CN204651275U - A kind of miniature circuit breaker - Google Patents

Abstract

The utility model discloses a small circuit breaker, which comprises a housing, and a contact system, a thermal tripping system and an electromagnetic tripping system arranged in the housing; the contact system includes a moving contact and a static contact The thermal tripping system includes a thermal element and a bimetallic sheet; the thermal element is electrically connected to the wiring assembly adjacent to it, and the bottom end of the thermal element is welded and fixed to the bottom end of the bimetallic sheet; the thermal element and The bimetal sheet is respectively connected to the moving contact through a soft connection, and the moving contact has two welding parts respectively welded with the two soft connections, and the welding parts are formed with protrusions. In the small circuit breaker of the utility model, the current is shunted through the bimetal sheet and the heating element, which can effectively reduce the temperature rise. Interfering with the bending of the bimetal sheet, the delay characteristic of the thermal tripping system of the circuit breaker is more stable, and the electrical connection between the moving contact and the soft connection is reliable.

Description

A small circuit breaker

technical field

The utility model relates to a small circuit breaker.

Background technique

The main function of the miniature circuit breaker is overload long time delay and breaking instant. The overload long time delay is mainly realized through the thermal trip system. The direct current-carrying heating of the double gold works, which is called the direct heating type; the other is to work through the current-carrying heat of the thermal element being transferred to the double gold to cause heating and bending, which is called the side heating type. The thermal tripping system of the existing miniature circuit breaker is mainly a direct heating structure, and the current directly passes through the bimetal strip. When the current is large, the delay characteristic is generally unstable. The main reason is that the temperature rises and the soft The connection is thicker, which prevents the normal bending of the interfering bimetal.

Utility model content

In this regard, the purpose of this utility model is to provide a small circuit breaker with stable thermal tripping system delay characteristics and reliable electrical connection between the soft connection and the moving contact.

The technical scheme that realizes the utility model purpose is:

A small circuit breaker, including a housing, and a contact system, a thermal tripping system, and an electromagnetic tripping system arranged in the housing; the contact system includes a moving contact and a static contact; the thermal tripping The buckle system includes a thermal element and a bimetallic sheet; the thermal element is electrically connected to the wiring assembly adjacent to it, and the bottom end of the thermal element is welded and fixed to the bottom end of the bimetallic sheet; the thermal element and the bimetallic sheet The metal sheets are respectively connected to the movable contacts through one strand of soft connection, and the movable contact has two welding parts respectively welded with the two strands of soft connection, and the welding parts are stamped with protrusions.

In the above technical solution, the side part of the heating element is formed with terminal pins connected with the soft connection and the terminal assembly.

In the above technical solution, the electromagnetic tripping system is arranged above the arc extinguishing chamber, which includes a tripping coil and a magnetic guide plate, the tripping coil is welded to the static contact; the magnetic guide plate is formed with The contact angle that is in contact with the static contact.

In the above technical solution, a support boss is formed inside the housing, and the contact angle is clamped between the support boss and the static contact.

In the above technical solution, the position of the static contact that is welded to the tripping coil is provided with a plurality of protruding teeth that are convenient for welding.

In the above technical solution, the shape of the static contact and the magnetic conductive plate is favorable for introducing the arc into the arc striking angle of the arc extinguishing chamber.

The utility model has positive effects:

(1) In the miniature circuit breaker of the present utility model, the current is shunted through the bimetal sheet and the heating element, which can effectively reduce the temperature rise. At the same time, the original thick flexible connection is changed to two thin flexible connections, which can effectively avoid The soft connection hinders the bending of the interfering bimetal sheet, and the delay characteristic of the small thermal tripping system is more stable, especially when carrying a large current; Welding part, the welding part is stamped with protrusions, so that the protrusions are easier to melt when the soft connection is spot-welded with the moving contact, less prone to false welding, and the electrical connection is more reliable.

(2) In the utility model, the side of the heating element is formed with a connecting pin connected to the flexible connection and the wiring assembly, so as to open the distance between the flexible connection and the bimetal strip, and further prevent the flexible connection from The bending of the bimetal prevents interference.

(3) In the utility model, the tripping coil is welded to the static contact, and the magnetic conductive plate is in contact with the static contact through the contact angle on it, so that Two spot welding (the tripping coil is welded with the magnetic conducting plate, and the magnetic conducting plate is welded with the static contact) is changed to one spot welding (only the tripping coil and the static contact are welded), thereby reducing the high temperature during spot welding The impact on the tripping coil avoids the problem that the local conductive cross-section of the tripping coil becomes smaller due to the influence of high temperature, resulting in an increase in local temperature rise.

(4) In the utility model, the contact angle is clamped between the support boss and the static contact, which can effectively prevent the contact angle from being separated from the static contact, thereby ensuring that the magnetic guide plate and the static contact can always stay on.

(5) In the present utility model, the protruding teeth provided on the static contact can make the connection between the static contact and the tripping coil more convenient and reliable, because the teeth are more likely to melt during spot welding.

(6) In the present utility model, both the static contact and the magnetic guide plate are provided with an arc strike angle, which is conducive to guiding the faster arc generated between the east contact and the static contact. Enter the arc extinguishing chamber, thereby improving the arc extinguishing performance of the product.

Description of drawings

Fig. 1 is the internal view of the miniature circuit breaker of the present utility model;

Fig. 2 is a structural schematic diagram of the moving contact in the utility model;

Fig. 3 is a partial enlarged view of place A in Fig. 1;

Fig. 4 is a schematic structural diagram of the thermal tripping system in the present invention;

Fig. 5 is a schematic structural view of the thermal element in the present utility model;

Fig. 6 is a structural schematic diagram of the static contact in the utility model;

Fig. 7 is a schematic structural diagram of the magnetic guide plate in the present invention.

The reference signs shown in the figure are: 1-housing; 11-supporting boss; 2-moving contact; 21-welding part; 3-static contact; 4-heating element; Metal sheet; 6-interrupter; 61-trip coil; 62-magnetic plate; 63-contact angle; 7-arc angle; 8-wiring assembly.

Detailed ways

The specific structure of the miniature circuit breaker of the present utility model is described below in conjunction with the accompanying drawings of the description:

A small circuit breaker, as shown in Figures 1 to 4, includes a housing 1, and a contact system, a thermal tripping system, and an electromagnetic tripping system arranged in the housing 1; the contact system It includes a moving contact 2 and a static contact 3; the thermal tripping system includes a thermal element 4 and a bimetal 5; the thermal element 4 is electrically connected to a wiring assembly 8 adjacent to it, and the bottom end of the thermal element 4 The bottom end of the bimetal 5 is welded and fixed; the heating element 4 and the bimetal 5 are respectively connected to the moving contact 2 through a soft connection, and the moving contact 2 has two Welding parts 21 that are respectively welded to the two strands of soft connection, and the welding parts 21 are stamped with protrusions. In the miniature circuit breaker of this embodiment, the current is divided by the bimetal strip 5 and the heating element 4, which can effectively reduce the temperature rise. At the same time, the original thick flexible connection is changed to two thin flexible connections, which can effectively avoid the The connection hinders the bending of the interfering bimetal strip 5, and the delay characteristic of the thermal tripping system of the circuit breaker is more stable, and the effect is particularly obvious when carrying a large current; For the welding part, the welding part 21 is stamped with protrusions, so that the protrusions are easier to melt when the soft connection and the moving contact are spot-welded, less prone to false welding, and the electrical connection is more reliable.

In this embodiment, the side of the heating element 4 is formed with a terminal pin 41 connected to the flexible connection and the wiring assembly 8. This structure is used to widen the distance between the flexible connection and the bimetal 5, further avoiding The flexible connection hinders and interferes with the bending of the bimetal 5 , see FIG. 4 and FIG. 5 for details.

Further, the electromagnetic tripping system is arranged above the arc extinguishing chamber 6, which includes a tripping coil 61 and a magnetically conductive plate 62, the tripping coil 61 is welded to the static contact 3; the magnetically conductive plate 62 Formed on the top is a contact angle 63 that is in contact with the static contact 3, referring to Figure 7 for details. In this embodiment, the tripping coil 61 is welded to the static contact 3, and the magnetic conductive plate 62 is in contact with the static contact 3 through the contact angle 63 on it, so that the two spot weldings in the prior art (the tripping coil is welded with the magnetic conductive plate, and the magnetic conductive plate is welded with the static contact) are changed. One-time spot welding (only need to weld the tripping coil and the static contact), thereby reducing the impact of high temperature on the tripping coil 61 during spot welding, and avoiding the local conductive cross section of the tripping coil 61 being affected by high temperature becomes smaller and causes local The problem of rising temperature.

Further, referring to Fig. 3, a support boss 11 is formed inside the housing 1, and the contact angle 63 is clamped between the support boss 11 and the static contact 3, and this structure can Effectively prevent the contact angle 63 from being separated from the static contact 3, so as to ensure that the magnetic conductive plate 62 and the static contact 3 can always maintain a conduction state.

In this embodiment, the position of the static contact 3 welded with the tripping coil 61 is provided with a plurality of protruding teeth for welding; by setting the protruding teeth on the static contact 61, the static contact The connection between the head 3 and the tripping coil 61 is more convenient and reliable, because the teeth are more likely to melt during spot welding.

In order to improve the arc extinguishing performance of the product, in this embodiment, an arc starting angle 7 that facilitates introducing the arc into the arc extinguishing chamber 6 is provided on the static contact 3 and the magnetic conductive plate 62, as shown in Fig. 6 and Fig. 7.

In addition, the casing 1 in this embodiment is also formed with a positioning post, and the terminal pin 41 is formed with a positioning hole 42 matching with the positioning post, and the use of this positioning structure can facilitate thermal tripping The system is quickly installed in place, improving product assembly efficiency.

Apparently, the above-mentioned embodiments of the present utility model are only examples for clearly illustrating the present utility model, rather than limiting the implementation manner of the present utility model. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. And these obvious changes or changes derived from the essential spirit of the present utility model still belong to the protection scope of the present utility model.

Claims (6)

1. A small circuit breaker, comprising a housing (1), and a contact system, a thermal trip system and an electromagnetic trip system arranged in the housing (1); the contact system includes a moving contact (2) and static contact (3); the thermal tripping system includes a thermal element (4) and a bimetallic strip (5); the thermal element (4) is electrically connected to the wiring assembly (8) adjacent to it, The bottom end of the heat element (4) is welded and fixed to the bottom end of the bimetal sheet (5); it is characterized in that: the heat element (4) and the bimetal sheet (5) are respectively passed through a soft The connection is connected with the moving contact (2), and the moving contact (2) has two welding parts (21) respectively welded to the two soft connections, and the welding parts (21) are stamped with protrusions. 2. The miniature circuit breaker according to claim 1, characterized in that: the side part of the heating element (4) is formed with a terminal pin (41) connected with the soft connection and the wiring assembly (8). 3. The miniature circuit breaker according to claim 2, characterized in that: the electromagnetic tripping system is arranged above the arc extinguishing chamber (6), which includes a tripping coil (61) and a magnetically conductive plate (62), The tripping coil (61) is welded to the static contact (3); the magnetic conductive plate (62) is formed with a contact angle (63) that is in contact with the static contact (3). 4. The miniature circuit breaker according to claim 3, characterized in that: a support boss (11) is formed inside the housing (1), and the contact angle (63) is clamped on the support boss (11) and the static contact (3). 5. The miniature circuit breaker according to claim 4, characterized in that: the position of the static contact (3) welded to the tripping coil (61) is provided with a plurality of protruding teeth for welding. 6. The miniature circuit breaker according to claim 3, characterized in that: said static contact (3) and said magnetically conductive plate (62) are formed to facilitate the introduction of arc into said arc extinguishing chamber (6) Pilot angle (7).