A small volume high rigidity explosion-proof robot joint module

Abstract

The application relates to the field of robot joint modules, and particularly discloses a small-size high-rigidity explosion-proof robot joint module which comprises a cycloid speed reducer, an explosion-proof shell, an explosion-proof rear shell, a brushless motor, a motor driver, an output end encoder, a cable introduction device, a motor encoder, a double-encoding rotating shaft and a cable leading-out device; the cycloid speed reducer, the explosion-proof shell and the explosion-proof rear shell form an explosion-proof cavity for accommodating electrical elements such as the brushless motor and the motor driver; the brushless motor stator is fixed to the bottom of the explosion-proof shell, and the rotor is connected with the cycloid speed reducer; the motor driver is embedded on the brushless motor stator, and the encoder carried by the motor driver is used for sensing the position information of the brushless motor rotor and the output end of the cycloid speed reducer; and the cable leading-out device and the cable introduction device are respectively installed on the double-encoding rotating shaft and the explosion-proof rear shell, so as to wrap the cables and meet the explosion-proof requirement. The application has the advantages of small size, high rigidity, high integration, high precision and the like while meeting the explosion-proof performance.

Description

Technical Field

[0001] This application relates to the field of robot joint modules, and in particular to a small-volume, high-rigidity explosion-proof robot joint module. Background Technology

[0002] As a core component of articulated robots, joint modules integrate reducers, motors, encoders, and drivers, significantly improving the modularity of robots and reducing development costs. With robot structures becoming increasingly compact and lightweight, higher demands are being placed on the quality and size of joint modules. From an explosion-proof design perspective, an excessively large internal cavity in an explosion-proof joint module means a higher energy release in the event of an explosion, necessitating more stringent explosion-proof design requirements. Therefore, miniaturization of explosion-proof joint modules is essential. However, while miniaturizing joint modules, maintaining transmission stiffness is often difficult due to the compactness of the internal joint structure. Therefore, ensuring both a small explosion-proof joint size and adequate transmission stiffness is a practically significant challenge. Summary of the Invention

[0003] In order to ensure both the small size of the explosion-proof joint and the explosion-proof performance, this application provides a small-sized, high-rigidity explosion-proof robot joint module.

[0004] The explosion-proof robot joint module with small volume and high rigidity provided in this application adopts the following technical solution:

[0005] A small-volume, high-rigidity explosion-proof robot joint module, comprising:

[0006] Explosion-proof enclosure with an internal cavity;

[0007] An explosion-proof rear shell is attached to the bottom of the explosion-proof outer shell;

[0008] A cycloidal reducer is installed on the top of the explosion-proof housing. The stator of the cycloidal reducer, the explosion-proof housing, and the explosion-proof rear housing form the stator of the joint module, and the rotor of the cycloidal reducer serves as the rotor of the joint module.

[0009] The cavity of the explosion-proof housing is provided with:

[0010] A brushless motor, wherein the stator of the brushless motor is fixed inside the explosion-proof housing, and the rotor of the brushless motor is connected to the input end of the cycloidal reducer;

[0011] A motor driver is fixed to the stator of the brushless motor, and the three-phase wires of the brushless motor are connected to the motor driver.

[0012] An output encoder, installed at the bottom of the motor driver, is used to obtain the position information of the output end of the cycloidal reducer;

[0013] A motor encoder, mounted on top of the motor driver, is used to obtain the position information of the brushless motor rotor;

[0014] A double-braided rotating shaft is fixed to the output end of the cycloidal reducer and is used to transmit the position information of the output end of the cycloidal reducer.

[0015] A cable entry device and a cable exit device are used to enter and exit the explosion-proof enclosure, respectively;

[0016] An explosion-proof joint structure is provided between the output end of the cycloidal reducer and the stator of the cycloidal reducer, between the double-braided shaft and the output end of the cycloidal reducer, between the cycloidal reducer and the explosion-proof housing, and between the explosion-proof rear housing and the explosion-proof housing for sealing and explosion-proof purposes.

[0017] The joint module provided in this application has a compact structure and explosion-proof function; it adopts a cycloidal reducer, which has higher rigidity and smaller size compared with the use of a harmonic reducer.

[0018] By employing dual encoders, the motor driver integrates the rotor position information of the brushless motor, the position information of the cycloidal reducer output, and the current information of the three-phase lines of the brushless motor to adjust the torque, speed, position, and status of the joint module, thereby achieving high-precision control of the joint module output.

[0019] The integrated brushless motor, cycloidal reducer, motor driver, explosion-proof housing, explosion-proof rear housing, and double-braided shaft are modularly replaceable, facilitating assembly and maintenance.

[0020] Furthermore, the cycloidal reducer includes a reducer upper housing and a reducer lower housing that are mated to each other, and a transmission mechanism disposed between the two; the output end of the transmission mechanism is connected to an output flange, and the double-braided shaft is fixedly connected to the output flange.

[0021] The upper and lower housings of the reducer form a stable transmission cage structure, eliminating the transmission cantilever structure and providing excellent radial force resistance while also having good resistance to axial force.

[0022] Furthermore, an upper swing wheel washer is provided between the transmission mechanism and the upper housing of the reducer, and a lower swing wheel washer is provided between the transmission mechanism and the lower housing of the reducer.

[0023] Upper and lower balance wheel washers help reduce surface wear on the upper and lower housings of the reducer during high-torque transmission, thus preventing transmission failures.

[0024] Furthermore, a plurality of pin teeth are evenly distributed between the upper and lower housings of the reducer, and pin teeth are sleeved on the pin teeth; the transmission mechanism includes an upper cycloidal wheel and a lower cycloidal wheel with staggered teeth, both of which mesh with the pin teeth; the input end of the transmission mechanism includes an eccentric assembly for driving the upper and lower cycloidal wheels to rotate, and the output end of the transmission mechanism includes a plurality of output rollers and an output screw passing through the output rollers, the output rollers being rotatably disposed in the through holes of the upper and lower cycloidal wheels, and the output screw being fixedly connected to the output flange.

[0025] Furthermore, the eccentric assembly includes an upper eccentric shaft rotatably disposed on the inner ring of the upper cycloidal wheel and a lower eccentric shaft rotatably disposed on the inner ring of the lower cycloidal wheel. The upper eccentric shaft and the lower eccentric shaft are symmetrically arranged at 180° and are connected by a plurality of eccentric shaft fixing pins. The upper eccentric shaft and the lower eccentric shaft are connected together by an eccentric shaft adapter.

[0026] The precision of the eccentric component (the size of the eccentricity, the precision of 180° symmetry) has a significant impact on the transmission accuracy and efficiency of the cycloidal reducer. The difficulty in manufacturing a cycloidal reducer lies in the machining of the eccentric component (eccentric shaft). The input eccentricity of industrial cycloidal reducers is mostly generated by eccentric sleeve bearings, but the limited models, large size, and low eccentricity precision of eccentric sleeve bearings restrict the design of small cycloidal reducers.

[0027] This application uses two identical eccentric shafts symmetrically arranged, and uses eccentric shaft fixing pins to ensure the eccentricity accuracy of the upper and lower eccentric shafts, which greatly reduces the difficulty of processing and improves the eccentricity accuracy.

[0028] Furthermore, a ring of upper bearing pins is densely distributed between the outer ring of the upper eccentric shaft and the inner ring of the upper cycloidal wheel, and a ring of lower bearing pins is densely distributed between the outer ring of the lower eccentric shaft and the inner ring of the lower cycloidal wheel; the upper eccentric shaft and the lower eccentric shaft are respectively fixedly connected with an upper bearing pin limiting plate and a lower bearing pin limiting plate; the inner rings of the upper cycloidal wheel and the lower cycloidal wheel are each provided with a flange; the upper bearing pin limiting plate and the inner ring flange of the upper cycloidal wheel are used to limit the two ends of the upper bearing pin, and the lower bearing pin limiting plate and the inner ring flange of the lower cycloidal wheel are used to limit the two ends of the lower bearing pin.

[0029] The bearings in cycloidal reducers are a major factor limiting their miniaturization. Because cycloidal reducers use an eccentric input method, significant stress is generated at the eccentric shaft. This stress is sufficient to crush ordinary bearings during high-torque transmission. Bearings with sufficient radial load capacity are often large in size (wall thickness, bearing thickness) and have limited allowable speeds. This application uses densely arranged bearing pins and limiting plates to achieve the effect of a bearing, enabling higher speeds under grease lubrication.

[0030] Furthermore, the outer ring of the eccentric shaft adapter is rotatably connected to an eccentric shaft positioning bearing, which is used to provide centering for the upper and lower eccentric shafts; the eccentric shaft positioning bearing is rotatably connected to an output parallel connector, which is provided with a through hole for the output screw to pass through.

[0031] Furthermore, an upper limit gasket is provided between the output roller and the output flange, and a lower limit gasket is provided between the output roller and the output parallel component.

[0032] Upper and lower limit shims are used to position the output rollers and reduce wear during transmission.

[0033] The output screw passes through the through hole on the output parallel component, then passes through the lower limit washer, the output roller, and the upper limit washer in sequence, and finally connects to the output flange. After deceleration, the cycloidal reducer drives the output screw through the output roller, which in turn drives the output flange to rotate, thus completing the power transmission.

[0034] Furthermore, the explosion-proof joint structure is a socket joint structure or a stop joint structure.

[0035] The socket-type or stop-type joint structure ensures that the explosion-proof joint surface has a sufficiently long width and a sufficiently small gap to prevent the explosion flame from escaping from the casing.

[0036] This application also provides an explosion-proof robot, including a small-volume, high-rigidity explosion-proof robot joint module.

[0037] The joint module provided in this application facilitates the modular design of explosion-proof robots and is easy to assemble into explosion-proof robots with different structures.

[0038] In summary, this application includes at least one of the following beneficial technical effects:

[0039] 1. The robot joint module provided in this application uses a cycloidal reducer, which has higher rigidity and smaller size compared to using a harmonic reducer;

[0040] 2. The cycloidal reducer in this application uses an eccentric shaft with bearing pins. Compared with the eccentric sleeve bearings used in common industrial cycloidal reducers, the cycloidal reducer provided in this application has a smaller volume, higher eccentricity accuracy and lower processing difficulty. The thickness of the cycloidal reducer can be as thin as 10mm, which is more suitable for the assembly of small robot joints.

[0041] 3. The robot joint module provided in this application has an outer diameter of ≤122mm and an axial length of ≤70mm, and has a small volume in both the radial and axial directions;

[0042] 4. The robot joint module provided in this application has dual encoders, which can ensure high-precision control at the output end of the explosion-proof joint module;

[0043] 5. The robot joint module provided in this application adopts a hollow layout with cable lead-out and lead-in devices, which facilitates cable arrangement when multiple explosion-proof joint modules are used in series.

[0044] 6. The brushless motor, cycloidal reducer, motor driver, explosion-proof housing, explosion-proof rear housing, and double-braided shaft integrated in this application are modularly replaceable, which facilitates assembly and maintenance; it also facilitates the modular design of explosion-proof robots and makes it easy to assemble explosion-proof robots with different structures. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the overall structure of the joint module in the embodiments of this application;

[0046] Figure 2 This is a cross-sectional view of the joint module in an embodiment of this application;

[0047] Figure 3 This is an exploded structural diagram of the joint module in an embodiment of this application;

[0048] Figure 4 This is a schematic diagram of the explosion-proof mating surface of the joint module in an embodiment of this application;

[0049] Figure 5 This is an exploded structural diagram of the cycloidal reducer in the embodiments of this application;

[0050] Figure 6 This is an exploded structural diagram of the transmission mechanism in the cycloidal reducer in the embodiments of this application.

[0051] Reference numerals: 1. Cycloidal reducer; 2. Explosion-proof housing; 3. Explosion-proof rear housing; 4. Brushless motor; 5. Motor driver; 6. Output encoder; 7. Cable entry device; 8. Motor encoder; 9. Double-braided shaft; 10. Cable exit device; 11. Explosion-proof mating surface one; 12. Explosion-proof mating surface two; 13. Explosion-proof mating surface three; 14. Explosion-proof mating surface four; 21. Output flange; 22. Upper crossed roller bearing; 23. Reducer upper housing; 24. Upper swing wheel washer; 25. Transmission mechanism; 26. Lower swing wheel washer; 27. 28. Lower housing of the reducer; 29. ​​Fixing screw; 30. Eccentric shaft adapter; 31. Lower crossed roller bearing; 32. Eccentric shaft positioning bearing; 33. Output parallel connector; 34. Output screw; 35. Upper bearing pin limiting plate; 36. Eccentric shaft fixing pin; 37. Upper bearing pin; 38. Upper cycloidal wheel; 39. Upper limit shim; 40. Output roller; 41. Lower limit shim; 42. Lower cycloidal wheel; 43. Lower bearing pin; 44. Lower eccentric shaft; 45. Lower bearing pin limiting plate; 46. Needle tooth; 47. Needle tooth pin. Detailed Implementation

[0052] The following is in conjunction with the appendix Figure 1-6 This application will be described in further detail.

[0053] This application discloses a small-volume, high-rigidity explosion-proof robot joint module. (Refer to...) Figure 1 and Figure 2 The small-volume, high-rigidity explosion-proof robot joint module includes an explosion-proof housing 2, with an internal cavity. An explosion-proof rear housing 3 is connected to the bottom of the explosion-proof housing 2 via screws, and a cycloidal reducer 1 is mounted on the top of the explosion-proof housing 2. The stator of the cycloidal reducer 1, the explosion-proof housing 2, and the explosion-proof rear housing 3 constitute the stator of the joint module, while the rotor of the cycloidal reducer 1 serves as the rotor of the joint module. The stator of the cycloidal reducer 1 and the explosion-proof rear housing 3 are provided with threaded holes for fixing the explosion-proof joint module, and the output end of the cycloidal reducer 1 is provided with threaded holes for connecting to external mechanisms.

[0054] Reference Figure 2 and Figure 3 A brushless motor 4 is installed inside the cavity of the explosion-proof housing 2. The stator of the brushless motor 4 is fixed inside the explosion-proof housing 2, and the rotor of the brushless motor 4 is connected to the input end of the cycloidal reducer 1. A motor driver 5 is fixed in the groove of the stator of the brushless motor 4, and the three-phase wires of the brushless motor 4 are connected to the top of the motor driver 5.

[0055] Reference Figure 2 and Figure 3An output encoder 6 is mounted on the bottom of the motor driver 5 to obtain the position information of the output end of the cycloidal reducer 1; a motor encoder 8 is mounted on the top of the motor driver 5 to obtain the position information of the rotor of the brushless motor 4. A double-braided shaft 9 is mounted on the output end of the cycloidal reducer 1 to transmit the position information of the output end of the cycloidal reducer 1.

[0056] Reference Figure 2 and Figure 3 A cable lead-out device 10 is provided at the center hole of the double-braided shaft 9. The cable led out is used to power and communicate with the next explosion-proof joint module or electrical equipment. A cable entry device 7 is provided at the center hole of the explosion-proof rear shell 3. The cable entered is used to power and communicate with the motor driver 5. Both the cable lead-out device 10 and the cable entry device 7 use explosion-proof filler to tightly wrap the cable to achieve the explosion-proof effect.

[0057] The joint module provided in this application has a compact structure and explosion-proof function. The cycloidal reducer 1 used in the joint module has more contact points during transmission and does not contain flexible parts such as flexure wheels, thus having high rigidity and a smaller volume compared to traditional harmonic reducers.

[0058] By employing dual encoders, the motor driver 5 integrates the rotor position information of the brushless motor 4, the position information of the output end of the cycloidal reducer 1, and the current information of the three-phase lines of the brushless motor 4 to adjust the torque, speed, position, and state of the joint module, thereby achieving high-precision control of the joint module output end.

[0059] The integrated brushless motor 4, cycloidal reducer 1, motor driver 5, explosion-proof housing, explosion-proof rear housing, and double-braided shaft 9 can be modularly replaced for easy assembly and maintenance.

[0060] Reference Figure 2 and Figure 4 A socket-type explosion-proof mating surface 11 is provided between the output end of the cycloidal reducer 1 and the stator of the cycloidal reducer 1, with a minimum radial clearance ≥0.05mm, a maximum clearance ≤0.25mm, and a socket bend length ≥35mm. A stop-type explosion-proof mating surface 12 is provided between the double-rotating shaft 9 and the output end of the cycloidal reducer 1, a stop-type explosion-proof mating surface 13 is provided between the stator of the cycloidal reducer 1 and the explosion-proof housing 2, and a stop-type explosion-proof mating surface 14 is provided between the explosion-proof rear housing 3 and the explosion-proof housing 2; the clearance of each stop-type explosion-proof mating surface is ≤0.1mm, and the width of the explosion-proof mating surface is ≥12.5mm.

[0061] The socket-type or stop-type joint structure ensures that the explosion-proof joint surface has a sufficiently long width and a sufficiently small gap to prevent explosion flames from escaping from the enclosure. Furthermore, the wall thickness of the explosion-proof enclosure 2 is ≥8mm, which can prevent the gap of the explosion-proof joint surface from increasing due to enclosure deformation caused by an explosion, thereby preventing the failure of the explosion-proof joint surface.

[0062] Reference Figure 5 The cycloidal reducer 1 includes a reducer upper housing 23 and a reducer lower housing 27 that are mated to each other, and a transmission mechanism 25 disposed between the two. An upper cycloidal wheel washer 24 is disposed between the transmission mechanism 25 and the reducer upper housing 23, and a lower cycloidal wheel washer 26 is disposed between the transmission mechanism 25 and the reducer lower housing 27. The upper cycloidal wheel washer 24 and the lower cycloidal wheel washer 26 are made of 304 stainless steel with a thickness of 0.1mm; the reducer upper housing 23 and the reducer lower housing 27 are made of aluminum alloy.

[0063] The upper swing wheel shim 24 and the lower swing wheel shim 26 are used to separate the upper housing 23 or the lower housing 27 of the reducer from the transmission mechanism 25 of the reducer, which helps to reduce transmission failures caused by wear on the surfaces of the upper housing 23 and the lower housing 27 of the reducer during high torque transmission.

[0064] Reference Figure 5 The reducer upper housing 23 is provided with a through hole for fixing to the explosion-proof housing 2 and a threaded hole for fixing external equipment. The output end of the transmission mechanism 25 is connected to an output flange 21, which is connected to the reducer upper housing 23 through an upper crossed roller bearing 22. The double-stitched shaft 9 is fixed to the output flange 21 with screws.

[0065] Reference Figure 5 and Figure 6 The upper housing 23 and the lower housing 27 of the reducer are fixed by fixing screws 28. Furthermore, the upper housing 23 and the lower housing 27 of the reducer are evenly provided with multiple pin holes for assembling pins 47, and pins 46 are sleeved on the pins 47. The upper housing 23 and the lower housing 27 of the reducer form a stable transmission cage structure, which makes the cycloidal reducer 1 have high rigidity.

[0066] Reference Figure 6 The transmission mechanism 25 includes an upper cycloidal wheel 38 and a lower cycloidal wheel 42 with staggered teeth. Both the upper cycloidal wheel 38 and the lower cycloidal wheel 42 mesh with needle teeth 46. The number of teeth on the upper cycloidal wheel 38 and the lower cycloidal wheel 42 is one less than the number of teeth on the needle teeth 46. The needle teeth 46 can rotate on the needle pin 47. The friction between the upper cycloidal wheel 38 and the lower cycloidal wheel 42 and the needle teeth 46 is rolling friction, which can improve the transmission efficiency.

[0067] Reference Figure 5 and Figure 6The input end of the transmission mechanism 25 includes an eccentric assembly for driving the upper cycloidal wheel 38 and the lower cycloidal wheel 42 to rotate. Specifically, the eccentric assembly includes an upper eccentric shaft 37 rotatably disposed on the inner ring of the upper cycloidal wheel 38, and a lower eccentric shaft 44 rotatably disposed on the inner ring of the lower cycloidal wheel 42. The upper eccentric shaft 37 and the lower eccentric shaft 44 are symmetrically arranged at 180° and are fixedly connected by multiple eccentric shaft fixing pins 35. The upper eccentric shaft 37 and the lower eccentric shaft 44 are connected together by an eccentric shaft adapter 29, and the rotor of the brushless motor 4 is connected to the eccentric shaft adapter 29 by screws.

[0068] Reference Figure 5 The outer ring of the eccentric shaft adapter 29 is rotatably connected to an eccentric shaft positioning bearing 31, which provides centering for the upper eccentric shaft 37 and the lower eccentric shaft 44. An output parallel connector 32 is rotatably connected to the outer ring of the eccentric shaft positioning bearing 31. A lower crossed roller bearing 30 is fitted onto the outer ring of the output parallel connector 32, and the outer ring of the lower crossed roller bearing 30 is fitted onto the lower housing 27 of the reducer.

[0069] Reference Figure 6 A ring of upper bearing pins 36 is densely distributed between the outer ring of the upper eccentric shaft 37 and the inner ring of the upper cycloidal wheel 38, and a ring of lower bearing pins 43 is densely distributed between the outer ring of the lower eccentric shaft 44 and the inner ring of the lower cycloidal wheel 42. Both the upper bearing pins 36 and the lower bearing pins 43 are pins with a diameter of 2mm. When the upper eccentric shaft 37 and the lower eccentric shaft 44 rotate, the pins roll in the gap between the outer ring of the eccentric shaft and the corresponding inner ring of the cycloidal wheel, playing a role similar to the rolling elements of a bearing.

[0070] Reference Figure 6 The upper eccentric shaft 37 and the lower eccentric shaft 44 are respectively secured by screws to an upper bearing pin limiting plate 34 and a lower bearing pin limiting plate 45, both of which are made of 1mm thick 304 stainless steel. Furthermore, a flange is provided on one side of the inner ring of both the upper cycloidal wheel 38 and the lower cycloidal wheel 42. The flange of the upper bearing pin limiting plate 34 and the inner ring of the upper cycloidal wheel 38 is used to limit the two ends of the upper bearing pin 36, and the flange of the lower bearing pin limiting plate 45 and the inner ring of the lower cycloidal wheel 42 is used to limit the two ends of the lower bearing pin 43.

[0071] Reference Figure 5 and Figure 6 The output end of the transmission mechanism 25 includes multiple output rollers 40 and output screws 33 passing through the output rollers 40. The output rollers 40 are rotatably disposed in the corresponding through holes of the upper cycloidal wheel 38 and the lower cycloidal wheel 42. An upper limit gasket 39 is provided between the output rollers 40 and the output flange 21, and a lower limit gasket 41 is provided between the output rollers 40 and the output parallel component 32. The upper limit gasket 39 and the lower limit gasket 41 are used to position the output rollers 40 and reduce wear during transmission.

[0072] Reference Figure 6 The output screw 33 passes through the through hole on the output parallel component 32, then sequentially passes through the lower limit washer 41, the output roller 40, and the upper limit washer 39, finally connecting to the output flange 21. The output parallel component 32, the lower crossed roller bearing 30, the output screw 33, the output flange 21, the upper crossed roller bearing 22, the upper reducer housing 23, and the lower reducer housing 27 form a stable transmission cage structure, eliminating the transmission cantilever structure, providing excellent radial force resistance, and possessing good resistance to axial force.

[0073] When the cycloidal reducer 1 is working, the rotor of the brushless motor 4 drives the upper eccentric shaft 37 and the lower eccentric shaft 44 to move eccentrically, so that the upper cycloidal wheel 38 and the lower cycloidal wheel 42 mesh with the needle tooth 46 and push the output roller 40 to move. In this way, after the cycloidal reducer 1 reduces speed and increases torque, the output roller 40 drives the output screw 33 and then drives the output flange 21 to rotate, thus completing the power transmission.

[0074] An eccentric part is a component whose working surface axis is not aligned with the axis of its power input shaft. The precision of the eccentric part (the magnitude of the eccentricity, the precision of 180° symmetry) greatly affects the transmission accuracy and efficiency of the cycloidal reducer. The difficulty in manufacturing a cycloidal reducer lies in the machining of the eccentric part (eccentric shaft). The input eccentricity of industrial cycloidal reducers is mostly generated by eccentric sleeve bearings, but the limited models, large size, and low eccentricity precision of eccentric sleeve bearings restrict the design of small cycloidal reducers.

[0075] This application uses two identical eccentric shafts symmetrically arranged, and uses eccentric shaft fixing pins 35 to ensure the 180° symmetrical assembly relationship of the upper eccentric shaft 37 and the lower eccentric shaft 44 as well as the coaxiality of the two parts, which reduces the difficulty of processing and improves the accuracy of eccentricity.

[0076] The bearings in cycloidal reducers are a major factor limiting their miniaturization. Because cycloidal reducers use an eccentric input method, significant stress is generated at the eccentric shaft. This stress is sufficient to crush ordinary bearings during high-torque transmission. Bearings with sufficient radial load capacity are often large in size (wall thickness, bearing thickness) and have limited allowable speeds. This application uses densely arranged bearing pins and limiting plates to achieve the effect of a bearing, enabling higher speeds under grease lubrication.

[0077] Compared to common industrial cycloidal reducers that use eccentric sleeve bearings, the cycloidal reducer provided in this application has a smaller volume and a thickness as thin as 10mm, making it more suitable for assembling small robot joints.

[0078] This embodiment provides a small-volume, high-rigidity explosion-proof robot joint module that can be used for the assembly of explosion-proof robots.

[0079] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A small-volume, high-rigidity explosion-proof robot joint module, characterized in that: include: Explosion-proof enclosure with an internal cavity; An explosion-proof rear shell is attached to the bottom of the explosion-proof outer shell; A cycloidal reducer is installed on the top of the explosion-proof housing. The stator of the cycloidal reducer, the explosion-proof housing, and the explosion-proof rear housing form the stator of the joint module, and the rotor of the cycloidal reducer serves as the rotor of the joint module. The cavity of the explosion-proof housing is provided with: A brushless motor, wherein the stator of the brushless motor is fixed inside the explosion-proof housing, and the rotor of the brushless motor is connected to the input end of the cycloidal reducer; A motor driver is fixed to the stator of the brushless motor, and the three-phase wires of the brushless motor are connected to the motor driver. An output encoder, installed at the bottom of the motor driver, is used to obtain the position information of the output end of the cycloidal reducer; A motor encoder, mounted on top of the motor driver, is used to obtain the position information of the brushless motor rotor; A double-braided rotating shaft is fixed to the output end of the cycloidal reducer and is used to transmit the position information of the output end of the cycloidal reducer. A cable entry device and a cable exit device are used to enter and exit the explosion-proof enclosure, respectively; An explosion-proof joint structure is provided between the output end of the cycloidal reducer and the stator of the cycloidal reducer, between the double-braided shaft and the output end of the cycloidal reducer, between the cycloidal reducer and the explosion-proof housing, and between the explosion-proof rear housing and the explosion-proof housing for sealing and explosion-proof purposes. The cycloidal reducer includes an upper reducer housing and a lower reducer housing that mesh with each other, and a transmission mechanism disposed between the two. Multiple pin teeth are evenly distributed between the upper and lower reducer housings, and each pin tooth is fitted with pin teeth. The transmission mechanism includes an upper cycloidal wheel and a lower cycloidal wheel with interleaved teeth, both of which mesh with the pin teeth. The input end of the transmission mechanism includes an eccentric assembly for driving the upper and lower cycloidal wheels to rotate. The eccentric assembly includes an upper eccentric shaft rotatably disposed on the inner ring of the upper cycloidal wheel and a lower eccentric shaft rotatably disposed on the inner ring of the lower cycloidal wheel. The upper eccentric shaft and the lower eccentric shaft are symmetrically arranged at 180° and are connected by a plurality of eccentric shaft fixing pins. The upper eccentric shaft and the lower eccentric shaft are connected together by an eccentric shaft adapter. A ring of upper bearing pins is densely distributed between the outer ring of the upper eccentric shaft and the inner ring of the upper cycloidal wheel, and a ring of lower bearing pins is densely distributed between the outer ring of the lower eccentric shaft and the inner ring of the lower cycloidal wheel; the upper eccentric shaft and the lower eccentric shaft are respectively fixedly connected with an upper bearing pin limiting plate and a lower bearing pin limiting plate; the inner rings of the upper cycloidal wheel and the lower cycloidal wheel are each provided with a flange; the upper bearing pin limiting plate and the inner ring flange of the upper cycloidal wheel are used to limit the two ends of the upper bearing pin, and the lower bearing pin limiting plate and the inner ring flange of the lower cycloidal wheel are used to limit the two ends of the lower bearing pin.

2. The explosion-proof robot joint module with small volume and high rigidity according to claim 1, characterized in that: The output end of the transmission mechanism is connected to an output flange, and the double-braided shaft is fixedly connected to the output flange.

3. The explosion-proof robot joint module with small volume and high rigidity according to claim 2, characterized in that: An upper swing wheel washer is provided between the transmission mechanism and the upper housing of the reducer, and a lower swing wheel washer is provided between the transmission mechanism and the lower housing of the reducer.

4. The explosion-proof robot joint module with small volume and high rigidity according to claim 2, characterized in that: The output end of the transmission mechanism includes multiple output rollers and an output screw passing through the output rollers. The output rollers are rotatably disposed in the through holes of the upper and lower cycloidal wheels, and the output screws are fixedly connected to the output flange.

5. A small-volume, high-rigidity explosion-proof robot joint module according to claim 4, characterized in that: The outer ring of the eccentric shaft adapter is rotatably connected to an eccentric shaft positioning bearing, which is used to provide centering for the upper and lower eccentric shafts; the eccentric shaft positioning bearing is rotatably connected to an output parallel connector, which has a through hole for the output screw to pass through.

6. The explosion-proof robot joint module with small volume and high rigidity according to claim 5, characterized in that: An upper limit gasket is provided between the output roller and the output flange, and a lower limit gasket is provided between the output roller and the output parallel component.

7. The explosion-proof robot joint module with small volume and high rigidity according to claim 1, characterized in that: The explosion-proof joint structure is a socket joint structure or a stop joint structure.

8. An explosion-proof robot, characterized in that: Including the explosion-proof robot joint module with small volume and high rigidity as described in any one of claims 1-7.

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