Electric capstan capable of improving release speed of traction element

Abstract

The invention provides an electric capstan for improving the release speed of a traction element. The electric capstan comprises an actuator (5); the transmission and braking device (4) is in transmission connection with the actuator (5); one end of the transmission shaft (3) is connected with the transmission and braking device (4); the speed change assembly (1) comprises a power input element and a power output element, and the other end of the transmission shaft (3) interacts with the power input element; the drum (2) is connected with the power output element of the speed change assembly (1), the traction element is wound on the drum (2), and the electric capstan is configured in the mode that the other end of the transmission shaft (3) is combined with the power input element when the traction element is tightened, and the other end of the transmission shaft (3) is separated from the power input element when the traction element is released in an idle load mode. According to the electric capstan, different working conditions of no-load rope releasing and load working can be automatically switched, manual intervention is not needed, and the working intensity is effectively reduced.

Description

Technical Field

[0001] The present invention relates to the field of transmission or traction devices, and particularly to an electric winch for improving the release speed of a pulling element. Background Art

[0002] An electric winch is a tool that drives a drum by a motor and winds a flexible member (steel wire rope, chain, etc.) to complete a traction operation. Here, the flexible member serves as a pulling element to achieve the traction operation. Electric winches are commonly used in fields such as handling work, ship docks, vehicle towing, and fire rescue.

[0003] In order to achieve the best cost performance, existing electric winches usually have a large transmission ratio in the reduction mechanism. When using the winch, the rope needs to be released from the drum first, that is, pay out the rope. At this time, the motor rotates, drives the drum to rotate through the reduction mechanism. However, due to the large transmission ratio of the reduction mechanism, the drum rotates at a low speed, and the release speed of the rope is much lower than the walking speed of the user. Therefore, in order to improve the use efficiency and the response speed in some working conditions, when paying out the rope, the drum is separated from the motor, and the user pulls the rope to achieve the pay-out operation. At this time, the walking speed of the user determines the pay-out speed. When winding the rope and working under load, the drum and the motor are reliably engaged, and the motor drives the drum to rotate to complete the winch work safely and reliably. In existing electric winches, the gear ring is released manually or automatically to make the reduction mechanism idle and achieve the separation of the motor and the drum for fast rope pay-out. When it is necessary to wind the rope or the electric winch works under load, it is necessary to manually or remotely lock the gear ring again to make the reduction mechanism work normally, and the motor can drive the drum to rotate.

[0004] It can be seen that in order to achieve fast rope pay-out in existing electric winches, manual intervention is required to separate the drum from the motor. Then, when the electric winch needs to work normally, it is also necessary to operate to make them combine. Therefore, the operation is relatively cumbersome, which affects the work efficiency and has a large labor intensity. Summary of the Invention

[0005] The purpose of the present invention is to at least partially overcome the defects of the prior art and provide an electric winch for improving the release speed of a pulling element.

[0006] The purpose of the present invention is also to provide an electric winch for improving the release speed of a pulling element, which can automatically increase the pay-out speed when paying out the rope without manual intervention.

[0007] The purpose of the present invention is also to provide an electric winch for improving the release speed of a pulling element, which improves the work efficiency and reduces the labor intensity.

[0008] To achieve the above purpose or one of the purposes, the technical solution of the present invention is as follows:

[0009] An electric winch for improving the release speed of a pulling element, the electric winch comprising:

[0010] An actuator;

[0011] A transmission and braking device, drivingly connected to the actuator, for transmitting the driving force of the actuator and capable of achieving braking under predetermined conditions;

[0012] A transmission shaft, one end of the transmission shaft being connected to the transmission and braking device;

[0013] A speed change assembly, including a power input element and a power output element, the other end of the transmission shaft interacting with the power input element; and

[0014] A drum, the drum being connected to the power output element of the speed change assembly, the pulling element being wound around the drum,

[0015] wherein the electric winch is configured such that the other end of the transmission shaft engages with the power input element when the pulling element is being wound up, and disengages from the power input element when the pulling element is being released under no-load conditions.

[0016] According to a preferred embodiment of the present invention, the electric winch further comprises:

[0017] A transmission disk, fixedly provided on the other end of the transmission shaft; and

[0018] A plurality of locking blocks, hinged on the transmission disk and configured to be able to extend or retract relative to the center of the transmission disk,

[0019] wherein a plurality of grooves are provided on the power input element, and the power input element is configured such that the locking blocks can extend into the grooves in a state of extending relative to the center of the transmission disk so that the transmission disk and the power input element rotate simultaneously, and do not extend into the grooves in a state of retracting relative to the center of the transmission disk so that the transmission disk and the power input element rotate out of sync.

[0020] According to a preferred embodiment of the present invention, the power input element comprises:

[0021] A central hole, provided in the center of the power input element for the transmission shaft to pass through; and

[0022] A concave portion, the concave portion being a groove in a substantially disk shape, located in the end face of the power input element facing the transmission disk, the transmission disk being at least partially received in the concave portion,

[0023] wherein a plurality of bosses are formed on the outer peripheral surface of the disk-shaped groove of the concave portion, and the grooves are formed between adjacent bosses to form a structure in which the bosses and the grooves are staggered.

[0024] According to a preferred embodiment of the present invention, a plurality of locking blocks are strip-shaped, one ends of the plurality of locking blocks are respectively hinged at positions on the side surface of the transmission disk near the outer periphery, and the other ends of the plurality of locking blocks are free ends and can extend or retract relative to the center of the transmission disk.

[0025] According to a preferred embodiment of the present invention, the plurality of locking blocks are circumferentially symmetrically distributed relative to the center of the transmission disk.

[0026] According to a preferred embodiment of the present invention, the number of the locking blocks is three.

[0027] According to a preferred embodiment of the present invention, a plurality of concave spaces are provided in the side surface of the transmission disk, and the locking blocks are arranged in the concave spaces.

[0028] According to a preferred embodiment of the present invention, the electric winch further includes a housing, and the housing surrounds the outside of the speed change assembly and supports the speed change assembly.

[0029] According to a preferred embodiment of the present invention, the electric winch further includes a restraint element, and the restraint element is arranged on the inner end surface of the housing. The restraint element includes:

[0030] a base portion, which contacts the inner end surface of the housing and can rotate relative to the inner end surface; and

[0031] a periphery extending from the outer periphery of the base portion towards the power input element, forming an accommodation space. A plurality of teeth and a plurality of tooth grooves are provided on the periphery.

[0032] wherein, at least a part of the transmission disk is located in the accommodation space, and the other end of the locking block is always located in the tooth groove;

[0033] The shape of the locking block is adapted to be able to extend or retract relative to the center of the transmission disk under the action of the restraint element.

[0034] According to a preferred embodiment of the present invention, the restraint element extends into the inner concave portion, and the outer diameter of the periphery of the restraint element is smaller than the inner diameter of the boss of the inner concave portion.

[0035] According to a preferred embodiment of the present invention, the housing is composed of an end cover and a housing body.

[0036] According to a preferred embodiment of the present invention, the speed change assembly includes a first-stage planetary gear set, a second-stage planetary gear set and a third-stage planetary gear set;

[0037] The first-stage planetary gear set includes a first-stage sun gear, a first-stage ring gear, a first-stage planet carrier, and a plurality of first-stage planet gears; the second-stage planetary gear set includes a second-stage sun gear, a second-stage ring gear, a second-stage planet carrier, and a plurality of second-stage planet gears; the third-stage planetary gear set includes a third-stage sun gear, a third-stage ring gear, a third-stage planet carrier, and a plurality of third-stage planet gears; the first-stage ring gear, the second-stage ring gear, and the third-stage ring gear are all fixedly connected to the housing;

[0038] In terms of transmission, the first-stage planet carrier of the first-stage planetary gear set is connected to the second-stage sun gear of the second-stage planetary gear set, the second-stage planet carrier of the second-stage planetary gear set is connected to the third-stage sun gear of the third-stage planetary gear set, and the third-stage planet carrier of the third-stage planetary gear set is connected to the drum;

[0039] The first-stage sun gear serves as the power input element, and the third-stage planet carrier serves as the power output element.

[0040] The electric winch of the present invention can automatically switch between different working conditions of no-load rope release and load operation without manual intervention, effectively reducing the working intensity and improving the working efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of an electric winch for improving the release speed of a pulling element according to an embodiment of the present invention;

[0042] Figure 2 Partial perspective view of an electric winch for improving the release speed of a pulling element according to an embodiment of the present invention;

[0043] Figure 3 Schematic diagram of the power input element (first-stage sun gear) according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0044] The exemplary embodiments of the present invention will be described in detail below with reference to the drawings, where the same or similar reference numerals represent the same or similar elements. Additionally, in the following detailed description, for the purpose of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments disclosed herein. However, it is obvious that one or more embodiments can be implemented without these specific details. In other cases, well-known structures and devices are illustrated in a schematic manner to simplify the drawings.

[0045] The present invention provides an electric winch with improved release speed of pulling element, which can increase the speed of releasing rope. Specifically, it ensures that the electric winch can work normally by keeping the transmission mechanism when the electric winch is performing load pulling work, and disconnects the transmission mechanism when releasing rope without load, that is, the rotation of the drum is disengaged from the actuator (such as a motor), so that the drum can rotate freely instead of being driven by the motor to release the rope, thereby speeding up the rotation and speeding up the rope release. It should be noted that if the two are not disengaged, but the rope is released by the motor, the rotation speed of the drum will be very slow due to the speed change of the motor through the speed change assembly (reduction mechanism), so the rope release speed is very slow, but this is not the case with the electric winch of the present invention.

[0046] The electric winch mainly consists of an actuator 5, a transmission and braking device 4, a transmission shaft 3, a speed change assembly 1, a drum 2, an end cover 6 and a housing 7. The actuator 5 usually exists in the form of a motor and is the power source for the electric winch to achieve traction. The transmission and braking device 4 is connected to the actuator 5 in a transmission manner, which is used to transmit the driving force of the actuator 5 and can achieve braking under predetermined conditions, such as emergency braking. One end of the transmission shaft 3 is connected to the transmission and braking device 4. The speed change assembly 1 includes a power input element and a power output element, which is used to achieve speed change and mainly plays a deceleration role. It can also be called a deceleration mechanism. The other end of the transmission shaft 3 interacts with the power input element. The drum 2 is connected to the power output element of the speed change assembly 1, the pulling element is wound on the drum 2, and most of the transmission shaft 3 is located inside the drum 2. The end cover 6 and the housing 7 constitute the outer shell of the electric winch, which surrounds the outer side of the speed change assembly 1 and supports the speed change assembly 1.

[0047] In a specific embodiment of the present invention, the speed change assembly 1 is designed to include a three-stage planetary gear set, including a first-stage planetary gear set, a second-stage planetary gear set and a third-stage planetary gear set; the first-stage planetary gear set includes a first-stage sun gear 101, a first-stage ring gear, a first-stage planet carrier and a plurality of first-stage planetary gears; the second-stage planetary gear set includes a second-stage sun gear, a second-stage ring gear, a second-stage planet carrier and a plurality of second-stage planetary gears; the third-stage planetary gear set includes a third-stage sun gear, a third-stage ring gear, a third-stage planet carrier and a plurality of third-stage planetary gears; the first-stage ring gear, the second-stage ring gear and the third-stage ring gear are all fixedly connected to the housing; in terms of transmission, the first-stage planet carrier of the first-stage planetary gear set is connected to the second-stage sun gear of the second-stage planetary gear set, the second-stage planet carrier of the second-stage planetary gear set is connected to the third-stage sun gear of the third-stage planetary gear set, and the third-stage planet carrier of the third-stage planetary gear set is connected to the drum 2; here, the first-stage sun gear 101 serves as the power input element, and the third-stage planet carrier serves as the power output element.

[0048] In this way, the rotation of the actuator 5 is transmitted to the drum 2 via three-stage transmission and three-stage reduction.

[0049] To achieve the object of the present invention, the electric winch is configured such that when the pulling element is being wound up, the other end of the transmission shaft 3 is engaged with the power input element, and when the pulling element is being released under no load, the other end of the transmission shaft 3 is disengaged from the power input element. Specifically, a transmission disk 10, a plurality of locking blocks 9 and a restraint element 8 are added to the electric winch, see Figure 2 , Figure 2 shows the inside of the end cover 6. Here, for the three-stage planetary gear set, only the first-stage sun gear 101 and the ring gear (the ring gear is located inside the end cover 6) of the first-stage planetary gear set are shown, and the other elements of the first-stage planetary gear set, as well as the second-stage and third-stage planetary gear sets, are not shown. The housing 7 and the drum 2 are also omitted in Figure 2 . As shown in the figure, the transmission disk 10 is fixedly arranged on the other end of the transmission shaft 3. A plurality of locking blocks 9 are hinged on the transmission disk 10 and are configured to be able to extend or retract relative to the center of the transmission disk 10. Preferably, the plurality of locking blocks 9 are strip-shaped. One ends of the plurality of locking blocks 9 are respectively hinged at positions near the outer periphery on the side surface of the transmission disk 10, and the other ends of the plurality of locking blocks 9, as free ends, can extend or retract relative to the center of the transmission disk 10. The plurality of locking blocks 9 are circumferentially symmetrically distributed relative to the center of the transmission disk 10. Advantageously, the number of the locking blocks 9 is three. As Figure 2 shown, a plurality of recessed spaces are provided in the side surface of the transmission disk 10, and the locking blocks 9 are arranged in the recessed spaces. One approximately tangentially arranged locking block 9 is installed in each recessed space.

[0050] Here, the first-stage sun gear 101 is sleeved on the transmission shaft 3, but the first-stage sun gear 101 is not fixedly connected to the transmission shaft 3 and can rotate around the transmission shaft 3 relative to the transmission shaft 3. The first-stage sun gear 101 is composed of a disk and a sun gear. The first-stage sun gear 101 includes a central hole provided at the center of the first-stage sun gear 101 for the transmission shaft 3 to pass through. The central hole passes through the centers of the disk and the sun gear. The first-stage sun gear 101 is positioned and supported by being clamped by a plurality of first-stage planet gears.

[0051] See Figure 3 . A plurality of grooves are provided on the power input element (the first-stage sun gear 101), and the power input element is configured such that when the locking blocks 9 are in the state of extending relative to the center of the transmission disk 10, they can extend into the grooves so that the transmission disk 10 and the power input element rotate simultaneously, and when in the state of retracting relative to the center of the transmission disk 10, they do not extend into the grooves, thereby causing the transmission disk 10 and the power input element to rotate out of sync. In addition, the power input element further includes a concave portion, and the concave portion is a groove in a substantially disk shape and is located in the end face of the power input element facing the transmission disk 10, as Figure 3As shown, the drive disk 10 is at least partially received in the concave portion. Among them, a plurality of bosses are formed on the outer peripheral surface of the disk-shaped groove of the concave portion, and the grooves are formed between adjacent bosses to form a structure in which the bosses and the grooves are staggered.

[0052] As Figure 2 shown, the restraint element 8 is disposed on the inner end surface of the housing (end cover 6). The restraint element 8 includes: a base portion that contacts the inner end surface of the housing and is capable of rotating relative to the inner end surface; and a periphery extending from the outer periphery of the base portion toward the power input element, forming a receiving space. A plurality of teeth and a plurality of tooth grooves are provided on the periphery (see Figure 2 ). Among them, the drive disk 10 is located in the receiving space, and the other end of the lock block 9 is always located in the tooth groove. The teeth on the periphery of the restraint element 8 clamp the lock block 9 like a pawl; the shape of the lock block 9 is adapted to be able to extend or retract relative to the center of the drive disk 10 under the action of the restraint element 8. The lock block 9 is in a bent long strip shape, and the other end of the lock block 9 extends out of the circumferential surface of the drive disk 10. The restraint element 8 is installed on the inner end surface of the end cover 6. The back surface of the restraint element 8 contacts the inner surface of the end cover 6, or a friction pad is installed between the two. The restraint element 8 and the end cover 6 can rotate relative to each other. The restraint element 8 can be supported on the end cover 6 through the structure of a shaft and a shaft hole. For example, a shaft hole is provided on the end cover 6, and a shaft extends out of the outside of the base portion of the restraint element 8 and extends into the shaft hole, or a shaft is provided on the end cover 6 and a shaft hole is provided on the restraint element 8.

[0053] The groove width of the tooth groove on the restraint element 8 is greater than the end width of the lock block 9. The inner diameter of the restraint element 8 is close to the outer diameter of the drive disk 10. That is, the end portions of the lock block 9 extending out of the drive disk 10 are respectively inserted into the tooth grooves of the restraint element 8. And when the lock block 9 is in contact with the drive disk 10 (that is, the lock block 9 retracts), the maximum diameter dimension of the lock block 9 is smaller than the outer diameter dimension of the restraint element 8, but greater than the inner diameter dimension of the periphery of the restraint element 8. Therefore, the lock block 9 is stuck in the tooth groove and will not completely fall into the receiving space.

[0054] It should be noted that the restraint element 8 extends into the concave portion, and the outer diameter of the periphery of the restraint element 8 is smaller than the inner diameter of the boss of the concave portion. The restraint element 8 and the first-stage sun gear 102 are concentrically and coaxially arranged, that is, the restraint element 8 does not contact the first-stage sun gear 102. Moreover, the width of the groove between the bosses of the concave portion is greater than the width of the extending end of the lock block 9.

[0055] The working process of the electric winch for improving the release speed of the pulling element of the present invention is described below:

[0056] When no-load rope release is required, the user directly pulls the rope, causing the roller 2 to rotate, driving the corresponding movement of the speed-changing assembly 1 until the power input element of the speed-changing assembly 1 rotates, that is, the first-stage sun gear 101 rotates, making it rotate clockwise (as observed from the direction of the end cover in the attached Figure 2 figure). At this time, the locking block 9 is in the retracted position and presses against the transmission disk 10, so the outermost end of the locking block 9 retracts into the tooth groove of the restraint element 8 and does not contact the boss portion of the first-stage sun gear 101. The first-stage sun gear 101 can rotate freely. That is, when the user pulls the rope to release the rope, only the frictional torque of the speed-changing assembly 1 needs to be overcome. To make the locking block 9 press against the transmission disk 10, the actuator 5 can be operated to drive the transmission shaft 3 to rotate clockwise (as observed from the direction of the end cover in the attached Figure 2 figure). At this time, under the resistance of the restraint element 8, the outer end of the locking block 9 rotates around the hinge point and presses against the transmission disk 10.

[0057] When the actuator 5 operates to tow the rope, the transmission shaft 3 is driven to rotate counterclockwise through the transmission and braking device 4 (as observed from the direction of the end cover in the attached Figure 2 figure). At this time, the transmission disk 10 rotates counterclockwise, and the outer end of the locking block 9 is stuck in the tooth groove of the restraint element 8. There is resistance when the back surface of the restraint element 8 contacts the end cover 6. Therefore, when the transmission disk 10 rotates counterclockwise, the outer end of the locking block 9 is affected by the resistance and rotates around the hinge point between the locking block 9 and the transmission disk 10, that is, the outer end of the locking block 9 moves outward and inserts into the groove between the bosses of the first-stage sun gear 101. Therefore, the locking block 9 is stuck between the transmission disk 10 and the first-stage sun gear 101, and the transmission disk 10 drives the first-stage sun gear 101 to rotate, thereby driving the roller 2 to rotate and wind the rope.

[0058] The electric winch of the present invention can automatically switch between different working conditions of no-load rope release and load operation without manual intervention, effectively reducing the working intensity and improving the working efficiency.

[0059] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes can be made therein without departing from the principle and spirit of the present invention. The scope of application of the present invention is defined by the appended claims and their equivalents.

[0060] List of reference numerals:

[0061] 1 Speed-changing assembly

[0062] 2 Roller

[0063] 3 Transmission shaft

[0064] 4 Transmission and braking device

[0065] 5 Actuator

[0066] 6 End cover

[0067] 7 Housing

[0068] 8 Constraint element

[0069] 9 Lock block

[0070] 10 Driving disk

[0071] 101 First-stage sun gear.

Claims

1. An electric winch for improving the release speed of a pulling element, characterized in that: The electric winch comprises: Actuator (5); A transmission and braking device (4) is in transmission connection with the actuator (5) and is used to transmit the driving force of the actuator (5) and can achieve braking under predetermined conditions; A transmission shaft (3), one end of which is connected to a transmission and braking device (4); A speed change assembly (1) comprises a power input element and a power output element, the other end of the transmission shaft (3) interacting with the power input element; and A roller (2), the roller (2) being connected to a power output element of a speed change assembly (1), the pulling element being wound around the roller (2), The electric winch is configured such that the other end of the transmission shaft (3) is coupled to the power input element when the pulling element is tightened, and the other end of the transmission shaft (3) is disengaged from the power input element when the pulling element is released without load.

2. The electric winch for improving the release speed of the pulling element according to claim 1, characterized in that: The electric winch also includes: a transmission plate (10) fixedly arranged on the other end of the transmission shaft (3); and A plurality of locking blocks (9) are hinged on the transmission disk (10) and are configured to be able to extend or retract relative to the center of the transmission disk (10). The power input element is provided with a plurality of grooves, and the power input element is configured so that the locking block (9) can extend into the grooves when it is in a state of extending outward relative to the center of the transmission disc (10) so that the transmission disc (10) and the power input element rotate simultaneously, and does not extend into the grooves when it is in a state of retracting inward relative to the center of the transmission disc (10) so that the transmission disc (10) and the power input element rotate asynchronously.

3. The electric winch for improving the release speed of the pulling element according to claim 2, characterized in that: The power input element comprises: a center hole, disposed at the center of the power input element, for the transmission shaft (3) to pass therethrough; and An inner recessed portion, which is a substantially disc-shaped groove, is located in the end surface of the power input element facing the transmission disc (10), and the transmission disc (10) is at least partially accommodated in the inner recessed portion, A plurality of bosses are formed on the outer peripheral surface of the disc-shaped groove of the inner concave portion, and the grooves are formed between adjacent bosses to form a structure in which bosses and grooves are staggered.

4. The electric winch for improving the release speed of the pulling element according to claim 3, characterized in that: The plurality of locking blocks (9) are in the shape of long strips, one end of each of the plurality of locking blocks (9) is hinged to a position close to the outer periphery of the side surface of the transmission disk (10), and the other end of each of the plurality of locking blocks (9) is a free end capable of extending outward or retracting relative to the center of the transmission disk (10).

5. The electric winch for improving the release speed of the pulling element according to claim 4, characterized in that: A plurality of recessed spaces are arranged in the side surface of the transmission plate (10), and the locking blocks (9) are arranged in the recessed spaces.

6. The electric winch for improving the release speed of the pulling element according to claim 5, characterized in that: The electric winch also includes a housing, which surrounds the outside of the speed change assembly (1) and supports the speed change assembly (1).

7. The electric winch for improving the release speed of the pulling element according to claim 6, characterized in that: The electric winch further comprises a restraining element (8), wherein the restraining element (8) is arranged on the inner end surface of the housing, and the restraining element (8) comprises: a base that contacts the inner end surface of the housing and is rotatable relative to the inner end surface; and A peripheral edge extending from the outer periphery of the base toward the power input element forms a receiving space, and a plurality of teeth and a plurality of tooth grooves are arranged on the peripheral edge. Wherein, the transmission disc (10) is at least partially located in the accommodation space, and the other end of the locking block (9) is always located in the tooth groove; The shape of the locking block (9) is suitable for being able to extend or retract relative to the center of the transmission plate (10) under the action of the restraining element (8).

8. The electric winch for improving the release speed of the pulling element according to claim 7, characterized in that: The restraining element (8) extends into the inner recess, and the outer diameter of the periphery of the restraining element (8) is smaller than the inner diameter of the boss of the inner recess.

9. The electric winch for improving the release speed of the pulling element according to claim 6, characterized in that: The outer shell is composed of an end cover (6) and a shell (7).

10. The electric winch with improved release speed of the pulling element according to any one of claims 6 to 9, characterized in that: The speed change assembly (1) comprises a first-stage planetary gear set, a second-stage planetary gear set and a third-stage planetary gear set; The first-stage planetary gear set comprises a first-stage sun gear (101), a first-stage ring gear, a first-stage planet carrier and a plurality of first-stage planetary gears; the second-stage planetary gear set comprises a second-stage sun gear, a second-stage ring gear, a second-stage planet carrier and a plurality of second-stage planetary gears; the third-stage planetary gear set comprises a third-stage sun gear, a third-stage ring gear, a third-stage planet carrier and a plurality of third-stage planetary gears; the first-stage ring gear, the second-stage ring gear and the third-stage ring gear are all fixedly connected to the housing; In terms of transmission, the first-stage planet carrier of the first-stage planetary gear set is connected to the second-stage sun gear of the second-stage planetary gear set, the second-stage planet carrier of the second-stage planetary gear set is connected to the third-stage sun gear of the third-stage planetary gear set, and the third-stage planet carrier of the third-stage planetary gear set is connected to the roller (2); The first-stage sun gear (101) serves as the power input element, and the third-stage planet carrier serves as the power output element.

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