JPH02265128A - Open circuit abnormality diagnosis device of breaker operation mechanism - Google Patents

Abstract

PURPOSE:To carry out maintenance and inspection before nonconformity occurs by fixing a stress gauge in a main shaft to detect a torque as operating force and an open circuit operating time, and giving an alarm comparing it with the standard open circuit operating time. CONSTITUTION:The device is constituted of a strain gauge 1 to detect a strain of a main shaft, a strain amplifier 2 to amplify this detected strain, a low-pass filter 3 to remove a high frequency component contained in this amplified strain waveform, and a detector for an open circuit operating time 4 according to an output of this low-pass filter 3. This detector for open circuit operating time 4 compares an open circuit operating time with a standard open circuit operating time, and gives an alarm when the open circuit operating time becomes longer than the standard open circuit operating time. Thus, it is possible to easily carry out maintenance and inspection by detecting in advance a symptom indicating an open circuit trouble which results from an increase of a frictional force of the operating mechanism of a breaker.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an open circuit abnormality diagnosing device for a breaker operating mechanism.

(Prior Art) Conventionally, as an example of a breaker operating mechanism, there is one constructed as shown in the perspective view of FIG. Figure 6 shows vacuum valve 3
1 is a side view showing a closed circuit standby state when the circuit is open, and FIG. 7 is a side view showing a state in which the vacuum valve 31 is in a state immediately after the circuit is closed. In the state shown in Fig. 6, the breaker (vacuum valve 31)
As soon as the power to the control circuit is turned on, the motor 6 rotates, and the rotation is transmitted to the motor shaft 7, gear 8, gear 9, and camshaft 10, and the closing spring 11 connected to the camshaft 10 is stored. to strengthen In the closing operation, when the closing catch 12 is driven by the closing shaft 15 using the closing coil 13 or the closing button 14, the closing catch 12 is disengaged from the roller 1B, and the closing cam 17 to which the roller 16 is fixed is moved by the spring force of the closing spring 11. By rapidly rotating clockwise around the camshaft 10 and pushing and moving the pins 18, the pins 18, 19, . 20
The links 2], 22.23 connected by the link 2], 22.23 are moved, and the main shaft 24 fixed to the link 23 is rotated clockwise. When the main shaft 24 rotates clockwise, the rotational force is transmitted from the link 25 fixed to the main shaft 24 to the link 26, which loads the wipe spring 27 and moves the lever 28 downward. . The lever 28 moves upward on the opposite side of the pin 29, moving the vacuum valve 3 upward through the rod 30 and closing the electric circuit. When the vacuum valve 31 is closed, the input cam 17, the input catch 12, the pins 18, 19, 20, and the links 21, 22
．． 23. The state of the main shaft 24 is as shown in FIG.

Thereafter, only the input cam 17 rotates, and the power storage operation is performed by the motor 6 while maintaining the closed circuit state until the roller 16 on the input cam 17 rides on the input catch 12.

The circuit opening operation is performed by tripping the tripping catch 32 and tripping the coil 33.
Alternatively, when the trip button 34 is driven by the trip shaft 35, the closing cam 17 rapidly rotates the main shaft 24 counterclockwise by the spring force of the trip spring 36, and Move the lever 28 connected upwards and release the pin 29.
On the opposite side, the lever 28 is moved downward, and the vacuum valve 31 is moved downward via the rod 30, thereby opening the electric circuit. At the same time, the main shaft 24
counterclockwise rotation of link 21. , 22.23
moves as shown in FIG. 6 and becomes the first open circuit state.

(Problem to be Solved by the Invention) As described above, the breaker operating mechanism section
and pin 18, pin 18 and link 21.22, motor 6
, the contact sliding part is connected to the shaft 7 and the link 37 (one end is connected to the trip catch 32 by a pin 39, and the other end is connected to the pin 19 connecting the link 21.degree. 38). In many cases, the frictional force of these contact sliding parts increases due to deterioration of the grease used as a lubricant or lack of oil film, microscopic deformation, contamination of foreign matter, etc., and the frictional force exceeds the opening force of the operating mechanism. When this happens, a problem occurs in which the circuit does not open when the circuit is opened. As a symptom of the problem, a phenomenon occurs in which the opening operation time becomes longer.

It is an object of the present invention to provide an open circuit abnormality diagnosis device that can detect in advance signs of an open circuit failure due to an increase in the frictional force of the operating mechanism of a circuit breaker, and can carry out maintenance and inspection at an early stage. .

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention stores the rotational energy of a motor, etc. in a spring, and applies this stored energy to the main shaft via a cam, catch, pin, link, etc. In this breaker operating mechanism that opens a circuit breaker using the rotational driving force of the main shaft, a strain gauge is attached to the main shaft to detect the axial torque generated in the main shaft, and the breaker opening is determined from this axial torque. The operating time and the standard opening operating time are compared by the comparison means, and when the comparison difference exceeds a predetermined value, the alarm means generates an alarm.

(Function) According to the present invention, in the breaker operating mechanism, a strain gauge is attached to the main shaft and the operating force is used as a sign of a circuit-opening failure due to an increase in frictional force or an increase in the circuit-opening operation time. By detecting the current, the circuit-opening operation time can be detected, and if this circuit-opening operation time is longer than the standard circuit-opening operation time, an alarm is issued, so maintenance and inspection can be carried out before circuit-opening problems occur.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of the present invention,
A strain gauge 1 that detects the strain on the main shaft 24 shown in FIG. 5, a strain amplifier 2 that amplifies the strain detected by the strain gauge 1, and a high-frequency component included in the strain waveform amplified by the strain amplifier It is comprised of a low-pass filter 3 for removal, and an open-circuit operation time detection device 4 having the following mechanism based on the output of the low-pass filter 3.

This circuit-opening operation time detection device 4 compares the circuit-opening operation time T1 shown in FIG. 2 with the standard opening operation time TO, and issues an alarm when the circuit-opening operation time TI becomes longer than the standard opening operation time TO. It is composed of a detection device 4.

Four strain gauges 1 are prepared, two of which are arranged at an angle of 90 degrees as shown in FIG. 5, and the strain gauge 1 is at an angle of 45 degrees with respect to the axis of the main shaft 24. Attach it like this.

Then, install the remaining two strain gauges 1 from the positions of the two strain gauges that were already installed.
Attach it in the same way at a different position. A total of four strain gauges installed in this way are connected in order so as to be in the direction of the next strain gauge or in the opposite direction to the previous strain gauge to form a bridge circuit.

In this way, rotation of the main shaft 24 will twist this axis, resulting in maximum strain at 45 degrees to the axis. From this strain, the torque as the operating force can be measured.

The strain detected by the strain gauge 1 is amplified by the strain amplifier 2, and the high frequency component is removed by the robust filter 3 to prevent errors.

The measured torque mentioned above has a waveform as shown in FIG.

Part a is the torque waveform when the vacuum valve 31 closes, and part b
3 is the torque waveform when the vacuum valve 31 is opened.

Now, due to an increase in the frictional force of the operating mechanism, the circuit-opening operation time T1 changes to a longer period like the standard circuit-opening operation time TO. This standard opening operation time TO and opening operation time T
I is compared by the opening operation time detection device 4, and if the opening operation time T1 is longer than the standard opening operation time TO, the buzzer B
The purpose is to issue a warning using Z and carry out maintenance and inspection at an early stage.

Although the standard opening operation time TO is approximately 35 m5 ec in the actual vacuum valve 31, it is set to 40 m5 ec in consideration of variations.

FIG. 3 is a circuit diagram for explaining the specific structure of the opening operation time detection device 4, and FIG. 4 is a time chart for explaining the operation of FIG. The output signal SO of the low-pass filter 3 is input to an operational amplifier 40a and an inverting amplifier 41. When the signal SO input to the operational amplifier 40a reaches a voltage VO that is slightly lower than the voltage equivalent to the torque applied to the main shaft when the circuit is closed, the signal SO is switched to Sl.
Generates a voltage of The voltage of Sl is set to about +5v.

The voltage of Sl is then applied to one-shot multivibrator 4.
2a and 42b. The output signal of the one-shot multi-by-break 42a is always ON, and when the open circuit signal S1 is input, it becomes OFF, and when the standard opening operation time reaches 40 m5ec, it becomes O again.
The output signal of the one-shot multivibrator 42b is in the N state, and the output signal of the one-shot multivibrator 42b, which is input as the signal S2 to the next 0NAND open circuit 43, is always ON, and turns OFF only for a very short time when the signal S1 at the start of opening is input. This time is about 10 μSQQ, and is input to the next flip-flop circuit 44 as a signal S3.

On the other hand, the No. 15 SO input to the inverting amplifier 41 is output as a signal S4 with the polarity inverted, and then the operational amplifier 40
b. The output signal S5 of the operational amplifier 40b is always ON, turns OFF when the voltage of the signal S4 rises from 0 to voltage V4, and turns ON again when the voltage of the signal S4 decreases to V4. Become. The voltage of S5 is about +5v.

The signal of S5 is then sent to the one-shot multivibrator 42c.
The output signal S6 is always ON, and the output signal S6 is always ON.
When the signal changes from the OFF state to the ON state, it remains OFF for a very short time.

This time is about 10 μsec. The signal S6 detects the end of the open circuit, and is then input to the flip-flop circuit 44.

In the flip-flop circuit 44 , a signal S 7 is generated from the OFF state to the ON state during the opening operation time of the circuit breaker based on the signal S 3 at the start of opening and the signal S 6 at the end of opening, and is input to the NAND circuit 43 . The standard opening operation time signal S2 and the actual opening operation time signal S7 of the circuit breaker are input to the NAND circuit 43, and if the opening operation time signal S7 is longer than the standard opening operation time signal S2, it is output. The signal S8 changes from a normally ON state to an OFF state for a time longer than the standard opening operation time.

The signal S8 is input to the flip-flop circuit 45 and is inputted to the buzzer 46 as a sustained signal S9 to generate an alarm. The switch 47 is always OFF and turned ON when the buzzer 46 is to be stopped. Also, if the wipe load by the wipe spring decreases to VO shown in Figure 4 for some reason when the circuit breaker is kept closed for a long time,
Operational amplifier 40? By connecting the output side of I and the input side of the buzzer 46, an alarm can be issued.

According to the embodiment of the present invention described above, the strain gauge 1 is attached to the main shaft 24 of the operating mechanism of the breaker,
By detecting the torque as the operating force, the circuit-opening operation time can be detected, and by comparing it with the standard circuit-opening operation time, it can be determined whether the frictional force of the operating mechanism has increased, allowing early maintenance before circuit-opening problems occur. Inspections can be carried out.

〔Effect of the invention〕

As described above, according to the present invention, a strain gauge is installed on the main shaft, since signs of circuit opening failure due to increased friction in the operating mechanism of the circuit breaker are expressed as an increase in circuit opening operation time. By detecting the torque as the operating force, it is possible to detect the opening operation time, and if it is longer than the standard opening excitation time, an alarm will be issued.
It is possible to provide an open-circuit abnormality diagnosis device for a breaker operating mechanism that can perform maintenance and inspection before an open-circuit failure occurs.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a schematic configuration of the present invention, FIG. 2 is a diagram showing torque waveforms when the vacuum valve is closed and opened,
3 is a diagram showing the circuit opening time detection device in detail in the configuration diagram of FIG. 1, FIG. 4 is a time chart 1 to explain the operation of the circuit opening time detection device of FIG. 6 is a perspective view of the operating mechanism of the breaker to which the present invention is applied;
The figure is a side view of the operation mechanism of the circuit breaker in the closed circuit standby state when the vacuum valve in Figure 5 is open, and Figure 7 is the side view of the operation mechanism of the circuit breaker in the state immediately after the vacuum valve in Figure 5 is closed. FIG. Toss strain gauge 3...Low pass filter 4...Open circuit operation time detection device, +8. 19. 20...pin, 21,
22. 23... Link, 24... Main shaft, 32... Trip catch, 33... Trip coil, 34... Trip button, 35... Trip shaft, 36... Trip Spring. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 2 B Funeral diagram Funeral diagram

Claims (1)

[Claims] A breaker operation in which the rotational energy of a motor, etc. is stored in a spring, this stored energy is applied to the main shaft via a cam, catch, pin, link, etc., and the breaker is opened by the rotational driving force of this main shaft. In the mechanism, a strain gauge is attached to the main shaft to detect the shaft torque generated in the main shaft, and the breaker opening operation time determined from this shaft torque is compared with the standard opening operation time using a comparison means, and the comparison difference is calculated. An open circuit abnormality diagnostic device for a breaker operating mechanism that generates an alarm using an alarm means when the value exceeds a predetermined value.