JPS59180925A - Device for indicating operation of breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a circuit breaker operation display device that indicates the operation to the outside when the circuit breaker trips by interrupting a fault current.

[Technical background of the invention]

Generally speaking, in a low voltage breaker, when the breaker cuts off the fault current and trips, the electrical circuit is opened. Therefore, when a trip occurs, there is no current, and especially when using an earth leakage breaker, the control power is taken from two of the three phases (/
The force S1 is also generally taken from the load side inside the breaker. For this purpose, the control power supply also has breaker power (
It disappears when it trips and the electrical circuit is opened. For this reason, most conventional circuit breakers use a solenoid or a permanent magnet as the operating indicator. In this solenoid or a release type solenoid using a permanent magnet, the energy consumption of the release type solenoid is small.

[Problems with background technology]

However, if a release type solenoid malfunctions due to shock or vibration when opening/closing a breaker, shock or vibration when triangulating, or a magnetic field when a breaker interrupts a large current such as a short circuit current, /1 There is a drawback.

[Purpose of the invention]

The present invention has been developed to eliminate the above-mentioned drawbacks, and its purpose is to create a circuit breaker that consumes 71% less energy, is strong against vibrations and shocks, and does not malfunction even with a large current magnetic field. An object of the present invention is to provide an operation display device.

[Summary of the invention]

In order to achieve the above object, the present invention is a breaker that opens, closes, and trips when current is applied, and detects accidents such as overcurrent, short circuit, leakage, open phase, and anti-phase as a trip, and trips the breaker. A shape memory alloy that returns to its original shape before deformation when it reaches a certain temperature is used as an operation display element to indicate what kind of accident caused the breaker to trip. A first element that heats the shape memory alloy to a deformation temperature μ using a signal current, and operates in conjunction with the operation of a mechanism catch of the breaker when the breaker trips.
link, and a second link that operates in conjunction with this first link.
and a third link that operates in conjunction with the second link and supports one end of the third link with an elastic member so as to apply force in one direction, and the shape memory alloy receives an operation signal. When the temperature exceeds the deformation temperature and returns to the shape before deformation, the display rod that has been defeated by the shape memory alloy will protrude from the cover of the breaker, and the third link will cause the display rod to protrude. The display bar is characterized in that the display bar can be reset by holding the display bar and resetting the breaker.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention shown in FIGS. 1 to 5 will be described. 1 and 2 are side views showing a configuration example of a circuit breaker to which the present invention is applied, with FIG. 1 showing the on state and FIG. 2 showing the trip state. In the figure, 1 is a cover, 2 is a case, 3 is an operating knob, 4 is a main spring, 5 is a current terminal, and 6 is a movable arm, which moves in conjunction with the on/off operation of the operating handle 3.

Further, 7 is a catch, which engages with the catch receiver 8 in the normal on-off state, and only when the fault current is cut off and trips, the catch 7 is released from the catch receiver 8 and the second
It will be in the position shown in the figure. On the other hand, 9 is the first link in the operation display device of the present invention, the details of which will be described later.When the breaker is not tripped (Fig. 1), it is held downward by the catch 7, and the breaker is held down by the catch 7. When it trips (Fig. 2), it is released from the catch 7, moves upward, and comes to rest.

3 and 4 are side views showing an example of the structure of the circuit breaker operation display device according to the present invention, in which FIG. 3 shows a state in which no operation is displayed or is reset, and FIG. 4 shows an operation display. This indicates the state in which the In the figure, 1 is a first link with a bracket <-19ζ, 21 is a pin, and the first link 9 is rotatable around this pin 21. Also, 22 is a second link. It is rotatable around a pin 23, one end of which engages with the first link 9, and the other end of which engages with a third lug 24.This third link 24 , one end is supported by a compression spring 25 so as to apply force in one direction, and the other end 27 is set to engage with the operating pin portion 32 of the micro switch 3. (It is a shape memory alloy that returns to its original shape before deformation when it reaches a certain temperature. It is wound into a coil below the display rod 28, and one end is supported by the frame 26, and the other end is the second end of the display rod 28. It is supported by the stepped portion 33.Furthermore, the display rod 28 is
After a certain period of operation, the display bar 28 is fixed by the frame 26 so that it does not come out from the surface of the cover 1 any more.

Figure 5 shows a breaker (earth leakage breaker) to which the present invention is applied.
FIG. 2 is a circuit block diagram showing a configuration example. In the figure b
MCR to MCT are main circuit contacts, C that detects main circuit current
TR to CTT are current transformers, 11 is a large current detection circuit, 12
13 is a voltage sensor circuit, 13 is a long-time circuit, 14 is a short-current circuit, 15 is an instantaneous circuit, 16.17 is a trigger circuit, and 18 is a display circuit, which is connected directly to the shape memory alloy 29 in FIGS. 3 and 4. A pulsed underflow is applied so that the temperature of the shape memory alloy is indirectly above the deformation temperature. In addition, DI and D2 are diodes, CI is a tripping coil, Z and T are zero-phase current transformers that detect the zero-phase current of the main circuit, 18 is an abnormal voltage absorption circuit, 19 is an amplifier circuit, and 20 is a rectifier/smoothing circuit. In the circuit, PT is a control transformer, PB is a test button for earth leakage test, and R is a test resistor for the earth leakage test circuit.

Next, the operation of the breaker operation display device of the present invention will be explained.

The operation display device having the above-mentioned configuration first displays the third
As shown, the first link 9 is pushed downward by the catch 7 of the circuit breaker shown in FIG.
The link 24 of is held in a fixed position. The shape memory alloy 29 is below the deformation temperature, and the indicator bar 28 is reset to become a deformation deaf (FIG. 3) under the deformation temperature μ.

Next, the operation of the operation display device will be described using, for example, an earth leakage operation display of an earth leakage breaker. In Fig. 5, when leakage current exceeds a certain level, zero-phase current transformer ZCT
The leakage current is detected and the leakage trigger circuit 17 is turned on through the amplifier circuit 19. At this time, the power output current from the control transformer RT passes through the rectifier and smoothing circuit 20, and further passes through the diode D2 to the tripping coil CI,
It flows through the display circuit 18 and trigger circuit 17, returns to the rectification and smoothing circuit 20, and returns to the control transformer RT. At this time, the tripping coil CI rotates the catch receiver 8 in FIG. opens counterclockwise (Figure 3).

The main contact MOR" MOT opens, and at this time, in the display circuit 18, the shape memory alloy 29 of FIGS. 3 and 4,
A pulsed direct current is applied directly or indirectly to the shape memory alloy 2.
9 is set to be higher than the deformation temperature. This results in
This shape memory alloy 29 returns to its original shape before deformation (fourth
As a result of the deformation, the indicator bar 28 comes out from the cover 1 and provides an operational indication that the breaker has tripped due to an electrical leakage. At this time, the first link 9 has the catch 7 disengaged from the catch receiver 8 (FIG. 2), the first link 9 has lost its holding force from the catch 7, and the compression spring 25 is The third link 24 is pushed to the left by the force, the second link 22 rotates counterclockwise, and the first link 9 also rotates counterclockwise. The third link 24 engages with the first stepped portion 34 of the indicator bar 28, and the other end 27 pushes the operating pin portion 32 of the microswitch 3. This microswitch 31 can be used when indicating an operation display far away from the breaker (the fourth
Figure) On the other hand, when the breaker is reset, the first II sink
Since the catch 7 is engaged with the catch receiver 8, it is rotated clockwise by the force.

The second link 22 is also rotated clockwise by the first link 9. The force of the second link 22 causes the third link 24 to move to the right in the figure against the force of the compression spring 25. As a result, the other end 27 of the third link 24 is disengaged from the operating pin portion 32 of the microswitch 31, and the engagement between the first step portion 34 of the display bar 28 and the third link 24 is also disengaged. 28 becomes free from the third link 24.

In this case, when an irreversible material is used as the shape memory alloy 29, when the shape memory alloy 29 becomes lower than the deformation temperature, the display bar 28 can be reset by pushing the display bar 28 downward. state (Figure 3). Furthermore, when a reversible material is used as the shape memory alloy 29, the indicator bar 28 automatically returns to the reset state when the shape memory alloy 29 falls below the deformation temperature (FIG. 3).

〔Effect of the invention〕

As explained above, according to the present invention, a shape memory alloy is used as the operation display element of the circuit breaker, which consumes less energy and is resistant to vibrations and shocks when opening/closing or tripping, and is a release type solenoid. Thus, a highly reliable breaker operation display device that does not malfunction due to large current magnetic fields can be provided.

[Brief explanation of drawings]

FIG. 1 is a side view showing the on state of the breaker to which the present invention is applied, FIG. 2 is a side view showing the tripped state, and FIG.
The figure is a side view showing an embodiment of the operation display device (7) of the present invention in the IJ upper set state, FIG. 4 is a side view showing an embodiment of the operation display state, and FIG. FIG. 2 is a circuit block diagram illustrating an application example. 7...catch, 9...first link, 22...
2nd link, 24...Third link, 25...Spring, 28...Display bar, 29...Shape memory alloy, 3...Micro switch. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 N Figure 5

Claims (2)

[Claims] (1) A circuit breaker that opens, closes, and trips when current is flowing. Trips include overcurrent, short circuit, leakage,
In devices that trip the circuit breaker by detecting accidents such as open phase or reverse phase, it is used as an operation display element to display what kind of accident caused the circuit breaker to trip, and returns to its original shape before deformation when a certain temperature is reached. Using a shape memory alloy, at the same time as the breaker is tripped, the shape memory alloy is heated above the deformation temperature by the operation signal current, and when the breaker is tripped, the breaker operates in conjunction with the operation of the breaker mechanism catch. a first link; a second link that operates in conjunction with the first link; and one end of the second link that operates in conjunction with the second link and has an elastic member at one end to apply force in one direction. and a third supporting link, and when the shape memory alloy reaches a deformation temperature or higher in response to an operation signal and returns to its pre-deformation shape, an indicator rod attached to the shape memory alloy protrudes from the cover of the breaker. and holding the display bar in a protruding state with the third link,
A circuit breaker operation display device, characterized in that the display bar can be reset by resetting the circuit breaker. (2) The breaker operation display device according to claim 1, wherein a microswitch is pressed at the tip of the third link.