DRIVE DEVICE FOR A WHEELCHAIR

Description

Technical field

[0001] The present invention falls within the field of drive devices for personal means of transport, which are particularly designed for sick or disabled persons, such as wheelchairs and the like. According to the preamble of claim 1, the invention relates to a drive device for a wheelchair, comprising a control element, a chassis, and a support frame, wherein a fixing device is mounted on the support frame and can be fixed to a wheelchair frame of the wheelchair. State of the art

[0002] Drive devices for wheelchairs are known in numerous designs, and a fundamental distinction can be made between drive devices permanently attached to the wheelchair and detachable drive devices. All detachable drive devices have in common that they are only attached to a wheelchair when needed, and otherwise the wheelchair is essentially free of the usually bulky and heavy structural or drive elements required for manual operation.

[0003] From WO 2017 / 081475 A1, a drive device for a wheelchair is known in which, on the one hand, a hook engages a footrest of the wheelchair and, on the other hand, two support arms are connected to frame tubes of the wheelchair in such a way that the drive device is attached to the wheelchair by means of gravity.

[0004] Document WO 2015 / 040507 A2 discloses a drive device for a wheelchair, which has a handlebar and associated fork blades, between which a drive wheel with a motor is arranged, which can be powered by a power supply. The drive device has a clamping device on a clamping strut, which can be clamped to a frame tube of the wheelchair. The clamping device presented here has two clamping segments which, in a closed position, interlock via a locking lug on one clamping segment and a hook on the other clamping segment, and this clamping device can be fixed in this closed position by means of a hand-operated lever.

[0005] This established state of the art is characterized by the necessity of manually attaching or mounting the drive units to the wheelchair, which requires a certain degree of dexterity and mobility. Although these conventional drive units can be conveniently mounted on a wheelchair for relatively highly mobile individuals, the dexterity and mobility required for mounting and dismounting can exceed the capabilities of a wheelchair user. Consequently, such drive units cannot be used independently by the user, thus limiting their autonomy and potentially making assistance from another person essential for mounting and dismounting.

[0006] It is therefore an object of the present invention to propose a drive device for a wheelchair which enables independent and easy assembly or disassembly on a conventional wheelchair. Description of the invention

[0007] The problem is solved according to the invention by a drive device as defined in independent claim 1. Advantageous embodiments of the invention are set forth in the dependent claims.

[0008] The essence of the invention is as follows: A drive device for a wheelchair comprises a control element, a chassis, and a support frame. A fixing device is mounted on the support frame and can be attached to the wheelchair frame. The fixing device is designed to be automatically connected to and detached from the wheelchair frame via a fixing drive. The drive device can be a pulling device that is pre-tensioned to the wheelchair by means of the fixing device for pulling purposes. Alternatively, it can be a pushing device that is mounted on the rear of the wheelchair.

[0009] The term "chassis" refers to the parts of the drive system that provide a movable connection to a surface or roadway. The chassis can include a fork or wheel suspension and a drive wheel attached to it, a track system, or a similar device.

[0010] In the context of the invention, the term "automatic" refers in particular to connecting and disconnecting without the need for manual manipulation. The fixing process itself can therefore be carried out without manual intervention. However, triggering or stopping the fixing drive / fixing process can still be done manually, without this compromising the automatic connection or disconnection. For example, the drive device can be automatically connected to the wheelchair by correctly positioning it on the wheelchair, manually actuating a switch, thereby starting the fixing drive, and the fixing device then securing the wheelchair frame without any further manual intervention.

[0011] The fixing device can be designed in various ways, for example as a hook-in construction or as a clamping device. As a clamping device, it can be clamped to a tube or similar part of the wheelchair frame.

[0012] According to the invention, the fixing drive connects the fixing device and thus the drive unit to the wheelchair, eliminating the need for the wheelchair user to lean forward or even manually operate a locking device. The fixing device with fixing drive according to the invention significantly increases the user's independence and freedom of movement, as assistance from another person is no longer required. The fixing device according to the invention can also be advantageous for more mobile users, as it allows for convenient and safe installation and removal from the wheelchair.

[0013] Another advantage of the invention is that the present automatic fixing device provides a wide range of options for different frame tube thicknesses and does not require any proprietary adjustments between the drive device and the wheelchair.

[0014] Furthermore, an advantage is that no additional component is required to connect the drive unit to the wheelchair. Instead, the fixing device, according to the invention, acts directly on the wheelchair frame. This allows the wheelchair to remain maneuverable and lightweight when the drive unit is not connected to it.

[0015] The chassis can be operated in various ways. In one possible embodiment, it can be operated via hand pedals, which are connected to the chassis or a drive wheel thereof, for example, by a chain. Preferably, however, the drive device also includes a motor and a power supply, wherein the motor is powered by the power supply and connected to the chassis. Such a motor enables convenient automatic propulsion of the wheelchair. In combination with the aforementioned hand pedals, the drive device can be designed analogously to an e-bike. Such e-bike-like drive devices can enable combined automatic and (semi-)manual operation.

[0016] Preferably, the fixing drive includes a fixing motor. The fixing motor can be, in particular, a closing motor or a clamping motor. It can be designed as a linear motor. Such a fixing motor enables efficient, convenient, and safe operation of the fixing drive. The fixing motor is preferably designed to be powered from the power supply. In this way, the power supply, such as a battery for the motor or drive motor, can also be used for the fixing motor during assembly and disassembly. Because batteries are typically relatively heavy components of drive devices, this eliminates the need for additional batteries or power supplies to drive the fixing motor, thus keeping the weight of the drive device relatively low.

[0017] In an advantageous embodiment of the invention, the drive device comprises a switching element connected to the locking drive. The switching element can be designed as a push button, a knob, a switch, or similar. It can also be, for example, a piezoelectric component that can be activated without physical contact. The switching element can be used to actuate, or switch on and / or off, the locking drive. For this purpose, the switching element is advantageously located within easy reach of the wheelchair user, for example, on the handlebars, and thus readily accessible.

[0018] Preferably, the fixing device comprises a first and a second clamping jaw, which are connected to the fixing drive and to each other on one side via a joint. The fixing drive is preferably arranged around the joint to move the first and second clamping jaws relative to each other. By means of such clamping jaws, the fixing device can advantageously be designed as a clamping mechanism. This enables secure and efficient fixing of the drive unit to the wheelchair frame. In particular, different tube thicknesses or tube shapes can be fixed using the same clamping jaws, so that the drive unit can be automatically fixed to different wheelchairs.

[0019] Preferably, the drive device includes a contact element connected to the fixing drive and arranged so that it can be activated by the wheelchair frame when the frame is positioned as intended. The term "positioned as intended" in relation to the wheelchair frame can refer to its being arranged in a position suitable for connection to the drive device. The contact element enables the fixing device or fixing drive to be automatically triggered simply by the wheelchair being positioned appropriately. The contact element can be designed as a push button, a knob, a switch, or similar. It can also be, for example, a piezoelectric component that can be activated without physical contact.In a version of the fixing device with clamping jaws, the contact element is preferably a switching pin arranged between the clamping jaws, which can be brought into operative contact with the wheelchair frame when the drive unit is attached to the wheelchair. This allows for particularly simple assembly between the wheelchair and the drive unit. To release the drive unit, the switching element can then be actuated, for example, and the fixing device opens, releasing the wheelchair.

[0020] Preferably, the clamping device comprises a control unit or regulator connected to the clamping drive, wherein the regulator stops the clamping drive when the clamping pressure between the clamping jaws and the wheelchair frame reaches a predefined value and / or the closing of the clamping jaws does not continue for a predefined period. In the context of the clamping jaws closing, "does not continue" means that the closing movement has stopped, which can occur, for example, when the clamping jaws come into contact with a part of the wheelchair frame. With the aforementioned regulator, the clamping jaws can, for example, clamp a frame tube and stop the increasing clamping as soon as the motor's force is insufficient to further compress the clamping jaws or reaches a certain clamping pressure.This allows, among other things, frame tubes of different diameters or shapes to be securely connected using the same clamping jaws or fixing device. It also ensures that sufficient clamping force can be applied to securely fix a frame tube.

[0021] Each of the two clamping jaws preferably has essentially two straight clamping jaw segments and, between these straight clamping jaw segments, a connecting, angled clamping jaw segment for the purpose of unambiguous positioning of the wheelchair frame between the clamping jaws. The term "angled" in this context can refer to a kinked, curved, bent, or similar shape. This design of the clamping jaws ensures that the frame tube is always positioned near the curved clamping jaw segment during the closing process and is always aligned with the clamping jaws.

[0022] Preferably, the fixing device is designed such that the wheelchair frame is automatically lifted when the drive unit is connected. In particular, this lifting can refer to the area of ​​the wheelchair where its front wheels are mounted. Such lifting can, for example, be between approximately 2 cm and approximately 8 cm. This allows the front wheels of the wheelchair to be lifted off the ground. The entire assembly then rests on the rear wheels of the wheelchair and the chassis of the drive unit. This allows the wheelchair to have the necessary clearance at the front wheels, enabling efficient wheelchair maneuverability.

[0023] The support frame can consist of a tubular structure and a base. The base can be connected to the chassis, for example, via a tilting or rotating connection. Preferably, the support frame has a stand section that can be placed on a surface when the drive unit is not connected to the wheelchair frame. The support frame is also advantageously height-adjustable. This allows the drive unit to be adjusted to the user.

[0024] The chassis is preferably articulated to the support frame, allowing the distance between the chassis and the support frame to be adjusted. By changing this distance, and with a drive unit attached to the wheelchair, the distance between the chassis / drive wheel and the wheelchair / rear wheels can simultaneously be altered. This allows the wheelchair to be lifted efficiently. The distance can be changed, for example, by moving the chassis slightly towards the wheelchair. For instance, a drive wheel can roll backward a short distance while the wheelchair's rear wheels are locked.

[0025] The mounting frame is preferably equipped with a blocking structure with which the chassis can be blocked in several blocking positions relative to the mounting frame, wherein the distance between the chassis and the mounting frame is different in the several blocking positions.

[0026] Preferably, the fixing device comprises a pulling element and a pre-tensioning device designed to pull the chassis towards the wheelchair after the fixing device has connected the wheelchair frame. Such a design enables a relatively simple and safe automatic lifting of the wheelchair frame or wheelchair.

[0027] In a preferred embodiment, the fixing device is designed to be connectable to a front section of the wheelchair frame. The front section of the wheelchair frame is understood to be the area facing or forming the front of the wheelchair. Typically, the front section of the wheelchair frame is designed to accommodate or support the feet and lower legs of a user. The front section of the wheelchair frame can comprise one or more quasi-vertical or slightly inclined front frame tubes. In use, the front frame tubes can run more or less along the lower legs of the user. Such a design of the fixing device enables simple and efficient connection of the drive unit to the wheelchair.

[0028] According to the invention, the fixing device is designed to be connectable to a frame tube of the wheelchair frame. This frame tube can, in particular, be one of the two aforementioned front frame tubes. In other words, the frame tube of the wheelchair frame is preferably a quasi-upright front frame tube. The term "quasi-upright" can be understood as a precisely, more or less, or essentially vertical orientation of the front frame tube. In this way, the drive device can be efficiently mounted on the front of the wheelchair and thus used as a towing device.

[0029] The drive unit is designed to be positioned in front of the wheelchair when the fixing device is attached to the wheelchair frame. In this way, the drive unit can be designed as a traction device, enabling efficient and safe propulsion of the wheelchair.

[0030] For example, by predefined positioning of the front frame tube in the clamping jaws, a tube axis belonging to the front frame tube can, when the drive unit is mounted, form a first angle relative to a drivable surface. This first angle is smaller than a second angle when the drive unit is unmounted. This allows the front frame tube, and with it a corresponding section of the wheelchair frame, to be raised, thereby lifting the front wheels of the wheelchair off the ground and improving the driving characteristics of the powered wheelchair, which then only rests on the drivable surface with its rear wheels and chassis.

[0031] To lift the front wheels of the wheelchair, which are typically fixed to the frame tube, the drive unit can be equipped with a separate device – in addition to the aforementioned clamping jaw design or the aforementioned design with an articulated chassis. For example, the front frame tube or the front wheels can be lifted using a manual lifting device. Such a manual lifting device could, for example, include a pull rod or cable attached to the drive unit, which is pulled after the drive unit is connected to the wheelchair and then attached or hooked onto the wheelchair. Brief description of the drawings

[0032] The invention is explained below by way of example with reference to the figures. Identical objects in the figures are generally designated with the same reference numerals. It should be noted here that the figures have no limiting effect on the subject matter of the invention, but merely represent possible embodiments of the inventive concept. They show: Fig. 1 shows a drive device according to the invention for a wheelchair; and Fig. 2a shows a clamping device as an embodiment of a fixing device for the drive device. Fig. 1 in an open and a closed state. Ways to carry out the invention

[0033] Certain terms are used in the following description for practical reasons and are not to be understood restrictively. The words "right," "left," "below," and "above" denote directions in the drawing to which reference is made. The terms "inward," "outward," "below," "above," "left," "right," or similar are used to describe the arrangement of designated parts relative to one another, the movement of designated parts relative to one another, and the directions toward or away from the geometric center of the invention and of designated parts thereof, as shown in the figures. These spatial relative terms also include positions and orientations other than those shown in the figures. For example, if a part shown in the figures is turned upside down, elements or features described as "below" are then "above."The terminology includes the words explicitly mentioned above, derivatives of the same, and words of similar meaning.

[0034] To avoid repetition in the figures and the accompanying descriptions of the various aspects and embodiments, certain features should be understood as common to different aspects and embodiments. The omission of an aspect in the description or a figure does not imply that this aspect is missing in the corresponding embodiment. Rather, such an omission may serve to improve clarity and prevent repetition. In this context, the following rule applies to the entire subsequent description: If a figure contains reference symbols for the purpose of graphical clarity, but these are not mentioned in the immediately associated descriptive text, reference is made to their explanation in preceding figure descriptions.If, in addition, the descriptive text directly pertaining to a figure mentions reference symbols that are not included in the figure itself, reference is made to the preceding and following figures. Similar reference symbols in two or more figures represent similar or identical elements.

[0035] Fig. 1 Figure 1 shows a drive device 1 according to the invention, as it is mounted on a conventional wheelchair 2 by means of a clamping device 19 as a fixing device on the front frame tubes 71 of a wheelchair frame 7 of the wheelchair 2, without any components being permanently attached to the wheelchair frame 71. At their lower ends, the front frame tubes 71 are connected to each other via a footrest 6. Two small front wheels 5 are arranged on the underside of the footrest 6. A seat 3 is fixedly mounted on the wheelchair frame 7. The wheelchair 2 includes two large rear wheels 4, which are rotatably mounted on the wheelchair frame 7.

[0036] The drive device 1 comprises a handlebar 23 and an associated chassis, which includes fork legs 9 connected to the handlebar 23 and a drive wheel 13 mounted between the fork legs 9. A drive motor 12 is arranged in the hub of the drive wheel and is powered by a battery 8.

[0037] Furthermore, the drive device 1 has a mounting frame 15 equipped with the clamping device 19. The mounting frame 15 comprises a quasi-U-shaped base 24, the lower ends of which form a stand section 241. When disassembled, the two ends of the base 24 of the mounting frame 15 rest on a surface 22. This allows the mounting frame 15 to serve as a stand for the drive device 1 when it is detached from the wheelchair 2.

[0038] The support frame 15 further comprises a block 25, which is fixedly connected to a cross member of the base 24, and to which a control joint 26 is articulated. The control joint 26 is rotatably or tiltably connected to the block 25 at the top and to a locking structure via a linkage 27 at the bottom. The linkage 27 can be locked into various longitudinal positions on the block 25. This allows different angles of rotation between the control joint 26 and the block 25 to be fixed in the various positions. In this way, a distance between the drive wheel 13 and the support frame 15 can be adjusted. In particular, by reducing this angle, the drive wheel 13 can be pulled closer to the support frame, thus lifting the front wheels 241 of the wheelchair 2 off the ground 22.

[0039] In the Fig. 2a and 2bThe clamping device 19 is shown in more detail. In particular, it has two pairs of clamping jaws 19a, 19b, each connected to a clamping drive 21 as a fixing drive, wherein in the Fig. 2a and 2b For clarity, only one pair of clamping jaws 19a, 19b of the clamping device 19 are shown as an example, one in an open state and the other in a closed state. The clamping drives 21 each comprise a clamping motor 211, both of which are also powered by the energy supply 8 and actuated or activated by a push button located on the handle 23. Alternatively, a single clamping motor 211 could be provided to move both pairs of clamping jaws 19a,b.

[0040] The clamping jaws 19a,b are connected to each other at one end via a clamping joint 20. As shown in Fig. 1The clamping motor 211 is visibly arranged on a strut 16 of the mounting frame 15. Similar to an angle iron, the clamping jaws 19a,b have three clamping jaw segments 24a,b,c. Specifically, these are two straight clamping jaw segments 24a,c, which are connected to each other via a bent clamping jaw segment 24b.

[0041] To connect the drive unit 1 to the wheelchair 2, a user of the wheelchair 2 moves towards the drive unit 1 until the two front frame tubes 71 are positioned between the two clamping jaws 19a, 19b of a pair. By pressing the button, the clamping motors 211 move the clamping jaws 19a, 19b of the clamping device 19 towards each other, so that they securely fix the two front frame tubes 71.

[0042] When the drive device 1 is fed to the frame tube 7 with the clamping jaws 19a,b open, see Fig. 2aThe button can be pressed, which activates the clamping drive 21 or the clamping motor 211. The clamping motor 211 then retracts a spindle 18 mounted on the clamping jaws 19a,b, causing the clamping jaws 19a,b to move towards each other. The clamping drive 21 is equipped with a controller designed to stop the movement of the clamping jaws 19a,b if no movement occurs for a predefined period. In this state, the clamping jaws 19a,b are held in place, and the front frame tube 71 is firmly clamped and fixed, see [reference]. Fig. 2b .

[0043] Although the invention is illustrated and described in detail by means of the figures and the accompanying description, this illustration and detailed description are to be understood as illustrative and exemplary and not as limiting the invention. In order not to overstate the invention, well-known structures and techniques may not be shown and described in detail in certain cases. It is understood that those skilled in the art may make modifications and adaptations without departing from the scope of the following claims.

[0044] The disclosure includes embodiments that comprise exclusively the features described in the claims, as well as those that include additional other features.

[0045] Furthermore, the expression "comprise" and derivatives thereof do not exclude other elements or steps. Likewise, the indefinite article "a" and "an" and derivatives thereof do not exclude a plurality. The functions of several features listed in the claims can be fulfilled by a single unit or step. The terms "essentially," "about," "approximately," "quasi," and the like, when used in conjunction with a property or value, also define precisely that property or value. The terms "about," "quasi," and "approximately" in connection with a given numerical value or range can refer to a value or range that lies within 20%, within 10%, within 5%, or within 2% of the given value or range.

Claims

1. A pulling device (1) for a wheelchair (2), comprising a control element (23), a chassis (9, 13) and a support frame (15), wherein a fixing arrangement (19) is mounted on the support frame (15), which fixing arrangement (19) is fixable to a wheelchair frame (7) of the wheelchair (2), and wherein the pulling device is configured to be positioned in front of the wheelchair (2) when the fixing arrangement (19) is fixed to the wheelchair frame (7) of the wheelchair (2), and for pulling the wheelchair to be pretensioned to the wheelchair frame (7) by the fixing arrangement, characterized in that the fixing arrangement (19) is arranged to be automatically connected to and released from the wheelchair frame (7) of the wheelchair (2) by a fixing drive (21), wherein the fixing arrangement (19) is arranged to be connected to a frame tube (71) of the wheelchair frame (7) of the wheelchair (2).

2. The pulling device according to claim 1, which comprises a drive motor (12) and a power supply (8), wherein the drive motor (12) can be fed from the power supply (8) and is connected to the chassis (9, 13).

3. The pulling device (1) according to claim 1 or 2, in which the fixing drive (21) has a fixing motor (211), wherein the fixing motor (211) preferably is configured to be fed by the power supply (8).

4. The pulling device (1) according to any one of the preceding claims, which has a switching element (16) connected to the fixing drive (21).

5. The pulling device (1) according to any one of the preceding claims, in which the fixing arrangement (19) comprises a first and a second clamping jaw (19a,b), which are connected to the fixing drive (21) and to one another on one side via a joint (20), wherein the fixing drive (21) preferably is arranged around the joint (20) for moving the first and second clamping jaws (19a,b) towards each other.

6. The pulling device (1) according to any one of the preceding claims, which has a contact element connected to the fixing drive (21) and is arranged to be activatable by the wheelchair frame (7) when the same is positioned as intended.

7. The pulling device (1) according to claim 5 and 6, wherein the contact element is a switching pin (18) which is arranged between the clamping jaws (19a,b) and which can be brought into operative connection with the wheelchair frame (7) of the wheelchair (2) when attaching the drive device (1) to the wheelchair (2).

8. The pulling device (1) according to any one of claims 5 to 7, in which the fixing arrangement comprises a controller which is connected to the fixing drive, wherein the controller stops the fixing drive (21) when a clamping pressure between the clamping jaws (19a,b) and the wheelchair frame (7) reaches a predefined value and / or the closing of the clamping jaws (19a,b) does not continue for a predefined period of time.

9. The pulling device (1) according to any one of claims 5 or 6, wherein each clamping jaw (19a,b) substantially comprises two straight clamping jaw segments (24a,c) and, between these straight clamping jaw segments (24a,c), a connecting, angled clamping jaw segment (24b) for the purpose of distinct positioning of the wheelchair frame (7) between the clamping jaws (19a,b).

10. The pulling device (1) according to any one of the preceding claims, in which the support frame (15) has a stand portion (241) which can be placed on a ground surface (22) when the drive device (1) is not connected to the wheelchair frame (7) of the wheelchair (2), and / or is designed to be adjustable in height.

11. The pulling device (1) according to any one of the preceding claims, in which the fixing arrangement (19) is designed such that the wheelchair frame (7) of the wheelchair (2) is automatically lifted when connecting the drive device (1) .

12. The pulling device according to any one of the preceding claims, in which the chassis (9, 13) is hinged on the support frame (15) so that a distance between the chassis (9, 13) and the support frame (15) can be changed.

13. The pulling device according to the preceding claim, in which the support frame (15) is equipped with a blocking structure (27) with which the chassis (9, 13) can be blocked in a plurality of blocking positions relative to the support frame (15), wherein the distance between chassis (9, 13) and support frame (15) is different in the plurality of blocking positions.

14. The pulling device (1) according to claim 11 and 12 or 13, in which the fixing arrangement (19) comprises a pulling element and a pretensioning device which are designed to pull the chassis (9, 13) towards the wheelchair (2) after the fixing arrangement (19) has connected the wheelchair frame (7) of the wheelchair (2).

15. The pulling device according to any one of the preceding claims, in which the fixing arrangement is designed to be connected to a front region of the wheelchair frame (7) of the wheelchair (2).

16. The drive device according to any one of the preceding claims, in which the frame tube (71) of the wheelchair frame (7) of the wheelchair (2) is a quasi-upright front frame tube (71) of the wheelchair frame (7) of the wheelchair (2).