Robot joint electromagnetic brake

Abstract

The invention discloses a robot joint electromagnetic brake, relates to the technical field of robots, and is used for solving the technical problem that an existing electromagnetic brake is thick in axial size and cannot meet the requirement for high integration of humanoid robot joints. On the premise of not sacrificing the strength of a magnetic circuit or a stator, the structure is simplified, and the axial thickness of the whole machine is effectively reduced. According to the robot joint electromagnetic brake, an armature is provided with a step-shaped bent part, the protruding end of the step-shaped bent part is arranged in an inner hole of a stator and forms a positioning guide part, a friction plate and a cover plate are placed at the groove end of the step-shaped bent part, and meanwhile the friction plate and the cover plate are arranged in the stator; a stator coil is arranged on the step outer edge of the step-shaped bending part, and a torque spring is arranged between the stator coil and the armature.

Description

Technical Field

[0001] This invention relates to the field of robotics, and more particularly to an electromagnetic brake for robot joints. Background Technology

[0002] Currently, with the rise of humanoid robots and the resulting surge in demand, the need for brakes, a key component for maintaining joint posture, is inevitable. However, the contradictions between installation and space constraints are becoming increasingly prominent. The brakes used in humanoid robot joints are becoming thinner and thinner, and they need to be ready for immediate use and easy to replace. In other words, as brakes become thinner, the traditional brake structure has less and less room to compress, and the manufacturing and control of thinner parts are becoming increasingly difficult.

[0003] In the existing technology, the thickness limit of the brake structure is usually 9mm. Since it is made up of the stator, armature, friction plate, bushing and cover plate, the thickness reduction can only be achieved by compressing the thickness of the stator, armature, cover plate and friction plate to ensure the function. However, the thinner the part, the more difficult it is to process, the higher the cost, the lower the strength and the greater the risk of deformation during use. Therefore, it is not possible to compress the thickness of the part to the limit, and it is also impossible to guarantee long-term reliable use.

[0004] Therefore, how to provide a robot joint electromagnetic brake that simplifies the structure and reduces the overall axial thickness without sacrificing the strength of the magnetic circuit or stator has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide an electromagnetic brake for robot joints, which solves the technical problem that the axial thickness of existing electromagnetic brakes cannot meet the requirements of the high integration of humanoid robot joints; it can simplify the structure and effectively reduce the overall axial thickness without sacrificing the strength of the magnetic circuit or stator.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An electromagnetic brake for a robot joint includes: an armature having a stepped bend, the protruding end of which is built into the inner hole of a stator and forms a positioning guide; a friction plate and a cover plate are placed at the grooved end of the stepped bend, and the friction plate and the cover plate are built into the interior of the stator. A stator coil is provided on the outer edge of the stepped bend, and a torque spring is provided between the stator coil and the armature.

[0007] The armature and the stepped bend are integrally bent by stamping.

[0008] In practical applications, the robot joint electromagnetic brake further includes: a slotted plate, a cover plate assembled to the slotted plate by screws, and the friction plate, the armature, the torque spring, and the stator coil assembled between the cover plate and the slotted plate.

[0009] The cover plate has three ears that are equidistantly distributed along the circumference, and the ears are used to pass through the screw; the armature body has three mounting slots that are equidistantly distributed along the circumference, and the three ears are placed in the three mounting slots one by one.

[0010] Specifically, the slot has an annular groove, and the annular groove is used to place the stator coil.

[0011] Furthermore, the torque springs comprise six springs, and the six torque springs are evenly distributed along the circumference of the stator coil.

[0012] Compared with existing technologies, the electromagnetic actuator for robot joints described in this invention has the following advantages: In the electromagnetic brake for robot joints provided by this invention, the armature has a stepped bend, and the protruding end of the stepped bend is built into the inner hole of the stator to form a positioning guide. A friction plate and a cover plate are placed at the grooved end of the stepped bend, and the friction plate and cover plate are also built into the stator. Therefore, the structure can be simplified without sacrificing the magnetic circuit or stator strength, and the overall axial thickness of the machine can be effectively reduced. Since a stator coil is provided on the outer edge of the stepped bend, and a torque spring is provided between the stator coil and the armature, the stator coil can be energized. The armature is attracted to move together, and the axial movement space of the friction plate is released. When the stator coil is de-energized, the electromagnetic field gradually disappears, and the torque spring can push out the armature and press the friction plate. Thus, the bending height of the armature determines the working gap of the friction plate. At the same time, the size of the concave part is embedded in the thickness space of the friction plate and the cover plate, thereby effectively compressing the thickness of the two parts. In other words, in this application, the friction plate is placed in the armature groove space, and the whole movement releases and presses during operation. Thus, the electromagnetic brake structure can be as thin as 7mm without sacrificing the magnetic circuit or stator strength. Attached Figure Description

[0013] Figure 1 This is a cross-sectional structural schematic diagram of the electromagnetic actuator for robot joints provided in an embodiment of the present invention; Figure 2 This is an exploded structural diagram of the electromagnetic brake for robot joints provided in an embodiment of the present invention.

[0014] Figure label: 1-Stator coil; 2-Slot plate; 3-Armature; 4-Torque spring; 5-Friction plate; 6-Cover plate; 7-Screw; 31-Stepped bend; 32-Protruding end; 33-Groove end; 34-Step; 35-Mounting groove; 61-Ear; 21-Annular groove. Detailed Implementation

[0015] For ease of understanding, the electromagnetic actuator for robot joints provided in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0016] This invention provides an electromagnetic actuator for robot joints, such as... Figure 1 and Figure 2 As shown, it includes: armature 3, which has a stepped bend 31, and the protruding end 32 of the stepped bend 31 is built into the inner hole of the stator and forms a positioning guide. The groove end 33 of the stepped bend 31 is provided with a friction plate 5 and a cover plate 6, and the friction plate 5 and the cover plate 6 are built into the interior of the stator. A stator coil 1 is provided on the outer edge of the step 34 of the stepped bend 31, and a torque spring 4 is provided between the stator coil 1 and the armature 3.

[0017] Compared with the prior art, the electromagnetic actuator for robot joints described in this embodiment of the invention has the following advantages: In the electromagnetic brake for robot joints provided in this embodiment of the invention, the armature 3 has a stepped bend 31, and the protruding end 32 of the stepped bend 31 is built into the inner hole of the stator to form a positioning guide. A friction plate 5 and a cover plate 6 are placed at the grooved end 33 of the stepped bend 31. Since the friction plate 5 and the cover plate 6 are built into the interior of the stator, the structure can be simplified without sacrificing the magnetic circuit or stator strength, and the overall axial thickness of the machine can be effectively reduced. Because a stator coil 1 is provided on the outer edge of the step 34 of the stepped bend 31, and a torque spring 4 is provided between the stator coil 1 and the armature 3, the stator... When the sub-coil 1 is energized, it can attract the armature 3 to move together and release the axial movement space of the friction plate 5. When the stator coil 1 is de-energized, the electromagnetic field gradually disappears, and the torque spring 4 can push out the armature 3 and press the friction plate 5. Thus, the bending height of the armature 3 determines the working gap of the friction plate 5. At the same time, the size of the concave part is embedded in the thickness space of the friction plate 5 and the cover plate 6, thereby effectively compressing the thickness of the two parts. In other words, in this application, the friction plate 5 is placed in the groove space of the armature 3. During operation, the whole movement releases and presses, so that the electromagnetic brake structure can be as thin as 7mm without sacrificing the magnetic circuit or stator strength.

[0018] It should be noted that in the prior art, thin brakes have a stator slot, but the stator slot will significantly weaken the magnetic circuit and strength and reduce the braking torque; while the technical solution of this application avoids the stator slot, so the magnetic circuit is more complete and thinner. That is, this application can simplify the structure and effectively reduce the axial thickness of the whole machine without sacrificing the magnetic circuit or stator strength. In addition, the bending structure of the armature in this application must simultaneously meet the following requirements: (1) the protruding end of the stepped bending part is built into the inner hole of the stator and forms a positioning guide part; (2) the groove end of the stepped bending part is provided with a friction plate and a cover plate; (3) the friction plate and the cover plate are built into the interior of the stator. Therefore, this application can simplify the structure without sacrificing the magnetic circuit or the strength of the stator, and effectively reduce the axial thickness of the whole machine. Furthermore, in this application, the friction plate and the cover plate are together wrapped within the stepped bend of the armature and simultaneously built into the interior of the stator, thus achieving structural nesting and space reuse. This simplifies the structure without sacrificing the magnetic circuit or stator strength and effectively reduces the overall axial thickness.

[0019] Among them, such as Figure 1 and Figure 2 As shown, the armature 3 and its stepped bending portion 31 can preferably be integrally bent by stamping, thereby enabling precise control of the part size while omitting the bushing part.

[0020] In practical applications, such as Figure 1 and Figure 2 As shown, the robot joint electromagnetic brake provided in this embodiment of the invention may further include: a slot 2, a cover plate 6 which can be assembled with the slot 2 by screws 7, and a friction plate 5, an armature 3, a torque spring 4, and a stator coil 1 which are assembled between the cover plate 6 and the slot 2.

[0021] The working principle and action relationship of the electromagnetic brake for robot joints provided in this embodiment of the invention are as follows: After the stator coil 1 is connected to the DC24V power supply, it generates a magnetomotive force, which generates an electromagnetic force through the slot 2 and armature 3 circuit, and attracts the armature 3 to move towards the slot 2 to compress the torque spring 4. At this time, the friction plate 5 is released and can rotate freely; when the power is off, the electromagnetic force decreases, the torque spring 4 pushes out to clamp the friction plate 5 and generates friction torque to maintain braking.

[0022] Among them, such as Figure 1 and Figure 2As shown, the cover plate 6 can have three ears 61 evenly distributed along the circumference, and the ears 61 can be used to pass through the screws 7; the body of the armature 3 can have three mounting slots 35 evenly distributed along the circumference, and the three ears 61 are placed in the three mounting slots 35 one by one, so as to achieve good assembly of the cover plate 6 with the slot plate 2 by the screws 7, and the friction plate 5, armature 3, torque spring 4, and stator coil 1 are assembled between the cover plate 6 and the slot plate 2.

[0023] Specifically, such as Figure 1 and Figure 2 As shown, the aforementioned slot 2 may have an annular slot 21, and the annular slot 21 can be used to place the stator coil 1.

[0024] Furthermore, such as Figure 1 and Figure 2 As shown, the aforementioned torque spring 4 may include six, and the six torque springs 4 may preferably be evenly distributed along the circumference of the stator coil 1.

[0025] In summary, the electromagnetic actuator for robot joints provided in this embodiment of the invention has the following advantages: First, auxiliary components such as the equal-height bushing in the traditional structure have been eliminated (the equal-height bushing, as an independent component, not only increases the number of parts and assembly steps, but also occupies internal space and limits further thickness compression). By bending the armature, precise matching between the armature and the stator coil and stator is directly achieved. Furthermore, the armature adopts an internal stacking layout, making full use of internal space and compressing the overall thickness of the brake to 7mm, which can meet the ultra-thin installation requirements of humanoid robot joints. At the same time, the armature bending structure also serves as a positioning and guiding component, thereby effectively improving the stability and response speed of the armature movement. In other words, this application integrates positioning and guiding functions into the armature body by bending the armature, and completely eliminates the equal-height bushing by controlling the bending size; the bent edge directly cooperates with the stator to achieve precise positioning, while maximizing the utilization of internal space, ensuring sufficient geomagnetic circuit and friction area even with a thickness of 7mm; that is, in the prior art, the equal-height column occupies about 15% of the internal space, making it difficult to further reduce the overall thickness of the brake, and resulting in a large number of parts and a large weight; while this application improves the internal space utilization by 20% after eliminating the equal-height column bushing, achieving a braking torque comparable to that of traditional brakes with a thickness of 7mm; at the same time, the number of parts is reduced by 30% and the overall weight is reduced by 25%, thereby effectively reducing joint load and improving robot motion performance; Second, the number of parts is significantly reduced. After eliminating the equal-height columns in the traditional structure, the assembly process is simplified from multi-step positioning to single-step nested assembly. In addition, the bending armature has a built-in positioning function, which effectively reduces the dependence on machining accuracy and improves the yield and production efficiency. At the same time, the modular design facilitates later maintenance and replacement, thereby effectively reducing the cost of use. In other words, compared to the prior art where the screw passes sequentially through the armature, stator, and three equal-height bushings before being locked onto the cover plate (which is relatively thin and has a short effective thread length), the short effective engagement of the screw makes it prone to loosening. Furthermore, the screw thread connection can only be achieved by applying liquid thread filler to the screw tip, which can easily lead to thread sealant buildup and jamming. In contrast, in this application, the screw is locked onto the stator, resulting in a more reliable connection and superior assembly reliability. That is, in the prior art, the spring must be installed first, then the armature is pre-pressed onto the stator to hold the spring in place, and then the assembly is reversed. Installing three equal-height bushings, friction plates, and cover plates, aligning them with the screw holes, reversing the assembly, inserting the screws, and tightening the screws—each step requires high-precision positioning, making the process complex and demanding high levels of worker skill and equipment precision. In contrast, this application employs a single-step nested assembly method. After the coil is embedded in the stator slot, the bent armature can be directly nested in the stator's central hole for positioning, ensuring coaxiality and motion stability without the need for additional positioning components. This reduces assembly steps by more than 60%, significantly improving production efficiency while reducing reliance on machining precision, and increasing the yield rate to over 99%. Third, while compressing the thickness to 7mm, it maintains braking torque and response speed comparable to traditional brakes; moreover, the built-in stacking structure effectively reduces the overall weight of the brake, reduces joint load, and improves robot motion performance; at the same time, the structure is compact, has strong anti-interference ability, and is suitable for joint drive of humanoid robots in complex working conditions. In other words, the working principle of the brake in this application is such that the electromagnetic force only needs to drive the single part of the bent armature to move after being energized, so the action response is fast and the action is flexible; while in the prior art, the action is achieved by driving the armature and three equal-height bushings and screw-connected cover plates to move as a whole. The entire system component is moved, and the low connection accuracy of the components is prone to quality risks such as jamming. Moreover, the movement of the entire component requires a larger electromagnetic force, and the response time is naturally longer than that of this application. Fourth, in the prior art, the height column is an independent component, which is subject to the risk of fatigue failure and assembly error. Moreover, maintenance requires disassembling the entire brake and replacing the height bushing is costly. In contrast, the bent armature in this application is an integrated structure, which eliminates the risk of height column failure. Furthermore, the modular design facilitates later maintenance and replacement. Maintenance only requires replacing the friction plate or armature, without disassembling the stator and coil, reducing maintenance costs by more than 50%. This also reduces structural redundancy and effectively lowers maintenance costs. Fifth, the bottom of the brake structure can better reserve customer installation interfaces or integrate bearings for a better deceleration layout; in contrast, the built-in cover plate in the existing technology needs to move as an integral part of the armature, which must be avoided in the structural design.

[0026] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An electromagnetic brake for robot joints, characterized in that, include: The armature has a stepped bend, and the protruding end of the stepped bend is built into the inner hole of the stator to form a positioning guide. The groove end of the stepped bend is provided with a friction plate and a cover plate, and the friction plate and the cover plate are built into the interior of the stator. A stator coil is provided on the outer edge of the stepped bend, and a torque spring is provided between the stator coil and the armature.

2. The electromagnetic actuator for robot joints according to claim 1, characterized in that, The armature and the stepped bending portion are integrally bent by stamping.

3. The electromagnetic actuator for robot joints according to claim 1, characterized in that, Also includes: The cover plate is assembled to the slotted plate by screws, and the friction plate, the armature, the torque spring, and the stator coil are assembled between the cover plate and the slotted plate.

4. The electromagnetic actuator for robot joints according to claim 3, characterized in that, The cover plate has three ears that are equidistantly distributed along the circumference, and the ears are used to pass through the screw; the armature body has three mounting slots that are equidistantly distributed along the circumference, and the three ears are placed in the three mounting slots one by one.

5. The electromagnetic actuator for robot joints according to claim 4, characterized in that, The slot has an annular groove, and the annular groove is used to place the stator coil.

6. The electromagnetic actuator for robot joints according to claim 5, characterized in that, The torque springs comprise six springs, and the six torque springs are evenly distributed along the circumference of the stator coil.

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