Salient pole magnetic circuit permanent magnet brake joint module and assembling method thereof

Abstract

The invention discloses a salient pole magnetic circuit permanent magnet brake joint module and an assembling method thereof. The salient pole magnetic circuit permanent magnet brake joint module comprises a shell, a main shaft, a motor stator, a motor rotor, a brake stator and a brake rotor. The shell comprises an annular cover, an inner cylinder and an outer cylinder, wherein the inner cylinder and the outer cylinder are fixed to the inner ring face and the outer ring face of the shell. An interlayer cavity with one open end and one closed end is defined by the inner cylinder, the outer cylinder and the annular cover. The main shaft is rotationally connected with the inner ring of the inner cylinder, the braking end and the ring cover are distributed on the same side and extend out of the inner cylinder, and the end, away from the ring cover, of the main shaft is an output end; the motor stator is arranged in the opening end of the interlayer cavity and is fixed on the inner side wall of the outer cylinder; the motor rotor is arranged in the inner ring of the motor stator and connected with the main shaft; the brake stator is encapsulated in the closed end of the interlayer cavity through glue and is connected with the end face of the motor stator. The motor and the brake are integrated, the axial space of the structure is saved, and meanwhile the braking torque between the brake stator and the brake rotor is improved.

Description

Technical Field

[0001] This invention relates to the field of humanoid robot technology, specifically to a salient pole magnetic circuit permanent magnet braking joint module and its assembly method. Background Technology

[0002] Currently, the joint modules of humanoid robots generally use permanent magnet power-off brakes as safety holding devices. Their core function is to achieve mechanical self-locking through the magnetic force generated by the permanent magnet in the power-off state, so as to prevent the joint position from shifting.

[0003] In existing technologies, permanent magnet power-off brakes are mainly traditional external brakes and split-type electromagnetic brakes. Traditional external brakes, such as standard parts provided by manufacturers like KEB, suffer from excessively large axial lengths (typically greater than 15mm) and limited central through-hole dimensions, making them difficult to adapt to the compact requirements of joint modules. Traditional brakes are prone to heat accumulation; excessively high temperatures can cause irreversible demagnetization of the permanent magnets, leading to a decrease in braking force. Furthermore, high temperatures cause uneven contact surfaces on the brake friction pads, exacerbating abnormal wear. High coil temperatures accelerate the carbonization of the insulation layer, increasing the risk of short circuits and making it difficult to meet the high-frequency start-stop requirements of humanoid robots. Split-type electromagnetic brakes require independent power supplies and have complex heat dissipation structures. Even though the thickness of the Jushunfeng ultra-thin brake has been optimized, additional heat dissipation design is still needed, leading to increased system energy consumption.

[0004] In addition, existing permanent magnet power failure brakes require a larger current to maintain torque, and the coils inside the permanent magnet power failure brake occupy a large space, which significantly increases the power consumption of the joint module and the axial length of the joint module, reducing the robot's endurance. Summary of the Invention

[0005] This invention proposes a salient pole magnetic circuit permanent magnet braking joint module and its assembly method to solve the problems of excessive axial length and high power consumption of joint modules equipped with brakes.

[0006] On one hand, the present invention discloses a salient pole magnetic circuit permanent magnet braking joint module, including a housing, a main shaft, a motor stator, a motor rotor, a brake stator, and a brake rotor; The housing includes a ring cover and an inner cylinder and an outer cylinder fixed on its inner and outer ring surfaces. The inner cylinder, the outer cylinder and the ring cover enclose a sandwich cavity with one end open and the other end closed. The main shaft is rotatably connected to the inner ring of the inner cylinder. Its braking end is distributed on the same side as the ring cover and extends to the outside of the inner cylinder. Its end away from the ring cover is the output end. The motor stator is disposed in the open end of the sandwich cavity and fixed on the inner side wall of the outer cylinder; the motor rotor is placed in the inner ring of the motor stator and connected to the main shaft; the brake stator is sealed in the closed end of the sandwich cavity by glue, and the end face of the motor stator near the ring cover is in contact with the glue. The brake stator includes a shielding plate, an inner ring frame, a retainer, an outer ring frame, and a coil connected sequentially along the main shaft axis; the shielding plate is fixed to the end face of the motor stator; the outer ring frame is placed outside the inner ring frame, and the two ring frames form an mounting interlayer for mounting the coil; the salient poles of the two ring frames are arranged along the main shaft axis and extend through the ring cover to the outside of the housing; both ring frames are made of high magnetic permeability material; a first permanent magnet is provided between the two ring frames, and the first permanent magnet is located inside the retainer. The brake rotor includes a fixed base located outside the housing and connected to the braking end of the main shaft. An armature is provided between the fixed base and the ring cover. The armature is connected to the fixed base via a spring clip, and a second permanent magnet is provided inside the armature. By integrating the motor and the brake into one unit, the axial space of the structure is saved while the braking torque between the brake stator and the brake rotor is increased.

[0007] Optionally, the salient poles of the inner ring frame are distributed at equal angles around the axis of the main shaft; the salient poles of the outer ring frame are distributed at equal angles around the axis of the main shaft and are arranged opposite to the salient poles of the inner ring frame; the first permanent magnet is distributed at equal angles around the axis of the main shaft and is arranged opposite to the salient poles of the inner ring frame; the second permanent magnet is distributed at equal angles around the axis of the main shaft and is distributed between the salient poles of the inner ring frame and the salient poles of the retainer. The inner ring frame includes an inner ring body arranged along the axial direction of the main shaft, one end of the inner ring body is provided with a convex pole, and the outer ring of the other end is provided with a first connecting plate; the outer ring frame includes an outer ring body arranged along the axial direction of the main shaft, one end of the outer ring body is provided with a convex pole, and the inner ring of the other end is provided with a second connecting plate; the first connecting plate, the retainer and the second connecting plate are fixed together by bolts; The first and second permanent magnets are made of sintered neodymium iron boron; the cage is made of a non-magnetic material. Using the above scheme, the brake stator, through a high-permeability material and a salient pole structure, achieves low power consumption, low energy consumption, and high torque in the interaction between the brake stator and the brake rotor, thus reducing the power consumption of the joint module.

[0008] Optionally, the end face of the inner ring bracket protrusion is flush with the end face of the retainer protrusion, and the height difference between the inner ring bracket protrusion and the outer wall of the ring cover is 2mm to 5mm. This design allows the protrusion to better engage with the armature.

[0009] Optionally, the housing is a single-piece structure; The outer ring of the brake stator, the inner wall of the ring cover, the inner wall of the outer cylinder, and the end face of the motor stator form a first potting area. The inner ring of the brake stator, the inner wall of the ring cover, and the outer ring of the inner cylinder form a second potting area. A connecting channel is provided between the brake stator and the inner wall of the ring cover to connect the first potting area and the second potting area. The ring cover has a through hole for the salient pole to pass through and a wire hole for the cable to pass through; the adhesive is suitable for being injected into the first potting area through the wire hole so that the brake stator and the motor stator are both potted at the closed end of the interlayer cavity; the adhesive is an epoxy resin material. The housing is made of aluminum alloy. Using the above method, the brake stator and motor stator are encapsulated within the housing, resulting in good heat dissipation.

[0010] Optionally, the inner side of the ring cover is provided with a retaining block, which is distributed at equal angles to the outer wall of the inner cylinder with the axis of the main shaft as the center; the retaining block is adapted to position the inner ring of the inner ring frame. Using the above solution, Optionally, the spring is connected to the armature by a first bolt; the first bolts are evenly distributed around the axis of the main shaft; a second bolt is provided between two adjacent first bolts, and the second bolt connects the spring to the fixed seat; the spring is made of an elastic material. This design allows the spring to reset the armature when the brake stator and brake rotor are unlocked.

[0011] Optionally, the end of the inner cylinder away from the ring cover extends to the middle section of the outer cylinder; The end of the motor rotor near the ring cover is placed between the inner cylinder and the outer cylinder, and the end of the motor rotor away from the ring cover is the connecting end. The connecting end of the motor rotor is placed inside the outer cylinder and exposed outside the inner cylinder. The main shaft includes a hollow shaft and a connecting frame, bearings and bushings arranged sequentially along the axial direction of the hollow shaft; The hollow shaft is connected to the inner ring of the inner cylinder via the bearing; the hollow shaft and the connecting frame are an integral structure; the hollow shaft is connected to the inner ring of the motor rotor via the connecting frame; the braking end of the hollow shaft is connected to the bushing; one end of the bushing extends to the inner ring of the inner cylinder and abuts against the adjacent bearing, and the other end of the bushing extends outside the housing and is connected to the fixed seat. Using the above solution, the fixed seat and the hollow shaft are connected via the bushing, simplifying the installation process.

[0012] Optionally, there are two bearings, including a first bearing adjacent to the bushing and a second bearing adjacent to the connecting frame; The two end faces of the first bearing abut against the end face of the bushing and the first stepped surface of the inner cylinder, respectively. The connecting bracket has an annular groove on the side near the bushing. The second bearing is partially placed within the annular groove, and the two end faces of the second bearing abut against the second stepped surface of the inner cylinder and the stepped surface of the hollow shaft, respectively. This design shortens the axial length of the main shaft, thereby shortening the axial length of the joint module.

[0013] On the other hand, the assembly method of the salient pole magnetic circuit permanent magnet braking joint module disclosed in this invention includes the following steps: S1: Install the brake stator and motor stator in the sandwich cavity of the housing to obtain a half-finished product; S2: Insert the auxiliary tooling coated with release agent into the opening end of the interlayer cavity of the shell so that the sealing end of the auxiliary tooling is placed between the motor stator and the inner cylinder; heat the auxiliary tooling so that the sealing end is interference-fitted with the inner cylinder and the motor stator; wherein, the heating temperature is 110℃~130℃; S3: Place the semi-finished product equipped with auxiliary tooling into the glue injection equipment for glue injection and potting; after the glue has cured, separate the auxiliary tooling from the semi-finished product at room temperature. S4: Assemble the motor rotor and main shaft onto the semi-finished product, and install the brake rotor on the brake end of the main shaft.

[0014] Optionally, the auxiliary tooling is arranged along the axial direction of the main shaft, and its two ends are divided into a sealing end composed of a sealing ring and a connecting end composed of a connecting flange. The inner ring of the brake stator, the inner wall of the ring cover, the outer ring of the inner cylinder, and the end face of the sealing ring form a second potting area; The connecting flange is adapted to be fixed by screws to the end face of the outer cylinder away from the ring cover.

[0015] By adopting the above technical solution, the present invention has the following advantages compared with the prior art: The brake stator uses high magnetic permeability material and salient pole structure to make the brake stator and brake rotor have low power consumption, low power consumption and high torque, which reduces the power consumption of the salient pole magnetic circuit permanent magnet brake joint module. This is conducive to achieving a longer endurance of the salient pole magnetic circuit permanent magnet brake joint module and humanoid robot and adapting to the working environment of humanoid robot with frequent start and stop. By encapsulating the brake stator and motor stator inside the housing, the heat dissipation performance is good, the assembly difficulty of the brake stator is reduced, the installation space is saved, and the axial length of the salient pole magnetic circuit permanent magnet brake joint module is reduced. By setting a spring between the armature and the fixed base, the axial length of the brake rotor is shortened, resulting in a smaller volume and facilitating the realization of a permanent magnet brake joint module with a salient pole magnetic circuit and a smaller axial length. This salient pole magnetic circuit permanent magnet brake joint module integrates the motor and brake into one unit, saving axial space while increasing the braking torque between the brake stator and the brake rotor.

[0016] The above description of the disclosure and the following description of the embodiments are intended to demonstrate and explain the spirit and principles of the present invention, and to provide a further explanation of the scope of the patent application of the present invention. Attached Figure Description

[0017] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0018] Figure 1 This is an exploded view of the salient pole magnetic circuit permanent magnet braking joint module in this invention; Figure 2 This is a cross-sectional view of the salient pole magnetic circuit permanent magnet braking joint module in this invention; Figure 3 This is an exploded view of the brake stator in this invention; Figure 4 This is an exploded schematic diagram of the brake rotor in this invention; Figure 5 This is a schematic diagram of the housing in this invention; Figure 6 This is a schematic diagram of the self-locking of the brake stator and brake rotor in this invention; Figure 7 This is a schematic diagram illustrating the unlocking of the brake stator and brake rotor in this invention; Figure 8 This is a schematic diagram of the semi-finished product and auxiliary tooling in this invention; Figure 9 This is a schematic diagram of the auxiliary tooling in this invention.

[0019] Explanation of icon numbers: 1. Shell; 11. Ring cover; 111. Through hole; 112. Wire hole; 12. Inner cylinder; 13. Outer cylinder; 14. Clamping block; 2. Main spindle; 21. Hollow shaft; 22. Connecting bracket; 23. Bearing; 24. Bushing; 25. Annular groove; 3. Motor stator; 4. Motor rotor; 5. Brake stator; 51. Shielding plate; 52. Inner ring frame; 53. Cage; 54. Outer ring frame; 55. Coil; 56. First permanent magnet; 6. Brake rotor; 61. Mounting base; 62. Armature; 63. Spring; 64. Second permanent magnet; 65. First bolt; 66. Second bolt; 7. Auxiliary tooling; 71. Sealing ring; 72. Connecting flange. Detailed Implementation

[0020] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Although the description of the present invention will be presented in conjunction with preferred embodiments, this does not mean that the features of the invention are limited to this embodiment. On the contrary, the purpose of describing the invention in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of the present invention. To provide a deep understanding of the present invention, many specific details will be included in the following description. The present invention may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of the present invention, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0021] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of the invention is usually placed in during use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0022] The terms “first”, “second”, etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0023] In the description of this embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "provided with," "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.

[0024] On one hand, the present invention provides a salient-pole magnetic circuit permanent magnet braking joint module, suitable for application in humanoid robots. This salient-pole magnetic circuit permanent magnet braking joint module is a joint module with a permanent magnet de-energized brake designed with a salient-pole magnetic circuit.

[0025] Please see Figures 1-2As shown, the salient pole magnetic circuit permanent magnet brake joint module includes a housing 1, a main shaft 2, a motor stator 3, a motor rotor 4, a brake stator 5, and a brake rotor 6. In this embodiment, the housing 1, main shaft 2, motor stator 3, motor rotor 4, brake stator 5, and brake rotor 6 are all coaxially arranged. In this embodiment, the salient pole magnetic circuit permanent magnet brake joint module is vertically arranged. The brake rotor 6, brake stator 5, and motor stator 3 are arranged sequentially from top to bottom.

[0026] The housing 1 includes a ring cover 11 and an inner cylinder 12 and an outer cylinder 13 fixed to the inner and outer annular surfaces of the ring cover 11. The inner cylinder 12, outer cylinder 13, and ring cover 11 enclose a sandwich cavity with one end open and the other closed. In this embodiment, the housing 1 is a one-piece structure. The housing 1 is made of aluminum alloy for better heat dissipation. The ring cover 11 is connected to the top of the inner cylinder 12 and the top of the outer cylinder 13, respectively. The upper end of the sandwich cavity is a closed end, and the lower end of the sandwich cavity is an open end.

[0027] The main shaft 2 is rotatably connected to the inner ring of the inner cylinder 12. The main shaft 2 has a braking end and an output end arranged opposite each other. The braking end of the main shaft 2 is distributed on the same side as the ring cover 11 and extends to the outside of the inner cylinder 12. The end of the main shaft 2 furthest from the ring cover 11 is the output end, which is suitable for connection to a reduction mechanism. The motor stator 3 is disposed in the open end of the interlayer cavity and fixed to the inner wall of the outer cylinder 13. The motor rotor 4 is placed in the inner ring of the motor stator 3 and connected to the main shaft 2.

[0028] The brake stator 5 is sealed in the closed end of the sandwich cavity with adhesive, and the end face of the motor stator 3 near the ring cover 11 (i.e., the upper end face of the motor stator 3) is in contact with the adhesive. The brake stator 5 is fixed to the upper end face of the motor stator 3. The adhesive can effectively fix the brake stator 5 and also be used to dissipate heat from the motor stator 3. The brake rotor 6 is located outside the housing 1 and is connected to the braking end of the main shaft 2.

[0029] Please see Figures 2-3 As shown, the brake stator 5 includes a shielding plate 51, an inner ring frame 52, a retainer 53, an outer ring frame 54, and a coil 55, which are sequentially connected along the axial direction of the main shaft 2. In this embodiment, the shielding plate 51, the inner ring frame 52, the retainer 53, the outer ring frame 54, and the coil 55 are connected sequentially from bottom to top. The shielding plate 51 is fixed to the upper end surface of the motor stator 3. The outer ring frame 54 is located outside the inner ring frame 52. The two ring frames (i.e., the outer ring frame 54 and the inner ring frame 52) form a mounting interlayer for mounting the coil 55. The upper ends of both ring frames are provided with salient poles. The salient poles of both ring frames are arranged along the axial direction of the main shaft 2 and extend through the ring cover 11 to the outside of the housing 1. A first permanent magnet 56 is provided between the two ring frames. The first permanent magnet 56 is located inside the retainer 53.

[0030] The first potting area is formed by the outer ring of the brake stator 5, the inner wall of the ring cover 11, the inner wall of the outer cylinder 13, and the upper end face of the motor stator 3. The second potting area is formed by the inner ring of the brake stator 5, the inner wall of the ring cover 11, and the outer ring of the inner cylinder 12. A connecting channel is provided between the brake stator 5 and the inner wall of the ring cover 11 to connect the first and second potting areas. The ring cover 11 has a through hole 111 for the salient pole to pass through and a wire hole 112 for the cable to pass through. Adhesive is suitable for injection into the first potting area through the wire hole 112 so that the tops of the brake stator 5 and the motor stator 3 are both potted at the closed end of the interlayer cavity. In this embodiment, the adhesive is epoxy resin.

[0031] Please see Figure 2 and Figure 4 As shown, the brake rotor 6 includes a fixed base 61, an armature 62, a spring 63, and a second permanent magnet 64. The fixed base 61 is located outside the housing 1 and is connected to the braking end of the main shaft 2. The armature 62 is provided between the fixed base 61 and the ring cover 11. The armature 62 is connected to the fixed base 61 through the spring 63. The second permanent magnet 64 is provided inside the armature 62. In this embodiment, the spring 63 is connected to the armature 62 through a first bolt 65. The first bolts 65 are evenly distributed around the axis of the main shaft 2. A second bolt 66 is provided between two adjacent first bolts 65. The second bolt 66 connects the spring 63 to the fixed base 61. The spring 63 can be a single piece or multiple pieces. In this embodiment, the spring 63 is a single piece.

[0032] In this embodiment, the shielding plate 51 is made of ferromagnetic material to prevent the magnetic fields of the motor stator 3 and motor rotor 4 from interfering with the magnetic field of the brake stator 5.

[0033] In this embodiment, both the inner ring frame 52 and the outer ring frame 54 are made of high magnetic permeability materials. The materials of the inner ring frame 52 and the outer ring frame 54 include, but are not limited to, hot-rolled No. 10 steel, quenched and tempered DT4 (i.e., electromagnetic pure iron), etc.

[0034] In this embodiment, the retainer 53 is made of a non-magnetic material. The material of the retainer 53 includes, but is not limited to, PTFE (i.e., polytetrafluoroethylene).

[0035] In this embodiment, the first permanent magnet 56 and the second permanent magnet 64 are made of sintered neodymium iron boron to form a permanently and continuously excited magnetic field circuit. The magnetization direction of the first permanent magnet 56 is axial, and the magnetization direction of the second permanent magnet 64 is radial.

[0036] In this embodiment, the spring 63 is made of an elastic material. The material of the spring 63 includes, but is not limited to, spring steel 65Mn, stainless steel SUS301, stainless steel SUS304, stainless steel SUS316, etc.

[0037] In this embodiment, please refer to Figure 2 As shown, the inner diameter of the shielding plate 51 is the same as the inner diameter of the inner ring frame 52, and they are coaxially arranged. The outer diameters of the shielding plate 51, the inner ring frame 52, the retainer 53, and the outer ring frame 54 are the same, and they are coaxially arranged. The inner ring frame 52 includes an inner ring body arranged axially along the main shaft 2. A convex pole is provided at the upper end of the inner ring body, and a first connecting plate is provided on the lower outer ring. The outer ring frame 54 includes an outer ring body arranged axially along the main shaft 2. A convex pole is provided at the upper end of the outer ring body, and a second connecting plate is provided on the lower inner ring. The first connecting plate, the retainer 53, and the second connecting plate are fixed together by bolts.

[0038] Furthermore, the salient poles of the inner ring frame 52 are distributed at equal angles around the axis of the main shaft 2. The salient poles of the outer ring frame 54 are distributed at equal angles around the axis of the main shaft 2 and are positioned opposite to the salient poles of the inner ring frame 52. The first permanent magnet 56 is distributed at equal angles around the axis of the main shaft 2 and is positioned opposite to the salient poles of the inner ring frame 52. The second permanent magnet 64 is distributed at equal angles around the axis of the main shaft 2 and is located between the salient poles of the inner ring frame 52 and the salient poles of the retainer 53. The length of the second permanent magnet 64 is greater than the length of both the salient poles of the inner ring frame 52 and the salient poles of the outer ring frame 54, to ensure that the brake stator 5 can effectively engage with the second permanent magnet 64.

[0039] In this embodiment, the number of salient poles of the inner ring frame 52, the outer ring frame 54, and the first permanent magnet 56 are all the same, six in total. Preferably, the number of second permanent magnets 64 is also six. There are three first bolts 65 and three second bolts 66, and the six bolts are distributed at equal angles around the axis of the main shaft 2 so that the spring piece 63 forms a wave spring structure. Compared with the traditional spring structure, the wave spring structure saves most of the space. Compared with using a sealing ring as a rebound device, the wave spring structure has better reliability.

[0040] For further details, please refer to Figure 5 As shown, to ensure that the housing 1 can effectively position the brake stator 5, a retaining block 14 is provided on the inner side of the ring cover 11. The retaining blocks 14 are distributed at equal angles on the outer side wall of the inner cylinder 12 with the axis of the main shaft 2 as the center. The retaining blocks 14 are suitable for positioning the inner ring of the inner ring frame 52, thereby effectively positioning the brake stator 5.

[0041] In this embodiment, there are six abutment blocks 14, which are arranged opposite to the convex pole of the inner ring frame 52.

[0042] Please see Figure 2As shown, the inner cylinder 12 extends from the end away from the ring cover 11 to the middle section of the outer cylinder 13. The end of the motor rotor 4 closest to the ring cover 11 (i.e., the upper end of the motor rotor 4) is placed between the inner cylinder 12 and the outer cylinder 13, and the end of the motor rotor 4 furthest from the ring cover 11 (i.e., the lower end of the motor rotor 4) is the connecting end. The connecting end of the motor rotor 4 is placed inside the outer cylinder 13 and exposed outside the inner cylinder 12. The upper end of the motor stator 3 is placed between the inner cylinder 12 and the outer cylinder 13, and the lower end of the motor stator 3 is placed inside the outer cylinder 13 and exposed outside the inner cylinder 12.

[0043] The main shaft 2 includes a hollow shaft 21, a connecting frame 22, a bearing 23, and a bushing 24. The connecting frame 22, bearing 23, and bushing 24 are sequentially arranged on the hollow shaft 21 along its axial direction. In this embodiment, the connecting frame 22, bearing 23, and bushing 24 are arranged from bottom to top. The hollow shaft 21 has an axial center hole for the robot's cables to pass through and run.

[0044] The hollow shaft 21 is connected to the inner ring of the inner cylinder 12 via the bearing 23. The hollow shaft 21 and the connecting frame 22 are an integral structure. The hollow shaft 21 is connected to the inner ring of the connecting end of the motor rotor 4 via the connecting frame 22. The braking end of the hollow shaft 21 (i.e., the upper end of the hollow shaft 21) is connected to the bushing 24. One end of the bushing 24 extends to the inner ring of the inner cylinder 12 and abuts against the adjacent bearing 23, while the other end of the bushing 24 extends out of the housing 1 and is connected to the fixed seat 61.

[0045] The fixed base 61 is connected to the hollow shaft 21 via a bushing 24, and a flat key is provided between the fixed base 61 and the bushing 24. During installation, the fixed base 61 is simply pressed into place without adjustment, which simplifies the installation process and reduces the machining precision required.

[0046] In this embodiment, there are two bearings 23, including a first bearing adjacent to the bushing 24 and a second bearing adjacent to the connecting frame 22. The upper and lower end faces of the first bearing abut against the lower end face of the bushing 24 and the first stepped surface of the inner cylinder 12, respectively. An annular groove 25 is formed on the side of the connecting frame 22 near the bushing 24, and the lower end of the second bearing is placed in the annular groove 25. The upper and lower end faces of the second bearing abut against the second stepped surface of the inner cylinder 12 and the stepped surface of the hollow shaft 21, respectively. Placing the second bearing in the annular groove 25 can compress the axial length of the salient pole magnetic circuit permanent magnet braking joint module, thereby reducing the volume of the salient pole magnetic circuit permanent magnet braking joint module.

[0047] In this embodiment, the working principle of the brake stator 5 and the brake rotor 6 is as follows: When coil 55 is de-energized, please refer to Figure 6As shown, the magnetic field generated by the first permanent magnet 56 forms a magnetic circuit with the inner ring frame 52 and the outer ring frame 54; the second permanent magnet 64 forms a magnetic circuit with the armature 62, and the two magnetic circuits attract each other, that is, the armature 62 is attracted by the force. Since the fixed seat 61 is axially fixed, the armature 62 drives the spring 63 to move towards the salient pole through the first bolt 65, so that the armature 62 abuts against the salient pole and achieves self-locking; at this time, the spring 63 is deformed by force, that is, the spring 63 becomes a wave spring.

[0048] When coil 55 is energized, please refer to Figure 7 As shown, the magnetic field excited by coil 55 forms an opposite loop with the original magnetic field, canceling out most of the magnetic field of the first permanent magnet 56 inside the inner ring frame 52 and the outer ring frame 54, as well as most of the magnetic field of the second permanent magnet 64 inside the armature 62. At this time, the magnetic fields excited by the first permanent magnet 56 and the second permanent magnet 64 are weakened, the attraction between the two magnetic circuits is reduced, and the armature 62 is reset under the action of the spring force of the spring piece 63, that is, the armature 62 moves away from the salient pole to achieve unlocking.

[0049] The salient pole structure helps to concentrate the magnetic field strength and improve the braking torque. The magnetic field distributed around the circumference is concentrated on the salient pole, greatly increasing the magnetic field strength of the magnetic circuit on the salient pole. The two magnetic fields attract each other, forming the braking torque without requiring additional energy. When separation is needed, a large instantaneous current is added to cancel out the magnetic field loops, causing the armature 62 to separate from the salient pole. The brake stator 5 can be controlled by a PID controller; the small current required to maintain braking is provided to the set value to keep the brake continuously open. Preferably, the salient pole structure can be designed with 6, 8, 10, or 12 salient poles, which helps to concentrate the magnetic field strength and improve the braking torque.

[0050] Compared to the large coil in traditional brakes, this invention replaces the large coil with an inner ring frame 52, an outer ring frame 54, a coil 55, and a first permanent magnet 56, effectively reducing the size of the brake stator 5. Furthermore, the power consumption of the coil 55 is significantly lower than that of the large coil in traditional brakes. The brake stator 5 and brake rotor 6 in this invention exhibit low power consumption, high torque, and low power consumption, reducing the power consumption of the salient-pole magnetic circuit permanent magnet brake joint module. This facilitates longer battery life for the salient-pole magnetic circuit permanent magnet brake joint module and humanoid robots, adapting to the frequent start-stop working environment of humanoid robots.

[0051] Furthermore, to ensure better engagement of the salient pole with the armature 62, the upper surface of the salient pole of the inner ring frame 52 is flush with the upper surface of the salient pole of the retainer 53. The height difference between the top surface of the salient pole of the inner ring frame 52 and the outer wall of the ring cover 11 (i.e., the top surface of the ring cover 11) is 2mm to 5mm. In this embodiment, the height difference between the top surface of the salient pole of the inner ring frame 52 and the outer wall of the ring cover 11 (i.e., the top surface of the ring cover 11) is 4mm.

[0052] In this embodiment, the working principle of the salient pole magnetic circuit permanent magnet braking joint module is as follows: When the main shaft 2 of the salient pole magnetic circuit permanent magnet brake joint module needs to rotate, the coil 55 is energized to unlock the brake stator 5 and the brake rotor 6. At this time, the motor stator 3 is energized, and the motor stator 3 cooperates with the motor rotor 4 to make the main shaft 2 rotate. When the main shaft 2 of the salient pole magnetic circuit permanent magnet brake joint module needs to stop rotating, the motor stator 3 is de-energized, and at the same time, the coil 55 is de-energized, so that the brake stator 5 and the brake rotor 6 can achieve self-locking.

[0053] On the other hand, the present invention also provides an assembly method for a salient pole magnetic circuit permanent magnet braking joint module.

[0054] The assembly method includes the following steps: S1: Install the brake stator 5 and the motor stator 3 in the interlayer cavity of the housing 1 to obtain a half-finished product.

[0055] S2: Insert the auxiliary tooling 7 coated with release agent into the opening end of the interlayer cavity of the shell 1 (e.g., Figure 8 As shown in the figure, the sealing end of the auxiliary tooling 7 is positioned between the motor stator 3 and the inner cylinder 12. The auxiliary tooling 7 is heated, causing it to expand and thus ensuring an interference fit between the sealing end and the inner cylinder 12 and the motor stator 3. The heating temperature is 110℃~130℃. Preferably, the heating temperature is 120℃.

[0056] In this embodiment, please refer to Figure 9 As shown, the auxiliary tooling 7 is arranged along the axial direction of the main shaft 2, and its two ends are divided into a sealing end formed by a sealing ring 71 and a connecting end formed by a connecting flange 72. The inner ring of the brake stator 5, the inner wall of the ring cover 11, the outer ring of the inner cylinder 12, and the end face of the sealing ring 71 form a second potting area. The connecting flange 72 is adapted to be fixed to the end face of the outer cylinder 13 away from the ring cover 11 by screws (i.e., fixed to the lower end face of the outer cylinder 13).

[0057] In addition, before potting, the cables of the motor stator 3 and the coil 55 must be extended to the outside of the housing 1 through the wire hole 112.

[0058] S3: Place the semi-finished product equipped with auxiliary tooling 7 into the glue injection equipment for glue injection and sealing. Specifically, the semi-finished product is set vertically, with the ring cap 11 located on top of the semi-finished product. The glue injection equipment injects glue into the first sealing area through the wire hole 112. The glue in the first sealing area is connected to the channel and discharged to the second sealing area, thereby effectively filling the closed end of the interlayer cavity with glue. When the glue filling the interlayer cavity is flush with the upper surface of the ring cap 11, the glue injection is stopped.

[0059] After that, the semi-finished product equipped with auxiliary tooling 7 is placed in an oven to cure the adhesive.

[0060] After the adhesive has cured, separate the auxiliary tooling 7 from the semi-finished product at room temperature.

[0061] S4: Assemble the motor rotor 4 and the main shaft 2 onto the semi-finished product, and install the brake rotor 6 on the brake end of the main shaft 2.

[0062] The brake stator 5 and motor stator 3 are encapsulated within the housing 1. The encapsulating adhesive is made of epoxy resin with excellent heat dissipation properties, providing comprehensive encapsulation and significantly increasing the heat dissipation area. Heat transfer occurs between the motor stator 3 and the cured encapsulating adhesive, and between the cured encapsulating adhesive and the housing 1. Heat transfer also occurs between the brake stator 5 and the cured encapsulating adhesive.

[0063] In this embodiment, a rear cover is adapted to be installed on the outer top of the ring cover 11. The rear cover is disposed on the ring cover 11, and the controller of the motor stator 3 and the coil 55 is adapted to be fixed inside the rear cover.

[0064] In summary, this application provides a salient-pole permanent magnet braking joint module. The brake stator, made of a high-permeability material and featuring a salient-pole structure, achieves low power consumption, low energy dissipation, and high torque when the brake stator and rotor are in contact. This reduces the power consumption of the salient-pole permanent magnet braking joint module, facilitating longer battery life for both the module and the humanoid robot, and adapting to the frequent start-stop operating environment of the humanoid robot. Encapsulating the brake stator and motor stator within a housing provides excellent heat dissipation. Compared to traditional brakes, encapsulating the brake stator within the housing reduces assembly difficulty, saves installation space, and shortens the axial length of the salient-pole permanent magnet braking joint module. By incorporating a spring between the armature and the fixed base, the axial length of the brake rotor is further shortened, resulting in a smaller volume and facilitating the creation of a salient-pole permanent magnet braking joint module with a shorter axial length. This salient-pole permanent magnet braking joint module saves structural axial space while increasing the braking torque between the brake stator and rotor.

[0065] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A permanent magnet braking joint module with a salient pole magnetic circuit, characterized in that, It includes a housing (1), a main shaft (2), a motor stator (3), a motor rotor (4), a brake stator (5), and a brake rotor (6); The housing (1) includes a ring cover (11) and an inner cylinder (12) and an outer cylinder (13) fixed on its inner and outer ring surfaces. The inner cylinder (12), the outer cylinder (13) and the ring cover (11) enclose a sandwich cavity with one end open and the other end closed. The main shaft (2) is rotatably connected to the inner ring of the inner cylinder (12). Its braking end is distributed on the same side as the ring cover (11) and extends to the outside of the inner cylinder (12). Its end away from the ring cover (11) is the output end. The motor stator (3) is disposed in the open end of the interlayer cavity and fixed on the inner side wall of the outer cylinder (13); the motor rotor (4) is placed in the inner ring of the motor stator (3) and connected to the main shaft (2); the brake stator (5) is sealed in the closed end of the interlayer cavity by glue, and the end face of the motor stator (3) near the ring cover (11) is in contact with the glue; The brake stator (5) includes a shield plate (51), an inner ring frame (52), a retainer (53), an outer ring frame (54), and a coil (55) connected sequentially along the axial direction of the main shaft (2); the shield plate (51) is fixed on the end face of the motor stator (3); the outer ring frame (54) is placed outside the inner ring frame (52), and the two ring frames form an installation interlayer for the coil (55) to be installed; the salient poles of the two ring frames are arranged along the axial direction of the main shaft (2) and extend through the ring cover (11) to the outside of the housing (1); the two ring frames are made of high magnetic permeability material; a first permanent magnet (56) is provided between the two ring frames; the first permanent magnet (56) is located inside the retainer (53); The brake rotor (6) includes a fixed seat (61) located outside the housing (1) and connected to the braking end of the main shaft (2). An armature (62) is provided between the fixed seat (61) and the ring cover (11). The armature (62) is connected to the fixed seat (61) through a spring piece (63). A second permanent magnet (64) is provided inside the armature (62).

2. The salient pole magnetic circuit permanent magnet braking joint module according to claim 1, characterized in that, The convex poles of the inner ring frame (52) are distributed at equal angles with the axis of the main shaft (2) as the center; the convex poles of the outer ring frame (54) are distributed at equal angles with the axis of the main shaft (2) as the center, and are arranged opposite to the convex poles of the inner ring frame (52); the first permanent magnet (56) is distributed at equal angles with the axis of the main shaft (2) as the center, and is arranged opposite to the convex poles of the inner ring frame (52); the second permanent magnet (64) is distributed at equal angles with the axis of the main shaft (2) as the center, and is distributed between the convex poles of the inner ring frame (52) and the convex poles of the retainer (53); The inner ring frame (52) includes an inner ring body arranged axially along the main shaft (2), one end of the inner ring body is provided with a convex pole, and the outer ring of the other end is provided with a first connecting plate; the outer ring frame (54) includes an outer ring body arranged axially along the main shaft (2), one end of the outer ring body is provided with a convex pole, and the inner ring of the other end is provided with a second connecting plate; the first connecting plate, the retainer (53) and the second connecting plate are fixed together by bolts; The first permanent magnet (56) and the second permanent magnet (64) are made of sintered neodymium iron boron; the cage (53) is made of non-magnetic material.

3. The salient pole magnetic circuit permanent magnet braking joint module according to claim 1, characterized in that, The protruding end face of the inner ring frame (52) is flush with the end face of the protruding end face of the retainer (53), and the height difference between the protruding end face of the inner ring frame (52) and the outer wall of the ring cover (11) is 2mm to 5mm.

4. The salient pole magnetic circuit permanent magnet braking joint module according to claim 1, characterized in that, The shell (1) is an integral structure; The outer ring of the brake stator (5), the inner wall of the ring cover (11), the inner wall of the outer cylinder (13), and the end face of the motor stator (3) form a first potting area. The inner ring of the brake stator (5), the inner wall of the ring cover (11), and the outer ring of the inner cylinder (12) form a second potting area. A connecting channel is provided between the brake stator (5) and the inner wall of the ring cover (11) to connect the first potting area and the second potting area. The ring cover (11) has a through hole (111) for the salient pole to pass through and a wire hole (112) for the cable to pass through; the adhesive is suitable for being injected into the first potting area through the wire hole (112) so that the brake stator (5) and the motor stator (3) are both potted at the closed end of the interlayer cavity; the adhesive is an epoxy resin material; The housing (1) is made of aluminum alloy.

5. The salient pole magnetic circuit permanent magnet braking joint module according to claim 1, characterized in that, The inner side of the ring cover (11) is provided with a clamping block (14), and the clamping block (14) is distributed at equal angles on the outer side wall of the inner cylinder (12) with the axis of the main shaft (2) as the center; the clamping block (14) is suitable for positioning the inner ring of the inner ring frame (52).

6. The salient pole magnetic circuit permanent magnet braking joint module according to claim 1, characterized in that, The spring (63) is connected to the armature (62) by a first bolt (65); the first bolt (65) is distributed at equal angles with the axis of the main shaft (2) as the center; a second bolt (66) is provided between two adjacent first bolts (65), and the second bolt (66) connects the spring (63) to the fixed seat (61); the spring (63) is made of elastic material.

7. The salient pole magnetic circuit permanent magnet braking joint module according to claim 1, characterized in that, The inner cylinder (12) extends from the end away from the ring cover (11) to the middle section of the outer cylinder (13); The end of the motor rotor (4) near the ring cover (11) is placed between the inner cylinder (12) and the outer cylinder (13). The end of the motor rotor (4) away from the ring cover (11) is the connecting end. The connecting end of the motor rotor (4) is placed inside the outer cylinder (13) and exposed outside the inner cylinder (12). The main shaft (2) includes a hollow shaft (21) and a connecting frame (22), a bearing (23) and a bushing (24) arranged sequentially along the axial direction of the hollow shaft (21). The hollow shaft (21) is connected to the inner ring of the inner cylinder (12) through the bearing (23); the hollow shaft (21) and the connecting frame (22) are an integral structure; the hollow shaft (21) is connected to the inner ring of the connecting end of the motor rotor (4) through the connecting frame (22); the braking end of the hollow shaft (21) is connected to the bushing (24); one end of the bushing (24) extends to the inner ring of the inner cylinder (12) and abuts against the adjacent bearing (23); the other end of the bushing (24) extends out of the housing (1) and is connected to the fixed seat (61).

8. The salient pole magnetic circuit permanent magnet braking joint module according to claim 7, characterized in that, There are two bearings (23), including a first bearing adjacent to the bushing (24) and a second bearing adjacent to the connecting frame (22); The two end faces of the first bearing abut against the end face of the bushing (24) and the first step surface of the inner cylinder (12), respectively; The connecting frame (22) has an annular groove (25) on the side near the bushing (24). The second bearing is partially placed in the annular groove (25). The two end faces of the second bearing abut against the second step surface of the inner cylinder (12) and the step surface of the hollow shaft (21), respectively.

9. A method for assembling a salient pole magnetic circuit permanent magnet braking joint module as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S1: Install the brake stator (5) and the motor stator (3) in the interlayer cavity of the housing (1) to obtain a half-finished product; S2: Insert the auxiliary tooling (7) coated with release agent into the opening end of the interlayer cavity of the shell (1) so that the sealing end of the auxiliary tooling (7) is placed between the motor stator (3) and the inner cylinder (12); heat the auxiliary tooling (7) so that the sealing end is interference-fitted with the inner cylinder (12) and the motor stator (3); wherein the heating temperature is 110℃~130℃; S3: Place the semi-finished product equipped with auxiliary tooling (7) into the glue injection equipment and perform glue injection and sealing; after the glue has cured, separate the auxiliary tooling (7) from the semi-finished product at room temperature. S4: Assemble the motor rotor (4) and main shaft (2) onto the semi-finished product, and install the brake rotor (6) on the brake end of the main shaft (2).

10. The assembly method according to claim 9, characterized in that, The auxiliary tooling (7) is arranged along the axial direction of the main shaft (2), and its two ends are divided into a sealing end composed of a sealing ring (71) and a connecting end composed of a connecting flange (72); The inner ring of the brake stator (5), the inner wall of the ring cover (11), the outer ring of the inner cylinder (12), and the end face of the sealing ring (71) form a second potting area. The connecting flange (72) is adapted to be fixed by screws to the end face of the outer cylinder (13) away from the ring cover (11).

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