JP2000082376A - Voltage tripping device for circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a voltage tripping device which is embodied in a small size and at a low cost and can be assembled easily. SOLUTION: An electromagnet is actuated with a signal voltage to cause a plunger 22 protruding to press a trip bar 16, and after tripping, the current feed to the electromagnet is stopped by a burnout preventive switch 24, and thus a voltage tripping device is constructed, wherein the middle part is borne so that rotatability is secured and there an operating lever 26 is provided, whereby an engage/disengage part 26b at one end is engaged with or disengaged from a movable contacting piece in accordance with the opening/closing motions of an opening/closing mechanism while an engaging finger part 26a at the other end is engaged with the plunger 22 and also a push grip 26c is engaged with an operation button 24a on the switch 24, and further a reset spring 28 is installed to cause the finger part 26a to energize and rotate the plunger 22 in the resetting direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage trip device which is built in a circuit breaker and which operates to shut off the circuit breaker by an external signal voltage.

[0002]

2. Description of the Related Art FIG.
FIG. 8 is a perspective view showing a conventional voltage trip device for a circuit breaker disclosed in Japanese Patent Application Publication No. H10-209, FIG. FIGS. 9A and 9B are partial side sectional views showing a state in which a switching device is tripped or turned off in a state where a conventional voltage trip device is incorporated in a circuit breaker. In the figure, reference numeral 1 denotes a voltage trip device, 2 denotes an electromagnet unit, and a coil 2a and a yoke 2
b, plunger guide 2c, anvil 2d (not shown)
It is composed of 3a and 3b are lead wires for applying a signal voltage from the outside, and 4 is a burnout prevention switch, which is connected in series with the coil 2a of the electromagnet unit 2. 5 is a plunger of the electromagnet part 2, 6 is a lever,
It is composed of an arm 6a and a leg 6b, is rotatably supported on the yoke 2b by a pin 7, and is normally urged by a reset spring 8 in a counterclockwise direction in the figure. Reference numeral 9 denotes a mounting base for holding the electromagnet unit 2 and the burnout prevention switch 4. Reference numeral 10 denotes an actuator, which is supported on the mounting base 9 by a shaft 9a and which is normally operated by an actuator spring 11 (not shown).
Is pressed, and the burnout prevention switch 4 is in a conductive state. Reference numeral 12 denotes an outer case of the voltage trip device 1, which is mounted in the direction of the arrow.

In FIG. 8, reference numeral 14 denotes a movable contact,
The movable contact 14a is fixed to the tip. A fixed contact 15 is a fixed contact 15a opposed to the movable contact 14a.
Is fixed. Reference numeral 16 denotes a trip bar, which is connected to an opening / closing mechanism (not shown) by the operation of the trip bar 16 and connects both contacts of the movable contact 14 and the fixed contact 15 via the cross bar 17 as shown in FIG. Open and cut off the electrical circuit.

Next, the operation of the conventional voltage trip device will be described. When a signal voltage is externally applied to the lead wires 3a and 3b in order to operate the voltage trip device, the coil 2a
The magnets 2 are excited by an electric current, and an electromagnetic force is generated in the electromagnet portion 2, and the plunger 5 is attracted to the anvil 2d (not shown).
The arm 6a of the lever 6 rotates in conjunction with the suction of the plunger 5, and the leg 6b rotates about the pin 7 to push the trip bar 16 to operate the opening / closing mechanism. The circuit breaker is tripped by the operation of the switching mechanism.

In FIG. 9, as the cross bar 17 is turned from the ON position to the OFF position by the trip operation, the cross bar 17 causes the actuator 10 to rotate the shaft 9a against the urging force of the actuator spring 11 (see FIG. 7). ) Is lifted up from the center to release from the operation button of the burnout prevention switch 4, so that the burnout prevention switch 4 is turned off, and the current of the coil 2a connected in series is cut off. Therefore, even if a voltage is continuously applied after the circuit breaker trips, the coil 2a is protected from burning. When the circuit breaker is in the off state, the crossbar 17 is in the same manner as in the trip state.
Pushes up the actuator 10, the burnout prevention switch 4 is off, and no current flows through the coil 2a, so that burnout is prevented.

In the reset state of the circuit breaker, the actuator 10 is released from the cross bar 17 and the operating button of the burnout prevention switch 4 is pressed by the urging force of the actuator spring 11. Therefore, the burnout prevention switch 4 is turned on, and the coil 2a can be energized. Then, the lever 6 is pushed back by the reset spring 8, and the plunger 5 returns to the initial position.

[0007]

The prior art circuit breaker voltage trip device includes an actuator 10 which is biased by an actuator spring 11 incorporated in the shaft 9a as described above.
And the two shaft portions of the lever 6 urged by the reset spring 8 incorporated in the pin 7, and assembling was complicated. In addition, since the shaft protrudes, the external shape of the voltage trip device becomes large, and there is a problem that a large space for incorporating the circuit breaker is required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a small and inexpensive voltage trip device which is easy to assemble.

[0009]

The voltage trip device for a circuit breaker according to the present invention is characterized in that an electromagnet is actuated by a signal voltage so that a protruding plunger presses a trip bar and, after tripping, burns out. In a device in which energization to the electromagnet is stopped by a prevention switch, an intermediate portion is pivotally supported so as to be rotatable, and an engagement / disengagement portion at one end engages / disengages with the movable contact according to the opening / closing operation of the opening / closing mechanism, and engages at the other end. One actuating lever configured so that the finger engages the plunger and the pusher engages the actuation button of the burnout prevention switch, and the engaging finger engages the plunger in the reset direction. And a reset spring for rotating the power.

The plunger is provided with a fixed spring stopper and a movable spring stopper which abuts the fixed spring stopper to hold the plunger spring and to return between the step formed on the plunger and the movable spring stopper. A spring is interposed, and the engaging finger portion of the operating lever is engaged with the plunger via a movable spring stopper and a return spring.

The push lever of the operating lever is formed of an elastic member capable of deforming by a predetermined amount, so that the burnout prevention switch is turned off, and then the operating lever is further rotated to the reset position by the elastic deformation of the push lever. It is made possible.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 1 to 3 are partial side sectional views of a circuit breaker voltage trip device according to a first embodiment of the present invention. 1 is a side sectional view showing the relationship between the voltage trip device and the crossbar 17 when the circuit breaker is on, FIG. 2 is a side sectional view illustrating the voltage trip operation, and FIG. FIG. 4 is a side sectional view showing a relationship between a voltage trip device and a crossbar 17 in a state. In the figure, 14 is a movable contact, 14a is a movable contact, 15 is a fixed contact, 15a is a fixed contact, 16 is a trip bar, and 17 is a crossbar. Axis for rotation. These are the same as those of the above-described conventional device.

Reference numeral 20 denotes a voltage trip device, and reference numeral 20a denotes a frame of the voltage trip device 20. 21 is an electromagnet part,
It is composed of a release coil 21a, a yoke 21b, and a permanent magnet 21c, and is assembled to the frame 20a. 22
Is a plunger made of a magnetic material, and a release coil 2
The push rod 22a is provided so as to be slidable at the core of 1a, and is in a positional relationship of pressing the trip bar 16. Reference numeral 23 denotes a plunger spring, which is provided between a spring stopper 22 b fixed to the plunger 22 and the electromagnet section 21, and acts so as to press the plunger 22 against the trip bar 16.

Reference numeral 24 denotes a burnout prevention switch, which is electrically connected in series with the release coil 21a by a lead wire 25. When the operation button 24a of the burnout prevention switch 24 is pressed, the circuit to the release coil 21a is cut off. It is wired as follows. Reference numeral 26 denotes an operation lever, and the frame 20a
Is rotatably supported by a support shaft 27 provided at the center. An engaging / disengaging portion 26 formed at one end of the operating lever 26
b engages with an engagement projection 17a provided upright on the cross bar 17. An engaging finger 26a formed at the other end of the operating lever 26 is provided with a spring stopper 22 fixed to the plunger 22.
b. Then, the pusher portion 2 facing the operation button 24a of the burnout prevention switch 24 is provided at an intermediate portion between the engagement finger portion 26a of the operation lever 26 and the support shaft 27.
6c is provided. A reset spring 28 urges the operating lever 26 in the clockwise direction in the drawing, and has an urging force stronger than the force of the plunger spring 23 on the side of the engagement finger 26a that engages with the plunger 22. .

In the above configuration, when the circuit breaker shown in FIG. 1 is turned on, the plunger 22 is attracted to the permanent magnet 21c by the force of the plunger spring 23, and the push rod 2
2a is located away from the trip bar 16. The engagement / disengagement portion 26b of the operation lever 26 is pressed by the engagement projection 17a of the cross bar 17 and is rotated counterclockwise. Thus, the engaging finger 26a of the operating lever 26 and the plunger 22 are in a disengaged positional relationship.
6c is also in a non-contact state with the operation button 24a of the burnout prevention switch 24. Therefore, the burnout prevention switch 24 is on, and the release coil 21a can be energized.

Next, when a signal voltage is applied from the lead wire 25 to the release coil 21a in the ON state of the circuit breaker, the current of the release coil 21a reduces the attraction force of the permanent magnet 21c. The force of the jar spring 23 becomes stronger than the attraction force, and the plunger 22 is pushed to the left in the drawing (the direction indicated by the arrow in FIG. 2). When the plunger 22 is pushed out, the trip bar 16 is pressed as shown in FIG. 2 to operate an opening / closing mechanism (not shown). By this operation, the cross bar 17 connected to the opening / closing mechanism is rotated, and both contacts of the movable contact 14 and the fixed contact 15 are separated. As described above, when the cross bar 17 is rotated so as to separate both contacts, the engagement / disengagement portion 26b of the operation lever 26 is released from the pressing of the engagement projection 17a, and is clockwise rotated by the urging force of the reset spring 28. To the state shown in FIG. The clockwise rotation of the operating lever 26 causes the pusher 26c to press the operating button 24a, so that the burnout prevention switch 24 is turned off. Therefore, even if the application of the signal voltage is continued, the release coil 21a is not energized, so that problems such as burning of the release coil 21a or a high temperature state are solved. Then, the engagement finger 26a of the operation lever 26 causes the plunger 22 to be attracted to the permanent magnet 21c against the urging force of the plunger spring 23, and is reset.

In the circuit breaker voltage trip device constructed as in the first embodiment, the operating lever 26 which rotates in response to the ON / OFF or trip state of the circuit breaker is provided.
Further, by providing the pusher portion 26c for switching the burnout prevention switch 24, the actuator and the actuator spring are not required as compared with the conventional device, so that the assembling is easy and a small voltage trip device can be obtained.

Embodiment 2 FIG. In the first embodiment, the attraction force of the permanent magnet 21c is reduced by applying a signal voltage to the release coil 21a in the ON state of the circuit breaker, and the plunger 22 is moved by the plunger spring 23 so that the trip bar 16 is moved. Press to activate the opening and closing mechanism. With this operation, the cross bar 17 rotates, and the engagement projection 17a releases the engagement of the engagement / disengagement portion 26b of the operation lever 26. When the engagement / disengagement portion 26b is released, the operating lever 26 rotates clockwise to push the button 24a of the burnout prevention switch 24 to cut off the power supply to the release coil 21a. Next, the engaging finger 26a of the operating lever 26 is configured to attract the plunger 22 to the permanent magnet 21c at the reset position.

By the way, the above-mentioned structure is, for example, due to the variation of the dimensions of the components of each part, for example, due to the plunger 22.
Before reaching the reset position in which the plunger 22 is attracted to the permanent magnet 21c, the pusher portion 26c pushes the operation button 24a to a stop and stops, so that the plunger 22 cannot move to the reset position and cannot be reset. is there. On the contrary, the plunger 22 reaches the reset position before the burnout prevention switch 24 is turned on, and the operating lever 26 cannot move any further.
For this reason, the burnout prevention switch 24 may not be switched, and it may not be possible to apply a signal voltage to the release coil 21a. The second embodiment is for solving the above-mentioned problem.

4 and 5 are partial side sectional views of a circuit breaker voltage trip device according to a second embodiment of the present invention. FIG. 4 is a side sectional view illustrating a voltage trip operation of the circuit breaker, and FIG. 5 is a side sectional view illustrating a relationship between the voltage trip device and the plunger when the circuit breaker is in a trip or off state. In the figure, 14 is a movable contact, 14a is a movable contact, 15 is a fixed contact, 15a is a fixed contact, 16 is a trip bar, and 17 is a crossbar. Reference numeral 20 denotes a voltage release device, reference numeral 20a denotes a frame of the voltage release device 20, and reference numeral 21 denotes an electromagnet portion, which is composed of a release coil 21a, a yoke 21b, and a permanent magnet 21c.
Has been assembled. 22 is a plunger, 22a is a push rod, 23 is a plunger spring, 24 is a burnout prevention switch, 24a is an operation button, 25 is a lead wire, 26 is an operation lever, 26a is an engaging finger, 26b is an engaging and disengaging portion, Reference numeral 27 denotes a support shaft, and reference numeral 28 denotes a reset spring, which are the same as those described in the first embodiment.

Reference numeral 30 denotes a fixed spring stop for transmitting the urging force of the plunger spring 23 to the plunger 22. Reference numeral 31 denotes a fixed spring stop that abuts on the fixed spring stop 30 and the push rod 22a. It is a movable spring stopper movably inserted. A return spring 32 is interposed between the movable spring stopper 31 and the step 22c of the plunger 22. The engaging finger 26a of the operation lever 26 is
The fork has a larger interval than the fixed spring stopper 30. Therefore, the engaging finger 26a is formed so as not to engage with the fixed spring stopper 30, but with the movable spring stopper 31.

Next, the operation of the voltage trip device according to the second embodiment will be described. In the transition from the state of the voltage tripping operation of FIG. 4 to the reset of FIG. 5, while the engagement finger 26a of the operation lever 26 moves rightward, the operation lever 2
6 engages the plunger spring 23 and the return spring 32 via the movable spring stopper 31. First,
The movement of the plunger 22 to the right via the return spring 32 starts. This movement compresses the plunger spring 23. Then, the plunger 22 is pressed against the reset position, that is, against the permanent magnet 21c. Plunger 2
2 comes into contact with the permanent magnet 21c,
Is absorbed by the compression of the return spring 32.
Therefore, while the plunger spring 23 and the return spring 32 are compressed, the pusher portion 26c is reliably connected to the burnout prevention switch 24.
Switch on.

As described above, the plunger 22 is pressed to the reset position, and the return spring 32 for absorbing the movement of the engagement finger 26a of the operating lever 26 is provided. Since the permissible dimensional range of the switching width can be increased, the plunger 22 pushes the burnout prevention switch 24 before the plunger 22 reaches the reset position, so that the plunger 22 cannot be reset, and the plunger 22 reaches the reset position first and burns out. This prevents the prevention switch 24 from being turned on.

Embodiment 3 FIG. Third Embodiment FIG. 6 is a partial side sectional view of a circuit breaker voltage trip device according to a third embodiment of the present invention. In the figure, 14 is a movable contact, 14a is a movable contact, 15 is a fixed contact, 15a is a fixed contact, 16 is a trip bar, and 17 is a crossbar. Reference numeral 20 denotes a voltage release device, reference numeral 20a denotes a frame of the voltage release device 20, and reference numeral 21 denotes an electromagnet portion, which is composed of a release coil 21a, a yoke 21b, and a permanent magnet 21c.
Has been assembled. 22 is a plunger, 22a is a push rod, 23 is a plunger spring, 24 is a burnout prevention switch, 24a is an operation button, 25 is a lead wire, 26 is an operation lever, 26a is an engaging finger, 26b is an engaging and disengaging portion, Reference numeral 27 denotes a support shaft, and reference numeral 28 denotes a reset spring, which are the same as those described in the first embodiment.

Reference numeral 26d denotes a pusher portion extending from the operating lever 26 and formed to be capable of elastic deformation by a predetermined amount. The elastically deformable pusher 26 d is provided to face the operation button 24 a of the burnout prevention switch 24. In this configuration, when the circuit breaker is on, the operating lever 26 is rotated counterclockwise by the engaging projection 17a of the cross bar 17, and in this state, the pusher 26d of the elastic member opens with the operating button 24a. When released, the burnout prevention switch 24 is on, and can be connected to the release coil 21a.

On the other hand, when the circuit breaker is turned off, the engagement between the engaging projection 17a and the engaging / disengaging portion 26b of the operating lever 26 is released, and the operating lever 26 is rotated clockwise by the biasing force of the reset spring 28. On the way to return to the reset position, the pusher 26d of the elastic member pushes the operation button 24a and then deforms due to its elasticity so as not to hinder the return of the operation lever 26 to the reset position. Can be completely pressed to the reset position to be sucked.

As described above, after the operating button 24a of the burnout prevention switch 24 is depressed, it is elastically deformed and does not prevent the operating lever 26 from returning to the reset position.
Since the setting is d, the button 24a of the burnout prevention switch 24 is surely pushed in before the plunger 22 reaches the reset position. Therefore, the reset failure of the plunger 22 can be eliminated.

Although FIG. 6 shows a case in which the pusher portion 26d of the elastic member is formed integrally with the operating lever 26, this may be constituted by another member having elasticity such as a metal leaf spring. Obviously, an equivalent effect is obtained.

Since the present invention is configured as described above, it has the following effects.

An intermediate portion is pivotally supported so as to be rotatable, an engaging and disengaging portion at one end is engaged and disengaged according to opening and closing of the opening and closing mechanism, and an engaging finger at the other end is engaged with the plunger and a pusher portion. By using the operating lever configured to engage with the operating button of the burnout prevention switch, a small and inexpensive voltage trip device that is easy to assemble can be obtained.

Further, a fixed spring stopper and a movable spring stopper which comes into contact with the fixed spring stopper are provided to hold the plunger spring, and a return spring is interposed between the step formed on the plunger and the movable spring stopper. Since the engaging finger portion of the operating lever is engaged with the plunger via the movable spring stopper and the return spring, the burnout prevention switch 24 can be operated even if the component dimensions of each portion vary. Can be switched reliably.

By forming the pusher portion of the operating lever with an elastic member capable of deforming by a predetermined amount, the burnout prevention switch 24 can be reliably switched in the same manner as described above even if there are variations in the dimensions of the parts. it can.

[Brief description of the drawings]

FIG. 1 is a partial side sectional view showing a relationship between a voltage trip device and a crossbar in an ON state of a circuit breaker according to Embodiment 1 of the present invention.

FIG. 2 is a partial side sectional view illustrating a voltage trip operation of the circuit breaker according to the first embodiment of the present invention.

FIG. 3 is a partial side sectional view showing a relationship between the voltage trip device and the crossbar when the circuit breaker according to the first embodiment of the present invention is in a trip or off state.

FIG. 4 is a partial side sectional view of a voltage trip device of a circuit breaker according to a second embodiment of the present invention.

FIG. 5 is a partial side sectional view showing a relationship between a voltage trip device and a plunger when a circuit breaker according to a second embodiment of the present invention is in a trip or off state.

FIG. 6 is a partial side sectional view of a voltage trip device according to a third embodiment of the present invention.

FIG. 7 is a perspective view showing a conventional voltage trip device for a circuit breaker.

FIG. 8 is a partial sectional side view showing an ON state of a circuit breaker incorporating a conventional voltage trip device.

FIG. 9 is a partial side sectional view showing a tripped or off state of a circuit breaker incorporating a conventional voltage trip device.

[Explanation of symbols]

14 movable contact, 15 fixed contact, 16 trip bar, 17 cross bar, 17a engagement projection, 20 voltage trip device, 21a release coil, 21c permanent magnet, 22 plunger, 22a push rod, 23 plunger spring, 24 burnout prevention switch, 24a operating button, 26 operating lever, 26a engaging finger piece, 26
b disengagement part, 26c push part, 26d push part, 28
Reset spring, 30 fixed spring stop, 31 movable spring stop, 32 return spring.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshiyuki Tanibe 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 5M030 AB00 FC10 XX04 XX08

Claims (3)

[Claims] A release coil provided opposite to the trip bar and excited by a signal voltage; a plunger slidably provided on a core of the release coil; Provided at one end of the core of the release coil, the plunger is suction-held when the release coil is not excited, and the suction-holding force of the plunger is reduced when the release coil is excited. A plunger spring configured to project the plunger toward the trip bar when the attraction and holding force of the permanent magnet is reduced, and a burnout prevention device connected in series to the release coil. The switch and the intermediate portion are pivotally supported so as to be rotatable, the engagement / disengagement portion at one end is engaged / disengaged with the movable contact according to the opening / closing operation of the opening / closing mechanism, and the engagement finger portion at the other end is connected to the plug. An operating lever configured to engage with an operating button of the burnout prevention switch while the pusher provided on the side of the engaging finger is engaged with the engaging finger; A reset spring for urging and rotating the operating lever in a direction in which the plunger is pressed against the permanent magnet, wherein when the circuit breaker is tripped or in an off state, the urging force of the reset spring engages the operating lever. When the finger piece presses the plunger against the permanent magnet, and the pusher turns off the burnout prevention switch, and the circuit breaker is on, the engaging finger responds to the operation of the opening / closing mechanism. One part is retracted from the plunger, and the pusher is released from the operation button of the burnout prevention switch to return the burnout prevention switch to ON. Voltage trip device of a circuit breaker according to claim. 2. A plunger is provided with a fixed spring stopper and a movable spring stopper that abuts the fixed spring stopper to hold the plunger spring, and between the step formed on the plunger and the movable spring stopper. 2. The circuit breaker according to claim 1, wherein a return spring is interposed, and the engagement finger portion of the operating lever is engaged with the plunger via the movable spring stopper and the return spring. Voltage trip device. 3. The voltage trip device for a circuit breaker according to claim 1, wherein the pusher of the operating lever is formed of an elastic member capable of deforming by a predetermined amount.