EP0324795B1 - Wheel-chair - Google Patents

Abstract

PCT No. PCT/EP87/00679 Sec. 371 Date May 5, 1989 Sec. 102(e) Date May 5, 1989 PCT Filed Nov. 5, 1987 PCT Pub. No. WO88/03399 PCT Pub. Date May 19, 1988.In order to produce a much simpler and in particular lighter-weight wheel-chair than existing models, and to achieve at the same time optimum rigidity and safety, the surface of the seat (3), back support (1) and side-walls (5) are designed as a self-supporting monocoque construction, in self-reinforced and/or foam plastic. The base (25) carried by the wheels (17,37) also consists of self-reinforcing and/or foam plastic. The monocoque construction and base are integrally formed and have a height adjustment feature.

Description

The invention relates to a wheelchair according to the preamble of claim 1.

Wheelchairs are known for example from DE-OS 29 46 391, DE-OS 32 39 472 and from DE-GM 85 21 183. All these wheelchairs have in common that they comprise a generally dismantled support frame or a dismountable substructure with tube supports, levers and rods, to which the two larger rear wheels with handrail, the front wheels and the seat structure are detachably attached.

Such wheelchairs with a metal base are relatively heavy and, due to the large number of individual parts, only very costly to produce.

Therefore, a sports wheelchair has already been proposed in DE-OS 35 26 985, which consists of a plastic frame with plastic rims and profile spokes and plastic sport grip rings. By using the plastic parts mentioned, this sports wheelchair is said to have a lower weight than conventional wheelchairs. Otherwise, the basic structure of this wheelchair is comparable to conventional wheelchairs, since a common base with rods is also used here.

A wheelchair which also contains parts made of plastic (including foam plastic) is also known from WO 85/01205.

A wheelchair for small children, but especially for dolls, has also become known from GB-A-1 216 476. This wheelchair, which is only suitable for the slightest loads, is made from a flat plastic injection molded part, with the various parts, such as backrests, side parts, feet reaching down to the axes, etc. being connected to one another via film hinges. When assembling the wheelchair, the parts on the film hinges must be folded over. For stabilization, a basket-like base with a front and rear axle is provided, the axles being inserted and secured through corresponding recesses on the four feet of the chair bent down over the film hinge. The plastic structure therefore works with flat-shaped plastic parts that do not withstand large loads due to the plastic hinges.

In contrast, it is an object of the present invention to provide a wheelchair which is simple in construction and inexpensive to manufacture and which, with a comparatively low weight, also has optimum rigidity and safety for adults. The wheelchair should have a high level of handling, driving and safety comfort. The seating comfort should be improved with simple means. Depending on the needs and requirements, a folding mechanism for such a wheelchair should also be possible. The object is achieved according to the features specified in claims 1, 10 and 44. Advantageous embodiments of the invention are specified in the subclaims.

The present invention is the first to choose a completely different conceptual path for a wheelchair. The The wheelchair according to the invention has an optimal rigidity due to its shell construction, which ensures a favorable force distribution in particular even with a one-piece support frame. The use of plastic makes it possible to carry out a lightweight construction even if the entire wheelchair is relatively compact. If foamed plastic is used for the support frame consisting of the seat, the backrest and the side walls, possible risks of injury can also be minimized by means of a homogeneous line design, because the individual linkages and levers required by the prior art are superfluous in the present solution. A substructure supported on the wheels also consists of foamed and possibly reinforced plastic. The use of hard and soft foam sections and parts can also increase the safety of the entire wheelchair and improve seating comfort.

The backrest can be raised to head height or can also be designed so that a headrest can be anchored to the backrest upper part.

The fact that the armrests can be carried out up to the footrest results in improved security against lateral impacts. In addition, an integrated circumferential bumper can also be formed at least on the footrest.

Since the shell-shaped support frame of the wheelchair consists of cellular expanded plastic material, soft-hard material combinations are also possible. The parts made of soft foam materials also serve as upholstery.

This corrosion-resistant material is also easy to care for and aseptic and therefore offers advantages when used in hospitals. In addition, the entire wheelchair is extremely powerful due to the high material damping values.

The described advantages result above all from the wheel according to the invention, which is designed as a complete plastic wheel. Since it is designed as a full wheel, the handrail can be integrated with. In addition, the full wheel can also be made of foamed plastic, so that it can also be produced cheaply and has an extremely low weight. As flat tires, the solid material can also be used, whereby softer plastic foam can be used on the tread compared to the rest of the wheel body. This also results in optimal shock absorption with easy and quiet running. The integrated handrail can also consist of softer plastic foam than the full-wheel material. Although from DE-OS 33 16 002 a handle on the wheel of a wheelchair has become known, which is also made of cellular expanded plastic, this handrail-shaped handrail must be equipped with conventional fastening elements in order to be attached to a conventional spoke wheel.

In addition, the advantages according to the invention can nevertheless also be achieved with a correspondingly firm and stable seat surface and backrest which cannot be collapsed in itself if a folding mechanism designed according to the invention is provided.

• Figur 1 : eine schematische perspektivische Darstellung der erfindungsgemäßen Rollstuhles;
• Figur 2 : eine schematische Längsschnittdarstellung;
• Figur 3 : eine auszugsweise schematische Querschnittdarstellung durch ein Rad und den angrenzenden Teil des Rollstuhles;
• Figur 4 : eine schematische Darstellung des Bremssystems;
• Figur 5 : eine perspektivische Ansicht eines weiteren Ausführungsbeispieles;
• Figur 6 : eine Detailschnittdarstellung durch das Rad;
• Figur 7 : eine Seitenansicht des Ausführungsbeispieles nach Figur 5;
• Figur 8 und 9 : zwei schematische Schnittdarstellungen einer Absenkvorrichtung für die Fußablage;

Further advantages, details and features of the invention result below from the exemplary embodiments illustrated with the aid of drawings. The following show in detail:

• Figure 1 is a schematic perspective view of the wheelchair according to the invention;
• Figure 2 is a schematic longitudinal sectional view;
• Figure 3: a partially schematic cross-sectional view through a wheel and the adjacent part of the wheelchair;
• Figure 4 is a schematic representation of the braking system;
• Figure 5 is a perspective view of another embodiment;
• Figure 6: a detailed sectional view through the wheel;
• Figure 7 is a side view of the embodiment of Figure 5;
• Figures 8 and 9: two schematic sectional views of a lowering device for the footrest;

A wheelchair is shown in the figures, which consists of a shell construction with a one-piece frame made of cellularly expanded plastic material. This one-piece frame construction comprises a backrest 1, a seat 3, side walls 5 which merge into armrests 7 on their upper side. The seat surface 1 and the side frame 5 are passed through from the armrest 7 to a footrest 9, which provides increased side protection.

Thanks to the use of foamed plastic material, the entire wheelchair in its one-piece frame construction is extremely compact and stiff and very light. If necessary, a self-reinforced design with additional ribs and reinforcing elements in or below the plastic body can be selected.

The required stiffness and hardness can be achieved by appropriate selection of the plastic. When using rigid foam material, certain desired parts of the wheelchair can also be additionally configured with soft foam parts. For this purpose, for example, the backrest 1, the seat 3, the armrests 7 and the upper edge 11 of the side walls 5 in the transition area from the armrests 7 to the footrest 9 come into question. Likewise, a circumferential bumper 13 made of soft foam material can also be provided on the underside of the footrest.

Viewed in cross section, the wheelchair is designed in a shell construction, the backrest also being U-shaped in cross section. At the top, push handles 15 are provided in the backrest, which at the same time can also serve as insertion openings for an attachable, extended headrest. Likewise, of course, the backrest 1 can also be pulled higher than shown in FIG. 1 in order to simultaneously serve as a headrest.

The rear space behind the backrest 1 and the space below the seat 3 can be used as storage space, for which purpose a further floor provided underneath the seat 3 and not shown in FIG. 1 can be provided or designed to be insertable.

As shown in Figure 3, the rear wheels 17 consist of a plastic solid body, which is preferably also made of foamed plastic. The handrail 19 and the tires 21 are part of the full wheel. The use of the foamed plastic material not only results in smooth operation, but above all an optimal shock absorption through the appropriate choice of material. Hard and soft foam materials can also be used simultaneously in the manufacture of the wheel. In FIG. 3 it is shown that, for example, at least the handrail 19 and the tires 21 designed here as flat tires can consist of soft foam material compared to the rest of the wheel body.

Of course, at least the entire outside can also be made of soft foam material, as a result of which the side security function can be further improved.

A bearing 23 is cast or foamed in the wheel during the manufacturing process and is attached and secured via a bearing pin 24 to a substructure 25 of the wheelchair. The base 25 is an integral part of the entire wheelchair, so that no further assembly work is necessary here.

In a departure from the exemplary embodiment shown, the handrail 19 can sit on the outer circumference of a disc body which is separate from the rest of the full wheel, in order to actuate a shift hub provided on the axis of rotation of the wheel. Such a shift hub can, for example, enable a translation into smaller parts, which means that older and weaker people can also drive the wheelchair on slight inclines.

4, in which the integrated brake 27 is shown schematically.

The brake 27 comprises a conventional brake linkage 29, the parking brake being effected by actuating a brake lever 31 which is an integral part of the armrest 7. At the end of the brake lever 31 opposite the arm lever, the brake pad 33 has advanced which acts on the tread of the wheel 17. Not only a non-positive, but also a positive braking effect is possible if, for example, the tread of the wheel 17 and the brake block 33 is provided with protruding and interlocking knobs. The parking brake can still be secured by actuating a further locking member 35.

Finally, it should be noted that at least one, preferably two, rotatable front wheels 37 are provided below or behind the footrest 9, which are rotatably held in the usual manner via an axle 39 and are attached in a trailing manner.

A wheelchair in accordance with the exemplary embodiment explained above can have a weight of only a maximum of 12 to 16 kg for foamed or 3 to 6 kg, in particular for fiber-reinforced plastics.

As can be seen from FIG. 3, the substructure 25 can also be produced as a separate component and subsequently connected to the back-seat part. Possible types of attachment come in addition to soluble attachments such. B. gluing, welding, etc. in question.

A further exemplary embodiment of a wheelchair according to the invention is shown schematically in FIG. 5, in which the front wheels 37 represent the load-bearing wheels. Here, too, the armrest is designed such that the tire is covered or covered in an at least upper area. Here, too, the handrail 19 can be provided on the wheel 17 as an integral part. In this embodiment, a conventional tire is used as the tread (FIG. 6).

An upper bracket 41 can be folded down and can thus serve as a headrest and handle. The rear third wheel is rotatably supported, wherein an electric motor can be installed at least as a supportive drive. For this purpose, a battery 43 can be attached to the underside of the wheelchair. Here, too, the actuating element for the brake can be integrated into the armrest.

As shown in FIG. 7 in a schematic side view, the wheelchair can also be provided with a transparent rain hood 45, which in the exemplary embodiment shown is almost egg-shaped in side view. The rain hood can be raised by an upper axis 47 in the area of the armrest. The rain cover can be removed.

As can be seen from the explanations of the exemplary embodiments, the wheelchair can consist of various plastic materials, for example thermoplastics, thermosets and / or elastomers. Certain advantages can be achieved especially in the processing of different materials. Both the thermoplastics, the thermosets or the elastomers can also be fiber-reinforced, as a result of which allow particularly stable and lightweight constructions. The foamed plastic can also be foamed largely easily on other plastic materials. If necessary, adhesion promoters can also be used. The desired sandwich construction can be achieved in this way. Due to the use of foamed materials, any necessary support and support skeletons can be easily defoamed, for example to achieve a desired stiffness even when using soft foam materials.

A lowering device 43 is explained in FIGS. 8 and 9 and is adjustable against the pressure force of a spring 45. By releasing a locking device 47, the spring 45 can be adjusted by shifting the weight forward so that the wheelchair with its footrest 9 lowers to the floor. In this position, the locking device 47 can be locked so that the footrest remains on the floor even when no one is in a wheelchair. After sitting down again on the wheelchair and after releasing the locking device, the footrest is automatically raised again, and in the raised position the locking device can be locked again, for example, by pressing an actuation button 49 into a corresponding hole. The mechanism can also be supported or operated electrically via a motor. The pressure element 45 acts on the front wheel 37, which is guided in a bushing, so that the lowering device 43 also represents a height adjustment device for the front wheel. A gas pressure spring or other spring devices for the spring 45 can also be installed.

Claims (20)

1. A wheel chair comprising a seat surface (3), a back rest (1) and a lower structure (25) for carrying the wheels (17 and 37) with a support frame consisting of synthetic resin, characterized in that the support frame, which consists of the seat surface (3), the back rest (1) and side walls (5), is manufactured in a single piece shell construction in order to provide a self-supporting design, which support frame consists of foam synthetic resin, which is possibly reinforced and in that furthermore the lower structure (25), which is carried on the wheels (17 and 37) consists of foam synthetic resin which is possibly reinforced.

2. The wheel chair as claimed in claim 1, characterized in that the side frame parts (5) are drawn up as far as the arm rests (7), which also consist of synthetic resin, which is preferably foam synthetic resin.

3. The wheel chair as claimed in claim 1 or in claim 2, characterized in that the entire support frame is manufactured integrally with the seat surface (3), the back rest (1) and the side walls (5) including the lower structure (25) and preferably with the arm rests (7).

4. The wheel chair as claimed in any one of the preceding claims 1 through 3, characterized in that the side walls (5) and/or the seat surface (3) extend through as far as their lower foot support (9).

5. The wheel chair as claimed in any one of the preceding claims 1 through 4, characterized in that adjacent to the foot support (9) a surrounding integrated shock absorber (13) is provided which preferably consists of foam synthetic resin.

6. The wheel chair as claimed in any one of the preceding claims 1 through 5, characterized in that the wheel chair preferably consists of hard foam synthetic resin and at least the upper side of the arm rest (7), the seat surface (3) and/or the back rest (1) consist of a soft foam synthetic resin which is more elastic than the same.

7. The wheel chair as claimed in any one of the preceding claims 1 through 6, characterized in that the tread of the wheels (17) is covered over in an upper part of the periphery by the side frame parts (5) and/or the arm rests (7).

8. The wheel chair as claimed in any one of the preceding claims 1 through 7, characterized in that the rear and/or front wheels (17 and 37) as well consist of foam synthetic resin.

9. The wheel chair as claimed in any one of the preceding claims 1 through 8, characterized in that the entire wheel (17 and 37) including the ground engaging tread consists of foam synthetic resin.

10. The wheel chair as claimed in any one of the preceding claims 1 through 9, characterized in that at least the tread consists of foam synthetic resin.

11. The wheel chair as claimed in any one of the preceding claims 1 through 10, characterized in that the wheel body is constituted by a solid wheel with an integrated handle rail (19) in one piece.

12. The wheel chair as claimed in any one of the preceding claims 1 through 11, characterized in that the wheel (17 and 37) comprises a wheel member of preferably hard foam synthetic resin and comprises a tread of soft foam synthetic resin.

13. The wheel chair as claimed in any one of the preceding claims 1 through 12, characterized in that the handle rail (19) arranged in an integrated manner on the rear wheel (17) consists of soft foam synthetic resin.

14. The wheel chair as claimed in any one of the preceding claims 1 through 13, characterized in that the rotary bearing (23) for the rear wheel (17) is held in the wheel member or, respectively, in the lower structure (25) of synthetic resin material during casting in a mold.

15. The wheel chair as claimed in any one of the preceding claims 1 through 14, characterized in that the actuating elements (31) for a brake (27) are arranged in the arm rest (7) in an integrated manner.

16. The wheel chair as claimed in any one of the preceding claims 1 through 15, characterized in that the parts consisting of soft foam and hard foam are connected together by interlocking means.

17. The wheel chair as claimed in any one of the preceding claims 1 through 16, characterized in that same is provided with a removable or folding rain protection hood of transparent synthetic resin material.

18. The wheel chair as claimed in claim 17, characterized in that the rain protection hood is adapted to be pivoted about a horizontal axis, preferably adjacent to the back rest.

19. The wheel chair as claimed in any one of the preceding claims 1 through 18, characterized in that the seat rest (1) comprises sections (79 and 81) which are able to be adjusted vertically and are able to be extended or, respectively, are able to be drawn out.

20. The wheel chair as claimed in any one of the preceding claims 1 through 19, characterized in that a lockable lowering device (43) is provided for the foot rest (9) by means of which the same is able to be lowered and lifted, preferably against a thrust force and in that a locking device (47) is provided for locking the lowering device (43) both in the lower standing position and also in the raised traveling position.

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