A rotary joint with a fool-proof structure and a robot

Abstract

This utility model discloses a rotary joint with a foolproof structure and a robot. The rotary joint includes a joint housing, the interior of which forms an assembly cavity. A joint motor is interference-fitted into the assembly cavity. A cylindrical hole is provided on the side wall of the joint housing, and a cylindrical pin is disposed in the cylindrical hole, extending upward from the opening of the cylindrical hole. In this utility model, by providing a cylindrical pin and extending it upward from the opening of the cylindrical hole, a foolproof positioning structure can be formed, enabling foolproof positioning during the assembly of the joint motor and the safety brake.

Description

Technical Field

[0001] This utility model belongs to the field of robotics, and in particular relates to a rotary joint with a foolproof structure and a robot. Background Technology

[0002] Robot joints are the core moving parts of a robot, and their design directly determines the robot's flexibility, precision, and load-bearing capacity. Different types of joints are suitable for different scenarios, from industrial robotic arms to the limbs of humanoid robots, and joint structures continue to evolve. Modern robot joints increasingly employ rotary joint structures. However, the following problems still exist in the current production process of rotary joints:

[0003] Firstly, during CNC mass production of robot joint housings, even within reasonable tolerances, the diameter of the manufactured products will still have upper and lower tolerance limits. Furthermore, the interference fit between the joint housing and stator during thermoforming assembly, achieved through thermal expansion and contraction, may not always meet requirements. For example, a customer might require an interference tolerance of 0.04mm for the arm housing and a thrust specification of 1000N (MIN). However, due to subtle differences in processing temperature and testing conditions, the actual thrust output of the rotary joint during stator thrust testing of the first and last products falls between 900N and 1300N, failing to guarantee above 1000N. This results in 5% to 10% of defective thrust products.

[0004] Secondly, during the assembly and use of the robot arm, because the joint housing structure lacks obvious features for coarse positioning and foolproofing, the U, V, and W phase pins of the joint motor are prone to hitting other parts of the joint housing and causing damage when assembling with the safety brake. Utility Model Content

[0005] In view of the shortcomings of the prior art, the technical problem to be solved by this utility model is to provide a rotary joint with a foolproof structure and a robot.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] A rotary joint with a foolproof structure includes a joint housing, an assembly cavity formed inside the joint housing, and a joint motor connected to the assembly cavity by an interference fit; a cylindrical hole is provided on the side wall of the joint housing, and a cylindrical needle is provided in the cylindrical hole, with the cylindrical needle extending upward out of the opening of the cylindrical hole.

[0008] Furthermore, the cylindrical needle is interference-fitted with the cylindrical hole, which is used to increase the clamping force of the joint housing on the joint motor through the extrusion force generated by the interference fit with the cylindrical hole.

[0009] Furthermore, the side wall of the joint housing has an outwardly protruding protrusion structure integrally formed at the position corresponding to the cylindrical hole.

[0010] Furthermore, the axis of the cylindrical hole is parallel to the axis of the joint housing.

[0011] Furthermore, the cylindrical needle includes an extrusion section and a positioning section connected to the upper end of the extrusion section. The extrusion section is cylindrical and is used to create an interference fit with the cylindrical hole. The size of the positioning section is smaller than the size of the extrusion section, and the upper end of the positioning section extends out of the opening of the cylindrical hole.

[0012] Furthermore, the cylindrical needle also includes a guide section connected to the lower end of the extrusion section, the guide section being tapered at the top and tapered at the bottom.

[0013] Furthermore, the angle between the side of the guide section and the axial direction is 1° to 5°, and the cylindrical needle is embedded in the cylindrical hole by riveting.

[0014] Furthermore, the joint motor includes a rotating shaft, a rotor, and a stator disposed in the assembly cavity. The stator is interference-fitted into the joint housing. The stator is annular. The rotor is sleeved on the rotating shaft and disposed within the annular hollow of the stator.

[0015] Furthermore, the rotating shaft includes a first cylindrical segment and a second cylindrical segment, the diameter of the first cylindrical segment being larger than the diameter of the second cylindrical segment; a baffle is provided in the assembly cavity, thereby dividing the assembly cavity into a first cavity with an upward opening and a second cavity with a downward opening, the first cylindrical segments of the stator, rotor, and rotating shaft are all disposed in the first cavity, and one end of the first cylindrical segment extends upward beyond the upper opening of the first cavity; a first through hole is provided in the middle of the baffle, the diameter of the first through hole being adapted to the diameter of the second cylindrical segment; the second cylindrical segment passes downward through the first through hole and extends into the second cavity.

[0016] A robot comprising a rotary joint with a foolproof structure as described in any of the preceding claims.

[0017] In this invention, a cylindrical hole is provided on the side wall of the joint housing, and a cylindrical pin is placed in the cylindrical hole, extending upwards from the opening of the cylindrical hole. This cylindrical pin forms a second positioning structure during assembly with the safety brake, thus creating a foolproof positioning structure. When assembling the safety brake on the rotating joint, the three conductive pins and the three spring clips on the safety brake can be accurately connected, preventing damage to the conductive pins. The cylindrical pin uses an interference fit connection, and the compressive force generated by the interference fit between the cylindrical pin and the cylindrical hole causes a slight deformation of the joint housing, thereby increasing the clamping force of the joint housing on the joint motor and improving the product assembly pressure. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0019] Figure 1 This is a schematic diagram of an embodiment of a rotary joint with a foolproof structure according to the present invention.

[0020] Figure 2 for Figure 1 Exploded view.

[0021] Figure 3 for Figure 1 Top view.

[0022] Figure 4 for Figure 3 A schematic diagram of the AA-direction cross section.

[0023] Figure 5 This is a schematic diagram of the joint shell structure.

[0024] Figure 6 This is a schematic diagram of the safety brake.

[0025] Figure 7 This is a schematic diagram of the cylindrical needle.

[0026] The diagrams in the instruction manual are labeled as follows:

[0027] Joint housing - 100; Assembly cavity - 110; First cavity - 111; Second cavity - 112; Baffle - 120; First through hole - 121; Second through hole - 122; Protruding structure - 130; Cylindrical hole - 140; Gap - 141; Connecting hole - 150; Cylindrical pin - 160; Extrusion section - 161; Guide section - 162; Positioning section - 163;

[0028] Shaft-200; First cylindrical section-210; Second cylindrical section-220; Rotor-300; Permanent magnet-310; Stator-400; Conductive pin-410; Stator circuit board-500; Third through hole-510; Turbofan blade-600; Bearing-700; Safety brake-900; Fourth through hole-901; Fifth through hole-902. Detailed Implementation

[0029] The following specific examples illustrate the implementation of this utility model. The illustrations provided in the following embodiments are only schematic representations of the basic concept of this utility model. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0030] Please see Figure 1 , Figure 1This is a schematic diagram of an embodiment of a rotary joint with a foolproof structure according to the present invention. The rotary joint with a foolproof structure in this embodiment includes a joint housing 100, which is generally cylindrical. An assembly cavity 110 is formed inside the joint housing 100, and a joint motor is interference-fitted into the assembly cavity 110. A cylindrical hole 140 is provided on the side wall of the joint housing 100. To avoid affecting the structural strength of the joint housing 100 after the cylindrical hole 140 is provided, an outwardly protruding protrusion 130 is provided on the side wall of the joint housing 100 corresponding to the position of the cylindrical hole 140. The protrusion 130 is integrally formed with the joint housing 100. The axis of the cylindrical hole 140 is parallel to the axis of the joint housing 100, i.e., parallel to... Figure 1 The z-axis direction is parallel.

[0031] A cylindrical needle 160 is provided in the cylindrical hole 140. The cylindrical needle 160 extends upward out of the opening of the cylindrical hole 140, so that the part of the cylindrical needle 160 extending out of the cylindrical hole 140 forms a positioning structure, thereby obtaining a foolproof positioning structure when connecting the safety brake 900.

[0032] In this embodiment, the cylindrical pin 160 is connected to the cylindrical hole 140 by an interference fit. The compression force generated by the interference fit with the cylindrical hole 140 can fix the cylindrical pin 160 in the cylindrical hole 140, and can cause a slight deformation of the joint housing 100, thereby increasing the clamping force of the joint housing 100 on the joint motor. Of course, multiple protrusions 130, cylindrical holes 140 and cylindrical pins 160 can be provided, and the specific number can be determined according to the actual situation.

[0033] Please see Figure 2 , Figure 3 and Figure 4 The joint motor generally includes a rotating shaft 200, a rotor 300, and a stator 400 disposed within an assembly cavity 110. The stator 400 is interference-fitted into the joint housing 100 and is annular in shape. The rotor 300 is sleeved on the rotating shaft 200 and disposed within the annular hollow of the stator 400. Of course, the stator 400 contains stator windings (not shown in the figure), and the rotor 300 contains permanent magnets 310, thereby forming electromagnetic coupling between the stator 400 and the rotor 300. The joint motor also includes a stator circuit board 500, to which the stator windings are electrically connected. These are standard configurations and will not be elaborated upon here.

[0034] Please see Figure 3 , Figure 4 and Figure 5In this embodiment, the rotating shaft 200 includes a first cylindrical segment 210 and a second cylindrical segment 220, wherein the diameter of the first cylindrical segment 210 is larger than the diameter of the second cylindrical segment 220. A baffle 120 is provided in the assembly cavity 110, thereby dividing the assembly cavity 110 into a first cavity 111 with an upward opening and a second cavity 112 with a downward opening. The first cylindrical segments 210 of the stator 400, rotor 300, and rotating shaft 200 are all disposed in the first cavity 111, and one end of the first cylindrical segment 210 extends upward beyond the upper opening of the first cavity 111. A first through hole 121 is provided in the middle of the baffle 120, and the diameter of the first through hole 121 is adapted to the diameter of the second cylindrical segment 220. The second cylindrical segment 220 passes downward through the first through hole 121 and extends into the second cavity 112.

[0035] Please see Figure 6 The joint motor is generally also connected to a safety brake 900. The upper end of the stator 400 is generally provided with three conductive pins 410, serving as U, V, and W phase pins respectively, for connecting with three spring contacts on the safety brake 900 to achieve a U, V, and W phase electrical connection between the stator 400 and the safety brake 900. However, in the existing structure, when the joint motor is connected to the safety brake 900, only the first cylindrical section 210 and the fourth through hole 901 in the middle of the safety brake 900 are used for positioning. This results in the three conductive pins 410 and the three spring contacts (not shown in the figure) on the safety brake 900 not being accurately positioned during connection. When the connection is misaligned, the three conductive pins 410 are easily bent or broken due to collisions with other parts of the safety brake 900.

[0036] Please see Figure 7Since the safety brake 900 generally has multiple through holes (i.e., the fifth through hole 902) at the end facing the joint housing 100, the cylindrical hole 140 can be set at a position corresponding to the fifth through hole 902 on the safety brake 900 in order to utilize the existing fifth through hole 902 on the safety brake 900 for positioning. The cylindrical needle 160 may include a pressing section 161 and a positioning section 163 connected to the upper end of the pressing section 161. The pressing section 161 is cylindrical and is used to create an interference fit with the cylindrical hole 140; the positioning section 163 extends upward out of the opening of the cylindrical hole 140. The size of the positioning section 163 is smaller than the size of the pressing section 161, and the shape of the positioning section 163 is adapted to the shape of the fifth through hole 902 on the safety brake 900. When the joint motor is connected to the safety brake 900, the positioning section 163 extends into the corresponding fifth through hole 902. Together with the first cylindrical section 210 and the fourth through hole 901, two pairs of positioning structures can be formed, thus forming a foolproof positioning structure when connecting the safety brake 900. This ensures that the three conductive pins 410 and the three spring pieces on the safety brake 900 are accurately connected, preventing damage to the conductive pins 410 during the connection process.

[0037] Please continue reading. Figure 6 To facilitate the installation of the cylindrical needle 160 into the cylindrical hole 140, the cylindrical needle 160 may further include a guide section 162 connected to the lower end of the extrusion section 161. The guide section 162 is tapered at the top and tapered at the bottom to facilitate guidance during the installation of the cylindrical needle 160. The side of the guide section 162 is aligned with the axial direction (i.e.,...). Figure 1 The included angle (in the z-axis direction) can be 1° to 5°, which facilitates the insertion of the cylindrical needle 160 into the cylindrical hole 140 by riveting. For example, the included angle can be 1°, 1.5°, 2°, 2.5°, 3°, 3.5°, 4°, 4.5°, or 5°; in this embodiment, the included angle is preferably 1.2°.

[0038] Please continue reading. Figure 3 and Figure 4 To facilitate heat dissipation of the joint motor, the baffle 120 has multiple second through holes 122 on the outer side of the first through hole 121, connecting the first cavity 111 and the second cavity 112. A bearing 700 and a turbofan blade 600 are disposed in the second cavity 112, and the second cylindrical segment 220 is fixedly inserted into the middle of the turbofan blade 600. The outer side of the turbofan blade 600 is fixedly connected to the inner ring of the bearing 700, and the outer ring of the bearing 700 is fixedly connected to the cavity wall at the lower opening of the second cavity 112. In this embodiment, the stator circuit board 500 is disposed in the second cavity 112, located between the turbofan blade 600 and the baffle 120, and the stator circuit board 500 has multiple third through holes 510 to form a heat dissipation channel in the second cavity 112.

[0039] To facilitate air convection during heat dissipation, the joint housing 100 is also provided with a connecting hole 150 that connects the bottom of the cylindrical hole 140 and the assembly cavity 110; in this embodiment, the connecting hole 150 is preferably connected to the upper part of the second cavity 112. Furthermore, the cylindrical pin 160 abuts against and is interference-fitted with the cylindrical hole 140 in the radial direction of the joint housing 100. A gap 141 is formed between the sidewalls of the cylindrical pin 160 on both radial sides of the joint housing 100 and the hole wall of the cylindrical hole 140, thereby creating another air duct connecting the assembly cavity 110 to the outside through the gaps 141 on both sides of the cylindrical pin 160 and the connecting hole 150. When the rotating shaft 200 drives the turbine blades 600 to rotate, the air in the assembly cavity 110 will be quickly discharged through the lower opening of the second cavity 112; at the same time, air will be supplied to the assembly cavity 110 through the air duct formed by the gap 141 and the connecting hole 150, forming convection, thereby quickly dissipating the heat generated in the assembly cavity 110 when the joint motor is working through air flow, thus solving the problem of trapped air and heat dissipation in the assembly cavity 110, so that the joint motor can obtain stable output power when working for a long time.

[0040] In this embodiment, by providing a cylindrical hole 140 on the side wall of the joint housing 100 and selecting the opening position of the cylindrical hole 140 so that the cylindrical pin 160 extends outside the cylindrical hole 140, the cylindrical pin 160 can form a second positioning structure when assembling with the safety brake 900. This allows for accurate positioning when assembling the safety brake 900 on the rotary joint, ensuring accurate connection between the three conductive pins 410 and the three spring pieces on the safety brake 900, and preventing damage to the conductive pins 410. The cylindrical pin 160 is connected by an interference fit in the cylindrical hole 140. The compressive force generated by the interference fit between the cylindrical pin 160 and the cylindrical hole 140 causes a slight deformation of the joint housing 100, thereby increasing the clamping force of the joint housing 100 on the joint motor and improving the product assembly pressure. For example, when the interference tolerance between the joint housing 100 and the stator 300 is approximately 0.04 mm, in this embodiment, by adding the cylindrical hole 140 and the cylindrical pin 160, the thrust range output by the rotary joint can be improved from 900 N to 1300 N to a stable value above 1000 N. Thus, the cylindrical pin 160 and the cylindrical hole 140 can simultaneously achieve two functions: improving the assembly pressure of the stator 400 and providing foolproof positioning during the assembly of the safety brake 900.

[0041] Furthermore, by providing a connecting hole 150 between the cylindrical hole 140 and the assembly cavity 110, and leaving a gap 141 between the cylindrical pin 160 and the hole wall of the cylindrical hole 140, an air convection duct can be formed in the assembly cavity 110. Then, by providing a turbofan blade 600 at the lower opening of the second cavity 112, stable air convection can be formed in the assembly cavity 110 through the rotation of the turbofan blade 600, avoiding the formation of trapped air in localized areas within the assembly cavity 110. This airflow-guided heat dissipation improves the stability of the joint motor. In other words, the specific structure of the cylindrical hole 140 allows the cylindrical pin 160 and the cylindrical hole 140 to simultaneously serve a third function.

[0042] This utility model also discloses a robot, which includes a rotary joint with a foolproof structure as described in any of the above embodiments. For example, the rotary joint can be used as the robot's arm joint, which facilitates the assembly of a safety brake 900 on the arm joint, and also enables the robot's arm joint to have a high actual thrust and keep the thrust stable.

[0043] The above embodiments only illustrate preferred implementations of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A rotary joint with a foolproof structure, characterized in that: The device includes a joint housing, the interior of which is formed an assembly cavity, in which a joint motor is interference-fitted; a cylindrical hole is provided on the side wall of the joint housing, and a cylindrical needle is provided in the cylindrical hole, with the cylindrical needle extending upward out of the opening of the cylindrical hole.

2. A rotary joint with a foolproof structure as described in claim 1, characterized in that: The cylindrical needle is interference-fitted with the cylindrical hole, which is used to increase the clamping force of the joint housing on the joint motor through the extrusion force generated by the interference fit with the cylindrical hole.

3. A rotary joint with a foolproof structure as described in claim 1, characterized in that: The joint housing has an integrally formed outward protrusion structure at the position corresponding to the cylindrical hole on its side wall.

4. A rotary joint with a foolproof structure as described in claim 1, characterized in that: The axis of the cylindrical hole is parallel to the axis of the joint housing.

5. A rotary joint with a foolproof structure as described in claim 1, characterized in that: The cylindrical needle includes a pressing section and a positioning section connected to the upper end of the pressing section. The pressing section is cylindrical and is used to create an interference fit with the cylindrical hole. The size of the positioning section is smaller than that of the pressing section, and the upper end of the positioning section extends out of the opening of the cylindrical hole.

6. A rotary joint with a foolproof structure as described in claim 1, characterized in that: The cylindrical needle also includes a guide section connected to the lower end of the extrusion section, the guide section being tapered at the top and tapered at the bottom.

7. A rotary joint with a foolproof structure as described in claim 6, characterized in that: The angle between the side of the guide section and the axial direction is 1° to 5°, and the cylindrical needle is embedded in the cylindrical hole by riveting.

8. A rotary joint with a foolproof structure as described in any one of claims 1 to 7, characterized in that: The joint motor includes a rotating shaft, a rotor, and a stator disposed in the assembly cavity. The stator is interference-fitted into the joint housing. The stator is annular. The rotor is sleeved on the rotating shaft and disposed in the annular hollow of the stator.

9. A rotary joint with a foolproof structure as described in claim 8, characterized in that: The rotating shaft includes a first cylindrical segment and a second cylindrical segment, the diameter of the first cylindrical segment being larger than the diameter of the second cylindrical segment; a baffle is provided in the assembly cavity, thereby dividing the assembly cavity into a first cavity with an upward opening and a second cavity with a downward opening; the first cylindrical segments of the stator, rotor, and rotating shaft are all disposed in the first cavity, and one end of the first cylindrical segment extends upward beyond the upper opening of the first cavity; a first through hole is provided in the middle of the baffle, the diameter of the first through hole being adapted to the diameter of the second cylindrical segment; the second cylindrical segment passes downward through the first through hole and extends into the second cavity.

10. A robot, characterized in that: Including a rotary joint with a foolproof structure as described in any one of claims 1 to 9.

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