Brake and motor

Abstract

The present application provides a brake and a motor. The brake includes a rotating hub (1) and a rotor core (2). An annular protrusion (3) is provided at one end of the rotating hub (1) facing the rotor core (2). A keyway (4) is provided on the inner peripheral wall of the annular protrusion (3). A groove (5) is provided at one end of the rotor core (2) facing the rotating hub (1). The annular protrusion (3) is installed in the groove (5). According to the brake of the present application, the size of the brake can be reduced and the power density of the motor can be increased.

Description

Technical Field

[0001] This application relates to the technical field of motors, and particularly to a brake and a motor. Background Art

[0002] With the development of the miniaturization of robots, the market has higher and higher requirements for the miniaturization of motors. Major motor manufacturers are all striving to miniaturize their own products and strive to maximize the motor power density. The brake is an important component of the motor. Therefore, how to reduce the size of the brake and thus increase the motor power density is a problem that the entire robot industry is striving to solve. Summary of the Invention

[0003] Therefore, the technical problem to be solved by this application is to provide a brake and a motor that can reduce the size of the brake and increase the motor power density.

[0004] To solve the above problems, this application provides a brake, including a rotating hub and a mover core. One end of the rotating hub facing the mover core is provided with an annular protrusion. A keyway is provided on the inner peripheral wall of the annular protrusion. One end of the mover core facing the rotating hub is provided with a groove, and the annular protrusion is installed in the groove.

[0005] Preferably, the outer diameter of the annular protrusion is e, the groove is a circular groove, the diameter of the groove is a, and e < a.

[0006] Preferably, the brake further includes a stator core. A wire groove is provided on the stator core. The inner diameter of the wire groove is c, the groove is a circular groove, the diameter of the groove is a, and a ≤ c.

[0007] Preferably, the brake further includes a stator core. A wire groove is provided on the stator core. The axial length of the mover core is g, the axial depth of the groove is f, and the axial length of the bottom wall of the wire groove is k. (g - f) / k ≥ 0.7.

[0008] Preferably, the brake further includes a friction plate, and the friction plate is sleeved outside the annular protrusion.

[0009] Preferably, the keyway axially penetrates the rotating hub.

[0010] Preferably, the brake further includes a mounting shaft. The rotating hub is mounted on the mounting shaft and is connected to the mounting shaft through a connection key.

[0011] Preferably, the brake further includes a stator core. A wire groove is provided on the stator core. A stator winding is provided in the wire groove. A brake spring is installed between the stator core and the mover core.

[0012] Preferably, one end of the stator core facing the mover core is provided with a guide post, and a guide groove is provided on the mover core. The guide post is slidably arranged in the guide groove.

[0013] According to another aspect of the present application, a motor is provided, including a brake, which is the above-mentioned brake.

[0014] The brake provided by the present application includes a rotating hub and a rotor core. An annular protrusion is provided at one end of the rotating hub facing the rotor core. A keyway is provided on the inner peripheral wall of the annular protrusion. A groove is provided at one end of the rotor core facing the rotating hub. The annular protrusion is installed in the groove. This brake uses the part with low magnetic field utilization rate on the rotor core to form a groove as an avoidance space. While reducing the influence on the magnetic field density of the brake, it can increase the axial length of the keyway provided on the rotating hub. And this increased axial length is accommodated in the groove of the rotor core in the form of an annular protrusion. On the basis of reducing the total axial length of the rotating hub and the rotor core, it can ensure the length of the keyway, thereby ensuring that the connecting key has sufficient connection length and ensuring the connection reliability of the connecting key. Therefore, it can effectively reduce the volume of the brake, reduce the volume of the motor, and improve the power density of the motor. Description of the Drawings

[0015] Figure 1 It is a schematic exploded view of the brake according to an embodiment of the present application;

[0016] Figure 2 It is a schematic exploded view of the brake according to an embodiment of the present application;

[0017] Figure 3 It is a schematic dimensional structure diagram of the brake according to an embodiment of the present application;

[0018] Figure 4 It is a schematic three-dimensional structure diagram of the rotating hub of the brake according to an embodiment of the present application;

[0019] Figure 5 It is a schematic three-dimensional structure diagram of the rotating hub of the brake according to an embodiment of the present application;

[0020] Figure 6 It is a schematic three-dimensional structure diagram of the rotor core of the brake according to an embodiment of the present application;

[0021] Figure 7 It is a schematic three-dimensional structure diagram of the rotor core of the brake according to an embodiment of the present application;

[0022] Figure 8 It is a schematic cross-sectional structure diagram of the brake according to an embodiment of the present application;

[0023] Figure 9 It is the relationship between the output torque T and a / c of the brake according to an embodiment of the present application;

[0024] Figure 10The relationship between the output torque T of the brake according to an embodiment of the present application and (g - f) / k;

[0025] Figure 11 Schematic diagram of the exploded structure of the brake in the related art;

[0026] Figure 12 Schematic diagram of the structure of the brake in the related art;

[0027] Figure 13 Schematic cross-sectional view of the brake in the related art;

[0028] Figure 14 Magnetic circuit path diagram of the brake in the related art;

[0029] Figure 15 Magnetic field magnetic density distribution diagram of the brake in the related art.

[0030] The reference numerals are shown as:

[0031] 1, rotating hub; 2, rotor core; 3, annular protrusion; 4, keyway; 5, groove; 6, stator core; 7, wire groove; 8, friction plate; 9, mounting shaft; 10, stator winding; 11, connecting key; 12, brake spring; 13, guide post; 14, guide groove. Detailed implementation manners

[0032] Referring to Figures 11 to 15 As shown, in the related art, the motor structure includes bearings, end covers, housings, stators, rotors, bearings, end covers, brakes, shafts, encoders, end covers, etc.

[0033] The brake includes a rotating hub 1, a rotor core 2, a stator core 6, a connecting key 11, etc. After the rotating hub 1 is bonded to the friction plate, it is fixed to the mounting shaft 9 through the connecting key 11 to form a rotating body, and the stator core 6 is fixed to the motor end cover.

[0034] The schematic plan view of the installation of the brake on the mounting shaft 9 is as shown in Figure 12 As shown. Since the driving force between the rotating hub 1 and the mounting shaft 9 is transmitted through the connecting key, when the output torque of the brake is constant, the length W of the connecting key 11 must meet the structural strength requirements. When the length W does not meet the requirements, it will cause problems with the connection reliability between the brake and the mounting shaft 9. Therefore, in order to ensure that the connecting key has a sufficient length W, the rotating hub 1 also needs to have a sufficient axial length to meet the installation requirements of the connecting key 11.

[0035] When the stator winding is de-energized, the brake pushes the rotor core 2 to contact with the friction plate through the spring force F1. The extrusion force between the friction plate and the rotor core 2 is equal to the brake spring force F1. The extrusion force and the friction coefficient between the friction plate and the rotor core 2 act together to generate a braking torque, and the braking torque acts on the rotating body to finally achieve the braking of the motor. When the stator winding is energized, an electromagnetic field is generated by the current. The brake structure involved in the electromagnetic field is the stator core 6 and the rotor core 2, and the magnetic circuit direction is as Figure 14 shown. The generated electromagnetic force F2 overcomes the spring force F1, and finally pulls the rotor core 2 to fit with the stator core 6, finally realizing the separation of the rotor core 2 from the friction plate of the brake. The rotating body is no longer subject to the braking effect, and the mounting shaft 9 rotates freely.

[0036] During the research process, the applicant found that the magnetic field distribution of the brake is related to the structure of the magnetic circuit system composed of the stator core 6 and the rotor core 2 of the brake. The magnetic flux density distribution of the brake magnetic field is as Figure 15 shown. In the figure, the magnetic field density is low at the position on the rotor core 2 close to the rotating hub 1 and close to the shaft hole, and the magnetic field utilization rate at this position is low.

[0037] The part with a low magnetic field utilization rate on the rotor core 2 is connected to the part where the connecting key 11 is installed on the rotating hub 1. Therefore, the rotating hub 1 and the rotor core 2 can be further improved and designed according to the part with a low magnetic field utilization rate on the rotor core 2, so as to achieve the purpose of reducing the length of the brake bearing and further reducing the volume of the brake.

[0038] Combined with reference to Figures 1 to 10 shown, according to the embodiment of the present application, the brake includes a rotating hub 1 and a rotor core 2. An annular protrusion 3 is provided at one end of the rotating hub 1 facing the rotor core 2. A key groove 4 is provided on the inner peripheral wall of the annular protrusion 3. A groove 5 is provided at one end of the rotor core 2 facing the rotating hub 1. The annular protrusion 3 is installed in the groove 5.

[0039] Through the above structural analysis, it can be seen that the part with a low magnetic field utilization rate on the rotor core 2 exactly corresponds to the part where the key groove 4 is provided on the rotating hub 1. Since this part of the region on the rotor core 2 has little influence on the magnetic field utilization rate, even if this part is cut off, it will not affect the overall magnetic field utilization rate on the rotor core 2. And the groove 5 formed after cutting off this part can just be used to increase the axial length of the key groove 4 on the rotating hub 1. The increased axial length of this part can be accommodated in the groove 5 by adopting the annular protrusion 3. Under the condition of ensuring that the connecting key 11 has enough axial length, the total axial length of the rotating hub 1 and the rotor core 2 can be effectively shortened, and then the purpose of shortening the length of the brake can be achieved. The present application is improved based on this idea.

[0040] The brake according to the embodiment of the present application utilizes the part with low magnetic field utilization rate on the mover core 2 to form a groove 5 as an avoidance space. While reducing the influence on the magnetic field density of the brake, it can increase the axial length of the keyway 4 provided on the rotating hub 1. And this increased axial length is accommodated in the groove 5 of the mover core 2 in the form of an annular protrusion 3. On the basis of reducing the total axial length of the rotating hub 1 and the mover core 2, it can ensure the length of the keyway 4, thereby ensuring that the connecting key 11 has sufficient connection length and ensuring the connection reliability of the connecting key 11. Therefore, it can effectively reduce the volume of the brake, reduce the volume of the motor, and improve the power density of the motor.

[0041] In one embodiment, the outer diameter of the annular protrusion 3 is e, the groove 5 is a circular groove, and the diameter of the groove 5 is a, and e < a, so as to ensure that the annular protrusion 3 can penetrate into the groove 5 of the mover core 2 of the brake, and the designed gap between the groove 5 and the annular protrusion 3 can ensure that there is no interference between the rotating hub 1 and the mover core 2 of the brake, and ensure the normal and effective operation of the rotating hub 1. The above annular protrusion 3 can be circular, elliptical, or other shapes, and the shape of the groove 5 is adapted to the shape of the annular protrusion 3 and can be adjusted adaptively according to the shape of the annular protrusion 3.

[0042] For the brake, when there is no groove 5 on the mover core 2 of the brake, the output torque of the brake is T0, and when there is a groove 5, the output torque is T. The influence of the groove 5 on the mover core 2 of the brake on the output torque of the brake is related to the structure of the entire magnetic circuit system. The structural dimensions of the stator core 6 and the mover core 2 of the brake will affect the magnetic field density distribution. When the groove dimensions are certain, the output torque of the brake corresponding to different structures of the stator core 6 and the mover core 2 of the brake will have large fluctuations.

[0043] In one embodiment, the brake further includes a stator core 6. A wire groove 7 is provided on the stator core 6. The inner diameter of the wire groove 7 is c, the groove 5 is a circular groove, and the diameter of the groove 5 is a, and a ≤ c. There are two concentrated regions in the magnetic field of the mover core of the brake, namely concentrated region 1 and concentrated region 2, and the distribution is as Figure 15As shown. Based on the analysis of the brake magnetic field path, the contour of the inner diameter c of the winding groove of the stator core 6 of the brake is within the axial space range corresponding to the magnetic field concentration area of the rotor core 2 of the brake. That is to say, the larger the inner diameter c of the winding groove of the stator core 6 of the brake, the larger the distribution diameter of the magnetic field concentration area 1 of the rotor core 2 of the brake, that is, the position of the magnetic field concentration area of the rotor core 2 of the brake follows the change of the size of the inner diameter c of the winding groove of the stator core 6 of the brake. According to the relationship between the electromagnetic field and the electromagnetic force, the groove 5 of the rotor core 2 of the brake cannot be in the magnetic field concentration area 1. If the position of the groove 5 is in the magnetic field concentration area 1, the output torque of the brake will be affected. The relationship between the brake output torque T and a / c is as Figure 9 shown. It can be seen from the figure that when a ≤ c, the groove structure has basically no influence on the brake output torque, and when a > c, the brake output torque decreases significantly.

[0044] In one embodiment, the brake further includes a stator core 6. A wire groove 7 is provided on the stator core 6. The axial length of the rotor core 2 is g, the axial depth of the groove 5 is f, and the axial length of the bottom wall of the wire groove 7 is k, and (g - f) / k ≥ 0.7.

[0045] The stator core 6 of the brake and the rotor core 2 of the brake together form the magnetic flux path of the brake magnetic field. The magnetic field directions of the stator core 6 of the brake and the rotor core 2 of the brake are as Figure 14 shown. The magnetic field directions at the bottom of the stator of the brake and the rotor are radial, and the magnetic field directions at the bottom of the stator of the brake and the rotor are opposite. From the analysis of the brake principle and the corresponding relationship between the magnetic field and the electromagnetic force, it can be known that when there is no groove 5 in the rotor core 2 of the brake, when the bottom thickness k of the wire groove 7 of the brake stator is basically the same as the size of the brake rotor thickness, the magnetic field distribution of the brake rotor and the brake stator is the most uniform, and the output torque is the largest.

[0046] When the groove 5 is provided in the rotor core 2 of the brake, g - f represents the thickness of the brake rotor corresponding to the bottom of the groove 5 of the rotor core 2 of the brake, represents the ratio of the thickness of the brake rotor corresponding to the bottom of the groove 5 of the rotor core 2 of the brake to the thickness of the bottom of the brake stator, When the value is small, it means that the thickness of the brake rotor corresponding to the bottom of the groove 5 of the rotor core 2 of the brake is smaller than the thickness of the bottom of the brake stator, which will cause the magnetic field distribution of the brake stator and the brake rotor to be uneven, and further cause the brake output torque to decrease. After theoretical analysis, the relationship between the brake output torque T and is as Figure 10 shown. It can be seen from the figure that when the groove structure has basically no influence on the brake output torque, and when The output torque of the brake decreases significantly at this time.

[0047] In one embodiment, the brake further includes a friction plate 8, and the friction plate 8 is sleeved outside the annular protrusion 3.

[0048] In one embodiment, the keyway 4 axially penetrates through the rotating hub 1, so as to ensure that the connecting key 11 can have the maximum length, and more effectively ensure the connection strength and connection reliability between the rotating hub 1 and the mounting shaft 9.

[0049] In one embodiment, the brake further includes a mounting shaft 9, and the rotating hub 1 is mounted on the mounting shaft 9 and is connected to the mounting shaft 9 through a connecting key 11.

[0050] In one embodiment, the brake further includes a stator core 6. A wire groove 7 is provided on the stator core 6, and a stator winding 10 is provided in the wire groove 7. A brake spring 12 is installed between the stator core 6 and the rotor core 2.

[0051] In one embodiment, a guide post 13 is provided at one end of the stator core 6 facing the rotor core 2, a guide groove 14 is provided on the rotor core 2, and the guide post 13 is slidably arranged in the guide groove 14.

[0052] According to an embodiment of the present application, the motor includes a brake, and the brake is the above-mentioned brake.

[0053] It is easy for those skilled in the art to understand that, on the premise of not conflicting, the above-mentioned advantageous ways can be freely combined and superimposed.

[0054] The above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above is only the preferred implementation manner of the present application. It should be noted that for those of ordinary skill in the art, several improvements and modifications can be made without departing from the technical principle of the present application, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A brake, characterized in that, It includes a rotating hub (1) and a rotor core (2). An annular protrusion (3) is provided at one end of the rotating hub (1) facing the rotor core (2). A keyway (4) is provided on the inner peripheral wall of the annular protrusion (3). A groove (5) is provided at one end of the rotor core (2) facing the rotating hub (1). The annular protrusion (3) is installed in the groove (5). The brake further includes a stator core (6). A wire groove (7) is provided on the stator core (6). The axial length of the rotor core (2) is g, the axial depth of the groove (5) is f, and the axial length of the bottom wall of the wire groove (7) is k, and (g - f) / k ≥ 0.

7.

2. The brake according to claim 1, characterized in that, The outer diameter of the annular protrusion (3) is e. The groove (5) is a circular groove, and the diameter of the groove (5) is a, and e < a.

3. The brake according to claim 1, characterized in that, The inner diameter of the wire groove (7) is c. The groove (5) is a circular groove, and the diameter of the groove (5) is a, and a ≤ c.

4. The brake according to any one of claims 1 to 3, characterized in that, The brake further includes a friction plate (8). The friction plate (8) is sleeved outside the annular protrusion (3).

5. The brake according to any one of claims 1 to 3, characterized in that, The keyway (4) axially penetrates through the rotating hub (1).

6. The brake according to any one of claims 1 to 3, characterized in that, The brake further includes a mounting shaft (9). The rotating hub (1) is mounted on the mounting shaft (9) and is connected to the mounting shaft (9) through a connection key (11).

7. The brake according to claim 1, wherein A stator winding (10) is provided in the wire groove (7). A brake spring (12) is installed between the stator core (6) and the rotor core (2).

8. The brake according to claim 7, characterized in that, A guide post (13) is provided at one end of the stator core (6) facing the rotor core (2). A guide groove (14) is provided on the rotor core (2). The guide post (13) is slidably arranged in the guide groove (14).

9. A motor, comprising a brake, characterized in that, The brake is the brake according to any one of claims 1 to 8.

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