Contactor with arc splash isolation mechanism

Abstract

The present invention discloses a contactor with an arc splash isolation mechanism, which is mainly composed of a housing, an arc extinguishing chamber cover, a static contact, a moving contact, a central shaft, a rebound spring, an arc extinguishing chamber, a coil and an arc shield; the arc shield is in the shape of an inverted bowl; an opening is left at the center of the arc shield for the central shaft to pass through; the upper top surface of the arc shield is fixedly connected to the moving contact, and the lower opening of the arc shield is covered on the outside of the rebound spring. The present invention adds an arc shield to isolate arc splashes on the basis of the existing contactor, avoiding the accumulation of arc splashes with the increase of the number of load switching of the contactor, thereby preventing the deterioration of the breaking capacity of the contactor, and avoiding the obstruction of the action of the moving parts of the product, thereby achieving the purpose of improving the electrical life and product reliability.

Description

Technical Field

[0001] The invention relates to the technical field of contactors, and in particular to a contactor with an arc splash isolation mechanism. Background Art

[0002] In high-voltage DC circuits, contactors are usually used to control the on and off of the circuit. According to the working principle of the contactor, after the coil is energized, magnetic flux is generated in the magnetic circuit to form an electromagnetic attraction. This electromagnetic attraction overcomes the spring reaction force to attract the armature, drive the contact mechanism to operate, open the normally closed contact, close the normally open contact, interlock or connect the circuit; when the coil loses power or the voltage at both ends of the coil drops to a certain value, the electromagnetic attraction is less than the spring reaction force, so that the armature is released, the contact mechanism is reset, the circuit is disconnected or the interlock is released, and the circuit is connected and disconnected.

[0003] Figure 1 The cross-sectional view of a high-voltage DC contactor of a typical structure is mainly composed of a shell, an arc extinguishing chamber cover, a static contact, a moving contact, a central shaft, a rebound spring, an arc extinguishing chamber and a coil. The arc extinguishing chamber cover lies across the inner cavity of the shell and divides the inner cavity of the shell into two independent chambers, wherein the coil is located in the upper chamber of the shell and the arc extinguishing chamber is located in the lower chamber of the shell. The central shaft is vertically arranged in the middle of the arc extinguishing chamber cover, and the upper part of the central shaft extends into the arc extinguishing chamber, and the lower part of the central shaft extends into the coil. The rebound spring is sleeved on the outside of the central shaft. The moving contact is horizontally arranged at the upper end of the central shaft and is located in the arc extinguishing chamber. The static contact is arranged in the upper wall of the shell, and the upper part of the static contact extends outside the shell, and the lower part of the static contact extends into the arc extinguishing chamber.

[0004] During the switching process of the high-voltage DC contactor, a high-energy arc will be generated between the contacts, which will burn the contacts and produce splashes. Although most of the arc will be extinguished in the arc extinguishing chamber, since the moving parts (rebound spring and center shaft) of the contactor with the above structure are directly exposed to the arc extinguishing chamber in the closed state, a small amount of arc splashes will still adhere to the moving parts of the contactor, affecting the movement of the contactor, causing movement obstruction or even failure. Summary of the invention

[0005] The present invention aims to solve the problem that the existing contactor is prone to motion blockage or even failure due to the moving parts being directly exposed in the arc extinguishing chamber, and provides a contactor with an arc splash isolation mechanism.

[0006] To solve the above problems, the present invention is achieved through the following technical solutions:

[0007] A contactor with an arc splash isolation mechanism is mainly composed of a shell, an arc extinguishing chamber cover, a static contact, a moving contact, a central shaft, a rebound spring, an arc extinguishing chamber and a coil; the difference is that it further includes an arc isolation cover, which is in the shape of an inverted bowl; an opening is reserved at the center of the arc isolation cover for the central shaft to pass through; the upper top surface of the arc isolation cover is fixedly connected to the moving contact, and the lower opening of the arc isolation cover is covered on the outside of the rebound spring.

[0008] In the above scheme, a convex thin-walled circular ring is provided at the center of the arc extinguishing chamber cover where the central axis passes through; the rebound spring is installed between the central axis and the thin-walled circular ring; the arc isolation cover is covered on the outside of the thin-walled circular ring and has a clearance fit with the thin-walled circular ring.

[0009] In the above solution, the height of the arc shield is equal to or greater than the distance between the moving contact and the arc extinguishing chamber cover when the contactor is in the energized state.

[0010] In the above solution, the arc isolation cover and the moving contact are fixedly connected by interference fit or are an integrated structure.

[0011] Compared with the prior art, the present invention adds an arc shield to isolate arc splashes on the basis of the existing contactor, thereby avoiding the accumulation of arc splashes and deteriorating the breaking capacity of the contactor as the number of load switching times of the contactor increases, so as to avoid hindering the movement of the moving parts of the product, thereby achieving the purpose of improving the electrical life and product reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a cross-sectional view of an existing high-voltage DC contactor.

[0013] Figure 2 It is a cross-sectional view of the contactor with the arc splash isolation mechanism of the present invention in the released state.

[0014] Figure 3 The present invention is a cross-sectional view of a contactor with an arc splash isolation mechanism in a closed state.

[0015] Figure 4 It is a structural schematic diagram of the arc spatter isolation mechanism.

[0016] Numbers in the figure: 1. Shell; 2. Static contact; 3. Moving contact; 4. Center axis; 5. Rebound spring; 6. Arc extinguishing chamber; 7. Coil; 8. Arc extinguishing chamber cover; 8-1. Thin-walled ring; 9. Arc isolation cover. DETAILED DESCRIPTION

[0017] 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 in combination with specific examples and with reference to the accompanying drawings. It should be noted that the directional terms mentioned in the examples, such as "upper", "lower", "middle", "left", "right", "front", "back", etc., are only referenced to the directions of the accompanying drawings. Therefore, the directions used are only used for illustration and are not used to limit the scope of protection of the present invention.

[0018] In view of the fact that the existing contactor does not take into account that the moving parts of the contactor, namely the rebound spring 5 and the central shaft 4, will be directly exposed to the arc extinguishing chamber 6 in the energized state, thereby causing a small amount of arc splashes to adhere to the moving parts of the contactor and affect the operation of the contactor, the present invention adds an arc isolation cover 9 on the basis of the existing contactor to isolate the arc splashes, that is, a contactor with an arc splash isolation mechanism designed by the present invention, such as Figure 2 and 3 As shown, it is mainly composed of a housing 1, an arc extinguishing chamber cover 8, a static contact 2, a moving contact 3, a central shaft 4, a rebound spring 5, an arc extinguishing chamber 6, a coil 7 and an arc isolation cover 9.

[0019] The arc extinguishing chamber cover 8 lies across the inner cavity of the housing 1 and divides the inner cavity of the housing 1 into two independent chambers, wherein the coil 7 is located in the upper chamber of the housing 1 and the arc extinguishing chamber 6 is located in the lower chamber of the housing 1. The central axis 4 is vertically arranged in the middle of the arc extinguishing chamber cover 8, and the upper part of the central axis 4 extends into the arc extinguishing chamber 6, and the lower part of the central axis 4 extends into the coil 7. The rebound spring 5 is sleeved on the outer side of the central axis 4. The moving contact 3 is horizontally arranged at the upper end of the central axis 4 and is located in the arc extinguishing chamber 6. The static contact 2 is arranged in the upper wall of the housing 1, and the upper part of the static contact 2 extends outside the housing 1, and the lower part of the static contact 2 extends into the arc extinguishing chamber 6. The arc shield 9 is in the shape of an inverted bowl as a whole. An opening is left at the center of the arc shield 9 for the central axis 4 to pass through. The top surface of the arc shield 9 is fixedly connected to the moving contact 3, and the lower opening of the arc shield 9 covers the outside of the rebound spring 5. The arc shield 9 covers the outside of the rebound spring 5 and the central shaft 4, and moves with the movement of the moving contact 3, which can prevent the rebound spring 5 and the central shaft 4 from being directly exposed to the arc extinguishing chamber 6, so that the arc splashes will not directly adhere to the moving parts of the contactor, so that the moving parts of the contactor can maintain a smooth state for a long time. Figure 3 .

[0020] In order to improve the arc isolation effect, a convex thin-walled circular ring 8-1 can be provided at the center of the arc extinguishing chamber cover 8 where the central axis 4 penetrates, and the rebound spring 5 is installed between the central axis 4 and the thin-walled circular ring 8-1. In this way, the arc shield 9 can cover the outside of the thin-walled circular ring 8-1, and there is a gap fit between the thin-walled circular ring 8-1. In this way, the arc shield 9 is stuck in the slot of the moving contact 3, and then the elastic force applied to the arc shield 9 by the rebound spring 5 makes the arc shield 9 move with the movement of the moving contact 3; the arc extinguishing chamber cover 8 plate is designed with a thin-walled circular ring 8-1, which is in a gap fit with the arc shield 9, so that when the contactor is in the on and off state, it is ensured that the moving parts such as the central axis 4 and the spring are not exposed in the arc extinguishing chamber 6. The inner wall of the arc shield 9 and the outer wall of the arc extinguishing chamber cover 8 are in a gap fit, and the length of the overlap between the two needs to ensure that the contactor has a remaining overlap part in both the suction and release states, and ensure that the moving parts of the contactor are always isolated from the arc splashes during the entire movement process. That is, the height of the arc isolation cover 9 should be equal to or greater than the distance between the moving contact 3 and the arc extinguishing chamber cover 8 when the contactor is in the energized state. In this way, even in the energized state, that is, when the distance between the moving contact 3 and the arc extinguishing chamber cover 8 is the farthest, it can still be ensured that the arc isolation cover 9 can cover the outside of the rebound spring 5 and the center axis 4, and always realize the isolation function to minimize the splashing of arc splashes into it.

[0021] In the specific design, the arc shield 9 and the moving contact 3 are fixedly connected by interference fit or are an integrated structure. In view of the fact that the arc shield 9 and the moving contact 3 adopt interference fit, it is necessary to consider the pressure of the rebound spring 5, that is, the initial pressure and final pressure of the rebound spring 5, to ensure that the arc shield 9 and the moving contact 3 will not be disconnected, and to fully consider the environmental indicators of the contactor (such as impact 20g). Therefore, in the preferred embodiment of the present invention, the arc shield 9 and the moving contact 3 are designed as an integral part, which can avoid the arc shield 9 and the moving contact 3 from being disconnected in the above design.

[0022] It should be noted that although the embodiments of the present invention described above are illustrative, they are not intended to limit the present invention, and therefore the present invention is not limited to the above specific embodiments. Without departing from the principles of the present invention, any other embodiments obtained by those skilled in the art under the guidance of the present invention are deemed to be within the protection of the present invention.

Claims

1. A contactor with an arc splash isolation mechanism, which mainly consists of a housing (1), an arc extinguishing chamber cover (8), a stationary contact (2), a moving contact (3), a center shaft (4), a rebound spring (5), an arc extinguishing chamber (6) and a coil (7); wherein: It further comprises an arc shield (9) which is in the shape of an inverted bowl; an opening is left at the center of the arc shield (9) for the central axis (4) to pass through; the upper top surface of the arc shield (9) is fixedly connected to the moving contact (3) to form an integrated structure, and the lower opening of the arc shield (9) is covered on the outside of the rebound spring (5); a convex thin-walled circular ring (8-1) is provided at the center of the arc extinguishing chamber cover (8) for the central axis (4) to pass through; the rebound spring (5) is installed between the central axis (4) and the thin-walled circular ring (8-1); the arc shield (9) covers the outside of the thin-walled circular ring (8-1) and is gap-fitted with the thin-walled circular ring (8-1), and the overlapping length of the two is required to ensure that there is a remaining overlapping portion when the contactor is in the attracted and released states.

2. The contactor with arc splash isolation mechanism according to claim 1, characterized in that: The height of the arc shield (9) is equal to or greater than the distance between the moving contact (3) and the arc extinguishing chamber cover (8) of the contactor in the energized state.

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