DEVICE FOR A WHEELCHAIR

Abstract: The present invention relates to an arrangement (3) for a wheelchair wheel (4) which comprises a wheel rim (1) and a driving ring (2) either permanently or detachably attached to the wheel (4), in conjunction with which a tyre (5) is so arranged as to be detachably connected to the wheel rim (1), and the wheel (4) exhibits a frame (7) attached to the wheel rim (1). The wheel rim (1) and the driving ring (2) can be formed from a common profile ring (6), and the wheel rim (1) is detachably attachable to said wheel frame (7). In accordance with the invention, the wheel rim (1) comprises a number of separate, curved divergent spokes (13, 14) extending radially from a centrally located hub (11), which spokes are attached to the rim.

Description: Device for a wheelchair. 5 The present invention relates to an arrangement for a wheelchair wheel which comprises a wheel rim and a driving ring either permanently or detachably attached to the wheel, in conjunction with which a tyre is so arranged as to be detachably connected to the wheel rim, and the wheel exhibits 0 a frame attached to the wheel rim. Previously disclosed in the case of wheelchairs intended to be capable of being driven manually with the help of a driving ring arranged on each wheel is the principle of causing the driving ring and the wheel rim to be made from 5 separate parts that can be connected together. Said previously disclosed wheelchairs exhibit attachments for a driving ring in the form of bolts or other connections that are so arranged as to be capable of securing the driving ring to the wheel hub. These previously disclosed constructions 0 are compact and consist of many components, which are difficult to keep free from dirt when the wheelchair is being used out of doors. Their weight is also considerable, and the manufacturing process is complicated and determines the use of specific types of component parts. Said connections can 5 also end up in hazardous positions, in which they damage the wheelchair user, i.e. when the driving ring is being rotated. The construction is also weak and poses the risk of the wheels easily becoming distorted, especially when the wheelchair is used in difficult terrain, on stairs or against 0 kerbstones. The principal object of the present invention is thus, in the first instance, to make available an arrangement which, amongst other things, solves the aforementioned problems in a simple and effective manner. Said object is achieved by means of an arrangement in accordance with the present invention, which is characterized essentially in that the wheel rim and the driving ring are formed from a common profile ring or are detachably attached to one another, in that the wheel rim is detachably attachable to said wheel frame, in that the wheel rim comprises a number of separate rim central parts extending radially from a centrally located hub, which central parts extend in a direction from said hub towards the wheel rim, in that the respective rim central part is divided into two and is formed from diverging spokes arranged in pairs that are connected to one another at their outer ends via a connecting part, in that the spokes extend in a curved fashion, and in that the spoke connecting parts are riveted, screwed or connected in some other way to the inner peripheral part of the rim. The invention is described below with reference to the accompanying drawings, in which Fig. 1 shows a schematic side view of a wheelchair that is equipped with a wheel arrangement in accordance with the present invention; Fig. 2 shows a side view of a wheel with an arrangement in accordance with a first illustrative example; Fig. 3 shows a sectioned view of a part of said wheel arrangement viewed along the line III-III in Fig. 2; Fig. 4 shows a part of a wheel rim in accordance with the invention; Fig. 5 shows a cross-sectional view of a wheel rim profile; Fig. 5B shows a second example of a wheel profile; Figs. 6-11 show details of the second wheel profile example, in conjunction with which Fig. 6 shows a front view of the wheel profile; Figs. 7 and 8 show the wheel respectively from the front and from the inside; Fig. 9 shows the outside of the wheel; Fig. 10 shows a sectioned view along the line X-X in Fig. 9; Fig. 11 shows a perspective view of the wheel rim arrangement in accordance with the second example shown in detail above; and Fig. 12 shows a further illustrative embodiment of the invention. In accordance with the present invention, a wheel rim 1 and a driving ring 2 in an arrangement 3 for a wheelchair wheel 4, which comprises an aforementioned wheel rim 1 and a driving ring 2 that are permanently or detachably attached to the wheel 4, in conjunction with which a tyre 5 is so arranged as to be detachably connected to the wheel rim 1, are formed by a common profile ring 6. The wheel 4 also exhibits a frame 7, which is connected to the wheel rim 1, whereby the wheel rim 1 is detachably attachable to said wheel frame 7. The wheel profile ring 6 and preferably also the wheel frame 7 are appropriately made of aluminium or some other suitable metal. The wheel profile ring 6 is appropriately produced from an extruded profile that has been bent into a circular wheel form and has been joined together at the ends 6A, 6B by welding. Plastic material can also be used alone or in combination with metal material. Said wheel profile ring 6 is appropriately formed from a rim 1 exhibiting a U-shaped cross-sectional profile and a driving ring 2 exhibiting a ring-shaped cross-sectional profile and a connecting part 8 connecting them together. Said wheel profile ring 6 exhibits a hollow profile 9 in the base part 10 of the wheel rim 1. Amongst other things, this saves weight without impairing the strength. The driving ring 2 extends along the periphery of the wheel 4 with a diameter DI that is smaller than the diameter D2 of the wheel rim 1. Good transmission of force to the wheel 4 is still obtained in this way from the person sitting in the wheelchair and operating the driving ring 2 with his hands, but without the driving ring 2 making contact with the ground. In accordance with the illustrative example, the wheel rim 1 comprises a number of separate rim central parts 12 extending radially from a centrally located hub 11, which central parts extend in a direction away from said hub 11 towards the wheel rim 1. Each rim central part 12 is appropriately divided into two and is formed from diverging spokes 13, 14 arranged in pairs that are connected to one another at their outer ends 13A, 14A via a spoke connecting part 15 extending axially between them in a slightly curved fashion along the periphery of the rim. As shown in the first illustrative embodiment in accordance with Figs. 1-4 and 12, the spokes 13, 14 extend in a curved fashion, in conjunction with which five or more pairs of spokes are uniformly distributed around the periphery of the wheel rim 1. Said spoke connecting parts 15 are appropriately riveted or screwed to the inner peripheral part 1A of the rim 1 or are attached to the rim by means of other connecting devices 16. As can be appreciated from Figs. 6-11 in accordance with the second illustrative embodiment, the hub 11 is located on a central part 18 displaced axially from the common plane 17 of the central parts 12 of the rim, which central part is formed from the common inner assembled parts 19 of the central parts of the rim. The advantages of an arrangement 3 in accordance with the present invention should have emerged from the foregoing, although they may be briefly summarized in that a wheelchair wheel 4 executed with an integral driving ring 2 and wheel rim 1 is, amongst other things, easy to keep free from dirt and provides a more comfortable and secure grip than in the case of traditional attachments. Lower weight is also achieved, not to mention cost savings. Any colour is possible, and the more stable construction prevents distortion as before. It is also possible to adopt a new approach towards design, appearance, function and manufacture. A so-called quick-release or fixed axle is also obtained. Fig. 12 shows an example of a detachably attached driving ring 2, which is capable of attachment by means of fixing screws 50 and distance tubes 51 to the wheel frame 7, and more specifically is screwed through the respective radial spoke connecting part 15 on the outside of said wheel frame . The invention is not restricted to the illustrative examples described above and shown in the drawings, but may be varied within the scope of the patent claims without departing from the idea of invention.

Claims: P a t e n t C l a i m s 1. Arrangement (3) for a wheelchair wheel (4) which comprises a wheel rim (1) and a driving ring (2) either permanently or detachably attached to the wheel (4) , in conjunction with which a tyre (5) is so arranged as to be detachably connected to the wheel rim (1) , and the wheel (4) exhibits a frame (7) attached to the wheel rim (1), characterized in that the wheel rim (1) and the driving ring (2) are formed from a common profile ring (6) or are detachably attached to one another, in that the wheel rim (1) is detachably attachable to said wheel frame (7), in that the wheel rim (1) comprises a number of separate rim central parts (12) extending radially from a centrally located hub (11) , which central parts extend in a direction from said hub towards the wheel rim (1) , in that the respective rim central part (12) is divided into two and is formed from diverging spokes (13, 14) arranged in pairs that are connected to one another at their outer ends (13A, 14A) via a connecting part (15) , in that the spokes (13, 14) extend in a curved fashion, and in that the spoke connecting parts (15) are riveted, screwed or connected in some other way to the inner peripheral part (1A) of the rim. 2. Arrangement as claimed in Patent Claim 1, characterized in that the wheel profile ring (6) is made of aluminium or some other metal. 3. Arrangement as claimed in one or other of Patent Claims 1-2, characterized in that the wheel profile ring (6) is formed from a rim (1) exhibiting a U-shaped cross- sectional profile and a driving ring exhibiting a ring-shaped cross-sectional profile (and a connecting part (8) connecting them together) . 4. Arrangement as claimed in Patent Claim 3, characterized in that the wheel profile ring exhibits a hollow profile (9) in the base part (10) of the wheel rim (1) . 5. Arrangement as claimed in one or other of Patent Claims 3-4, characterized in that the driving ring (2) extends along the periphery of the wheel (4) with a diameter (DI) that is smaller than the diameter (D2) of the wheel rim (1) • 6. Arrangement as claimed in Patent Claim 1, characterized in that five or more pairs of spokes (13, 14) are uniformly distributed around the periphery of the wheel rim (1) . 7. Arrangement as claimed in Patent Claim 1, characterized in that the hub (11) is located on a central part (18) displaced axially from the common plane (17) of the rim central parts (12), which central part is formed from the common inner assembled parts (19) of the central parts of the rim.

Inventors: JACOBSON MAGNUS, JACOBSON, MAGNUS
Applicants: DESIGN KONSTRUKTIONER I BROARY, DESIGN KONSTRUKTIONER I BROARYD AB
Application year: 1998
Main classification: A61G5
IPC codes: A61G5