JP2010043962A - Circuit and device for detecting angular velocity and method for diagnosing fault of the device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit and device for detecting angular velocity and a method for diagnosing the device for detecting angular velocity, which enhance the accuracy in fault diagnosis without affecting the accuracy in detection of angular velocity. <P>SOLUTION: The circuit 80 for detecting angular velocity includes a drive circuit 20 which supplies a drive signal to a drive electrode 102 of a vibrator 10, and a detecting circuit 30 which forms an angular velocity detection signal 32 according to the angular velocity, based on signals generated in detecting electrodes 112 and 114 of the vibrator 10. In a fault diagnosis mode, the drive circuit 20 forms an angular velocity false signal and supplies the formed angular velocity false signal to the drive electrode 102 of the vibrator 10, superposing it on the drive signal. In the fault diagnosis mode, the detecting circuit 30 forms the angular velocity detection signal 32, based on a signal propagated by the angular velocity false signal to the detecting electrodes 112 and 114 through the capacitive coupling capacity between the drive electrode 102 of the vibrator 10 and the detecting electrodes 112 and 114 thereof. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an angular velocity detection circuit, an angular velocity detection device, and a failure diagnosis method for the angular velocity detection device.

An angular velocity detection device that detects an angular velocity using Coriolis force acting on a vibrator, that is, a vibration gyro is widely used. In recent years, in such an angle detection device, a vibration gyro capable of self-diagnosis of abnormality of the vibrator and its peripheral circuits has been proposed. The vibration gyro described in Patent Document 1 generates a pseudo signal synchronized with a signal output according to an angular velocity, and applies the pseudo signal to at least one of a plurality of detection electrodes of the vibrator, thereby performing synchronous detection. Based on the signal, the abnormality of the detection electrode of the vibrator and the abnormality of the angular velocity detection means connected to the detection electrode can be self-diagnosed.
Japanese Patent Laid-Open No. 2002-213961

  However, in the vibration gyro described in Patent Document 1, since the pseudo signal is applied to the detection electrode of the vibrator, the abnormality of the driving electrode of the vibrator and the abnormality of the vibrator driving means connected to the driving electrode are sufficiently prevented. Cannot self-diagnose. Further, in order not to reduce the detection accuracy of the angular velocity, it is necessary to prevent the impedance of each detection electrode from being unbalanced. However, in the vibration gyro described in Patent Document 1, the output of the pseudo signal generation circuit switches the switch. Therefore, adjustment for equalizing the impedance of each detection electrode is difficult.

  The present invention has been made in view of the above problems, and the failure of the angular velocity detection circuit, the angular velocity detection device, and the angular velocity detection device that can improve the failure diagnosis accuracy without affecting the detection accuracy of the angular velocity. An object is to provide a diagnostic method.

(1) The present invention
An angular velocity detection circuit that is connected to a vibrator that vibrates based on a drive signal and detects an angular velocity,
A vibrator drive unit for supplying the drive signal to the drive electrode of the vibrator;
An angular velocity detection unit that generates an angular velocity detection signal corresponding to the angular velocity based on a signal generated in the detection electrode of the vibrator, and
The vibrator driving unit includes:
At the time of failure diagnosis mode, an angular velocity pseudo signal is generated, and the generated angular velocity pseudo signal is superimposed on the drive signal and supplied to the drive electrode of the vibrator,
The angular velocity detector
In the failure diagnosis mode, the angular velocity detection signal is generated based on a signal that the angular velocity pseudo signal has propagated to the detection electrode via an electrostatic coupling capacitance between the drive electrode and the detection electrode of the vibrator. It is characterized by doing.

  The angular velocity pseudo signal may be any signal that can cause the angular velocity detection unit to generate an angular velocity detection signal similar to the angular velocity detection signal generated when a predetermined angular velocity is applied without applying the angular velocity to the vibrator. In other words, even when the angular velocity detection circuit is stationary (not rotating), by applying an angular velocity pseudo signal to the drive electrode of the vibrator, the angular velocity detection is as if a predetermined angular velocity has been applied to the angular velocity detection circuit. A signal is generated.

  For example, the vibrator driving unit can generate an angular velocity pseudo signal synchronized with the driving signal.

  The angular velocity detection unit can generate the angular velocity detection signal by synchronous detection based on the drive signal, for example.

  The angular velocity detection circuit can be configured to be able to set the failure diagnosis mode at an arbitrary timing by external control.

  According to the present invention, since the angular velocity detection signal is generated based on the signal that the angular velocity pseudo signal applied to the drive electrode of the vibrator propagates to the detection electrode of the vibrator, the failure of the detection electrode of the vibrator or the detection electrode In addition to detecting a failure in the angular velocity detection unit connected to the, a failure in the drive electrode of the vibrator and a failure in the vibrator drive unit connected to the drive electrode can also be detected.

  Further, according to the present invention, since the angular velocity pseudo signal propagates to the detection electrode via the electrostatic coupling capacitance between the drive electrode and the detection electrode of the vibrator, the pseudo signal is directly applied to the detection electrode of the vibrator. There is no need to do. Therefore, it is not necessary to add a wiring connection for failure detection to the detection electrode of the vibrator, so it is easy to equalize the impedance of each detection electrode of the vibrator, and failure detection is performed without reducing the accuracy of angular velocity detection. It can be performed.

(2) The angular velocity detection circuit of the present invention is
A failure diagnosis unit that diagnoses whether at least a part of the vibrator, the vibrator driving unit, and the angular velocity detection unit is failed based on the angular velocity detection signal in the failure diagnosis mode may be included. .

  According to the present invention, since the angular velocity detection circuit can self-diagnose its own failure, the external device does not need to perform failure diagnosis of the angular velocity detection circuit based on the angular velocity detection signal. Therefore, it is possible to reduce the load of fault diagnosis by the external device connected to the angular velocity detection circuit according to the present invention.

(3) In the angular velocity detection circuit of the present invention,
The angular velocity pseudo signal may be a signal having a frequency 2n + 1 times (n is an integer of 1 or more) the frequency of the drive signal.

  According to the present invention, the drive signal and the angular velocity pseudo signal are supplied to the drive electrode of the vibrator, and the frequency of the angular velocity pseudo signal is 2n + 1 times (odd times) the frequency of the drive signal, which adversely affects the drive vibration. Instead, a predetermined DC component can be detected by synchronously detecting the angular velocity pseudo signal with the drive signal. Therefore, according to the present invention, the accuracy of failure diagnosis can be improved without affecting the detection accuracy of angular velocity.

(4) In the angular velocity detection circuit of the present invention,
The angular velocity pseudo signal may be a signal having a frequency 1 / (2n + 1) times (n is an integer of 1 or more) times the frequency of the drive signal.

  According to the present invention, the drive signal and the angular velocity pseudo signal are supplied to the drive electrode of the vibrator, and the frequency of the angular velocity pseudo signal is 1 / (2n + 1) (1 / odd) of the frequency of the drive signal. A predetermined DC component can be detected by synchronously detecting the angular velocity pseudo signal with the drive signal without adversely affecting the signal. Therefore, according to the present invention, the accuracy of failure diagnosis can be improved without affecting the detection accuracy of angular velocity.

(5) The angular velocity detection circuit of the present invention is
Including a non-volatile storage for storing the setting value;
The vibrator driving unit includes:
You may make it produce | generate the said angular velocity pseudo signal which has an amplitude according to the said setting value memorize | stored in the said memory | storage part.

  According to the present invention, since the amplitude of the angular velocity pseudo signal can be changed according to the set value, even if there is a variation in characteristics among the plurality of angular velocity detection circuits, the set value is set for each individual angular velocity detection circuit. By adjusting, the difference in the voltage level of the angular velocity detection signal between the angular velocity detection circuits can be reduced.

  Further, according to the present invention, various angular velocities can be detected in a pseudo manner by changing the set value, so that a more flexible failure diagnosis can be performed according to a user request.

  According to the present invention, the set value of the amplitude of the angular velocity pseudo signal is stored in the nonvolatile storage unit. Therefore, if the set values individually adjusted in accordance with the characteristic variation among the plurality of angular velocity detection devices are stored in the nonvolatile storage unit, the user can easily do without being aware of the characteristics of each angular velocity detection device. Fault diagnosis can be performed.

(6) The present invention
An angular velocity detection device comprising: a vibrator that vibrates based on a drive signal; and an angular velocity detection circuit that is connected to the vibrator and detects an angular velocity,
The vibrator is
A first detection electrode and a second detection electrode, the first electrostatic coupling capacitance between the drive electrode and the first detection electrode, and between the drive electrode and the second detection electrode The drive electrode, the first detection electrode, and the second detection electrode are formed so that the second electrostatic coupling capacitance of the second electrostatic coupling capacitance is different,
The angular velocity detection circuit is
An angular velocity in accordance with an angular velocity based on a signal generated at the first detection electrode and the second detection electrode of the vibrator, and a vibrator driving unit that supplies the drive signal to the drive electrode of the vibrator An angular velocity detection unit that generates a detection signal, and the transducer driving unit generates an angular velocity pseudo signal in the failure diagnosis mode, and superimposes the generated angular velocity pseudo signal on the drive signal to the transducer The angular velocity detection unit, in the failure diagnosis mode, the angular velocity pseudo signal propagates to the first detection electrode via the first electrostatic coupling capacitance; and The angular velocity detection signal is generated based on an amplitude difference between signals transmitted to the second detection electrode through the second electrostatic coupling capacitance.

(7) The present invention
A vibrator that vibrates based on a drive signal, a vibrator drive unit that supplies the drive signal to the drive electrode of the vibrator, and an angular velocity detection signal that corresponds to an angular velocity based on a signal that is generated at the detection electrode of the vibrator An angular velocity detection unit that generates a fault diagnosis method for an angular velocity detection device, comprising:
Generating an angular velocity pseudo signal and superimposing the generated angular velocity pseudo signal on the drive signal to supply to the drive electrode of the vibrator;
The angular velocity detection unit generates the angular velocity detection signal based on a signal in which the angular velocity pseudo signal propagates to the detection electrode via an electrostatic coupling capacitance between the drive electrode and the detection electrode of the vibrator. When,
And diagnosing whether or not at least a part of the vibrator, the vibrator driving unit, and the angular velocity detection unit is out of order based on the angular velocity detection signal.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. Also, not all of the configurations described below are essential constituent requirements of the present invention.

1. Angular Velocity Detection Device FIG. 1 is an example of a functional block diagram of an angular velocity detection device of the present embodiment. The angular velocity detection device 1 includes an angular velocity detection circuit 80 including a drive circuit 20 and a detection circuit 30 and a vibrator 10.

2. The vibrator 10 is a piezoelectric vibrator formed of a thin plate of a piezoelectric material such as quartz, and includes a drive vibration unit 105 and a detection vibration unit 115. The vibrator 10 is excited and oscillated based on the drive signals input from the drive electrodes 102 and 104. When the angular velocity is applied in the excited vibration state, Coriolis force is obtained. The vibrator 10 outputs a detection signal including an angular velocity component based on Coriolis force and a driving vibration component based on excitation vibration. Here, the angular velocity component and the drive vibration component are 90 ° out of phase.

  The vibrator 10 can be realized as, for example, a piezoelectric vibrator having a structure as shown in FIGS. 2 and 3A to 3C.

  As shown in FIGS. 2 and 3A to 3C, the two support portions 130 protrude from the base portion 120 located at the center of the vibrator 10, and the two driving vibration pieces 100 support the respective portions. Connected to the unit 130. Here, the drive vibrating piece 100 is formed so that the longitudinal direction thereof is orthogonal to the longitudinal direction of the support portion 130. Also, two detection vibrating pieces 110 are formed so as to protrude from the base 120. Here, the detection vibrating piece 110 is formed so that its longitudinal direction is parallel to the longitudinal direction of the driving vibrating piece 100.

  Drive electrodes 102 and 104 are provided in the drive vibration unit 105 of the two drive vibrating pieces 100, and the drive electrodes 102 and 104 are connected to the drive circuit 20 (see FIG. 1). In addition, detection electrodes 112 and 114 and a common electrode 116 are provided in the detection vibration portions 115 of the two detection vibrating pieces 110, respectively. The detection electrodes 112 and 114 are connected to the detection circuit 30, and the common electrode 116 is grounded. (See FIG. 1).

  When an AC drive signal is supplied to the drive electrode 102, the two drive vibrating pieces 100 are repeatedly bent in the A direction and the A 'direction by the inverse piezoelectric effect. Here, when the oscillation circuit is configured by a feedback circuit including the drive circuit 20 and the vibrator 10, the frequency of the drive signal is stabilized at the resonance frequency of the drive vibrating piece 100. This is because the drive vibrating piece 100 has a high Q value. When the vibrator 10 is driven by the output of an independent oscillation circuit, the vibrator 10 is forcibly excited at the oscillation frequency of the oscillation circuit. When the vibrator 10 (angular velocity detection device 1) is not rotating, the two driving vibration pieces 100 of the vibrator 10 vibrate symmetrically with respect to the detection vibration piece 110. Does not vibrate. Therefore, electric charges due to the piezoelectric effect generated in the detection electrodes 112 and 114 due to the drive vibration can be suppressed.

  On the other hand, when the vibrator 10 (angular velocity detection device 1) is rotated around the Z axis while the two drive vibrating pieces 100 are repeatedly bending-vibrated in the A direction and the A ′ direction, the two drive pieces Since the Coriolis forces in the B direction and the B ′ direction work alternately on the vibrating piece 100, the two driving vibrating pieces 100 bend and vibrate in the B direction and the B ′ direction. At this time, the two vibrating pieces for detection 110 bend and vibrate in the C direction and the C ′ direction in order to maintain balance. As a result, alternating currents of opposite phases having a magnitude proportional to the angular velocity are generated on the detection electrodes 112 and 114 due to the piezoelectric effect.

Note that an alternating current having the same frequency as the signal supplied to the drive electrode 102 is generated in the detection electrodes 112 and 114 via the electrostatic coupling capacitances C ₁ and C ₂ between the drive electrode 102 and the detection electrodes 112 and 114. To do. Therefore, when the drive vibrating piece 100 is vibrating, an alternating current having the same drive signal frequency as that of the drive vibrating piece 100 is generated in the detection electrodes 112 and 114. As will be described later, this alternating current is used as an angular velocity. There is no false detection.

3. Angular Velocity Detection Circuit An angular velocity detection circuit 80 shown in FIG. 1 includes a drive circuit 20. The drive circuit 20 functions as a vibrator drive unit and supplies a drive signal to the drive electrode 102 of the vibrator 10. The drive circuit 20 can be configured to include, for example, a current-voltage converter (I / V converter) 200, an AC amplifier / comparator 210, an addition circuit 220, and a pseudo signal generation circuit 230.

The input terminal of the current-voltage converter (I / V converter) 200 is connected to the drive electrode 104 of the vibrator 10, and the vibration piece 100 for driving vibrates to cause the vibration of the vibrator 10 based on the piezoelectric effect. The alternating current generated in the drive electrode 104 is converted into an alternating voltage signal centered on the reference voltage _Vref .

The AC amplifier / comparator 210 has an input terminal connected to the output terminal of the current / voltage converter (I / V converter) 200, and an AC voltage signal output from the current / voltage converter (I / V converter) 200. And the output level is switched according to the comparison result between the amplified AC voltage signal and the reference voltage V _ref , and a square wave voltage signal centered on the reference voltage V _ref is output.

  The addition circuit 220 has two input terminals connected to the output terminal of the AC amplifier / comparator 210 and the output terminal of the pseudo signal generation circuit 230, respectively, and the output terminal connected to the drive electrode 102 of the vibrator 10. Yes. The addition circuit 220 adds the output signal (drive signal) of the AC amplifier / comparator 210 and the output signal (angular velocity pseudo signal) of the pseudo signal generation circuit 230 and supplies the added signal to the drive electrode 102 of the vibrator 10. To do.

  The pseudo signal generation circuit 230 has its input terminals connected to the output terminal of the AC amplifier / comparator 210, the output terminal of the storage circuit 50, and the output terminal of the failure diagnosis control circuit 60, respectively.

  The failure diagnosis control circuit 60 sets the operation mode of the angular velocity detection circuit 80 to the failure diagnosis mode based on a signal input from the outside via the external input terminal 70.

When the operation mode of the angular velocity detection circuit 80 is an angular velocity detection mode (a mode in which an angular velocity based on Coriolis force is detected), the output of the pseudo signal generation circuit 230 is controlled to become the reference voltage V _ref . Therefore, the output signal of the AC amplifier / comparator 210 is output to the output terminal of the adder circuit 220 as it is. That is, in the angular velocity detection mode, the drive circuit 20 supplies the output signal of the AC amplifier / comparator 210 to the drive electrode 102 of the vibrator 10 as a drive signal for driving the vibrator 10 (drive vibrating piece 100), and vibrates. The child 10 is excited.

  On the other hand, when the operation mode of the angular velocity detection circuit 80 is set to the failure diagnosis mode, the pseudo signal generation circuit 230 generates an angular velocity pseudo signal based on the output signal of the AC amplifier / comparator 210. Accordingly, a signal obtained by superimposing the angular velocity pseudo signal generated by the pseudo signal generation circuit 230 on the output signal of the AC amplifier / comparator 210 is output to the output terminal of the adder circuit 220. Accordingly, in the failure diagnosis mode, the drive circuit 20 supplies a signal in which the angular velocity pseudo signal is superimposed on the output signal (drive signal) of the AC amplifier / comparator 210 to the drive electrode 102 of the vibrator 10.

  Here, the pseudo signal generation circuit 230 is, for example, a 2n + 1 multiplication circuit (n is 1 or more) that generates an angular velocity pseudo signal having a frequency of 3 times, 5 times, 7 times,... Integer). The 2n + 1 multiplication circuit can be realized by using, for example, a known PLL (Phase Locked Loop) circuit. Further, the pseudo signal generation circuit 230 is, for example, a 2n + 1 frequency dividing circuit that generates an angular velocity pseudo signal having a frequency of 1/3 times, 1/5 times, 1/7 times,... (N is an integer of 1 or more).

  The pseudo signal generation circuit 230 can generate an angular velocity pseudo signal having an amplitude corresponding to the control signal (set value) output from the failure diagnosis control circuit 60. When the angular velocity detection circuit 80 includes a storage circuit 50 such as an EEPROM functioning as a nonvolatile storage unit, the pseudo signal generation circuit 230 has an angular velocity pseudo signal having an amplitude corresponding to the set value stored in the storage circuit 50. Can also be generated.

  The angular velocity detection circuit 80 includes a detection circuit 30. The detection circuit 30 functions as an angular velocity detection unit, and generates an angular velocity detection signal 32 corresponding to the angular velocity based on signals generated at the detection electrodes 112 and 114 of the vibrator 10 by Coriolis force. The detection circuit 30 includes, for example, charge amplifiers 300 and 310, a differential amplifier 320, an AC amplifier 330, a synchronous detection circuit 340, a DC amplifier 350, and an integration circuit (LPF) 360.

The input terminals of the charge amplifiers 300 and 310 are connected to the detection electrodes 112 and 114 of the vibrator 10, respectively, and alternating currents having opposite phases are input. The charge amplifiers 300 and 310 convert the alternating current generated at the detection electrodes 112 and 114 of the vibrator 10 into an alternating voltage signal centered on the reference voltage _Vref , respectively. Here, the phases of the output signals (AC voltage signals) of the charge amplifiers 300 and 310 advance by 90 degrees with respect to the AC current generated in the detection electrodes 112 and 114 of the vibrator 10.

  The differential amplifier 320 has its input terminal connected to the output terminals of the charge amplifiers 300 and 310, and differentially amplifies the output signal of the charge amplifier 300 and the output signal of the charge amplifier 310.

  The AC amplifier 330 has its input terminal connected to the output terminal of the differential amplifier 320 and amplifies the output signal of the differential amplifier 320.

The synchronous detection circuit 340 has its two input terminals connected to the output terminal of the AC amplifier 330 and the output terminal of the AC amplifier / comparator 210, respectively, and based on the output signal (square wave voltage signal) of the AC amplifier / comparator 210. In addition, the angular velocity component is extracted by synchronously detecting the output signal of the AC amplifier 330. For example, when the voltage level of the output signal of the AC amplifier / comparator 210 is higher than the reference voltage V _ref , the synchronous detection circuit 340 outputs the output signal of the AC amplifier 330 as it is and the voltage of the output signal of the AC amplifier / comparator 210. level is lower than the reference voltage V _ref can be configured as a switch circuit that inverts an output signal of the AC amplifier 330 to the reference voltage V _ref.

  The DC amplifier 350 has its input terminal connected to the output terminal of the synchronous detection circuit 340, and amplifies the output signal of the synchronous detection circuit 340.

  The integration circuit (LPF) 360 has an input terminal connected to the output terminal of the DC amplifier 350, attenuates the high frequency component of the output signal of the DC amplifier 350, extracts the DC component, and generates the angular velocity detection signal 32. . The angular velocity detection signal 32 is output to the outside via the external output terminal 74.

  The angular velocity detection circuit 80 can include a failure diagnosis circuit 40 that functions as a failure diagnosis unit. The failure diagnosis circuit 40 has its input terminal connected to the output terminal of the integration circuit (LPF) 360 and vibrates based on the output signal (angular velocity detection signal 32) of the integration circuit (LPF) 360 in the failure diagnosis mode. A diagnosis is made as to whether or not at least a part of the child 10, the drive circuit 20, and the detection circuit 30 is out of order, and the diagnosis result is output to the outside via the external output terminal 72.

  For example, the failure diagnosis circuit 40 can diagnose that the angular velocity detection device 1 has a failure when the angular velocity detection signal 32 exceeds the upper limit reference value or falls below the lower limit reference value in the failure diagnosis mode. Further, the external device (fault diagnosis device) connected to the external output terminal 74 performs fault diagnosis with higher accuracy than the fault diagnosis circuit 40 by acquiring a log of the angular velocity detection signal 32 over a long period of time. Can do.

  The drive circuit 20, the detection circuit 30, the failure diagnosis circuit 40, the storage circuit 50, and the failure diagnosis control circuit 60 can be configured on the same substrate.

  FIG. 4 is a diagram for explaining an example of the operation in the angular velocity detection mode of the angular velocity detection circuit 80 of the present embodiment. The signal waveform shown in FIG. 4 is an example of the signal waveform at points A to H in FIG. 1 when the angular velocity detection device 1 is stationary (not rotating). In FIG. 4, the horizontal axis represents time, and the vertical axis represents voltage.

In the angular velocity detection mode, the drive vibrating piece 100 of the vibrator 10 vibrates at the frequency of the drive signal. Accordingly, a square wave voltage signal (drive signal) having the same frequency as the drive signal is generated at the output (point A) of the AC amplifier / comparator 210. As described above, in the angular velocity detection mode, the voltage at the output (point B) of the pseudo signal generation circuit 230 is equal to the reference voltage V _ref . Therefore, a square wave voltage signal (drive signal) having the same waveform as that of the point A is generated at the output (point C) of the adder circuit 220 and supplied to the drive electrode 102 of the drive vibrating piece 100.

Here, since the vibrator 10 (angular velocity detection device 1) is not rotating, as described above, no charges are generated in the detection electrodes 112 and 114 due to the piezoelectric effect, but between the drive electrode 102 and the detection electrodes 112 and 114. AC currents having the same phase and the same frequency as the drive signal supplied to the drive electrode 102 are generated via the electrostatic coupling capacitors C ₁ and C ₂ .

  This alternating current is converted into an alternating voltage signal by the charge amplifiers 300 and 310. As a result, the output signal of the charge amplifier 300 (point D) and the output of the charge amplifier 310 (point E) include the output signal of the AC amplifier / comparator 210 (point A signal) and the output signal of the adder circuit 220 (point C). A square wave voltage signal whose phase is advanced by 90 degrees with respect to (signal) is generated.

Here, even if the gains of the charge amplifiers 300 and 310 are the same, if the electrostatic coupling capacitances C ₁ and C ₂ are different, the output of the charge amplifier 300 (point D) and the output of the charge amplifier 310 ( The amplitude of the square wave voltage signal generated at point E) is also different. For example, when the electrostatic coupling capacitance C ₁ is larger than the electrostatic coupling capacitance C ₂ , the amplitude of the square wave voltage signal generated at the output (point D) of the charge amplifier 300 is as shown in FIG. It becomes larger than the amplitude of the square wave voltage signal generated at the output (point E).

  The output signal of the charge amplifier 300 (point D signal) and the output signal of the charge amplifier 310 (point E signal) are differentially amplified, and the output of the AC amplifier 330 (point F) is the output signal of the AC amplifier / comparator 210. A square wave voltage signal whose phase is advanced by 90 degrees with respect to (the signal at point A) and the output signal (signal at point C) of the adder circuit 220 is generated.

  The output signal from the AC amplifier 330 (point F signal) is synchronously detected by the synchronous detection circuit 340 based on the output signal from the AC amplifier / comparator 210 (point A signal). As a result, a square wave voltage signal having a ratio of 1: 1 between the high voltage period and the low voltage period is generated at the output (point G) of the synchronous detection circuit 340.

The output signal (point G signal) of the synchronous detection circuit 340 is amplified by the DC amplifier 350, and then the high frequency component is attenuated by the integration circuit (LPF) 360 to extract the DC component. As a result, an angular velocity detection signal 32 having a constant voltage substantially equal to the reference voltage _Vref is generated at the output (point H) of the integration circuit (LPF) 360. Accordingly, the alternating current generated in the detection electrodes 112 and 114 via the electrostatic coupling capacitors C ₁ and C ₂ is not erroneously detected as the angular velocity.

  5 and 6 are diagrams for explaining another example of the operation in the angular velocity detection mode of the angular velocity detection circuit 80 of the present embodiment. The signal waveforms shown in FIGS. 5 and 6 are examples of signal waveforms at points A to H in FIG. 1 when the angular velocity detection device 1 is rotating. Here, FIG. 6 shows a signal waveform when the angular velocity detection device 1 is rotating in the opposite direction to the case of FIG. 5 and 6, the horizontal axis represents time, and the vertical axis represents voltage.

As described with reference to FIG. 4, a square wave voltage signal (drive signal) having the same frequency as the drive signal is generated at the output (point A) of the AC amplifier / comparator 210, and the output (point B) of the pseudo signal generation circuit 230. Is equal to the reference voltage V _ref . Further, a square wave voltage signal (drive signal) having the same waveform as that of the point A is generated at the output (point C) of the adder circuit 220 and supplied to the drive electrode 102 of the drive vibrating piece 100.

  When the angular velocity detection device 1 rotates about the Z axis, an alternating current having the same frequency as the drive signal supplied to the drive electrode 102 is applied to the detection electrodes 112 and 114 due to the piezoelectric effect associated with the bending vibration of the detection vibrating piece 110. appear.

  Here, the alternating current generated in the detection electrode 112 is delayed in phase by 90 degrees with respect to the drive signal supplied to the drive electrode 102. Since the AC current generated in the detection electrode 112 is converted into an AC voltage signal whose phase is advanced by 90 degrees by the charge amplifiers 300 and 310, the output signal (point D) of the charge amplifier 300 is the output signal of the AC amplifier / comparator 210. A sine wave voltage signal having the same phase as the (signal at point A) and the output signal of the adder circuit 220 (signal at point C) is generated.

  On the other hand, since the alternating current generated in the detection electrode 114 is in the opposite phase to the alternating current generated in the detection electrode 112, the output signal (point D signal) of the charge amplifier 300 is output to the output (point E) of the charge amplifier 310. ) Generates a sine wave voltage signal having an opposite phase.

The detection electrodes 112 and 114 generate alternating currents having the same phase and the same frequency as the drive signal supplied to the drive electrode 102 via the electrostatic coupling capacitors C ₁ and C ₂ . As described above, since this alternating current does not affect the detection of the angular velocity, in FIGS. 5 and 6, points D to H when attention is paid only to the alternating current generated in the detection electrodes 112 and 114 based on the Coriolis force. The signal waveform of a point is shown.

  The output signal (point D signal) of the charge amplifier 300 and the output signal (point E signal) of the charge amplifier 310 are differentially amplified, and the output (point F) of the AC amplifier 330 is output to the output (D of the charge amplifier 300). A sine wave voltage signal having the same phase as that of the sine wave voltage signal generated at a point is generated.

  The output signal from the AC amplifier 330 (point F signal) is synchronously detected by the synchronous detection circuit 340 based on the output signal from the AC amplifier / comparator 210 (point A signal). As a result, a signal obtained by full-wave rectifying the output signal (point F signal) of the AC amplifier 330 is generated at the output (point G) of the synchronous detection circuit 340.

The output signal (point G signal) of the synchronous detection circuit 340 is amplified by the DC amplifier 350, and then the high frequency component is attenuated by the integration circuit (LPF) 360 to extract the DC component. As a result, in the case of FIG. 7, the angular velocity detection signal 32 having a voltage higher than the reference voltage _Vref is generated at the output (point H) of the integration circuit (LPF) 360. On the other hand, in the case of FIG. 8, the angular velocity detection signal 32 having a voltage lower than the reference voltage V _ref is generated at the output (point H) of the integration circuit (LPF) 360.

  In this way, the angular velocity detection circuit 80 can detect the angular velocity. Since the voltage level of the angular velocity detection signal 32 is proportional to the magnitude of the Coriolis force (angular velocity magnitude) and its polarity is determined by the rotation direction, the external device connected to the external output terminal 74 can detect the angular velocity detection signal 32. Based on 32, the angular velocity applied to the angular velocity detection device 1 can be calculated.

  7 and 8 are diagrams for explaining an example of the operation in the failure diagnosis mode of the angular velocity detection circuit 80 of the present embodiment. The signal waveforms shown in FIGS. 7 and 8 are shown in FIG. 1 when an angular velocity pseudo signal having a frequency three times the frequency of the drive signal is generated when the angular velocity detection device 1 is stationary (not rotating). It is an example of the signal waveform in A point-H point. Here, FIG. 8 shows a signal waveform when an angular velocity pseudo signal that is 180 degrees out of phase with respect to the angular velocity pseudo signal generated in the case of FIG. 7 is generated. 7 and 8, the horizontal axis represents time, and the vertical axis represents voltage.

  In the failure diagnosis mode, as in the angular velocity detection mode, the drive vibrating piece 100 of the vibrator 10 vibrates at the frequency of the drive signal. Accordingly, a square wave voltage signal (drive signal) having the same frequency as the drive signal is generated at the output (point A) of the AC amplifier / comparator 210. Further, as described above, an angular velocity pseudo signal is generated at the output (point B) of the pseudo signal generation circuit 230 in the failure detection mode.

  Here, assuming that the pseudo signal generation circuit 230 is configured as a triple circuit, as shown in FIGS. 7 and 8, in the failure detection mode, the output (point B) of the pseudo signal generation circuit 230 has an AC amplifier / A square wave voltage signal having a frequency three times the frequency of the output signal of the comparator 210 (the signal at point A) is generated as an angular velocity pseudo signal. Therefore, a signal obtained by adding the square wave voltage signal generated at the output (point A) of the AC amplifier / comparator 210 and the square wave voltage signal having a frequency three times that of the square amplifier is generated at the output (point C) of the adder circuit 220.

The detection electrodes 112 and 114 generate an alternating current having the same phase as the drive signal and the angular velocity pseudo signal supplied to the drive electrode 102 via the electrostatic coupling capacitors C ₁ and C ₂ , and the alternating current is a charge amplifier. It is converted into an AC voltage signal by 300 and 310.

  Here, as described with reference to FIG. 4, even if an alternating current having the same phase and the same frequency as the drive signal supplied to the drive electrode 102 is generated in the detection electrodes 112 and 114, the angular velocity detection is not affected. FIG. 7 shows signal waveforms at points D to H when attention is paid only to the alternating current generated in the detection electrodes 112 and 114 by the angular velocity pseudo signal.

  That is, the output of the charge amplifier 300 (point D) and the output of the charge amplifier 310 (point E) have a 90 degree phase with respect to the angular velocity pseudo signal (the output signal of the pseudo signal generation circuit 230 (the signal at the point B)). An advanced square wave voltage signal is generated.

Here, for example, when the electrostatic coupling capacitance C ₁ is greater than the electrostatic coupling capacitance C _2, as shown in FIGS. 7 and 8, the amplitude charge amplifier of the output signal of the charge amplifier 300 (signal at point D) It becomes larger than the amplitude of the output signal 310 (signal at point E).

  The output signal (point D signal) of the charge amplifier 300 and the output signal (point E signal) of the charge amplifier 310 are differentially amplified, and the output (point F) of the AC amplifier 330 is 90 degrees with respect to the angular velocity pseudo signal. A square wave voltage signal with an advanced phase is generated.

  The output signal from the AC amplifier 330 (point F signal) is synchronously detected by the synchronous detection circuit 340 based on the output signal from the AC amplifier / comparator 210 (point A signal). As a result, a square wave voltage signal in which the high voltage period and the low voltage period do not have a ratio of 1: 1 is generated at the output (point G) of the synchronous detection circuit 340.

  In the case of FIG. 7, a square wave voltage signal having a ratio of 2: 1 between the high voltage period and the low voltage period is generated at the output (point G) of the synchronous detection circuit 340. On the other hand, in the case of FIG. 8, a square wave voltage signal in which the high voltage period and the low voltage period are in a ratio of 1: 2 is generated at the output (point G) of the synchronous detection circuit 340.

The output signal (point G signal) of the synchronous detection circuit 340 is amplified by the DC amplifier 350, and then the high frequency component is attenuated by the integration circuit (LPF) 360 to extract the DC component. As a result, in the case of FIG. 7, the angular velocity detection signal 32 having a voltage higher than the reference voltage V _ref is generated at the output (point H) of the integration circuit (LPF) 360 as in FIG. On the other hand, in the case of FIG. 8, the angular velocity detection signal 32 having a voltage lower than the reference voltage V _ref is generated at the output (point H) of the integration circuit (LPF) 360 as in FIG.

  That is, the angular velocity detection circuit 80 (detection circuit 30) is the same as that of FIGS. 5 and 6 based on the angular velocity pseudo signal having the waveform shown in FIGS. 7 and 8 even when the angular velocity is not applied in the stationary state. The angular velocity in the rotation direction can be detected in a pseudo manner.

Here, the voltage level of the angular velocity detection signal 32 is determined by the frequency and amplitude of the angular velocity pseudo signal, the electrostatic coupling capacitances C ₁ and C ₂ , the characteristics of each circuit, and the like. When there is a failure, the voltage level of the angular velocity detection signal 32 is different from the expected value. Therefore, the failure diagnosis circuit 40 or the external device (failure diagnosis device) connected to the external output terminal 74 can diagnose the failure of the angular velocity detection device 1 based on the angular velocity detection signal 32.

Thus, since the frequency of the angular velocity pseudo signal is three times (odd times) the frequency of the drive signal, the output signal (point H signal) of the integration circuit (LPF) 360 does not adversely affect the drive vibration. A DC component having a voltage higher or lower than the reference voltage V _ref can be detected. Therefore, by generating an angular velocity pseudo signal having a frequency that is three times (odd times) the frequency of the drive signal, the accuracy of failure diagnosis can be improved without affecting the accuracy of angular velocity detection of the angular velocity detection device 1.

The larger the difference between the electrostatic coupling capacitance C ₁ and the electrostatic coupling capacitance C ₂ , the larger the amplitude of the input signal (output signal of the AC amplifier 330) of the synchronous detection circuit 340, and thus the voltage level of the angular velocity detection signal 32. The absolute value of becomes larger, and the accuracy of fault diagnosis can be improved. Therefore, as the difference in the electrostatic coupling capacitance C ₁ and the electrostatic coupling capacitance C ₂ is greater, may be formed a driving electrode 102 and 104 and the detection electrodes 112 and 114 of the vibrator 10. In addition, by providing a difference between the gain amount of the charge amplifier 300 and the gain amount of the charge amplifier 310, the absolute value of the voltage level of the angular velocity detection signal 32 can be increased, so that the accuracy of failure diagnosis can be improved.

  9 and 10 are diagrams for explaining another example of the operation in the failure diagnosis mode of the angular velocity detection circuit 80 of the present embodiment. The signal waveforms shown in FIG. 9 and FIG. 10 are diagrams when an angular velocity pseudo signal having a frequency 1/3 of the frequency of the drive signal is generated when the angular velocity detection device 1 is stationary (not rotating). It is an example of the signal waveform in A point-H point of 1. Here, FIG. 10 shows a signal waveform when an angular velocity pseudo signal that is 180 degrees out of phase with the angular velocity pseudo signal generated in the case of FIG. 9 is generated. 9 and 10, the horizontal axis represents time, and the vertical axis represents voltage.

  As described with reference to FIGS. 7 and 8, a square wave voltage signal (drive signal) having the same frequency as the drive signal is generated at the output (point A) of the AC amplifier / comparator 210, and the output (pseudo signal generation circuit 230) ( An angular velocity pseudo signal is generated at point B).

  Here, if the pseudo signal generation circuit 230 is configured as a divide-by-3 circuit, as shown in FIGS. 9 and 10, in the failure detection mode, the output (point B) of the pseudo signal generation circuit 230 is an AC amplifier. / A square wave voltage signal having a frequency that is 1/3 of the frequency of the output signal of the comparator 210 (signal at point A) is generated as an angular velocity pseudo signal. Accordingly, a signal obtained by adding the square wave voltage signal generated at the output (point A) of the AC amplifier / comparator 210 and the square wave voltage signal having a frequency of 1/3 of the output is generated at the output (point C) of the adder circuit 220. .

Similar to FIGS. 7 and 8, the output (point D) of the charge amplifier 300 and the output (point E) of the charge amplifier 310 are respectively connected to the detection electrodes 112 and 114 via electrostatic coupling capacitors C ₁ and C _2. An alternating voltage signal is generated by converting the generated alternating current. Here, FIGS. 9 and 10 show signal waveforms at points D to H when attention is paid only to the alternating current generated in the detection electrodes 112 and 114 by the angular velocity pseudo signal.

  Similarly to FIGS. 7 and 8, the output signal of the charge amplifier 300 (D point signal) and the charge amplifier 310 output signal (E point signal) are differentially amplified and the AC amplifier 330 output (F point). A square wave voltage signal whose phase is advanced by 90 degrees with respect to the angular velocity pseudo signal is generated, and the output signal (point F signal) of the AC amplifier 330 is output by the synchronous detection circuit 340 to the output signal ( Synchronous detection based on the signal at point A). As a result, a square wave voltage signal in which the high voltage period and the low voltage period do not have a ratio of 1: 1 is generated at the output (point G) of the synchronous detection circuit 340.

  In the case of FIG. 9, a square wave voltage signal in which the high voltage period and the low voltage period are in a ratio of 2: 1 is generated at the output (point G) of the synchronous detection circuit 340. On the other hand, in the case of FIG. 10, a square wave voltage signal in which the high voltage period and the low voltage period are in a ratio of 1: 2 is generated at the output (point G) of the synchronous detection circuit 340.

The output signal (signal at point G) of the synchronous detection circuit 340 is amplified by the DC amplifier 350, and then the high frequency component is attenuated by the integration circuit (LPF) 360 to extract the DC component. In the case of FIG. An angular velocity detection signal 32 having a voltage higher than the reference voltage V _ref is generated at the output (point H) of the integrating circuit (LPF) 360 as in FIG. On the other hand, in the case of FIG. 10, the angular velocity detection signal 32 having a voltage lower than the reference voltage V _ref is generated at the output (point H) of the integration circuit (LPF) 360 as in FIG.

  That is, the angular velocity detection circuit 80 (detection circuit 30) is the same as the case of FIGS. 5 and 6 based on the angular velocity pseudo signal having the waveform shown in FIGS. The angular velocity in the rotation direction can be detected in a pseudo manner.

  Accordingly, as described with reference to FIGS. 7 and 8, the failure diagnosis circuit 40 or the external device (failure diagnosis device) connected to the external output terminal 74 may cause the failure of the angular velocity detection device 1 based on the angular velocity detection signal 32. Can be diagnosed.

Thus, since the frequency of the angular velocity pseudo signal is 1/3 (1 / odd number) of the frequency of the drive signal, the output signal of the integration circuit (LPF) 360 (the signal at the point H) is not adversely affected by the drive vibration. ), A DC component having a voltage higher or lower than the reference voltage V _ref can be detected. Therefore, by generating an angular velocity pseudo signal having a frequency that is 1/3 (1 / odd) of the frequency of the drive signal, it is possible to improve the accuracy of failure diagnosis without affecting the angular velocity detection accuracy of the angular velocity detection device 1. it can.

  As described above with reference to FIGS. 1 to 10, according to the angular velocity detection circuit of this embodiment, the angular velocity pseudo signal applied to the drive electrode 102 of the vibrator 10 propagates to the detection electrodes 112 and 114 of the vibrator 10. Since the angular velocity detection signal 32 is generated based on the signal, not only the failure of the detection electrodes 112 and 114 of the vibrator 10 and the failure of the detection circuit 30 connected to the detection electrodes 112 and 114 can be detected. The failure of the drive electrodes 102 and 104 and the failure of the drive circuit 20 connected to the drive electrodes 102 and 104 can also be detected.

Further, according to the angular velocity detection circuit of the present embodiment, the angular velocity pseudo signal is generated by detecting the detection electrode 112 and the detection electrode 112 via the electrostatic coupling capacitances C ₁ and C ₂ between the drive electrode 102 and the detection electrodes 112 and 114 of the vibrator 10. Therefore, it is not necessary to directly apply a pseudo signal to the detection electrodes 112 and 114 of the vibrator 10. Therefore, since it is not necessary to add a wiring connection for detecting a failure to the detection electrodes 112 and 114 of the vibrator 10, it is easy to equalize the impedances of the detection electrodes 112 and 114 of the vibrator 10, and in the angular velocity detection mode. Failure detection can be performed without reducing the accuracy of angular velocity detection.

  Further, according to the angular velocity detection circuit of the present embodiment, the failure diagnosis circuit 40 can self-diagnose a failure of the angular velocity detection device 1, so that an external device can diagnose the failure of the angular velocity detection device 1 based on the angular velocity detection signal 32. There is no need to do. Therefore, it is possible to reduce the load of failure diagnosis of the external device connected to the angular velocity detection device 1.

  Further, according to the angular velocity detection circuit of the present embodiment, the pseudo signal generation circuit 230 can change the amplitude of the angular velocity pseudo signal according to the set value output from the failure diagnosis control circuit 60. Even if there is a characteristic variation between the two, the difference in voltage level of the angular velocity detection signal 32 between the angular velocity detectors can be reduced by adjusting the set value for each angular velocity detector.

  Further, according to the angular velocity detection circuit of the present embodiment, various angular velocities can be detected in a pseudo manner by changing the setting value of the amplitude of the angular velocity pseudo signal, so that a more flexible failure can be made according to the user's request. Diagnosis can be made.

  Further, according to the angular velocity detection device of the present embodiment, the set value of the amplitude of the angular velocity pseudo signal can be stored in the nonvolatile storage circuit 50. Therefore, if the storage circuit 50 stores the set values individually adjusted according to the characteristic variation among the plurality of angular velocity detection devices, the user can easily break down without being aware of the characteristics of each angular velocity detection device. Diagnosis can be made.

4). FIG. 11 is a diagram illustrating an example of a failure diagnosis system for the angular velocity detection device according to the present embodiment.

  The failure diagnosis system 400 of the present embodiment includes an angular velocity detection device 1 and a failure diagnosis device 2. In addition, since the structure and operation | movement of the angular velocity detection apparatus 1 are as having demonstrated using FIGS. 1-10, the detailed description is abbreviate | omitted.

  The failure diagnosis device 2 sets the operation mode of the angular velocity detection device 1 to the failure diagnosis mode via the external input terminal 70 of the angular velocity detection device. The failure diagnosis device 2 can set the operation mode of the angular velocity detection device 1 to the failure diagnosis mode at an arbitrary timing. For example, the failure diagnosis device 2 may set the operation mode of the angular velocity detection device 1 to the failure diagnosis mode every time an initialization signal is supplied to the failure diagnosis system 400 from the outside.

  Further, the failure diagnosis device 2 provides a set value for controlling the amplitude of the angular velocity pseudo signal generated by the drive circuit 20 (pseudo signal generation circuit 230) of the angular velocity detection device 1 in the failure diagnosis mode via the external input terminal 70. The angular velocity detection device 1 is supplied.

  When the angular velocity detection device 1 is set to the failure diagnosis mode, it generates an angular velocity pseudo signal having an amplitude corresponding to the set value, and outputs the angular velocity detection signal 32 via the external output terminal 74. Based on the detection signal 32, it is diagnosed whether or not the angular velocity detection device 1 has failed.

  The failure diagnosis device 2 can diagnose that the angular velocity detection device 1 has a failure when, for example, the angular velocity detection signal 32 exceeds the upper limit reference value or falls below the lower limit reference value in the failure diagnosis mode. Further, the failure diagnosis apparatus 2 can perform failure diagnosis with higher accuracy by acquiring a log of the angular velocity detection signal 32 over a long period of time.

  Note that the failure diagnosis apparatus 2 can be realized by, for example, a general-purpose microcomputer or dedicated hardware.

5). Fault Diagnosis Method of Angular Velocity Detection Device FIG. 12 is a flowchart for explaining a failure diagnosis method of the angular velocity detection device of the present embodiment.

  In the present embodiment, an angular velocity detection device that is a target of failure diagnosis is generated in a vibrator that vibrates based on a drive signal, a vibrator drive unit that supplies a drive signal to the drive electrode of the vibrator, and a detection electrode of the vibrator. And an angular velocity detection unit that generates an angular velocity detection signal corresponding to the angular velocity based on the signal. For example, the angular velocity detection device 1 that is the target of failure diagnosis may be the angular velocity detection device 1 shown in FIG. However, the angular velocity detection device that is the target of failure diagnosis in this embodiment may not include the failure diagnosis circuit 40, the storage circuit 50, and the failure diagnosis control circuit 60. Furthermore, the angular velocity detection device that is the target of failure diagnosis in this embodiment may not include the adding circuit 220 and the pseudo signal generating circuit 230.

  In the failure diagnosis method for the angular velocity detection device according to the present embodiment, first, an angular velocity pseudo signal is generated, and the angular velocity pseudo signal is supplied to the drive electrode of the vibrator of the angular velocity detection device (step S10).

  Next, angular velocity detection is performed based on the signal that the angular velocity pseudo signal supplied to the drive electrode of the vibrator in step S10 propagates to the detection electrode via the electrostatic coupling capacitance between the drive electrode and the detection electrode of the vibrator. The angular velocity detection unit of the device generates an angular velocity detection signal (step S20).

  Finally, based on the angular velocity detection signal generated in step S20, it is diagnosed whether or not at least a part of the transducer, transducer drive unit, and angular velocity detection unit of the angular velocity detection device has failed (step S30).

  According to the failure diagnosis method of the angular velocity detection device of the present embodiment, the angular velocity detection signal is generated based on the signal transmitted from the angular velocity pseudo signal applied to the drive electrode of the vibrator to the detection electrode of the vibrator. In addition to detecting failure of the detection electrode of the child and failure of the detection circuit connected to the detection electrode, failure of the drive electrode of the vibrator and failure of the drive circuit connected to the drive electrode can also be detected.

  In addition, according to the failure diagnosis method for the angular velocity detection device of the present embodiment, the angular velocity pseudo signal propagates to the detection electrode via the electrostatic coupling capacitance between the drive electrode and the detection electrode of the transducer. There is no need to apply a pseudo signal directly to the electrode. Accordingly, since it is not necessary to add a wiring connection for detecting a failure to the detection electrode of the vibrator, it is easy to make the impedance of the detection electrode of the vibrator equal, and the angular velocity detection accuracy of the angular velocity detection device is reduced. Failure detection can be performed.

  In addition, this invention is not limited to this embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention.

  The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

An example of the functional block diagram of the angular velocity detection apparatus of this embodiment. The figure for demonstrating the vibrator | oscillator contained in the angular velocity detection apparatus of this embodiment. 3A to 3C are a sectional view taken along line VIIA-VIIA, a sectional view taken along line VIIB-VIIB, and a sectional view taken along line VIIC-VIIC of the vibrator shown in FIG. The figure for demonstrating an example of the operation | movement in the angular velocity detection mode of the angular velocity detection circuit of this embodiment. The figure for demonstrating another example of operation | movement in the angular velocity detection mode of the angular velocity detection circuit of this embodiment. The figure for demonstrating another example of operation | movement in the angular velocity detection mode of the angular velocity detection circuit of this embodiment. The figure for demonstrating an example of operation | movement in the failure diagnosis mode of the angular velocity detection circuit of this embodiment. The figure for demonstrating an example of operation | movement in the failure diagnosis mode of the angular velocity detection circuit of this embodiment. The figure for demonstrating another example of operation | movement in the failure diagnosis mode of the angular velocity detection circuit of this embodiment. The figure for demonstrating another example of operation | movement in the failure diagnosis mode of the angular velocity detection circuit of this embodiment. The figure which shows an example of the failure diagnosis system of the angular velocity detection apparatus of this Embodiment. The flowchart for demonstrating the failure diagnosis method of the angular velocity detection apparatus of this Embodiment.

Explanation of symbols

1 angular velocity detection device, 10 vibrator, 20 drive circuit, 30 detection circuit, 32 angular velocity detection signal, 40 failure diagnosis circuit, 50 storage circuit, 60 failure diagnosis control circuit, 70 external input terminal, 72 external output terminal, 74 external output Terminal, 80 Angular velocity detection circuit, 100 Driving vibration piece, 102 Driving electrode, 104 Driving electrode, 105 Driving vibration section, 110 Detection vibrating piece, 112 Detection electrode, 114 Detection electrode, 115 Detection vibration section, 116 Common electrode, 120 Base, 130 Support, 200 Current-voltage converter (I / V converter), 210 AC amplifier / comparator, 220 Adder circuit, 230 Pseudo signal generation circuit, 300 Charge amplifier, 310 Charge amplifier, 320 Differential amplifier, 330 AC Amplifier, 340 Synchronous detection circuit, 350 DC amplifier, 360 Integration circuit (LPF), 400 Fault diagnosis system

Claims (7)

An angular velocity detection circuit that is connected to a vibrator that vibrates based on a drive signal and detects an angular velocity,
A vibrator drive unit for supplying the drive signal to the drive electrode of the vibrator;
An angular velocity detection unit that generates an angular velocity detection signal corresponding to the angular velocity based on a signal generated in the detection electrode of the vibrator, and
The vibrator driving unit includes:
At the time of failure diagnosis mode, an angular velocity pseudo signal is generated, and the generated angular velocity pseudo signal is superimposed on the drive signal and supplied to the drive electrode of the vibrator,
The angular velocity detector
In the failure diagnosis mode, the angular velocity detection signal is generated based on a signal that the angular velocity pseudo signal has propagated to the detection electrode via an electrostatic coupling capacitance between the drive electrode and the detection electrode of the vibrator. An angular velocity detection circuit. In claim 1,
And a failure diagnosis unit that diagnoses whether at least a part of the vibrator, the vibrator driving unit, and the angular velocity detection unit is in failure based on the angular velocity detection signal in the failure diagnosis mode. An angular velocity detection circuit. In claim 1 or 2,
The angular velocity detection circuit according to claim 1, wherein the angular velocity pseudo signal is a signal having a frequency that is 2n + 1 times (n is an integer of 1 or more) the frequency of the drive signal. In claim 1 or 2,
The angular velocity detection circuit according to claim 1, wherein the angular velocity pseudo signal is a signal having a frequency that is 1 / (2n + 1) times (n is an integer of 1 or more) the frequency of the drive signal. In any one of Claims 1 thru | or 4,
Including a non-volatile storage for storing the setting value;
The vibrator driving unit includes:
An angular velocity detection circuit that generates the pseudo angular velocity signal having an amplitude corresponding to the set value stored in the storage unit. An angular velocity detection device comprising: a vibrator that vibrates based on a drive signal; and an angular velocity detection circuit that is connected to the vibrator and detects an angular velocity,
The vibrator is
A first detection electrode and a second detection electrode, the first electrostatic coupling capacitance between the drive electrode and the first detection electrode, and between the drive electrode and the second detection electrode The drive electrode, the first detection electrode, and the second detection electrode are formed so that the second electrostatic coupling capacitance of the second electrostatic coupling capacitance is different,
The angular velocity detection circuit is
An angular velocity in accordance with an angular velocity based on a signal generated at the first detection electrode and the second detection electrode of the vibrator, and a vibrator driving unit that supplies the drive signal to the drive electrode of the vibrator An angular velocity detection unit that generates a detection signal, and the transducer driving unit generates an angular velocity pseudo signal in the failure diagnosis mode, and superimposes the generated angular velocity pseudo signal on the drive signal to the transducer The angular velocity detection unit, in the failure diagnosis mode, the angular velocity pseudo signal propagates to the first detection electrode via the first electrostatic coupling capacitance; and An angular velocity detection device that generates the angular velocity detection signal based on an amplitude difference between signals transmitted from the pseudo pseudo angular velocity signal to the second detection electrode via the second electrostatic coupling capacitance. A vibrator that vibrates based on a drive signal, a vibrator drive unit that supplies the drive signal to the drive electrode of the vibrator, and an angular velocity detection signal that corresponds to an angular velocity based on a signal that is generated at the detection electrode of the vibrator An angular velocity detection unit that generates a fault diagnosis method for an angular velocity detection device, comprising:
Generating an angular velocity pseudo signal and superimposing the generated angular velocity pseudo signal on the drive signal to supply to the drive electrode of the vibrator;
The angular velocity detection unit generates the angular velocity detection signal based on a signal in which the angular velocity pseudo signal propagates to the detection electrode via an electrostatic coupling capacitance between the drive electrode and the detection electrode of the vibrator. When,
And a step of diagnosing whether at least a part of the vibrator, the vibrator driving unit, and the angular velocity detection unit is out of order based on the angular velocity detection signal. Fault diagnosis method.

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