JPH09281138A - Angular velocity sensor - Google Patents

Abstract

(57) Abstract: An object is to provide an angular velocity sensor having a failure diagnosis function. An angular velocity including a driving unit for stably vibrating a vibrating unit of a sensor element having a vibrating unit and a detecting unit for detecting an angular velocity, and a detecting unit for detecting an angular velocity from the detecting unit of the sensor element. In the sensor, a self-diagnosis signal at the time of failure is obtained by electrically adding a signal synchronized with the drive signal of the drive means to a stage preceding the synchronous detector constituting the detection means.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an angular velocity sensor having a self-diagnosis function.

[0002]

2. Description of the Related Art For example, a tuning fork type angular velocity sensor is provided with a detection plate at the tip of both drive plates of a tuning fork type drive section in a direction orthogonal to the drive plates, and the angular velocity is kept constant while the drive plates are constantly driven. When added, the angular velocity is detected by the output from the detection plate which vibrates in the opposite directions in response thereto.

[0003]

A problem with the conventional angular velocity sensor is that, after the sensor is activated, when a failure occurs in a component, the failure is notified to the outside or a criterion for determining the failure from the outside. It was not equipped with the function to have the information that becomes.

An object of the present invention is to enable the use of a highly reliable angular velocity sensor by enabling external detection of a state in which a part of it is damaged and normal detection operation is not possible. It is what

[0005]

To achieve this object, the angular velocity of the present invention supplies a drive signal to a sensor element having a vibrating section and a detecting section for detecting the angular velocity, and a vibrating section of the sensor element. A driver circuit and a monitor circuit to which a monitor signal from the sensor element is added are included, and the output of the monitor circuit is applied to the driver circuit via an AGC circuit to stably drive and vibrate the vibrating portion of the sensor element. The driving means includes a charge amplifier to which the output from the detection unit of the sensor element is added, and a synchronous detector to which the output of the charge amplifier is added via a bandpass filter, and the output of the bandpass filter to the driving means. Detecting means for detecting and outputting an angular velocity signal in synchronism with the drive signal from Detecting an abnormality of said sensor element by applying the preceding stage from the synchronous detector composing the is obtained a self-diagnosis means for outputting a self diagnosis signal.

With the above configuration, a monitor circuit, which is a constantly stable feedback signal from the tuning fork for always stabilizing the vibration of the vibrating section, is added to the preceding stage of the synchronous detector, thereby providing a drive circuit for driving the sensor element. It becomes possible to detect anomalies in many components that make up the angular velocity sensor including a detection circuit such as a charge amplifier, and the reliability can be improved.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention includes a sensor element having a vibrating section and a detecting section for detecting an angular velocity, and a driver circuit for supplying a drive signal to the vibrating section of the sensor element. A monitor circuit to which a monitor signal from the sensor element is added.
Driving means for stably driving and vibrating the vibrating portion of the sensor element by applying it to the driver circuit via the GC circuit, charge amplifier to which output from the detecting portion of the sensor element is added, and output of this charge amplifier And a synchronous detector added via a bandpass filter,
A detector that detects the output of the band-pass filter in synchronization with the drive signal from the drive unit and outputs an angular velocity signal, and a synchronous detector that configures the signal synchronized with the drive signal of the drive unit. It is an angular velocity sensor provided with a self-diagnosis means for detecting an abnormality of the sensor element and outputting a self-diagnosis signal by adding it to the preceding stage, and has an effect of providing a self-diagnosis function with a small number of parts.

According to a second aspect of the present invention, the signal synchronized with the drive signal for self-diagnosis is applied to the input terminal of the charge amplifier constituting the detecting means.
The angular velocity sensor described above has an effect of enabling failure detection of the entire sensor.

An invention according to claim 3 is the angular velocity sensor according to claim 1, wherein a signal synchronized with a drive signal for self-diagnosis is applied to an input terminal of a bandpass filter which constitutes the detecting means. Has the effect of increasing the accuracy of failure detection.

The invention according to claim 4 is the angular velocity sensor according to claim 1, wherein a signal synchronized with a drive signal for self-diagnosis is applied to an input terminal of a synchronous detector constituting the detecting means. Has the effect of increasing the accuracy of failure detection.

The invention according to claim 5 is the angular velocity sensor according to any one of claims 2, 3 and 4, wherein the signal synchronized with the drive signal for self-diagnosis is a monitor signal from the sensor element. It has an effect of stabilizing the failure detection.

According to a sixth aspect of the present invention, the self-diagnosis means includes an attenuator for attenuating a signal synchronized with the drive signal, and a circuit preceding the synchronous detector constituting the detecting means for the signal from the attenuator. 1. An injector for injecting into a site.
The angular velocity sensor according to any one of 4), and has an effect of not impairing the original function of the sensor when detecting a failure.

The invention according to claim 7 is the angular velocity sensor according to claim 6, wherein the attenuator is configured so that the amount of attenuation can be varied, and has an effect that the level determination at the time of failure detection can be varied.

The invention according to claim 8 is the angular velocity sensor according to claim 6, wherein the injector is configured to output by varying the phase of the signal synchronized with the drive signal, and the original function of the sensor is maintained. While having a function of detecting a failure.

According to a ninth aspect of the present invention, a sensor element having a vibrating section and a detecting section for detecting an angular velocity, a driver circuit for supplying a drive signal to the vibrating section of the sensor element, and a monitor signal from the sensor element are provided. A monitor circuit to be added, and a driving unit for stably driving and vibrating the vibrating section of the sensor element by applying the output of the monitor circuit to the driver circuit via the AGC circuit; and a detecting section of the sensor element. And a synchronous detector to which the output of this charge amplifier is added via a bandpass filter. The output of the bandpass filter is detected in synchronization with the drive signal from the drive means to detect the angular velocity. A detection unit that outputs a signal and a signal that is synchronized with the drive signal of the drive unit are added before the synchronous detector that constitutes the detection unit. Is an angular velocity sensor equipped with a self-diagnosis means for detecting an abnormality of the sensor element and outputting a self-diagnosis signal, and a switching means for switching the self-diagnosis means to an operating / non-operating state. It has a function of detecting a failure by the diagnostic signal.

According to a tenth aspect of the present invention, the self-diagnosis means is an attenuator for attenuating a signal synchronized with a drive signal, and a signal portion from the attenuator is a circuit portion preceding the synchronous detector constituting the detecting means. 10. The angular velocity sensor according to claim 9, further comprising an injector, wherein the switching means is a switch provided between the attenuator and the injector, which constitutes the self-diagnosis means. It has a function of detecting a failure by a diagnostic signal from the outside without impairing the function.

According to an eleventh aspect of the present invention, the switching means is a switch which responds to an operation from the outside and connects and disconnects a signal synchronized with a drive signal to be injected into a circuit portion in a stage preceding the synchronous detector. The angular velocity sensor according to Item 9, which has an effect of detecting a failure by a diagnostic signal from the outside.

According to a twelfth aspect of the present invention, a sensor element having a vibrating section and a detecting section for detecting an angular velocity, a driver circuit for supplying a drive signal to the vibrating section of the sensor element, and a monitor signal from the sensor element are provided. A monitor circuit to be added, and a driving unit for stably driving and vibrating the vibrating section of the sensor element by applying the output of the monitor circuit to the driver circuit via the AGC circuit; and a detecting section of the sensor element. And a synchronous detector to which the output of this charge amplifier is added via a bandpass filter. The output of the bandpass filter is detected in synchronization with the drive signal from the drive means to detect the angular velocity. A detection unit that outputs a signal and a signal that is synchronized with the drive signal of the drive unit are provided in a stage preceding the synchronous detector that constitutes the detection unit. By detecting the abnormality of the sensor element and outputting a self-diagnosis signal, a self-diagnosis means, a switching means for switching the self-diagnosis means to an operating / non-operating state, and the non-operation of the self-diagnosis The angular velocity sensor is provided with a determination unit that detects the signal level of the detection unit and always determines the abnormality of the sensor element, and has an effect of being able to always detect the abnormality from outside the sensor.

According to a thirteenth aspect of the present invention, the input terminal for the drive signal of the switch is such that the switching logic value of the switch as the switching means is opposite to the logical output of the determiner as the determination means. 13. The angular velocity sensor according to claim 12, wherein the switching means is configured so as not to malfunction due to the logical output of the determiner by electrically coupling the output terminal of the determiner with an output terminal of the determiner. Only the failure can be detected.

According to a fourteenth aspect of the present invention, an input terminal for a drive signal of the switch is provided so that a logical output of the switch as the switching means becomes equal to a logical output of the switch as the switching means. 13. The angular velocity sensor according to claim 12, wherein the output terminal of the judging device is electrically coupled, and the switching means is forcibly operated by the logical output of the judging device to shift to a self-diagnosis mode. It has an effect of keeping the abnormality detection state until a reset signal is applied from the outside.

Hereinafter, embodiments of the present invention will be described. 1 to 6 show a first embodiment of an angular velocity sensor of the present invention. In the figure, reference numeral 1 denotes a resin case having one end opened, and a lid 2 made of resin is attached to the opening to form a sealed space. A circuit board 3 and a weight plate 4 made of metal are housed inside the sealed space. That is, the support pins 5 are planted in contact with the four corners inside the case 1, and the weight plate 4 and the circuit board 3 are elastically supported and fixed by the support pins 5. The weight plate 4 is provided with rubber dampers 6 at four corners for elastically supporting the weight plate 4, and the damper 6 and the circuit board 3 are mounted.
A support leg 7 made of resin is provided between the support pins 5, and the support pin 5 penetrates the damper 6, the support leg 7, and the circuit board 3 from below, and the tip thereof is crushed toward the circuit board 3 side. The circuit board 3 and the weight plate 4 are elastically supported and fixed. Further, as shown in FIG. 3, metal support pins 8 are vertically press-fitted and fixed to the weight board 4 on the circuit board 3 side, and metal support pins 8 are horizontally supported above the support pins 8. One end of the pin 9 is press-fitted and fixed. The diameter of the support pin 9 is as small as about one fifth of the diameter of the support pin 8, and the material is made of a metallic material having a spring property such as a piano wire, and the other end is made of a metal substrate 10. Are fixed by solder.

One end of metal drive plates 11 and 12 is fixed on both sides of the support pin 8 and 9 of the substrate 10, and plate-shaped piezoelectric elements 11a and 12a are fixed to the surfaces thereof. Thereby forming a tuning fork-shaped drive unit.
Further, as shown in FIG. 3, the other ends of the drive plates 11 and 12 are bent in a direction orthogonal to the piezoelectric elements 11a and 12a, and then the detection plates 13 and 14 formed by extension are plate-shaped piezoelectric elements 13a and 13a. 14a is fixed, and the detector is configured by this.

A tuning fork type angular velocity sensor element is formed by the drive section and the detection section. FIG. 1 shows a control circuit for the same angular velocity sensor element. An AC signal of about 1 VP-P, 1.5 KHz is applied from a driver 15 to the piezoelectric element 11a of the drive plate 11. As a result, the drive plates 11 and 12 start tuning fork vibration inward and outward with respect to the support pin 9. Drive plate 1
In the piezoelectric element 12a of No. 2, a voltage proportional to the applied signal is induced by the tuning fork vibration, which passes through the current amplifier 16 and the bandpass filter 17 and outputs the monitor signal shown in FIG. This is then fed back to the driver 15 via the full-wave rectifier 18 and the AGC circuit 19, so that the AGC of the drive signal is kept constant so that the signal amplitude at the point A is always constant.
Control is being performed. In the detection unit, the piezoelectric element 1
Both signals 3a and 14a are combined at point D and input to the charge amplifier 20. Further, the monitor signal synchronized with the tuning fork vibration from the point A is attenuated by the attenuator 32,
It is applied to the non-inverting input terminal of the charge amplifier 20 via the injector 30. The output of the charge amplifier 20 is a bandpass filter 21, a synchronous detector 22, a lowpass filter 23.
Is output from the output terminal 24 via. The signal waveforms at points I, H, E, F, and G according to the signal applied to the charge amplifier 20 from the monitor signal through the attenuator 32 and the injector 30 are E, F, G, and H in FIG. I.

In the present embodiment, the piezoelectric elements 13a and 14a for detecting the angular velocity are bonded to the detection plate 13 via the adhesive 8 as shown in FIG. 4 (a) to detect the angular velocity signal charge. A silver electrode 13b is formed for this purpose.

Here, the detection plate 13, the piezoelectric element 13a and the silver electrode 13b form a parallel plate capacitor as shown in FIG. 4 (b), and an equivalent circuit is as shown in FIG. 4 (c). This time,
The capacitance of the capacitor formed by the piezoelectric element 13a is expressed by the equation (1).

Cs1≈ε · S / d (1) ε: Dielectric constant of piezoelectric body S: Area d: Thickness of piezoelectric body Similarly, the capacitance of the capacitor by the piezoelectric element 14a is expressed by the equation (2). .

Cs2≈ε · S / d (2) ε: Dielectric constant of piezoelectric body S: Area d: Thickness of piezoelectric body Here, the sensitivity of the piezoelectric body for detecting the angular velocity and (1),
The following relationship is established between the capacitors Cs1 and Cs2 expressed by the equation (2).

The sensitivity is proportional to the area S. -Capacitance C is proportional to area S. However, the sensitivity is proportional to the capacitance C.

Therefore, if the change in the capacitance can be detected, the change in the sensitivity can be estimated, and the abnormality in the sensitivity can be detected.

As shown in FIG. 6, the monitor signal A at the point A is attenuated by the attenuator 32 as shown by the waveform I in FIG. 6 and added to the injector 30. The injector 30 is composed of, for example, a capacitor and a resistor as shown in FIG.
Is applied to the non-inverting input terminal of the charge amplifier 20 with a phase shift with respect to the monitor signal A as shown by the waveform H of FIG.
Here, since the inverting input and the non-inverting input of the charge amplifier 20 are virtually the same potential, the signal from the injector 30 applied to the non-inverting input terminal is inverted by the charge amplifier 20 as shown by the waveform D in FIG. It also appears on the input terminal.

As a result, the displacement current ID shown by the waveform D in FIG. 6 is generated in the capacitance components Cs1 and Cs2 of the piezoelectric elements 13a and 14a connected to the inverting input terminals, and as a result, the displacement current ID shown in FIG. A voltage having a waveform E of 6 is output. The output voltage ve at the point E at this time is expressed by the following equation (3).

Ve = Vm · α · (1 / C0) · (Cs1 + Cs2) · ID ∠φ (3) ve: Charge amplifier output voltage E (VP-P) Vm: Monitor voltage (VP-P) α : Attenuation rate of attenuator 32 (0 <α <1) ∠φ: Phase shift due to injector (0 <φ <90 °) C0: Feedback capacitance (pF) of charge amplifier 20 ID: Displacement current (pA) The signal Vout obtained from the output terminal 24 is expressed by equation (4).

Vout = A · D · Vm · α · (1 / C0) · (Cs1 + Cs2) · ID · sin φ ... (4) D: Detection constant of synchronous detector 22 A: DC gain of LPF 23 Signal of FIG. Since E is out of phase with the monitor signal A by ∠φ, it is amplified by the BPF 21 and then the synchronous detector 22
The signal component corresponding to the phase shift is extracted and amplified by the LPF 23 to be a DC offset component, which is output from the terminal 24. Normally, the output offset may be adjusted to, for example, 2.5V in consideration of this DC offset.

Here, from the equation (3), the signal E of FIG. 6 indicates that the capacitances Cs1 and Cs2 of the angular velocity detecting piezoelectric elements 13a and 14a are held.
Since, for example, a disconnection or the like occurs at points B to C in FIG. 1, the signal level changes as shown by the waveforms E and F in FIG. 6, resulting in the voltage at the output terminal 24. The level changes. If this level change is judged by a threshold value, for example, an abnormality can be judged as a sensor failure.

Further, since the input signal of the injector 30 is obtained from the monitor signal of the driving circuit and the output signal is added to the input terminal of the charge amplifier 20, as can be seen from the equation (4), the tuning fork and the driving signal are driven. Since the DC offset change of the output terminal 24 appears regardless of where in the circuit or the detection circuit the failure occurs, the failure of the sensor can always be detected.

FIG. 7 shows another embodiment of the angular velocity sensor of the present invention, in which the signal from the attenuator 32 can be opened / closed by the switch 31 from the outside to the injector 30. The specific circuit is shown in FIG. 8 and the operation waveform is shown in FIG.

Since the monitor signal I attenuated by the attenuator 32 is normally cut by the switch 31, it is not transmitted to the injector 30, so that the sensor output also remains normal. When a signal from the outside, such as a check signal from a computer, is applied to the terminal 33 as indicated by J in FIG. 9, the switch 31 is closed and the signal I from the attenuator 32 is transmitted to the injector 30. As a result, the waveform of each part is H, D, E, F in FIG.
As a result, the output terminal 24 causes an offset fluctuation associated with the check signal applied to the terminal 33 as shown by G in FIG. This offset fluctuation is from (4) above.
Since it is determined by the equation, it is possible to know the abnormal state of the sensor by monitoring this variation.

FIG. 10 shows still another embodiment of the angular velocity sensor of the present invention. A concrete circuit is shown in FIG. 11 and an operation waveform is shown in FIG. In this example, the input terminal from the outside of the switch 31 is shared with the output terminal of the other judging device 28.
The determiner 28 monitors, for example, the output E of the charge amplifier 20 to detect an abnormal voltage generated by, for example, an abnormal shock or vibration applied to the tuning fork from the outside, and outputs the abnormality from the terminal 29 to the outside. Here, the input of the switch 31 is shared with the terminal 29, but the switch 31 is set so that the logic value of the switch 31 is opposite to the logic output of the determiner 28. Therefore, when the switch 31 is not normally operated, an abnormal voltage generated by an abnormal external impact or vibration applied to the tuning fork is detected and the abnormality is notified to the outside. On the other hand, at the time of checking the sensor, a check signal is input from the terminal 29 and the sensor output of the terminal 24 is monitored, so that multi-function failure diagnosis can be performed by one terminal and high cost performance is realized.

Further, when the switching logic value of the switch 31 is set to be equal to the logical output of the judging device 28, the switching device 31 is forcibly forced by the logical output of the judging device 28. It can be operated to shift to the self-diagnosis mode, and the output of the signal as the abnormality detection state can be continuously maintained at the terminal 29 until the external self-diagnosis reset signal is applied.

Here, an actual example for knowing the operating state of the sensor by using the monitor signal has been described, but the offset of the sensor output can be adjusted by the same circuit configuration.
At this time, the attenuation amount may be adjusted by the attenuator 32 or the phase shift amount may be adjusted by the injector 30 to perform a desired offset adjustment. If the attenuation amount and the phase shift are changed by the temperature using the temperature sensitive element, the temperature of the sensor output can be corrected.

The same applies when the output of the injector 30 is added to the bandpass filter 21 and the synchronous detector 22.

[0042]

As described above, the present invention can realize the sensor self-diagnosis mode with a simple structure by applying the signal synchronized with the drive signal of the drive circuit to the circuit preceding the synchronous detector. A highly reliable angular velocity sensor can be realized.

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing an embodiment of an angular velocity sensor of the present invention.

FIG. 2 is an assembled perspective view of a main part of the sensor.

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

FIG. 4A is an enlarged perspective view of a notch of a main part of the sensor, FIG. 4B is a sectional view thereof, and FIG. 4C is an equivalent circuit diagram of the sensor.

FIG. 5 is a circuit diagram showing a circuit configuration of a main part of the sensor.

FIG. 6 is an operation waveform diagram of each part of the sensor.

FIG. 7 is a circuit block diagram showing another embodiment of the angular velocity sensor of the invention.

FIG. 8 is a circuit diagram showing a circuit configuration of a main part of the sensor.

FIG. 9 is an operation waveform diagram of each part of the sensor.

FIG. 10 is a circuit block diagram showing still another embodiment of the angular velocity sensor of the present invention.

FIG. 11 is a circuit diagram showing a circuit configuration of a main part of the sensor.

FIG. 12 is an operation waveform diagram of each part of the sensor.

[Explanation of symbols]

 11, 12 Drive plate 11a, 12a, 13a, 14a Piezoelectric element 13, 14 Detection plate 15 Driver circuit 16 Current amplifier 17, 21 Band pass filter 18 Full wave rectifier 19 AGC circuit 20 Charge amplifier 22 Synchronous detector 23 Low pass filter 30 Injection Device 31 Switch 32 Attenuator

Claims (14)

[Claims] 1. A sensor element having a vibrating section and a detecting section for detecting an angular velocity, a driver circuit for supplying a drive signal to the vibrating section of the sensor element, and a monitor circuit to which a monitor signal from the sensor element is added. A driving means for stably driving and vibrating the vibrating portion of the sensor element by applying the output of the monitor circuit to the driver circuit via the AGC circuit, and the charge to which the output from the detecting portion of the sensor element is added. A detection unit that includes an amplifier and a synchronous detector to which the output of the charge amplifier is added via a bandpass filter, and detects the output of the bandpass filter in synchronization with the drive signal from the drive unit to output an angular velocity signal. And a signal synchronized with the drive signal of the drive means is added to the stage before the synchronous detector constituting the detection means. An angular velocity sensor including a self-diagnosis unit that detects an abnormality in a device and outputs a self-diagnosis signal. 2. The angular velocity sensor according to claim 1, wherein a signal synchronized with a drive signal for self-diagnosis is applied to an input terminal of a charge amplifier which constitutes the detecting means. 3. The angular velocity sensor according to claim 1, wherein a signal synchronized with a drive signal for self-diagnosis is applied to an input terminal of a bandpass filter which constitutes the detecting means. 4. The angular velocity sensor according to claim 1, wherein a signal synchronized with a drive signal for self-diagnosis is applied to an input terminal of a synchronous detector which constitutes the detecting means. 5. The signal synchronized with the drive signal for self-diagnosis is a monitor signal from the sensor element.
The angular velocity sensor according to any one of 3 and 4. 6. The self-diagnosis means includes an attenuator for attenuating a signal synchronized with a drive signal, and an injector for injecting a signal from the attenuator into a circuit portion in a stage preceding the synchronous detector constituting the detecting means. The angular velocity sensor according to any one of claims 1 to 4, which comprises. 7. The angular velocity sensor according to claim 6, wherein the attenuator is configured so that the amount of attenuation can be changed. 8. The angular velocity sensor according to claim 6, wherein the injector is configured to output by varying a phase of a signal synchronized with the drive signal. 9. A sensor element having a vibrating section and a detecting section for detecting an angular velocity, a driver circuit for supplying a drive signal to the vibrating section of the sensor element, and a monitor circuit to which a monitor signal from the sensor element is added. A driving means for stably driving and vibrating the vibrating portion of the sensor element by applying the output of the monitor circuit to the driver circuit via the AGC circuit, and the charge to which the output from the detecting portion of the sensor element is added. A detection unit that includes an amplifier and a synchronous detector to which the output of the charge amplifier is added via a bandpass filter, and detects the output of the bandpass filter in synchronization with the drive signal from the drive unit to output an angular velocity signal. And a signal synchronized with the drive signal of the drive means is added to the stage before the synchronous detector constituting the detection means. A self-diagnosis unit that detects an abnormality in the device and outputs a self-diagnosis signal;
An angular velocity sensor, comprising: a switching unit that switches to a non-operating state. 10. The self-diagnosis means includes an attenuator for attenuating a signal synchronized with a drive signal, and an injector for injecting a signal from the attenuator into a circuit portion preceding the synchronous detector constituting the detection means. 10. The angular velocity sensor according to claim 9, wherein the switching means is a switch provided between the attenuator and the injector that constitute the self-diagnosis means. 11. The switch means is a switch which responds to an operation from the outside to switch a signal synchronized with a drive signal to be injected into a circuit part in a stage preceding the synchronous detector.
The described angular velocity sensor. 12. A sensor element having a vibrating section and a detecting section for detecting an angular velocity, a driver circuit for supplying a drive signal to the vibrating section of the sensor element, and a monitor circuit to which a monitor signal from the sensor element is added. A driving means for stably driving and vibrating the vibrating portion of the sensor element by applying the output of the monitor circuit to the driver circuit via the AGC circuit, and the charge to which the output from the detecting portion of the sensor element is added. A detection unit that includes an amplifier and a synchronous detector to which the output of the charge amplifier is added via a bandpass filter, and detects the output of the bandpass filter in synchronization with the drive signal from the drive unit to output an angular velocity signal. And a signal synchronized with the drive signal of the drive means is added to the stage before the synchronous detector constituting the detection means. Self-diagnosis means for detecting an abnormality of the sensor element and outputting a self-diagnosis signal, switching means for switching the self-diagnosis means to an operating / non-operation state, and a signal of the detection means during the non-operation of the self-diagnosis. An angular velocity sensor including a determination unit that detects a level and always determines abnormality of the sensor element. 13. An input terminal for a drive signal of the switch and an output of the determiner so that the switching logic value of the switch as the switching means is opposite to the logical output of the determiner as the determining means. 13. The angular velocity sensor according to claim 12, wherein the terminal is electrically coupled to the terminal, and the switching unit does not malfunction due to a logical output of the determination unit. 14. The input terminal of the drive signal of the switch and the output terminal of the determiner so that the switching logic value of the switch as the switching means becomes equal to the logical output of the determiner as the determination means. 13. The angular velocity sensor according to claim 12, wherein the switching means is forcibly activated by the logic output of the judging device to shift to the self-diagnosis mode.