Multi-auxiliary loop direct current contactor
By designing a multi-assisted loop structure in a DC contactor, and controlling multiple auxiliary needles with a movable contact, a movable frame and an auxiliary push block, the problem of difficulty in realizing multi-circuit control in the prior art is solved and the stability of the system is achieved Double improvement and cost.
Patent Information
- Application Number
- CN202411519645.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-29
- Publication Date
- 2024-12-31
AI Technical Summary
When existing DC contactors face complex working conditions and high reliability requirements, it is difficult to achieve multi-loop control. Adding independent contactors or using complex relay combinations will lead to increased system size, increased cost, poor stability, and coordinated. The working states of each circuit are difficult and are prone to cause malfunctions or failures.
Design a multi-assisted loop DC contactor, using the moving contacts in the ceramic cover to cooperate with the static contacts, and control multiple auxiliary needles through the movable frame and auxiliary push block, and use micro switches and metal connecting plates to realize multi-circuit control, simplify structure and improve reliability.
It realizes effective control of multiple loops by a single contactor, reduces system complexity and cost, improves system stability and service life, and reduces structural complexity and risk of misoperation.
Smart Images
Figure CN119230342A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of a DC contactor, and in particular to a multi-auxiliary circuit DC contactor. Background Art
[0002] A DC contactor is a contactor whose core is controlled by a DC coil. Its load can be either DC or AC. Since the attraction coil of the DC contactor is connected to DC, there is no impact starting current and no violent impact of the core. Therefore, it has a long life and is suitable for occasions with frequent start and stop. Although the DC contactor is relatively mature, it still has certain limitations when facing complex working conditions and high reliability requirements. For example, the DC contactor has only one set of main contact circuits and one set of auxiliary circuits, which cannot meet the needs of multi-circuit control.
[0003] In order to achieve multi-loop control in the related art, multiple independent contactors are added or complex relay combinations are used. These methods can solve the problem to a certain extent, but adding multiple independent contactors will increase the system size, increase costs, and make installation and maintenance inconvenient. Although multi-loop control can be achieved when using a complex relay combination, the stability of the overall system is poor due to the reliability and life limitations of the relay itself. In addition, these methods also have great difficulties in coordinating the working status of each loop, which can easily cause malfunctions or failures. Summary of the invention
[0004] In order to provide multi-circuit control using a single contactor, the present application provides a multi-auxiliary circuit DC contactor.
[0005] The present application provides a multi-auxiliary circuit DC contactor, which adopts the following technical solution: A multi-auxiliary circuit DC contactor comprises a shell, at least two static contacts extending into the shell are arranged on the shell, a ceramic cover is arranged in the shell, the static contacts are inserted into the interior of the ceramic cover, a moving contact is arranged in the ceramic cover, the moving contact is connected to a transmission component, the transmission component comprises a movable frame, the moving contact is connected to the movable frame, and the movable frame drives the moving contact to move in the same direction when moving, at least one group of auxiliary lead pins is arranged on the ceramic cover, and a group of auxiliary lead pins is provided with three, one end of the auxiliary lead pin is outside the ceramic cover and connected to a circuit connection plate, the circuit connection plate is connected to leads extending out of the shell, each lead is electrically connected to an auxiliary lead pin, an auxiliary push block is arranged on the movable frame, and the auxiliary push block is used to control the on-off of the three auxiliary lead pins.
[0006] By adopting the above technical solution, when in use, the moving contact moves toward the static contact under the action of the movable frame, and at the same time the auxiliary push block on the movable frame moves toward the direction of the auxiliary lead pin. When the moving contact contacts the static contact, the auxiliary push block will control the connection status of the three auxiliary lead pins, so that when multiple circuits need to be controlled, the three auxiliary lead pins can be controlled at the same time, so that a single contactor can be used to control multiple circuits.
[0007] Preferably, a column is fixedly arranged inside the ceramic cover, and the column is arranged corresponding to a group of auxiliary pins. A micro switch is fixedly arranged on the column, and the three pins of the micro switch correspond one by one to the three auxiliary pins in a group respectively. The micro switch is opened or closed by an auxiliary push block.
[0008] By adopting the above technical solution, the three pins of the micro switch can be normally open or normally closed, so that the three auxiliary pins are respectively connected to the three pins. When the micro switch is pushed open or closed by the auxiliary push block, the corresponding control circuit can be controlled.
[0009] Preferably, a plurality of metal connecting plates are fixedly provided on the column, one side of the metal connecting plate is electrically connected to the pin of the micro switch, and the other side is used to abut against the side wall of the auxiliary lead pin.
[0010] By adopting the above technical solution, the metal connecting piece is fixed on the column and electrically connected to the micro switch. Then, when the auxiliary lead pin is installed on the ceramic cover, the auxiliary lead pin is directly inserted and abuts against the metal connection, so that the auxiliary lead pin is electrically connected to the metal connecting piece, which facilitates the installation of the auxiliary lead pin and the metal connecting piece.
[0011] Preferably, a column is provided in the ceramic cover, a slide is provided on the column, a metal connecting piece is provided in each slide, one end of the metal connecting piece is arranged in an elastic hook shape, when the moving contact is separated from the static contact, one of the metal connecting pieces is detached from the corresponding auxiliary lead pin, and the other two metal connecting pieces are in contact with the corresponding auxiliary lead pins and one of the two auxiliary lead pins in contact with the metal connecting piece is provided with a disconnecting part, when the moving contact is connected with the static contact, the disconnecting part is at the same height as the corresponding metal connecting piece and is arranged separately, and the metal connecting piece is fixed on the auxiliary push block.
[0012] By adopting the above technical solution, a slideway is provided on the column, and when the auxiliary push block drives the metal connecting piece to move and the moving contact is separated from the static contact, the metal connecting piece separated from the auxiliary lead pin will approach and contact the corresponding auxiliary lead pin, and the auxiliary lead pin corresponding to the disconnection part will be separated from the auxiliary lead pin, thereby enabling the auxiliary lead pin to be controlled during the contact process between the moving contact and the static contact, and the auxiliary lead pin is directly connected to the metal connecting piece, thereby reducing the complexity of the structure and improving the service life.
[0013] Preferably, one side of the metal connecting piece abuts against the slideway, and the side of the metal connecting piece away from the slideway is used to abut against the auxiliary guide pin.
[0014] By adopting the above technical solution, the metal connecting piece is clamped between the slideway and the auxiliary lead pin, so that the metal connecting piece can maintain good contact with the auxiliary lead pin, thereby improving the contact force of the metal connecting piece on the auxiliary lead pin.
[0015] Preferably, the moving contact is slidably connected to the inside of the movable frame, and a main spring is arranged between the moving contact and the movable frame, one end of the main spring abuts against the moving contact, and the other end abuts against the movable frame, and after the moving contact contacts the static contact, the main spring contracts, and the movable frame and the auxiliary push block continue to move toward the auxiliary guide pin.
[0016] By adopting the above technical solution, the moving contact is slidably connected to the movable frame. When the moving contact contacts the static contact, the movable frame continues to move, so that the auxiliary push block on the movable frame forms a good contact with the auxiliary lead pin.
[0017] Preferably, a lower push rod is connected to the movable frame, a moving magnetic core is fixedly provided on the lower push rod, a coil is provided on the outer side of the moving magnetic core, the coil is fixed to the outer shell, and a reset spring is provided on the lower push rod, and the reset spring is used to push the lower push rod to move in the direction of separation of the moving contact and the static contact.
[0018] By adopting the above technical solution, a moving magnetic core is fixedly arranged on the lower push rod. When the coil is energized, the magnetic force generated by the coil pushes the moving magnetic core to move, so that the moving magnetic core moves the movable frame through the lower push rod. When the coil is disconnected, the force of the reset spring pushes the lower push rod to recover, so that the moving contact is separated from the static contact.
[0019] Preferably, an intermediate sealing plate is provided on a side of the ceramic cover away from the static contact, the intermediate sealing plate seals the ceramic cover, an exhaust pipe is provided on the intermediate sealing plate, and a one-way valve is installed on the exhaust pipe.
[0020] By adopting the above technical solution, the middle sealing plate seals the ceramic cover, reduces the entry of impurities, ensures good switching between the static contact and the moving contact, the exhaust pipe can discharge the gas in the ceramic cover, and the one-way valve can avoid re-inhalation of air with impurities.
[0021] Preferably, two magnets are fixedly provided on the outside of the ceramic cover via a fixing frame, and the two magnets correspond to the abutment positions of the moving contact and the two static contacts respectively.
[0022] By adopting the above technical solution, a magnet is fixedly provided on the outside of the ceramic cover, and the magnet corresponds to the abutment point between the moving contact and the static contact. When the moving contact and the static contact are separated or contacted, the arc formed can be quickly extinguished under the action of the magnet, thereby reducing the occurrence of ablation and improving the service life. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 This is a schematic diagram of the structure inside the housing of Embodiment 1 of the present application; Figure 2 This is a schematic diagram of the structure of the first embodiment of the present application in which the housing is omitted; Figure 3 It is a schematic diagram of the structure inside the ceramic cover in the first embodiment of the present application; Figure 4 is a schematic diagram of the structure of the transmission assembly in Example 1 of the present application; Figure 5 This is a schematic diagram of the installation structure of the micro switch in the first embodiment of the present application; Figure 6 It is a structural schematic diagram of the auxiliary guide needle in Example 2 of the present application.
[0024] Explanation of the accompanying drawings: 1. Shell; 11. Through hole; 12. Cover body; 2. Static contact; 3. Moving contact; 4. Transmission assembly; 41. Movable frame; 42. Lower push rod; 43. Main spring; 44. Auxiliary push block; 5. Coil; 51. Moving magnetic core; 52. Guide sleeve; 53. Reset spring; 6. Ceramic cover; 61. Intermediate sealing plate; 62. Exhaust pipe; 63. One-way valve; 7. Magnet; 71. Fixed frame; 8. Auxiliary lead pin; 81. Circuit connection plate; 82. Lead wire; 83. Post; 831. Slide; 84. Disconnection part; 9. Micro switch; 91. Metal connecting piece; 10. Connection plate. DETAILED DESCRIPTION
[0025] The following is combined with Figure 1-6 This application is described in further detail.
[0026] An embodiment of the present application discloses a multi-auxiliary circuit DC contactor.
[0027] Embodiment 1: This embodiment discloses a multi-auxiliary circuit DC contactor, referring to Figure 1, including a shell 1, the interior of the shell 1 is a hollow structure, two through holes 11 are provided on one surface of the shell 1, a static contact 2 is fixedly arranged in each through hole 11, the static contact 2 is exposed in the part of the shell 1 for connecting the main line, a moving contact 3 is arranged inside the shell 1, the moving contact 3 is connected to the transmission component 4, the transmission component 4 is provided with a coil 5 on the side away from the moving contact 3, the coil 5 generates magnetic force by passing direct current, so that the transmission component 4 and the moving contact 3 move toward the static contact 2, and the two ends of the moving contact 3 are respectively in contact with the two static contacts 2, so that the two static contacts 2 are energized through the moving contact 3. A cover 12 is provided on the side of the shell 1 away from the through hole 11, and the cover 12 is used to cover the transmission component 4 and the coil 5 in the shell 1.
[0028] A ceramic cover 6 is provided inside the housing 1 near the static contact 2, and an intermediate sealing plate 61 is provided on the side of the ceramic cover 6 away from the static contact 2. The intermediate sealing plate 61 separates the coil 5 from the moving contact 3, so that the moving contact 3 is inside the ceramic cover 6. When the moving contact 3 and the static contact 2 are in contact or separated, the arc formed can be inside the ceramic cover 6, reducing the damage that the arc may cause to the coil 5. An exhaust pipe 62 is fixedly provided on the surface of the intermediate sealing plate 61 away from the ceramic cover 6, and a one-way valve 63 is provided at the end of the exhaust pipe 62, which is used to reduce the entry of impurities into the ceramic cover 6 and reduce the increase in air pressure caused by the increase in internal temperature. One end of the two static contacts 2 inserted into the housing 1 is simultaneously inserted into the ceramic cover 6, so that the connection or separation of the static contact 2 and the moving contact 3 is inside the ceramic cover 6.
[0029] refer to Figure 1 and Figure 2 Two magnets 7 are fixedly arranged on the outside of the ceramic cover 6. The positions of the two magnets 7 on the ceramic cover 6 should be close to the ends of the two static contacts 2. When an arc is generated between the moving contact 3 and the static contact 2, the magnetic force of the magnet 7 is used to generate a force on the arc, so that the arc is stretched in time and extinguished, and the electrical connection between the static contact 2 and the moving contact 3 is quickly disconnected. A U-shaped fixing frame 71 is arranged on the outside of the magnet 7, and the U-shaped opening of the fixing frame 71 faces the ceramic cover 6. The magnet 7 is arranged at the bottom of the U-shaped fixing frame 71, and then the fixing frame 71 is buckled on the ceramic cover 6 from the opening position to fix the magnet 7 on the ceramic cover 6.
[0030] Two groups of auxiliary lead pins 8 are also fixedly arranged on the ceramic cover 6. The auxiliary lead pins 8 are located on the side wall of the ceramic cover 6 through which the static contact 2 is penetrated, and one end of the auxiliary lead pin 8 is located outside the ceramic cover 6, and the other end is located inside the ceramic cover 6. A circuit connection board 81 is fixedly arranged outside the ceramic cover 6. There are three auxiliary lead pins 8 in each of the two groups. Among the three auxiliary lead pins 8 in one group, one is a COM terminal, which is grounded, one is connected to the COM terminal in a normally closed manner, and the other is connected to the COM terminal in a normally open manner. The ends of the two groups of auxiliary lead pins 8 outside the ceramic cover 6 are electrically connected to the circuit connection board 81, and a lead 82 is arranged on the circuit connection board 81. One lead 82 is electrically connected to one auxiliary lead pin 8, so that the lead 82 can extend to the outside of the housing 1 and connect the circuit. The extension direction of one end of the auxiliary lead pin 8 inside the ceramic cover 6 is parallel to the movement direction of the moving contact 3.
[0031] refer to Figure 3 and Figure 4 The transmission assembly 4 includes a movable frame 41, a lower push rod 42 and a main spring 43. The movable frame 41 is located in the ceramic cover 6. The interior of the movable frame 41 is used for sliding connection with the moving contact 3. The sliding direction of the moving contact 3 and the movable frame 41 is parallel to the movement direction of the movable frame 41. The movable frame 41 moves along the connecting line between the moving contact 3 and the static contact 2. An auxiliary push block 44 is fixedly provided on the movable frame 41. The auxiliary push block 44 is used to control the connection of the auxiliary lead pin 8. The auxiliary push block 44 also moves in the direction of the auxiliary lead pin 8 during the process of moving the moving contact 3. The main spring 43 is arranged in the movable frame 41, and one end of the main spring 43 is fixed on the movable frame 41, and the other end is fixed on the moving contact 3. The lower push rod 42 passes through the middle sealing plate 61 for insertion into the coil 5. When in use, when the lower push rod 42 drives the movable frame 41 to move, the moving contact 3 first contacts the static contact 2 to achieve conduction of the main circuit. Since the movable frame 41 continues to move under the action of the lower push rod 42, and the main spring 43 is compressed, the auxiliary push block 44 controls the circuit connection of the auxiliary lead pin 8, thereby achieving control of multiple circuits.
[0032] refer to Figure 3 and Figure 5A column 83 is integrally formed on the middle sealing plate 61. Two columns 83 are provided and correspond to two groups of auxiliary lead pins 8 respectively. The position between the two columns 83 is used to place the transmission assembly 4. A micro switch 9 is fixedly provided on the column 83. The micro switch 9 is provided with three pins. The three pins correspond to and are electrically connected to the three auxiliary lead pins 8 in one group through a metal connecting piece 91. The metal connecting piece 91 is fixed on the column 83. When the auxiliary lead pin 8 is inserted into the ceramic cover 6, the side wall of the auxiliary lead pin 8 abuts against the metal connecting piece 91, so as to facilitate the electrical connection between the auxiliary lead pin 8 and the micro switch 9. The auxiliary push block 44 is used to push the micro switch 9 on and off. When the auxiliary push block 44 moves toward the static contact 2 along with the movable frame 41 and pushes the micro switch 9, the auxiliary lead pin 8 connected in a normally open manner to the micro switch 9 is electrically connected to the auxiliary lead pin 8 at the COM end through the micro switch 9. When the auxiliary push block 44 moves away from the static contact 2 along with the movable frame 41, the micro switch 9 is released, so that the auxiliary lead pin 8 connected in a normally closed manner is electrically connected to the auxiliary lead pin 8 at the COM end through the micro switch 9.
[0033] refer to Figure 1 A moving magnetic core 51 is fixedly arranged on the lower push rod 42, and a guide sleeve 52 is arranged on the outer cover of the moving magnetic core 51. The guide sleeve 52 is inserted into the coil 5 and fixedly connected to the middle sealing plate 61. A reset spring 53 is sleeved on the lower push rod 42. The moving magnetic core 51 slides in the guide sleeve 52. When the coil 5 is energized, the magnetic force generated by the coil 5 acts on the moving magnetic core 51, so that the moving magnetic core 51 drives the lower push rod 42, and the lower push rod 42 moves the moving contact 3 in the direction close to the static contact 2, and compresses the reset spring 53 at the same time. When the coil 5 is de-energized, the elastic force of the reset spring 53 pushes the moving contact 3 downward to move in the direction away from the static contact 2.
[0034] The working process of this embodiment: When the coil 5 is energized, the lower push rod 42 and the movable frame 41 approach the static contact 2 at the same time, so that the moving contact 3 contacts the static contact 2 first, and then the movable frame 41 continues to move, and the auxiliary push block 44 on the movable frame 41 turns on the microswitch 9. After the microswitch 9 is turned on, the auxiliary lead pin 8 connected in the normally open mode is electrically connected to the auxiliary lead pin 8 at the COM end, and at the same time, the auxiliary lead pin 8 connected in the normally closed mode is disconnected from the auxiliary lead pin 8 at the COM end, and two groups of auxiliary lead pins 8 are provided, each group of auxiliary lead pins 8 can control a circuit individually, thereby realizing the control of multiple circuits.
[0035] Embodiment 2: This embodiment discloses a multi-auxiliary circuit DC contactor, referring to Figure 6, which is different from the first embodiment in that: a slideway 831 is provided on the column 83, a metal connecting piece 91 is fixed on the auxiliary push block 44 through a connecting plate 10, and three auxiliary lead pins 8 in a group correspond to one metal connecting piece 91 respectively, wherein the height of the metal connecting piece 91 corresponding to the normally open auxiliary lead pin 8 is lower than the lowest point of the normally open auxiliary lead pin 8, so that the metal connecting piece 91 is disconnected from the normally open auxiliary lead pin 8, and the remaining two metal connecting pieces 91 are in contact with the corresponding auxiliary lead pin 8. A disconnection portion 84 is provided in the middle position of the normally closed auxiliary lead pin 8, and one end of the metal connecting piece 91 used for connecting the auxiliary lead pin 8 is provided with an elastic hook shape, and the elasticity of the metal connecting piece 91 is used to effectively electrically connect the metal connecting piece 91 to the auxiliary lead pin 8. The disconnection portion 84 is set in a curved shape, that is, when the metal connecting piece 91 moves to the highest point, one end of the hook of the metal connecting piece 91 is at the same height position as the disconnection portion 84 and separated from each other, so that the metal connecting piece 91 is disconnected from the normally closed auxiliary lead pin 8. The three metal connecting pieces 91 are integrally arranged. When the connecting plate 10 fixes the metal connecting piece 91 on the auxiliary push block 44, the auxiliary push block 44 moves, and at the same time drives the three metal connecting pieces 91 to move. Each metal connecting piece 91 corresponds to a slideway 831, and the bottom of the slideway 831 is used to abut against the metal connecting piece 91, so that when the metal connecting piece 91 contacts the auxiliary lead pin 8, the metal connecting piece 91 is clamped between the auxiliary lead pin 8 and the column 83, thereby improving the connection reliability between the metal connecting piece 91 and the auxiliary lead pin 8.
[0036] The working process of this embodiment: When the auxiliary push block 44 approaches the static contact 2 along with the movable frame 41, the metal connecting piece 91 simultaneously moves toward the direction of the auxiliary lead pin 8, so that the normally open auxiliary lead pin 8 contacts the corresponding metal connecting piece 91, thereby realizing the electrical connection between the normally open auxiliary lead pin 8 and the auxiliary lead pin 8 at the COM end. At the same time, the disconnecting portion 84 of the normally closed auxiliary lead pin 8 is at the same height as the corresponding metal connecting piece 91, thereby disconnecting the electrical connection between the normally closed auxiliary lead pin 8 and the auxiliary lead pin 8 at the COM end.
[0037] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A multi-auxiliary circuit DC contactor, characterized in that: The invention comprises a housing (1), the housing (1) being provided with at least two static contacts (2) extending into the housing (1), the housing (1) being provided with a ceramic cover (6), the static contacts (2) being inserted into the interior of the ceramic cover (6), the ceramic cover (6) being provided with a moving contact (3), the moving contact (3) being connected to a transmission assembly (4), the transmission assembly (4) comprising a movable frame (41), the moving contact (3) being connected to the movable frame (41), and the movable frame (41) driving the moving contact (3) to move in the same direction when moving. The movable frame (41) is provided with at least one group of auxiliary lead pins (8), wherein the group of auxiliary lead pins (8) has three members, one end of the auxiliary lead pin (8) is outside the ceramic cover (6) and connected to a circuit connection board (81), the circuit connection board (81) is connected to a lead wire (82) extending outside the housing (1), each lead wire (82) is electrically connected to an auxiliary lead pin (8), and the movable frame (41) is provided with an auxiliary push block (44), wherein the auxiliary push block (44) is used to control the on / off of the three auxiliary lead pins (8).
2. A multi-auxiliary circuit DC contactor according to claim 1, characterized in that: A column (83) is fixedly arranged inside the ceramic cover (6), and the column (83) is arranged corresponding to a group of auxiliary lead pins (8). A micro switch (9) is fixedly arranged on the column (83), and three pins of the micro switch (9) correspond one by one to three auxiliary lead pins (8) in a group, respectively. The micro switch (9) is pushed on or off by an auxiliary push block (44).
3. A multi-auxiliary circuit DC contactor according to claim 2, characterized in that: A plurality of metal connecting sheets (91) are fixedly arranged on the upright column (83); one side of the metal connecting sheet (91) is electrically connected to the pin of the micro switch (9), and the other side is used to abut against the side wall of the auxiliary lead pin (8).
4. The multi-auxiliary circuit DC contactor according to claim 1, characterized in that: A column (83) is arranged in the ceramic cover (6), and a slideway (831) is provided on the column (83). A metal connecting piece (91) is arranged in each slideway (831), and one end of the metal connecting piece (91) is arranged in an elastic hook shape. When the moving contact (3) is separated from the static contact (2), one of the metal connecting pieces (91) is separated from the corresponding auxiliary lead pin (8), and the other two metal connecting pieces (91) are in contact with the corresponding auxiliary lead pin (8), and one of the two auxiliary lead pins (8) in contact with the metal connecting piece (91) is provided with a disconnection portion (84). When the moving contact (3) is connected to the static contact (2), the disconnection portion (84) and the corresponding metal connecting piece (91) are at the same height and are arranged separately. The metal connecting piece (91) is fixed on the auxiliary push block (44).
5. A multi-auxiliary circuit DC contactor according to claim 4, characterized in that: One side of the metal connecting piece (91) abuts against the slideway (831), and the side of the metal connecting piece (91) away from the slideway (831) is used to abut against the auxiliary guide pin (8).
6. A multi-auxiliary circuit DC contactor according to any one of claims 1 to 5, characterized in that: The moving contact (3) is slidably connected inside the movable frame (41), and a main spring (43) is provided between the moving contact (3) and the movable frame (41). One end of the main spring (43) abuts against the moving contact (3), and the other end abuts against the movable frame (41). After the moving contact (3) contacts the static contact (2), the main spring (43) contracts, and the movable frame (41) and the auxiliary push block (44) continue to move toward the auxiliary guide pin (8).
7. A multi-auxiliary circuit DC contactor according to claim 6, characterized in that: The movable frame (41) is connected to a lower push rod (42), a moving magnetic core (51) is fixedly arranged on the lower push rod (42), a coil (5) is arranged on the outer side of the moving magnetic core (51), the coil (5) is fixed to the housing (1), and a return spring (53) is arranged on the lower push rod (42), and the return spring (53) is used to push the lower push rod (42) to move in a direction of separating the moving contact (3) from the static contact (2).
8. The multi-auxiliary circuit DC contactor according to claim 1, characterized in that: An intermediate sealing plate (61) is provided on a side of the ceramic cover (6) away from the static contact (2), the intermediate sealing plate (61) seals the ceramic cover (6), an exhaust pipe (62) is provided on the intermediate sealing plate (61), and a one-way valve (63) is installed on the exhaust pipe (62).
9. The multi-auxiliary circuit DC contactor according to claim 1, characterized in that: Two magnets (7) are fixedly arranged on the outside of the ceramic cover (6) via a fixing frame (71), and the two magnets (7) respectively correspond to the abutment points between the moving contact (3) and the two stationary contacts (2).