JP5612189B1 - Impact detection device - Google Patents

Abstract

An impact detection device capable of detecting an impact generated with an operation of a circuit breaker with high accuracy is provided. An impact detection device (10) is provided in a mounting mechanism in which a casing 103 can be detachably mounted on a surface of a circuit breaker 30, and is propagated through the mounting mechanism. And a processing circuit for determining whether or not an impact has occurred and outputting the determination result. The mounting mechanism includes a cover cap 101 having a protrusion 102 formed in the vicinity of the center portion of the outer bottom surface thereof, and a magnet M provided in the inner space thereof. Further, the protruding portion 102 is penetrated so that a part thereof protrudes into the internal space of the housing 103, and the protruding end of the protruding portion 102 is joined to a part of the peripheral portion of the piezoelectric diaphragm P, thereby impact. Propagates. [Selection] Figure 2

Description

  The present invention relates to a technique for detecting an impact generated during operation of a circuit breaker with high accuracy.

In recent years, substation equipment has become a wide variety of equipment along with technological advances, and it is necessary to fully examine in advance inspection methods (test methods) and the like in order to carry out security operations.
For example, in the interlocking test (breaker interlocking test) between the protective relay and circuit breaker in the inspection test for high-voltage electrical equipment, safety is ensured by attaching test wiring to the high-voltage circuit and control circuit, and then removing the test wiring. However, it is necessary to perform complicated work. In addition, since it is a security service, there is a restriction on the time that can be spent on testing and inspection, and in these tests and inspections, high measurement accuracy (detection accuracy) is required.

  From the viewpoint of reducing the labor and time of work in such an interlock test, there is a circuit breaker operating time measuring device disclosed in Patent Document 1. In this circuit breaker operating time measuring device, a vibration sensor is detachably attached to the outer surface of the switchboard that houses the circuit breaker, the protective relay is activated, and the vibration generated during the operation of the circuit breaker is detected by the vibration sensor. Measure the operating time of the instrument. This eliminates the need for test wiring to the high-voltage circuit, eliminates work on the rear surface of the distribution board of the dangerous receiving and transforming equipment, ensures safety, and simplifies the test work.

  In addition, the protective relay / breaker operation detection device disclosed in Patent Document 2 can be used for the protective relay / breaker without electrical connection to the breaker even if the protective relay or breaker is covered with a cover. It is possible to measure the operation test and the operation time of the protective relay / breaker by detecting the operation vibration and the operation time of the protection relay / breaker.

JP 2009-148117 A Utility Model Registration No. 3146155

However, the detectors referred to as vibration sensors disclosed in Patent Document 1 and Patent Document 2 are general-purpose vibration sensors widely distributed in general as products intended to be fixed to devices. If the main body is modified so that such a vibration sensor for fixing can be repeatedly attached and detached, not only will the characteristics change, but also the time error produced by the sensor and the stability of detection cannot be maintained. That is, the configuration is not suitable for detecting the circuit breaker operation.
In the circuit breaker interlocking test, since the circuit breaker is operated to be interrupted continuously ten times or more, the test is performed so that the circuit is immediately turned on after the circuit breaking operation. Therefore, double vibration is generated in the test. For example, the vibration sensor may be subjected to a large vibration (or shock) and self-saturate, and it may take time to recover. As a result, there is a problem that a continuous circuit breaker interlocking test cannot be performed. In addition, the vibration sensor may deteriorate and fail due to large vibrations. Furthermore, the detectors referred to as vibration sensors disclosed in Patent Literature 1 and Patent Literature 2 are easily affected by microvibration that is unnecessary because a high amplification circuit is used for vibration detection. In addition, since the delay time error between the sensor, the amplifier circuit, and the output circuit is unknown, there remains a problem that it is impossible to detect the impact generated by the operation of the circuit breaker with high accuracy.

  The impact generated by the operation of the circuit breaker has a characteristic that its rising speed is high and it quickly attenuates. The specification of the protective relay includes an item (for example, JISC4602, operating time characteristic test) required to have an operating time of 50 [ms] or less. Further, the minimum resolution of the hour meter of the tester generally used in the circuit breaker interlocking test is 1 [ms]. Therefore, in a test item that requires high measurement accuracy, make (ON) from detection of an initial impact (initial impact or initial shock wave, which may be simply referred to as impact hereinafter) generated with the operation of the circuit breaker. That is, a high-speed and high-sensitivity detection device is required in which the time (delay time) required to output the detection result to the tester is less than 1 [ms], for example.

  The main object of the present invention is to solve the above-mentioned problems and to provide an impact detection device capable of detecting an impact generated during operation of a circuit breaker with high accuracy. Further, the present invention provides an impact detection device that minimizes a delay time from detection of an initial impact to output of a detection result and does not require a power source.

An impact detection device according to the present invention is an impact detection device that detects an impact that occurs during operation of a device, and includes a housing having a mounting mechanism that can be detachably mounted on the surface of the device, and an interior of the housing. Piezoelectric diaphragm that converts the impact transmitted through the mounting mechanism through the mounting mechanism into an electrical signal and outputs it, and the impact is generated based on the output electrical signal disposed in the internal space of the housing And a processing circuit that outputs the determination result, and the mounting mechanism includes a bottomed cylindrical body having a protrusion formed near the center of the outer bottom surface, A gap of a predetermined distance is formed between the outer bottom surface of the bottomed cylindrical body and the outer surface of the casing opposite to the bottomed cylindrical body. projecting into the internal space part of the protrusion with the deployment of the enclosure It is penetrating into the enclosure so that, and constituted by this protruding end of the protrusion is joined to the part of the peripheral portion of the piezoelectric vibrating plate so that the shock is propagated.
Thereby, an impact is applied from one direction to one point of the peripheral portion of the piezoelectric diaphragm, and as a result, the impact can be detected with high accuracy. In addition, since it can be configured as a sensor-integrated impact detection device including a piezoelectric diaphragm and a processing circuit, it is possible to achieve a reduction in size and weight.

In some embodiments, the piezoelectric vibrating plate, characterized in that it is deployed in the internal space of the inner surface and the non-contact state become like the casing of the housing in a state joined with the protruding end of the protrusion And Thereby, for example, the piezoelectric diaphragm can be made less susceptible to the influence of unnecessary vibration such as low frequency (or very low frequency) and minute vibration (fine vibration) related to 50, 60 [Hz] in a commercial power supply. . Therefore, the impact can be detected with high accuracy.

  In one embodiment, the mounting mechanism is provided in the casing in a state where an outer bottom surface of the bottomed cylindrical body and an outer surface of the casing opposed to the bottomed cylindrical body are separated from each other. Thereby, for example, it is possible to make the piezoelectric diaphragm less susceptible to unnecessary vibrations such as low frequency (or very low frequency) and fine vibration related to 50 and 60 [Hz] in a commercial power supply. Therefore, the impact can be detected with high accuracy.

  In one embodiment, the processing circuit is configured such that the output of the determination result is controlled by opening and closing a switch element, and the switch element is an nMOSFET. Thus, the processing circuit can be configured as a circuit that does not require a power source. In addition, since it is possible to suppress an increase in operation delay due to power consumption and loss of function due to power interruption, it is possible to detect an impact with high accuracy.

  In one embodiment, the attracting body is a magnet, and the magnet is in a state in which a mounting surface of the device when the mounting mechanism is mounted on a surface of the device and a surface of the magnet facing the device are separated from each other. It is formed in the size which becomes. Thereby, the area which a mounting mechanism and an apparatus contact can be made small. Therefore, it is possible to efficiently propagate the impact generated with the operation of the device toward the piezoelectric diaphragm.

  According to the present invention, it is possible to detect an impact generated during the operation of the circuit breaker with high accuracy. In addition, it is possible to configure a processing circuit for impact detection that minimizes the delay time until the detection result is output and does not require a power source.

The figure which shows the structural example at the time of using the impact detection apparatus which concerns on this embodiment for the circuit breaker interlocking | linkage test in a protection relay operation test. The schematic longitudinal cross-sectional view for demonstrating an example of a structure of the mounting mechanism which an impact detection apparatus has. The schematic longitudinal cross-sectional view for demonstrating the structural example of the mounting mechanism different from FIG. The block diagram which shows an example of a structure of the processing circuit of an impact detection apparatus. The figure which shows the result of having analyzed the actual operation characteristic of the impact detection apparatus. FIG. 5 is a block diagram illustrating a configuration example of a processing circuit different from FIG. 4.

Hereinafter, embodiments will be described with reference to the drawings. In the impact detection device of the present embodiment, the case where the impact generated when the circuit breaker operates (during the disconnection operation) is detected by a piezoelectric diaphragm (also referred to as a piezoelectric element or a piezoelectric sensor) using a piezoelectric element is used. An example will be described.
The piezoelectric diaphragm is, for example, a thin plate sensor processed into a rectangular or circular shape, and converts an external force applied to the surface (impact detection surface) of the piezoelectric diaphragm into a voltage or an applied voltage. Has a function to convert the power into force. Such a piezoelectric diaphragm is widely used, for example, as a sound component of an electronic buzzer, an actuator, or the like.
In addition, the resonance frequency (resonance point) of the piezoelectric diaphragm is generally about 1 [kHz] to 3 [kHz]. Among various piezoelectric diaphragms, for example, when the single resonance frequency is 6 [kHz] or more, the resonance speed is 167 [μs] or more. If such a piezoelectric diaphragm is used, it becomes possible to detect an impact (initial impact) with high accuracy.

  However, as a result of repeated studies by the present inventor, even when such a piezoelectric diaphragm is used, for example, the surface of the piezoelectric diaphragm is directly attached to the inner surface of the detection device, or the surface It has been found that when two or more are supported and attached, a delay in detection speed and a significant decrease in detection sensitivity occur. Further, it has been found that when a member made of a different material (for example, plastic) is interposed between the piezoelectric diaphragm and the inner surface of the detection device in the mounting, the resonance frequency is lowered. In the detection apparatus with the piezoelectric diaphragm attached in this way, the time (delay time) required from making an initial impact detection to making (ON), that is, outputting the detection result to the tester, should be less than 1 [ms]. And it becomes difficult to detect an impact with a measurement accuracy that satisfies the requirements of the test item. Hereinafter, an impact detection apparatus capable of solving these problems and detecting the impact generated by the operation of the circuit breaker with high speed and high sensitivity will be described.

FIG. 1 is a diagram illustrating a configuration example when the impact detection apparatus according to the present embodiment is used in a circuit breaker interlocking test (hereinafter, simply referred to as a test) in a protective relay operation test.
The impact detection device 10 shown in FIG. 1 is configured to be detachably mounted on the outer surface (mounting surface) of the circuit breaker 30 via a mounting mechanism (A shown in FIG. 1) described in detail later. In addition, a processing circuit for detecting an impact including a piezoelectric diaphragm P, which will be described later, is configured in the internal space of the casing (case 103, which will be described later) of the impact detection device 10, and the impact is transmitted via a mounting mechanism. Propagated to the piezoelectric diaphragm P. In the present embodiment, description will be given by taking as an example the case of using a piezoelectric diaphragm formed in a thin coin shape.

The protective relay 20 detects short-circuit faults, ground faults, etc. that have occurred in power plants, substations, transmission / distribution lines, and load facilities that constitute the power system, and controls for quickly separating the fault section from the power system. A signal (trip signal) is output to the circuit breaker 30.
The circuit breaker 30 is a switch for opening and closing the load current and the like of the power circuit / power device in a normal state and cutting off an accident current (for example, a short-circuit accident current) in cooperation with the protective relay 20. When the circuit breaker 30 interrupts the accident current, the load-side equipment is protected and the accident spread to the upstream side is prevented.

The tester 40 is operated by applying a test current, a voltage, or the like to the protective relay 20 and receives a detection result output from the impact detection device 10. Specifically, the protective relay 20 outputs a trip signal to the circuit breaker 30 when receiving a test current, a voltage, or the like from the tester 40. The circuit breaker 30 starts an opening operation upon receipt of a trip signal. The impact generated by the operation (breaking operation) of the circuit breaker 30 is propagated to the impact detection device 10 via the mounting mechanism, and then the detection result of the impact detection device 10 is output to the tester 40.

The tester 40 also measures the time (operating time) required for the circuit breaker 30 to operate after applying a test current, voltage, or the like to the protective relay 20. In this way, the circuit breaker interlocking test in the protective relay operation test is performed.
The description will be given assuming that the outer surface of the circuit breaker 30 is formed of a material (for example, iron) that can be attracted by a magnet.

FIG. 2 is a schematic longitudinal sectional view for explaining an example of the configuration of the mounting mechanism (A shown in FIG. 1) included in the impact detection device 10.
As shown in FIG. 2, the mounting mechanism of the impact detection device 10 includes a bottomed cylindrical cover cap 101 formed in a pan shape, and a protrusion formed near the center of the outer bottom surface of the cover cap 101. The magnet 102 which is an example of an adsorbent disposed in the internal space of the part 102 and the cover cap 101 is configured.
The cover cap 101 is a cover cap for the magnet M, and is formed using, for example, iron as a material. The magnet M is formed in a size and shape that can be arranged inside the cover cap 101 (internal space). Further, the magnet M has a distance L (for example, 0.5 [mm]) from the outer surface of the magnet M on the side facing the outer surface of the circuit breaker 30 (hereinafter, this surface is referred to as the upper surface of the magnet M). ). By combining the cover cap 101 and the magnet M formed in this way, the magnetic force is concentrated on the cover cap 101,
It is possible to generate stronger magnetic energy than in the case of the magnet M alone. That is, the cover cap 101 functions as a yoke portion in a so-called cap magnet. Further, the contact area between the mounting mechanism and the circuit breaker 30 when the impact detection device 10 is mounted on the circuit breaker 30 is reduced. Therefore, it is possible to efficiently propagate the impact generated by the operation of the circuit breaker 30 toward the piezoelectric diaphragm P. For example, even if the generated impact is small, it can be propagated toward the piezoelectric diaphragm P while minimizing the attenuation.

The protrusion 102 is a protrusion having a predetermined height (for example, 5 [mm]), and a part of the protrusion 102 is inserted into the housing 103 so as to protrude into the internal space of the housing 103 of the impact detection device 10. . The protruding end of the protruding portion 102 is joined to a part of the peripheral portion of the piezoelectric diaphragm P disposed in the internal space of the housing 103. Specifically, a point on the outer periphery of the protrusion 102 and a point on the outer periphery of the surface of the piezoelectric diaphragm P in contact with the protruding end (hereinafter referred to as the bottom surface of the piezoelectric sensor) are joined at a position where they overlap. . In addition, as shown in FIG. 2, compared with the bottom face of the piezoelectric diaphragm P, the protrusion surface of the protrusion 102 in contact with this has a sufficiently small area.

Thus, the protrusion 102 functions as a support member for supporting the impact detection device 10 in a state in which the impact detection device 10 is mounted on the circuit breaker 30, and the piezoelectric element disposed in the internal space of the housing 103. the diaphragm P, and also functions as a support member for supporting the inner surface and the non-contact state of the housing 103.
As shown in FIG. 2, the protrusion 102 has a distance H [mm] (for example, 0. 0 mm) between the outer bottom surface of the cover cap 101 and the outer surface (mounting surface) of the housing 103 facing the projection. 5 [mm]) is formed to form a gap. That is, the outer bottom surface of the cover cap 101 is separated from the surface of the housing 103 facing the cover cap 101.
Further, as shown in FIG. 2, the protrusion 102 has a predetermined distance between the bottom surface of the piezoelectric diaphragm P and the inner surface of the housing 103 facing the piezoelectric diaphragm P. Support. This predetermined distance is a distance (for example, 2 [mm]) such that the piezoelectric diaphragm P does not contact the inner surface of the housing 103 due to the propagated impact. That is, the piezoelectric diaphragm P is disposed in a non-contact state with the inner surface of the housing 103. As described above, gaps are formed between the outer bottom surface of the cover cap 101 and the surface of the housing 103 facing the cover cap 101 and between the bottom surface of the piezoelectric diaphragm P and the inner surface of the housing 103 facing the piezoelectric diaphragm P. In addition, the piezoelectric diaphragm P supported by the protrusion 102 is less susceptible to unnecessary vibrations such as low frequency (or very low frequency) and fine vibration related to 50 and 60 [Hz] in the commercial power supply. be able to.

In the mounting mechanism configured as described above, the impact F generated by the circuit breaker 30 is propagated to the piezoelectric diaphragm P via the cover cap 101 and the protrusion 102. That is, the impact F is applied to one point of the peripheral portion of the piezoelectric diaphragm P from one direction, and as a result, the impact can be detected with high accuracy. In addition, it is possible to output a stable and sufficiently high voltage (+ (plus) voltage) electric signal that provides practical sensitivity in the test.
The joining of the protruding end of the protruding portion 102 and the bottom surface of the piezoelectric diaphragm P is not limited to the above-described form. For example, the size of the protruding surface of the protruding portion 102, the material and shape of the protruding portion 102, and the bottom surface of the piezoelectric vibrating plate P Depending on the size, the detection characteristics of the piezoelectric diaphragm P, and the like, the bonding position suitable for impact detection can be appropriately adjusted.

FIG. 3 is a schematic longitudinal sectional view for explaining another configuration example of the mounting mechanism. In the mounting mechanism shown in FIG. 3, instead of the configuration of the mounting mechanism shown in FIG. 2 (cover cap 101, magnet M, protrusion 102), widely used cap magnets and screws (counter screws) are used. .
As shown in FIG. 3, the cap magnet is composed of a magnet formed in a ring shape and an iron cap (yoke), and the magnet is disposed in a recess of the iron cap.
As shown in FIG. 3, the countersunk screw penetrates the wall surface of the casing 103 in a state where the countersunk portion (screw head) is disposed in the internal space of the casing 103. As shown in FIG. 3, a part of the peripheral portion of the piezoelectric diaphragm P is joined to the upper surface of the dish portion. Specifically, it is joined at a position where one point on the outer periphery of the upper surface of the plate portion and one point on the outer periphery of the piezoelectric diaphragm P overlap. In addition, as shown in FIG. 3, compared with the bottom face of the piezoelectric diaphragm P, the upper surface of the dish portion has a sufficiently small area. 2, predetermined gaps are formed between the circuit breaker 30 and the magnet, between the cap magnet and the housing 103, and between the housing 103 and the piezoelectric diaphragm P, respectively. Has been.

In the mounting mechanism configured as described above, the impact F generated by the circuit breaker 30 is propagated from the yoke portion of the cap magnet to the screw and is transmitted to the piezoelectric diaphragm P. That is, the impact F is applied to one point of the peripheral portion of the piezoelectric diaphragm P from one direction, and as a result, the impact can be detected with high accuracy. In addition, it is possible to output a stable and sufficiently high voltage (+ (plus) voltage) electric signal that provides practical sensitivity in the test.
It should be noted that the bonding between the upper surface of the dish portion and the bottom surface of the piezoelectric diaphragm P can be appropriately adjusted so as to be a bonding position suitable for impact detection.

FIG. 4 is a block diagram illustrating an example of a configuration of a processing circuit of the impact detection device 10.
The internal space of the housing 103 of the impact detection device 10 shown in FIG. 4 includes a piezoelectric diaphragm P, a Zener diode ZD, a diode D1, a capacitor C1, a resistor R1, an nMOSFET (Q1), and an output terminal 104. A circuit is deployed. The output terminal 104 is connected to the operation detection cord of the tester 40.
The piezoelectric diaphragm P detects the occurrence of an impact of the circuit breaker 30. The Zener diode ZD is also called a constant voltage diode, and protects the nMOSFET (Q1) from overvoltage. The diode D1 rectifies an electric signal such as a current in one direction to prevent the occurrence of backflow. The capacitor C1 is a so-called passive element and shapes the waveform of the electric signal. The decay time constant in the processing circuit is determined by the types of the capacitor C1 and the resistor R1.

The nMOSFET (Q1) shown in FIG. 4 is a kind of switch element (semiconductor switch element) also called an n-type metal-oxide-semiconductor field-effect transistor. If no voltage is applied to the gate G, the nMOSFET (Q1) is electrically insulated because a p-type semiconductor having different properties is sandwiched between the drain D and the source S made of an n-type semiconductor. As a result, no current flows between the drain D and the source S, and the switch is turned off. When a voltage is applied to the gate G, free electrons are attracted to the channel region directly below the gate. As a result, a current easily flows and the switch is turned on. In this way, the nMOSFET (Q1) determines whether or not an impact has occurred (ON or OFF) based on the electrical signal output from the piezoelectric diaphragm P, and the determination result is tested via the output terminal 104 as the detection result of the impact. Is output to the device 40.

  Further, since the nMOSFET (Q1) is controlled by an electric field generated by an input voltage, a bias current is not required unlike a bipolar transistor, for example. Therefore, by adopting the nMOSFET (Q1), as shown in FIG. 4, the processing circuit of the impact detection device 10 can be configured as a circuit that does not depend on the power source. In addition, since the processing circuit does not require a power supply, an increase in operation delay due to power consumption or a loss of function due to power failure is suppressed.

In the impact detection device 10 configured as described above, a sufficiently high voltage output from the piezoelectric diaphragm P is applied to the gate G of the nMOSFET (Q1). Therefore, even if the operating time of the nMOSFET (Q1) and the delay of the operating time of other elements are included, the Make (ON) can be performed at a speed of 167 [μs] or more which is the resonance speed of the piezoelectric diaphragm P. Hereinafter, the verification results verifying these points will be described in detail.

FIG. 5 is a diagram illustrating a result of analyzing actual operation characteristics of the impact detection device 10. The analysis of the actual operation characteristics was verified using the impact detection apparatus 10 having the configuration described with reference to FIG. This verification uses a DSO (digital storage oscilloscope: manufactured by Tektronix).
FIG. 5A shows an analysis result when the actual operation characteristics are verified by directly applying an impact to the cap magnet yoke. The vertical axis is the voltage (detection point level: 4.00 [V]) when viewed from the front of the figure. ) And the horizontal axis represents time (25 [μs / DIV]). FIG. 5A shows a waveform indicating the delay time until Make (ON) on the upper side as viewed from the front, and a waveform indicating the shock wave detection time on the lower side. In this verification, an analysis result was obtained that the shock wave detection time was about 82 [μs], and the delay time to Make (ON) was about 15 [μs] (falling about 2 [μs]). That is, it can be seen that the combined delay time (total delay time) is about 100 [μs] at the maximum.

  FIG. 5B is an analysis result when the actual operation characteristics are verified when the distance from the impact generation point in the circuit breaker 30 to the cap magnet is assumed to be about 20 [cm]. The vertical axis indicates voltage (detection point level: 4.00 [V]), and the horizontal axis indicates time (50 [μs / DIV]). Specifically, the impact detection device 10 was mounted on an iron plate, and verification was performed by applying an impact at a distance of about 20 [cm] from the cap magnet. In this verification, an analysis result with a detection delay time of about 230 [μs] was obtained. This delay time is a value obtained by adding a propagation delay in the iron plate because the position where the impact is applied is separated from the cap magnet by about 20 [cm]. In addition, if the operation time delay is about 230 [μs], the delay time is less than 1 [ms] which is the minimum resolution of the tester (tester 40). Therefore, although depending on the performance of the tester itself, the probability that the time meter of the tester determines that the delay error is 0 [ms] is considerably high.

FIG. 5C shows the result of verifying the actual operating characteristics when the attenuation time constant of the processing circuit is 10 [ms]. The vertical axis is the voltage (detection point level: 4.00 [ V]), and the horizontal axis represents time (25 [ms / DIV]). FIG. 5C shows the waveform indicating the Make (ON) time on the upper side when viewed from the front, and the waveform of the shock wave (shock wave detection waveform) detected on the lower side.
For example, when the output of the detection result of the impact detection device 10 is instantaneous, the tester 40 may not recognize that the detection result has been received. Therefore, the make time (ON signal output time) of the nMOSFET (Q1) must be set to a time during which the tester 40 can reliably recognize that the detection result has been received. When the decay time constant of the processing circuit is 10 [ms], as shown in FIG. 5C, the duration of Make (ON) is about 40 [ms] and is completely OFF after about 95 [ms]. You can see what is being done.

As described above, in the impact detection device 10 of the present embodiment, the piezoelectric diaphragm P disposed in the internal space of the housing 103 is supported by the protruding end of the protrusion 102, and the outer bottom surface of the cover cap 101 and Gaps are formed between the surface of the housing 103 facing each other and between the bottom surface of the piezoelectric diaphragm P and the inner surface of the housing 103 facing this.
Thereby, the impact generated with the operation of the circuit breaker 30 can be detected with high speed and high sensitivity. Moreover, since the delay time is very small, it is possible to ensure measurement accuracy that satisfies the requirements of the test items. Further, by using the nMOSFET (Q1), a processing circuit that does not require a power source can be configured. As a result, it is possible to suppress the occurrence of an increase in operation delay due to power consumption and loss of function due to power failure.

  Further, in the impact detection device 10, the sensor (vibration sensor or the like) and the amplifying device main body are separate from each other as in a conventional detection device, and it is not necessary to connect them at the time of testing. Therefore, there is no concern about the occurrence of contact failure at the connection point for each test, or confirmation of turning on / off of the power supply before and after the test work. Thereby, the working efficiency can be improved.

  Note that the outer surface of the housing 103 can be covered with a cover having a high buffer absorption effect (for example, a silicon cover). Thereby, even if it is a case where the impact detection apparatus 10 is accidentally dropped, damage to the housing | casing 103 and an internal circuit can be suppressed to the minimum. Further, unnecessary vibration transmitted to the housing 103 can be suppressed. Furthermore, since the silicon cover is well adapted to the hand and makes it difficult to slip, it contributes to prevention of falling when the impact detection device 10 is attached or detached.

<Modification>
FIG. 6 is a block diagram illustrating another example of the circuit configuration of the impact detection device 10. The difference from the circuit described in FIG. 4 is that it includes a diode D2, a polarity matching diode D3, an LED for operation confirmation, a resistor R2, and a battery BAT3V (CR2032). Further, the source S of the nMOSFET (Q1) is grounded (GND) as shown in FIG. This will be described in detail with a focus on these differences. In addition, about the same structure as already demonstrated, while attaching | subjecting the same code | symbol, the description is abbreviate | omitted.

The operation confirmation LED is turned on when the impact detection device 10 detects an impact. Thereby, the user can easily confirm that the impact is detected by the impact detection device 10.
In addition, since the light emitted from the LED emits ultra-high luminance, the lighting can be easily confirmed even in an outdoor test. Further, when the user attaches the impact detection device 10 to the circuit breaker 30, the LED is lit for a moment due to the impact at the time of attachment. Therefore, the user who is an operator can easily confirm whether or not the impact detection device 10 has failed at the time of wearing.
The polarity matching diode D3 makes the Make (ON) polarity of the nMOSFET (Q1) bipolar. This eliminates the troublesomeness for the user to confirm the polarity match when connecting the operation detection code of the tester 40 to the output terminal 104.

  In the impact detection device 10 having such a circuit configuration, the user is freed from various confirmation operations, the mental burden is reduced, and more concentrated by the test. Therefore, it is possible for the user to proceed with work while ensuring higher safety.

  The embodiment described above is for explaining the present invention more specifically, and the scope of the present invention is not limited to these examples.

DESCRIPTION OF SYMBOLS 10 ... Impact detection apparatus, 20 ... Protection relay, 30 ... Circuit breaker, 40 ... Tester, 101 ... Cover cap, 102 ... Projection part, 103 ... Case, M ... magnet, P ... piezoelectric diaphragm.

Claims (4)

An impact detection device that detects an impact that occurs during operation of the device,
A housing having a mounting mechanism that can be detachably mounted on the surface of the device;
A piezoelectric diaphragm that is disposed in the internal space of the housing and converts the impact propagated through the mounting mechanism into an electrical signal and outputs the electrical signal;
A processing circuit that is disposed in the internal space of the casing and determines whether or not an impact has occurred based on the output electrical signal and outputs the determination result;
The mounting mechanism includes a bottomed cylindrical body having a protrusion formed in the vicinity of the center of the outer bottom surface thereof, and an adsorbent disposed in the internal space of the bottomed cylindrical body. It is arranged so that a gap of a predetermined distance is formed between the outer bottom surface of the body and the outer surface of the casing opposite to the body, and a part of the protruding portion protrudes into the inner space of the casing. And the protrusion of the protrusion is joined to a part of the peripheral portion of the piezoelectric diaphragm, whereby the impact is propagated.
Shock detection device. It said piezoelectric diaphragm is characterized in that it is deployed in the internal space of the inner surface and the non-contact state become like the casing of the housing in a state joined with the protruding end of the protrusion,
The impact detection apparatus according to claim 1. The processing circuit is configured such that the output of the determination result is controlled by opening and closing a switch element, and the switch element is an nMOSFET,
The impact detection apparatus according to claim 1 or 2 . The adsorbent is a magnet;
The magnet is formed in such a size that the mounting surface of the device when the mounting mechanism is mounted on the surface of the device and the surface of the magnet facing the device are separated from each other.
The impact detection apparatus according to any one of claims 1 to 3 .

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