CN216793590U

CN216793590U - Thermomagnetic tripping mechanism and circuit breaker

Info

Publication number: CN216793590U
Application number: CN202220240553.4U
Authority: CN
Inventors: 李文擎; 刘云; 高杰
Original assignee: Legrand Low Voltage Wuxi Co Ltd
Current assignee: Legrand Low Voltage Wuxi Co Ltd
Priority date: 2022-01-28
Filing date: 2022-01-28
Publication date: 2022-06-21
Anticipated expiration: 2032-01-28

Abstract

The utility model relates to a thermomagnetic trip mechanism and a circuit breaker. The utility model comprises a thermal element for generating heat after being electrified; the bimetallic strip comprises a fixed part and a touch part connected with the fixed part, is connected with the thermal element and is used for receiving heat of the thermal element to generate bending deformation; the connecting terminal is connected with the thermal element and the bimetallic strip; the magnetic yoke assembly is connected to the wiring terminal and comprises a first magnetic yoke and a second magnetic yoke connected with the first magnetic yoke; and the magnetic tripping assembly is arranged on one side of the magnetic yoke assembly and is used for driving the draw bar of the circuit breaker to rotate. When overcurrent occurs, the thermal element and the bimetallic strip are heated simultaneously to heat the bimetallic strip, so that the thermal element does not need to select a high-resistance material, and the cost and the production energy consumption are saved; when a large current is generated, the breaking capacity and the return performance are improved because the instantaneous action time of the armature is far faster than the bending speed of the bimetallic strip.

Description

Thermomagnetic tripping mechanism and circuit breaker

Technical Field

The utility model relates to the technical field of low-voltage power distribution systems, in particular to a thermomagnetic tripping mechanism and a circuit breaker.

Background

The existing low-current circuit breaker usually adopts a coil excitation mode, so that an electromagnetic system of a low-current product has enough electromagnetic attraction, an armature is attracted, a product traction rod is pushed, and the product is tripped to protect a main loop.

However, the low-current circuit breaker with the current structure does not have enough electromagnetic attraction to enable a product to be tripped when a high-current fault occurs, a high-resistance thermal element is needed, and the production cost and the energy consumption are increased; in addition, not only the breaking capability is relatively low, but also the return performance of the bimetal is deteriorated after the bimetal is excessively heated, so that the small current circuit breaker cannot be used for the main circuit protection.

Disclosure of Invention

In order to solve the above technical problem, the present invention provides a thermomagnetic trip mechanism, comprising:

the thermal element is used for generating heat after being electrified;

the bimetallic strip comprises a fixed part and a touch part connected with the fixed part, is connected with the thermal element and is used for receiving heat of the thermal element to generate bending deformation;

the connecting terminal is connected with the thermal element and the bimetallic strip;

the magnetic yoke assembly is connected to the wiring terminal and comprises a first magnetic yoke and a second magnetic yoke connected with the first magnetic yoke;

and the magnetic tripping assembly is arranged on one side of the magnetic yoke assembly and is used for driving the draw bar of the circuit breaker to rotate through the magnetic yoke assembly.

In one embodiment of the present invention, the fixing portion is located at a bottom of the bimetal, and the drawbar is located above the touching portion.

In an embodiment of the utility model, the touching portion is an adjusting screw connected to the fixing portion.

In an embodiment of the present invention, the first magnetic yoke includes a first body and two first magnetic arms extending along both ends of the first body in the transverse direction, the second magnetic yoke includes a second body and two second magnetic arms extending along both ends of the second body in the transverse direction, a surface of the first body is attached to a surface of the second body, and an inner side surface of the first magnetic arm is attached to an outer side surface of the second magnetic arm.

In one embodiment of the present invention, a surface of the bimetal, a surface of the thermal element, and a surface of the second body are sequentially bonded to each other.

In one embodiment of the utility model, the bimetal and the thermal element are both located between the two second magnetic arms.

In one embodiment of the utility model, the bimetal and the thermal element are connected to the connection terminal by a fixing member.

In one embodiment of the utility model, the yoke assembly is located between the terminal and the thermal element.

In one embodiment of the utility model, the magnetic trip assembly comprises an armature and a bracket, the bracket is sleeved on two first magnetic arms of the first magnetic yoke, the bracket comprises an ear seat, the armature comprises a rotary lug and a rotary arm, the rotary arm is arranged on one side of a draw bar of the circuit breaker, the armature is rotatably connected into the ear seat through the rotary lug, and the rotary arm is rotated when the armature rotates.

The utility model also provides a circuit breaker comprising the thermomagnetic tripping mechanism, and the circuit breaker further comprises a moving contact component and a soft coupling, wherein the moving contact component is connected with the thermal element through the soft coupling.

Compared with the prior art, the technical scheme of the utility model has the following advantages:

according to the thermomagnetic tripping mechanism and the circuit breaker, when overcurrent occurs, the bimetallic strip is heated due to the simultaneous heating of the thermal element and the bimetallic strip, so that the thermal element does not need to select a high-resistance material, and the cost and the production energy consumption are saved; when a large current is generated, the breaking capacity and the return performance are improved because the instantaneous action time of the armature is far faster than the bending speed of the bimetallic strip.

Drawings

In order that the present disclosure may be more readily understood, a more particular description of the disclosure will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings

Fig. 1 is a schematic view of the overall structure of the thermomagnetic trip mechanism of the utility model.

Fig. 2 is a schematic structural view of the thermomagnetic trip mechanism of the present invention with the magnetic trip assembly omitted.

Fig. 3 is a schematic structural view of the thermo-magnetic trip mechanism of the present invention engaged with a drawbar.

The specification reference numbers indicate: 1. a thermal element; 2. a bimetal; 21. a fixed part; 22. a touch portion; 3. a wiring terminal; 31. a fixing member; 4. a first yoke; 41. a first body; 42. a first magnetic arm; 5. a second yoke; 51. a second body; 52. a second magnetic arm; 6. a magnetic trip assembly; 61. an armature; 611. ear turning; 612. a rotating arm; 62. a support; 621. an ear mount; 7. a draw bar; 8. a moving contact assembly; 81. a spring; 82. a shaft pin; 9. and (4) soft coupling.

Detailed Description

The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.

Referring to fig. 1 to 3, a thermomagnetic trip mechanism of the present invention includes:

a heat element 1 for generating heat after being energized;

the bimetal 2 comprises a fixed part 21 and a touch part 22 connected with the fixed part 21, and the bimetal 2 is connected with the thermal element 1 and used for receiving heat of the thermal element 1 to generate bending deformation;

the connecting terminal 3 is connected with the thermal element 1 and the bimetallic strip 2;

the magnetic yoke assembly is connected to the wiring terminal 3 and comprises a first magnetic yoke 4 and a second magnetic yoke 5 connected with the first magnetic yoke 4;

and the magnetic trip assembly 6 is arranged on one side of the magnetic yoke assembly and is used for driving the circuit breaker draw bar 7 to rotate through the magnetic yoke assembly.

Through the arrangement, when overcurrent exists, the thermal element 1 and the bimetallic strip 2 are heated simultaneously to heat the bimetallic strip 2, so that the thermal element 1 does not need to select a high-resistance material, and the cost and the production energy consumption are saved; when a large current is generated, the snap action time of the armature 61 is far faster than the bending speed of the bimetallic strip 2, so that the breaking capacity and the return performance are improved.

Specifically, the fixing portion 21 is located at the bottom of the bimetal 2, and the drawbar 7 is located above the touching portion 22; the touching portion 22 is an adjusting screw connected to the fixing portion 21, and the length of the adjusting screw can be adjusted to adjust the tripping time.

In particular, the yoke assembly is located between the terminal 3 and the thermal element 1; the first yoke 4 comprises a first body 41 and two first magnetic arms 42 extending along two transverse ends of the first body 41, the second yoke 5 comprises a second body 51 and two second magnetic arms 52 extending along two transverse ends of the second body 51, the surface of the first body 41 is attached to the surface of the second body 51, the inner side surface of the first magnetic arm 42 is attached to the outer side surface of the second magnetic arm 52, and the surface of the bimetal 2, the surface of the thermal element 1 and the surface of the second body 51 are sequentially attached; the bimetallic strip 2 and the thermal element 1 are both positioned between the two second magnetic arms 52, and the bimetallic strip 2 and the thermal element 1 are connected to the connecting terminal 3 through the fixing piece 31. In this embodiment, the fixing member 31 is a rivet but is not limited thereto.

Specifically, the magnetic trip assembly 6 includes an armature 61 and a bracket 62, the bracket 62 is sleeved on two first magnetic arms 42 of the first magnetic yoke 4, the bracket 62 includes an ear seat 621, the armature 61 includes a rotating ear 611 and a rotating arm 612, the rotating arm 612 is disposed on one side of the circuit breaker draw bar 7, the armature 61 is rotatably connected in the ear seat 621 through the rotating ear 611, and the rotating arm 612 is rotated when the armature 61 rotates.

Specifically, the moving contact assembly 8 and the soft coupling 9 are further included, the moving contact assembly 8 is connected with the thermal element 1 through the soft coupling 9 and is fixed on a circuit breaker base through the wiring terminal 3, and a moving contact system in the moving contact assembly 8 is assembled in a rotating shaft through a spring 81 and a shaft pin 82.

The working principle of the utility model is as follows: when normal current passes through the moving contact assembly 8, the current flows to the wiring terminal 3 from the thermal element 1 and the bimetallic strip 2 through the soft joint 9;

when overcurrent is generated and passes through the movable contact assembly 8, the current flows through the thermal element 1 and the bimetallic strip 2 through the flexible coupling 9, because the thermal element 1 and the bimetallic strip 2 simultaneously generate heat, the bimetallic strip 2 is heated and then deforms rapidly, and when the bending deformation reaches a certain degree, the delay adjusting screw touches the traction rod 7 so as to drive the mechanism to act and cut off the circuit;

when a large current passes through the moving contact system, the first magnetic yoke 4 and the second magnetic yoke 5 generate magnetic fields simultaneously, the magnetic fields generated by the two magnetic yokes are superposed, so that the armature 61 is sucked to realize instantaneous tripping, and the traction rod 7 can be rapidly triggered before the bimetallic strip 2 is heated and deformed so as to drive the mechanism to act to cut off a circuit.

Finally, it should be noted that the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to examples, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.

Claims

1. A thermomagnetic trip mechanism, comprising:

a thermal element (1) for generating heat after being energized;

the bimetal strip (2) comprises a fixing part (21) and a touch part (22) connected with the fixing part (21), the bimetal strip (2) is connected with the thermal element (1) and used for receiving heat of the thermal element (1) to generate bending deformation, and the touch part (22) is arranged on one side of a draw bar (7) of the circuit breaker;

the connecting terminal (3) is connected with the thermal element (1) and the bimetallic strip (2);

the magnetic yoke assembly is connected to the wiring terminal (3), and comprises a first magnetic yoke (4) and a second magnetic yoke (5) connected with the first magnetic yoke (4);

and the magnetic trip assembly (6) is arranged on one side of the magnetic yoke assembly and is used for driving the circuit breaker draw bar (7) to rotate through the magnetic yoke assembly.

2. A thermo-magnetic trip mechanism according to claim 1, characterised in that the fixed part (21) is located at the bottom of the bimetal blade (2) and the pull rod (7) is located above the touching part (22).

3. A thermomagnetic trip mechanism according to claim 1, wherein the contact portion (22) is an adjusting screw connected to the fixed portion (21).

4. A thermo-magnetic trip mechanism according to claim 1, wherein the first yoke (4) comprises a first body (41), two first magnetic arms (42) extending along both lateral ends of the first body (41), the second yoke (5) comprises a second body (51), two second magnetic arms (52) extending along both lateral ends of the second body (51), the surface of the first body (41) is attached to the surface of the second body (51), and the inner side of the first magnetic arm (42) is attached to the outer side of the second magnetic arm (52).

5. A thermomagnetic trip mechanism according to claim 4, characterized in that the surface of the bimetallic strip (2), the surface of the thermal element (1) and the surface of the second body (51) are in succession conformed.

6. A thermomagnetic trip mechanism according to claim 4, wherein the bimetallic strip (2) and the thermal element (1) are each located between two second magnetic arms (52).

7. A thermo-magnetic trip mechanism according to claim 1, characterised in that the bimetal (2) and the thermal element (1) are connected to the terminal (3) by a fixing member (31).

8. A thermomagnetic trip mechanism according to claim 1, characterized in that said yoke assembly is located between said terminal (3) and said thermal element (1).

9. A thermo-magnetic trip mechanism according to any of claims 1-8, characterized in that the magnetic trip unit (6) comprises an armature (61) and a bracket (62), the bracket (62) is sleeved on the two first magnetic arms (42) of the first magnetic yoke (4), the bracket (62) comprises an ear seat (621), the armature (61) comprises a rotary lug (611) and a rotary arm (612), the rotary arm (612) is arranged on one side of the circuit breaker draw bar (7), the armature (61) is rotatably connected in the ear seat (621) through the rotary lug (611), and the rotary arm (612) is rotated when the armature (61) rotates.

10. A circuit breaker comprising a thermomagnetic trip mechanism according to any one of claims 1 to 9, further comprising a moving contact assembly (8), a flexible coupling (9), said moving contact assembly (8) being connected to the thermal element (1) by means of the flexible coupling (9).