A robot joint brake assembly with a tensioning mechanism

Abstract

The utility model relates to the field of robot technology, and in particular to a robot joint brake assembly with a tensioning mechanism, which is arranged in the robot joint, and also includes a motor assembly, a harmonic reducer and a shaft group, and the brake assembly is arranged between the motor assembly and the harmonic reducer; the brake body fixing piece is sleeved and fixed on the input shaft, the brake body is connected to the lower end surface of the brake body fixing piece flange and forms a brake surface with the upper end surface of the brake pad, the brake pad is arranged on the brake pad mounting piece, and a tensioning structure for maintaining the distance between the brake pad and the brake body is arranged between the brake pad and the brake pad mounting piece. The robot joint module described in the utility model adopts a friction brake assembly, and the brake pad will automatically hold the brake body for braking when the power is off, so the safety and reliability are greatly increased.

Description

Technical Field

[0001] The utility model relates to the technical field of robots, in particular to a robot joint braking component with a tensioning mechanism. Background Art

[0002] With the rapid development of automation technology, robots, as an important automation equipment, are gaining more and more attention and are being used more and more widely. As an important branch of robots, medical robots are developing rapidly. More and more medical robots are being developed and put into the market after rigorous testing, becoming a powerful assistant for frontline medical staff and patients.

[0003] Due to the particularity of medical application scenarios, there are many stringent requirements for the safety and reliability of medical robots. The core component that determines the motion performance of medical robots is the joint module. Therefore, the operating accuracy and reliability of the joint module of medical robots are required to be high. Among them, the brake component of the robot shutdown is an important factor in evaluating the reliability of the robot joint. The robot joint module of the related technology does not have sufficient safety measures. When the hospital suddenly loses power, the brake component cannot lock the movement of the robot arm, causing the robot arm to fall or be out of control, thus putting doctors and patients in an unsafe situation. Utility Model Content

[0004] In view of this, the utility model provides a robot joint brake assembly with a tensioning mechanism, which at least partially solves the problems existing in the prior art.

[0005] A robot joint brake assembly with a tensioning mechanism, which is arranged in a robot joint, wherein the robot joint further comprises a motor assembly, a harmonic reducer and a shaft group, and the brake assembly is arranged between the motor assembly and the harmonic reducer;

[0006] The motor assembly includes a housing, a rotor, and a stator, wherein the stator is arranged on the inner wall of the housing; the shaft group includes a coaxially arranged input shaft and an output shaft, and the brake assembly includes a brake pad, a brake body fixing part, a brake body, a brake pad mounting part, and a tensioning structure;

[0007] The brake body fixing piece is sleeved and fixed on the input shaft, the brake body is connected to the lower end surface of the brake body fixing piece flange and constitutes a braking surface with the upper end surface of the brake pad, the brake pad is arranged on the brake pad mounting piece, and a tensioning structure for maintaining the distance between the brake pad and the brake body is arranged between the brake pad and the brake pad mounting piece.

[0008] Preferably, the tensioning structure includes bolts passing through the brake pad and the brake pad mounting member and an elastic member arranged on the brake pad.

[0009] Preferably, the elastic member is a coil spring inserted through the bolt, or the elastic member is a spring sheet arranged between the brake pad and the end of the bolt.

[0010] Preferably, the brake body fixing part is a hollow stepped shaft structure with a flange, which is sleeved and fixed on the input shaft, and the rotor is fixedly connected to the stepped shaft of the brake body fixing part and forms a motor with the stator.

[0011] Preferably, the brake pad mounting piece is an annular flange structure, and the outer edge of the brake pad mounting piece extends to the outer surface of the shell along the diameter direction and is fixedly connected to the lower end of the shell.

[0012] Preferably, the brake body annular structure has an annular groove on its lower end surface.

[0013] Preferably, the shaft assembly further includes a second input bearing, and a second bearing mounting position for mounting the second input bearing is provided on the brake pad mounting member, and an inner ring of the second input bearing is fixedly mounted on the lower portion of the input shaft.

[0014] Preferably, the brake pad mounting piece and the housing are an integral metal structure.

[0015] Preferably, a positioning shoulder is provided at the middle of the input shaft, and the lower end surface of the brake body fixing part abuts against the positioning shoulder.

[0016] Preferably, heat-conducting glue is provided between the brake pad mounting piece and the housing.

[0017] The robot joint brake assembly with a tensioning mechanism described in the utility model adopts a friction brake assembly, and the brake pads will automatically hold the brake body to brake when the power is off, so the safety and reliability are greatly improved;

[0018] In addition, because the brake assembly is arranged between the motor assembly and the harmonic reducer, that is, in the middle of the input shaft, the input shaft is subjected to more balanced force and smaller shaft vibration during braking, and the braking stability is good. Moreover, because a tensioning structure is arranged between the brake pad and the brake body fixing part, the distance between the brake pad and the brake body can be kept unchanged. Even if the brake pad is worn, the gap between the brake pad and the brake body can still be guaranteed to remain unchanged. Therefore, there is no need for subsequent maintenance. The braking torque can always be maintained unchanged during the life cycle of the brake pad. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a three-dimensional schematic diagram of a robot joint to which the braking assembly described in the embodiment of the utility model is applied;

[0021] Figure 2 A schematic front view of a robot joint to which the brake assembly according to an embodiment of the utility model is applied;

[0022] Figure 3 for Figure 2 Schematic cross-sectional view of the AA plane;

[0023] Figure 4 for Figure 3 A partial enlarged view of the middle tension structure;

[0024] Figure 5 It is a schematic diagram of an exploded view of the joint structure of a robot to which the braking assembly described in the embodiment of the utility model is applied.

[0025] Description of reference numerals:

[0026] 11-housing, 12-rotor, 13-stator;

[0027] 21-brake body fixing part, 22-brake pad, 23-brake body, 24-tensioning structure, 241-bolt, 242-elastic part, 25-brake pad mounting part;

[0028] 31-flexible wheel, 32-steel wheel, 33-reducer bearing, 34-wave generator;

[0029] 41-input shaft, 411-positioning shoulder, 412-first thread, 42-input locking nut, 43-first input bearing, 44-second input bearing, 45-output shaft, 451-second thread, 46-output locking nut, 47-first output bearing. DETAILED DESCRIPTION

[0030] The embodiments of the utility model are described in detail below with reference to the accompanying drawings.

[0031] It should be noted that the following embodiments and features in the embodiments may be combined with each other in the absence of conflict; and, based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making any creative work are within the scope of protection of the present disclosure.

[0032] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein may be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein may be implemented independently of any other aspect, and two or more of these aspects may be combined in various ways. For example, any number of aspects described herein may be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein may be used to implement this device and / or practice this method.

[0033] Figures 1 to 5 The present embodiment will now be described in detail in conjunction with the accompanying drawings, which include a three-dimensional schematic diagram, a front view, a cross-sectional schematic diagram, a partial enlarged diagram, and a partial exploded diagram of a robot joint to which the braking assembly described in the embodiment of the utility model is applied.

[0034] See also Figures 1 to 5 As shown, the robot joint module described in this embodiment includes a motor assembly, a friction brake assembly, a harmonic reducer and a shaft group that runs through the motor assembly, the friction brake assembly and the harmonic reducer, which are arranged from top to bottom, wherein: the motor assembly includes a housing 11, a rotor 12, and a stator 13; the brake assembly includes a brake pad 22, a brake body fixing member 21, a brake body 23, a brake pad mounting member 25 and a tensioning structure 24; the harmonic reducer includes a flexible wheel 31, a steel wheel 32, a reducer bearing 33, and a wave generator 34; the shaft group includes a coaxially arranged input shaft 41 and an output shaft 45, and also includes an input locking nut 42, a first input bearing 43, a second input bearing 44, an output locking nut 46 and a first output bearing 47;

[0035] Among them, the stator 13 is provided with a winding coil, the rotor 12 is a permanent magnet, the output shaft 45 is a hollow shaft, the input shaft 41 is sleeved on the output shaft 45, the shell 11 is a cylindrical metal structure, and the stator 13 is arranged on the inner wall of the shell 11; the stator 13 is sleeved on the brake body fixing part 21, the brake body fixing part 21 and the brake body 23 are both sleeved on the middle part of the input shaft 41, the brake body fixing part 21 is fixed on the input shaft 41, the brake body 23 is connected to the lower end surface of the flange of the brake body fixing part 21 and constitutes a braking surface with the upper end surface of the brake pad 22), the brake pad 22 is arranged on the brake pad mounting part 25, the outer edge of the brake pad mounting part 25 extends to the outer surface of the shell 11 along the diameter direction and is fixedly connected to the lower end of the shell 11, and a tensioning structure 24 for maintaining the distance between the brake pad 22 and the brake body 23 is arranged between the brake pad 22 and the brake pad mounting part 25.

[0036] The above-mentioned robot joint module adopts a friction brake assembly, so the brake pad 22 will automatically hold the brake body 23 for braking when the power is off, thereby greatly increasing safety and reliability; in addition, because the brake assembly is arranged in the middle of the input shaft 41, during braking, the input shaft 41 is subjected to a more balanced force, the shaft jump is smaller, and the braking stability is good. Moreover, because the brake pad mounting part 25 extends to the outer surface of the shell 11 along the diameter direction, it not only has a larger volume and a higher heat capacity, but also has a fast heat dissipation, which greatly improves the adaptability of the robot joint module and improves reliability.

[0037] Reference Figure 1-5 It can be seen that in the brake assembly described in this embodiment, the brake body 23 is an annular structure, which forms a clearance fit with the input shaft 41; the brake body fixing part 21 is a hollow stepped shaft structure with a flange, which is sleeved and fixed on the input shaft 41, and the rotor 12 is fixedly connected to the stepped shaft of the brake body fixing part 21, and forms a motor with the stator 13; the brake pad 22 is arranged on the brake pad mounting part 25, and forms a braking surface with the lower end face of the brake body 23, and a tensioning structure 24 for maintaining the distance between the brake pad 22 and the brake body 23 is provided between the brake pad 22 and the brake pad mounting part 25.

[0038] The tensioning structure 24 includes a bolt 241 passing through the brake pad 22 and the brake pad mounting member 25 and an elastic member 242 arranged on the brake pad 22. In the present embodiment, the elastic member 242 is a coil spring passing through the bolt 241. In other embodiments, the elastic member 242 may be a spring arranged between the brake pad 22 and the end of the bolt 24.

[0039] From the above, it can be seen that because a tensioning structure 24 is provided between the brake pad 22 and the brake body fixing part 21, the distance between the brake pad 22 and the brake pad mounting part 25 can be kept unchanged, thereby keeping the gap between the brake pad 22 and the brake body 23 unchanged. Even if the brake pad 22 is worn, the gap between the brake pad 22 and the brake body 23 can still be guaranteed to remain unchanged. Therefore, there is no need for subsequent maintenance, and the braking torque can always be maintained unchanged during the life cycle of the brake pad 22.

[0040] Reference Figure 3 and Figure 5 It can be seen that an annular groove is provided on the lower end surface of the brake body 23, and the annular groove is composed of two annular convex ribs extending downward. This structure not only reduces the weight of the brake body 23, but also increases the heat dissipation surface, so that the heat generated by friction braking can be dissipated faster; in addition, this annular groove structure changes the braking surface between the brake body 23 and the brake pad 22 from surface contact to line contact. Even if the brake body 23 and the brake pad 22 are deformed by heat, the effective contact of the braking surface can still be guaranteed, thereby ensuring the reliability of braking.

[0041] Reference Figure 3 and Figure 5 It can be seen that a second bearing mounting position 231 for mounting a second input bearing 44 is provided on the brake pad mounting member 25, and the inner ring of the second input bearing 44 is fixedly mounted on the input shaft 41. The second input bearing 44 is located in the lower middle part of the input shaft 41, and cooperates with the first input bearing 43 located at the top end of the input locking nut 42 to form a double bearing support for the input shaft 41; because the braking surface of the brake assembly and the rotor 12 of the motor assembly are both arranged between the double bearings of the input shaft 41, the double bearing structure of the input shaft 41 can greatly improve the stability of motor driving and braking, prevent the input shaft 41 from jumping or shaking, and greatly reduce the vibration of the input shaft 41.

[0042] Reference Figure 3 and Figure 5 It can be seen that a positioning shoulder 441 is provided in the middle of the input shaft 41, and the brake body fixing part 21 is sleeved on the input shaft 41 and the lower end face abuts against the positioning shoulder 441. The upper end of the input shaft 41 is provided with a first thread 412 matching the input locking nut 42, and the input locking nut 42 is connected to the upper end of the input shaft 41 through the first thread 412, and the lower end of the locking nut abuts against the upper end of the brake body fixing part 21. It can be seen from the above structure that as long as the position accuracy of the positioning shoulder 441 on the input shaft 41, the length accuracy of the brake body fixing part 21 and the height accuracy of the input locking nut 42 are ensured, the height accuracy of the top surface of the input locking nut 42 relative to the bottom surface of the wave generator 34 can be ensured.

[0043] An annular boss is provided at the upper end of the input locking nut 42, and an outer edge bearing mounting position and an inner edge bearing mounting position are respectively provided on the outer edge and inner edge of the annular boss. The inner ring of the first input bearing 43 is installed in the outer edge bearing mounting position, and the outer ring of the first input bearing 43 cooperates with the inner wall of the upper end of the shell 11. Therefore, as long as the assembly accuracy of the outer ring of the first input bearing 43 on the inner wall of the upper end of the shell 11 can be ensured, the assembly accuracy of the input shaft 41 in the vertical direction can be ensured, thereby ensuring that the wave generator 34 is installed in a suitable position.

[0044] Reference Figure 1-3It can be seen that the outer surface of the shell 11 is provided with convex rib-shaped heat dissipation ribs, and the stator 13 is arranged on the inner wall of the shell 11. Therefore, the heat generated by the stator 13 during operation can be quickly dissipated through the heat dissipation ribs of the shell 11, and heat accumulation will not be generated in the joints, which greatly improves the working environment of the motor assembly and the brake assembly. In addition, the heat dissipation ribs of the shell 11 can also play the role of reinforcing ribs. Under the premise of ensuring the strength of the shell 11, the weight of the shell 11 is reduced, which not only reduces the material cost of the shell 11, but also reduces the inertia of the joint when it moves with the robot arm, and reduces the control difficulty of the robot arm. In other embodiments, the heat dissipation ribs on the outer surface of the shell 11 can also be grille-shaped. In some other embodiments, the shell 11 and the brake pad mounting member 25 are an integrated metal structure.

[0045] Reference Figure 3 It can be seen that the lower end of the output shaft 45 is a flange-shaped structure, and forms a harmonic reducer with the flexible wheel 31, the steel wheel 32, and the reducer bearing 33. The upper end surface of the output shaft 45 flange is fixedly connected to the steel wheel 32 and the inner ring of the reducer bearing 33, and a second thread 451 for connecting with the output locking nut 46 is provided at the upper end of the output shaft 45. Moreover, the outer edge of the flexible wheel 31 extends to the outer surface of the housing 11 along the diameter direction and is fixedly connected to the housing 11, the brake pad mounting member 25, and the outer ring of the reducer bearing 33. Heat conductive glue is provided between the brake pad mounting member 25 and the housing 11, and between the brake body 23 and the flexible wheel 31.

[0046] Through the above structure, the heat generated by the harmonic reducer during operation can be transferred to the outer surface of the robot joint through the flexible wheel 31 on the one hand, and dissipated through the steel wheel 32 and the reducer bearing 33 on the other hand, and can also be dissipated through the flange-like structure at the lower end of the output shaft 45.

[0047] In summary, although the embodiment of the utility model adopts a friction brake assembly that is very easy to generate a lot of heat and the brake assembly is arranged between the motor assembly and the harmonic reducer, because heat dissipation ribs are arranged on the outer surface of the shell 11, the heat generated by the stator 13 can be quickly dissipated, and the outer edge of the brake pad mounting part 25 of the brake assembly extends all the way to the outer edge of the shell 11. It has a high heat capacity and can also quickly dissipate the heat of the brake assembly. Coupled with the three-way heat dissipation route of the harmonic reducer, the heat dissipation capacity of the robot joint described in this embodiment is extremely excellent. Therefore, it can have the high safety and high reliability of the friction brake assembly, and will not cause the accumulation of heat inside the robot joint to deteriorate the working environment of the joint.

[0048] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A robot joint brake assembly with a tensioning mechanism, arranged in a robot joint, characterized in that: The robot joint further comprises a motor assembly, a harmonic reducer and a shaft group, and the brake assembly is arranged between the motor assembly and the harmonic reducer; The motor assembly comprises a housing (11), a rotor (12), and a stator (13), wherein the stator (13) is arranged on the inner wall of the housing (11); the shaft assembly comprises an input shaft (41) and an output shaft (45) which are coaxially arranged; and the brake assembly comprises a brake pad (22), a brake body fixing member (21), a brake body (23), a brake pad mounting member (25), and a tensioning structure (24); The brake body fixing member (21) is sleeved and fixed on the input shaft (41), the brake body (23) is connected to the lower end surface of the flange of the brake body fixing member (21) and forms a braking surface with the upper end surface of the brake pad (22), the brake pad (22) is arranged on the brake pad mounting member (25), and a tensioning structure (24) for maintaining the distance between the brake pad (22) and the brake body (23) is arranged between the brake pad (22) and the brake pad mounting member (25).

2. The robot joint brake assembly with a tensioning mechanism according to claim 1, characterized in that: The tensioning structure (24) comprises a bolt (241) passing through the brake pad (22) and the brake pad mounting member (25), and an elastic member (242) arranged on the brake pad (22).

3. The robot joint brake assembly with a tensioning mechanism according to claim 2, characterized in that: The elastic member (242) is a coil spring inserted into the bolt (241), or the elastic member (242) is a spring sheet arranged between the brake pad (22) and the end of the bolt (241).

4. The robot joint brake assembly with a tensioning mechanism according to claim 1, characterized in that: The brake body fixing part (21) is a hollow stepped shaft structure with a flange, which is sleeved and fixed on the input shaft (41). The rotor (12) is fixedly connected to the stepped shaft of the brake body fixing part (21) and forms a motor with the stator (13).

5. The robot joint brake assembly with a tensioning mechanism according to claim 1, characterized in that: The brake pad mounting member (25) is an annular flange structure, and the outer edge of the brake pad mounting member (25) extends to the outer surface of the housing (11) along the diameter direction and is fixedly connected to the lower end of the housing (11).

6. The robot joint brake assembly with a tensioning mechanism according to claim 1, characterized in that: The brake body (23) is an annular structure, and an annular groove is arranged on the lower end surface thereof.

7. The robot joint brake assembly with a tensioning mechanism according to claim 5 or 6, characterized in that: The shaft assembly also includes a second input bearing (44), and a second bearing mounting position for mounting the second input bearing (44) is provided on the brake pad mounting member (25), and the inner ring of the second input bearing (44) is fixedly mounted on the lower part of the input shaft.

8. The robot joint brake assembly with a tensioning mechanism according to claim 1, characterized in that: The brake pad mounting member (25) and the housing (11) are an integrated metal structure.

9. The robot joint brake assembly with a tensioning mechanism according to claim 1, characterized in that: A positioning shoulder (441) is provided in the middle of the input shaft (41), and the lower end surface of the brake body fixing member (21) abuts against the positioning shoulder (441).

10. The robot joint brake assembly with a tensioning mechanism according to claim 9, characterized in that: Heat-conducting glue is provided between the brake pad mounting piece (25) and the housing (11).

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