Movable Contact Module, Movable Contact Assembly, Movable Contact Device and Contactor

A movable contact module for a contactor comprises an insulating member and a movable contact. The insulating member includes an insulating body having a through hole penetrating therethrough, and a peripheral wall protruding from the insulating body and surrounding an opening of the through hole. The movable contact has a fixed portion fixed in the insulating body, and an exposed portion exposed from the insulating body. The fixed portion of the movable contact is surrounded by the insulating body so that the movable contact is electrically isolated from a drive shaft passing through the through hole. The peripheral wall of the insulating member increases a creepage distance between the drive shaft passing through the through hole and the exposed portion of the movable contact.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Chinese Patent Application No. CN202210858080.9 filed on Jul. 20, 2022, in the State Intellectual Property Office of China, the whole disclosure of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a movable contact module of a contactor, a movable contact assembly of a contactor comprising the movable contact module, a movable contact device of a contactor including the contactor movable contact assembly, and a contactor including the contactor movable contact device.

BACKGROUND

A contactor typically includes a housing, a movable contact, a static contact, a drive shaft, a coil, a magnetic core, and a magnetic conductive component. The static contact, coil, and magnetic conductive component are fixedly arranged in the housing. The movable contact, drive shaft, and magnetic core are movably arranged in the housing. When the coil is energized, it generates a magnetic field, which produces electromagnetic force on the drive shaft and magnetic core. Under the action of the electromagnetic force, the drive shaft drives the movable contact to move to a closed position in contact with the static contact. When the coil is deenergized, the magnetic field and electromagnetic force cease, and the drive shaft drives the movable contact to an opened position separated from the static contact under the action of the return spring.

In applications without insulation isolation requirements, the drive shaft is usually directly connected to the movable contact. For applications with insulation isolation requirements, safety standards require that the coil circuit and contact circuit meet certain insulation distance requirements. However, in existing applications, the creepage distance between the movable contact and the drive shaft (i.e., the shortest distance along a surface of a solid insulating material between the movable contact and the drive shaft) is relatively short, which does not meet the requirements for high-voltage isolation.

In addition, in the prior art, in order to detect the state of the main contact, it is necessary to provide an auxiliary switch and an auxiliary switch pressing portion. The auxiliary switch pressing portion is usually connected to the drive shaft and moves synchronously therewith. When the drive shaft drives the movable contact to the closed position, the auxiliary switch pressing portion presses the auxiliary switch to trigger the auxiliary switch. When the drive shaft drives the movable contact to the opened position, the auxiliary switch pressing portion is separated from the auxiliary switch to release the auxiliary switch and restore the auxiliary switch to its initial state. Therefore, the position of the movable contact can be determined based on the state of the auxiliary switch. That is, when the auxiliary switch is in the triggered state, it is determined that the movable contact is in the closed position. When the auxiliary switch is in the initial state, it is determined that the movable contact is still in the opened position. However, due to the elastic connection between the movable contact and the drive shaft, the drive shaft can move an overtravel amount relative to the movable contact. Therefore, when the movable and static contacts cannot be separated from each other due to fusion or other fault conditions, the drive shaft can still be moved by an overstroke or overtravel distance under the action of the spring. This may cause the auxiliary switch pressing portion to release the auxiliary switch, resulting in the auxiliary switch returning to its initial state. Therefore, in prior art devices, there is uncertainty in determining whether the movable contact has fusion or other faults based on the state of the auxiliary switch, which affects the safety of use.

SUMMARY

According to an embodiment of the present disclosure, a movable contact module for a contactor comprises an insulating member and a movable contact. The insulating member includes an insulating body having a through hole, and a peripheral wall protruding from the insulating body and surrounding an opening of the through hole. The movable contact has a fixed portion fixed in the insulating body, and an exposed portion exposed from the insulating body. The fixed portion of the movable contact is surrounded by the insulating body so that the movable contact is electrically isolated from a drive shaft passing through the through hole. The peripheral wall of the insulating member increases the creepage distance between the drive shaft passing through the through hole and the exposed portion of the movable contact.

DETAILED DESCRIPTION OF THE EMBODIMENTS

According to an embodiment of the present invention, a movable contact module of a contactor includes an insulating member comprising an insulating body and a through hole penetrating through the insulating body, and a movable contact comprising a fixed portion fixed in the insulating body and an exposed portion exposed from the insulating body. The fixed portion of the movable contact is wrapped in the insulating body so that the movable contact is electrically isolated from a drive shaft passing through the through hole. The insulating member further includes a peripheral wall protruding from the insulating body and surrounding an opening of the through hole. The peripheral wall increasing the creepage distance between the drive shaft passing through the through hole and the exposed portion of the movable contact.

According to another embodiment the present invention, there is provided a movable contact assembly for a contactor. The movable contact assembly comprises the above movable contact module, and a drive shaft which passes through a through hole in the insulating member. The drive shaft is elastically connected to the contactor movable contact module for driving the movable contact to move between a closed position in electrical contact with a static contact and an opened position in electrical separation from the static contact.

According to another embodiment of the present invention, there is provided a movable contact device for contactor. The movable contact device comprises the above movable contact assembly, a magnetic core, a magnetic conductive plate located above the magnetic core, a second spring compressed between the magnetic conductive plate and the magnetic core, and a second snap ring. The second snap ring which is snapped on the other end of the drive shaft and rests against the bottom surface of the magnetic core. The drive shaft passes through the magnetic core, the magnetic conductive plate, and the second spring, and a second snap groove for snapping the second snap ring is formed on the other end of the drive shaft.

According to another embodiment the present invention a contactor comprises a housing, the above movable contact device which is installed in the housing, a coil arranged in the housing, and a static contact arranged in the housing. The magnetic core is housed in the coil and movable relative to the housing, and the magnetic conductive plate is fixed to the housing. When the coil is energized, the drive shaft drives the movable contact to a closed position in electrical contact with the static contact under the action of electromagnetic force generated by the coil. When the coil is deenergized, the drive shaft drives the movable contact to an opened position electrically separated from the static contact under the reset force of the second spring.

FIG.1shows an illustrative perspective view of the contactor movable contact module according to an exemplary embodiment of the present invention when viewed from the front side.FIG.2shows an illustrative perspective view of the contactor movable contact module10according to an exemplary embodiment of the present invention when viewed from the rear side.FIG.3shows a cross-sectional view of the contactor movable contact module10according to an exemplary embodiment of the present invention.

As shown inFIGS.1-3, in the illustrated embodiment, the contactor movable contact module10includes a movable contact11and an insulating member12. The insulating member12includes an insulating body120and a through hole102penetrating through the insulating body. The movable contact11includes a fixed portion110fixed in the insulating body120and an exposed portion111exposed from the insulating body. The fixed portion110of the movable contact11is wrapped in or surrounded by the insulating body120so that the movable contact is electrically isolated from a drive shaft13(seeFIGS.4and5) passing through the through hole102. The insulating member12also includes peripheral walls121,122, and124protruding from the insulating body120and surrounding an opening of the through hole102to increase the creepage distance between the drive shaft13passing through the through hole and the exposed portion111of the movable contact11(i.e., the shortest distance along a surface of the insulating member12between the movable contact11and the drive shaft13).

The insulating body120has opposite top and bottom surfaces in its thickness direction. The peripheral walls121,122, and124include a first peripheral wall121and a second peripheral wall122,124. The first peripheral wall121protrudes from the top surface of the insulating body120and surrounds the top opening of the through hole102. The second peripheral wall122,124protrudes from the bottom surface of the insulating body120and surrounds the bottom opening of the through hole102.

The insulating body120has opposite left and right sides in its longitudinal direction. Two end portions111of the movable contact11are exposed from the left and right sides of the insulating body, respectively. The insulating member12further includes a plurality of isolation walls123protruding from the top surface of the insulating body120. The plurality of isolation walls123are located on both radial sides of the through hole102. The isolation walls123extend along the width and thickness directions of the insulating body120to further increase the creepage distance between the drive shaft13passing through the through hole102and the exposed end(s)111of the movable contact11. The isolation walls123are located in an inner cavity surrounded by the first peripheral wall121and are separated from the first peripheral wall in a radial direction of the through hole102. The insulating member12also includes connecting walls123a connected between the isolation walls123and the first peripheral wall121, as shown inFIG.1.

Still referring toFIGS.1to3, the insulating body120has opposite front and rear sides in its width direction, and an opening is formed on the first peripheral wall121that opens towards the front side of the insulating body. The insulating member12also includes at least one pair of side walls125connected to both sides of the opening of the first peripheral wall121, which extend along the thickness and width directions of the insulating body120to further increase the creepage distance between the drive shaft13passing through the through hole102and the exposed end111of the movable contact11. The side wall125extends from the first peripheral wall121to the bottom surface of the insulating body120and is connected to the front side of the insulating body120.

The second peripheral walls122,124include a second inner peripheral wall124and a second outer peripheral wall122. The second inner peripheral wall124protrudes from the bottom surface of the insulating body120and surrounds the bottom opening of the through hole102. The second outer peripheral wall122protrudes from the bottom surface of the insulating body120and surrounds the second inner peripheral wall124. The second outer peripheral wall122and the second inner peripheral wall124are spaced apart in a radial direction of the through hole102and extend along the circumferential and axial directions of the through hole to increase the creepage distance between the drive shaft13passing through the through hole102and the exposed end111of the movable contact11. An extension height of the second inner peripheral wall124in the axial direction of the through hole102is greater than the extension height of the second outer peripheral wall122in the axial direction of the through hole102.

The second inner peripheral wall124extends continuously along the circumferential direction of the through hole102. Specifically, the second inner peripheral wall124is a continuous peripheral wall without any opening. An opening is formed on the second outer peripheral wall122that opens towards the front side of the insulating body120. However, the present invention is not limited to the illustrated embodiment, and the second outer peripheral wall122may also be a continuous peripheral wall without any opening.

In the illustrated embodiment, the insulating member12also includes an auxiliary switch pressing portion126for triggering an auxiliary switch60, so that the auxiliary switch pressing portion126moves synchronously with the movable contact11. Further, the insulating member12and the movable contact11are formed into an integral injection molded piece, in which the movable contact11is an insert and the insulating member12is an injection molded part, such that the insulating member12and the movable contact11are directly bonded together.

FIG.4shows an illustrative perspective view of a contactor movable contact assembly according to an exemplary embodiment of the present invention when viewed from the front side.FIG.5shows a cross-sectional view of a contactor movable contact assembly according to an exemplary embodiment of the present invention.

As shown inFIGS.1-5, the contactor movable contact assembly includes the aforementioned contactor movable contact module10and the drive shaft13. The drive shaft13passes through the through hole102in the insulating member12. The drive shaft13is elastically connected to the contactor movable contact module10for driving the movable contact11to move between a closed position in electrical contact with a static contact (not shown) and an opened position in electrical separation from the static contact.

In the illustrated embodiment, a radial flange13aand a first snap groove13c are formed on the drive shaft13. The first snap groove13cis located at one end133of the drive shaft13. The contactor movable contact assembly further includes a first snap ring134and a first spring135. The first snap ring134is snapped in the first snap groove13c and rests against the top surface of the insulating body120. The first spring135is compressed between the bottom surface of the insulating body120and the radial flange13aof the drive shaft13.

The contactor movable contact assembly further includes a first washer131and a second washer132. The first washer131is supported on the radial flange13a of the drive shaft13. The second washer132is against the bottom surface of the insulating body120. The two ends of the first spring135rest against the first washer131and the second washer132, respectively. The first spring135is accommodated in an inner cavity surrounded by the second inner peripheral wall124of the insulating member12to position the first spring135in a circumferential direction. The first spring135is used to provide contact pressure to the movable contact11to ensure reliable electrical contact between the movable contact11and the static contact.

FIG.6shows an illustrative perspective view of a contactor movable contact device according to an exemplary embodiment of the present invention when viewed from the front side.FIG.7shows a cross-sectional view of a contactor movable contact device according to an exemplary embodiment of the present invention.FIG.8shows an illustrative perspective view of a contactor movable contact device according to an exemplary embodiment of the present invention when viewed from the rear.

As shown inFIGS.1-8, the contactor movable contact device includes the aforementioned contactor movable contact assembly, a magnetic core30, a magnetic conductive plate40, a second spring138, and a second snap ring137. The magnetic conductive plate40is located above the magnetic core30. The second spring138is compressed between the magnetic conductive plate40and the magnetic core30. The second snap ring137is snapped on the other end of the drive shaft13and rests against the bottom surface of the magnetic core30. The drive shaft13passes through the magnetic core30, the magnetic conductive plate40, and the second spring138. A second snap groove13b for holding the second snap ring137is formed on the other end136of the drive shaft13.

The contactor movable contact device further comprises an insulation mounting piece50and an auxiliary switch60. The insulation mounting piece50is mounted on the top surface of the magnetic conductive plate40. The auxiliary switch60is mounted on the insulation mounting piece When the movable contact11is moved to the closed position in electrical contact with the static contact, the auxiliary switch pressing portion126on the insulating member12presses a triggering portion61of the auxiliary switch60to trigger the auxiliary switch60, causing the auxiliary switch60to be switched to a triggering state. When the movable contact11is moved to the opened position electrically separated from the static contact, the auxiliary switch pressing portion126on the insulating member12is separated from the auxiliary switch60to release the auxiliary switch60, and the auxiliary switch60is reset to its initial state.

The insulation mounting piece50includes a base plate51and a bracket52. The base plate51is mounted on the top surface of the magnetic conductive plate40. The bracket52is connected to the base plate51. The contactor movable contact device further comprises a circuit board70fixed to the bracket52, and the auxiliary switch60is mounted on the circuit board70.

In an exemplary embodiment of the present invention, a contactor is also disclosed. The contactor comprises a housing, the aforementioned contactor movable contact device, a coil, and a static contact. The contactor movable contact device is installed in the housing. The coil and the static contact are fixedly arranged in the housing. The magnetic core30is housed in the coil and movable relative to the housing, and the magnetic conductive plate40is fixed to the housing. When the coil is energized, the drive shaft13drives the movable contact11to the closed position in electrical contact with the static contact under the action of electromagnetic force generated by the coil. When the coil is deenergized, the drive shaft13drives the movable contact11to the opened position electrically separated from the static contact under the reset force of the second spring138.

In addition, those areas in which it is believed that those of ordinary skill in the art are familiar, have not been described herein in order not to unnecessarily obscure the invention described. Accordingly, it has to be understood that the invention is not to be limited by the specific illustrative embodiments, but only by the scope of the appended claims.