KR200212855Y1 - Electronic trip coil mechanism of circuit breaker - Google Patents

Abstract

The present invention relates to a circuit breaker for protecting a wire or an electric device connected to a load by detecting an abnormal current in the event of a short circuit accident or overload, and forming a runner and an assistant circuit in the radial direction of the magnet. Therefore, the trip operation can be done quickly and accurately even by applying low current, and the assembly structure can be minimized by simplifying the structure while reducing the number of parts.

The present invention is a yoke of a nonmagnetic material in the form of a container, a bobbin provided in the yoke, a magnet supported on one side of the bobbin, a strong magnetic body yoke plate connected to the magnet in a state in which the opening of the yoke is closed, and A moving core installed to be movable in the hollow part of the bobbin to protrude to the outside through the yoke through hole and sucked by the magnet, and the suction force of the magnet against the moving core when the driving current is applied to the bobbin is wound on the bobbin. A coil having a reducing function, an elastic member installed in the small diameter portion of the moving core to move the moving core to the trip position, and a shooter for releasing the latch of the opening / closing mechanism to trip when the moving core is moved to the trip position. Trip coil mechanism of wiring breaker.

Description

Electronic trip coil mechanism of circuit breaker

The present invention is installed on the transmission / distribution system or electric circuit to protect the wires or electrical equipment connected to the load by detecting the abnormal current and cutting off the current in case of an accident such as grounding or short circuit. It relates to a circuit breaker for wiring, and more particularly, to improve the structure of the trip coil mechanism installed for the trip operation of the circuit breaker to ensure the stability of the operation and to reduce the operating time.

In general, wiring breakers have overload protection, instantaneous tripping and short-circuit blocking, and basic elements such as contacts, trip devices, switchgear and extinguishing devices are installed inside the insulated container. have.

In addition, the circuit breaker is classified into a thermal type using a bimetal and an electronic device using an electronic device. The electronic wiring charger detects an overcurrent, an instantaneous current, or a short circuit current through a current converter, and detects a corresponding operation signal. As the coil is sent to the trip coil through the electronic circuit, the trip coil operates a mechanism of the circuit breaker to cut off the current.

1 and 2 are an exploded perspective view and assembled state cross-sectional view of an electronic trip coil mechanism applied to a conventional circuit breaker. The conventional electronic trip coil mechanism includes a yoke (1) and a yoke plate (2) constituting a housing, and the yoke and yoke A cylinder (3) fixed at the center between the plates, a bobbin (4), a shield plate (6), and a cap plate (7) installed between the yoke and the yoke plate in a state fitted to the outer surface of the cylinder; A coil 5 wound around the bobbin, a fixing core 8 fixed to one side of the cylinder, a moving core 9 movably installed in the cylinder, and a cylinder from one side of the yoke. A core pin 10 inserted through the central portion of the core and fixed to the moving core, a compression spring 11 installed between the core pin and the yoke to exert a force in one direction on the moving core, and the shield It consists installed on both sides of the rates (6) a magnet (12), and the like.

The electronic trip coil mechanism of the conventional circuit breaker as described above is a moving spring (9) by the holding force (suction force) of the magnet 12 in the normal operating state of the circuit breaker, that is, the energized state in which the breaker handle is inserted as shown in FIG. 11) overcoming the force and close to the fixing core (8) is in the charge (Charge) state, the short-circuit current or the overload current is applied to the coil (5) by detecting the current holding force of the magnet 12 is reduced As the core pin 10 moves to the left side in the drawing by the force of the compression spring 11 that is tensioned as shown in FIG. 2B, the moving core 9 fixed to the core pin 10 moves together, The opening and closing mechanism is connected to this to trip the breaker.

That is, while the breaker is operating normally, the moving core 9 moves toward the fixing core 8 while compressing the compression spring 11, and a disconnection current or an overload is detected and the bobbin 4 When a driving current is applied to the coil 5 wound around the coil 5, the magnetic flux in the opposite direction to the magnetic flux that holds (suctions) the moving core 9 as the coil 5 is excited is generated, and the magnetic flux to the runner on the coil 5 side. Instead of this decrease, the magnetic flux to the assistant on the magnet 12 side is increased and thus the amount of magnetic flux between the yoke 1 and the moving core 9 is reduced, so that the suction force of the magnet 12 is reduced. The moving core 9 is moved by a predetermined distance by the compression force of 11) to trip the breaker by interlocking the opening / closing mechanism.

In the wiring breaker as described above, the operation stability and the operation time of the mechanism are very important, and the operation stability depends on the strength of the magnetic flux, and the operation time depends on the time required for sensing current and outputting the operation signal and driving the switching mechanism. do.

In addition, the sensing time of the current and the output time of the operation signal are performed in the electronic circuits (P, C, B), and there is no significant difference in the required time. Therefore, the operation time of the circuit breaker mechanism is that the trip coil releases the latch of the switch. It depends on the time it takes until left and right, and this time varies greatly depending on the shape of the trip coil and its mechanism.

On the other hand, in order to increase the holding force for the operation stability of the mechanism in the trip coil mechanism, the strength of the magnetic flux generated in the opposite direction to the magnetic flux holding the moving core must be increased. For this purpose, the driving current applied to the coil must be increased in proportion to the magnitude of the holding force. However, the circuit board embedded in the circuit breaker has a limit in increasing the driving current applied to the coil because its load capacity is limited.

In addition, in order to increase the holding force, the number of windings of the coil must increase as the magnetic flux increases, thereby increasing the overall appearance of the trip coil mechanism, which is a limiting factor in miniaturizing the circuit breaker.

In particular, in the case of the trip coil of the conventional circuit breaker shown in FIGS. 1 and 2, a main passage and an auxiliary passage are formed in parallel with the axial direction of the moving core 9 so that the driving current must be increased to change the magnetic flux. As the magnet 12 becomes a rod, the distance between the moving core 9 and the magnet 12 varies depending on each point of the outer circumferential surface of the moving core 9 so that the magnet 12 There is a drawback that the suction force does not act uniformly on the moving core 9.

In addition, in the conventional trip coil mechanism, the magnetic flux generated in the magnet 12 is not used to create a holding force, but is distributed to the yoke 1 and the shield plate 6, so the holding force is small, and the trip coil mechanism is composed of many parts. Due to the severe change in characteristics, there is a problem that the characteristics must be adjusted by adjusting the voids to the assistant.

In addition, in order to speed up the operation time of the trip coil mechanism, the elastic force of the compression spring 11 should be increased. However, when the elastic force of the compression spring increases, the elastic force of the compression spring must have a large holding force that can overcome the elastic force. do.

An object of the present invention is to provide a trip coil mechanism of a circuit breaker that can reduce the operation time by bringing low current drive while increasing the holding force of the trip coil and bringing stability of operation and directly attaching the latch release mechanism to the trip coil itself. It is for.

According to an embodiment of the present invention for achieving the above object, a yoke of a nonmagnetic material in the form of a container, a bobbin installed in the yoke, a magnet supported on one side of the bobbin, and a state in which the opening of the yoke is closed A yoke plate of a strong magnetic material connected to the furnace magnet, a moving core installed in the hollow portion of the bobbin, and having a small diameter portion protruding outward through the yoke hole and being sucked by the magnet, are wound around the bobbin. A coil which serves to reduce the attraction force of the magnet to the moving core when the driving current is applied, an elastic member installed in the small diameter portion of the moving core to move the moving core to the trip position, and the moving core moves to the trip position The trip coil mechanism of the circuit breaker which consists of a shooter which unlocks and trips the latch of an opening / closing mechanism when provided is provided.

1 is an exploded perspective view showing a trip coil mechanism of a conventional circuit breaker

FIG. 2A is a longitudinal sectional view of FIG. 1 before a trip operation in which a moving core is attracted to a magnet;

2B is a longitudinal cross-sectional view of FIG. 1 after a trip operation in which a moving core is released;

3 is a plan view of an electronic trip coil mechanism according to the present invention;

4A is a longitudinal cross-sectional view of FIG. 3 before a trip operation in which a moving core is attracted;

FIG. 4B is a longitudinal cross-sectional view of FIG. 3 after the trip releasing moving core is released; FIG.

4C is a cross-sectional view taken along the line A-A of FIG. 4B

5a and 5b are magnetic flux distribution diagram of the electronic trip coil mechanism according to the present invention

6 is an assembled state diagram showing an example in which the electronic trip coil mechanism according to the present invention is applied to a circuit breaker;

Explanation of symbols for main parts of the drawings

21: York 22: bobbin

22a: hollow portion 23: coil

24: moving core 24a: small diameter part

25: magnet 26: yoke plate

27: elastic member 29: shooter

Figure 3 is a plan view of the electronic trip coil mechanism according to the present invention and Figure 4 is a longitudinal sectional view.

The bobbin 22 is provided in the yoke 21 of a nonmagnetic material in a container form, and the coil 23 is wound around the bobbin 22.

The hollow part 22a is formed in the bobbin 22, and the moving core 24 in the form of a double cylinder is movable in this hollow part 22a, and the small diameter part 24a of the moving core 24 is movable. ) Projects out of the yoke 21 through a hole 21a formed in the yoke 21.

One side of the bobbin 22 is provided with a ring-shaped magnet 25 for sucking and holding the moving core 24 and a yoke plate 26 of a ferromagnetic material.

The moving core 24 is compressed to the small diameter portion 24a of the moving core 24 protruding to the outside of the yoke 21 when the moving core 24 is attracted to the magnet 25 and then the moving core 24 when the moving core 24 is released. An elastic member 27 for imparting a restoring force to the 24 is provided by the E ring 28.

And in front of the moving core 24 to release the latch of the opening and closing mechanism while interlocking during the release of the moving core 24, when the breaker is inserted, the moving core 24 backward while interlocking with the handle and holding on the magnet 25 The shooter 29 which makes it become is provided.

The operation of the electronic trip coil mechanism of the present invention as described above will be described.

In the normal operating state in which the breaker is inserted, the moving core 24 is attracted to the magnet 25 by the suction force of the ring-shaped magnet 25 as shown in FIG. 4A, so that one side (the right side in the drawing) of the moving core 24 is the yoke plate ( 26, the elastic member 27 provided in the small diameter portion 24a of the moving core 24 is compressed.

At this time, in the present invention by installing the ring-shaped magnet 25 on one side of the bobbin 22 to allow the moving core 24 to move vertically to the inner diameter of the magnet 25, the yoke 21 to form a runner Instead of eliminating deformation as a runner, the yoke plate 26, which is a strong magnetic body on one side of the yoke 21, is positioned perpendicular to the magnet 25 so that a runner can be formed as shown in FIG. 5A. The magnetic flux generated by the magnet 25 affects the moving core 24 uniformly, and by using the magnetic flux sufficiently, the holding force of the moving core 24 can be increased.

That is, in the present invention, as the magnet 25 is used as the yoke 21 to be formed as the runner, the magnetic path between the moving core 24 and the magnet 25 becomes uneven, so that the yoke 21 is not a magnetic material. As a result, the magnetic path is made uniform and the yoke plate 26 is made of a strong magnetic material, so that sufficient magnetic flux can be generated to increase the holding force of the moving core 24.

In the state as shown in FIG. 4A, when a short circuit current or an overload is detected and a driving current is applied to the coil 23 wound on the bobbin 22 through a current converter, the coil 23 is excited to maintain the moving core 24. The magnetic flux in the opposite direction is generated, and as shown in FIG. 5B, the magnetic flux to the runner inside the magnet 25 is increased while the magnetic flux to the outside assistant is reduced, so that the magnetic flux amount between the yoke 21 and the moving core 24 is reduced. Since it is reduced, the suction force of the magnet 25 becomes small.

Therefore, the elastic member 27 installed in the small diameter portion 24a of the moving core 24 compresses the suction force of the magnet 25 and imparts a restoring force to the moving core 24, and the moving core 24 is It is released from the state held in the magnet 25 is moved in the left direction on the drawing to drive the shooter 29.

At this time, since the voids that make the holding force of the moving core 24 are the inner diameter of the ring-shaped magnet 25 on the yoke plate 26 and one side of the moving core 24 (right side in the drawing), a small driving current is applied to the coil 23. Even if the magnetic flux is easily moved to the outer diameter side of the magnet 25 and the yoke plate 26, the moving core 24 can be released with low current.

When the moving core 24 is released and the shooter 29 rotates as described above, as shown in FIG. 6, the shooter 29 hits the nail 30 of the opening / closing mechanism and releases the latch 31 to trip the opening / closing mechanism. In the present invention, since the shooter 29 can be rotated only by a small moving distance of the moving core 24, a tripping operation is quickly performed. When the breaker is reset, the shooter 29 is retracted by the handle 32 and the moving core is simultaneously retracted. 24 is retracted and held by the magnet 25.

Since the trip coil mechanism of the present invention uses a ring-shaped magnet 25, the suction force of the magnet acting over the entire circumferential surface along the radial direction of the moving core 24 is uniform and the holding force is increased. Unlike conventional mechanisms in which the furnace is formed along the axial direction of the moving core, the runners and the auxiliary furnaces are formed in the radial direction of the moving cores, so that the runners easily move to the assistants to suck the moving cores by applying low current. The volume will be reduced rapidly.

Therefore, the tripping trip of the breaker is quick and accurate.

In addition, the trip coil mechanism of the present invention reduces the number of parts and structurally simple compared to the conventional mechanism, thereby minimizing the tolerance due to assembly, and as the assembly tolerance is minimized, the change factor of the gyros becomes smaller, thereby improving reliability.

Claims (3)

Yoke 21 of a non-magnetic material in the form of a container having a through-hole 21a in the center and one side open, A bobbin 22 installed in the yoke and having a hollow portion 21a, A magnet 25 supported on one side of the bobbin 22, The strong magnetic body connected to the magnet in a state where the opening of the yoke is closed is the yoke plate 26, A moving core 24 which is installed to be movable in the hollow part of the bobbin so that the small diameter portion 24a on one side protrudes outwards through the yoke hole and is attracted to the magnet; A coil 23 wound around the bobbin and reducing the suction force of the magnet to the moving core when the driving current is applied; An elastic member 27 installed in the small diameter portion of the moving core and moving the moving core to the trip position when the suction force of the magnet against the moving core is reduced; Trip coil mechanism of a circuit breaker, comprising: a shooter 29 for releasing and latching the latch of the opening and closing mechanism when the moving core is moved to the trip position, and retracting the moving core to hold the magnet when the handle is inserted. The method of claim 1, Trip coil mechanism of the circuit breaker, characterized in that the magnet has a ring shape The method of claim 1, A groove portion is formed on one side of the bobbin and the trip coil mechanism of the circuit breaker, characterized in that the magnet is inserted into the groove portion to be supported without flow.