KR102388640B1 - A breaker - Google Patents

Abstract

Embodiments of the present disclosure provide a circuit breaker. The circuit breaker includes: a shaft including a first section and a second section; a movable contact assembly arranged on the shaft along an extension direction of the shaft and including a movable contact; and a drive mechanism coupled to the first section that drives the movable contact assembly to rotate with the shaft such that the movable contact contacts or disengages the static contact of the circuit breaker; The shaft further includes an insulating layer disposed on the first section and the second section. An effective insulating protection for the shaft is achieved by the insulating layer arranged on the first section and the second section, thereby avoiding breakdown of the shaft in case of a short circuit and reducing the risk of an interphase short circuit.

Description

Breaker {A BREAKER}

BACKGROUND Embodiments of the present disclosure relate generally to electrical devices, and more particularly to circuit breakers in which a shaft is insulated.

A circuit breaker can turn on, carry, and turn off current under normal circuit conditions, and can turn on, carry, and automatically turn off current under prescribed abnormal circuit conditions (eg, short circuit current). Refers to an electrical device capable of Circuit breakers are widely used in various electrical scenarios in production and daily life, and are an important guarantee for safe electricity use. The shaft made of metal in circuit breaker is prone to breakdown during short circuit under high voltage environment, causing phase to phase short circuit and extremely large hidden safety hazards.

summary

In conventional circuit breaker products, in particular double-breaking point circuit breakers, one or two shafts made of metal are commonly used to ensure the synchronization of the actions of the contacts and the modular assembly of the contacts. It passes through to form support for each phase. However, metal shafts are easily broken down upon short circuit to cause an inter-phase short circuit, which occurs particularly easily under AC/DC high voltage environment. A short circuit between phases will cause serious harm to the circuit breaker itself and to the circuit protected by the circuit breaker.

In order to solve or at least partially solve the above and other potential problems, embodiments of the present disclosure provide an effective insulation protection without changing the overall structure of the circuit breaker and reducing the risks of occurrence of inter-phase short circuit. , a circuit breaker using a shaft having an insulating layer.

In one aspect of the present disclosure, a circuit breaker is provided. The circuit breaker includes: a shaft including a first section and a second section; a movable contact assembly arranged on the shaft along an extension direction of the shaft and including a movable contact; and a driving mechanism coupled to the first section that drives the movable contact assembly to rotate with the shaft so that the movable contact contacts or disengages the static contact of the circuit breaker. wherein the shaft further comprises an insulating layer disposed on the first section and the second section.

According to the circuit breaker of the embodiments of the present disclosure, effective insulation protection for the shaft is achieved by the insulating layer disposed on the first section and the second section, thereby avoiding breakdown of the shaft in case of short circuit and interphase short circuit reduce the risk of Therefore, such a circuit breaker can be applied more widely and is more suitable for use under a high voltage environment.

In some embodiments, the first section and the second section are made of metal, and the diameter of the first section is greater than the diameter of the second section. In these embodiments, the shaft body is made of metal, which ensures easy workability and mechanical performance of the shaft itself. On the other hand, the shaft body is made in a stepped shape by setting the diameter of the second section to be smaller than the diameter of the first section. Accordingly, a thicker insulating layer may be arranged on the second section to further improve the insulating protection for the shaft.

In some embodiments, the insulating layer includes a first insulating coating disposed on the first section. In such embodiments, an insulating coating may be disposed on the first section to further enhance the insulating protection without reducing the mechanical performance of the shaft. Also, since the shaft is coupled to a drive mechanism (such as a linkage) in the first section, a wear-resistant insulating coating may be selected to improve the wear resistance of the shaft and reduce the loss of overrun.

In some embodiments, the insulating layer further comprises an insulating sleeve disposed on the second section. In such embodiments, the insulating sleeve may be mounted onto the second section of the shaft after the first section of the shaft is coupled to the drive mechanism. In this way, the difficulty of installation is reduced, while the insulating sleeve is prevented from being worn when passing through the drive mechanism.

In some embodiments, the insulating layer further comprises an insulating sleeve and a second insulating coating disposed on the second section. In such embodiments, the second insulating coating on the second section may be formed with the first insulating layer on the first section, and the insulating sleeve may be conveniently installed on the second section. In this way, the insulation protection for the shaft is further improved without increasing the difficulties in installation and manufacture.

In some embodiments, the thickness of the insulating sleeve is in the range of 0.1 mm to 0.3 mm. In such embodiments, effective insulation protection is achieved using a thinner insulation sleeve without reducing the robust mechanical performance of the shaft.

In some embodiments, the insulating layer disposed on the second section is formed by an injection molding process. In such embodiments, the insulating layer integral with the second section may be formed using an injection molding process, thereby resulting in uniform and reliable insulating protection.

In some embodiments, the shaft has the same diameter in the first section and in the second section. In such embodiments, synchronization and consistency of the operations of the movable contacts of the different poles of the circuit breaker may be ensured by configuring the shaft to have a uniform diameter in the different sections.

In some embodiments, the first section is located in a middle portion of the shaft and the second section includes adjacent portions at opposite ends of the shaft. In such embodiments, insulation protection may be achieved for circuit breakers having more than two poles.

In some embodiments, the circuit breaker is a four-pole circuit breaker. In such embodiments, a widely usable 4-pole circuit breaker with good shaft insulation may be formed.

In some embodiments, the circuit breaker is a three-pole circuit breaker. In such embodiments, a widely usable 3-pole circuit breaker with good shaft insulation may be formed.

Additional features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. It is to be understood that this Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Other features of the subject matter described herein will become apparent from the description that follows.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features, and advantages of exemplary embodiments of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings, in which the same reference signs denote exemplary embodiments of the present disclosure. points to the same elements in
1 shows an overall schematic diagram of a circuit breaker, in accordance with an exemplary embodiment of the present disclosure;
FIG. 2 shows a partial cross-sectional view of the circuit breaker shown in FIG. 1 .
3 shows a schematic diagram of an internal structure of the circuit breaker shown in FIG. 1 .
4 shows a schematic diagram of forming a circuit breaker shaft, in accordance with an exemplary embodiment of the present disclosure;
5 shows a schematic diagram of a circuit breaker shaft, in accordance with an exemplary embodiment of the present disclosure;
Throughout the drawings, the same or similar reference signs refer to the same or similar elements.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present disclosure will now be described with reference to several exemplary embodiments. It should be understood that these embodiments are merely described to enable those skilled in the art to better understand and thereby practice the present disclosure, and are not intended to suggest any limitation on the scope of the technical solutions of the present disclosure.

As used herein, the term “comprises” and variations thereof are to be read as open-ended terms meaning “including but not limited to”. The term “based on” should be read as “based on at least partly”. The terms “one example implementation” and “example implementation” should be read as “at least one example implementation”. The term "another implementation" should be read as "at least one other implementation". The terms “first,” “second,” and others may refer to different or the same objects. The text below may also contain other explicit or implicit definitions. Unless the context explicitly dictates otherwise, definitions of terms are consistent throughout the specification.

As mentioned above, a shaft made of metal in a circuit breaker is prone to breakdown upon short circuit, especially under high voltage (> AC 690 V) or DC (> DC 1000 V) environment, causing a short circuit between phases. In the case of a normal short circuit, current flows sequentially through the poles of the circuit breaker. However, when a dielectric breakdown occurs between the metal shaft and other components (eg, static contacts) in the circuit breaker, an interphase short circuit is caused. In the case of a phase-to-phase short circuit, the path of the current is greatly reduced, and even damage to the circuit breaker is caused. Thus, the phase-to-phase short circuit causes extreme harm.

In some traditional solutions, in order to reduce the risk of a phase-to-phase short circuit, the shaft of the circuit breaker is formed as an all-plastic shaft, or the shaft is formed by facing or sandwiching a plastic member and a metal segment. In these traditional solutions, although the insulation of the shaft is improved, the difficulty in manufacturing the shaft is increased and the mechanical performance is reduced.

SUMMARY Embodiments of the present disclosure provide a circuit breaker including a shaft having an insulating layer to solve, or at least partially solve, these and other potential problems. Some exemplary embodiments will now be described with reference to FIGS. 1-5 .

First, the overall structure of the circuit breaker 100 according to an exemplary embodiment of the present disclosure will be described in detail with reference to FIGS. 1 to 3 . 1 shows an overall schematic diagram of a circuit breaker 100 according to an exemplary embodiment of the present disclosure; FIG. 2 shows a partial cross-sectional view of the circuit breaker 100 shown in FIG. 1 ; 3 shows a schematic diagram of an internal structure 300 of the circuit breaker shown in FIG. 1 .

As shown in FIG. 1 , in general, the circuit breaker 100 described herein is a four-pole circuit breaker comprising poles 111-114, wherein each pole is connected to a phase line or a zero line. are adapted The circuit breaker 100 further includes a drive mechanism 105 . As shown in FIG. 2 , the drive mechanism 105 may include a handle, an operating mechanism, a linkage mechanism, and the like. The scope of the present disclosure is not limited to a specific drive mechanism, and thus it is not described in detail herein. The drive mechanism 105 is positioned at at least one pole of the circuit breaker, for example at the pole 112 . Pole 112 may also be referred to as instrument pole 112 .

Components such as shaft 310 , movable contacts 302 and stationary contacts 304 are located within housing 103 of circuit breaker 100 . As shown in FIG. 3 , the circuit breaker 100 includes two shafts 310 , the shaft 310 includes a first section 311 and a second section 312 , wherein the first One section 311 is located on the instrument pole 112 . Each of the poles 111-114 of the circuit breaker 100 includes a contact circuit consisting of a static contact 304 , a movable contact 302 , a contact support 303 , and the like. The movable contact assembly including the movable contact 302 and the contact support 303 is arranged on the shaft 310 along the extension direction of the shaft 310 .

The drive mechanism 105 is coupled to the first section 311 of the shaft 310 and drives the movable contact assembly to rotate with the shaft 310 so that the movable contact 302 is a static contact of the circuit breaker 100 . It is adapted to make contact with the 304 or to be removed from the static contact 304 . In the simplified schematic diagram of FIG. 3 , a linkage 305 constituting part of the drive mechanism 105 is shown. The linkage 305 is coupled to the first section 311 . When the linkage 305 is lowered or raised upward, the shaft 310 causes the movable contacts 310 of the individual poles to simultaneously contact or disengage from the corresponding static contact 304 . will close or open the corresponding contact circuit.

It should be understood that the illustration of circuit breaker 100 as a four-pole circuit breaker is illustrative only and is not intended to limit the scope of the present disclosure. Embodiments of the present disclosure may be applied to various circuit breakers, such as a two-pole circuit breaker, a three-pole circuit breaker, and the like. Further, the drive mechanism may be coupled to any pole of the circuit breaker. Although the circuit breaker 100 is shown as having two shafts in FIGS. 1-3 for illustrative purposes, it is understood that a circuit breaker according to embodiments of the present disclosure may have a larger or smaller number of shafts. should understand

In order to increase the insulating protection of the shaft and reduce the risk of an interphase short circuit, in addition to the body of the shaft, the shaft 310 further includes an insulating layer disposed on the first section 311 and the second section 312 . The insulating layer of shaft 310 may be formed in any suitable manner including, but not limited to, insulating coating, insulating sleeve, injection molding, and the like. The insulating layers on the first section 311 and the second section 312 may be formed in the same or different ways, and may have the same or different thicknesses.

A shaft 310 according to an embodiment of the present disclosure will be described in detail below with reference to FIGS. 4 to 5 . 4 shows a schematic diagram of forming a circuit breaker shaft 310 , in accordance with an exemplary embodiment of the present disclosure. 5 shows a schematic diagram of a circuit breaker shaft 310 , in accordance with an exemplary embodiment of the present disclosure.

In the example of FIG. 4 , the shaft 310 comprises a stepped shaft body, for example made of metal, which comprises a first section 311 and a second section 312 . The diameter d1 of the first section 311 is larger than the diameter d2 of the second section 312 . The shaft body made of metal is easy to machine and helps to ensure the shaft's strong mechanical performance. The length L1 of the first section 311 and the lengths L2 and L3 of the second section 312 may be set according to actual needs.

A first insulating coating 401 is disposed on the first section 311 . The first insulating coating 401 may be formed in any suitable manner, such as by coating, spraying, or the like. Since the drive mechanism 105 is coupled to the shaft 310 in the first section 311 , a component such as the linkage 305 will cause wear to the first insulating coating 401 . Thus, in some embodiments, the first insulating coating 401 may be formed as an abrasion resistant insulating coating, eg, the first insulating coating 401 may be formed as an oxide coating (such as alumina). In this way, not only the insulation protection of the shaft 310 is strengthened, but also the wear resistance of the shaft 310 is improved, thereby avoiding loss of overrun.

In some embodiments, the insulating layer disposed on the second section 312 may be formed using an insulating sleeve 402 , such as a thermoplastic sleeve. As shown in FIG. 3 , in this case, after the body of the shaft 310 (eg, an insulating layer is disposed on the first section) is installed in the circuit breaker 100 , the insulating sleeve 402 . may be directly sleeved onto the second section 312 . This reduces the difficulty of installation and prevents the thermoplastic sleeve from abrading as it passes through the instrument.

The thickness of the insulating sleeve 402 may be selected as needed. A good insulating effect can also be achieved with a thin thermoplastic sleeve. The thickness of the insulating sleeve 402 may be in the range of 0.1 mm to 0.3 mm. By way of example only, a thermoplastic sleeve having a thickness of 0.15 mm can effectively prevent the phase-to-phase short circuit of the shaft, and increase the creepage distance of the mating phase. After testing, no breakdown occurred between dielectric phases for 5 seconds under 3000 Vdc voltage condition.

In some embodiments, the insulating layer disposed on the second section 312 may include, for example, a second insulating coating formed with the first insulating coating 401 , the second insulating coating comprising the first insulating coating 401 . It may have the same thickness as the insulating coating 401 or a different thickness than the first insulating coating 401 . In some embodiments, the insulating sleeve 402 may further be disposed on the second insulating coating, which may further enhance the insulating protection of the shaft 310 .

In some embodiments, the insulating layer disposed on the first section 311 or the second section 312 may also be formed by an injection molding process. For example, a shaft body comprising a first section 311 and a second section 312 may be placed in a mold and then on the first section 311 and second section 312 . The insulating layer may be formed by injection molding. In some embodiments, when the first insulating coating 401 is disposed on the first section 311 , both ends of the shaft 310 each form an insulating layer on the second section 312 , It may also be placed in an injection molding mold.

5 schematically illustrates a formed shaft 310 comprising an insulating layer, which comprises a first section 311 and a first insulating coating 401 disposed on the first section 311, a second section ( 312 and an insulating sleeve 402 disposed over the second section 312 thereof. The shaft 310 has a diameter D1 in the first section 311 and a diameter D2 in the second section 312 . In some embodiments, diameter D1 may be substantially equal to diameter D2. A formed shaft with a uniform diameter facilitates synchronization of the operations of the movable contacts 302 of the different poles. However, this is not limiting, and it should be understood that a circuit breaker according to embodiments of the present disclosure may also have different diameters in the first section 311 and the second section 312 .

In the above-described examples, the first section 311 is located in the middle portion of the shaft 310 , and the second section 312 includes portions close to both ends of the shaft 310 . It should be understood that this is illustrative only and is not intended to limit the scope of the present disclosure. The positions of the first section and the second section may be set according to actual needs. For example, for a two-pole circuit breaker, the first section and the second section may include a left end portion and a right end portion of the shaft, respectively.

It should be understood that all numerical values set forth in the above detailed embodiments of the present disclosure are exemplary, and all numerical values are optional.

It is to be understood that the above detailed embodiments of the present disclosure are for the purpose of merely illustrating and explaining the principles of the present disclosure, rather than limiting the present disclosure. Accordingly, any modifications, equivalent substitutions and improvements made within the spirit and principles of this utility model should be included in the protection scope of this utility model. On the other hand, the claims appended to this disclosure are intended to cover all variations and modifications falling within the scope and boundaries of the claims and their equivalents.

Claims (11)

A circuit breaker (100) comprising:
two shafts 310 each including a first section 311 and a second section 312 ;
a movable contact assembly arranged on the two shafts (310) along the extension direction of the two shafts (310) and including a movable contact (302); and
a drive mechanism (105) coupled to the first section (311), which drives the movable contact assembly to rotate together with the two shafts (310) so that the movable contact (302) is the circuit breaker (100) the drive mechanism (105) in contact with or disengaged from the static contact (304) of
Each of the two shafts (310) further comprises an insulating layer disposed on the first section (311) and the second section (312). The method of claim 1,
the first section (311) and the second section (312) are made of metal, and the diameter (d1) of the first section (311) is larger than the diameter (d2) of the second section (312); Circuit Breaker (100). The method of claim 1,
The insulating layer comprises a first insulating coating (401) disposed on the first section (311). 4. The method of claim 3,
The insulating layer further comprises an insulating sleeve (402) disposed over the second section (312). 4. The method of claim 3,
wherein the insulating layer further comprises an insulating sleeve (402) disposed on the second section (312) and a second insulating coating. 6. The method according to claim 4 or 5,
The thickness of the insulating sleeve (402) is in the range of 0.1 mm to 0.3 mm. The method of claim 1,
and the insulating layer disposed on the second section (312) is formed by an injection molding process. The method of claim 1,
Each of the two shafts (310) has the same diameter in the first section (311) and the second section (312). The method of claim 1,
The first section 311 is located in the middle portion of each of the two shafts 310 , and the second section 312 includes portions adjacent to both ends of each of the two shafts 310 . which, circuit breaker 100. The method of claim 1,
The circuit breaker (100) is a 4-pole circuit breaker (100). The method of claim 1,
The circuit breaker (100) is a three-pole circuit breaker (100).

Images