DRIVE AND STEERING UNIT FOR INSTALLATION CONVEYOR VEHICLES

Description

[0001] The invention relates to an arrangement of a drive and steering unit for vehicles, in particular industrial trucks, for attachment to a vehicle chassis, comprising at least one slewing ring bearing with at least one drive motor and at least one gear stage, wherein the slewing ring bearing is horizontally aligned with the vehicle chassis.

[0002] Drive and steering units of this type are primarily used in industrial trucks to transport goods and materials. Forklifts, for example, are well-known industrial trucks that use their forks to lift and transport pallets and, for this purpose, have a drive and steering unit at the rear of the vehicle. The drive is provided by a wheel, which is driven by an electric motor via a gearbox and connected to the vehicle chassis by a slewing ring bearing. A steering motor is also included, which controls the steering angle of the gearbox unit and wheel. The slewing ring bearing allows the wheel to rotate 360 ​​degrees, resulting in a very small turning radius. This turning radius is advantageous when, for example, a forklift needs to move back and forth between shelves to store goods or pick them up for further transport.

[0003] The known drive and steering units for industrial trucks are designed such that the slewing ring bearing is connected to the gearbox and wheel via the inner slewing ring, while the drive motor is mounted above the slewing ring bearing. To enable a connection between the drive motor and gearbox, the slewing ring bearing has a larger opening, allowing the drive motor to be connected, for example, to the inner ring of the slewing ring bearing and to rotate along with the wheel.

[0004] This design is perfectly suitable for the installation of forklifts because sufficient vertical installation space is available.

[0005] In many cases, forklifts are to be replaced by self-propelled industrial trucks, which are designed to be as low-profile as possible for transporting goods. It is known to connect the chassis of such a vehicle to a mounting plate on which both a drive motor with gearbox and a steering motor are mounted separately. For such drives, a slewing ring bearing is not used; instead, the steering motor determines the direction of travel for the wheel via a driven toothed ring. The individual components are connected separately to the mounting plate, and only the required torque of the steering motor and the drive motor is transmitted via suitable means. A disadvantage of this design is that the mounting plate with its components requires a relatively large amount of space, which could be used for other purposes, such as housing the battery.

[0006] From EP 1 946 952 A1, a drive unit is known which provides for an arrangement of the drive motor and the steering motor below the slewing ring bearing, with the drive motor being horizontally oriented. The transverse orientation of the drive motor necessitates increased installation space with a larger footprint, thus limiting the installation options.

[0007] From CN 108 216 422 A, a drive unit for industrial trucks is known, which has a driven wheel in a housing and a drive motor flanged below the housing for the steering movement. Such drives are intended for self-propelled industrial trucks, where, for example, four such drives are used.

[0008] The present invention is based on the objective of providing a novel drive and steering unit which has the lowest possible overall height and also requires little space below the transport surface of such a forklift truck.

[0009] According to the invention, to solve the problem, the drive motor with its axis of rotation and at least one gear stage is arranged below and perpendicular to the slewing ring bearing, and the motor shield of the drive motor, lying parallel to the slewing ring bearing, simultaneously forms the upper cover of the gearbox housing. Advantageous embodiments of the invention are disclosed in the dependent claims.

[0010] By mounting the slewing ring bearing to the vehicle chassis, preferably using the outer ring of the slewing ring bearing, and by arranging the drive motor with at least one gear stage vertically below the slewing ring bearing, the overall height of such a drive and steering unit can be significantly reduced. In the solution according to the invention, all the necessary components for the drive and steering unit can be arranged below the slewing ring bearing, so that the required support surface for the goods to be transported is available above the slewing ring bearing. Furthermore, the slewing ring bearing enables greater vehicle maneuverability, as it can easily move through narrow aisles or lanes and also has a small turning radius, because the drive motor with its wheel is steered directly in the desired direction via the slewing ring bearing.

[0011] The motor shield of the drive motor simultaneously forms the upper cover of the gearbox housing, thus reducing the size and also the number of individual components of a drive and steering unit.

[0012] To further reduce the size of the assembly, an embodiment of the invention provides that the drive and steering motors share a common motor shield, so that both motors are directly connected to each other, with the motor shield of the drive and steering motors simultaneously forming the upper end of the gearbox housing. In this way, a direct connection between the drive and steering motors and the gearbox housing is achieved, resulting in a compact assembly and significantly reducing assembly effort. However, it remains possible to replace either the drive or steering motor individually in the event of a repair.

[0013] In an embodiment of the invention, it is provided that the outer ring of the slewing ring bearing is connected to the vehicle chassis and the inner ring of the slewing ring bearing is connected to the engine shield, wherein in a preferred embodiment the inner ring of the slewing ring bearing can be designed as an engine shield.

[0014] In a further embodiment of the invention, the drive motor is flanged laterally next to the at least one gear stage to reduce the size of the assembly. A steering motor can also be arranged vertically next to the drive motor. By arranging the drive and steering motors directly next to the gear stage and thus opposite the wheel, an extremely compact assembly is created that can be mounted under the vehicle without requiring much space. The required steering movement is transmitted directly from the steering motor to the stationary outer ring of the slewing ring, resulting in direct and responsive steering.

[0015] In a further embodiment of the invention, the drive and steering motor is arranged on one side of the at least one gear stage, and the wheel is positioned diametrically opposite it. The gear stage is thus located between the wheel and the drive and steering motor, allowing the wheel to be directly connected to the gear stage on one side, while the drive and steering motor is located on the other side of the gear stage. This measure significantly simplifies the replacement of the wheel, as neither the drive motor nor the steering motor needs to be removed beforehand.

[0016] In an alternative embodiment, a mounting plate is arranged between the motor shield and the inner ring of the slewing ring bearing. This mounting plate serves to attach any further components that may be required, and is specifically designed to accommodate at least one sensor for detecting the steering angle. Since this is a self-driving vehicle without a driver, a monitoring function is necessary to detect the steering angle, for example, so that corrective action can be taken via a corresponding control system.The self-driving vehicles are controlled, for example, via inductive contact surfaces. An inductive sensor detects the required direction of travel, and a steering sensor measures the steering angle to ensure that the wheel and its steering angle correspond to the required direction. In this way, each individual vehicle can be kept on its intended route with high accuracy. Meanwhile, a computer system and radio link allow for the monitoring, control, and management of each individual vehicle in the background.

[0017] In this embodiment of the invention, the drive motor drives a spur gear as the first gear stage via a drive pinion. The spur gear is connected to a drive shaft which has helical teeth at its other end. These helical teeth mesh with a hollow shaft as the second drive stage, and the second drive stage is directly coupled to the impeller. Thus, there is only a single vertically extending drive shaft, which is driven at one end by the drive pinion and the spur gear, and at the other end, via the helical teeth, enables the drive of the impeller.

[0018] In a further embodiment of the invention, the steering motor meshes with a pinion on the outer ring of the slewing ring bearing, which is connected to the vehicle chassis. In this case, the spur gear and the inner ring of the slewing ring bearing can form a single unit that is rigidly connected to the vehicle chassis, so that the inner ring of the slewing ring bearing, including the gearbox, drive motor, and wheel, can be steered in any desired direction by means of the drive pinion and the steering motor.

[0019] In a further embodiment, it is provided that the electrical connection cables of the drive and steering motor are routed through the slewing ring bearing into the vehicle chassis and connected to the required control units and, in particular, a power supply source.

[0020] The special feature of the present invention is that it creates a compact unit for a drive and steering system, intended for powering self-propelled vehicles, particularly industrial trucks. The compact design, with the drive motor, steering motor, gearbox, and wheel arranged below a slewing ring bearing, ensures that the vehicle's transport area can be fully utilized across its entire length and width without any obstruction during the transport of goods. A particular advantage is that the drive motor for the wheel and the steering motor are flange-mounted to the gearbox on the side, but are removable, opposite the wheel. This allows for the removal of individual components, including the wheel, at any time. In particular, the wheel or wheel tires can be replaced at any time without requiring extensive disassembly.

[0021] The invention will be explained in more detail below using the figures.

[0022] It shows Fig. 1 shows a perspective view of a drive and steering unit for a forklift truck, Fig. 2 shows a top view of the drive and steering unit with indication of the sections, Fig. 3 shows a section through the drive and steering unit according to Figure 2 along the section line AA, Fig. 4, a section through the drive and steering unit according to Figure 2 along the section line BB and Fig. 5 a section through the drive and steering unit according to Figure 2 along the CC intersection line.

[0023] Figure 1 Figure 1 shows a perspective view of the drive and steering unit 1, consisting of a slewing ring bearing 2, a drive motor 3 and a steering motor 4. A wheel 6 is driven via the drive motor 3 and a gearbox.

[0024] The slewing ring bearing 2 consists of an outer slewing ring bearing 7 and an inner slewing ring bearing 8. The outer slewing ring bearing is connected to a chassis of the industrial truck (not shown) and has a toothed ring 9 on its outer circumference, which meshes with a pinion 5 mounted on the shaft 11 of the steering motor 4. Thus, the steering motor 4 and the pinion 5 allow the entire drive assembly to be moved 360 degrees. The inner slewing ring bearing 8, on the other hand, serves to mount the drive motor 3, steering motor 4, and gearbox to which the wheel 10 is attached. In the illustrated embodiment, the connection between the inner slewing ring bearing and a motor shield 12 is made by means of a screw connection 13, with the drive motor 3 being connected to the motor shield 12 via a screw connection 14 and the steering motor 4 via a screw connection 15.Furthermore, the gearbox, as can be seen more clearly in later views, is also connected to the motor shield 12. As a result, a compact unit is formed which, due to the geometry and arrangement of the drive motor 3 and steering motor 4, can be mounted beneath a forklift truck. From this view, the connection terminals 16 of the drive motor 3 and the connection terminals 17 of the steering motor 4 are also visible. The power supply to the drive motor 3 and steering motor 4 is provided via a cable connection through the slewing ring bearing 2 to the chassis of the forklift truck.

[0025] Figure 2 Figure 1 shows a top view of the drive and steering unit 1 with a view of the slewing ring bearing 2, consisting of the outer slewing ring bearing 7 and the inner slewing ring bearing 8. The drive motor 3 and the steering motor 4 are flanged to the side via the motor shield 12. Furthermore, the section lines according to the diagram are shown in this illustration. Figures 3 to 5visible.

[0026] Figure 3Figure 1 shows a section through the drive and steering unit 1 along line AA. In the upper area is the slewing ring bearing 2 with its outer ring 7 and inner ring 8, which are mutually supported by a bearing element 20. The bearing elements 20 are additionally sealed by sealing elements 21. In this case, the section passes through the center point of the slewing ring bearing 2, so that the outer contour of the drive motor 3 is visible. The drive motor 3 is flanged to the motor end shield 12, which is also used to mount the gearbox housing. The gearbox consists of a spur gear 23 in a first drive stage, which is driven by a spur gear pinion of the drive motor 3. The spur gear pinion is not visible in this sectional view.The spur gear 23 is fixedly mounted on a drive shaft 24, which is supported by bearing elements 25 in the upper region and bearing elements 26 in the lower region. Diametrically opposite the spur gear 23, the drive shaft 24 is equipped with helical teeth 27, which mesh directly with another helical toothing 28. The helical toothing 28 is part of a hollow shaft 29, which serves to receive the wheel 10. In this case, the ring gear 29 is supported by bearing elements 32, 33 against a gearbox housing 34, which is integrally connected to, or rather, part of the gearbox housing. The wheel 10 consists of a rim 30 and a tire 31.Both the drive motor 3 and the steering motor 4 (not visible in this view), as well as the gearbox, are rigidly connected to the inner ring of the slewing ring bearing 8 via the motor shield 12. Therefore, a steering movement of the steering motor 4 via the outer toothed ring 9 of the outer ring of the slewing ring bearing 7 immediately results in a rotational movement of the entire drive and steering unit 1 relative to the vehicle chassis. The advantage of this arrangement is that the wheel 10 can be changed without disassembling the drive motor 3 or the steering motor 4, because the wheel 10 is located on one side of the gearbox stage and the drive motor 3 and the steering motor 4 are on the opposite side. Furthermore, the use of a common motor shield, which also houses the gearbox, results in an extremely compact unit requiring minimal space.

[0027] Figure 4Figure 1 shows a section through the drive and steering unit 1 along section line BB. The section runs according to... Figure 2 In this case, the drive motor 3 displaces the center point of the slewing ring bearing 2. For this reason, the drive motor 3 is shown in its entirety, and a pinion 35 of the drive motor 3 is visible, which meshes with the spur gear 23 of the gear stage. The gear stage with spur gear 23, drive shaft 24, and helical gear 27, which meshes with a ring gear 29, corresponds to the description according to [reference to relevant section]. Figure 3 The sectioning technique results in the representation being angled relative to the axis of rotation of the ring gear. The drive motor 3 consists of a standard electric motor.

[0028] Figure 5 Figure 1 shows a section through the drive and steering unit 1 along the connecting line CC through the center point of the slewing ring bearing 2 and the steering motor 4. The construction of the gear stage corresponds to the previous representation according to the figures. Figures 3and 4 The sectioning technique shows the gear stages and the wheel cut at an angle, while the steering motor 4 with drive shaft 11 and a pinion 5 are visible. The pinion 5 meshes with the toothed ring 9 of the slewing ring bearing outer ring 7 to execute the steering movement. The steering motor 4 itself consists of a standard electric motor, which in this case is equipped with a planetary gear 36. Reference symbol list

[0029] 1 Drive and steering unit 2 Slewing ring bearing 3 Drive motor 4 Steering motor 5 Pinion 6 Wheel 7 Slewing ring bearing outer ring 8 Slewing ring bearing inner ring 9 Ring gear 10 Wheel 11 Shaft 12 Motor shield 13 Screw connection 14 Screw connection 15 Screw connection 16 Terminal blocks 17 Terminal blocks 20 Bearing element 21 Sealing element 23 Spur gear 24 Drive shaft 25 Bearing element 26 Bearing element 27 Helical gear 28 Helical gear 29 Hollow shaft 30 Rim 31 Tire 32 Bearing element 33 Bearing element 34 Gearbox stub 35 Pinion 36 Planetary gear

Claims

1. Arrangement of a drive and steering unit (1) for vehicles, in particular industrial trucks, for attachment to a vehicle chassis, comprising at least one slewing ring bearing (2) with at least one drive motor (3) and at least one gear stage, wherein the slewing ring bearing (2) is connected to the vehicle chassis in a horizontally aligned manner, characterized in that the drive motor (3) is arranged with its axis of rotation and at least one gear stage below and at right angles to the slewing ring bearing (2), and the motor shield (12) of the drive motor, lying parallel to the slewing ring bearing (2), simultaneously forms the upper cover of the gearbox housing.

2. Drive and steering unit (1) according to claim 1, characterized in that the drive motor (3) and steering motor (4) have a common motor shield (12) and the motor shield (12) simultaneously forms the upper cover of the gearbox housing.

3. Drive and steering unit (1) according to any one of claims 1 or 2, characterized in that a slewing ring outer ring (7) is connected to the vehicle chassis and a slewing ring inner ring (8) is connected to the motor shield (12), or that a slewing ring inner ring (8) is provided as the motor shield (12).

4. Drive and steering unit (1) according to any one of claims 1 to 3, characterized in that the drive motor (3) is flanged laterally adjacent to the at least one transmission stage, and / or that a steering motor (4) is arranged in vertical alignment adjacent to the drive motor (3).

5. Drive and steering unit (1) according to any one of claims 1 to 4, characterized in that the drive motor (3) and steering motor (4) are arranged on one side of the at least one transmission stage and the impeller (10) is arranged diametrically opposite them.

6. Drive and steering unit (1) according to any one of claims 1 to 5, characterized in that a mounting plate is arranged between the motor shield (12) and the inner ring (8) of the slewing ring bearing.

7. Drive and steering unit (1) according to claim 6, characterized in that the mounting plate is provided for accommodating at least one sensor for detecting a steering angle.

8. Drive and steering unit (1) according to any one of claims 1 to 7, characterized in that the drive motor (3) drives a spur gear (23) as a first gear stage via a drive pinion (35), wherein the spur gear (23) is connected in a rotationally fixed manner to a drive shaft (24) at one end, which has helical teeth (27) at the other end, which mesh with further helical teeth (28) of a hollow shaft (29) as a second drive stage.

9. Drive and steering unit (1) according to one or more of claims 1 to 8, characterized in that the second drive stage is coupled directly to the impeller (10) via the hollow shaft (29).

10. Drive and steering unit (1) according to one or more of claims 1 to 9, characterized in that the steering motor (4) meshes via a pinion (5) with the outer ring (7) of the slewing ring bearing, which is connected to the vehicle chassis.

11. Drive and steering unit (1) according to one or more of claims 1 to 10, characterized in that the electrical connection cables of the drive motor (3) and steering motor (4) are routed through the slewing ring bearing (2) into the vehicle chassis.

12. Use of a drive and steering unit (1) according to one of claims 1 to 11 for an industrial truck.