Wheel-side driving system for aerial work platform

Abstract

The invention discloses a wheel edge driving system for an aerial work platform, which comprises a motor and a speed reducing mechanism, the speed reducing mechanism comprises a first planetary gear mechanism and a second planetary gear mechanism, the first planetary gear mechanism and the second planetary gear mechanism are both composed of a sun gear, a planetary gear and a gear ring, and the planetary gear is shared by the first planetary gear mechanism and the second planetary gear mechanism; a sun gear of the first planetary gear mechanism is driven by a motor, the sun gear drives a planetary gear to drive a sun gear and a gear ring of the second planetary gear mechanism to rotate, and the gear ring of the second planetary gear mechanism is used for driving a tire to rotate; the number of teeth corresponding to the gear rings and the planet gears of the two planet gear mechanisms meets the set requirement. The device can realize high reduction ratio, and is simple in structure and small in size.

Description

Technical Field

[0001] The invention relates to a wheel side drive system, in particular to a wheel side drive system for an aerial work platform. Background Art

[0002] When the aerial work platform moves to the working position, a wheel-side drive system is needed to drive the tires to operate. Existing wheel-side drive systems basically use a combination of asynchronous motors, traditional planetary reducers, brakes and encoders. Traditional planetary reducers must set up multiple planetary gear mechanisms to achieve a high reduction ratio. Each planetary gear mechanism includes a sun gear, planetary gears, planetary carriers and ring gears. When multiple planetary gear mechanisms are stacked, the overall structure is complex, which will make the overall volume larger. In addition, the presence of multiple planetary carriers and bearings in multiple planetary gear mechanisms will also increase the number of failure points. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a wheel-side drive system for an aerial work platform which can achieve a high reduction ratio and has a simple structure and a small size.

[0004] Technical solution: The wheel-side drive system for an aerial work platform described in the present invention comprises a motor and a reduction mechanism, wherein the reduction mechanism comprises a first planetary gear mechanism and a second planetary gear mechanism, both of which are composed of a sun gear, a planetary gear and a ring gear, and both share a planetary gear; the sun gear of the first planetary gear mechanism is driven by the motor, and the sun gear drives the planetary gear to drive the sun gear and the ring gear of the second planetary gear mechanism to rotate, and the ring gear of the second planetary gear mechanism is used to drive the tire to rotate; the structures of the two planetary gear mechanisms meet the following requirements:

[0005] p1×r2-p2×r1=NP

[0006] Among them, p1 is the number of teeth of the planetary gear matching the first planetary gear mechanism, p2 is the number of teeth of the planetary gear matching the second planetary gear mechanism, r1 is the number of teeth of the ring gear of the first planetary gear mechanism, r2 is the number of teeth of the ring gear of the second planetary gear mechanism, N is an arbitrary positive integer, and P is the total number of planetary gears.

[0007] Based on the above technical solution, the reduction mechanism adopts two planetary gear mechanisms, and the two planetary gear mechanisms share a planetary wheel. The planetary wheels are respectively provided with a number of teeth matching the two planetary gear mechanisms, and the two numbers of teeth of the planetary wheels and the number of teeth of the ring gears of the two planetary gear mechanisms are set to satisfy the above-mentioned specific relationship. The planetary wheels can be operated simultaneously in the two planetary gear mechanisms without getting stuck. Such a setting not only saves two planetary carriers, simplifies the overall structure of the device, reduces the size of the device and the failure points, but also, compared with a single planetary gear mechanism, the two planetary gear mechanisms cooperate with each other to increase the reduction ratio and provide a larger output torque.

[0008] Preferably, the motor is a frameless torque motor.

[0009] The frameless torque motor has higher control accuracy than the asynchronous motor.

[0010] Preferably, the ring gear of the first planetary gear mechanism is fixed.

[0011] The ring gear of the first planetary gear mechanism is fixed, so that the planetary gear can serve as the only power output of the first planetary gear mechanism to effectively drive the sun gear and the ring gear of the second planetary gear to rotate.

[0012] Preferably, the motor and the reduction mechanism are respectively arranged in the first shell and the second shell, and the second shell is rotatably connected to the first shell.

[0013] The motor and the reduction mechanism are arranged in two separate housings, so that the two can be separated during subsequent disassembly and maintenance.

[0014] Preferably, the first housing is provided with a raised ring, the inner wall of which is provided with a gear ring of a first planetary gear mechanism; the inner wall of the second housing is provided with a gear ring of a second planetary gear mechanism, and the second housing is connected to the wheel rim.

[0015] Preferably, the second housing comprises a detachably connected end cover and a bearing seat, the bearing seat is rotatably connected to the outside of the first housing, and the ring gear of the second planetary gear mechanism is arranged on the inner wall of the bearing seat.

[0016] The second housing adopts a detachably connected end cover and bearing seat, so that when the planetary gear mechanism needs to be repaired later, the end cover can be directly removed to expose the internal planetary gear mechanism for repair.

[0017] Preferably, two end faces of the sun gear of the second planetary gear mechanism are in contact with the end face and end cover of the sun gear of the first planetary gear mechanism respectively.

[0018] The sun gear of the second planetary gear mechanism is equivalent to being clamped between the end cover and the sun gear of the first planetary gear mechanism to achieve positioning, so there is no need to set up an additional connecting mechanism to achieve the positioning of the sun gear, which simplifies the structure.

[0019] Preferably, both end faces of the sun gear of the second planetary gear mechanism are provided with lubricating oil channels.

[0020] Both end faces of the sun gear of the second planetary gear mechanism are provided with lubricating oil passages to fill lubricating oil into the contact end faces, thereby reducing wear.

[0021] Preferably, one end of the first shell away from the second shell is connected to a third shell, and the encoder and the brake are arranged in the third shell.

[0022] The encoder and the brake are arranged in the third housing to prevent them from being exposed to the outside and causing damage. At the same time, all components are integrated into a whole through the three housings, which also improves the integration and facilitates subsequent installation and use.

[0023] Beneficial effects: Compared with the prior art, the present invention has the following significant effects: by using two planetary gear mechanisms to share a planetary wheel of a specific structure, there is no need to set up a planetary carrier, which simplifies the structure, reduces the size of the device and the number of failure points, and at the same time, compared with a single planetary gear mechanism, it can improve the reduction ratio and provide a larger output torque. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is an axial cross-sectional view of the device. DETAILED DESCRIPTION

[0025] As shown in the figure, a wheel-side drive system for an aerial work platform described in the present invention includes a motor 1, a reduction mechanism 2, an encoder 4 and a brake 5, the reduction mechanism 2 includes a first planetary gear mechanism and a second planetary gear mechanism, both of which are composed of a sun gear, a planetary gear 3 and a ring gear, and both share the planetary gear 3; the sun gear of the first planetary gear mechanism is driven by the motor 1, and the sun gear drives the planetary gear 3 to drive the sun gear and the ring gear of the second planetary gear mechanism to rotate, and the ring gear of the second planetary gear mechanism is used to drive the tire to rotate.

[0026] The motor 1 adopts a frameless torque motor, and of course an asynchronous motor or other types of motors can also be adopted; the motor 1 is arranged in the first housing 6, and the rotor of the motor 1 is connected to the rotating shaft 9, and the rotating shaft 9 is rotatably connected in the first housing 6; the rotating shaft 9 is equivalent to the output shaft of the motor 1, and both ends of the rotating shaft 9 pass through the first housing 6, one end is connected to the reduction mechanism 2, and the other end is connected to the encoder 4 and the brake 5.

[0027] The reduction mechanism 2 is arranged in the second housing 7, and the second housing 7 is rotatably connected to the first housing 6; the reduction mechanism 2 includes two axially stacked planetary gear mechanisms, the first planetary gear mechanism is close to the first housing 6, and the other is the second planetary gear mechanism, and the two planetary gear mechanisms are composed of a sun gear, a planetary gear 3 and a ring gear, and both share the planetary gear 3.

[0028] For the sake of convenience, the sun gear and the ring gear of the first planetary mechanism are referred to as the first sun gear 10-1 and the first ring gear 10-2, respectively, and the sun gear and the ring gear of the second planetary gear mechanism are referred to as the second sun gear 11-1 and the second ring gear 11-2, respectively; the two ends of the planetary gear 3 are respectively provided with the number of teeth matching the first planetary gear mechanism and the second planetary gear mechanism, and the number of teeth at its two ends is actually the two planetary gear mechanisms that need to satisfy the following formula

[0029] p1×r2-p2×r1=NP

[0030] Among them, p1 is the number of teeth of the planetary gear 3 matching the first planetary gear mechanism, p2 is the number of teeth of the planetary gear 3 matching the second planetary gear mechanism, r1 is the number of teeth of the first ring gear 10-2, r2 is the number of teeth of the second ring gear 11-2, N is any positive integer, and P is the total number of planetary gears 3; if the above formula is satisfied, the planetary gear 3 can operate in two planetary gear mechanisms at the same time.

[0031] The first sun gear 10-1 is connected to the rotating shaft 9, and a protruding ring is provided at one end where the first shell 6 and the second shell 7 are connected. The first ring gear 10-2 is arranged in the protruding ring. The two can be formed as one piece, or the first ring gear 10-2 can be arranged separately and then fixed to the inner side of the protruding ring. No matter how it is arranged, the first shell 6 is fixed, so the first ring gear 10-2 is also fixed and cannot rotate; the two end faces of the second sun gear 11-1 respectively abut against one end face of the first sun gear 10-1 and the end face of the second shell 7. The second sun gear 11-1 can rotate circumferentially, but cannot move axially. Because the planetary gear 3 is arranged on the outside of the second sun gear 11-1, it cannot move radially either. Lubricating oil channels for lubricating oil are provided on the two end faces of the second sun gear 11-1.

[0032] The second housing 7 includes an end cover 7-1 and a bearing seat 7-2, which are bolted together; the bearing seat 7-2 is mounted on the outside of the first housing 6, and the bearing seat 7-2 and the first housing 6 are rotatably connected through a plurality of bearings; a second gear ring 11-2 is provided on the inner wall of the bearing seat 7-2, and similarly, the second gear ring 11-2 and the bearing seat 7-2 can be integrally formed or the second gear ring 11-2 can be fixedly connected to the bearing seat 7-2, and the bearing seat 7-2 is bolted to the wheel edge, and the rotation of the second gear ring 11-2 drives the bearing seat 7-2 to rotate, thereby driving the tire to rotate; The inner end face of the end cover 7-1 is in contact with the outer end face of the second sun gear 11-1; the bearing seat 7-2 can also be arranged into an outer ring and an inner ring, the outer ring is mounted on the outside of the first shell 6, the inner ring is connected between the end cover 7-1 and the outer ring, the inner diameter of the inner ring is smaller than the inner diameter of the outer ring, and the second ring gear 11-2 is arranged on the inner side wall of the inner ring; the two ends of the planetary gear 3 are respectively in contact with the end cover 7-1 and the first shell 6, and the teeth of the planetary gear 3 are respectively engaged with the two sun gears and the ring gear, so that it can only rotate on its own and around the sun gear without axial and radial movement.

[0033] The end of the first shell 6 away from the second shell 7 is connected to the third shell 8, and the encoder 4 and the brake 5 are arranged in the third shell 8; the encoder is divided into a stator and a rotor part, the rotor part is installed on the rotating shaft 9 and rotates at the same speed as the rotating shaft 9, and the stator part is installed on the third shell 8 by bolts. When the rotating shaft 9 rotates, the slots on the encoder stator and the stator form a pulse model through electromagnetic action, which can be converted into the measured speed of the rotating shaft 9; the brake 5 is divided into a stator and a rotor part, the rotor part is installed on the rotating shaft 9 and rotates at the same speed as the rotating shaft 9, and the stator part is installed on the third shell 8 by bolts. When the brake is not energized, the stator clamps the rotor through the spring, and the brake is locked, thereby forming a parking state. When the brake is energized, the internal solenoid valve acts on the spring, so that the brake rotor, that is, the rotating shaft 9, becomes a free state and can rotate and work under the drive of the motor 1.

Claims

1. A wheel drive system for an aerial work platform, comprising a motor (1) and a speed reduction mechanism (2), characterized in that: The speed reduction mechanism (2) comprises a first planetary gear mechanism and a second planetary gear mechanism, both of which are composed of a sun gear, a planetary gear (3) and a ring gear, and both share the planetary gear (3); the sun gear of the first planetary gear mechanism is driven by a motor (1), and the sun gear drives the planetary gear (3) to drive the sun gear and the ring gear of the second planetary gear mechanism to rotate, and the ring gear of the second planetary gear mechanism is used to drive the tire to rotate; the structures of the two planetary gear mechanisms meet the following requirements: p1×r2-p2×r1=NP Wherein, p1 is the number of teeth of the planetary gear (3) matching the first planetary gear mechanism, p2 is the number of teeth of the planetary gear (3) matching the second planetary gear mechanism, r1 is the number of teeth of the ring gear of the first planetary gear mechanism, r2 is the number of teeth of the ring gear of the second planetary gear mechanism, N is an arbitrary positive integer, and P is the total number of planetary gears (3).

2. A wheel drive system for an aerial work platform according to claim 1, characterized in that: The motor (1) is a frameless torque motor.

3. A wheel drive system for an aerial work platform according to claim 1, characterized in that: The ring gear of the first planetary gear mechanism is fixed.

4. A wheel drive system for an aerial work platform according to claim 3, characterized in that: The motor (1) and the speed reduction mechanism (2) are respectively arranged in a first housing (6) and a second housing (7), and the second housing (7) is rotatably connected to the first housing (6).

5. A wheel drive system for an aerial work platform according to claim 4, characterized in that: The first housing (6) is provided with a raised ring, the inner wall of which is provided with a gear ring of a first planetary gear mechanism; the inner wall of the second housing (7) is provided with a gear ring of a second planetary gear mechanism, and the second housing (7) is connected to the wheel rim.

6. A wheel drive system for an aerial work platform according to claim 5, characterized in that: The second housing (7) comprises a detachably connected end cover (7-1) and a bearing seat (7-2); the bearing seat (7-2) is rotatably connected to the outside of the first housing (6); and the ring gear of the second planetary gear mechanism is arranged on the inner wall of the bearing seat (7-2).

7. A wheel drive system for an aerial work platform according to claim 6, characterized in that: The two end faces of the sun gear of the second planetary gear mechanism are in contact with the end face of the sun gear of the first planetary gear mechanism and the end cover (7-1) respectively.

8. A wheel drive system for an aerial work platform according to claim 7, characterized in that: Both end surfaces of the sun gear of the second planetary gear mechanism are provided with lubricating oil channels.

9. The wheel drive system for an aerial work platform according to claim 1, characterized in that: One end of the output shaft of the motor (1) is connected to the sun gear of the first planetary gear mechanism, and the other end is connected to an encoder (4) and a brake (5).

10. A wheel drive system for an aerial work platform according to claim 9, characterized in that: One end of the first housing (6) away from the second housing (7) is connected to a third housing (8), and the encoder (4) and the brake (5) are arranged in the third housing (8).

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