Highly integrated integrated joint module for collaborative robots

Abstract

A highly integrated, one-piece joint module for collaborative robots in the field of robotics technology includes a housing, a high-speed input shaft, a low-speed output flange shaft, a reducer, a drive motor, a brake, an encoder module, a driver, and cables. The front of the joint module is a reduction structure composed of a reducer, a high-speed input shaft, and a low-speed output flange shaft. The motor is located in the middle of the joint, with its rotor part interference-fitted to the high-speed input shaft. The brake is located in the rear of the joint, with its fixed part fixed to the motor housing and its moving part connected to the square wheel structure of the high-speed input shaft, gripping the brake friction pads during braking. The encoder module consists of high-speed and low-speed shaft encoders. The driver is located at the rear of the joint. In this invention, the high-speed and low-speed shaft inductive encoder rotors are coplanar and share a single encoder stator, greatly compressing the rear joint space. A limiting elastic tensioning structure is used to constrain the cables passing through the hollow joint, maintaining tension and placing them on the axis, significantly improving the stability of the collaborative robotic arm.

Description

Technical Field

[0001] The present invention relates to a joint module in the field of robot technology, in particular to a highly integrated one-piece joint module for a collaborative robot with wavy inner ribs and a high-speed encoder rotor coplanar with a low-speed encoder rotor. Background Art

[0002] With the development of science and technology, the field of industrial manufacturing has increasingly emphasized standardization and industrialization. In the production process, the use of robotic arms can reduce the demand for skilled workers in production operations while ensuring the stability of product quality. Cooperation with ordinary workers can effectively reduce production costs and greatly improve production efficiency. Based on this industry demand, collaborative robots have gradually emerged in various processing and assembly links. The joint module is the core hardware part of the collaborative robot, mainly composed of motors, reducers, brakes, encoders, and drivers. The stability, precision, cost, and various parameters of the joint module determine the performance upper limit of the collaborative robot, but the following problems are still common in the joint module.

[0003] Limited by the weight of the collaborative arm, a large amount of weight reduction in the joint module leads to insufficient structural rigidity, which in turn affects the accuracy of the collaborative robot arm; since the joints are designed as an integrated unit and the internal modules are designed separately, a large amount of space is wasted when stacking and the large air gap makes the thermal resistance extremely large, affecting the performance of continuous use; the internal hollow wiring structure makes it easy for the cables to be twisted inside the structure, and then pulled, resulting in damage to the terminals and wear on the outer skin; the combination of joints is cumbersome and the coordination accuracy is not high, which indirectly leads to reduced accuracy of the robot arm. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention proposes a highly integrated one-piece joint module for a collaborative robot. The rear encoder module in the joint of the present invention is highly integrated, and the high- and low-speed axis inductive encoder rotors are coplanar and share an encoder stator, which greatly compresses the rear joint space. At the same time, a limited elastic tensioning structure is adopted to constrain the cables passing through the hollow joint to maintain tension and place them on the axis. When twisted, the cable length is dynamically compensated, reducing the occurrence of abnormalities caused by internal cable wear, thereby greatly improving the stability of the collaborative robot arm.

[0005] The present invention is realized by the following technical scheme, which includes a joint housing, a high-speed input shaft, a low-speed output flange shaft, a harmonic reducer, a drive motor, an electromagnetic brake, an encoder module, a driver, a drive heat sink, a joint rear cover, and a cable; the joint housing as a whole is a T-shaped hollow structure, including a housing front port, a housing rear port, a housing side port, a positioning boss, and a wavy inner rib; the housing front port and the housing rear port are respectively arranged at the front and rear ends of the joint housing, and the housing side port is arranged on the side wall of the joint housing; the housing front port is used to connect with the next joint module, and the housing rear port is fixedly connected with the joint rear cover; the positioning boss is arranged at the housing side port to realize the whole joint. Positioning of the module; the wavy inner ribs extend backwards from the end position of the drive motor, the inner rib bosses have different heights, and there are threaded holes in the axial direction for fixing various fixed parts at the rear of the joint. The wavy inner ribs are used for centering and reserving wiring space; the high-speed input shaft is a hollow structure and passes through the center of the joint housing, a harmonic generator flexible bearing is arranged at the front end, an integrated square wheel is arranged at the rear end, and the encoder module is connected at the end; the low-speed output flange shaft structure includes a low-speed output flange and a low-speed output shaft, the low-speed output flange is located at the front end of the low-speed output shaft, and the low-speed output shaft passes through the central through hole of the high-speed input shaft; the front end of the high-speed input shaft is connected to the low-speed output flange through a harmonic reducer; The drive motor is arranged in the middle part of the joint housing, and the rotor part of the drive motor is fixed to the middle part of the high-speed input shaft; the electromagnetic brake is a dry single-plate electromagnetic brake, which is arranged in the middle and rear part of the joint housing, including a brake fixing part, a brake moving part, and a brake friction pad matching square hole; the rear end of the high-speed input shaft passes through the electromagnetic brake; the brake fixing part is fixed to the inner wall of the joint housing; the brake friction pad matching square hole is arranged on the brake moving part and matched with the integrated square wheel at the rear end of the high-speed input shaft; the encoder module includes a high-speed shaft adapter flange, a high-speed code disc flange, a high-speed encoder rotor, a low-speed code disc flange, a low-speed encoder rotor, and an encoder module stator. The high-speed encoder rotor is fixed together with the rear end of the high-speed input shaft through the high-speed code disc flange and the high-speed shaft adapter flange, and the low-speed encoder rotor is fixed together with the rear end of the low-speed output flange shaft through the low-speed code disc flange; the encoder module stator is fixed together with the inner wall surface of the joint housing, and the high-speed encoder rotor and the low-speed encoder rotor are coaxial and coplanar; the driver and the drive heat sink are both connected to the encoder module stator, and the drive heat sink is arranged at the rear of the driver to dissipate heat for the driver. The driver is used to receive external control instructions and perform closed-loop control on the drive motor; the cables are arranged in the joint housing, and the driver, encoder module stator, electromagnetic brake, and motor communicate with each other through cables.

[0006] Furthermore, in the present invention, the drive motor includes a motor stator winding, a motor rotor permanent magnet, a motor rotor sleeve, and a motor collector plate, and the motor stator winding and the motor collector plate are all fixed to the inner wall surface of the joint housing; the motor collector plate is arranged at the rear end of the motor stator winding for controlling the drive motor; the motor rotor permanent magnet is evenly arranged on the electronic rotor sleeve in the circumferential direction, and the electronic rotor sleeve is fixed to the middle part of the high-speed input shaft.

[0007] Furthermore, in the present invention, the harmonic reducer includes a harmonic reducer flexible wheel and a harmonic reducer rigid wheel. The fixed part of the harmonic reducer flexible wheel is fixed to the front end inner wall surface of the joint housing, and the harmonic reducer rigid wheel is axially and radially supported by the cross roller bearings in the harmonic reducer; the front end of the high-speed input shaft is connected to the harmonic reducer flexible wheel through the harmonic generator flexible bearing, and the harmonic reducer flexible wheel drives the harmonic reducer rigid wheel to rotate through harmonic deformation; the harmonic reducer rigid wheel is fixed to the low-speed output flange.

[0008] Furthermore, the present invention also includes a positioning pin hole, a quick-release groove, and a brake fixing flange. The positioning pin hole and the quick-release groove are all arranged on the low-speed output flange. The brake fixing flange is arranged at the rear end of the electromagnetic brake. The brake fixing part is fixed together with the inner wall surface of the joint housing through the brake fixing flange.

[0009] Furthermore, the present invention also includes a floating end deep groove ball bearing, a fixed end deep groove ball bearing, a shaft retaining spring, and a bearing retaining ring; the floating end deep groove ball bearing is arranged at the middle part of the high-speed input shaft, and is used to provide support for the floating end of the high-speed input shaft; the shaft retaining spring is arranged at the rear end of the floating end deep groove ball bearing, and is used to clamp the floating end deep groove ball bearing; the high-speed shaft adapter flange is fixedly connected to the rear end of the high-speed input shaft through threads, and the low-speed code disk flange is fixedly connected to the rear end of the low-speed output shaft through threads, and the fixed end deep groove ball bearing is arranged between the brake fixing flange and the high-speed shaft adapter flange; the bearing retaining ring is arranged at the rear end of the fixed end deep groove ball bearing, and is used to clamp the fixed end deep groove ball bearing.

[0010] High-speed shaft support adopts the typical fixed end / floating end configuration. The bearing group rotates at high speed under extremely light load for a long time. Since the internal clearance is not adjusted, the ball is prone to high-frequency vibration in the raceway, resulting in a reduced life. Therefore, a wave spring is used at the floating end for preload. The preload force is calculated using the following formula

[0011] F = kd

[0012] Where F is the preload force (kN), k is the empirical coefficient, and d is the bearing inner diameter (mm).

[0013] For small motors, the empirical coefficient is generally taken as (0.005, 0.01). If it is necessary to consider the damage caused by external vibration when stationary, the empirical coefficient should be 0.02. Since the bearing set consists of two bearings, one large and one small, and the inner diameters are not consistent, the preload should meet

[0014] 0.005D≤F≤0.01d

[0015] Where d is the inner diameter of the small bearing (mm) and D is the inner diameter of the large bearing (mm).

[0016] When using corrugated gaskets for axial preload, first test the relationship between the compression of the corrugated gasket and the preload force through experiments, and use the cubic relationship of the deflection curve to fit the curve to get the relationship, and the correct compression amount can be obtained by graphical interpretation. At the same time, the preload can also be adjusted by using an adjusting gasket on the corrugated gasket to further improve the rigidity and reduce the difficulty of processing.

[0017] Since the bearing set is fixed on the hollow shaft neck, its tolerance should be corrected using the correction factor. First calculate the hollow shaft diameter ratio c i =d i / d, and then calculate the bearing inner ring diameter ratio c e =d / d e If the average outer diameter of the inner ring cannot be determined, the following formula can be used to estimate

[0018]

[0019] According to c i With c e The value of the interference relationship diagram of the hollow shaft neck provided by the corresponding bearing supplier can be consulted. The required interference amount Δ can be obtained by graphical method. H Interference with solid shaft Δ S The proportional coefficient is used to further adjust the radial clearance.

[0020] Finally, considering the influence of thermal steady-state temperature rise on bearing clearance during operation, it can be calculated by the following relationship:

[0021] Δr temp =0.012ΔT·d m

[0022] In the formula, Δr temp (μm) is the clearance reduction caused by temperature difference, ΔT(K) is the temperature difference between the inner ring and the outer ring, d m =(d+D) / 2 is the average diameter of the bearing.

[0023] Furthermore, the present invention also includes a sealing decorative ring and a sealing rubber ring, which are arranged between the joint housing and the low-speed output flange to seal and decorate the joint module.

[0024] Furthermore, the present invention also includes a wiring limit baffle, which is arranged near the side port of the shell, and the edge of the wiring limit baffle is bonded with a limit elastomer with a cavity structure inside. The wiring limit baffle and the limit elastomer are both used to prevent the cable from being broken.

[0025] In the invention, the T-shaped joint housing is structurally fixed directly to the harmonic reducer flexible wheel, motor stator winding, brake fixing flange, encoder module stator, driver, and drive heat sink from front to back, and the accuracy is ensured by the matching relationship. The drive motor can be structurally divided into two parts: the stator and the rotor, wherein the stator part is composed of the motor stator winding and the motor collector plate, and the rotor part is composed of the motor rotor sleeve and the motor rotor permanent magnets attached thereto and evenly distributed circumferentially. The inner wall of the rear part of the T-shaped joint housing has a wavy inner rib structure, which starts to extend backward from the end position of the motor stator armature matching section, and the inner rib boss has different heights and has threaded holes in the axial direction for fixing various fixed parts at the rear of the joint. The function of the wavy internal ribs is to strengthen the ribs, so that the thickness of the thin wall is reduced, the weight is reduced, and the thermal resistance is reduced, and the strength and rigidity of the rear part of the shell are improved; the second is the wiring space, which is used for internal wiring in the middle and rear part, from the motor collector, brake to the driver, and external wiring between the joints to connect the cables to the driver; the third is the centering function. The internal structural parts adopt the shape of a wave wheel to obtain a higher centering accuracy than the external hanging ears, rectangular sections and other fixing methods. The front part of the high-speed input shaft is the elliptical cylinder of the wave generator of the harmonic reducer, and the output torque to the flexible bearing of the harmonic reducer is used to drive the flexible wheel deformation; the middle front part is matched with a deep groove ball bearing, which is the floating end support of the high-speed input shaft; the middle part is connected to the motor rotor sleeve by interference fit as the torque input; the middle and rear part has a square wheel structure that cooperates with the brake friction plate, and the last part has a threaded section to connect the high-speed shaft adapter flange. The front part of the low-speed output flange shaft is the output flange surface, which has a quick-release slot shaped like a keyhole. There are two locating pin holes on the output flange surface, which together with the locating boss at the bottom of the joint housing form a positioning function; the low-speed output flange shaft has a threaded section at the rear end of the shaft that is directly connected to the low-speed code disc flange.

[0026] In the present invention, the dry single-plate electromagnetic brake is fixedly connected to the joint housing by a brake fixing flange, and the square hole of the brake friction disc and the wheel structure above the high-speed input shaft form a matching transmission resistance torque. The encoder module is composed of two coplanar inductive encoder code disc rotors to form a rotor pair and an inductive encoder module stator; the rotors are respectively bonded to the high-speed and low-speed shaft code disc flanges, and then connected to the high-speed shaft adapter flange and the low-speed output shaft; in order to ensure that the axial and radial runout of the high-speed shaft adapter flange meet the requirements, a fixed-end deep groove ball bearing is used for error constraint. The driver and the encoder module stator are connected plate-to-plate, and the rear of the driver is a drive heat sink. The heat sink boss is attached to the power device with the help of a thermally conductive silicone pad to reduce thermal resistance, and the back of the boss has a heat dissipation fin feature to enhance the natural convection heat transfer effect. A wiring limit plate is installed at the lower part of the T-joint housing, and a limit elastomer with a cavity structure inside is bonded to the edge. When the joint rotation cable is twisted and shortened, the limit elastomer of the next joint is compressed and deformed, thereby compensating for the cable leading to the next joint to prevent the cable from being twisted and broken, and providing appropriate cable tensioning force so that the cable can be constrained to be located near the axis of the low-speed output flange shaft, reducing cable wear.

[0027] Compared with the prior art, the present invention has the following beneficial effects: the present invention highly integrates the encoder module in the middle and rear of the joint, and the high- and low-speed axis inductive encoder rotors are coplanar and share an encoder stator, which greatly compresses the rear joint space; the flange connection innovatively adopts a quick-release and quick-positioning structure, which makes disassembly and assembly more convenient, and optimizes the traditional radial connection to an axial connection, so that the bolt force is more reasonable and the process requirements are reduced; a limited elastic tensioning structure is adopted to constrain the cable passing through the hollow joint to maintain tension and place it on the axis, and dynamically compensate for the cable length when torsion occurs, reducing the occurrence of abnormalities caused by internal cable wear, greatly improving the stability of the collaborative robot arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 An exploded view of components of an embodiment of the present invention;

[0029] Figure 2 for Figure 1 A partial enlarged view of the low and medium speed output flange shaft;

[0030] Figure 3 for Figure 1 A partial enlarged view of the middle joint shell;

[0031] Figure 4 for Figure 1 A partial enlarged view of the middle drive motor;

[0032] Figure 5 for Figure 1 A partial enlarged view of the encoder module;

[0033] Figure 6 A longitudinal cross-sectional view of an embodiment of the present invention;

[0034] Figure 7 is a structural diagram of a joint housing in an embodiment of the present invention;

[0035] Figure 8 is a structural diagram of an encoder module in an embodiment of the present invention;

[0036] Fig. 9 A structural diagram of a high-speed input shaft and an electromagnetic brake in an embodiment of the present invention;

[0037] Fig.10 This is a cable routing diagram in an embodiment of the present invention;

[0038] Fig.11 is a structural diagram of a next joint in an embodiment of the present invention;

[0039] The numbers in the accompanying drawings are: 1. joint housing, 101. front port of the housing, 102. rear port of the housing, 103. side port of the housing, 104. positioning boss, 105. wavy inner ribs, 2. drive motor, 201. motor rotor permanent magnet, 202. motor rotor bushing, 203. motor collector plate, 204. motor stator winding, 3. high-speed input shaft, 301. flexible bearing of harmonic generator, 302. integrated square wheel, 4. flexible wheel of harmonic reducer, 5. rigid wheel of harmonic reducer, 6. low-speed output flange shaft, 601. positioning pin hole, 602. low-speed output flange, 603. low-speed output shaft, 604. quick-release slot, 7. brake fixing flange, 8. electromagnetic brake, 801. square hole for matching brake friction pad ,802, brake moving part, 803, brake fixed part, 9, high-speed shaft adapter flange, 10, high-speed code disk flange, 11, high-speed encoder rotor, 12, low-speed code disk flange, 13, low-speed encoder rotor, 14, encoder module stator, 15, driver, 16, driver heat sink, 17, joint back cover, 18, floating end deep groove ball bearing, 19, fixed end deep groove ball bearing, 20, shaft retaining spring, 21, bearing retaining ring, 22, sealing decorative ring, 23, sealing rubber ring, 24, wiring limit baffle, 25, limit elastic body, 26, cable, 27, next joint cable, 28, next joint housing, 29, next joint wavy inner rib, 30, next joint positioning boss, 31, next joint elastic body. DETAILED DESCRIPTION

[0040] The following is a detailed description of an embodiment of the present invention in conjunction with the accompanying drawings. This embodiment is based on the technical solution of the present invention and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiment.

[0041] Example

[0042] The present invention is as above Figures 1 to 10As shown, the present invention includes a joint housing 1, a housing front port 101, a housing rear port 102, a housing side port 103, a positioning boss 104, a wave-shaped inner rib 105, a drive motor 2, a motor rotor permanent magnet 201, a motor rotor sleeve 202, a motor collector plate 203, a motor stator winding 204, a high-speed input shaft 3, a harmonic generator flexible bearing 301, an integrated square wheel 302, a harmonic reducer flexible wheel 4, a harmonic reducer rigid wheel 5, a low-speed output flange shaft 6, a positioning pin hole 601, a low-speed output flange 602, a low-speed output shaft 603, a quick-release slot 604, and a brake Fixed flange 7, electromagnetic brake 8, brake friction pad matching square hole 801, brake moving part 802, brake fixed part 803, high-speed shaft adapter flange 9, high-speed code disc flange 10, high-speed encoder rotor 11, low-speed code disc flange 12, low-speed encoder rotor 13, encoder module stator 14, driver 15, drive heat sink 16, joint rear cover 17, floating end deep groove ball bearing 18, fixed end deep groove ball bearing 19, shaft retaining spring 20, bearing retaining ring 21, sealing decorative ring 22, sealing rubber ring 23, wiring limit baffle 24, limit elastomer 25, cable 26. The joint housing 1 is a T-shaped hollow structure as a whole, and the housing front port 101 and the housing rear port 102 are arranged at the front and rear ends of the joint housing 1 respectively, and the housing side port 103 is arranged on the side wall of the joint housing 1; the housing front port 101 is used to connect with the next joint module, and the housing rear port 102 is fixedly connected with the joint rear cover 17; the positioning boss 104 is arranged at the housing side port 103, which is used to realize the positioning of the entire joint module; the wavy inner rib 105 starts to extend backward at the end position of the drive motor 2, and the boss height of the wavy inner rib 105 is different. There are threaded holes in the axial direction for fixing various fixed parts of the rear part of the joint, and the wavy inner rib 105 is used for centering and reserving wiring space. The high-speed input shaft 3 is a hollow structure and passes through the center of the joint housing 1. The front end is arranged with a harmonic generator flexible bearing 301, and the rear end is arranged with an integrated square wheel 302. The low-speed output flange shaft 6 includes a low-speed output flange 602 and a low-speed output shaft 603. The front end of the low-speed output shaft 603 is fixed to the low-speed output flange 602, and the low-speed output shaft 603 passes through the hollow of the high-speed input shaft 3. The drive motor 2 is arranged in the middle part of the joint housing 1. The electromagnetic brake 8 is a dry single-plate electromagnetic brake, which is arranged in the middle and rear part of the joint housing 1, and includes a brake fixing part 803, a brake moving part 802, and a brake friction pad matching square hole 801. The rear end of the high-speed input shaft 3 passes through the electromagnetic brake 8; the brake fixing part 803 is fixed to the inner wall surface of the joint housing 1; the brake friction pad matching square hole 801 is arranged on the brake moving part 802, and matches with the integrated square wheel 302 at the rear end of the high-speed input shaft.The encoder module includes a high-speed shaft adapter flange 9, a high-speed code disc flange 10, a high-speed encoder rotor 11, a low-speed code disc flange 12, a low-speed encoder rotor 13, and an encoder module stator 14. The high-speed encoder rotor 11 is fixed to the rear end of the high-speed input shaft 3 through the high-speed code disc flange 10 and the high-speed shaft adapter flange 9, and the low-speed encoder rotor 13 is fixed to the rear end of the low-speed output shaft 603 through the low-speed code disc flange 12; the encoder module stator 14 is fixed to the inner wall surface of the joint housing 1, and the high-speed encoder rotor 11 and the low-speed encoder rotor 13 are coaxial and coplanar. The driver 15 and the drive heat sink 16 are both connected to the encoder module stator 14. The drive heat sink 16 is arranged at the rear of the driver 15 for dissipating heat for the driver 15, and the driver 15 is used to receive external control instructions. The cable 26 is arranged in the joint housing 1, and the driver 15, the encoder module stator 14, the electromagnetic brake 8, and the drive motor 2 communicate with each other through the cable.

[0043] The driving motor 2 includes a motor rotor permanent magnet 201, a motor rotor sleeve 202, a motor collector plate 203, and a motor stator winding 204. The motor stator winding 204 and the motor collector plate 203 are all fixed to the inner wall surface of the joint housing 1; the motor collector plate 203 is arranged at the rear end of the motor stator winding 204, and is used to control the driving motor 2; the motor rotor permanent magnet 201 is evenly arranged on the electronic rotor sleeve 202 in the circumferential direction, and the electronic rotor sleeve 202 is fixed to the middle part of the high-speed input shaft 3. The harmonic reducer includes a harmonic reducer flexwheel 4 and a harmonic reducer rigid wheel 5. The fixed part of the harmonic reducer flexwheel 4 is fixed to the front end inner wall surface of the joint housing 1, and the harmonic reducer rigid wheel 5 is axially and radially supported by the cross roller bearings in the harmonic reducer; the front end of the high-speed input shaft 3 is connected to the harmonic reducer flexwheel 4 through the harmonic generator flexible bearing 301, and the harmonic reducer flexwheel 4 drives the harmonic reducer rigid wheel 5 to rotate through harmonic deformation; the harmonic reducer rigid wheel 5 is fixed to the low-speed output flange 602.

[0044] The positioning pin hole 601 and the quick release groove 604 are arranged on the low-speed output flange 602, the brake fixing flange 7 is arranged at the rear end of the electromagnetic brake 8, and the brake fixing part 803 is fixed to the inner wall surface of the joint housing 1 through the brake fixing flange 7. The floating end deep groove ball bearing 18 is arranged in the middle part of the high-speed input shaft 3 to provide support for the floating end of the high-speed input shaft 3; the shaft retaining spring 20 is arranged at the rear end of the floating end deep groove ball bearing 18 to clamp the floating end deep groove ball bearing 18; the high-speed shaft adapter flange 9 is fixed to the rear end of the high-speed input shaft 3 through threads, the low-speed code disc flange 12 is fixed to the rear end of the low-speed output shaft 603 through threads, and the fixed end deep groove ball bearing 19 is arranged between the brake fixing flange 7 and the high-speed shaft adapter flange 9; the bearing retaining ring 21 is arranged at the rear end of the fixed end deep groove ball bearing 19 to clamp the fixed end deep groove ball bearing 19.

[0045] The sealing decorative ring 22 and the sealing rubber ring 23 are arranged between the joint housing 1 and the low-speed output flange 602 to seal and decorate the joint module. The wiring limit baffle 24 is arranged near the side port of the housing. The edge of the wiring limit baffle is bonded with a limit elastic body 25 with a cavity structure inside. The wire limit baffle 24 and the limit elastic body 25 are used to prevent the cable 26 from being pulled off.

[0046] This embodiment can also be connected with other joints, such as Fig.10 and Fig.11 As shown, the front end 101 of the housing is connected to the next joint housing 28, and the next joint housing 28 is provided with a next joint wavy inner rib 29 and a next joint positioning boss 30. The next joint wavy inner rib 29 is similar in structure to the wavy inner rib 105 in the present invention, and the next joint positioning boss 30 is also similar in structure to the positioning boss 104 in the present invention. A next joint elastic body 31 is arranged at the front end 101 of the housing, and the next joint cable 27 passes through the low-speed output shaft 603.

[0047] The working process of the present invention: Since the actual working logic of the joint is very complex and has many branches, only the general working process is selected here for explanation, which is divided into three parts: open-loop driving process, encoder full closed-loop process, and emergency braking process.

[0048] Open loop driving process:

[0049] The driver 15 receives control instructions output from the outside, and accordingly sends electrical signals to the motor stator winding 204 on the drive motor 2 through a three-phase power cable connected to the motor collector plate 203, thereby generating a vector magnetic field in the motor to drive the motor rotor permanent magnet 201 and the motor rotor sleeve 202 to achieve synchronous rotation.

[0050] The high-speed input shaft 3 is supported and centered by the floating end deep groove ball bearing 18 and the fixed end deep groove ball bearing 19 at the front and rear ends, and is interference-connected with the motor rotor sleeve 202. When the motor rotor sleeve 202 rotates, the high-speed input shaft is driven, and the torque is transmitted to the harmonic reducer flexwheel 4 through the harmonic generator flexible bearing 301 connected to the front end wave generator elliptical surface, forcing it to generate harmonic wave deformation.

[0051] The harmonic reducer rigid wheel 5 is supported axially and radially by the cross roller bearings in the reducer. The harmonic reducer flexible wheel 4 is fixedly connected to the front end of the housing 1 by bolts. The harmonic wave deformation of the flexible wheel causes the flexible wheel to mesh with the small teeth of the rigid wheel, and the speed reduction drives the harmonic reducer rigid wheel 5 to rotate, and drives the low-speed output flange shaft 6 to transmit torque outward.

[0052] Encoder full closed loop process:

[0053] The high-speed code disc flange 10 is connected to the high-speed shaft adapter flange 9 through a bolt group, and the high-speed shaft adapter flange 9 is threadedly connected to the high-speed input shaft 3, so as to realize the synchronous rotation of the high-speed code disc flange 10 and the high-speed input shaft 3, and reflect the absolute angular position in real time on the high-speed encoder rotor 11.

[0054] The low-speed code disc flange 12 is threadedly connected to the low-speed output flange shaft 6 to achieve synchronous rotation and reflect the absolute angular position on the low-speed encoder rotor 13 in real time.

[0055] The encoder module stator 14 is opposite to the high-speed encoder rotor 11 and the low-speed encoder rotor 13. The encoder module stator 14 and the joint housing 1 are fixed with a bolt group. The absolute positions of the high-speed input shaft 3 and the low-speed output flange shaft 6 are read in real time, and fed back to the driver 15 through the communication cable 26 for full closed-loop control.

[0056] Emergency braking process:

[0057] When the driver 15 receives an emergency braking signal through the external communication cable 26, it will send a braking electrical signal to the electromagnetic brake 8 through the brake communication cable 26, causing the brake to lock the brake friction plate, and through the hole 801 above the friction plate, cooperate with the integrated square wheel 302 on the high-speed input shaft 3 to transmit the braking torque to the high-speed input shaft 3 for braking, thereby braking the entire joint.

[0058] The above describes the specific operation mode of the present invention. It should be understood that the present invention is not limited to the above specific operation mode, and those skilled in the art can make various modifications or variations within the scope of the claims, which does not affect the essence of the present invention.

Claims

1. A highly integrated integrated joint module for a collaborative robot, characterized in that: Including joint housing, high-speed input shaft, low-speed output flange shaft, harmonic reducer, drive motor, electromagnetic brake, encoder module, driver, drive heat sink, joint rear cover, and cables; The joint housing is a T-shaped hollow structure as a whole, including a housing front port, a housing rear port, a housing side port, a positioning boss, and a wavy inner rib; the housing front port and the housing rear port are respectively arranged at the front and rear ends of the joint housing, and the housing side port is arranged on the side wall of the joint housing; the housing front port is used to connect with the next joint module, and the housing rear port is fixedly connected with the joint rear cover; the positioning boss is arranged at the housing side port, and is used to realize the positioning of the entire joint module; the wavy inner rib starts to extend backward from the end position of the driving motor, the inner rib boss has different heights, and has a threaded hole in the axial direction for fixing various fixed parts of the rear part of the joint, and the wavy inner rib is used for centering and reserving wiring space; The high-speed input shaft is a hollow structure and passes through the center of the joint housing, a harmonic generator flexible bearing is arranged at the front end, an integrated square wheel is arranged at the rear end, and the end is connected to the encoder module; The low-speed output flange shaft structure includes a low-speed output flange and a low-speed output shaft. The low-speed output flange is located at the front end of the low-speed output shaft, and the low-speed output shaft passes through the central through hole of the high-speed input shaft. The front end of the high-speed input shaft is connected to the low-speed output flange through a harmonic reducer. The drive motor is arranged in the middle part of the joint housing, and the rotor part of the drive motor is fixed to the middle part of the high-speed input shaft; The electromagnetic brake is a dry single-plate electromagnetic brake, which is arranged in the middle and rear part of the joint housing, and includes a brake fixing part, a brake moving part, and a brake friction pad matching square hole; the rear end of the high-speed input shaft passes through the electromagnetic brake; the brake fixing part is fixed to the inner wall surface of the joint housing; the brake friction pad matching square hole is arranged on the brake moving part and matched with the integrated square wheel at the rear end of the high-speed input shaft; The encoder module comprises a high-speed shaft adapter flange, a high-speed code disc flange, a high-speed encoder rotor, a low-speed code disc flange, a low-speed encoder rotor, and an encoder module stator. The high-speed encoder rotor is fixed to the rear end of the high-speed input shaft through the high-speed code disc flange and the high-speed shaft adapter flange, and the low-speed encoder rotor is fixed to the rear end of the low-speed output flange shaft through the low-speed code disc flange; the encoder module stator is fixed to the inner wall surface of the joint housing, and the high-speed encoder rotor is coaxial and coplanar with the low-speed encoder rotor; The driver and the driver heat sink are both connected to the encoder module stator. The driver heat sink is arranged behind the driver to dissipate heat for the driver. The driver is used to receive external control instructions and perform closed-loop control on the drive motor. The cables are arranged in the joint housing, and the driver, the encoder module stator, the electromagnetic brake, and the motor communicate with each other through the cables; The drive motor comprises a motor stator winding, a motor rotor permanent magnet, a motor rotor sleeve, and a motor collector plate, wherein the motor stator winding and the motor collector plate are both fixed together with the inner wall surface of the joint housing; the motor collector plate is arranged at the rear end of the motor stator winding for controlling the drive motor; the motor rotor permanent magnet is evenly arranged on the electronic rotor sleeve in the circumferential direction, and the electronic rotor sleeve is fixed together with the middle part of the high-speed input shaft; The harmonic reducer comprises a harmonic reducer flexwheel and a harmonic reducer rigid wheel. The fixing part of the harmonic reducer flexwheel is fixed to the front inner wall surface of the joint housing, and the harmonic reducer rigid wheel is axially and radially supported by the cross roller bearing in the harmonic reducer. The front end of the high-speed input shaft is connected to the harmonic reducer flexwheel through the harmonic generator flexible bearing, and the harmonic reducer flexwheel drives the harmonic reducer rigid wheel to rotate through harmonic deformation. The harmonic reducer rigid wheel is fixed to the low-speed output flange. It also includes a positioning pin hole, a quick release groove, and a brake fixing flange. The positioning pin hole and the quick release groove are arranged on the low-speed output flange. The brake fixing flange is arranged at the rear end of the electromagnetic brake. The brake fixing part is fixed to the inner wall surface of the joint housing through the brake fixing flange. It also includes a floating end deep groove ball bearing, a fixed end deep groove ball bearing, a shaft retaining ring, and a bearing retaining ring; the floating end deep groove ball bearing is arranged in the middle part of the high-speed input shaft, and is used to provide support for the floating end of the high-speed input shaft; the shaft retaining ring is used to axially position the floating end deep groove ball bearing; the high-speed shaft adapter flange is fixed to the rear end of the high-speed input shaft through threads, the low-speed code disk flange is fixed to the rear end of the low-speed output shaft through threads, and the fixed end deep groove ball bearing is arranged between the brake fixing flange and the high-speed shaft adapter flange; the bearing retaining ring is arranged at the rear end of the fixed end deep groove ball bearing, and is used to axially position the fixed end deep groove ball bearing; It also includes a sealing decorative ring and a sealing rubber ring; the sealing decorative ring and the sealing rubber ring are arranged between the joint housing and the low-speed output flange, and are used to seal and decorate the joint module; It also includes a wiring limit baffle, which is arranged near the side port of the shell. The edge of the wiring limit baffle is bonded to a limit elastic body with a cavity structure inside. The wiring limit baffle and the limit elastic body are both used to prevent the cable from being broken.

2. The highly integrated integrated joint module for a collaborative robot according to claim 1, characterized in that The floating end deep groove ball bearing adopts a wave spring or a corrugated gasket for axial preload; when a wave spring is adopted, the axial preload force is calculated by the following formula: F = kd In the formula, F is the preload force (kN), k is the empirical coefficient, and d is the bearing inner diameter (mm); For small motors, the empirical coefficient k is generally taken in the range of (0.005, 0.01). If damage caused by external vibration during stationary operation is to be considered, the empirical coefficient l should be 0.

02. At the same time, the preload force should satisfy: 0.005D≤F≤0.01d, where d is the inner diameter of the small bearing (mm) and D is the inner diameter of the large bearing (mm).

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