CN220933993U - Contact device and switching device - Google Patents

Abstract

The utility model belongs to the technical field of piezoelectric devices, and discloses a contact device and a switching device. The contact device comprises a fixed contact assembly and a movable contact assembly, wherein the fixed contact assembly comprises a fixed contact plate and a fixed contact, and the fixed contact is arranged on the fixed contact plate. The moving contact assembly comprises a moving contact bridge, a moving contact, a magnetic yoke and an armature, wherein the moving contact is arranged at the end part of the moving contact bridge, the moving contact can be in contact conduction with the fixed contact, the armature is sleeved on the moving contact bridge and extends towards the magnetic yoke, and when the moving contact and the fixed contact are separated, the armature is abutted to the magnetic yoke, so that the armature and the magnetic yoke form a magnetic path closed loop. The contact device can effectively prolong the return time of the moving contact, prevent the contact from reburning and breaking down, and improve the use safety of the contact device and the switching device.

Description

Contact device and switching device

Technical Field

The utility model relates to the technical field of piezoelectric devices, in particular to a contact device and a switching device.

Background

The contact device is an essential component of the switching device and is used for switching on, carrying and breaking the current flowing in the main loop when the switching device works. The switching devices including these contact devices include circuit breakers, contactors, intermediate relays, motor starters, and the like. In general, the above-described switching devices include one or more moving contacts and associated one or more stationary contacts. The movable contact and the stationary contact are engaged during normal operation to complete a current carrying path through the switching device. The moving and stationary contacts are separated in the event of an overload of the current, thermal protection or other undesired event, and a loss of coil voltage of the shut-off circuit breaker, intermediate relay or contactor.

Arcing occurs when the contacts separate, which if not dissipated, extinguished or quenched quickly, will cause damage to the contacts, the device itself or the load being protected. In the contact device in the prior art, after the contact is separated, the return time of the moving contact is too short, the moving contact contacts with the fixed contact or reaches a breakdown distance, a reburning phenomenon is easy to generate, effective arc extinction cannot be caused, even explosion conditions can be generated due to serious reburning, and the use safety of a switching electric appliance is seriously threatened.

Accordingly, improvements in contact arrangements and switching devices are needed to address the above issues.

Disclosure of utility model

The utility model aims to provide a contact device and a switching device, which can effectively prolong the return time of a moving contact, prevent the reburning breakdown of the contact and improve the use safety of the contact device and the switching device.

To achieve the purpose, the utility model adopts the following technical scheme:

A contact arrangement comprising:

The static contact assembly comprises a static contact plate and a static contact, wherein the static contact is arranged on the static contact plate;

The movable contact assembly comprises a movable contact bridge, a movable contact, a magnetic yoke and an armature, wherein the movable contact is arranged at the end part of the movable contact bridge, the movable contact can be in contact conduction with the fixed contact, the armature is sleeved on the movable contact bridge and extends towards the magnetic yoke, and when the movable contact and the fixed contact are repelled, the armature is abutted to the magnetic yoke, so that the armature and the magnetic yoke form a magnetic path closed loop.

As an alternative, the armature includes an abutting portion and two extending portions, the abutting portion is attached to one side of the movable contact bridge, which faces away from the magnetic yoke, and the two extending portions are respectively connected to two sides of the abutting portion, and are attached to the side of the movable contact bridge, which extends toward the magnetic yoke.

Alternatively, the extending portion includes two extending plates disposed at intervals, and the two extending plates are respectively connected to two ends of the abutting portion.

As an alternative, the moving contact assembly further includes an elastic member, where the elastic member is disposed between the yoke and the moving contact bridge, and the elastic member can apply an elastic force to the moving contact bridge, so that the moving contact bridge moves toward the fixed contact, and the moving contact is in contact conduction with the fixed contact.

As an alternative scheme, the movable contact bridge is provided with a limiting protrusion towards one side of the magnetic yoke, the elastic piece is sleeved on the limiting protrusion, and the limiting protrusion is used for limiting the elastic piece to swing.

As an alternative scheme, be provided with the U type hole on the static contact board, at least some electric current flow direction around the U type hole is opposite with the electric current flow direction in the movable contact bridge, the static contact is connected in by the U type hole encloses the static contact board department of establishing.

As an alternative, the static contact plate includes a first contact plate, two second contact plates and a third contact plate, the first contact plate, the two second contact plates and the third contact plate are arranged around the U-shaped hole, one end of the first contact plate is a terminal, the other end of the first contact plate extends to the bottom side of the U-shaped hole, the second contact plate is connected with the first contact plate, the second contact plate is connected with the third contact plate and the first contact plate, current flows into the static contact through the first contact plate, the two second contact plates and the third contact plate in sequence, current in the moving contact assembly flows towards the center of the moving contact bridge through the moving contact and the moving contact bridge, and current in the second contact plate flows towards the center of the moving contact bridge opposite to current in the moving contact bridge.

Alternatively, the distance between the movable contact bridge and the static contact plate is gradually increased outwards from the contact position of the movable contact and the static contact.

The switching device comprises the contact device, and further comprises an arc extinguishing chamber, wherein one arc extinguishing chamber is arranged at each of two ends of the movable contact bridge, and an arc generated by separating the movable contact from the fixed contact is led into the arc extinguishing chamber.

As an alternative scheme, the switching device further comprises an arc striking plate, the arc striking plate is connected with the two arc extinguishing chambers, and the magnetic yoke is arranged on the arc striking plate.

The beneficial effects are that:

According to the contact device provided by the utility model, the armature is sleeved on the movable contact bridge and extends towards the magnetic yoke, the armature and the magnetic yoke form the electromagnetic loop, the electromagnetic loop encases the movable contact bridge, short-circuit current in the movable contact bridge can be induced in real time, and when a magnetic field generated by the short-circuit current in the movable contact bridge exceeds a certain value, the force generated by the magnetic field tends to drive the movable contact bridge to move towards the direction close to the magnetic yoke. Meanwhile, due to the action of electric repulsive force, the movable contact bridge moves to form a magnetic path closed loop with the armature and the magnetic yoke to generate a closed magnetic loop, and at the moment, the magnetic force generated by the magnetic field can offset the rebound reset force of part of movable contacts to the fixed contacts, so that the reset time of the movable contact bridge is prolonged, the time of large opening distance between the movable contacts and the fixed contacts is prolonged, breakdown and reburning between the contacts are avoided, and the arc extinguishing capability is improved.

Drawings

Fig. 1 is a schematic diagram of a sectional structure of a switching device according to an embodiment of the present utility model;

fig. 2 is a schematic cross-sectional structure of a moving contact assembly according to an embodiment of the present utility model;

fig. 3 is a schematic perspective view of a moving contact assembly according to an embodiment of the present utility model;

Fig. 4 is a schematic perspective view of a static contact assembly according to an embodiment of the present utility model;

Fig. 5 is a schematic diagram of current flow in a static contact plate and a dynamic contact bridge according to an embodiment of the present utility model.

In the figure:

1. A stationary contact assembly; 11. a stationary touch plate; 110. a U-shaped hole; 111. a first contact plate; 112. a second contact plate; 113. a third contact plate; 12. a stationary contact;

2. A moving contact assembly; 21. a movable contact bridge; 211. a limit protrusion; 22. a moving contact; 23. a yoke; 24. an armature; 241. an abutting portion; 242. an extension; 2421. an extension plate; 25. an elastic member;

3. An arc extinguishing chamber;

4. An arc striking plate;

5. A base;

6. and a contact support.

Detailed Description

The utility model is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting thereof. It should be further noted that, for convenience of description, only some, but not all of the structures related to the present utility model are shown in the drawings.

In the description of the present utility model, unless explicitly stated and limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

In the present utility model, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "left", "right", and the like are orientation or positional relationships based on those shown in the drawings, merely for convenience of description and simplicity of operation, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the utility model. Furthermore, the terms "first," "second," and the like, are used merely for distinguishing between descriptions and not for distinguishing between them.

As shown in fig. 1, the present embodiment provides a switching device, which may be specifically a circuit breaker, a contactor, an intermediate relay, a motor starter, or the like. The switching device comprises a shell, arc-extinguishing chambers 3 and contact devices, wherein the arc-extinguishing chambers 3 and the contact devices are arranged in the shell, the two arc-extinguishing chambers 3 are arranged on two sides of the contact devices respectively, and an electric arc generated by the contact devices is led into the arc-extinguishing chambers 3 for arc extinction.

The switch electrical apparatus still includes the striking board 4, and striking board 4 sets up on the base 5 of casing, and two explosion chambers 3 are connected to striking board 4, and contact device sets up on striking board 4. By arranging the arc striking plate 4, the two arc extinguishing chambers 3 are connected in series, which is beneficial to improving the arc voltage.

The contact arrangement comprises a moving contact 22 and a stationary contact 12, the moving contact 22 and the stationary contact 12 being engaged during normal operation to complete a current carrying path through the switching device. The moving contact 22 and the stationary contact 12 are separated in the event of a current overload, thermal protection or other undesired event, and a coil voltage outage of the switching device being turned off.

Arcing occurs when the contacts separate, which if not dissipated, extinguished or quenched quickly, will cause damage to the contacts, the device itself or the load being protected. In the contact device in the prior art, after the contact is separated, the return time of the moving contact 22 is too short, the moving contact 22 contacts with the fixed contact 12 or reaches a breakdown distance, a re-burning phenomenon is easy to generate, so that effective arc extinction cannot be realized, severe re-burning and even explosion conditions can be generated, and the use safety of a switching apparatus is seriously threatened.

In order to solve the above problems, in this embodiment, the contact device is improved to prolong the reset time after the contacts are separated, and avoid breakdown and reburning between the contacts.

Specifically, as shown in fig. 1-3, the contact device comprises a fixed contact assembly 1 and a movable contact assembly 2, wherein the fixed contact assembly 1 comprises a fixed contact plate 11 and a fixed contact 12, and the fixed contact 12 is arranged on the fixed contact plate 11. The moving contact assembly 2 comprises a moving contact bridge 21, a moving contact 22, a magnetic yoke 23 and an armature 24, wherein the moving contact 22 is arranged at the end part of the moving contact bridge 21, the moving contact 22 can be in contact conduction with the fixed contact 12, the armature 24 is sleeved on the moving contact bridge 21 and extends towards the magnetic yoke 23, and when the moving contact 22 and the fixed contact 12 are separated, the armature 24 is abutted against the magnetic yoke 23, so that the armature 24 and the magnetic yoke 23 form a magnetic path closed loop.

By arranging the armature 24 to be sleeved on the movable contact bridge 21 and extend towards the direction of the magnetic yoke 23, the armature 24 and the magnetic yoke 23 form an electromagnetic loop, the electromagnetic loop encases the movable contact bridge 21, short-circuit current in the movable contact bridge 21 can be immediately sensed, and when a magnetic field generated by the short-circuit current in the movable contact bridge 21 exceeds a certain value, the force generated by the magnetic field tends to drive the movable contact bridge 21 to move towards the direction close to the magnetic yoke 23. Meanwhile, due to the action of electric repulsive force, the movable contact bridge 21 moves to form a magnetic circuit closed loop with the armature 24 and the magnetic yoke 23, so that a closed magnetic circuit is generated. At this time, the magnetic force generated by the magnetic field can offset the reset force of the partial transfer contact 22 to the fixed contact 12, prolong the reset time of the movable contact bridge 21, increase the time of large opening distance between the movable contact 22 and the fixed contact 12, avoid breakdown and reburning between the contacts, and improve the arc extinguishing capability.

Further, as shown in fig. 1, the distance between the movable contact bridge 21 and the stationary contact plate 11 gradually increases from the contact position of the movable contact 22 and the stationary contact 12. That is, a bell mouth shape toward the arc extinguishing chamber 3 is formed between the movable contact bridge 21 and the stationary contact plate 11, thereby more facilitating the introduction of the arc between the contacts into the arc extinguishing chamber 3.

In this embodiment, two ends of the movable contact bridge 21 are respectively provided with a movable contact 22, the two movable contacts 22 respectively correspond to the arc extinguishing chambers 3 on two sides, and an arc generated by separating the movable contact 22 from the fixed contact 12 is introduced into the arc extinguishing chambers 3.

Further, as shown in fig. 3, the armature 24 includes an abutting portion 241 and two extending portions 242, the abutting portion 241 is attached to one side of the movable contact bridge 21 away from the yoke 23, and the two extending portions 242 are respectively connected to two sides of the abutting portion 241 and extend in a direction toward the yoke 23 along a side surface of the movable contact bridge 21. The abutting part 241 and the two extending parts 242 form a U-shaped structure, and cover three sides of the movable contact bridge 21, so that the armature 24 and the magnetic yoke 23 form a magnetic system loop.

Alternatively, as shown in fig. 3, the extension portion 242 includes two extension plates 2421 disposed at intervals, and the two extension plates 2421 are respectively connected to two ends of the abutting portion 241. When the armature 24 moves toward the yoke 23, the four extension plates 2421 are respectively abutted against four corners of the square yoke 23.

Further, as shown in fig. 3, the moving contact assembly 2 further includes an elastic member 25, where the elastic member 25 is disposed between the yoke 23 and the moving contact bridge 21, and the elastic member 25 can apply an elastic force to the moving contact bridge 21, so that the moving contact bridge 21 moves toward the fixed contact 12 to make the moving contact 22 contact and conduct with the fixed contact 12. The elastic member 25 is disposed at a middle position of the movable contact bridge 21, so that the two movable contacts 22 are symmetrically distributed with respect to the elastic member 25. The elastic member 25 may employ a spring.

Under the condition that the switching device is normally switched on, the movable contact bridge 21 moves towards the direction of the fixed contact 12 under the elastic force of the elastic piece 25, so that the movable contact 22 is in contact with the fixed contact 12, and electrification is realized. When the switching device is normally disconnected, an operating mechanism (not shown in the figure) presses down the contact support piece 6, overcomes the elastic force of the elastic piece 25, pushes the movable contact bridge 21 to move in a direction away from the fixed contact 12, and separates the movable contact 22 from the fixed contact 12. When the switching device is short-circuited, the moving contact 22 and the fixed contact 12 are repelled by the elastic force of the elastic member 25 under the action of electric repulsive force. It should be noted that, the operating mechanism and the contact support 6 are conventional structures in the switching apparatus, and specific structures, connection manners, working principles and the like thereof are not described in detail herein.

Optionally, as shown in fig. 3, a limiting protrusion 211 is disposed on a side of the movable contact bridge 21 facing the magnetic yoke 23, and the elastic member 25 is sleeved on the limiting protrusion 211, where the limiting protrusion 211 is used for limiting the swing of the elastic member 25, so that the elastic member 25 is stably installed.

In the prior art, when a short circuit occurs in a switching electric appliance, an electric repulsive force for separating a moving contact 22 from a fixed contact 12 is insufficient, so that the moving contact 22 has long dead time and small distance after short circuit, and the risk of breakdown and reburning between the contacts is high.

In order to solve the above problems, the static contact assembly 1 is further improved in this embodiment, so as to further improve the short-circuit breaking capability of the contact device. Specifically, as shown in fig. 4 and 5, the stationary contact 11 is provided with a U-shaped hole 110, and at least part of the current around the U-shaped hole 110 flows in the opposite direction to the current in the movable contact bridge 21, and the stationary contact 12 is connected to the stationary contact 11 surrounded by the U-shaped hole 110.

Through setting up U type hole 110 on static contact 11 to connect static contact 12 in the static contact 11 department of being enclosed by U type hole 110, 90 turn to takes place when making the electric current in the static contact 11 flow to static contact 12, appear in the static contact 11 with the electric current that flows in the movable contact bridge 21 opposite direction, realize the increase of the lorentmagnetic force that the electric current interact produced in the conductive loop, namely electric repulsion's increase, the repulsion dead time after the movable contact bridge 21 takes place the short circuit has been reduced, the breaking start action current of movable contact 22 reduces, the current limiting capability has been improved, the electric repulsion between the contact has been increased simultaneously, the repulsion distance of movable contact bridge 21 has been increased, be favorable to increasing electric arc voltage.

Specifically, as shown in fig. 3 and 4, the stationary contact plate 11 includes a first contact plate 111, two second contact plates 112 and a third contact plate 113, the first contact plate 111, the two second contact plates 112 and the third contact plate 113 are disposed around the U-shaped hole 110, one end of the first contact plate 111 is a terminal, the other end of the first contact plate 111 extends to the bottom side of the U-shaped hole 110, the second contact plate 112 connects the third contact plate 113 and the first contact plate 111, the third contact plate 113 is located between the two second contact plates 112, current flows into the stationary contact 12 through the first contact plate 111, the two second contact plates 112 and the third contact plate 113 in sequence, the current in the movable contact assembly 2 flows toward the center of the movable contact bridge 21 through the movable contact 22 and the movable contact bridge 21, and the current in the second contact plate 112 flows opposite to the current in the movable contact bridge 21. The current flow in the second contact plate 112 is shown by arrow a in fig. 5 and the current flow in the movable contact bridge 21 is shown by arrow b in fig. 5.

It is to be understood that the above examples of the present utility model are provided for clarity of illustration only and are not limiting of the embodiments of the present utility model. Various obvious changes, rearrangements and substitutions can be made by those skilled in the art without departing from the scope of the utility model. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the utility model are desired to be protected by the following claims.

Claims (10)

1. A contact arrangement, comprising:

The static contact assembly (1) comprises a static contact plate (11) and a static contact (12), wherein the static contact (12) is arranged on the static contact plate (11);

The movable contact assembly (2) comprises a movable contact bridge (21), a movable contact (22), a magnetic yoke (23) and an armature (24), wherein the movable contact (22) is arranged at the end part of the movable contact bridge (21), the movable contact (22) can be in contact conduction with the fixed contact (12), the armature (24) is sleeved on the movable contact bridge (21) and extends towards the magnetic yoke (23), and when the movable contact (22) and the fixed contact (12) are repelled, the armature (24) is abutted to the magnetic yoke (23), so that the armature (24) and the magnetic yoke (23) form a magnetic circuit closed loop.

2. The contact device according to claim 1, wherein the armature (24) comprises an abutting portion (241) and two extending portions (242), the abutting portion (241) is attached to one side of the movable contact bridge (21) facing away from the magnetic yoke (23), and the two extending portions (242) are respectively connected to two sides of the abutting portion (241) and extend in a direction facing the magnetic yoke (23) while attaching to the side of the movable contact bridge (21).

3. The contact device according to claim 2, wherein the extension portion (242) comprises two extension plates (2421) arranged at intervals, and the two extension plates (2421) are respectively connected to both ends of the abutting portion (241).

4. The contact device according to claim 1, wherein the movable contact assembly (2) further comprises an elastic member (25), the elastic member (25) is disposed between the yoke (23) and the movable contact bridge (21), and the elastic member (25) can apply an elastic force to the movable contact bridge (21) so as to move the movable contact bridge (21) toward the fixed contact (12) to bring the movable contact (22) into contact conduction with the fixed contact (12).

5. The contact device according to claim 4, wherein a limit protrusion (211) is provided on a side of the movable contact bridge (21) facing the yoke (23), and the elastic member (25) is sleeved on the limit protrusion (211).

6. Contact arrangement according to claim 1, characterized in that the stationary contact plate (11) is provided with a U-shaped hole (110), at least part of the current flow around the U-shaped hole (110) being counter to the current flow in the movable contact bridge (21), the stationary contact (12) being connected to the stationary contact plate (11) enclosed by the U-shaped hole (110).

7. The contact arrangement according to claim 6, characterized in that the stationary contact plate (11) comprises a first contact plate (111), two second contact plates (112) and a third contact plate (113), the first contact plate (111), the two second contact plates (112) and the third contact plate (113) being arranged around the U-shaped hole (110), one end of the first contact plate (111) being a terminal, the other end of the first contact plate (111) extending to the bottom side of the U-shaped hole (110), the second contact plate (112) being connected to the first contact plate (111), the second contact plate (112) connecting the third contact plate (113) and the first contact plate (111), the current flowing through the first contact plate (111), the two second contact plates (112) and the third contact plate (113) in turn into the stationary contact (12), the current flowing through the moving contact (22) in the moving contact assembly (2) and through the moving bridge (21) flowing in the opposite direction to the moving bridge (21).

8. Contact arrangement according to any one of claims 1-7, characterized in that the distance between the movable contact bridge (21) and the stationary contact plate (11) increases gradually outwards from the contact position of the movable contact (22) with the stationary contact (12).

9. Switching device, characterized in that it comprises a contact device according to any one of claims 1-8, and further comprises an arc extinguishing chamber (3), wherein one arc extinguishing chamber (3) is arranged at each of the two ends of the movable contact bridge (21), and an arc generated by separating the movable contact (22) from the fixed contact (12) is introduced into the arc extinguishing chamber (3).

10. Switching device according to claim 9, characterized in that it further comprises an arc striking plate (4), said arc striking plate (4) being connected to two of said arc extinguishing chambers (3), said yoke (23) being arranged on said arc striking plate (4).