that the movement of only one among chair-back (1), seat (7), leg rest (11) or foot rest (12) will automatically determine the position of the other parts.
Figure 1 also schematically illustrates the rear load-bearing wheels (17), the front idle load-bearing wheels (18) and the interior load-bearing castor (19).
The foot rest (20) is provided to avoid the weight of the patient on foot rest (12) from having any effect on the inclination of the other parts.
The motive power necessary for the horizontal and vertical movements of the wheelchair is generated by an accumulator (21) (Figure 2).
All of the horizontal movements can be obtained by means of the separate controls (22) fixed to the frame near each rear wheel (17) which enable forward and backward motion of the wheelchair. Rotational motion is transmitted to the rear wheels (17) by means of a roller (13) keyed to the shaft projecting from the motor reduction-unit and compressed by a spring (not shown).
Figure 3 shows the linear actuators (23) and (24) hinged to the seat (7) in (25) and to the leg rest (11) in (26). Said actuators (24) and (25) are fixed below to the wheelchair frame (6) in (27) and (28).
In Figure 3 the patient is in a seated position. The arrow indicates the motion that the arms (2) can make.
Acting on the control (not shown), the patient can operate actuator (24), which in its turn, takes effect on the leg rest (11) and, consequently, by means of the parallelisms illustrated in Figure 1, on the foot rest (12), the seat (7), and the chair-back (1), so that the patient can assume any one of the intermediate positions between the one shown in Figure 3 and the one shown in Figure 4.
In its turn, by operating the actuator (23), hinged in (25) to the seat (7), the patient is enabled to assume position which vary between those in Figures 3 and 5, due to the presence of the abovesaid parallelisms.
It should be noted that, as illustrated in Figure 5, when the patient stands, the idle front wheels (18) are raised from the ground and the stability of the wheelchair is ensured by the anterior castor (19).
Figure 6, instead, shows an embodiment of the wheelchair according to the invention, which differs from the one described previously only in some of its constructional aspects, the main features which embody the innovative quality of the invention remaining unaltered.
In particular, it can be seen that the profile of frame 6 has been modified in its external form. This second embodiment allows advantageously to house in (29) a number of accumulators (21), (see Figures 2 and 3), greater than one.
To this end, it may be noted that actuator (23) can be fixed (32), instead of in (27) as in the case of the previous embodiment.
The semicircular shape bar (8) is in this case, replaced by a bar (30) which has the shape of a "seven".
Another constructive aspect which differs from the previously described embodiment is the one which concerns the position of castor (19).
In fact, in this case, the castor (19) is mounted on axis with the lever (11 ), instead of at the end of the foot rest (12) and is joined to the lever (11) by means of the element (31) which is slidable externally along said lever (11). The element (31) is hinged to the lever (16) in (15) in such a way that when the patient brings himself into an erect position (see Figure 5) equilibrium continues to be safeguarded by front castor (19).
This second embodiment is particularly suitable for street transportation both because of the possibility to provide for more than one accumulator (21) and because of the position of castor (19).
The present invention has been described with special reference to some of its specific embodiments but it is to be intended that variations and modifications may be made by those skilled in the art without departing from the scope of the invention as defined in the following claims.

Claims

1. A wheelchair for a disabled person comprising a chassis (6), with rear and front wheels (17, 18), a frame with chair-back (1), seat (7), leg rest (11), foot-rest (12, 20) and two movable arms (2), and a double symmetrical rods system (5, 8, 30; 16), provided laterally with respect to the chassis (6) and the frame, and connected to said chassis (6) and frame, wherein each rods system comprises a first bar (5), parallel with respect to the seat (7), connected, at the back, to the seat by a second bar (8, 30) hinged (3, 4) to the seat (7) and to the first bar (5), said first bar (5) being, in front, coupled to the leg rest (11) and hinged to third bar (16) hinged, at the other end, to the foot rest (12, 20); the seat (7) and the leg rest (11) and mutually hinged by a hinge (9); at least one load bearing castor (19) is provided under the foot rest (12, 20), and two actuator means (23, 24) are respectively provided between the chassis (6) and the seat (7) and between the chassis (6) and the first bar (5); between said bars of said double symmetrical rods system being provided horizontal transverse connecting bars.

2. A wheelchair according to claim 1, characterized in that said front wheels (18) are idle and lifted off the ground during the movement of the wheelchair in its upright position, the stability of the wheelchair being ensured by said at least one load bearing castor (19).

3. A wheelchair according to claim 1 or 2, characterized in that two load bearing castors (19) are provided.

4. A wheelchair according to claim 3, characterized in that each said castor (19) is mounted at the end of leg rest (11) and is joined to said leg rest (11) by means of an element (31) externally slidable along said leg rest (11) and hinged (15) to said second bar (16).

5. A wheelchair according to claims 1-4, characterized in that said actuator means (23, 24) are two linear electromagnetic actuators.

6. A wheelchair according to claims 1-5, characterized in that means to control the actuator means (23, 24) are provided, said means to control comprising a push button control positioned on the arms (2), or levers positioned on the arms (2), or muscular impulse control, or vocal vibration control, or vocal code control.