CN217691031U - Circuit breaker tripping device - Google Patents

Abstract

A circuit breaker tripping device belongs to the technical field of low-voltage electrical appliances. Including conductor, bimetallic strip and electro-magnet, the lower extreme and the conductor fixed connection of bimetallic strip, the upper end constitutes to actuate the free end that the circuit breaker tripped when the circuit transships, the electro-magnet include fixed part of fixed mounting and the armature as the movable part, wherein: a gap exists between the fixing portion and the conductor. The advantages are that: the fixing part which can obstruct the electromagnet absorbs the heat of the current-carrying conductor to ensure the heating of the bimetallic strip by the conductor, so that the bimetallic strip can be rapidly heated, the reliability of the tripping action can be ensured, and the structure is simple.

Description

Circuit breaker tripping device

Technical Field

The utility model belongs to the technical field of low-voltage apparatus, concretely relates to circuit breaker trip gear.

Background

The tripping device is an important part of the circuit breaker, is arranged in a circuit breaker base, and can act to unlock the operating mechanism when fault current occurs in a circuit, and the operating mechanism drives the movable guide rod to perform opening operation to break the circuit, thereby playing a role in protecting the circuit. The circuit breaker tripping device comprises an electromagnetic tripping device, a thermomagnetic tripping device, a shunt tripping device, an undervoltage tripping device and the like. The thermomagnetic trip device generally comprises two action parts, namely a bimetallic strip and an electromagnet, wherein the bimetallic strip is riveted and fixed on a conductive loop and absorbs heat from the conductive loop; the electromagnet comprises a fixed part and a movable part, for example, the 'circuit breaker tripping device' introduced in the Chinese utility model patent publication No. CN201796836U, wherein the fixed part comprises a yoke and a bracket, the yoke and the bracket are fixed with each other, and the fixed part is fixed on the conductive loop through the fixation of the yoke or the bracket and the conductive loop. As shown in fig. 1, the movable part of the electromagnet 3 is an armature, which is pivoted on the bracket, and when a short-circuit large current occurs in the circuit, the electromagnet 3 acts to push the circuit breaker operating mechanism to unlock. For space saving, the fixing portions of the bimetal 2 and the electromagnet 3 are arranged on both sides of the conductor 1 at the same position in the conductive circuit and are in contact with the conductor 1. When a large overload current occurs, the bimetallic strip 2 is required to act quickly, but in the structure, because the yoke of the electromagnet 3 is made of ferromagnetic material and the support is made of metal material, the yoke and the support have strong heat-conducting property and large heat capacity, when the overload current occurs in the conductive loop, the heat of the conductor can be absorbed, so that the temperature rise time of the bimetallic strip 2 is obviously prolonged, the opening action time of the circuit breaker is further influenced, and the fault current in the circuit cannot be cut off timely.

In view of the above-mentioned prior art, there is a need for an improved structure of the tripping device of the prior art circuit breaker, for which reason the applicant has made an advantageous design, and the technical solutions to be described below have been created in this context.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a circuit breaker trip gear, its action reliability is high and simple structure.

The utility model aims at reaching like this, a circuit breaker trip gear, including conductor, bimetallic strip and electro-magnet, the lower extreme and the conductor fixed connection of bimetallic strip, the upper end constitutes for the free end that actuates the circuit breaker dropout when the circuit transships, the electro-magnet include fixed mounting's fixed part and the armature as the movable part, there is the clearance between fixed part and the conductor.

In a specific embodiment of the present invention, the fixing portion has a U-shaped cross-section, the armature is pivotally mounted on the fixing portion, and the conductor passes through the U-shaped cavity of the fixing portion and is spaced apart from the fixing portion to form the gap.

In another specific embodiment of the present invention, the gap is provided with a heat insulation paper board.

In another specific embodiment of the present invention, the fixing portion includes a yoke and a bracket, the yoke includes a yoke bottom plate and a pair of yoke side plates formed by bending two sides of the yoke bottom plate, the bracket includes a bracket bottom plate fixed to the yoke bottom plate in an overlapping manner and a bracket side plate extending from the bracket bottom plate, and the armature is pivoted on the bracket side plate and correspondingly engaged with the pair of yoke side plates.

In another specific embodiment of the present invention, the heat insulation paper board is located between the conductor and the yoke base plate, the heat insulation paper board, the conductor and the bimetal are riveted and fixed in sequence by rivets.

In still another specific embodiment of the present invention, the heat insulation paper board is located between the conductor and the support base plate, the heat insulation paper board, the conductor and the bimetal are riveted and fixed in sequence by rivets.

In yet another specific embodiment of the present invention, the conductor and the fixing portion are fixed to the circuit breaker base, respectively.

The utility model discloses a set up the clearance between the fixed part of electro-magnet and conductor to further set up thermal-insulated cardboard, compare with prior art, the beneficial effect who has is: the fixing part which can obstruct the electromagnet absorbs the heat of the current-carrying conductor to ensure the heating of the bimetallic strip by the conductor, so that the bimetallic strip can be rapidly heated, the reliability of the tripping action can be ensured, and the structure is simple.

Drawings

Fig. 1 is a schematic diagram of a conventional circuit breaker trip device.

Fig. 2 is a schematic view of an embodiment of the present invention.

Fig. 3 is a schematic view of another embodiment of the present invention.

Fig. 4 is a schematic view of another embodiment of the present invention.

In the figure: 1. conductor, 11, upper horizontal section, 12, lower horizontal section, 13, vertical section; 2. a bimetal; 3. the electromagnetic clutch comprises an electromagnet, 31, a fixing part, 311, a yoke, 3111, a yoke bottom plate, 3112, a yoke side plate, 312, a support, 3121, a support bottom plate, 3122, a support side plate and 32, an armature; 4. a gap; 5. riveting; 6. a heat insulating paperboard.

Detailed Description

The following detailed description of the embodiments of the present invention is provided in conjunction with the accompanying drawings, but the description of the embodiments is not intended to limit the technical solutions, and any changes made in the form of the present invention rather than the essential changes should be considered as the protection scope of the present invention.

In the following description, any concept related to the directionality (or the directional property) of up, down, left, right, front, and rear is intended for the position state of the drawing being described, and is intended to facilitate understanding by the public, and thus should not be construed as a limitation to the technical solution provided by the present invention.

Referring to fig. 2, the present invention relates to a circuit breaker tripping device, which comprises a conductor 1, a bimetallic strip 2 and an electromagnet 3, wherein when a circuit fails, an overload or short-circuit current flows through the conductor 1, the circuit breaker tripping device acts; the bimetallic strip 2 is in a strip shape, the lower end of the bimetallic strip is fixedly connected with the conductor 1, and the upper end of the bimetallic strip is a free end used for actuating the circuit breaker to trip when the circuit breaker is overloaded. When fault current flows through the conductor 1, the conductor 1 generates heat and transfers the heat to the bimetallic strip 2, the bimetallic strip 2 is heated and deformed, and the free end of the bimetallic strip is deformed to trigger the traction rod, so that the circuit breaker operating mechanism is pushed to be unlocked.

The structure of the electromagnet 3 also adopts the known technology, and when a short-circuit large current occurs in a circuit, the electromagnet 3 acts to push the circuit breaker operating mechanism to unlock. The electromagnet 3 includes a fixed portion 31 for fixed mounting and an armature 32 as a movable portion. The fixing portion 31 has a U-shaped cross section and includes a yoke 311 and a bracket 312. The yoke 311 includes a yoke base plate 3111 and a pair of yoke side plates 3112 formed by bending both sides of the yoke base plate 3111, and referring to fig. 2, the yoke base plate 3111 is bent toward the left side at both front and rear sides in a direction perpendicular to the paper surface to form a yoke side plate 3112, the support 312 includes a support base plate 3121 fixed to the yoke base plate 3111 in a superposed manner and a support side plate 3122 extended from the support base plate 3121, wherein the support side plate 3122 may be a pair formed by bending both front and rear sides in the direction perpendicular to the paper surface of the support base plate 3121 toward the left side, or a pair formed by extending both front and rear sides in the direction perpendicular to the paper surface of the support base plate 3121 upward to support the armature 31132 to rotate thereon, the armature 32 is pivoted on the support side plate 3122 and is correspondingly engaged with the pair of yoke side plates 2 to form a combined electromagnet, and in particular, when the armature 32 and the yoke 311 are engaged, the armature 32 and the end of the armature 3112 is brought into contact with the end of the armature 31132, and when the armature 3112 is released, the armature 32 is separated from the yoke side plate 3112. The conductor 1 includes an upper extension 11, a lower extension 12 and a vertical section 13, the upper extension 11 is used for connecting with a terminal, the lower extension 12 is used for electrically connecting with a movable contact of a circuit breaker, the vertical section 13 passes through a U-shaped cavity of the fixing portion 31, and in the embodiment shown in fig. 2, the vertical section 13 is disposed between a pair of yoke side plates 3112 and a yoke bottom plate 3111, that is, the side periphery of the vertical section 13 is enveloped by a yoke 311 and an armature 32. The lower end of the bimetal 2 is fixed to the side of the vertical section 13 facing away from the yoke base plate 3111. When a short-circuit fault occurs in the circuit, short-circuit current flows through the conductor 1, electromagnetic attraction is generated between the yoke 311 and the armature 32, the armature 32 rotates due to the electromagnetic attraction, the armature 32 is attracted with the pair of yoke side plates 3112 after the magnetic gap stroke is completed, and the action of the armature 32 triggers the traction rod to unlock the circuit breaker operating mechanism.

Example 1:

with continued reference to fig. 2, the support bottom plate 3121 or the yoke bottom plate 3111 is fixed to the conductor 1, but may also extend downward on the support bottom plate 3121 or the yoke bottom plate 3111 to form an extension to fix the conductor 1. In order to prevent the heat on the conductor 1 from being absorbed by the fixing portion 31, in the present embodiment, the fixing portion 31 is spaced from the conductor 1: a gap 4 is formed between the vertical section 13 and the fixing portion 31, where the gap 4 mainly refers to a gap between the vertical section 13 and the bracket bottom plate 3121 or the yoke bottom plate 3111 fixed thereto. In the prior art, gaps are formed between the vertical section 13 and the two yoke iron side plates 3112, and the gaps are not in contact with each other. In the prior art, the yoke 311 or the bracket 312 made of metal material is directly fixed in contact with the conductor 1, and the heat on the conductor 1 is transferred to the yoke 311 or the bracket 312, which corresponds to installing a heat sink on the conductor 1, thus affecting the action of the bimetal 2. The gap 4 can prevent or reduce the heat absorption of the yoke 311 or the bracket 312 on the conductor 1, and ensure the heating of the conductor 1 on the bimetallic strip 2, so that the bimetallic strip 2 can rapidly rise in temperature, and the reliability of the action of the tripping device is ensured.

Example 2:

referring to fig. 3 and fig. 2, a heat insulation paper board 6 is disposed in the gap 4. If the yoke bottom plate 3111 is fixed to the conductor 1, the heat insulating paper sheet 6 is located between the vertical section 13 of the conductor 1 and the yoke bottom plate 3111. The yoke bottom plate 3111, the heat insulation paper plate 6, the vertical section 13 of the conductor 1 and the bimetallic strip 2 are riveted and fixed in sequence through the rivet 5. If the support bottom plate 3121 is fixed with the conductor 1, the heat insulation paper board 6 is located between the vertical section 13 of the conductor 1 and the support bottom plate 3121, the heat insulation paper board 6, the vertical section 13 of the conductor 1 and the bimetallic strip 2 are riveted and fixed in sequence by the rivet 5. The arrangement of the heat insulation paper board 6 can further prevent or reduce the heat absorption of the yoke 311 or the bracket 312 on the conductor 1, and ensure the heating of the conductor 1 on the bimetallic strip 2, so that the bimetallic strip 2 can rapidly rise in temperature.

Example 3:

referring to fig. 4, in the embodiment, the fixing portion 31 is not directly fixed to the conductor 1, but is fixed to the circuit breaker base separately from the conductor 1, so that not only the conductor 1 and the fixing portion 31 are relatively fixed, but also a gap is ensured between the conductor 1 and the fixing portion 31, and heat on the conductor 1 is prevented from being conducted to the fixing portion 31.

Claims (7)

1. A circuit breaker tripping device comprises a conductor (1), a bimetallic strip (2) and an electromagnet (3), wherein the lower end of the bimetallic strip (2) is fixedly connected with the conductor (1), the upper end of the bimetallic strip is formed into a free end for actuating the circuit breaker to trip when a circuit is overloaded, the electromagnet (3) comprises a fixed part (31) which is fixedly installed and an armature (32) which is a movable part, and the circuit breaker tripping device is characterized in that: a gap (4) is formed between the fixing portion (31) and the conductor (1).

2. A circuit breaker trip unit according to claim 1, wherein the fixed portion (31) is U-shaped in cross-section, the armature (32) is pivotally mounted to the fixed portion (31), and the conductor (1) passes through the U-shaped cavity of the fixed portion (31) and is spaced from the fixed portion (31) to define the gap (4).

3. A circuit breaker trip unit as claimed in claim 2, wherein the gap (4) is provided with a thermally insulating paperboard (6).

4. The circuit breaker trip device according to claim 3, wherein the fixing portion (31) comprises a yoke (311) and a bracket (312), the yoke (311) comprises a yoke base plate (3111) and a pair of yoke side plates (3112) formed by bending two sides of the yoke base plate (3111), the bracket (312) comprises a bracket base plate (3121) fixed to the yoke base plate (3111) in an overlapping manner and a bracket side plate (3122) extending from the bracket base plate (3121), and the armature (32) is pivoted to the bracket side plate (3122) and is correspondingly matched with the pair of yoke side plates (3112).

5. A circuit breaker trip unit according to claim 4 wherein said thermal insulating paper sheet (6) is located between said conductor (1) and said yoke base plate (3111), thermal insulating paper sheet (6), conductor (1) and bimetal (2) are riveted in sequence by rivets (5).

6. The circuit breaker tripping device according to claim 4, wherein the heat insulation paper board (6) is located between the conductor (1) and the support bottom plate (3121), the heat insulation paper board (6), the conductor (1) and the bimetal strip (2) are riveted and fixed in sequence by the rivet (5).

7. A circuit breaker trip unit according to claim 1 wherein the conductor (1) and the mounting portion (31) are separately mounted to a circuit breaker base.

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