Novel robot joint
By setting the bearings in the robot joint to transmit bending moment and using hollow structure and sealing measures in the reducer, the problem of traditional industrial robot joint reducers bearing high bending moment and torque is solved, and joint rigidity and reducer life are improved. The risk of oil leakage.
Patent Information
- Application Number
- CN202420339705.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-23
- Publication Date
- 2025-02-18
- Estimated Expiration
- 2034-02-23
AI Technical Summary
The reducer of traditional industrial robot joints needs to bear high bending moment and torque, resulting in high rigidity requirements, difficult disassembly and assembly and maintenance, and there is a risk of oil leakage.
A new type of robot joint is designed, by providing a first bearing and a second bearing between the transposable and the base, the bending moment is transmitted to the base. The reducer only needs to provide torque to avoid bearing bending moment. At the same time, hollow structure and sealing measures are used to prevent oil leakage.
It effectively avoids the impact of bending moment on the speed reduction device during robot movement, improves joint rigidity and the life of the reducer, reduces the workload of disassembly and assembly and maintenance, and prevents oil leakage.
Smart Images
Figure CN222494341U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of industrial robot joint structures. Background Art
[0002] With the continuous development of robot technology, the application fields of industrial robots are becoming more and more extensive. The structure of the joints of traditional industrial robots is relatively complex. Generally, the reducer is connected through an external motor. The motor is exposed to the outside for a long time. In some application scenarios that require dust prevention, additional protective covers need to be added to the motor. The torque and bending moment of the robot are borne by the J1-axis reducer, which has high requirements for the rigidity of the reducer. The reducer is difficult to disassemble and maintain, and there is a risk of oil leakage in the reducer. Once oil leakage occurs, the reducer needs to be disassembled and reinstalled, which increases the workload. Utility Model Content
[0003] In view of the above problems, the utility model proposes a novel robot joint, which overcomes the defect that the torque and bending moment of the existing industrial robot are all borne by the reducer, which has high requirements for the reducer, and effectively avoids the influence of the bending moment generated during the movement of the robot on the reduction device.
[0004] The technical solution of the utility model is as follows: it comprises a base 4 and a rotating seat 1 rotatably connected to the base 4, wherein the rotating seat 1 is sleeved on the base 4, and a gap is left between the two;
[0005] A motor 7 and a reduction gear 8 are fixedly installed in the base 4 . The rotor of the motor 7 is fixedly connected to the input end of the reduction gear 8 , and the output end of the reduction gear 8 is connected to the swivel seat 1 via a spline.
[0006] Furthermore, a first bearing 2 and a second bearing 3 are coaxially arranged between the swivel seat 1 and the base 4. In this way, the bending moment of the robot on the joint can be transmitted to the base 4 through the first bearing 2 and the second bearing 3, and the bending moment is borne by the swivel seat 1 and the base 4. At the same time, the output end of the reducer is connected to the swivel seat 1 through a spline, leaving a gap in the radial direction, so the output end of the reducer is not subjected to force in the radial direction. Therefore, the reduction device 8 inside the base 4 only needs to provide a torque to drive the swivel seat 1 to rotate, and does not need to bear the bending moment generated by the robot, which effectively avoids the influence of the bending moment generated when the robot moves on the reduction device.
[0007] In addition, the rotor of the motor 7 is also connected to an encoder 6 and a brake 5 which are fixedly installed in the base 4. The brake 5, the encoder 6, the motor 7 and the reduction device 8 are all hollow structures.
[0008] The brake 5, encoder 6, motor 7 and reduction device 8 are coaxially arranged, and the shells of the four are fixedly connected to the base 4, and a hollow sleeve 10 is passed through the center of the four, so that the robot structure is more compact and it is more convenient to route the wires inside the hollow sleeve 10.
[0009] Specifically, the input and output ends of the reduction device 8 respectively have a reduction gear input shaft 24 and a reduction gear output shaft 28, and the motor 7 has a motor output shaft 9 fixedly connected to the rotor;
[0010] The reducer output shaft 28 is connected to the inner wall of the swivel seat 1 through a spline, and the motor output shaft 9 is sleeved on the reducer input shaft 24, and the two are fixedly connected.
[0011] In order to further avoid the hidden danger of oil leakage at the input and output ends of the reduction device 8, the present case also proposes the following sealing measures:
[0012] An O-ring 15 is provided between the motor output shaft 9 and the reducer input shaft 24, and a labyrinth oil seal 14 is provided between the motor output shaft 9 and the base 4, so that a closed oil chamber is formed between the housing of the reduction gear 8, the reducer input shaft 24, the motor output shaft 9 and the base 4; in this way, the leaked lubricating oil can be discharged through the oil drain port when necessary, and the oil drain port can be blocked by the oil plug 30 when the lubricating oil does not need to be discharged, which can effectively prevent the lubricating oil of the reduction gear 8 from leaking from the input end to contaminate and damage the motor 7 and other components.
[0013] An oil seal 16 is provided between the swivel seat 1 and the hollow sleeve 10, so that another closed oil chamber 2 is formed between the swivel seat 1, the hollow sleeve 10 and the reducer output shaft 28, which prevents the lubricating oil of the reduction device 8 from leaking from the output end.
[0014] The base 4 is provided with an oil drain port connected to the oil chamber 1, and an oil plug 30 is provided in the oil drain port.
[0015] In this case, the swivel seat 1 and the base 4 are connected by the first bearing 2 and the second bearing 3, so the reduction device 8 only needs to transmit torque to avoid the influence of the bending moment generated when the robot moves on the reduction device 8, thereby improving the joint rigidity and increasing the life and stability of the reducer.
[0016] In this case, the reduction device 8, the motor 7, the encoder 6, the brake 5 and their mounting parts are all hollow structures, and a hollow sleeve 10 is inserted therein. The hollow sleeve 10 is fixed to the lower mounting flange 11 by screws, so that the wiring harness pipeline of the robot can pass through the hollow sleeve 10 through the robot joints, making the structure more compact.
[0017] A new type of robot joint designed in this case can be used as a joint module for independent installation and testing, further reducing the number of disassembly, assembly and debugging during the robot installation process. After the joint module test is passed, the various joint components of the robot can be directly connected for easy installation. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 This is the structural principle diagram of this case.
[0019] Figure 2 This is the structural diagram of this case.
[0020] Figure 3 It is a schematic diagram of the implementation method of this case.
[0021] Figure 4 This is a schematic diagram of the internal structure of the reducer in this case.
[0022] Figure 5 It is a schematic diagram of the appearance structure of this case;
[0023] Figure 6 This is a schematic diagram of the connection between the output shaft of the reducer and the swivel seat in this case;
[0024] In the figure, 1 is a swivel seat; 2 is a first bearing; 3 is a second bearing; 4 is a base; 5 is a brake; 6 is an encoder; 7 is a motor; 8 is a speed reducer; 9 is a motor output shaft; 10 is a hollow shaft sleeve; 11 is a lower mounting flange; 12 is a brake mounting flange; 13 is a brake mounting column; 14 is a labyrinth oil seal; 15 is an O-ring; 16 is an oil seal; 17 is the first bearing of the reducer; 18 is a flange cover of the reducer housing; 19 is a reducer housing; 20 is a needle tooth; 21 is a needle tooth sleeve; 22 is a column pin; 23 is a column pin sleeve; 24 is a reducer input shaft; 25 is a second bearing of the reducer; 26 is a cylindrical roller bearing; 27 is a cycloidal wheel; 28 is a reducer output shaft; 29 is a third bearing of the reducer; 30 is an oil plug. DETAILED DESCRIPTION
[0025] In order to clearly illustrate the technical features of this patent, this patent is elaborated in detail below through a specific implementation method and in combination with its accompanying drawings.
[0026] Its principle is as follows Figure 1 As shown, it is composed of a swivel seat 1, a first bearing 2, a second bearing 3, a base 4, a brake 5, an encoder 6, a motor 7, a reduction device 8, etc.
[0027] The new robot joint is connected to the reduction device 8 through the output end of the motor 7, the shell of the reduction device 8 is fixed on the base 4, and the output end of the reduction device 8 is connected to the swivel 1 through a spline, so as to drive the rotation of the swivel 1. The stator of the motor 7 is fixed on the base 4, and the output end is connected to the encoder 6 and the brake 5, and the brake 5 is fixed on the base 4. The first bearing 2 and the second bearing 3 are connected between the swivel 1 and the base 4. The bending moment of the robot on the joint can be transmitted to the base 4 through the first bearing 2 and the second bearing 3, and the base 4 bears the bending moment. Therefore, the reduction device 8 only needs to provide the torque to drive the swivel 1 to rotate, and does not need to bear the bending moment generated by the robot, thereby improving the joint rigidity. In order to make the robot structure more compact and convenient for internal wiring, the new robot joint can adopt a hollow structure, and the brake 5, encoder 6, motor 7, reduction device 8, etc. can all adopt a hollow structure.
[0028] Furthermore, the structural diagram of the robot joint is as follows Figure 2 As shown, the reduction gear 8 may have different forms, including but not limited to RV reducer, harmonic reducer, planetary reducer, cycloid reducer, worm gear reducer, etc. The motor 7 can transmit torque to the swivel 1 through the reduction gear 8, and the swivel 1 is further connected to the next joint of the robot. The motor includes but is not limited to torque motor, servo motor, stepper motor, etc. The encoder 6 is installed at the output end of the motor 7 to detect the rotation direction, position, speed, etc. of the motor output shaft. The encoder includes but is not limited to absolute encoder, incremental encoder, etc. The brake 5 is connected to the rotor of the motor 7 to stop the rotation of the rotor in time, thereby stopping the rotation of the joint. The brake includes but is not limited to disc brake, friction brake, electromagnetic brake, etc.
[0029] The principle of this patent is described in detail below in conjunction with a specific motor 7, a reduction device 8, etc., which does not mean that the reduction device 8 can only have this type of form.
[0030] The robot joint proposed in this case is a hollow structure. The shell of the reduction device 8 is installed on the base 4 by screws. The reducer input shaft 24 is connected to the rotor of the motor 7 through the motor output shaft 9, and the stator of the motor 7 is fixed to the base 4. The brake 5 is connected to the rotor of the motor 7 through the brake mounting column 13, and the brake 5 is fixed to the lower mounting flange 11 through the brake mounting flange 12, and the lower mounting flange 11 is fixed to the base 4 by screws. The encoder 6 is fixed to the rotor of the motor 7 by screws. The reducer output shaft 28 of the reduction device 8 is connected to the swivel 1 by screws, and the swivel 1 is supported on the side wall of the base 4 by the first bearing 2 and the second bearing 3. In this way, as the rotor of the motor 7 rotates, it is transmitted to the reduction device 8 through the motor output shaft 9 and the reducer input shaft 24, and the swivel 1 is driven to rotate by the reducer output shaft 28.
[0031] In this case, the reducer input shaft 24 is connected to the motor output shaft 9 by screws, and the connection is sealed by an O-ring 15, so a closed oil chamber is formed between the reducer housing 19 of the reduction gear 8, the motor output shaft 9 and the base 4, and the leaked lubricating oil can be discharged through the oil drain port. When the lubricating oil does not need to be drained, the oil drain port can be blocked by an oil plug 30, which can effectively prevent the lubricating oil of the reduction gear 8 from leaking from the input end to pollute and damage the motor 7 and other components, wherein the motor output shaft 9 and the base 4 are sealed by a labyrinth oil seal 14. Similarly, the oil seal 16 is used to seal between the swivel seat 1 and the hollow shaft sleeve 10, so a closed oil chamber is formed between the swivel seat 1, the hollow shaft sleeve 10 and the reducer output shaft 28 to prevent the lubricating oil of the reduction gear 8 from leaking from the output end.
[0032] The reducer input shaft 24 of the reduction device 8 is a hollow eccentric shaft, and a cycloid wheel 27 is installed on each of the two eccentric bosses through a cylindrical roller bearing 26. The two ends of the pin tooth 20 are respectively fixed on the reducer housing flange cover 18 and the reducer housing 19, and a pin tooth sleeve 21 is respectively sleeved on the outer side of the pin tooth 20 to cooperate with the outer edge of the cycloid wheel 27. The pin 22 is fixed on the reducer output shaft 28. As the reducer input shaft 24 rotates, the reducer output shaft 28 is driven to rotate by inserting the pin 22 and the pin sleeve 23 of the cycloid wheel 27.
[0033] The reducer output shaft 28 is connected to the reducer housing flange cover 18 via the reducer first bearing 17, and is sealed at the connection by an oil seal; the reducer input shaft 24 is connected to the reducer housing 19 via the reducer second bearing 25, and is sealed at the connection by an oil seal; the reducer input shaft 24 is connected to the reducer output shaft 28 via the reducer third bearing 29, and is sealed at the connection by an oil seal.
[0034] Among the above, the structural form of this case includes a swivel seat, bearings, base, reducer, motor, encoder, brake, etc. As long as the transmission method and principle are the same, they are all within the protection scope of this patent.
[0035] The "swivel seat" and "base" mentioned above are not limited to the first joint of the robot. The "base" is connected to the relatively fixed end of the rotary joint, and the "swivel seat" is connected to the relatively moving end of the rotary joint.
[0036] The reduction device is not limited to the cycloid reducer mentioned in this embodiment, and can be in various forms, such as RV reducer, harmonic reducer, planetary reducer, worm reducer, etc. The motor is not limited to the frameless torque motor, and other motors that can meet the transmission requirements can be realized.
[0037] A closed oil chamber is formed between the reducer input shaft 24, the motor output shaft 9 and the base 4 to prevent oil leakage from the reducer 8 and ensure that even if oil leakage occurs in the reducer, it will not affect components such as the motor and encoder. In addition, an oil drain hole is opened on the base 4 to prevent oil leakage from the reducer 8, and the leaked lubricating oil can be discharged in time through the oil drain port on the base.
[0038] The base 4 and the swivel 1 are connected by two bearings. The bending moment received by the robot during movement is borne by the base 4 and the swivel 1. The reduction device 8 only needs to transmit the torque to the swivel 1 through the reducer output shaft 28, avoiding the reducer from bearing both torque and bending moment, thereby improving the joint rigidity and the life of the reducer.
[0039] There are many specific implementation ways of the utility model. The above is only the preferred implementation mode of the utility model. It should be pointed out that for ordinary technicians in this technical field, several improvements can be made without departing from the principle of the utility model, and these improvements should also be regarded as the protection scope of the utility model.
Claims
1. A new type of robot joint, characterized in that: It comprises a base (4) and a swivel seat (1) rotatably connected to the base (4), wherein the swivel seat (1) is sleeved on the base (4); A motor (7) and a reduction gear (8) are fixedly mounted in the base (4); the rotor of the motor (7) is fixedly connected to the input end of the reduction gear (8), and the output end of the reduction gear (8) is connected to the swivel seat (1) via a spline.
2. A novel robot joint according to claim 1, characterized in that: A first bearing (2) and a second bearing (3) which are coaxially arranged are provided between the swivel seat (1) and the base (4).
3. A novel robot joint according to claim 1, characterized in that: An encoder (6) and a brake (5) fixedly mounted in the base (4) are also connected to the rotor of the motor (7); the brake (5), the encoder (6), the motor (7) and the reduction device (8) are all hollow structures.
4. A novel robot joint according to claim 3, characterized in that: The brake (5), encoder (6), motor (7) and reduction device (8) are coaxially arranged, and the outer shells of the four are fixedly connected to the base (4), and a hollow shaft sleeve (10) passes through the center of the four.
5. A novel robot joint according to claim 1, characterized in that: The input and output ends of the reduction device (8) respectively have a reduction gear input shaft (24) and a reduction gear output shaft (28), and the motor (7) has a motor output shaft (9) fixedly connected to the rotor; The reducer output shaft (28) is connected to the inner wall of the swivel seat (1) via a spline, and the motor output shaft (9) is sleeved on the reducer input shaft (24), and the two are fixedly connected.
6. A novel robot joint according to claim 5, characterized in that: An O-ring (15) is provided between the motor output shaft (9) and the reducer input shaft (24), and a labyrinth oil seal (14) is provided between the motor output shaft (9) and the base (4), so that a closed oil chamber is formed between the housing of the reduction device (8), the reducer input shaft (24), the motor output shaft (9) and the base (4); An oil seal (16) is provided between the swivel seat (1) and the hollow shaft sleeve (10), so that another closed oil chamber 2 is formed between the swivel seat (1), the hollow shaft sleeve (10) and the output shaft (28) of the reducer.
7. A novel robot joint according to claim 6, characterized in that: An oil drain port connected to the oil chamber 1 is provided on the base (4), and an oil plug (30) is provided in the oil drain port.