CN219144078U

CN219144078U - Moving terminal assembly for contactor and contactor

Info

Publication number: CN219144078U
Application number: CN202222476524.0U
Authority: CN
Inventors: 陈海林; 张晓宁
Original assignee: Tyco Electronics Shanghai Co Ltd
Current assignee: Tyco Electronics Shanghai Co Ltd
Priority date: 2022-09-19
Filing date: 2022-09-19
Publication date: 2023-06-06
Anticipated expiration: 2032-09-19

Abstract

The utility model discloses a movable terminal assembly for a contactor and a contactor comprising the same. The movable terminal assembly includes a movable terminal, a first insulating member, and an auxiliary contact driving member. The movable terminal is adapted to move between an open position separated from the stationary terminal of the contactor and a closed position in contact with the stationary terminal. A first insulator is secured to the movable terminal for electrically isolating the movable terminal from a drive shaft of the contactor. An auxiliary contact drive is secured to the movable terminal or the first insulator for urging the auxiliary contacts of the contactor to a closed position. Therefore, in the utility model, when the movable terminal is moved to the closed position, the auxiliary contact driving member stops moving, so that the auxiliary contact can be effectively prevented from being damaged by excessive pushing.

Description

Moving terminal assembly for contactor and contactor

Technical Field

The present utility model relates to a moving terminal assembly for a contactor and a contactor including the same.

Background

In the prior art, a direct current contactor is required to be designed with auxiliary contacts, particularly for high-current and high-voltage application, the on-off state of a main contact is required to be monitored through the on-off state of the auxiliary contacts, so that the system can respond to abnormal conditions through signals of the auxiliary contacts, and the safety of the system is ensured. In the prior art, the auxiliary contact is usually pushed directly by hard contact between the driving shaft and the auxiliary push rod, and a buffer spring is arranged below the movable terminal of the main contact to realize over-travel. After the main contact is closed, the drive shaft continues to move upward to complete the over-travel portion based on the closing reliability requirement. At this stage the auxiliary contacts are at risk of being damaged by being pushed too far up as the drive shaft moves further upwards. During the main contact opening process, if the main contact is welded, the auxiliary contact may be opened by the advance downward movement of the drive shaft, which causes the main contact and the auxiliary contact to be inconsistent in state, so that the state of the main contact cannot be accurately monitored through the state of the auxiliary contact.

Disclosure of Invention

The present utility model is directed to solving at least one of the above-mentioned problems and disadvantages of the prior art.

According to one aspect of the present utility model, a moving terminal assembly for a contactor is provided. The movable terminal assembly includes a movable terminal, a first insulating member, and an auxiliary contact driving member. The movable terminal is adapted to move between an open position separated from the stationary terminal of the contactor and a closed position in contact with the stationary terminal. A first insulator is secured to the movable terminal for electrically isolating the movable terminal from a drive shaft of the contactor. An auxiliary contact drive is secured to the movable terminal or the first insulator for urging the auxiliary contacts of the contactor to a closed position.

According to an exemplary embodiment of the utility model, the first insulating member has a housing chamber with an open top, and the auxiliary contact driving member is made of an insulating material and covers the top opening of the housing chamber of the first insulating member such that the upper end of the driving shaft is enclosed in the housing chamber.

According to another exemplary embodiment of the utility model, the auxiliary contact drive member is bonded and fixed to the first insulating member by means of an adhesive; or the auxiliary contact driving member is snapped onto the first insulating member.

According to another exemplary embodiment of the present utility model, the first insulating member and the auxiliary contact driving member are formed as one piece.

According to another exemplary embodiment of the present utility model, the first insulating member includes: a peripheral wall and a bottom wall enclosing the accommodation chamber; and a cylindrical lower end portion extending downward from the bottom wall and inserted and fixed into the through hole on the movable terminal, an inner cavity of the cylindrical lower end portion communicating with the accommodation chamber to allow an upper end of the drive shaft to protrude into the accommodation chamber through the inner cavity of the cylindrical lower end portion.

According to another exemplary embodiment of the present utility model, the auxiliary contact driving member includes: a top cover part for covering the top opening of the accommodating chamber; and a pushing portion extending upward from the top cover portion for pushing the auxiliary contact.

According to another exemplary embodiment of the present utility model, the first insulating member is an injection molded member formed by insert injection molding, and the moving terminal is an insert member when the first insulating member is injection molded such that the first insulating member is directly engaged with the moving terminal.

According to another aspect of the present utility model, there is provided a contactor comprising: the movable terminal assembly; and the driving assembly is used for driving the movable terminal assembly to move. The drive assembly includes: a driving shaft having an upper end movably installed in the first insulating member; a buffer spring positioned below the movable terminal and compressed between the driving shaft and the movable terminal; the second insulating piece is sleeved on the driving shaft and used for electrically isolating the driving shaft from the buffer spring; and the clamping ring is clamped on the driving shaft and used for preventing the driving shaft from being separated from the movable terminal.

According to another exemplary embodiment of the present utility model, the contactor further comprises: and the movable terminal is suitable for being driven by the driving shaft to move from an open position separated from the fixed terminal to a closed position contacted with the fixed terminal.

According to another exemplary embodiment of the present utility model, the contactor further comprises: an auxiliary contact disposed above the auxiliary contact driving member and including an auxiliary movable terminal adapted to be moved from an open position separated from the auxiliary stationary terminal to a closed position contacting the auxiliary stationary terminal by an urging of the auxiliary contact driving member.

According to another exemplary embodiment of the present utility model, the auxiliary moving terminal is moved to a closing position before the moving terminal during the driving of the moving terminal toward the stationary terminal by the driving shaft, so that the auxiliary contact is closed before the main contact.

According to another exemplary embodiment of the present utility model, the second insulating member includes: a cylindrical main body sleeved on the driving shaft; and a positioning flange formed at the lower end of the cylindrical body, a radially protruding support step being formed on the driving shaft, the positioning flange being supported on the support step, an upper end of the buffer spring being abutted on the movable terminal, and a lower end of the buffer spring being abutted on the positioning flange of the second insulator.

According to another exemplary embodiment of the present utility model, the upper end of the cylindrical body of the second insulator is movably inserted into the inner cavity of the cylindrical lower end portion of the first insulator.

According to another exemplary embodiment of the present utility model, a clamping groove is formed at an upper end of the driving shaft, and the clamping ring is clamped in the clamping groove and abuts against an upper end face of the cylindrical body of the second insulating member.

According to another exemplary embodiment of the present utility model, the driving assembly further comprises: a coil bobbin; and a coil wound around the bobbin. When the coil is energized, the drive shaft moves upward under the influence of electromagnetic force to drive the movable terminal to move to a closed position.

According to another exemplary embodiment of the present utility model, the contactor further comprises: an insulating inner housing having a bottom opening; and an insulating bottom plate mounted on the bottom opening of the insulating inner case, the insulating inner case and the insulating bottom plate enclosing an arc extinguishing chamber in which the movable terminal assembly is accommodated.

According to another exemplary embodiment of the present utility model, the contactor further comprises: and the static terminal is fixed to the insulating bracket and penetrates through the top wall of the insulating inner shell to enter the arc extinguishing chamber.

According to another exemplary embodiment of the present utility model, the driving assembly further comprises: a magnetic conductive plate disposed between the top of the bobbin and the bottom of the insulating base plate; a magnetic core movably disposed in the bobbin; and a return spring compressed between the magnetic core and the magnetic conductive plate or the insulating base plate, the driving shaft passing through the insulating base plate and the magnetic conductive plate and being connected to the magnetic core. When the coil is powered off, the driving shaft moves downwards under the action of the reset force of the reset spring so as to drive the movable terminal to move to the disconnection position.

According to another exemplary embodiment of the present utility model, the contactor further comprises: and the metal inner shell is used for accommodating the movable terminal assembly, the driving assembly, the insulating inner shell, the insulating bottom plate and the insulating bracket.

According to another exemplary embodiment of the present utility model, the contactor further comprises: an insulating outer case in which the metal inner case is accommodated; and an insulating end cap mounted to the end opening of the insulating housing.

According to another exemplary embodiment of the present utility model, the stationary terminal has an outer end exposed from the insulating end cap, and the contactor further includes an electrical connector connected to the outer end of the stationary terminal for electrically connecting the stationary terminal to a connection terminal.

According to another exemplary embodiment of the present utility model, the electrical connector comprises: the bolt is in threaded connection with the outer end part of the static terminal; and the nut is in threaded connection with the bolt.

According to another exemplary embodiment of the present utility model, a partition wall is formed on the top surface of the insulating end cap, the partition wall spacing the outer ends of the pair of static terminals to increase a creepage distance between the outer ends of the pair of static terminals.

According to another exemplary embodiment of the present utility model, the contactor further comprises: and the gas charging pipe penetrates through the insulating end cover and stretches into the arc extinguishing chamber, and is used for filling inert protective gas into the arc extinguishing chamber.

In the foregoing exemplary embodiments according to the present utility model, the auxiliary contact driving member moves in synchronization with the movable terminal, and therefore, when the movable terminal is moved to the closed position, the auxiliary contact driving member stops moving, so that the auxiliary contact can be effectively prevented from being excessively pushed.

Further, in the foregoing respective exemplary embodiments according to the present utility model, since the auxiliary contact driving member moves in synchronization with the movable terminal, it is possible to ensure that the states of the auxiliary contact and the main contact remain identical, so that the state of the main contact can be accurately monitored according to the state of the auxiliary contact.

Further, in the foregoing exemplary embodiments according to the present utility model, the upper end of the driving shaft is enclosed in the accommodating chamber of the first insulating member, the spatial insulation between the driving shaft and the main contact is enhanced, and the insulation performance of the contactor is improved.

Other objects and advantages of the present utility model will become apparent from the following description of the utility model with reference to the accompanying drawings, which provide a thorough understanding of the present utility model.

Drawings

Fig. 1 shows a schematic perspective view of a contactor according to an exemplary embodiment of the utility model;

fig. 2 shows an axial cross-section of a contactor according to an exemplary embodiment of the utility model.

Detailed Description

The technical scheme of the utility model is further specifically described below through examples and with reference to the accompanying drawings. In the specification, the same or similar reference numerals denote the same or similar components. The following description of embodiments of the present utility model with reference to the accompanying drawings is intended to illustrate the general inventive concept and should not be taken as limiting the utility model.

Furthermore, in the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. It may be evident, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are shown in the drawings in order to simplify the drawings.

According to one general technical concept of the present utility model, a moving terminal assembly for a contactor is provided. The movable terminal assembly includes a movable terminal, a first insulating member, and an auxiliary contact driving member. The movable terminal is adapted to move between an open position separated from the stationary terminal of the contactor and a closed position in contact with the stationary terminal. A first insulator is secured to the movable terminal for electrically isolating the movable terminal from a drive shaft of the contactor. An auxiliary contact drive is secured to the movable terminal or the first insulator for urging the auxiliary contacts of the contactor to a closed position.

According to another general technical concept of the present utility model, there is provided a contactor including: a moving terminal assembly; and the driving assembly is used for driving the movable terminal assembly to move. The drive assembly includes: a driving shaft having an upper end movably installed in the first insulating member; a buffer spring positioned below the movable terminal and compressed between the driving shaft and the movable terminal; the second insulating piece is sleeved on the driving shaft and used for electrically isolating the driving shaft from the buffer spring; and the clamping ring is clamped on the driving shaft and used for preventing the driving shaft from being separated from the movable terminal.

Fig. 1 shows a schematic perspective view of a contactor according to an exemplary embodiment of the utility model; fig. 2 shows an axial cross-section of a contactor according to an exemplary embodiment of the utility model.

As shown in fig. 1 and 2, in one exemplary embodiment of the present utility model, a moving terminal assembly for a contactor is disclosed. The moving terminal assembly includes: a movable terminal 1a, a first insulating member 4, and an auxiliary contact driving member 5. The movable terminal 1a is adapted to move between an open position separated from the stationary terminal 1b of the contactor and a closed position in contact with the stationary terminal 1 b. The first insulator 4 is fixed to the moving terminal 1a for electrically isolating the moving terminal 1a from the drive shaft 3 of the contactor. An auxiliary contact driving member 5 is fixed to the movable terminal 1a or the first insulating member 4 for pushing the auxiliary contact 2 of the contactor to the closed position.

As shown in fig. 1 and 2, in the illustrated embodiment, the first insulating member 4 has a housing chamber 4c open at the top, and the auxiliary contact driving member 5 is made of an insulating material and covers the top opening of the housing chamber 4c of the first insulating member 4 such that the upper end of the driving shaft 3 is enclosed in the housing chamber 4 c.

As shown in fig. 1 and 2, in the illustrated embodiment the auxiliary contact drive 5 is snapped onto the first insulator 4. However, the utility model is not limited to the illustrated embodiment, for example, the auxiliary contact driving member 5 may be bonded and fixed to the first insulating member 4 by an adhesive.

As shown in fig. 1 and 2, in the illustrated embodiment, the first insulating member 4 and the auxiliary contact driving member 5 are formed as one piece.

As shown in fig. 1 and 2, in the illustrated embodiment, the first insulating member 4 includes: a peripheral wall 4a and a bottom wall 4d enclosing a housing chamber 4c; and a cylindrical lower end portion 4b extending downward from the bottom wall 4d and inserted and fixed into the through hole on the movable terminal 1 a. The inner cavity of the cylindrical lower end portion 4b communicates with the accommodation chamber 4c to allow the upper end of the drive shaft 3 to protrude into the accommodation chamber 4c via the inner cavity of the cylindrical lower end portion 4 b.

As shown in fig. 1 and 2, in the illustrated embodiment, the auxiliary contact driving member 5 includes: a top cover part 5a covering the top opening of the housing chamber 4c; and a pushing portion 5b extending upward from the top cover portion 5a for pushing the auxiliary contact 2.

As shown in fig. 1 and 2, in the illustrated embodiment, the first insulating member 4 is an injection-molded member formed by insert injection molding, and the movable terminal 1a is an insert member when the first insulating member 4 is injection-molded, so that the first insulating member 4 is directly engaged with the movable terminal 1 a.

In another exemplary embodiment of the present utility model, as shown in fig. 1 and 2, a contactor is also disclosed. The contactor includes: the movable terminal assembly and the driving assembly. The driving component is used for driving the movable terminal component to move. The drive assembly includes: a drive shaft 3 whose upper end is movably installed in the first insulating member 4; a buffer spring 7 positioned below the movable terminal 1a and compressed between the driving shaft 3 and the movable terminal 1 a; a second insulating member 6, which is sleeved on the driving shaft 3, for electrically isolating the driving shaft 3 from the buffer spring 7; and a snap ring 3a located in the first insulator 4 and caught on the drive shaft 3 for preventing the drive shaft 3 from being separated from the first insulator 4 and the movable terminal 1 a.

As shown in fig. 1 and 2, in the illustrated embodiment, the contactor further includes a stationary terminal 1b, the stationary terminal 1b being disposed above the movable terminal 1 a. The movable terminal 1a and the stationary terminal 1b constitute a main contact 1 of the contactor, the movable terminal 1a being adapted to be moved from an open position separated from the stationary terminal 1b to a closed position in contact with the stationary terminal 1b by the drive of the drive shaft 3.

As shown in fig. 1 and 2, in the illustrated embodiment, the contactor further comprises an auxiliary contact 2, the auxiliary contact 2 being arranged above the auxiliary contact drive 5 and comprising an auxiliary movable terminal 2a and an auxiliary stationary terminal 2b. The auxiliary movable terminal 2a is adapted to be moved from an open position separated from the auxiliary stationary terminal 2b to a closed position in contact with the auxiliary stationary terminal 2b by pushing of the auxiliary contact driving piece 5.

As shown in fig. 1 and 2, in the illustrated embodiment, during the movement of the drive shaft 3 driving the movable terminal 1a toward the stationary terminal 1b, the auxiliary movable terminal 2a is moved to the closed position before the movable terminal 1a, so that the auxiliary contact 2 is closed before the main contact 1.

As shown in fig. 1 and 2, in the illustrated embodiment, the second insulating member 6 includes: a tubular main body 6a fitted over the drive shaft 3; and a positioning flange 6b formed at the lower end of the cylindrical body 6 a. A radially protruding support step 3b is formed on the drive shaft 3, and the positioning flange 6b is supported on the support step 3 b. The upper end of the buffer spring 7 abuts on the movable terminal 1a, and the lower end of the buffer spring 7 abuts on the positioning flange 6b of the second insulator 6.

As shown in fig. 1 and 2, in the illustrated embodiment, the upper end of the cylindrical body 6a of the second insulator 6 is movably inserted into the inner cavity of the cylindrical lower end portion 4b of the first insulator 4.

As shown in fig. 1 and 2, in the illustrated embodiment, a clamping groove is formed at the upper end of the drive shaft 3, and a snap ring 3a is clamped in the clamping groove and abuts against the upper end face of the cylindrical body 6a of the second insulator 6.

As shown in fig. 1 and 2, in the illustrated embodiment, the drive assembly further comprises: a bobbin 10; and a coil wound around the coil bobbin 10. When the coil is energized, the drive shaft 3 moves upward under the influence of electromagnetic force to drive the movable terminal 1a to move to the closed position.

As shown in fig. 1 and 2, in the illustrated embodiment, the contactor further includes: an insulating inner case 8 having a bottom opening; and an insulating base plate 8a mounted on the bottom opening of the insulating inner case 8. The insulating inner case 8 and the insulating base plate 8a enclose an arc extinguishing chamber in which the movable terminal assembly is accommodated.

As shown in fig. 1 and 2, in the illustrated embodiment, the contactor further comprises an insulating support 17, the insulating support 17 being provided on the top wall of the insulating inner housing 8. The static terminal 1b is fixed to the insulating bracket 17 and passes through the top wall of the insulating inner housing 8 into the arc extinguishing chamber.

As shown in fig. 1 and 2, in the illustrated embodiment, the drive assembly further comprises: a magnetic conductive plate 9 provided between the top of the bobbin 10 and the bottom of the insulating base plate 8 a; a magnetic core 11 movably disposed in the coil bobbin 10; and a return spring 12 compressed between the magnetic core 11 and the magnetic conductive plate 9 or the insulating base plate 8 a. The drive shaft 3 passes through the insulating base plate 8a and the magnetic conductive plate 9 and is connected to the magnetic core 11. When the coil is deenergized, the drive shaft 3 moves downward by the restoring force of the restoring spring 12 to drive the movable terminal 1a to move to the off position.

As shown in fig. 1 and 2, in the illustrated embodiment, the contactor further comprises a metal inner housing 13. The movable terminal assembly, the driving assembly, the insulating inner housing 8, the insulating base plate 8a, and the insulating holder 17 are accommodated in the metal inner housing 13.

As shown in fig. 1 and 2, in the illustrated embodiment, the contactor further includes: an insulating outer case 14, the metal inner case 13 being accommodated in the insulating outer case 14; and an insulating end cap 15 mounted to the end opening of the insulating housing 14.

As shown in fig. 1 and 2, in the illustrated embodiment, the stationary terminal 1b has an outer end portion exposed from the insulating end cap 15, and the contactor further includes

electrical connectors

1c, 1d connected to the outer end portion of the stationary terminal 1b for electrically connecting the stationary terminal 1b to the connection terminal.

As shown in fig. 1 and 2, in the illustrated embodiment, the

electrical connectors

1c, 1d comprise: a bolt 1c screwed to the outer end of the stationary terminal 1 b; and a nut 1d screwed to the bolt 1 c.

As shown in fig. 1 and 2, in the illustrated embodiment, a partition wall 15a is formed on the top surface of the insulating end cover 15, the partition wall 15a separating the outer end portions of the pair of stationary terminals 1b to increase the creepage distance between the outer end portions of the pair of stationary terminals 1 b.

As shown in fig. 1 and 2, in the illustrated embodiment, the contactor further comprises an inflation tube 16, the inflation tube 16 extending through the insulating end cap 15 and into the arc chute for filling the arc chute with an inert shielding gas. After filling with inert shielding gas, the inflation tube 16 is plugged to prevent gas leakage.

As shown in fig. 1 and 2, in the illustrated embodiment, the auxiliary contact drive is connected to the movable terminal or to a first insulator over the movable terminal. During the closing process of the main contact 1, the auxiliary contact 2 is firstly switched on, and then the driving shaft 3 completes the over-travel part of the auxiliary contact 2; then the main contact 1 is turned on, the movable terminal 1a and the auxiliary contact driving member 5 stop moving upward together, and the auxiliary contact 2 is prevented from being damaged by excessive pushing. Finally, the drive shaft 3 moves further upward, completing the over-stroke portion of the main contact 1. In the process of opening the main contact 1, if the main contact 1 is adhered and fused, the movable terminal 1a cannot move downwards, the auxiliary contact 2 cannot be opened, the states of the main contact 1 and the auxiliary contact 2 are ensured to be consistent, and accurate monitoring is realized.

As shown in fig. 1 and 2, in the illustrated embodiment, when the coil is energized, the movable terminal 1a pushes the first insulating member 4 together to move upward. When the coil is powered off, the first insulating part 4 is driven by the snap ring 3a on the driving shaft 3 to move downwards to reset by the counterforce of the auxiliary contact 2 in the later period. In the illustrated embodiment, the auxiliary contact driving member 5 does not merely push the auxiliary contact 2 to the closed position, but it moves up and down with the movable terminal assembly to effect the closing and opening of the auxiliary contact 2.

It will be appreciated by those skilled in the art that the above-described embodiments are exemplary and that modifications may be made to the embodiments described in various embodiments without structural or conceptual aspects and that these variations may be resorted to without departing from the scope of the utility model.

Although the present utility model has been described with reference to the accompanying drawings, the examples disclosed in the drawings are intended to illustrate preferred embodiments of the utility model and are not to be construed as limiting the utility model.

Although a few embodiments of the present general inventive concept have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the claims and their equivalents.

It should be noted that the word "comprising" does not exclude other elements or steps, and that the word "a" or "an" does not exclude a plurality. In addition, any element numbers of the claims should not be construed as limiting the scope of the utility model.

Claims

1. A moving terminal assembly for a contactor, comprising:

a movable terminal (1 a) adapted to move between an open position separated from a stationary terminal (1 b) of the contactor and a closed position in contact with the stationary terminal (1 b);

a first insulator (4) fixed to the moving terminal (1 a) for electrically isolating the moving terminal (1 a) from a drive shaft (3) of a contactor; and

an auxiliary contact driving member (5) fixed to the movable terminal (1 a) or the first insulating member (4) for pushing the auxiliary contact (2) of the contactor to a closed position.

2. The moving terminal assembly of claim 1, wherein:

the first insulating member (4) has a housing chamber (4 c) open at the top, and the auxiliary contact driving member (5) is made of an insulating material and covers the top opening of the housing chamber (4 c) of the first insulating member (4) so that the upper end of the driving shaft (3) is enclosed in the housing chamber (4 c).

3. The moving terminal assembly of claim 1, wherein:

-said auxiliary contact driving member (5) is bonded to said first insulating member (4) by means of an adhesive; or alternatively

The auxiliary contact drive (5) is snapped onto the first insulator (4).

4. The moving terminal assembly of claim 1, wherein:

the first insulating member (4) and the auxiliary contact driving member (5) are formed as a single piece.

5. The moving terminal assembly of claim 2, wherein:

the first insulator (4) comprises:

a peripheral wall (4 a) and a bottom wall (4 d) enclosing the accommodation chamber (4 c); and

a cylindrical lower end portion (4 b) extending downward from the bottom wall (4 d) and inserted and fixed into a through hole on the movable terminal (1 a),

the inner cavity of the cylindrical lower end portion (4 b) communicates with the accommodating chamber (4 c) to allow the upper end of the drive shaft (3) to extend into the accommodating chamber (4 c) via the inner cavity of the cylindrical lower end portion (4 b).

6. The moving terminal assembly of claim 2, wherein:

the auxiliary contact driving member (5) includes:

a top cover part (5 a) for covering the top opening of the accommodating chamber (4 c); and

and a pushing part (5 b) extending upwards from the top cover part (5 a) and used for pushing the auxiliary contact (2).

7. The moving terminal assembly of claim 2, wherein:

the first insulating member (4) is an injection molded member formed by insert molding, and the movable terminal (1 a) is an insert member when the first insulating member (4) is injection molded, so that the first insulating member (4) is directly joined with the movable terminal (1 a).

8. A contactor, comprising:

the dynamic terminal assembly of any one of claims 1-7; and

the driving component is used for driving the moving terminal component to move,

the drive assembly includes:

a drive shaft (3) whose upper end is movably installed into the first insulating member (4);

a buffer spring (7) positioned below the movable terminal (1 a) and compressed between the drive shaft (3) and the movable terminal (1 a);

a second insulating member (6) sleeved on the driving shaft (3) for electrically isolating the driving shaft (3) from the buffer spring (7); and

and a clamping ring (3 a) clamped on the driving shaft (3) and used for preventing the driving shaft (3) from being separated from the movable terminal (1 a).

9. The contactor according to claim 8, further comprising:

a stationary terminal (1 b) arranged above the movable terminal (1 a),

the moving terminal (1 a) and the stationary terminal (1 b) constitute a main contact (1) of the contactor, the moving terminal (1 a) being adapted to be moved from an open position separated from the stationary terminal (1 b) to a closed position in contact with the stationary terminal (1 b) under the drive of the drive shaft (3).

10. The contactor according to claim 9, further comprising:

an auxiliary contact (2) arranged above the auxiliary contact driving member (5) and comprising an auxiliary movable terminal (2 a) and an auxiliary stationary terminal (2 b),

the auxiliary movable terminal (2 a) is adapted to be moved from an open position separated from the auxiliary stationary terminal (2 b) to a closed position in contact with the auxiliary stationary terminal (2 b) under pushing of the auxiliary contact driving member (5).

11. The contactor according to claim 10, wherein:

during the driving of the movable terminal (1 a) towards the stationary terminal (1 b) by the driving shaft (3), the auxiliary movable terminal (2 a) is moved to a closed position before the movable terminal (1 a) such that the auxiliary contact (2) is closed before the main contact (1).

12. The contactor according to claim 8, wherein:

the second insulator (6) comprises:

a tubular main body (6 a) which is sleeved on the driving shaft (3); and

a positioning flange (6 b) formed at the lower end of the cylindrical body (6 a),

a radially projecting support step (3 b) is formed on the drive shaft (3), the positioning flange (6 b) being supported on the support step (3 b),

the upper end of the buffer spring (7) is abutted against the movable terminal (1 a), and the lower end of the buffer spring (7) is abutted against the positioning flange (6 b) of the second insulating member (6).

13. The contactor according to claim 12, wherein:

the upper end of the cylindrical main body (6 a) of the second insulator (6) is movably inserted into the inner cavity of the cylindrical lower end (4 b) of the first insulator (4).

14. The contactor according to claim 12, wherein:

a clamping groove is formed at the upper end of the driving shaft (3), and the clamping ring (3 a) is clamped in the clamping groove and abuts against the upper end face of the cylindrical main body (6 a) of the second insulating piece (6).

15. The contactor according to claim 10, wherein:

the drive assembly further includes:

a coil bobbin (10); and

a coil wound around the bobbin (10),

when the coil is energized, the drive shaft (3) moves upward under the influence of electromagnetic force to drive the movable terminal (1 a) to move to a closed position.

16. The contactor according to claim 15, further comprising:

an insulating inner housing (8) having a bottom opening; and

an insulating base plate (8 a) mounted on the bottom opening of the insulating inner case (8),

the insulating inner shell (8) and the insulating base plate (8 a) enclose an arc extinguishing chamber in which the moving terminal assembly is accommodated.

17. The contactor according to claim 16, further comprising:

an insulating bracket (17) arranged on the top wall of the insulating inner shell (8),

the static terminal (1 b) is fixed to the insulating support (17) and passes through the top wall of the insulating inner housing (8) into the arc extinguishing chamber.

18. The contactor according to claim 17, wherein:

the drive assembly further includes:

a magnetic conductive plate (9) provided between the top of the bobbin (10) and the bottom of the insulating base plate (8 a);

a magnetic core (11) movably disposed in the bobbin (10); and

a return spring (12) compressed between the magnetic core (11) and the magnetic conductive plate (9) or the insulating base plate (8 a),

the drive shaft (3) passes through the insulating base plate (8 a) and the magnetic conductive plate (9) and is connected to the magnetic core (11),

when the coil is deenergized, the driving shaft (3) moves downwards under the action of the restoring force of the restoring spring (12) to drive the movable terminal (1 a) to move to the disconnection position.

19. The contactor according to claim 18, further comprising:

and the metal inner shell (13) is used for accommodating the movable terminal assembly, the driving assembly, the insulating inner shell (8), the insulating bottom plate (8 a) and the insulating bracket (17).

20. The contactor according to claim 19, further comprising:

-an insulating outer shell (14), said metal inner shell (13) being housed in said insulating outer shell (14); and

an insulating end cap (15) is mounted to the end opening of the insulating housing (14).

21. The contactor according to claim 20, wherein:

the stationary terminal (1 b) has an outer end exposed from the insulating end cap (15), and the contactor further includes an electrical connector connected to the outer end of the stationary terminal (1 b) for electrically connecting the stationary terminal (1 b) to a connection terminal.

22. The contactor according to claim 21, wherein:

the electrical connector includes:

a bolt (1 c) which is in threaded connection with the outer end part of the static terminal (1 b); and

and the nut (1 d) is connected to the bolt (1 c) in a threaded manner.

23. The contactor according to claim 21, wherein:

a partition wall (15 a) is formed on the top surface of the insulating end cover (15), and the partition wall (15 a) partitions the outer end parts of the pair of static terminals (1 b) to increase the creepage distance between the outer end parts of the pair of static terminals (1 b).

24. The contactor according to claim 20, further comprising:

and an inflation tube (16) penetrates through the insulating end cover (15) and extends into the arc extinguishing chamber, and is used for filling inert protective gas into the arc extinguishing chamber.