JPH0864087A - Contact parting time delaying mechanism of circuit-breaker - Google Patents

Abstract

PURPOSE: To secure the operation of an auxiliary relay which is operated by the detecting signal of a tripping current, by extending the current-carrying time of the tripping current of a circuit-breaker. CONSTITUTION: An installing plate 12 is provided at the lower part of a trip shaft 27, and a driving shaft 10 is penetrated laterally to the installing plate 12. An oil dash pot 11 is installed to the installing plate 12, and the tip of the plunger 11a of the oil dash pot 11 is opposed to the head 10a of a driving shaft 10. A trip coil 29 is installed to the left end of the installing plate 12, and the armature 29a of the trip coil 29 is opposed to the left side surface of the head 10a of the driving shaft 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker opening time delay mechanism.

[0002]

The opening time of a vacuum circuit breaker is generally 20 ms.
Therefore, when an opening signal is input from a protective relay that detects a circuit abnormality, it is required to open the main contact in the shortest possible time to prevent the accident from spreading. When the vacuum circuit breaker is opened, its state is displayed on the door of the switchgear in which the vacuum circuit breaker is accommodated by the auxiliary contact of the vacuum circuit breaker.

However, as an exception, the current flowing in the trip coil that opens the vacuum circuit breaker is detected, the auxiliary relay is operated by this detection signal, and the contact circuit of the auxiliary relay displays the accident indication circuit. Or the alarm circuit may be activated.

In the vacuum circuit breaker and the auxiliary relay having such special specifications, if the time required for the operation of the auxiliary relay is equal to or longer than the energization time of the current flowing through the trip coil, the auxiliary relay Before the operation of the contact is completed, the trip current of the vacuum circuit breaker becomes zero, and the operation of the auxiliary relay may not be completed.

Then, despite the opening of the vacuum circuit breaker, the display state of the closed state of the vacuum circuit breaker, which is the state before the accident, is displayed on the display device. Therefore, in order to avoid such an erroneous display, a method of extending the energization time of the current flowing through the trip coil of the vacuum circuit breaker, that is, delaying the opening start time of the vacuum circuit breaker as a result is rarely used. There is adopted.

FIG. 4 is a view showing an example of a contact opening time delay mechanism of a conventional circuit breaker used for such an application, and is a front view showing a state in which a vacuum circuit breaker is turned on. Also, FIG.
4 is a partial sectional view of FIG. 4, and FIG. 6 is a partial perspective view of FIG.

In FIGS. 4, 5 and 6, a closing coil 34 indicated by a chain double-dashed line is laterally attached to an upper left portion of a side plate 33 of the vacuum circuit breaker indicated by a chained line. An armature 34a indicated by a chain double-dashed line is loosely fitted from the right side to a spool (not shown) of the axis of the closing coil 34, and the right end of the armature 34a projects from the right end of the closing coil 34 to the right side. The armature protruding from this input coil 34
A trapezoidal return spring is inserted at the right end of 34a.

An operation button holder 36 is fixed to the right side of the closing coil 34. In the operation button holder 36, a closing button 35A is provided on the upper side from the right side and a tripping button 35B is provided on the lower side.
The left end of A is opposed to the right end of the armature 34a described above with a predetermined gap.

The front end of the trip shaft 27 projects from the side plate 33 below the trip bodbin 35B. The left side surface of the front end of the trip shaft 27 is processed into a flat shape, and the processed surface is bent in a convex shape and the upper portion thereof is provided with a trip button 35.
The right side surface of the central portion of the paddle 27a opposite to the left end of B contacts and is fixed to the trip shaft 27 by a pair of bolts 27b.

On the left side of the trip shaft 27, a trip unit plate 32 is fixed to the side plate 33 with bolts. At the left end of the trip unit plate 32, a coil mounting plate 29a bent in an L shape is mounted.

The left end of the trip coil 29 is fixed to the right side surface of the coil mounting plate 29a. The spool (not shown) at the axial center of the trip coil 29 has an armature.
29b is loosely fitted from the right side, and the right end of this armature 29b is opposed to the upper portion of the above-mentioned paddle 27a located at this right end with a predetermined gap.

On the left side of the trip shaft 27, a pin 37 is provided so as to project from the trip unit plate 32, and on the right side of the lower part of the pin 37, a pin 38 whose right side is in contact with the lower left side of the paddle 27a.
Is erected. Of these, a torsion spring 37a is preliminarily loosely fitted to the pin 37.
The right end of a is locked while pressing the left side surface of the pin 38.

On the other hand, the left end of the torsion spring 37 has a pin 37.
The catch 31 is swingably attached to the tip of the catch 31 and is locked to the upper right side of the center of the catch 31 described below. Therefore, a counterclockwise torque about the pin 37 is applied to the catch 31 by the restoring force of the torsion spring 37a.

At the right end of the catch 31, a pin 31b is provided so as to project rearward. The right side surface of the pin 31b is opposed to the lower left side surface of the paddle 27a described above with a predetermined gap by the counterclockwise torque applied to the catch 31 by the torsion spring 37.

An arcuate groove is formed in the center of the catch 31 on the slightly left side.
31d is formed vertically by pressing. The tip of the pin 39 is loosely fitted to the lower end of the groove 31d, and the base end of the pin 39 is fixed to the trip unit plate 32. Catch 31
A pin 31e is projectingly provided at the center of the lower part of the.

At the left end of the catch 31, a claw portion 31c is formed at a right angle to the horizontal lower surface. The lower surface at the tip of this claw portion 31c is a vacuum cutoff projecting to the left side of the pin 39 of the trip unit plate 32. The tip of the trip shaft 30 of the container comes into contact with the right end of the upper surface of the half moon, and is pressed against the upper surface of the half moon by the counterclockwise torque by the torsion spring 37 described above.

On the left side surface of the trip shaft 30, a partial vertical surface is formed at the rear of the above-mentioned half moon, and the lower end of the strip-shaped paddle 30a is fixed to this vertical surface by a bolt (not shown). There is. The upper end of the paddle 30a is opposed to the left end surface of the armature 29b loosely fitted in the trip coil 29 with a predetermined gap.

A torsion spring 30b is loosely fitted to the base of the trip shaft 30. This torsion spring 30b
One end of the paddle 30a is locked by the paddle 30a to maintain the paddle 30a in a vertical state, and the other end of the toshin spring 30b is fixed to the coil mounting plate 29a.

On the lower right side of the side plate 33, an end of a main trip shaft 39 of the vacuum circuit breaker is provided so as to penetrate therethrough. At the tip of the main trip shaft 39, the base ends of a pair of arms 40A and 40B are fixed. Has been done.
A pin 41a is provided at the tip of each of the arms 40A and 40B, and a stopper 41 made of a hexagonal rod is attached to the pin 41a.
Has been inserted.

In the conventional circuit breaker opening time delay mechanism configured as described above, when the trip coil 29 is excited, the armature 29 loosely fitted in the trip coil 29.
b is driven leftward and pushes the paddle 30a located on the left side of the trip coil 29. Then, the trip shaft 30, which fixes the lower end of the paddle 30a, oscillates counterclockwise, and the catch 31 in which the tip claw portion 31c is locked to the half-moon portion at the tip of the trip shaft 30 is a torsion spring.
The torque generated by 37a causes the pin 37 to swing in the counterclockwise direction.

By the swing of the catch 31, the catch 31 swings by a predetermined angle by the pin 39 loosely fitted in the groove 31d of the catch 31. On the other hand, a pin 31e protruding from the lower center of the catch 31 pushes a stopper 41 which is placed below the pin 31e, and drives the arms 40A and 40B counterclockwise via the pin 41a.

When the arms 40A and 40B swing counterclockwise, the main trip shaft to which the arms 40A and 40B are fixed is fixed.
39 is also driven counterclockwise, and the main contact (not shown) of the vacuum circuit breaker opens. When the main contact of the vacuum circuit breaker is opened, the exciting current of the trip coil 29 is cut off.

That is, the trip coil 29 is excited,
Even if the armature 29b is driven, the main trip shaft 39 is not directly driven. Therefore, the rotation of the main trip shaft 39 is delayed by the time required for the trip shaft 30 and the catch 31 to swing, and the main contact is opened. It takes longer time, trip coil
By extending the energization time of the exciting current flowing in 29, the above-mentioned auxiliary relay is reliably operated during this period.

Note that the tripping operation of the circuit breaker by manual operation is performed by pressing the tripping bodan 35B.
Push the upper part of 27a to the left and swing the pin 27 counterclockwise. When the paddle 27a swings counterclockwise, the upper portion of the paddle 27a swings counterclockwise.
By pushing the armature 29a of the trip coil 29 at the upper part of the paddle 27a, as described above, the paddle 30a is pushed at the left end of the armature 29a to swing the trip shaft 30 counterclockwise, and the catch 31 is also turned counterclockwise. Then, the main tripping shaft 39 is driven via the pin 31e to open the main contact.

[0025]

However, in the circuit breaker opening time delay mechanism constructed as described above, the trip coil 29 and the armature of the trip coil 29 are provided.
The paddle 30a, the trip shaft 30, and the catch 30 which are installed between the armature 29a and the main trip shaft 39 in order to drive the main trip shaft 39 that finally opens the main contact by the operation of 29b. Due to 31, pins 39, 38, 31e, etc., the number of parts that make up the circuit breaker opening time delay mechanism increases and becomes complicated, and it not only takes time to assemble and adjust dimensions between parts, However, due to the increase in the number of parts, the reliability such as operation and life may decrease. Therefore,
An object of the present invention is to provide an opening time delay mechanism of a circuit breaker which is easy to assemble and can delay the opening time with certainty.

[0026]

SUMMARY OF THE INVENTION The present invention provides a drive shaft that is driven by the armature of a trip coil of a circuit breaker and that includes delay means that engages the drive shaft to reduce the drive speed of the drive shaft. It is characterized by being adjacent to the drive shaft.

[0027]

With the drive shaft whose moving speed is reduced by the delay means, the rocking start time of the trip shaft is delayed,
According to the delay of the swing time of the trip shaft, the opening start time of the main contact of the circuit breaker is also delayed.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a circuit breaker opening time delay mechanism of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an opening time delay mechanism of a circuit breaker according to the present invention, showing a state in which a circuit breaker corresponding to FIG. 5 shown in the prior art is turned on.
FIG. 2 is a view showing a state in which the contact opening time delay mechanism of the circuit breaker shown in FIG. 1 is operated and the trip shaft is operated, and FIG. 3 is a partial perspective view of FIG. The same parts as those in FIGS. 4, 5 and 6 are designated by the same reference numerals and the description thereof will be omitted.

In FIGS. 1 and 3, a mounting plate 12 bent in a substantially Z shape is fixed to the side plate 33 with four bolts 12a at the lower portion of the trip shaft 27 protruding from the side plate 33 of the circuit breaker. Has been done.

The right end of the trip coil 29 is attached to the left side surface of the left end of the mounting plate 12. The right end of the armature 29a loosely fitted to the axial center of the trip coil 29 is loosely fitted in a guide hole 12b formed at the center of the left end of the mounting plate 12. At the left end of the armature 29a, a snap ring 29
d is inserted and the right side of this retaining ring 29d and the trip coil
A trapezoidal non-linear characteristic return spring 29c shown in FIGS. 1 and 2 is inserted between the left end face of 29 and 29.

A shaft portion 10c of the drive rod 10 penetrates left and right through a central portion 12c of the mounting plate 12. On the left side surface of the disk-shaped head 10a provided at the left end of the drive shaft 10, the right end of the armature 29a loosely fitted to the axial center of the trip coil 29 is opposed to the left end with a slight gap.

The right end of the drive shaft 10 is opposed to the lower left side surface of the paddle 27a with a predetermined gap. In the middle of the drive shaft 10, a retaining ring 10b is inserted on the left side inside the central portion 12c of the mounting plate 12, and a return spring is inserted between the right side surface of the retaining ring 10b and the right inner surface of the central portion 12c. The compression shaft 13 is loosely fitted on the drive shaft 10.

On the lower left side surface of the central portion 12c of the mounting plate 12,
A hexagonal flange portion formed at the center of the oil dash pot 11 is attached. Plunger 11 protruding to the left from the flange of this oil dashpot 11
The left end of a is opposite to the lower right side surface of the head 10a at the left end of the drive shaft 10 with a predetermined gap.

In the circuit breaker opening time delay mechanism configured as described above, when the trip coil 29 is excited,
The armature 29a is attracted to compress the return spring 29c and move it to the right. Then, the right end of the armature 29a presses the center portion of the left side surface of the head 10a at the left end of the drive shaft 10 to move the drive shaft 10 to the right as shown in FIG.

With the movement of the drive shaft 10 to the right, the return spring 13 is compressed, and the right end of the drive shaft 10 is moved to the paddle.
The lower left side surface of 27a is pressed to swing the paddle 27a counterclockwise about the trip shaft 27. When the trip shaft 27 swings to release the engagement with the trip catch (not shown) engaged with the trip shaft 27, the main trip shaft shown in FIG. 6 swings counterclockwise. , The vacuum circuit breaker is opened.

During the opening operation, when the head 10a at the left end of the drive shaft 10 starts to move to the right by the armature 29a, the plunger 11a of the axial center of the dashpot 11 which is opposed to the lower right of the head 10a. The left end is pressed by the head 10a.

Then, since the moving speed of the drive shaft 10 is reduced as the plunger 11 moves to the right, the time required to move the trip shaft 27 becomes long,
It is possible to delay the time until the opening start of the vacuum circuit breaker.

Therefore, the excitation time of the auxiliary relay can be extended, the auxiliary relay can be operated reliably, and the presence or absence of the opening of the vacuum circuit breaker can be accurately displayed on the display device.

In the above embodiment, the oil dash pot 11 is used in order to delay the operation of the drive shaft 10, but the pneumatic dash pot may be used.
Furthermore, a compression coil spring may be employed in which the repulsive force increases non-linearly as the compression ratio increases.

[0040]

As described above, according to the present invention, adjacent to the drive shaft driven by the armature which is moved by the excitation of the circuit breaker trip coil, the drive shaft is engaged with the drive shaft to reduce the drive speed of the drive shaft. By providing a delaying means for delaying the start of swinging of the trip shaft, and by delaying the start of swinging of the trip shaft, the start of swinging of the trip shaft of the circuit breaker is delayed, so that assembly is easy and opening is easy. It is possible to obtain a circuit breaker opening time delay mechanism capable of reliably delaying the pole time and reliably operating the auxiliary relay.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a contact opening time delay mechanism of a circuit breaker of the present invention.

FIG. 2 is a diagram showing an operation of a contact opening time delay mechanism of the circuit breaker of the present invention.

FIG. 3 is an enlarged perspective view showing a main part of FIG.

FIG. 4 is a diagram showing an example of a contact opening time delay mechanism of a conventional circuit breaker.

5 is a partial cross-sectional view of FIG.

6 is an enlarged perspective view showing the main part of FIG.

[Explanation of symbols]

10 ... Drive shaft, 11 ... Oil dash pot, 12 ... Mounting plate,
13, 29c… Return spring, 27… Trip shaft, 27
a ... paddle, 29 ... trip coil, 33 ... side plate, 34 ... closing coil, 35A ... closing button, 35B ... trip button, 36 ...
Operation button holder.

Claims (3)

[Claims] 1. A drive shaft driven by an armature of a trip coil of a circuit breaker, and a paddle that oscillates by the movement of the drive shaft to swing together to unlock a trip shaft of the circuit breaker. A circuit breaker opening time delay mechanism comprising a trip shaft for opening the circuit breaker, and a delay means for engaging with the drive shaft to reduce the moving speed of the drive shaft. 2. The opening time delay mechanism of a circuit breaker according to claim 1, wherein the delay means is a fluid dashpot. 3. A circuit breaker opening time delay mechanism according to claim 1, wherein the delay means is a coil spring having a non-linear characteristic.