VEHICLE FOR USE ON STAIRS OR RAMP

Description

[0001] The invention relates to a vehicle for traveling up stairs or a ramp, wherein the vehicle has wheels, a crawler track, a support for carrying and transporting a load and a support wheel and can be operated selectively in one of the following operating modes: a first operating mode, which is provided for a substantially level surface, in which the one or more wheels are driven, a second operating mode, which is provided for traveling up stairs or a ramp, in which the crawler track is driven, a third operating mode in which the height of the support for carrying and transporting a load is adjustable and the vehicle is supported on the crawler track and the support wheel.

[0002] Document CN 111 297 582 A proposes a vehicle of this type.

[0003] Such a vehicle is also known, for example, from EP 3 598 959 A1, which originates from the applicant. The vehicle can be designed, in particular, as a wheelchair, which is particularly comfortable for a user. In the third operating mode mentioned above, the seat-shaped support can be moved forward so that the wheelchair can be moved under a tabletop.

[0004] The term "support wheel" used in this application is to be understood broadly and can include a hard rubber wheel, a pneumatic tire and, in principle, also a track of a crawler track.

[0005] To switch between the different operating modes, the crawler track and the support wheel(s) must be moved into specific positions. For this purpose, the vehicle according to the invention has at least one first linear motor for adjusting the crawler track and a second linear motor for adjusting the support wheel(s). If the vehicle has two support wheels, a linear motor can also be assigned to each support wheel.

[0006] However, it has been found that under certain conditions, linear motors are subjected to high loads. When the vehicle according to the invention is in the uppermost position in height adjustment mode, the force required by the linear motor to adjust the crawler track is at its maximum. On the other hand, the linear motor of the crawler track must exert a particularly high force even when the vehicle is in the forwardmost position in height adjustment mode. The linear motor of the crawler track is subjected almost exclusively to compressive loads, while the linear motor for adjusting the support wheel is subjected almost exclusively to tensile loads.

[0007] The invention is therefore based on the object of providing a vehicle for driving up stairs or a ramp in which both the linear motor of the crawler track and the linear motor of the support wheel are relieved of load.

[0008] To achieve this object, in a vehicle of the type mentioned at the outset, it is provided according to the invention that the vehicle has at least a first linear motor for adjusting the crawler track, a second linear motor for adjusting the support wheel, a lifting mechanism with a base body on which the first linear motor and the second linear motor are arranged, and a spring arranged on the lifting mechanism for relieving the first and / or the second linear motor.

[0009] The invention is based on the discovery that the first and / or second linear motor can be relieved of load by the spring arranged on the lifting mechanism. In this way, the operating range of the linear motors can be shifted to a more favorable range, so that they are not subjected to one-sided loading.

[0010] Within the scope of the invention, it is preferred that the first linear motor for adjusting the crawler track be relieved by a tensile force generated by the spring, which counteracts a compressive force acting on the first linear motor. The compressive force is primarily generated by the vehicle's own weight as well as the weight of an item or load located on the vehicle's support. The spring thus serves to compensate for the compressive force and relieves the first linear motor for adjusting the crawler track.

[0011] A preferred variant of the invention provides that the spring is designed as a compression spring and is arranged such that the second linear motor for adjusting the support wheel is relieved by a compressive force generated by the compression spring, which counteracts a tensile force acting on the second linear motor.

[0012] According to the invention, the lifting mechanism of the vehicle according to the invention comprises a base body on which the first linear motor and the spring are preferably arranged in an articulated manner. One end of the spring is thus attached to the base body, and the other end of the spring can be attached to a strut to which the support wheel or wheels are attached.

[0013] A further development of the invention provides that the vehicle has two parallel springs or compression springs. In this embodiment, the vehicle has two support wheels, each of which has one end of a spring attached, with the other end of the spring attached to the bracket. Alternatively, only a single support wheel can be provided.

[0014] Preferably, the spring can be designed as a gas spring, which generates a compressive force that serves to relieve the load on the first linear motor for adjusting the crawler track and / or the second linear motor for adjusting the support wheel(s). Furthermore, the gas spring has the advantage of dampening vibrations and possessing a flat spring characteristic, allowing a high compressive force to be generated even in the extended state. The gas spring can be mounted in such a way that, when the crawler track is driven, i.e., when driving up stairs or a ramp, a preload is generated that prevents rattling noises.

[0015] The vehicle according to the invention is particularly suitable for being operated in a self-balancing manner in the first operating mode by driving parallel wheels of an axle.

[0016] The vehicle according to the invention can be designed as a wheelchair with a holder designed as a seat. In In the third operating mode, the height of the seat can be adjusted vertically and longitudinally as required, for example when the person using the vehicle is at a table.

[0017] The invention is explained below using an exemplary embodiment with reference to the drawings. The drawings are schematic representations and show: Fig. 1 is a perspective view of a vehicle according to the invention designed as a wheelchair, Fig. 2 is a schematic side view of the vehicle according to the invention designed as a wheelchair in the first operating mode (driving mode), Fig. 3 is the Fig. 2 shown wheelchair in the second operating mode, when driving up stairs, Fig. 4 in Fig. 2 shown wheelchair in the third operating mode (height adjustment mode), in the upper position, Fig. 5 in Fig. 2 shown wheelchair in the third operating mode (height adjustment mode), in the lower position, Fig. 6, in Fig. 2 shown wheelchair in the parked state, and Fig. 7 the linear motors attached to the base body of the wheelchair.

[0018] The Fig. 1 The wheelchair 1 shown comprises a base body 2 provided with wheels 3, 4 on both sides. The wheelchair 1 has an electric drive (not shown in detail) by which the wheels 3, 4 can be driven. The wheels 3, 4 are used for driving on a substantially level surface in a first operating mode. In addition, the wheelchair 1 has a crawler chassis 5, which includes a belt or chain. By means of the crawler chassis 5, the wheelchair 1 is capable of negotiating stairs or a ramp. In In this second operating mode, the wheels 3, 4 are in a raised position. In the first operating mode, when the wheelchair 1 is moved by means of the wheels 3, 4, the crawler track 5 is in a raised position. Using a controller (not shown), the drive can be controlled so that the wheelchair carrying the user is supported and thus balanced solely by the wheels 3, 4. The wheelchair 1 is designed as a self-balancing vehicle.

[0019] Fig. 2 is a schematic side view of the vehicle configured as a wheelchair 1 in the first operating mode (drive mode). The wheelchair includes a seat 6. In this first operating mode, the wheelchair 1 is self-balancing, meaning only the two wheels 3, 4 touch the ground. Balancing is performed by the controller, which is connected to an inertial measurement unit (IMU) and controls the wheels 3, 4 based on sensor data.

[0020] The wheelchair 1 comprises a first linear motor 7, which serves to adjust the crawler track. One end of the first linear motor 7 is attached to the crawler track 5, the other end is attached to the base body 2. In addition, the wheelchair 1 comprises a second linear motor 8 for adjusting the support wheels 10, 11, which are attached to the same axle. In the side view of Fig. 2 The second linear motor 8 and the left support wheel 10 are visible. The second linear motor 8 is attached at one end to the base body 2 and at its other end to a strut 12 on which the left support wheel 10 is located.

[0021] A compressive force acts on the first linear motor 7 for adjusting the crawler track, and a tensile force acts on the second linear motor 8 for adjusting the support wheel 10. A compression spring 13, which is attached to the base body 2 on one side and to the strut 12 on the other, serves to relieve the load on the linear motors 7, 8. The compression spring 13 generates a compressive force that counteracts the force generated by the weight of the wheelchair 1, which would otherwise have to be absorbed by the linear motors 7, 8, thus relieving them. In this way, the working range of the linear motors 7, 8 can be better utilized.

[0022] Fig. 3 shows wheelchair 1 traveling up a staircase 14. Wheels 3, 4 are in a raised position relative to the crawler track 5, and support wheels 10, 11 are aligned approximately longitudinally with the crawler track 5. Accordingly, only the crawler track 5 touches the steps of the staircase 14.

[0023] Fig. 4 shows wheelchair 1 in the third operating mode, height adjustment mode, in the upper position. Wheelchair 1 is positioned on a surface with the two support wheels 10, 11 and the front end of the crawler track 5. Wheels 3, 4 are in an elevated position and spaced from the ground. The forces acting on the linear motors 7, 8 are reduced and at least partially compensated by compression spring 13.

[0024] Fig. 5 is a similar representation as Fig. 4 and shows the wheelchair 1 in the third operating mode, in height adjustment mode, in the lower position. The center of gravity of the wheelchair 1 is shifted forward, so that a maximum force acts on the first linear motor 7 of the crawler track 5. However, the first linear motor 7 is considerably relieved by the gas pressure spring 13. It can be seen that, starting from the Fig. 4 In the state shown, the wheels 3, 4 have been moved downwards so far that they, like the support wheels 10, 11 and the front end of the crawler track 5, are on the ground. At the same time, the seat 6 has been moved forward longitudinally. This position is preferably chosen when the user of the wheelchair 1 is sitting at a table.

[0025] Fig. 6 shows wheelchair 1 in parking mode, i.e., in the non-driven state. In accordance with the lower position of the height adjustment mode, wheelchair 1 rests on support wheels 10, 11 and the front end of the crawler track 1. However, wheels 3, 4 are in a higher position.

[0026] Fig. 7 finally shows the connection of the first linear motor 7 to the base body 2. In Fig. 7 Some components have been omitted for clarity. It can be seen that there are two parallel compression springs 13, which are attached at one end to the base body 2 and at the other end to the strut 12 of the support wheels 10, 11. The linear motor 9, which is also attached at its other end to the base body 2 of the wheelchair 1, is also attached to this strut. The first linear motor 7 is connected with its outer end, Fig. 7 lower end to the crawler track (not shown). The opposite end, Fig. 7 upper end is attached to the base body 2.

[0027] In all described positions, the compression spring 13 serves to generate a compressive force that counteracts the forces acting on the linear motors 7, 8 and thereby reduces and at least partially compensates them, so that the linear motors 7, 8 can be operated in an optimal operating range. List of reference symbols

[0028] 1Wheelchair 2Basic body 3Wheel 4Wheel 5Tracked chassis 6Seat 7First linear motor 8Second linear motor 10Jockey wheel 11Jockey wheel 12Strut 13Compression spring 14Stairs

Claims

1. Vehicle (1) for driving on a staircase (14) or a ramp, the vehicle comprising wheels (3, 4), a crawler track (5), a support (6) for carrying and transporting a load and a support wheel (10, 11) and being selectively operable in one of the following modes of operation: - a first operating mode, which is provided for a substantially level surface, in which the one or more wheels (3, 4) are driven, - a second operating mode, which is intended for driving on a staircase (14) or a ramp, in which the crawler track (5) is driven, - a third operating mode in which the height of the support (6) for carrying and transporting a load is adjustable and the vehicle (1) is supported on the crawler track (5) and the support wheel (10, 11), wherein the vehicle (1) comprises - at least one first linear motor (7) for adjusting the crawler track (5), - a second linear motor (8) for adjusting the support wheel (10, 11), - a lifting mechanism with a base body (2) on which the first linear motor (7) and the second linear motor (8) are arranged, characterized in that a spring (13) for relieving the first linear motor (7) and / or the second linear motor (8) is arranged on the lifting mechanism.

2. Vehicle according to claim 1, wherein the spring is arranged such that the first linear motor (7) for adjusting the crawler track (5) is relieved by a tensile force generated by the spring, which counteracts a compressive force acting on the first linear motor (7).

3. Vehicle according to claim 1 or 2, wherein the spring is designed as a compression spring (13) and is arranged in such a way that the second linear motor (8) for adjusting the support wheel (10, 11) is relieved by a compressive force generated by the compression spring (13), which counteracts a tensile force acting on the second linear motor (8).

4. Vehicle according to any one of the preceding claims, wherein two springs or compression springs (13) arranged in parallel are present.

5. Vehicle according to any one of the preceding claims, wherein the spring is designed as a gas pressure spring.

6. Vehicle according to any one of the preceding claims, which is designed to be operated in a self-balancing manner in the first operating mode.

7. Vehicle according to any one of the preceding claims, which is configured as a wheelchair (1) with a support configured as a seat (6).