Mechanical redundancy structure for servo motor

Abstract

The invention discloses a mechanical redundant structure for servo motors, which comprises a plurality of servo motors and a speed reducer, output shafts of the plurality of servo motors are simultaneously in transmission connection with a speed reducer input shaft of the speed reducer and finally output power through an output shaft of the speed reducer, and the plurality of servo motors are not provided with brakes. And when one motor does not work, the motor can be driven by other motors without influencing the overall use of the equipment. And through the redundancy design of the main motor and the standby motor, the equipment can be automatically switched when the motor or a driver thereof breaks down, the shutdown is avoided, and the reliability of the system is improved. Output shafts of the main motor and the standby motor are connected together in a precise mechanical mode, encoders of the main motor and the standby motor are indirectly connected together in the mode, drivers of the main motor and the standby motor can sense information such as positions and states of the motors, and in the switching process, the information such as the positions and the states does not need to be captured through additional sensors.

Description

Technical Field

[0001] The present invention relates to the technical field of servo motors, and in particular to a mechanical redundancy structure for servo motors. Background Art

[0002] As a core component in mechanical equipment, servo motors are often used as high-reliability standard components. However, the redundant design of servo motors in industrial equipment is currently mainly reflected in the improvement of safety factors. For example, when a mechanical device requires a 1kW servo motor, a 3kW servo motor is usually selected to provide sufficient margin. However, this approach is limited to improving motor performance and cannot fundamentally solve the problem of equipment downtime caused by failure of the servo motor or its driver.

[0003] Ultra-high reliability scenarios (such as automated production lines and mission-critical operations) require extremely high continuous operation capabilities of equipment. Once a servo motor or its driver fails, traditional solutions may cause the entire system to be unable to continue operating, seriously affecting the stability and efficiency of task completion. Therefore, simply increasing the power of the servo motor is not enough to meet high reliability requirements.

[0004] Traditional servo motor redundancy design lacks a hardware-level backup system. Once a motor or its driver fails, the system relies entirely on repairs to resume operation. Excessively increasing the safety factor of a single motor will lead to increased costs, while the efficiency of the equipment will not be significantly improved. Currently, few mechanical devices provide servo motor redundancy in hardware architecture, that is, in the event of a single servo motor or its driver failure, the backup motor can seamlessly take over the task. Summary of the invention

[0005] The purpose of the present invention is to provide a mechanical redundancy structure for a servo motor. By adding a spare servo motor and a matching mechanical structure design in key components, the equipment can still complete the current task in any single point failure situation, greatly improving the reliability and practicality of the equipment.

[0006] The present invention is implemented by adopting the following technical scheme: a mechanical redundant structure for a servo motor, characterized in that it includes multiple servo motors and reducers, the output shafts of the multiple servo motors are simultaneously transmission-connected to the reducer input shaft of the reducer and finally output power through the output shaft of the reducer, and the motors that are not in a working state among the multiple servo motors are driven by motors in other working states.

[0007] Furthermore, the multiple servo motors include a main motor and an auxiliary motor, and the main motor and the auxiliary motor are respectively meshed with the reducer gear on the output shaft of the main motor, the auxiliary drive gear on the output shaft of the auxiliary motor, and the reducer gear on the reducer input shaft.

[0008] Further, both the main motor and the auxiliary motor are powered on. Under normal circumstances, the main motor is in the working state, while the auxiliary motor is not working under normal circumstances. It is in the disabled state and is driven by the main motor.

[0009] Further, the multiple servo motors include a main motor and an auxiliary motor. A main drive synchronous pulley is arranged on the output shaft of the main motor, an auxiliary synchronous pulley is arranged on the output shaft of the auxiliary motor, and a reducer synchronous pulley is arranged on the input shaft of the reducer. The main drive synchronous pulley, the auxiliary synchronous pulley, and the reducer synchronous pulley are connected by a synchronous belt for transmission.

[0010] Further, under normal circumstances, both the main motor and the auxiliary motor work simultaneously. When one of the motors or its driver fails, the system will make it enter the disabled state, and the other motor will drive the synchronous belt to output power.

[0011] Further, the auxiliary synchronous pulley includes a driving cylinder, a floating synchronous pulley, a driven claw, a spacer ring, and a driving claw. The driving cylinder is installed on the output shaft of the auxiliary motor, and the driving claw is installed on the driving cylinder and locked to the output shaft of the auxiliary motor by screws, so that the driving claw, the driving cylinder, and the output shaft of the auxiliary motor are integrated. The floating synchronous pulley is sleeved on the bearing outside the driving cylinder, and the floating synchronous pulley can rotate relative to the driving cylinder. The floating synchronous pulley and the driven claw are integrated, and a spacer ring is installed between the driving claw and the driven claw, and the power of the driving claw is transmitted to the driven claw through the spacer ring.

[0012] Further, a small brake is also arranged on the input shaft of the reducer. This brake is used to prevent the input shaft of the reducer from rotating after the equipment is powered off and stopped. The braking torque of this brake is less than the rated torques of the main motor and the auxiliary motor. Even when the brake fails during braking, the main motor and the auxiliary motor can overcome the braking torque and continue to work.

[0013] A mechanical redundancy structure for a servo motor according to the present invention has the following beneficial effects: Improve reliability and fault tolerance: Through the redundant design of the main motor and the standby motor, it is ensured that the equipment can automatically switch when the motor or its driver fails, avoiding downtime and improving the reliability of the system.

[0014] Enhance operation stability: The encoders of the main motor and the standby motor are respectively connected to their own output shafts. The output shafts of the main motor and the standby motor are connected together by a precise mechanical method. The encoders of the main motor and the standby motor are also indirectly connected together in this way. The drivers of the main motor and the standby motor can perceive information such as the position and state of the motor. During the switching process, there is no need to capture information such as position and state through additional sensors, and the system still maintains precise and stable operation.

[0015] Energy - saving and efficient: The standby motor is only enabled when the main motor or its driver fails, reducing energy consumption and improving the economic efficiency of the system.

[0016] Quick switching and reduced downtime: The automatic switching mechanism ensures quick recovery in case of failure, reducing the equipment downtime.

[0017] Wide applicability: It can be widely applied to automated equipment requiring high reliability, with strong adaptability and scalability. Brief Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. The drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0019] Figure 1 It is a schematic structural diagram of Embodiment 1 of the present invention; Figure 2 It is a partial sectional schematic diagram of Embodiment 1 of the present invention; Figure 3 It is a schematic structural diagram of Embodiment 2 of the present invention; Figure 4 It is a schematic structural diagram of the secondary synchronous pulley in Embodiment 2 of the present invention In the figure, 1 - main motor, 2 - secondary motor, 3 - reducer, 4 - output shaft, 5 - tensioning pulley, 6 - synchronous belt, 11 - main motor output shaft, 12 - main drive gear, 13 - main drive synchronous pulley, 21 - secondary motor output shaft, 22 - secondary drive gear, 23 - secondary synchronous pulley, 31 - reducer input shaft, 32 - reducer gear, 33 - reducer synchronous pulley, 231 - drive cylinder, 232 - floating synchronous pulley, 233 - driven claw, 234 - spacer ring, 235 - drive claw. Detailed Description of the Embodiments

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated in the drawings here can be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] like Figures 1-4 As shown, a mechanical redundancy structure for a servo motor includes a main motor 1, an auxiliary motor 2 and a reducer 3. The output shafts of the main motor 1 and the auxiliary motor 2 are simultaneously connected to the input shaft of the reducer 3 and finally output power through the output shaft 4 of the reducer 3. Neither the main motor 1 nor the auxiliary motor 2 has a brake, and when one of the motors does not work, it can be driven by the other motor without affecting the overall use of the device.

[0023] In Embodiment 1, the main motor 1 and the auxiliary motor 2 are respectively meshed simultaneously through the main drive gear 12 on the main motor output shaft 11 and the auxiliary drive gear 22 on the auxiliary motor output shaft 21 and the reducer gear 32 on the reducer input shaft 31 .

[0024] During normal operation, the drivers of the main motor 1 and the auxiliary motor 2 are both powered on, wherein the main motor 1 is used normally, and the auxiliary motor 2 does not work under normal circumstances and is in a disconnected state. Since the auxiliary motor 2 is disconnected and has no brake, it can be rotated by the main motor 1 through the meshing of the "main drive gear 12 - reducer gear 32 - auxiliary drive gear 22". At this time, the main motor 1 transmits power through the "main drive gear 12 - reducer gear 32 - reducer input shaft 31 - reducer 3 - output shaft 4".

[0025] When the main motor 1 or its driver fails, the main motor 1 and the auxiliary motor 2 exchange roles, and the auxiliary motor 2 continues to drive the output shaft 4.

[0026] In Example 2, a main drive synchronous wheel 13 is provided on the main motor output shaft 11, a secondary synchronous wheel 23 is provided on the secondary motor output shaft 21, and a reducer synchronous wheel 33 is provided on the reducer input shaft 31. The main drive synchronous wheel 13, the secondary synchronous wheel 23, and the reducer synchronous wheel 33 are connected through a synchronous belt 6. Two tensioning wheels 5 are provided on the back of the synchronous belt 6 for tensioning the synchronous belt.

[0027] The auxiliary synchronous pulley 23 adopts a floating structure, including a driving cylinder 231, a floating synchronous pulley 232, a driven claw 233, a spacer ring 234 and a driving claw 235. The driving cylinder 231 is installed on the output shaft 21 of the auxiliary motor. The driving claw 235 is installed on the driving cylinder 231 and locked to the output shaft 21 of the auxiliary motor by screws, so that the driving claw 235, the driving cylinder 231 and the output shaft 21 of the auxiliary motor are integrated. The floating synchronous pulley 232 is sleeved on the bearing outside the driving cylinder 231. The floating synchronous pulley 232 can rotate relative to the driving cylinder 231. The floating synchronous pulley 232 and the driven claw 233 are integrated. A spacer ring 234 is installed between the driving claw 235 and the driven claw 233. The power of the driving claw 235 is transmitted to the driven claw 233 through the spacer ring 234. The spacer ring 234 is made of rubber material, which can absorb vibration and reduce impact.

[0028] There is a gap between the driven claw 233, the spacer ring 234 and the driving claw 235. When the output shaft 21 of the auxiliary motor is stationary (at this time, the driving claw 235 will not move either), because there is a gap between the driven claw 233, the spacer ring 234 and the driving claw 235, the driven claw 233 and the floating synchronous pulley 232 can rotate at a small angle.

[0029] During normal operation, the main motor 1 and the auxiliary motor 2 work simultaneously. Since the "speed-time curves" of the outputs of the main motor 1 and the auxiliary motor 2 are the same, and there is a small gap at the floating synchronous pulley 232, and the spacer ring 234 is made of soft rubber material, it can compensate for the "fault alarm" problem of the motor driver caused by the "speed-time curves" of the two servo motors not being strictly the same.

[0030] When a fault occurs in the main motor 1 or its driver, the system will cut off the enable of the main motor 1, and the auxiliary motor 2 will continue to drive the reduction gear synchronous pulley 33 to work. A small brake is also installed on the input shaft 31 of the reduction gear. When the entire system shuts down and powers off, the brake is in the braking state. During normal operation, the brake is in the open state. The braking torque of this brake is less than the rated torques of the main motor 1 and the auxiliary motor 2. Even when the brake fails and brakes, the main motor 1 and the auxiliary motor 2 can overcome the braking torque of the brake and continue to work.

[0031] In the above embodiments, the basic principles, main features and advantages of the present invention are described. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, any changes and modifications made by those skilled in the art should fall within the protection scope of the appended claims of the present invention.

Claims

1. A mechanical redundancy structure for a servo motor, characterized in that: The invention comprises a plurality of servo motors and a reducer (3), wherein the output shafts of the plurality of servo motors are simultaneously transmission-connected to the reducer input shaft (31) of the reducer (3) and finally output power through the output shaft (4) of the reducer (3), and the motors of the plurality of servo motors that are not in a working state are driven by the motors of other working states.

2. A mechanical redundancy structure for a servo motor according to claim 1, characterized in that: The plurality of servo motors comprise a main motor (1) and an auxiliary motor (2), wherein the main motor (1) and the auxiliary motor (2) are respectively meshed simultaneously with a reducer gear (32) on a reducer input shaft (31) through a main drive gear (12) on an output shaft of the main motor (1) and an auxiliary drive gear (22) on an output shaft of the auxiliary motor (2).

3. A mechanical redundancy structure for a servo motor according to claim 2, characterized in that: The main motor (1) and the auxiliary motor (2) are both in a powered-on state. The main motor (1) is normally in a working state, while the auxiliary motor (2) is normally not in a working state, and is in a disconnected enabled state, and is driven by the main motor (1).

4. A mechanical redundancy structure for a servo motor according to claim 1, characterized in that: The plurality of servo motors comprise a main motor (1) and an auxiliary motor (2); a main drive synchronous wheel (13) is arranged on the output shaft of the main motor (1); an auxiliary synchronous wheel (23) is arranged on the output shaft of the auxiliary motor (2); a reducer synchronous wheel (33) is arranged on the reducer input shaft (31); and the main drive synchronous wheel (13), the auxiliary synchronous wheel (23), and the reducer synchronous wheel (33) are connected by a synchronous belt (6).

5. A mechanical redundancy structure for a servo motor according to claim 4, characterized in that: The main motor (1) and the auxiliary motor (2) work simultaneously under normal circumstances. When one of the motors or its driver fails, the system causes it to enter a disconnected enabling state, and the other drives the synchronous belt (6) to output power.

6. A mechanical redundancy structure for a servo motor according to claim 4, characterized in that: The auxiliary synchronous wheel (23) comprises a driving cylinder (231), a floating synchronous wheel (232), a driven claw (233), a spacer ring (234) and a driving claw (235), wherein the driving cylinder (231) is mounted on the auxiliary motor output shaft (21) of the auxiliary motor (2), and the driving claw (235) is mounted on the driving cylinder (231) and is screwed to the auxiliary motor output shaft (21), so that the driving claw (235), the driving cylinder (231) and the auxiliary motor are in a state of being ... The output shaft of the machine (2) is connected as a whole; the floating synchronous wheel (232) is sleeved on the bearing outside the driving cylinder (231), the floating synchronous wheel (232) can rotate relative to the driving cylinder (231), the floating synchronous wheel (232) and the driven claw (233) are connected as a whole, and a spacer ring (234) is installed between the driving claw (235) and the driven claw (233), and the power of the driving claw (235) is transmitted to the driven claw (233) through the spacer ring (234).

7. A mechanical redundancy structure for a servo motor according to claim 4, characterized in that: The reducer input shaft (31) is also provided with a small brake, which is used to prevent the reducer input shaft from rotating after the equipment is powered off and shut down. The braking torque of the brake is less than the rated torque of the main motor (1) and the auxiliary motor (2). Even if the brake fails and brakes, the main motor (1) and the auxiliary motor (2) can overcome the braking torque and continue to work.

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