A multi-contact motor forward and reverse control device

By adopting the successively-on design and the coordination of electromagnetic components in the motor forward and reverse control device, the problems of arc erosion, contact welding and insufficient response speed are solved, and higher reliability, safety and service life are achieved.

CN119517691BActive Publication Date: 2025-04-15SHANXI TAIRUI ELECTRICAL AUTOMATION EQUIPMENT CO LTD
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Patent Information

Application Number
CN202510058423.7
Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Filing Date
2025-01-15
Publication Date
2025-04-15
Estimated Expiration
2045-01-15

AI Technical Summary

Technical Problem

There are problems such as arc erosion, contact welding, single contact wear and return spring failure in existing motor forward and reverse control devices, resulting in short service life, high maintenance costs and insufficient response speed.

Method used

A multi-contact motor forward and reverse control device is designed, adopting a sequentially connected design, through the sequential connection between the dynamic contact and the fixed contact, dispersing the current load, reducing arc erosion and wear of a single contact, and ensuring rapid response and safe disconnection through the coordination of electromagnetic components and return springs.

Benefits of technology

Effectively reduce the risks of arc erosion and contact welding, extend the service life of the device, reduce maintenance costs, and improve response speed and system safety.

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Abstract

The present invention provides a multi-contact motor forward and reverse control device, the structure of which includes a rotatable moving contact, an elastic telescopic rod, a sliding push rod and an electromagnetic assembly. The electromagnetic assembly serves as a driving force to achieve rapid switching of the moving contact position to control the forward and reverse rotation of the motor. The moving contact is designed to be connected with the fixed contact in succession; the sliding push rod cooperates with the reciprocating booster block on the back of the moving contact to achieve rapid and smooth movement of the moving contact. The device adopts a miniaturized design, has a compact structure, saves space, and is easy to install and integrate into various electrical control systems. In addition, the scraping effect of the moving contact during the connection process automatically cleans the fixed contact, effectively prevents contact welding, and enhances the safety of the system. The maintenance cost is low, the device is easy to disassemble and maintain, and can ensure safe disconnection even in the event of a reset spring failure, and is suitable for a wide range of industrial automation applications.
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Description

Technical Field

[0001] The invention belongs to a motor forward and reverse reversing control device, in particular to a multi-contact motor forward and reverse reversing control device. Background Art

[0002] The forward and reverse control of the motor is a key function in industrial automation and electrical control systems. Traditionally, this function is usually achieved by AC contactors, which control the power connection of the motor by closing and opening contacts. However, there are some problems that need to be solved in the AC contactors in the prior art.

[0003] The arc erosion problem is one of the main defects in the prior art. As described in patent CN103699024B, even in a relay system, the contacts may be eroded by arcs when they are disconnected, which accelerates the wear of the contacts and shortens the service life of the contactor. In addition, patent CN201927550U discloses a reversing contactor, but there is also the problem that the contacts may be eroded by arcs during the opening and closing process.

[0004] The risk of contact welding is another key issue. In the reversing contactor mentioned in the CN201927550U patent, if there are impurities or foreign matter between the contacts, or the current is too large, the contacts may weld together, causing the contactor to fail to work properly, increasing the risk of safety accidents.

[0005] The problem of single contact wear is particularly evident in certain designs, where only one or a few contacts may be involved in making and breaking the circuit, causing these contacts to experience greater wear, thereby increasing maintenance costs and failure rates.

[0006] The failure of the reset spring will also affect the normal operation of the contactor. If the reset spring fails, it may cause the contactor to fail to disconnect properly, affecting safety.

[0007] In addition, due to problems such as arc erosion and contact welding, it may be necessary to frequently replace contacts or the entire contactor, increasing maintenance costs. At the same time, some contactor designs may not respond fast enough to meet the needs of fast switching.

[0008] The information disclosed in the background technology section of this application is only intended to deepen the understanding of the general background technology of this application, and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. Summary of the invention

[0009] In response to these problems in the prior art, the present invention aims to provide a multi-contact motor forward and reverse control device to solve the arc erosion problem, thereby improving the reliability and safety of motor control, reducing maintenance costs, and increasing response speed.

[0010] The above purpose is achieved through the following technical solutions:

[0011] Provided is a multi-contact motor forward and reverse control device, comprising: a housing component, in which two sets of opposite fixed contacts are fixedly installed, and a conducting component is correspondingly arranged between the two sets of fixed contacts;

[0012] A conducting component, comprising a moving contact, an elastic telescopic rod, a sliding push rod and a tension spring;

[0013] The moving contact corresponds to the fixed contact and is rotatably connected to one end of the elastic telescopic rod, and the other end of the elastic telescopic rod is vertically fixed to the side of the assembly plate; the assembly plate is slidably installed in the housing assembly;

[0014] The side surface of the assembly plate is slidably connected to one end of a sliding push rod, the other end of the sliding push rod is against the back of the moving contact, and the sliding direction of the sliding push rod is parallel to the rotation axis of the moving contact.

[0015] In one embodiment, a first reciprocating booster block and a second reciprocating booster block are staggered along the rotation axis of the moving contact on the back side thereof, a first magnet is fixedly mounted on one side of the first reciprocating booster block, and a second magnet is fixedly mounted on one side of the second reciprocating booster block.

[0016] In one embodiment, a first guide groove and a second guide groove are provided on the back of the moving contact, the first guide groove and the second guide groove are parallel to the sliding direction of the sliding push rod, and are connected to the first reciprocating boosting block and the second reciprocating boosting block;

[0017] The first guide groove and the second guide groove are one-way slideways in opposite directions. The first magnet is arranged at one end of the first guide groove and the second magnet is arranged at one end of the second guide groove.

[0018] In one of the embodiments, the assembly plate is vertically mounted in the middle of the connecting rod, and two sliding blocks are fixedly connected to both ends of the connecting rod respectively, and the sliding blocks are slidably connected to the housing assembly.

[0019] In one of the embodiments, electromagnetic components are fixedly mounted on both ends of the shell component, and the conductive component is driven to slide inside the shell component through the adsorption effect of the electromagnetic component.

[0020] In one of the embodiments, a return spring is arranged between the electromagnetic assembly and the sliding block.

[0021] In one embodiment, one end of the elastic telescopic rod is fixedly connected to a tension spring, and the other end of the tension spring is connected to the assembly plate.

[0022] In one of the embodiments, the housing assembly includes a base, an end cover and a middle frame, two bases are fixedly mounted at two ends of the middle frame, and two end covers are fixedly mounted at the ends of the two bases, respectively.

[0023] In one of the embodiments, a wiring port is provided outside the base, and the wiring port corresponds to a fixed contact in the connection end cover.

[0024] In one embodiment, the output directions of the two groups of fixed contacts are opposite.

[0025] The beneficial effects of the present invention are as follows: One of the most significant advantages of the multi-contact motor forward and reverse control device of the present invention is the sequential connection function. This design significantly reduces arc erosion and prolongs the service life of the contactor. In the sequential connection process, the moving contact and the fixed contact are not in contact at the same time, but are connected in sequence, which can avoid the current from concentrating on a single contact, thereby dispersing the current load and reducing the wear of a single contact.

[0026] In addition, the sequential connection also has a cleaning function. When the moving contact contacts the fixed contact, it will scrape off the impurities on it, keeping the contact surface clean, ensuring good electrical connection, effectively preventing the risk of contact welding, and further enhancing the safety and reliability of the device. The use of electromagnetic components enables the device to quickly respond to the control requirements of the motor's forward and reverse rotation, providing fast switching capabilities. This fast response not only improves the efficiency of the system, but also meets the needs of fast switching in industrial automation. Even if the reset spring fails, the device can still ensure the disconnection of the contacts, which enhances the overall safety and reduces the risk of safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 , schematic diagram of the overall structure of the multi-contact motor forward and reverse control device;

[0028] Figure 2 , the overall exploded view of the multi-contact motor forward and reverse control device;

[0029] Figure 3 , a schematic diagram of the three-dimensional structure of the conducting component;

[0030] Figure 4 , the main view of the conductive component structure;

[0031] Figure 5 , Figure 4 AA section view;

[0032] Figure 6 , Figure 5 A magnified view of the structure of part B;

[0033] Figure 7 , overall schematic diagram of moving contact;

[0034] Figure 8 , the overall side view of the multi-contact motor forward and reverse control device;

[0035] Fig. 9 , Figure 8 CC section view;

[0036] Fig.10 , Fig. 9 A magnified structural diagram of part D;

[0037] Fig.11 , circuit control diagram of multi-contact motor forward and reverse control device.

[0038] Numbers in the figure: 100, housing assembly; 110, fixed contact; 111, wiring port; 120, end cover; 130, base; 140, middle frame; 160, reset spring; 200, conduction assembly; 210, moving contact; 211, electrode sheet; 212, first reciprocating booster block; 213, second reciprocating booster block; 214, first magnet; 215, second magnet; 216, first guide groove; 217, second guide groove; 220, assembly plate; 221, connecting rod; 222, sliding block; 230, elastic telescopic rod; 231, tension spring; 240, sliding push rod; 300, electromagnetic assembly. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0040] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0041] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0042] The multi-contact motor forward and reverse control device of the present invention is as follows Figures 1 to 10 As shown, the device is mainly composed of a housing component 100, a conducting component 200, an electromagnetic component 300 and other structures.

[0043] like Figure 1 As shown, the housing assembly 100 is composed of a base 130, an end cover 120 and a middle frame 140. The two bases 130 are fixedly mounted at both ends of the middle frame 140, and the end covers 120 are respectively fixed at the ends of the bases 130 to form the overall structure of the housing assembly. The housing assembly 100 is used to locate and install the internal structure, protect the interior, and facilitate disassembly and maintenance.

[0044] The base 130 is provided with a wiring port 111 outside, and the wiring port 111 corresponds to the fixed contact 110 in the connection end cover 120 to ensure the input and output of the motor control signal.

[0045] The conducting assembly 200 is the core component for realizing the forward and reverse control of the motor, and includes a moving contact 210, an assembly plate 220, an elastic telescopic rod 230 and a sliding push rod 240. The moving contact 210 corresponds to the fixed contact 110, and there are two groups of moving contacts 210, and the structures of the two groups of moving contacts 210 are symmetrical to each other. The side of the moving contact 210 facing the fixed contact 110 is the front side, which is used to connect the corresponding fixed contact 110 and is provided with an electrode sheet 211. The moving contact 210 is tilted when it is not in contact with the fixed contact 110. In the process of approaching the fixed contact 110, the moving contact 210 rotates, successively connects the fixed contacts, and at the same time scrapes off the impurities on the fixed contact 110.

[0046] The movable contact 210 is connected to the end of the elastic telescopic rod 230 through a rotating shaft perpendicular to the telescopic direction of the elastic telescopic rod 230. The other end of the elastic telescopic rod 230 is fixed to the side of the assembly plate 220. A tension spring 231 is fixedly connected to one end of the elastic telescopic rod 230, and the other end of the tension spring 231 is connected to the assembly plate 220. The function of the tension spring 231 is to provide a restoring force when the movable contact 210 is away from the fixed contact 110, so as to ensure that the movable contact 210 can quickly return to the initial position.

[0047] The assembly plate 220 is slidably installed in the housing assembly 100, and can drive the movable contact 210 to move up and down on the assembly plate 220 to achieve contact or separation with the fixed contact 110, thereby achieving forward control and reverse control.

[0048] The side of the assembly plate 220 is slidably connected to one end of the sliding push rod 240 through a surface groove, and the sliding direction is parallel to the rotation axis of the moving contact 210. The other end of the sliding push rod 240 is against the back of the moving contact 210. The back of the moving contact 210 is provided with two dislocated protrusion-shaped first reciprocating booster blocks 212 and second reciprocating booster blocks 213 along the direction of its rotation axis, which are used to cooperate with the sliding push rod 240. The sliding push rod 240 is rotated to make the relative movement on the protrusion of the first reciprocating booster block 212 or the second reciprocating booster block 213, which helps push the contact 210, and then drives the elastic telescopic rod 230 to extend, and the tension spring 231 accumulates force. After the moving contact 210 moves away from the fixed contact 110, the tension spring 231 releases energy to return the angle of the moving contact 210 to the initial state of inclination. This structure can also play the role of disconnecting the contact when the power is suddenly cut off.

[0049] The back of the moving contact 210 is also provided with a first guide groove 216 and a second guide groove 217, which are parallel to the rotation axis of the moving contact 210, and are located on both sides of the first reciprocating booster block 212 and the second reciprocating booster block 213 and connected thereto; the first guide groove 216 and the second guide groove 217 ensure the stable movement of the sliding push rod 240. A first magnet 214 is fixedly installed at one end of the first guide groove 216, and a second magnet 215 is fixedly installed at one end of the second guide groove 217. The magnets can absorb the sliding push rod 240 sliding into the guide groove, forming a one-way slideway of the sliding push rod 240. The sliding directions of the sliding push rod 240 in the first guide groove 216 and the second guide groove 217 are opposite, and the reciprocating movement steps are automatically realized in combination with the relative movement of the sliding push rod 240 and the first reciprocating booster block 212 and the second reciprocating booster block 213.

[0050] In this embodiment, the scheme for realizing the sliding of the conduction component 200 in the housing component 100 is as follows: the sliding assembly plate 220 is vertically mounted in the middle of the connecting rod 221, and two sliding blocks 222 are fixedly connected at both ends of the connecting rod 221. The sliding blocks 222 are slidably connected to the base 130, allowing the assembly plate 220 to move linearly in the housing component 100. The drive adopts two sets of electromagnetic components 300, which are respectively fixedly mounted on the end caps 120 at both ends of the housing component 100. The suction force generated by the electromagnetic components drives the conduction component 200 to slide in the housing component 100, so that the moving contact 210 can realize forward and reverse control under the action of the electromagnetic components 300.

[0051] A return spring 160 is provided between the electromagnetic assembly 300 and the sliding block 222 . When the electromagnetic assembly is powered off, the return spring 160 can return the sliding block 222 and the moving contact 210 to an initial state.

[0052] The circuit control of the present invention is as follows Fig.11 As shown, the outputs of the upper and lower groups of fixed contacts 110 are opposite, the upper group is a reverse output to control the motor to reverse, and the lower group is a forward output to control the motor to rotate forward.

[0053] The working principle of the multi-contact motor forward and reverse control device of the present invention is to realize the forward and reverse control of the motor through the interaction between the mechanical structure and the electromagnetic component. The following is a detailed description of the working principle of the device:

[0054] 1. Initial state:

[0055] When the device is in an initial state, the conducting component 200 is located in the middle of the housing component 100 .

[0056] At this time, the movable contact 210 does not contact the fixed contact 110, and is in an inclined state, with the lower movable contact 210 being higher on the left and lower on the right. Figure 7 As shown, the sliding push rod 240 is located in the first guide groove 216 due to the initial tension of the tension spring 231 .

[0057] 2. Forward control:

[0058] The electromagnetic assembly 300 below is energized to generate suction force, attracting the sliding block 222 to move downward.

[0059] The sliding block 222 drives the assembly plate 220 and the moving contact 210 to move downward through the connecting rod 221. The moving contact 210 on the lower side of the assembly plate 220 moves downward until one end contacts the fixed contact 110. As it slides downward, the moving contact 210 rotates until it is horizontal, and is connected with the fixed contact 110 successively. During the process, the electrode sheet 211 on the surface of the moving contact 210 scrapes off impurities on the fixed contact 110, cleans the contact surface, and ensures a good electrical connection.

[0060] The present invention utilizes rotation to make the sliding push rod 240 cooperate with the reciprocating boosting block.

[0061] During the forward connection process, as the moving contact 210 rotates, the sliding push rod 240 moves relatively from the first guide groove 216 along the first reciprocating boosting block 212. When the moving contact 210 is horizontal, the sliding push rod 240 passes over the most convex point of the first reciprocating boosting block 212, reaching the state as shown in FIG. Fig.10 Position shown.

[0062] When disconnected, the moving contact 210 is separated from the fixed contact 110, and the tension spring 231 provides tension, so that the sliding push rod 240 continues to slide relatively along the first reciprocating boosting block 212, and the sliding push rod 240 falls into the second guide groove 217, and under the attraction of the second magnet 215, the sliding push rod 240 slides toward the second reciprocating boosting block 213. When the next forward rotation is connected, the sliding push rod 240 slides relatively along the second reciprocating boosting block 213 to achieve reciprocating cooperation.

[0063] 3. Inversion control:

[0064] The upper electromagnetic assembly 300 is energized and moves upward with the attraction sliding block 222. The moving contact 210 on the upper side of the assembly plate 220 is successively connected with the upper fixed contact 110, and the process is analogous to the action of each structure in a forward connection.

[0065] 4. Function of the return spring 160:

[0066] After the electromagnetic assembly 300 is powered off, the return spring 160 pushes the sliding block 222 to slide, thereby returning the moving contact 210 to the initial state, in preparation for the next forward and reverse rotation control.

[0067] 5. Power failure disconnection control:

[0068] The tension spring 231 stores force when the movable contact 210 contacts the fixed contact 110, and provides a restoring force when a power outage occurs, so that the movable contact 210 rotates to disconnect from the fixed contact 110, thereby enhancing the safety of the device.

[0069] The multi-contact motor forward and reverse rotation control device of the present invention realizes the forward and reverse rotation control of the motor through a series of precisely designed mechanical structures and electromagnetic components.

[0070] The multi-contact motor forward and reverse control device of the present invention not only realizes the precise control of the motor's forward and reverse rotation, but also has the function of successively connecting fixed contacts and cleaning contacts, thereby effectively preventing arc erosion and improving safety, thereby significantly improving the performance and reliability of the motor control device.

[0071] The beneficial effect of this embodiment is that the successive connection of the moving contacts 210 reduces the number of times the contacts are eroded by arcs, thereby extending the service life of the AC contactor. At the same time, the scraping action of the moving contacts 210 on the contact surface prevents the generation of debris between the contacts, thereby avoiding the problems of arcs and contact welding. In addition, even if the reset spring fails, the device can still ensure the disconnection of the contacts, thereby enhancing the overall safety.

[0072] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The above-described embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A multi-contact motor forward and reverse control device, characterized in that: include: A housing component (100), wherein two sets of opposite fixed contacts (110) are fixedly mounted in the housing component (100), and a conduction component (200) is correspondingly arranged between the two sets of fixed contacts (110); A conduction assembly (200) comprising a moving contact (210), an elastic telescopic rod (230), a sliding push rod (240) and a tension spring (231); The movable contact (210) corresponds to the fixed contact (110) and is rotatably connected to one end of the elastic telescopic rod (230), and the other end of the elastic telescopic rod (230) is vertically fixed to the side of the assembly plate (220); the assembly plate (220) is slidably installed in the housing assembly (100); the side of the movable contact (210) facing the fixed contact (110) is the front side, which is used to connect the corresponding fixed contact (110) and is provided with an electrode sheet (211); the movable contact (210) is tilted when not in contact with the fixed contact (110); The side surface of the assembly plate (220) is slidably connected to one end of a sliding push rod (240), the other end of the sliding push rod (240) is against the back of the moving contact (210), and the sliding direction of the sliding push rod (240) is parallel to the rotation axis of the moving contact (210); A first reciprocating boosting block (212) and a second reciprocating boosting block (213) are provided on the back side of the moving contact (210) along the direction of its rotation axis. The sliding push rod (240) is caused to move relatively on the protrusion of the first reciprocating boosting block (212) or the second reciprocating boosting block (213) by rotation, thereby boosting the moving contact (210), thereby driving the elastic telescopic rod (230) to extend, and the tension spring (231) to store force. After the moving contact (210) moves away from the fixed contact (110), the tension spring (231) releases energy to return the angle of the moving contact (210) to the initial state of inclination. A first magnet (214) is fixedly mounted on one side of the first reciprocating boosting block (212), and a second magnet (215) is fixedly mounted on one side of the second reciprocating boosting block (213). A first guide groove (216) and a second guide groove (217) are formed on the back of the moving contact (210). The first guide groove (216) and the second guide groove (217) are parallel to the sliding direction of the sliding push rod (240), and are connected to the first reciprocating boosting block (212) and the second reciprocating boosting block (213); The first guide groove (216) and the second guide groove (217) are one-way slideways with opposite directions. The first magnet (214) is arranged at one end of the first guide groove (216), and the second magnet (215) is arranged at one end of the second guide groove (217). The magnets can absorb the sliding push rod (240) that slides into the guide groove, thereby forming a one-way slideway for the sliding push rod (240). The sliding directions of the sliding push rod (240) in the first guide groove (216) and the second guide groove (217) are opposite.

2. The multi-contact motor forward and reverse control device according to claim 1, characterized in that: The assembly plate (220) is vertically mounted in the middle of the connecting rod (221), and two ends of the connecting rod (221) are respectively fixedly connected to two sliding blocks (222), and the sliding blocks (222) are slidably connected to the housing assembly (100).

3. The multi-contact motor forward and reverse control device according to claim 1, characterized in that: Electromagnetic components (300) are fixedly mounted on both ends of the housing component (100), and the conductive component (200) is driven to slide inside the housing component (100) through the adsorption effect of the electromagnetic component (300).

4. The multi-contact motor forward and reverse control device according to claim 3, characterized in that: A return spring (160) is provided between the electromagnetic assembly (300) and the sliding block (222).

5. The multi-contact motor forward and reverse control device according to claim 1, characterized in that: One end of the elastic telescopic rod (230) is fixedly connected to a tension spring (231), and the other end of the tension spring (231) is connected to the assembly plate (220).

6. The multi-contact motor forward and reverse control device according to any one of claims 1 to 5, characterized in that: The housing assembly (100) comprises a base (130), an end cover (120) and a middle frame (140), wherein the two bases (130) are fixedly mounted at two ends of the middle frame (140), and the two end covers (120) are respectively fixedly mounted at the ends of the two bases (130).

7. The multi-contact motor forward and reverse control device according to claim 6, characterized in that: The base (130) is provided with a wiring port (111) outside, and the wiring port (111) corresponds to the fixed contact (110) in the connection end cover (120).

8. The multi-contact motor forward and reverse control device according to claim 7, characterized in that: The two groups of fixed contacts (110) have opposite output directions.

Citation Information

Patent Citations

  • Relay system

    CN103699024B

  • Reversing contactor

    CN201927550U

  • Sliding type contact self-cleaning relay and contact self-cleaning method

    CN114334549A

  • Electromagnetic switch device

    CN114914125A