WO2017124814A1

WO2017124814A1 - Time-delay operation mechanism used in circuit breaker, and circuit breaker

Info

Publication number: WO2017124814A1
Application number: PCT/CN2016/104531
Authority: WO
Inventors: 南寅; 王洪刚; 柴国卿
Original assignee: 首瑞（天津）电气设备有限公司
Priority date: 2016-01-21
Filing date: 2016-11-04
Publication date: 2017-07-27
Also published as: CN105513916A; CN105513916B

Abstract

A time-delay operation mechanism (100) used in a circuit breaker, and a circuit breaker. The time-delay operation mechanism (100) comprises: a static iron core (102); at least two movable iron cores (103,104) located on the same horizontal axis as the static iron core (102); at least two counterforce springs (105, 106) respectively located between the static iron core (102) and the movable iron core (103) adjacent thereto and between the at least two movable iron cores (103, 104); an electromagnetic coil (101) wound around the outside of at least one of the static iron core (102) and the at least two movable iron cores (103,104); and an ejector rod (107) penetrating the static iron core (102) and the at least two movable iron cores (103,104). When the electromagnetic coil (101) is energized, a magnetic motive force generated by a loop current in the electromagnetic coil (101) drives the at least two movable iron cores (103,104) to move towards the direction of the static iron core (102) by overcoming a resistance force generated by spring forces of the at least two counterforce springs (105, 106) so as to drive the ejector rod (107) to move, wherein at least one counterforce spring of the at least two counterforce springs (105, 106) generates a spring force different from that of the other counterforce spring. The time-delay operation mechanism (100) can realize the selective protection of stage difference coordination, thereby avoiding a simultaneous operation with a next-stage circuit breaker when a short-circuit current occurs.

Description

Delay action mechanism used in circuit breakers, and circuit breakers

Technical field

The present invention relates to the field of circuits, and more particularly to a time delay action mechanism for use in a circuit breaker, and a circuit breaker.

Background technique

The circuit breaker is mainly used to protect the wire or equipment in the terminal power distribution system. That is, when a fault current occurs in the terminal power distribution system, the circuit breaker cuts the fault current in time to prevent the accident causing the fault current from spreading. Currently, users generally set up multi-level circuit breaker protection. The general miniature circuit breaker has only two protection characteristics: overload long delay and short circuit instantaneous protection. When the fault short circuit current on the load side exceeds the trip value of the lower circuit breaker and exceeds the trip value of the upper circuit breaker, if the upper level If the circuit breaker has no short-circuit and short-delay protection function, the upper circuit breaker and the lower-level circuit breaker will trip at the same time, or the over-level trip (ie, the upper-level circuit breaker has tripped in the case that the lower-level circuit breaker has not tripped), so that the non-fault circuit Power failure, resulting in an expansion of the scope of the failure, resulting in unnecessary, greater economic losses. If the upper circuit breaker has the short-circuit short-delay protection function, the occurrence of simultaneous tripping or over-level tripping of the upper-level circuit breaker and the lower-level circuit breaker can be avoided, thereby preventing the expansion of the accident and improving the reliability and safety of the power supply.

Nowadays, users generally use the miniature circuit breaker (SMCB) with selective protection as the upper circuit breaker to achieve selective protection. However, both electronic and mechanical SMCB have the disadvantages of large size and high cost.

Summary of the invention

In view of one or more of the problems described above, the present invention provides a novel time delay action mechanism for use in a circuit breaker, and a circuit breaker.

The time delay action mechanism used in the circuit breaker according to the embodiment of the invention comprises: a static iron core; at least two moving iron cores on the same horizontal axis as the static iron core; at least two reaction force springs, respectively Located between the static iron core and the moving iron core adjacent thereto, and between the at least two moving iron cores; the electromagnetic coil is surrounded by the outside of the static iron core and at least one of the at least two moving iron cores; a rod extending through the static iron core and at least two moving iron cores, wherein when the electromagnetic coil is energized, the magnetic force generated by the loop current in the electromagnetic coil drives the at least two moving iron cores to overcome the spring force of the at least two reaction springs The generated resistance moves in a direction toward the static iron core to drive the ram movement, wherein at least one of the at least two reaction springs is different from the spring force generated by the other reaction springs.

The time delay action mechanism for use in a circuit breaker according to an embodiment of the present invention further includes: a sleeve, wherein at least two moving iron cores, and at least two reaction force springs are located inside the sleeve, and the electromagnetic coil surrounds the outer portion of the sleeve Wherein the sleeve is made of a material having insulating ability.

In the time delay action mechanism for use in a circuit breaker according to an embodiment of the present invention, at least two movable iron cores include a first moving iron core and a second moving iron core, and the first moving iron core is located at the static iron core and the second The spring force between the moving iron cores and the first reaction force spring between the first movable iron core and the static iron core is smaller than the spring force of the second reaction force spring between the first moving iron core and the second moving iron core .

In the time delay action mechanism used in the circuit breaker according to the embodiment of the present invention, when the first moving iron core is driven by the magnetic force generated by the loop current in the electromagnetic coil, it moves to the extreme position in the direction toward the static iron core. When the ejector pin does not reach the target position.

In the time delay action mechanism used in the circuit breaker according to the embodiment of the present invention, when the first moving iron core is driven by the magnetic force generated by the loop current in the electromagnetic coil, it moves to the extreme position in the direction toward the static iron core. At the time, the second moving core continues to move under the inertia and/or the magnetic force generated by the loop current in the electromagnetic coil until the jack reaches the target position.

In the time delay action mechanism used in the circuit breaker according to the embodiment of the present invention, the resistance generated by the spring force of the second reaction force spring increases during the movement of the second movable iron core in the direction toward the static iron core The large rate is greater than the rate of increase of the magnetic power generated by the loop current in the electromagnetic coil.

In the time delay action mechanism used in the circuit breaker according to an embodiment of the present invention, when the loop current in the electromagnetic coil exceeds the set action current threshold, the jack reaches the target position.

In the time delay action mechanism used in the circuit breaker according to the embodiment of the present invention, the first movable iron core has grooves or holes on the first movable iron core that do not hinder the continued movement of the second movable iron core.

A circuit breaker according to an embodiment of the invention includes a time delay action mechanism as described above.

The time delay action mechanism used in the circuit breaker according to the embodiment of the invention has a simple structure, low cost, and can realize selective protection of the step difference by the delay action of the trip mechanism, thereby avoiding short circuit current and lower level circuit breaking. The device acts at the same time.

DRAWINGS

The following drawings of the present application are hereby incorporated by reference in its entirety in its entirety herein in its entirety herein in its entirety The embodiments shown in the drawings and their description are to explain the principles of the invention. In the drawing:

1 is a partial cross-sectional view of a time delay action mechanism for use in a circuit breaker in accordance with an embodiment of the present invention;

2 is a partial enlarged view of a time delay action mechanism for use in a circuit breaker in accordance with an embodiment of the present invention.

detailed description

Features and exemplary embodiments of various aspects of the invention are described in detail below. In the following detailed description, numerous specific details are set forth However, it will be apparent to those skilled in the art that the present invention may be practiced without some of the details. The following description of the embodiments is merely provided to provide a better understanding of the invention. The present invention is in no way limited to any of the specifics of the details of the present invention, and it is intended to cover any modifications, substitutions and improvements of the elements and components without departing from the spirit of the invention. In the drawings and the following description, well-known structures and techniques are not shown in order to avoid unnecessary obscuring the invention.

In order to avoid the situation that the upper and lower circuit breakers trip at the same time or step over the trip to prevent the accident from expanding, the circuit breaker should have a short-circuit delay trip function to achieve selective protection of the step-difference. To this end, the present invention proposes a novel time delay action mechanism for use in a circuit breaker. A time delay action mechanism for use in a circuit breaker in accordance with an embodiment of the present invention will now be described in detail with reference to FIGS. 1 and 2.

Figure 1 illustrates a time delay action mechanism for use in a circuit breaker in accordance with an embodiment of the present invention. As shown in FIG. 1, the time delay action mechanism 100 used in the circuit breaker includes an electromagnetic coil 101, a static iron core 102, two moving

iron cores

103 and 104, two

reaction force springs

105 and 106, and a static iron. Core 102 and a jack 107 provided by the two

movable cores

103, 104.

In this embodiment, the electromagnetic coil 101 may be in the form of a solenoid structure, which surrounds the static iron core 102 and the outside of at least one of the two moving

iron cores

103, 104; the two moving

iron cores

103, 104 and The static iron core 102 is on the same horizontal axis, and the movable iron core 103 is located between the static iron core 102 and the moving iron core 104; the reaction force spring 105 is located between the static iron core 102 and the moving iron core 103, and the reaction force spring 106 Located between the moving

iron cores

103 and 104; the spring force generated by the reaction force spring 105 maintains the magnetic gap between the moving iron core 103 and the static iron core 102, and the spring force generated by the reaction force spring 106 causes the moving iron core 103 and The magnetic gap between 104 is maintained, and the spring force generated by the reaction spring 105 is less than the spring force generated by the reaction spring 106.

When the electromagnetic coil 101 is energized, the magnetic force generated by the loop current in the electromagnetic coil 101 drives the two moving

iron cores

103 and 104 against the resistance generated by the spring forces of the two

reaction springs

105 and 106 in the direction toward the static iron core 102. Movement, thereby driving the ejector 107 to move.

Here, since the spring forces of the

reaction springs

105 and 106 are different, 1) when the loop current in the electromagnetic coil 101 gradually increases from zero but has not increased until the driving force generated therefrom is greater than any of the reaction springs 105 and 106 When the resistance of one of the spring forces is generated, the two moving

iron cores

103 and 104 are unable to move; 2) when the loop current in the electromagnetic coil 101 is increased until the driving force generated by the spring coil 101 is greater than the spring force generated by the reaction force spring 105 When the resistance is smaller than the resistance generated by the spring force of the reaction force spring 106, the movable iron core 103 moves under the driving force generated by the loop current in the electromagnetic coil 101, and the movable iron core 104 moves under the movement of the movable iron core 103. Further, the jack 107 is moved by the moving

iron cores

103 and 104.

It will be understood by those skilled in the art that the time delay action mechanism used in the circuit breaker according to the embodiment of the present invention may include two or more movable iron cores and two or more reaction force springs disposed in cooperation with the movable iron core, and At least one of the two or more reaction springs has a different spring force than the other reaction springs. Thus, since the driving force generated by the loop current in the electromagnetic coil 101 has a temporal relationship with respect to the driving of the two or more moving iron cores, the jack 107 can be delayed to reach the target position.

In the embodiment shown in FIG. 2, when the moving iron core 103 is driven by the magnetic force generated by the loop current in the electromagnetic coil 101, it moves to the extreme position in the direction toward the static iron core 102 (for example, the reaction force spring 105 cannot The extreme position that is further compressed, or the moving iron core 103 is a static iron core When the 102 is held up so as to be unable to continue the extreme position in the direction of moving toward the static iron core 102, the jack 107 does not reach the target position; when the moving iron core 103 is driven by the magnetic force generated by the loop current in the electromagnetic coil 101 When moving toward the extreme position toward the static iron core 102, the movable iron core 104 continues to move under the action of inertia, magnetic force generated by the loop current in the electromagnetic coil 101, or both, until the push rod 107 reaches the target. The position (for example, the position at which the mouthpiece mechanism 109 is operated). During the movement of the movable iron core 104 in the direction toward the static iron core 102, the rate of increase of the resistance generated by the spring force of the reaction force spring 106 is greater than the rate of increase of the magnetic force generated by the loop current in the electromagnetic coil 101, such that The acceleration of the movable iron core 104 is made negative, so that the moving speed of the movable iron core 104 can be delayed.

In the circuit breaker including the time delay action mechanism 100, there is not only a magnetic gap between the moving iron core 103 and the static iron core 102 already existing in the existing circuit breaker, but also the existing circuit breaker does not exist yet. The magnetic gap between the iron core 103 and the moving iron core 104 increases the moving distance of the jack 107 compared to the existing circuit breaker, delaying the action of the tripping mechanism 109, so that the fault current in the circuit breaker is passed. It is cut off after the delay. In the present embodiment, when the loop current in the electromagnetic coil 101 exceeds the set operating current threshold, the jack 107 reaches the target position (i.e., reaches a position where the trip mechanism 109 is actuated such that the fault current in the circuit breaker is cut). .

In the embodiment shown in FIG. 2, the time delay action mechanism 100 used in the circuit breaker may further include a sleeve 108, wherein the sleeve 108 is made of a material having insulating ability. Specifically, the moving

iron cores

103 and 104, and the two

reaction force springs

105 and 106 are located inside the sleeve 108, and the electromagnetic coil 101 is wound around the outer surface of the sleeve 108. Here, the sleeve 108 not only serves to insulate between the moving

iron cores

103 and 104 and the electromagnetic coil 101, but also prevents the moving iron core 103 and the moving iron core 104 from swinging excessively in the radial direction, thereby improving the use thereof. The reliability of the time delay action mechanism 100 in the circuit breaker.

In order to better understand and apply the time delay action mechanism used in the circuit breaker according to the embodiment of the present invention, the time delay action mechanism 100 used in the circuit breaker shown in FIG. 1 is further described in detail below with reference to FIG. .

2 shows a partial enlarged view of a time delay action mechanism 100 for use in a circuit breaker in accordance with an embodiment of the present invention. As shown in FIG. 2, the outer diameter of the reaction force spring 105 is slightly smaller than the inner diameter of the sleeve 108, and the inner diameter is smaller than the boss 111 of the static iron core 102 and the boss 112 of the movable iron core 103. The diameter is slightly larger, and is located between the static iron core 102 and the movable iron core 103, and both ends are sleeved on the boss 111 of the static iron core 102 and the boss 112 of the movable iron core 103; the movable iron core 103 is provided with a cavity 113 and the bore 114; the jack 107 is in the shape of a stepped shaft, and the outer diameter of the thick shaft 115 of the jack 107 is larger than the inner diameter of the bore 114 of the movable core 103 and larger than the inner diameter of the bore 116 of the static iron core 102. The movable iron core 104 is provided with a cavity 117; the reaction force spring 106 is sleeved on the thin shaft 118 of the plunger 107, and the thin shaft 118 of the plunger 107 passes through the

holes

113 and 114 of the movable iron core 103 and extends into the hole The cavity 117 of the movable iron core 104 is provided with a limiting feature 119 on the base of the circuit breaker, so that the moving iron core 104 has a certain position, and the gap between the static iron core 102 and the moving iron core 103 is adjusted by adjusting the reaction force springs 105, 106. The gap between the movable iron core 103 and the moving iron core 104 has a predetermined predetermined value.

The magnetic force generated by the loop current in the electromagnetic coil 101 causes the movable iron core 103 to move toward the stationary iron core 102 against the resistance generated by the spring force of the reaction force spring 105 when the resistance generated by the spring force of the reaction force spring 105 is greater. The moving iron core 104 and the moving iron core 103 move together in the direction of the stationary iron core 102. When the movable iron core 103 reaches the limit position, the tripping mechanism does not operate, and there is enough between the movable iron core 103 and the moving iron core 104. Magnetic gap.

When the jack 107 is not driven to the trip position, the spring force of the reaction spring 106 gives the resistance of the movable core 104 a rate of increase that is slightly larger than the rate of increase of the magnetic force generated by the loop current in the solenoid 101. The acceleration of the movable iron core 104 is negative, delaying the moving speed of the moving iron core 104, and the moving iron core 104 overcomes the reaction force by the combination of the inertia and the magnetic force generated by the continuously increasing loop current in the electromagnetic coil 101. The resistance generated by the spring force of the spring 106 continues to move until the trip rod 107 is brought to the trip position to actuate the trip mechanism, thereby achieving the function of the mechanism delay trip.

In summary, it can be seen from FIG. 1 and FIG. 2 that the delay action mechanism used in the circuit breaker according to the embodiment of the present invention can realize the step difference matching selective protection function within a certain short circuit fault current range. Avoid power failure of non-faulty circuits, thus avoiding unnecessary economic losses and improving the reliability and safety of power supply.

The present invention has been described above with reference to the specific embodiments of the present invention, and it will be understood by those skilled in the art The spirit and scope of the invention are defined. In addition, any signal arrows in the figures should be considered as illustrative only and not limiting, unless otherwise Specific instructions. Combinations of components or steps will also be considered as already described when the term is foreseen to be unclear.

Claims

A time delay action mechanism for use in a circuit breaker, comprising:

Static iron core

At least two moving iron cores on the same horizontal axis as the static iron core;

At least two reaction force springs are respectively located between the static iron core and the movable iron core adjacent thereto, and between the at least two moving iron cores;

An electromagnetic coil surrounding the outside of the static iron core and the at least one of the at least two moving iron cores;

a jack through which the static iron core and the at least two moving iron cores are disposed, wherein

When the electromagnetic coil is energized, the magnetic force generated by the loop current in the electromagnetic coil drives the at least two moving iron cores against the spring force generated by the at least two reaction force springs toward the static iron The direction of movement of the core, thereby driving the jack, wherein at least one of the at least two reaction springs is different from the spring force generated by the other reaction springs.
The time delay action mechanism for use in a circuit breaker according to claim 1, further comprising:

a sleeve, wherein the at least two moving iron cores, and the at least two reaction force springs are located within the sleeve, and the electromagnetic coil surrounds the sleeve.
A time delay action mechanism for use in a circuit breaker according to claim 2, wherein said sleeve is made of a material having an insulating ability.
The time delay action mechanism for use in a circuit breaker according to any one of claims 1 to 3, wherein the at least two moving iron cores comprise a first moving iron core and a second moving iron core, a first moving iron core is located between the static iron core and the second moving iron core, and a spring force of the first reaction force spring between the first moving iron core and the static iron core is smaller than a spring force of a second reaction force spring between the first moving iron core and the second moving iron core.
A time delay action mechanism for use in a circuit breaker according to claim 4, wherein said first moving iron core is driven toward said magnetic force generated by a loop current in said electromagnetic coil When the direction of the static iron core moves to the extreme position, the ejector pin does not reach the target position.
A time delay action mechanism for use in a circuit breaker according to claim 5, wherein When the first moving iron core is moved to a limit position in a direction toward the static iron core driven by a magnetic force generated by a loop current in the electromagnetic coil, the second movable iron core is at inertia and/or Or the driving of the magnetic force generated by the loop current in the electromagnetic coil continues to move until the jack reaches the target position.
A time delay action mechanism for use in a circuit breaker according to claim 6, wherein said second reaction force is in a process of moving said second movable iron core in a direction toward said static iron core The rate of increase of the resistance generated by the spring force of the spring is greater than the rate of increase of the magnetic force generated by the loop current in the electromagnetic coil.
A time delay action mechanism for use in a circuit breaker according to claim 6 wherein said ram reaches said target position when a loop current in said solenoid exceeds a set operating current threshold.
A time delay action mechanism for use in a circuit breaker according to claim 4, wherein said first moving iron core has grooves or holes that do not interfere with the continued movement of said second moving iron core.
A circuit breaker comprising the time delay action mechanism of any of claims 1-9.