Wheelchair with electric platform

Abstract

The invention relates to a wheelchair for a person with reduced mobility, comprising a frame, a seat for the person supported by the frame, wheels arranged on the frame, a platform providing a standing surface for a second person, at least one coupling point on the frame where the frame and the platform are connected to each other, and at least one platform wheel arranged near the end of the platform furthest from the coupling point, wherein the platform is fixed to the frame by means of a releasable coupling, the platform wheel is designed as a drive wheel that can be driven by an electric motor, and the platform coupled to the frame is designed to move the wheelchair by means of its drive wheel.

Description

[0001] The invention relates to a wheelchair for a person with reduced mobility, comprising a frame, a seat for the person supported by the frame, wheels arranged on the frame, a platform providing a standing surface for a second person, at least one coupling point on the frame at which the frame and the platform are connected to each other, and at least one platform wheel arranged near the end of the platform furthest from the coupling point.

[0002] It is known from various publications, including DE 10 2017 127 568 B3 and EP 3 622 937 A1, to retrofit aids for people with reduced mobility, namely so-called rollators, with an electrically powered platform. This platform allows the rollator user not to have to walk, but to be moved forward by an electric motor while standing on the platform.

[0003] From US Patent 8,006,786 B1 and US Patent 4,096,920 A, it is known to equip electrically powered wheelchairs with a trailing platform, allowing companions of the wheelchair user to be transported by the wheelchair's electric motor without having to move themselves. This is advantageous in a variety of situations. For example, a wheelchair user with limited mobility may be accompanied by another person with similarly limited mobility. This is common in cohabiting couples when both partners are elderly. In such cases, the range of movement and thus the quality of life are significantly increased if the less restricted partner can conserve their energy by being transported on the platform.

[0004] German patent application DE 10 2007 062 406 A1 discloses a drive module that can be used for both wheelchairs and rollators. The function and construction of this drive module are explained using a rollator as an example. The drive module comprises a drive wheel with an integrated electric motor. The drive wheel is located under the rollator and can be lifted to disengage its drive function. This publication also proposes attaching a wheeled platform to the frame of the drive wheel, where it is mounted to the rollator. This platform enables the electric-powered rollator to transport a person.

[0005] The electric wheelchairs with trailing platforms described in the prior art have the significant disadvantage that the drive unit and energy storage system are located on the wheelchair itself. This further complicates the handling of the already rather heavy and bulky wheelchair, for example, when transporting it in a car. Since the drive typically acts on the large rear wheels of the wheelchair, a complex gearbox is required to ensure a suitable gear ratio. This further increases the weight of the wheelchair and its technical complexity.

[0006] Furthermore, an electric drive on the wheelchair is not necessary in all situations. For example, if the accompanying person has no mobility limitations, the electric drive and the trailing platform increase the wheelchair's weight and put a strain on the accompanying person or the wheelchair user.

[0007] Ultimately, the need for motorized assistance is usually not present from the outset, but arises later for the individuals concerned. In this case, new wheelchairs must be procured, which represents a significant cost factor for those affected and places a further burden on this already disadvantaged group.

[0008] Therefore, the purpose of the invention is to create a new concept for mobility support for wheelchair users.

[0009] The problem of the invention is solved by a wheelchair having the features of claim 1, in particular its characterizing features.

[0010] The key advantage of the invention lies in the fact that the powered platform can be easily detached from the wheelchair via its coupling, without the need for tools, and can be attached or detached as required. Therefore, if the platform is not needed, it does not have to be transported. This reduces the transport weight of the wheelchair.

[0011] Another advantage is that the wheelchair and the platform can be decoupled for transport purposes. This makes the wheelchair much easier to handle when the platform needs to be used.

[0012] It is also intended that the wheelchair has two coupling points spaced apart from each other in the direction of movement, with a first coupling point allowing the platform to be arranged behind the wheelchair and the second coupling point allowing the platform to be arranged under the wheelchair.

[0013] With a wheelchair designed in this way, it is not only possible to position the platform behind the wheelchair to transport an accompanying person. Alternatively, the platform can be positioned underneath the wheelchair – leaving the space behind the wheelchair free for an accompanying person who is not being transported but can assist the wheelchair user – and in this case, it can be used as a retrofittable auxiliary drive.

[0014] The contact pressure of the platform on the ground, necessary for propulsion, can be generated by a spring element or a gas pressure damper. Alternatively, the straight line running from the platform's wheel axle to the frame's coupling point can form an angle of 20 to 60 degrees, particularly 40 to 50 degrees, preferably approximately 45 degrees, with a horizontal line.

[0015] It is assumed that the frame has a scissor mechanism for folding the wheelchair and that at least one coupling point lies in a vertical plane spanned by the axis of the scissor mechanism.

[0016] The platform's arrangement according to the proposed design offers several advantages. Firstly, the platform attaches to the wheelchair frame in a physically advantageous position, namely centrally. This ensures that the propulsive forces are distributed evenly.

[0017] Furthermore, this arrangement allows the platform to be pivotable, with the pivot joint being formed via the coupling at the coupling point, so that at least one drive wheel of the platform can be rigidly designed and thus optimally provide its propulsion function.

[0018] Furthermore, the physical scissor axis in particular provides an optimal location for retrofitting the frame-side components of the coupling.

[0019] Furthermore, both with a trailing platform arrangement and a platform located under the wheelchair, the weight forces exerted on the wheelchair frame by the platform and, if applicable, the standing attendant, can be optimally directed, so that tipping of the wheelchair due to the additional weight is reliably avoided.

[0020] The invention also provides that the platform, in addition to at least one drive wheel, also provides the motor, the energy storage device and the control electronics.

[0021] In this way, the platform forms an essentially self-contained unit, independent of any technical equipment on the wheelchair. This has the significant advantage that the platform can be easily retrofitted to existing, non-electric or non-motorized wheelchairs as an additional drive or as an assistive transport solution for an attendant.

[0022] For handling the wheelchair, especially its transport, this solution has the distinct advantage that the weight required for the drive system and energy storage does not add any further burden to the wheelchair. This makes the wheelchair easy for one person to handle, particularly portable, and easy to move from one place to another when not in use.

[0023] To operate the platform, only a control unit for the control electronics needs to be retrofitted to the wheelchair itself. Whether this control unit is connected wirelessly or via cable, the effort required to equip an existing wheelchair with such a unit is manageable.

[0024] The aforementioned features of the invention therefore constitute the essential prerequisite for being able to retrofit existing wheelchairs without motorization in a particularly simple and technically uncomplicated way.

[0025] A better understanding of the invention will follow from the description of an exemplary embodiment below. The figures show: Fig. 1 a wheelchair according to the invention with an electrically driven platform in a perspective view from the front, Fig. 2 the wheelchair according to Fig. 1 in perspective view from behind, Fig. 3 the wheelchair after Fig. 1 without platform in side view, Fig. 4 the wheelchair according to Fig. 1 with a first arrangement of the platform on the wheelchair, Fig. 5 the wheelchair according to Fig. 1 and the representation according to Fig. 4 with platform in alternative arrangement on the wheelchair, Fig. 6 the platform according to Fig. 4 in individual presentation.

[0026] In the figures, a wheelchair according to the invention is provided with the reference numeral 10. The wheelchair 10 has a seat 11, which is primarily formed by a seat cover 12. The seat cover 12 is held by a frame 13. The frame 13 is shown only partially in the present drawings, in particular in the form of the handle tubes 14 and the scissor arms 15, which form a scissor joint 16 for folding or unfolding the wheelchair 10.

[0027] The remaining parts of frame 13 have not been shown for the sake of clarity.

[0028] The frame 13 holds, as is usual with wheelchairs, rear wheels 17 and front wheels 18, on which the wheelchair 10 can be moved.

[0029] Insofar as the wheelchair 10 according to the invention corresponds to what is known from the prior art.

[0030] The in Fig. 1 and Fig. However, the wheelchair 10 shown in perspective view is provided according to the invention with an electrically driven platform 19.

[0031] Fig. 3 shows the one in Fig. 1 and Fig. 2 wheelchairs 10 shown in side view, each from a different perspective. Platform 19 is in Fig. Figure 3 is not shown. Also shown here is the wheelchair 10 with the seat 11, the rear wheel 17, the front wheel 18, and the frame components. Particular attention should be paid to the scissor arms 15, on which a coupling assembly, designated by the reference numeral 20, is arranged. This assembly consists of a front coupling pin 21, which is pivotally mounted on a horizontal axis 22. The front coupling pin 21 is vertical in its neutral position and returns to this neutral position via a spring element operatively connected to the horizontal axis 22. The coupling assembly 20 also has a rear coupling pin 23, which is likewise vertically oriented and pivotally mounted on a horizontal axis 22, which is operatively connected to a spring element.Here too, the rear coupling pin 23 is located vertically in its neutral position, into which it is forced by the spring element of the horizontal axis 22.

[0032] The coupling assembly 20 has two retaining arms 24 that accommodate the scissor joint 16 between them. These arms support a front coupling frame 25 and a rear coupling frame 26, thus securely positioning the coupling assembly 20 on the frame 13 in the area of ​​the scissor joint 16. The front coupling frame 25 carries the front coupling pin 21. The rear coupling frame 26 carries the rear coupling pin 23.

[0033] The front coupling pin 21 and the rear coupling pin 23 each form a coupling point. The platform can be arranged – as described below – alternatively at the front coupling pin 21 or at the rear coupling pin 23 to realize their respective advantages.

[0034] Fig. Figure 6 shows the platform 19 on its own. The platform 19 has a chassis 27, which initially provides a standing surface 28 for one person. At its rear end, the chassis 27 has at least one drive wheel 29; in this specific embodiment, two drive wheels 29 are provided. The drive wheel 29 is driven by an electric motor, and the chassis 27 includes a storage compartment 30 for an energy storage device in the form of a battery and the control electronics. A connecting rod 31 is arranged at the front end of the chassis 27 opposite the drive wheel 29. This rod is fixed to the chassis 27 via a vertical axis (not visible) and allows rotation, preferably a 360-degree rotation.

[0035] At the free end, located away from the chassis 27, the connecting rod 31 is fitted with a coupling 32. Depending on the desired arrangement of the platform 19, this coupling 32 is placed on the front coupling pin 21 or the rear coupling pin 23.

[0036] Finally, the chassis 27 forms a handle 33, which greatly simplifies the handling of the platform 19, especially its transport.

[0037] In the example shown here, a control line 34 is connected to the coupling 32, by means of which an operating unit arranged on the frame 13, in particular on the handle tube 14, is connected to the platform 19 in order to control the drive and propulsion via the control electronics contained in the platform 19.

[0038] Fig. Figure 4 shows the wheelchair 10 according to the invention with the platform 19 in a first arrangement. In this arrangement, the platform 19 is positioned below the seat 11, essentially centered below the scissor joint 16. The coupling 32 is mounted on the front coupling pin 21 for this purpose. The connecting rod 31 is pivoted towards the rear drive wheels 29. The drive wheels 29 are positioned approximately below the pivot axis 35 of the rear wheel 17 of the wheelchair 10.

[0039] In this position, platform 19 is as in Fig. The platform 19, shown in Figure 4, is positioned under the wheelchair 10 and hooked into the front coupling pin 21, serving as a retrofittable electric drive. The platform is readily capable of electrically propelling the wheelchair and its user, or assisting the user in wheelchair movement in challenging situations, such as uphill travel. Simultaneously, the platform 19 can be detached from the wheelchair 10 at any time, allowing the wheelchair to be used even without the retrofitted electric drive. Furthermore, the wheelchair 10 and platform 19 can be transported separately, which is advantageous in terms of handling, particularly with regard to weight, but also in terms of compact dimensions during transport.

[0040] Fig. Figure 5 shows an alternative arrangement of the platform 19 on the wheelchair 10. Here, the coupling 32, arranged on the connecting rod 31, is engaged in the rear coupling pin 23. The connecting rod 31 is positioned differently from the illustration in Figure 5. Fig. 4 rotated 180 degrees forward. The platform 19 is not positioned below the wheelchair 10; instead, it follows the wheelchair 10. The rear coupling point, specifically the rear coupling pin 23, is located approximately at the level of the rear wheel axle 35, specifically slightly offset forward. This ensures excellent stability of the coupling 32 between the trailing platform 19 and the wheelchair 10.

[0041] The platform 19's support surface 28 is positioned so that, in addition to the wheelchair user, who sits on the seat 11, an accompanying person can stand on the platform 19, which follows the wheelchair 10. This additional person can not only support themselves on the handles 14, but also influence the direction of travel of the wheelchair 10 in the usual way using the handles 14. In this way, even an accompanying person with some physical limitations can accompany the wheelchair user on their journeys.

[0042] Here too, it is possible to completely dismantle platform 19 and use wheelchair 10 without platform 19. Likewise, the aforementioned transport advantages are realized with this second arrangement of platform 19 on wheelchair 10.

[0043] The invention thus achieves the goal of creating a wheelchair 10 that can be adapted to a wide variety of different needs. The wheelchair 10 according to the invention can be used without an electric motor drive and then has no weight or other limitations. It can easily be extended with the platform 19 to become an electrically powered or electrically assisted wheelchair 10. Furthermore, a wheelchair 10 with the platform 19 can also be provided that can transport not only the wheelchair user but also a companion with limited mobility. Reference symbol list 10 wheelchairs 11 Seating area 12 Seat cover 13 frame 14 Handle tube 15 scissor bars 16 Scissor joint 17 rear wheel 18" front wheel 19 Platform 20 coupling assembly 21 front coupling pin 22 Horizontal axis 23 rear coupling pin 24 Support arm 25 front coupling frame 26 rear coupling frame 27 chassis 28 Footprint 29 drive wheel 30 storage boxes 31 Connecting rod 32 Clutch 33 Handle 34 Control line 35 axis of rotation

Claims

[1] Wheelchair (10) for a person with reduced mobility, - with a frame (13), - with a seat supported by the frame (13) for the person, - with wheels (17, 18) arranged on the frame (13), - with a platform (19) that provides a standing area (28) for a second person, - with at least one coupling point on the frame (13) in which the frame (13) and the platform (19) are connected to each other, - with at least one platform wheel which is arranged near the end of the platform (19) furthest from the coupling point, wherein - the platform (19) is fixed to the frame (13) by means of a detachable coupling (32), characterized by , that - the platform wheel, which is arranged near the end of the platform (19) furthest from the coupling point, is designed as a drive wheel (29) which can be driven by an electric motor, - the platform (19) attached to the frame (13) is designed to move the wheelchair (10) by means of its drive wheel (29), - the wheelchair (10) has two coupling points spaced apart from each other in the direction of movement, wherein a first coupling point allows the platform (19) to be arranged behind the wheelchair (10) and the second coupling point allows the platform (19) to be arranged under the wheelchair (10). [2] Wheelchair according to claim 1, characterized by that the contact pressure of the platform on the ground, necessary for propulsion, is generated by a spring element or a gas pressure damper. [3] Wheelchair according to claim 1, characterized by, that the contact pressure of the platform on the ground necessary for propulsion is produced by an arrangement in which the straight line running from the wheel axle of the platform to the coupling point of the frame forms an angle of 20 degrees to 60 degrees, in particular 40 degrees to 50 degrees, preferably at approximately 45 degrees, with a horizontal line. [4] Wheelchair (10) according to claim 1, characterized by , that the frame (13) has a scissor mechanism for folding the wheelchair (10) and that at least one coupling point lies in a vertical plane spanned by the axis of the scissor mechanism. [5] Wheelchair (10) according to any one of the preceding claims, characterized by that the platform (19) provides, in addition to at least one drive wheel (29), the motor, the energy storage device and the control electronics.

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