CN110957194B

CN110957194B - An improved moving contact system for low voltage circuit breaker

Info

Publication number: CN110957194B
Application number: CN201811133115.2A
Authority: CN
Inventors: 张鹏宇; 张广智; 李惠敏; 张海灵; 尹家灿
Original assignee: Shanghai Liangxin Electrical Co Ltd
Current assignee: Shanghai Liangxin Electrical Co Ltd
Priority date: 2018-09-27
Filing date: 2018-09-27
Publication date: 2024-10-22
Anticipated expiration: 2038-09-27
Also published as: CN110957194A

Abstract

An improved low-voltage circuit breaker moving contact system is characterized in that: at least one compensation bracket (11) is arranged among a plurality of parallel conductive plates (10) of the moving contact system, and the compensation bracket (11) can provide support for a rotary support shaft (12) of the moving contact system to reduce radial deformation of the rotary support shaft after receiving power. This low-voltage circuit breaker moving contact system through setting up compensation support and both ends curb plate cooperation, prevents that rotatory back shaft from radially deforming after receiving the electric power, plays compensation supporting role to increase the bending deformation resistance ability of back shaft, simultaneously can increase the current-carrying area of contact piece through reducing the diameter of rotatory supporting axle, reduced the temperature rise.

Description

Improved moving contact system of low-voltage circuit breaker

Technical Field

The invention belongs to the technical field of piezoelectric devices, and particularly relates to an improved low-voltage circuit breaker moving contact system.

Background

The circuit breaker is an important part of a power distribution electrical appliance, and is mainly used for an industrial low-voltage power system, and is used for switching on and off current in a power grid circuit, protecting a circuit and power supply equipment from damage caused by faults such as overload, undervoltage, short circuit, single-phase grounding and the like. The circuit breaker is classified into a high voltage circuit breaker and a low voltage circuit breaker according to its range of use. The low-voltage circuit breaker is also called an automatic switch, commonly called an air switch, and also refers to a low-voltage circuit breaker, and is an electric appliance which has the function of manual switching and can automatically perform voltage loss, undervoltage, overload and short-circuit protection. It can be used to distribute electric energy, not frequently start asynchronous motor, protect power supply circuit and motor, when they are in serious overload or short circuit and under-voltage, it can automatically cut off circuit, its function is equivalent to the combination of fuse switch and over-under-heating relay, etc. and after breaking fault current it generally does not need to change parts, so that it has been widely used.

The circuit breaker application occasions in the existing market require that some circuit breakers have short-time tolerance performance, and the contact resistance between the moving contact and the fixed contact of the circuit breaker plays a crucial role in the performance of the circuit breaker for bearing short-time tolerance current. The larger the contact resistance between the movable contact and the fixed contact of the circuit breaker is, the larger the heat productivity of the circuit breaker is when carrying short-circuit current, and then the contacts of the movable contact and the fixed contact (the movable contact on the movable contact and the fixed contact on the fixed contact) are welded and even damaged. As for the moving contact of the circuit breaker, as the short-time withstand current of the circuit breaker increases, the electric repulsive force applied to the moving contact of the circuit breaker also increases, and as shown in fig. 1, the moving contact structure of the circuit breaker in the prior art comprises a group of parallel conductive plates 1, a flexible conductive connecting wire 2, a conductive block 3, a group of contact springs 4, a contact support 5, a pair of support plates 6, a rotary support shaft 7, a contact cover 8 and a contact system bracket 9. The upper ends of a pair of support plates 6 are fixed with two sides of a contact support 5, the lower ends are connected with a conductive block 3, a contact cover 8 is covered outside a group of parallel conductive plates 1, the two ends are fixed with the pair of support plates 6, the nearly middle part of the group of parallel conductive plates 1 penetrates through the middle part of a rotary support shaft 7 positioned on the pair of support plates 6 at the two ends, and is connected with one end of a flexible conductive connecting wire 2, and the other end of the flexible conductive connecting wire 2 is fixed on the conductive block 3. According to the moving contact structure, as the short-time tolerance current value of the circuit breaker increases, the electric repulsive force born by the moving contact of the circuit breaker also increases, and the rotary support shaft is easy to bend and deform under the action of the electric repulsive force, so that poor contact between the moving contact and the stationary contact is caused, and the contact resistance is increased. Meanwhile, the structural strength of the rotary support shaft in the moving contact structure cannot be improved by increasing the diameter. And along with the increase of the phase spacing of the circuit breaker, the width of each phase of movable contact is also increased, the diameter of the rotary supporting shaft is unchanged, the length is increased, the strength is reduced, and the bending deformation defect of the circuit breaker is further increased.

Disclosure of Invention

The invention aims at solving the technical defects that the over travel of the circuit breaker is reduced and the contact system is repelled when the short-time endurance is short caused by the easy bending deformation of a rotary supporting shaft of the prior circuit breaker moving contact system, through setting up compensation support and both ends curb plate cooperation, increase the strong point of rotatory back shaft to increase the bending deformation resistance ability of back shaft, simultaneously through reducing the diameter of rotatory supporting axle, increase the current-carrying area of contact piece, reduced the temperature rise.

Technical proposal

In order to achieve the technical purpose, the invention relates to an improved moving contact system of a low-voltage circuit breaker, which is characterized in that: at least one compensation bracket is arranged among the plurality of parallel conductive plates of the moving contact system, and the compensation bracket can provide support for the rotary support shaft of the moving contact system to reduce radial deformation of the rotary support shaft after receiving power.

Further, the compensation bracket is provided with a limit notch tangential to the rotary supporting shaft, the inner side of the compensation bracket is provided with a limit lug, the limit lug is inserted into a limit groove corresponding to the limit lug on the contact support, and the bottom of the compensation bracket is also provided with a connecting block fixedly installed together with the contact support.

Further, one side of the compensation bracket facing the contact cover is provided with a plurality of pins, and the pins are inserted into corresponding pin receiving grooves on the contact cover.

Further, the moving contact system comprises parallel conductive plates with silver contacts, soft joints, connecting buses, contact springs, contact supports, supporting plates, rotating supporting shafts, contact covers and contact system supports, wherein a plurality of parallel conductive plates are arranged on the rotating supporting shafts side by side, the lower ends of the conductive plates are arranged together with the soft joints, the soft joints are arranged on the contact system supports, the connecting buses are arranged together with the contact system supports, the rotating supporting shafts are arranged on the supporting plates, the supporting plates are arranged together with the contact supports, one sides of the back of the conductive plates are provided with the contact covers, one ends of the contact springs are arranged on the conductive plates, and the other ends of the contact springs are arranged on the contact supports.

Advantageous effects

According to the improved moving contact system of the low-voltage circuit breaker, the compensation support is arranged to be matched with the side plates at the two ends, so that the radial deformation of the rotary support shaft after power is received is prevented, the compensation support function is achieved, the bending deformation resistance of the support shaft is improved, meanwhile, the current carrying area of the contact piece can be increased through reducing the diameter of the rotary support shaft, and the temperature rise is reduced.

Drawings

Fig. 1 is a schematic diagram of a conventional moving contact system.

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

Detailed Description

The invention will be further described with reference to the drawings and examples.

Examples

As shown in fig. 2, an improved moving contact system of a low-voltage circuit breaker comprises a parallel conductive plate 10 with silver contacts, a soft connection 15, a connection bus bar 16, a contact spring 17, a contact support 13, a support plate 18, a rotary support shaft 12, a contact cover 14 and a contact system support 15, wherein a plurality of parallel conductive plates 10 are arranged on the rotary support shaft 12 side by side, the lower end of the conductive plate 10 is arranged with the soft connection 15, the soft connection 15 is arranged on the contact system support 15, the connection bus bar 16 is arranged with the contact system support 15, the rotary support shaft 12 is arranged on the support plate 18, the support plate 18 is arranged with the contact support 13, one side of the back of the conductive plate 10 is provided with a contact cover 14, one end of the contact spring 17 is arranged on the conductive plate 10, and the other end is arranged on the contact support 13.

At least one compensation bracket 11 is arranged between the parallel conductive plates 10, and the compensation bracket 11 can provide support for a rotary support shaft 12 of the moving contact system to reduce radial deformation of the rotary support shaft after receiving power.

The compensating bracket 11 is provided with a limit notch 1101 tangential to the rotary supporting shaft 12, the inner side of the compensating bracket 11 is provided with a limit bump 1102, the limit bump 1102 is inserted into a corresponding limit groove 1301 on the contact supporting 13, and the bottom of the compensating bracket 11 is also provided with a connecting block 1103 which is fixedly arranged together with the contact supporting 13. The side of the compensation bracket 11 facing the contact cover 14 is provided with a plurality of pins 1104, and the pins 1104 are inserted into corresponding pin receiving grooves 1401 on the contact cover 14.

According to the improved moving contact system of the low-voltage circuit breaker, the compensation support is arranged to be matched with the side plates at the two ends, so that the radial deformation of the rotary support shaft after the power is received is prevented, the compensation support function is achieved, the bending deformation resistance of the support shaft is improved, meanwhile, the current carrying area of the contact blade can be increased by reducing the diameter of the rotary support shaft, and the temperature rise is reduced.

The structures, proportions, sizes, amounts, etc. shown in the drawings of the embodiments of the present invention are for illustration and description only, and should not be construed as limiting the invention, so that any structural modifications, proportional changes, or adjustments of size may fall within the scope of the invention without affecting the efficacy and achievement of the invention. Meanwhile, the terms such as "upper", "lower", "left", "right", "middle", "clockwise", "anticlockwise" and the like are used in the present specification for convenience of description, and are not intended to limit the scope of the present invention, and the relative relation changes or modifications thereof are considered to be within the scope of the present invention without substantial modification of the technical content.

Claims

1. An improved low-voltage circuit breaker moving contact system, characterized in that: at least one compensation bracket (11) is arranged between a plurality of parallel conductive plates (10) of the moving contact system, and the compensation bracket (11) can provide support for the rotating support shaft (12) of the moving contact system to reduce its radial deformation after receiving electric force;

The compensation bracket (11) is provided with a limiting notch (1101) which is tangent to the rotating support shaft (12); the inner side of the compensation bracket (11) is provided with a limiting protrusion (1102); the limiting protrusion (1102) is inserted into a corresponding limiting groove (1301) on the contact support (13); the bottom of the compensation bracket (11) is also provided with a connecting block (1103) which is fixedly mounted together with the contact support (13);

A plurality of plug pins (1104) are provided on a side of the compensation bracket (11) facing the contact cover (14), and the plurality of plug pins (1104) are inserted into corresponding plug pin connection slots (1401) on the contact cover (14).

2. An improved low-voltage circuit breaker moving contact system as claimed in claim 1, characterized in that: the moving contact system comprises parallel conductive plates (10) with silver contacts, a soft connection (15), a connecting busbar (16), a contact spring (17), a contact support (13), a support plate (18), a rotating support shaft (12), a contact cover (14) and a contact system bracket (15), a plurality of parallel conductive plates (10) are arranged side by side on the rotating support shaft (12), and the conductive plates (10 ) is mounted together with a soft connection (15), the soft connection (15) is mounted on a contact system bracket (15), the connecting busbar (16) is mounted together with the contact system bracket (15), the rotating support shaft (12) is mounted on a support plate (18), the support plate (18) is mounted together with the contact support (13), a contact cover (14) is mounted on one side of the back of the conductive plate (10), one end of the contact spring (17) is mounted on the conductive plate (10), and the other end is mounted on the contact support (13).