JPH10267665A - Sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect an angular velocity around a swing axis by swinging one of a plurality of vibrators (weight parts) which is supported in a cantilever manner in the same direction in a first direction and the remainder in an opposite second direction, calculating the spread difference of the swing locus of the vibrators in both direction, and eliminating an acceleration component in the swing axis direction of a scheduled swing surface. SOLUTION: Vibrators 2 and 7 and piezoelectric elements 4a-4d and 9a-9d, magnets 5a-5d and 10a-10d, coils 6a-6d and 11a-11d, a drive circuit 12, and a detection circuit 13 are provided on a substrate 1. The piezoelectric elements 4a and 4b and 4c and 4d output signals according to the inclination of the vibrator 2 in X-axis or Y-axis direction. The vibrators 2 and 7 have nearly the same resonance frequency in the flex direction, and the piezoelectric elements 9a-9d output signals according to the inclination of the vibrator 7 in X-axis and Y-axis directions. The drive circuit 12 allows a current to flow to the coils 6a-6d and 11a-11d at specific frequency and phase. The detection circuit 13 calculates the spread difference of the swing locus of the vibrators 2 and 7 in both directions, and detects an angular velocity around an axis excluding the acceleration constituent in the direction of the swing axis on a scheduled swing surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a sensor for detecting angular velocity and acceleration applied to a device.

[0002]

2. Description of the Related Art Conventionally, an angular velocity sensor for detecting a biaxial angular velocity by rotating a vibrator while fixing one end of the vibrator has been disclosed in Japanese Patent Application Laid-Open No. 7-92175 by the present applicant. I have.

[0003]

The above-described sensor detects an angular velocity about two axes perpendicular to and parallel to a supporting member for supporting the vibrator.

However, recently, research on virtual reality has been advanced, and for example, an application has been announced in which movement of a person is detected by an angular velocity sensor and an acceleration sensor and an image corresponding to the detected motion is displayed. A sensor capable of detecting not only the angular velocity and acceleration around the two axes described above but also the angular velocity and acceleration around an axis perpendicular to the two orthogonal axes (an axis parallel to the longitudinal direction of the vibrator) is provided. Is desired.

(Object of the Invention) A first object of the present invention is to provide a sensor capable of outputting an angular velocity signal about a turning axis of a weight portion with high detection accuracy.

A second object of the present invention is to provide a high detection accuracy,
It is an object of the present invention to provide a sensor capable of outputting an acceleration signal in the direction of the turning axis of the weight.

[0007]

In order to achieve the first object, according to the present invention, a plurality of weights and a plurality of weights are cantilevered in the same direction. A supporting means for supporting, applying a driving force to the supporting means, turning at least one of the plurality of weight portions in a first direction, and rotating a remaining weight portion in a second direction opposite to the first direction. And a difference between the spread of the turning locus of the weight portion turned in the second direction and the spread of the turning locus of the weight portion turned in the second direction. A sensor for calculating the angular velocity around the axis, excluding an acceleration component in a direction of a turning axis of the turning surface on which the driving section is to turn the weight portion.

In order to achieve the second object,
The present invention according to claims 3 to 5, wherein at least one of the plurality of weights, support means for cantilevering the plurality of weights in the same direction, and a driving force applied to the support means, Drive means for turning one in a first direction and turning the remaining weight in a second direction opposite to the first direction, and the drive means for turning in the first direction Calculates the sum of the spread of the turning locus of the weight portion and the spread of the turning locus of the weight portion turning in the second direction, and the driving means angular velocity about the turning axis of the planned turning surface on which the weight portion turns. And a detecting means for detecting the acceleration in the axial direction excluding the component.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a perspective view showing a mechanical configuration of a sensor according to a first embodiment of the present invention. FIGS. 2 and 3 show a case where a vibrator is turned to detect a tilt of the vibrator. FIG. 3 is a block diagram illustrating a configuration of a circuit that detects an angular velocity and an acceleration applied to a sensor.

In a first embodiment of the present invention shown in FIGS. 1 to 3, a vibrator portion (vibration body) of a sensor is constituted by parts using ordinary machining, and is electromagnetically driven by a coil and a magnet. This is an example in which the vibrator is caused to make a revolving motion, and the inclination of the vibrator is detected by a piezoelectric element.

In FIG. 1, 1 is a substrate, 2 is a first vibrator, 3 is a first vibration base, 4a to 4d are piezoelectric elements,
a to 5d (however, 5b is not visible) are magnets, 6a
6d (however, 6b is not visible) is a coil, 7 is a second vibrator, 8 is a second vibration base, 9a to 9d are piezoelectric elements, 10a to 10d (however, 10b is not visible) is a magnet, 11a to 11d (however, 11b is not visible) are coils, 12 is a drive circuit for rotating the vibrator, and 13 is a detection circuit that detects the inclination of the vibrator and detects signals of angular velocity and acceleration. .

The substrate 1 is made of, for example, a ceramic substrate or a glass epoxy substrate. On the substrate 1, a first vibrator 2, a first vibration base 3, piezoelectric elements 4a to 4d,
A first vibrator 400 composed of magnets 5a to 5d and coils 6a to 6d, a second vibrator 7, a second vibration base 8, piezoelectric elements 9a to 9d, and magnets 10a to 1d.
A second vibrating body 410 including 0d and coils 11a to 11d, a driving circuit 12, and a detecting circuit 13 are provided. Further, a power supply terminal and terminals for outputting an angular velocity signal and an acceleration signal are provided on the substrate 1.
Are not shown.

The first vibrator 2 is made by lathing brass, for example, and has one end fixed to the first vibration base 3 by means such as press fitting.

The first vibration base 3 is made of, for example, a phosphor bronze plate, and has a substantially square flat portion to which the magnets 5a to 5d are fixed, and first to first flat portions provided at the centers of the respective sides of the square. It has four legs 3a, 3b, 3c, 3d,
The distal ends of the first to fourth legs 3a, 3b, 3c, 3d are fixed to the substrate 1, respectively.

The first to fourth piezoelectric elements 4a, 4b, 4c,
4 d is made of, for example, PZT (lead zirconate titanate), has a substantially rectangular shape, is polarized in the thickness direction, and is attached to the first to fourth legs 3 a to 3 d of the first vibration base 3. Each is fixed by bonding.

First to fourth magnets 5a, 5b, 5
c and 5d are made of, for example, a ferrite plastic magnet, and are magnetized in the thickness direction.
For example, the surface of the first magnet 5a on the substrate 1 side is an N-pole and the second magnet 5b (not shown in FIG. The surface of the substrate 1 on the side of the substrate 1 has an S pole, and the substrate 1 of the third magnet 5c.
The surface of the fourth magnet 5d on the substrate 1 side is formed on the corner of the substantially square flat portion so as to become the N pole, and the surface of the fourth magnet 5d is formed on the substrate 1 side by the well-known means such as bonding. Is fixed to the vibration base 3.

The first to fourth coils 6a, 6b, 6c, 6
d is an air-core coil, which is bonded to the substrate 1 at a position facing the above-described first to fourth magnets 5a, 5b, 5c, 5d. , The aforementioned first to fourth gnets 5a, 5b, 5
c and 5d have a shape with a slight gap between the surface of the substrate 1 side.

The second vibrator 7 is made, for example, by lathing brass, and has one end fixed to the second vibrating base 8 by means such as press fitting.

The second vibration base 8 is made of, for example, a phosphor bronze plate, and has a substantially square flat portion to which magnets 9a to 9d are fixed, and fifth to fifth flat portions provided at the centers of the respective sides of the square. Eight legs 8a, 8b, 8c, 8d,
The distal ends of the fifth to eighth legs 8a, 8b, 8c, 8d are fixed to the substrate 1, respectively.

The fifth to eighth piezoelectric elements 9a, 9b, 9c,
9d is made of, for example, PZT, has a substantially rectangular shape, and is polarized in the thickness direction.
Are fixed to the legs 8a to 8d by bonding, respectively.

The first and second piezoelectric elements 4a and 4b are
A signal corresponding to the inclination of the transducer 2 in the X-axis direction, which is the detection axis direction, is output. The third and fourth piezoelectric elements 4c, 4b are connected to the transducer in the Y-axis direction, which is the second detection axis direction. And outputs a signal corresponding to the inclination of 2.

The fifth to eighth magnets 10a, 10b,
10c and 10d are made of, for example, a ferrite-based plastic magnet, are magnetized in the thickness direction, and, for example, such that the poles on the surface on the substrate 1 side are opposite to adjacent poles. The surface of the fifth magnet 10a on the substrate 1 side is the N pole, the surface of the sixth magnet 10b (not shown in FIG. 1) on the substrate 1 side is the S pole, and the seventh magnet 1
The surface of the substrate 1 on the side of the substrate 1 has an N pole, and the eighth magnet 10
The surface of d on the substrate 1 side is fixed to the second vibration base 8 by a well-known means such as adhesion at each corner of a substantially square flat portion so as to be an S pole.

Fifth to eighth coils 11a, 11b, 11
The air-core coils c and 11d are bonded to the substrate 1 at positions facing the above-described fifth to eighth magnets 10a, 10b, 10c and 10d, and are fixed on the substrate 1 by bonding. At this time, the first to fifth magnets 10a, 10b, 10c, and 10d have a shape in which a slight gap is formed between the surfaces on the substrate 1 side. The first to eighth coils have first and second terminals, respectively. When current flows in the same direction, for example, from the first terminal to the second terminal, the first to eighth coils pass through the magnet. On the facing side, it is fixed on the substrate 1 so that the same poles are excited.

The first vibrator 2 and the second vibrator 7 have substantially the same resonance frequency in the bending direction, and have the first vibrator 2, the first vibrating base 3, and the first vibrating base. The resonance frequency of the vibration mode in the direction in which the vibrator 2 of the first vibrating body 400 falls, which is constituted by the fourth to fourth magnets 5a to 5d and the first to fourth pressure elements 4a to 4d, It is matched with the resonance frequency in the bending direction. The setting of the resonance frequency is performed by appropriately setting the plate thickness of the first vibration base 3 and the width and length of the legs 3a to 3d.

Similarly, the second vibrator 7, the second vibration base 8, the fifth to eighth magnets 10a to 10d, the fifth
The resonance frequency of the vibration mode in the direction in which the second vibrator 7 of the second vibrating body 410 falls, which is constituted by the eighth to eighth piezoelectric elements 9a to 9d, also matches the resonance frequency of the vibrator in the bending direction. ing. The setting of the resonance frequency in this case is also performed by appropriately setting the thickness of the second vibration base 8 and the width and length of the legs 8a to 8d.

Next, a circuit configuration according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a block diagram showing the drive circuit 12 and the signal detection unit (note that,
FIG. 3 shows the detection circuit 13.
FIG.

The drive circuit 12 is a drive circuit for supplying a current to a coil at a predetermined frequency and a predetermined phase.
The oscillation circuit 14, the sine wave generation circuit 15, the first drive circuit 16, the cosine wave generation circuit 17, and the second drive circuit 18 are provided on the substrate 1.

The oscillating circuit 14 is a known oscillating circuit, and its output terminal is connected to the respective input terminals of the sine wave generating circuit 15 and the cosine wave generating circuit 17.

The sine wave generating circuit 15 is a circuit that generates a sine wave based on a pulse signal input to an input terminal, such as a frequency divider using a flip-flop circuit. It is connected to the input terminal of one drive circuit 16.

The first drive circuit 16 is a circuit that amplifies a signal input to an input terminal with a predetermined gain and supplies the signal to the above-described coil as electric power for driving the first and second vibrators. .

The cosine wave generation circuit 17 generates a cosine wave having a phase different from that of the sine wave generation circuit 15 by 90 degrees based on the pulse signal input to the input terminal, for example, by using a flip-flop circuit. The output terminal is connected to the input terminal of the second drive circuit 18.

The second drive circuit 18 is a circuit that amplifies a signal input to the input terminal with a predetermined gain and supplies the signal to the above-described coil as electric power for driving the first and second vibrators.

The output terminal of the first drive circuit 16 is connected to the first terminal 6a-1 of the first coil 6a and the first terminal 11b-1 of the sixth coil 11b. It is connected so as to be energized.
The output terminal of the drive circuit 18 is connected to the first terminal 6b-1 of the second coil 6b and the first terminal 11a-1 of the fifth coil 11a, so that the coil is energized. Have been.

In the driving circuit 12 according to the first embodiment of the present invention shown in FIG. 2, the oscillation circuit 14 includes a sine wave generation circuit 15 and a cosine wave generation circuit Is a known oscillation circuit whose oscillation frequency is set to a frequency that generates a signal at a frequency that causes the vibrators 400 and 410 to resonate in a direction in which the respective vibrators 2 and 7 are inclined. Sin
The wave generation circuit 15 and the cos wave generation circuit 17 are connected to respective input terminals.

In FIG. 2, the signal detectors indicated by portions not surrounded by broken lines are first and second signal synthesizing circuits 19 and 20.
And first and second inverting circuits 21 and 22. The differential amplifier circuits 23 to 26 are included in a detection circuit 13 described later.

The first and second signal synthesizing circuits 19 and 20 are:
It is a well-known addition circuit, and includes first and second inversion circuits 21 and
2 is a well-known inverting amplifier circuit.

The input terminal of the first signal synthesizing circuit 19 is connected to the output terminal of the sine wave generating circuit 15 and the output terminal of the cosine wave generating circuit 17.
By processing these signals, outputs a signal xin1 corresponding to the X component of the excitation signal to the first vibrating body 400 from the output terminal Vxin1.

Since the second vibrating body 410 is spatially vibrated with respect to the first vibrating body 400 with a phase shift of 180 degrees in the X-axis direction, the second inverting circuit 22 Is
The signal xin corresponding to the X component of the excitation signal to the second vibrating body 410 is inverted by inverting the output signal of the first signal combining circuit 19.
2 is output from the output terminal Vxin2.

The input terminal of the second signal synthesizing circuit 20 is connected to the output terminal of the aforementioned cosine wave generating circuit 17 and the first inverting circuit 2.
1 and the input terminal of the first inversion circuit 21 is connected to the sine wave generation circuit 15 described above.
Outputs a signal obtained by inverting the in-wave. By processing these signals, the second signal synthesizing circuit 20 outputs signals yin1 and yin2 corresponding to the Y component of the excitation signal to the first and second vibrators 400 and 410 to output terminals Vyin1 and Vyin2.
Output more.

The signal detector processes the output signal of the sine wave generation circuit 15 and the output signal of the cosine wave generation circuit 17 in the drive circuit 12 and outputs the signals to the first and second vibrators 2 and 2, respectively.
7, the excitation signals in the x and y axis directions are generated, and these excitation signals in the x and y axis directions are connected to terminals Vxin1, Vyin1, Vxin2,
It is transmitted to a detection circuit 13 described later via Vyin2.

Next, the operation of the drive circuit 12 according to the first embodiment and the vibration of the first and second vibrators 2 and 7 will be described.

First drive circuit 16 in drive circuit 12
Is the first terminal 6a-1 of the first coil 6a.
To the second terminal 6a-2 of the first coil 6a.
Is connected to the second terminal 6c-2 of the third coil 6c, and the first terminal 6c-1 of the third coil 6c is grounded to the ground level.

With such connection, magnetic fields of opposite polarities are excited on the magnet-side surfaces of the first and third coils 6a and 6c, respectively, and the output terminal of the first drive circuit 16, for example. Is a positive output, as described above, the first, third, fifth, and seventh magnets 5a, 5a,
Since the polarities of 5c, 10a, and 10c and the second, fourth, sixth, and eighth magnets 5b, 5d, 10b, and 10d are opposite, the first coil 6a attracts the first magnet 5a. Then, the third coil 6c repels the third magnet 5c, and the vibrator 1 is inclined in the direction A in FIG.

The output terminal of the first drive circuit 16 in the drive circuit 12 is connected to the second terminal 11b-2 of the sixth coil 11b, and is connected to the first terminal 11b- of the sixth coil 11b. 1 is the first terminal 11 of the eighth coil 11d.
d-1 and the terminal 11d- of the eighth coil 11d.
2 is connected to the ground level.

With such connection, magnetic fields of opposite polarities are excited on the magnet-side surfaces of the sixth and eighth coils 11b and 11d, respectively. When the terminal is a positive output, as described above, the first, third, fifth, and seventh magnets 5
a, 5c, 10a, 10c and the second, fourth, sixth, eighth
Since the polarities of the magnets 5b, 5d, 10b, and 10d are opposite, the sixth coil 11b is connected to the sixth magnet 1b.
0b is attracted, the eighth coil 11d repels the eighth magnet 10d, and the vibrator 7 is inclined in the -B direction (the direction opposite to the B direction) in FIG.

The output terminal of the second drive circuit 18 in the drive circuit 12 is connected to the first terminal 6 of the second coil 6b.
b-1 and the second terminal 6b of the second coil 6b
-2 is connected to the second terminal 6d-2 of the fourth coil 6d, and the first terminal 6d-1 of the fourth coil 6d is connected to the ground level.

By connecting in this manner, magnetic fields of opposite polarities are excited on the magnet-side surfaces of the second and fourth coils 6b and 6d, respectively. Assuming that the terminal has a positive output, as described above, the first, third, fifth, and seventh magnets 5
a, 5c, 10a, 10c and the second, fourth, sixth, eighth
Since the polarities of the magnets 5b, 5d, 10b, and 10d are opposite, the second coil 6b repels the second magnet, and the fourth coil 6d attracts the fourth magnet 5d, and the vibrator 1 is inclined in the direction B in FIG.

The output terminal of the second drive circuit 18 in the drive circuit 12 is connected to the second terminal 11a-2 of the fifth coil 11a.
1a-1 is a first terminal 11c- of the seventh coil 11c.
1 and the second terminal 11c of the seventh coil 11c.
-2 is connected to the ground level.

By connecting in this manner, magnetic fields of opposite polarities are excited on the magnet-side surfaces of the fifth and seventh coils 11a and 11c, respectively. When the terminal has a positive output, the fifth coil 11a repels the fifth magnet 10a, the seventh coil 11c attracts the seventh magnet 10c, and the vibrator 7 moves in the -A direction in FIG. (Reverse direction to A direction)
It has become inclined to.

When the power supply (not shown) of the sensor is turned on and the oscillation circuit 14 outputs a pulse of a predetermined frequency,
The n-wave generation circuit 15 generates a sine wave and a cosine wave generation circuit 17
Generates a cosine wave, and energization of the coil is started by the first and second drive circuits 16 and 18, respectively.

When a sine wave and a cosine wave are applied to the coil from the first drive circuit 16 and the second drive circuit 18, respectively, the first vibrator 400 and the second vibrator 410 are applied as described above. Then, the relationship between the coil and the magnet,
In FIG. 1, when the same energization is performed, the inclination directions in the direction B are reversed, and the resonance frequencies of the first and second vibrating bodies 400 and 410 are the same. The first vibrating body 400 and the second vibrating body 410 resonate with the input signal, and the first and second vibrators 2 and 7 rotate in directions opposite to each other.

Further, in the present embodiment, since the coils are connected as described above, the positional phase difference when the first vibrator 2 and the second vibrator 7 turn is represented by FIG.
Are 180 degrees in the X-axis direction, and have the same phase in the Y-axis direction.

Next, the detection circuit 13 according to the first embodiment will be described in detail with reference to FIGS.

In FIG. 2, 4a, 4b, 4c, 4d,
1, 9a, 9b, 9c and 9d are piezoelectric elements attached to the legs of the first and second vibration bases 3 and 8 in order to detect the inclination of the vibrator, as described in FIG. When the legs of the first and second vibration bases 3 and 8 are bent, a predetermined voltage is output according to the amount.

The first differential amplifier circuit 23 is a well-known differential amplifier circuit having first and second input terminals and outputting a difference between signals input to the first and second input terminals. The first and second input terminals are connected to first and second piezoelectric elements 4a and 4b for detecting the inclination of the first vibrator 2 in the X-axis direction. The difference between the output signals of the piezoelectric elements 4a and 4b is obtained and output from the output terminal Vx1 as a signal x1 corresponding to the tilt of the first vibrator 2 in the X-axis direction.

The second differential amplifier circuit 24 is a well-known differential amplifier circuit having first and second input terminals and outputting a difference between signals input to the first and second input terminals. The first and second input terminals are connected to fifth and sixth piezoelectric elements 9a and 9b for detecting the inclination of the second vibrator 7 in the X-axis direction. The difference between the output signals of the piezoelectric elements 9a and 9b is obtained and output from the output terminal Vx2 as a signal x2 corresponding to the tilt of the second vibrator 7 in the X-axis direction.

The third differential amplifier circuit 25 is a well-known differential amplifier circuit having first and second input terminals and outputting a difference between signals input to the first and second input terminals. The first and second input terminals are connected to first and second piezoelectric elements 4a and 4b for detecting a tilt of the first vibrator 2 in the Y-axis direction. The difference between the output signals of the piezoelectric elements 4a and 4b is obtained and output from the output terminal Vy1 as a signal y1 corresponding to the inclination of the first vibrator 2 in the Y-axis direction.

The second differential amplifier circuit 26 is a well-known differential amplifier circuit having first and second input terminals and outputting a difference between signals input to the first and second input terminals. The first and second input terminals are connected to fifth and sixth piezoelectric elements 9a and 9b for detecting the inclination of the second vibrator 7 in the Y-axis direction. The difference between the output signals of the piezoelectric elements 9a and 9b is obtained and output from the output terminal Vy2 as a signal y2 corresponding to the tilt of the second vibrator 7 in the Y-axis direction.

FIG. 3 is a circuit diagram showing the differential amplifier circuits 23 to 23 to 23 shown in FIG.
26 is a block diagram illustrating the detection circuit 13 excluding 26. FIG.
Reference numerals 27, 28, 29, and 30 denote first, second, third, and fourth high-pass filters, which are well-known high-pass filters that pass only high-frequency components to input signals. 31,3
Reference numerals 2, 33, and 34 denote first, second, third, and fourth one-period averaging circuits, respectively.
A signal corresponding to the average value between cycles is output.

Reference numerals 35 and 36 denote first and second adders, which output signals obtained by adding the input signals to each other. Reference numeral 37 denotes a third addition circuit, which outputs a signal obtained by adding the input signals to each other. 38 is a first DC offset circuit,
The input signal is output after being offset by a predetermined voltage value.
Reference numeral 39 denotes a first gain adjustment circuit, which outputs a signal obtained by amplifying an input signal at a predetermined amplification factor. Reference numeral 40 denotes a first subtraction circuit, which outputs a signal obtained by subtracting the signal input to the second input terminal from the signal input to the first input terminal.
Reference numeral 41 denotes a first signal processing circuit that performs signal processing based on a signal input to the second input terminal and outputs the first input signal. Reference numeral 42 denotes a second gain adjustment circuit, which outputs a signal obtained by amplifying an input signal at a predetermined amplification factor. Reference numeral 43 denotes a fourth addition circuit, which outputs a signal obtained by adding the input signals to each other. 44 is a first low-pass filter.

Reference numeral 45 denotes a second gain adjustment circuit, which outputs a signal obtained by amplifying an input signal at a predetermined amplification factor. 46,
Reference numerals 47, 48, and 49 denote second, third, fourth, and fifth signal processing circuits, which output signals obtained by subjecting input signals to predetermined processing. Reference numerals 50, 51, 52, and 53 denote second, third, fourth, and fifth subtraction circuits, and reference numeral 54 denotes a first variable gain adjustment circuit, which converts a signal input to an input terminal into a signal input to a control terminal. And outputs a signal amplified at a predetermined amplification rate determined by the above. 55 is a fifth high-pass filter, 56 is a second low-pass filter, 57 is a second variable gain adjustment circuit, which converts a signal input to an input terminal into a predetermined amplification factor determined by a signal input to a control terminal. And outputs the amplified signal. 58 is a sixth high-pass filter, 59 is a third low-pass filter, 6
0 and 61 are first and second averaging circuits, 62 is a sixth subtraction circuit, and 63 is a fourth low-pass filter.

Next, the operation of the sensor according to the first embodiment of the present invention will be described with reference to FIGS.

When the power of the sensor is turned on and the oscillation circuit 14 in the drive circuit 12 outputs a pulse, the first coil attracts and repels the magnet, thereby causing the first coil to repel.
Vibrator 2 starts the motion of a vibration component whose inclination in the X-axis direction is 90 degrees ahead of the inclination in the Y-axis direction. Such a movement is a turning movement of the first vibrator 2, and in the present embodiment, the arrangement of the coil and the magnet and the connection of the coil make the first vibrator 2 in FIG. It turns counterclockwise when viewed from above the oscillator. Similarly, the second vibrator starts to move a vibration component whose inclination in the X-axis direction is delayed by 90 degrees from that in the Y-axis direction. Such a movement is a turning movement of the second vibrator. In the present embodiment, the arrangement of the coil and the magnet and the connection of the coil described above cause the second vibrator 7 to vibrate in FIG. Make a clockwise turn as seen from above the child.

Further, by the arrangement of the coils and the magnets and the connection of the coils, the turning motions of the first and second vibrators 2 and 7 have the same phase of the vibration component in the Y-axis direction as described above. The phase of the vibration component in the X-axis direction makes a 180-degree turning motion.

When the turning motion of the vibrator is expressed by the following equation,
Coordinates (x1, y1) of the tip of the vibrator 2 and the second
The coordinates (x2, y2) of the tip of the vibrator 7 are (x1, y1) = (r · cosωt, r · sinωt) (x2, y2) = (− r · cosωt, r · sinωt). Here, r is a constant indicating the turning radius.

In this embodiment, the output terminals Vx1 and Vx1 shown in FIGS.
Vy1, Vx2, and Vy2 are the first vibrator 2 respectively.
(X1, y1) at the tip of the second vibrator 7
, A signal corresponding to the coordinates (x2, y2) of the tip of is generated.

Here, the acceleration ax in the X-axis direction, the acceleration ay in the Y-axis direction, the acceleration az in the Z-axis direction, the angular velocity ωx around the X-axis, the angular velocity ωy around the Y-axis, and the angular velocity ωz around the Z-axis
, The coordinates (x1, y1) and (x2, y2) are represented by x1 = (r + B · C · az) × (1 + A · ωz + A · C · ωx · cosωt), where A, B and C are constants, respectively. cosωt−B × az (1) y1 = (r + B · C · az) × (1 + A · ωz + A · C · ωy · sinωt) × sinωt−B · ay (2) x2 = (r + B · C · az) ) × (1−A · ωz−A · C · ωx · cosωt) × cosωt−B · ax (3) y2 = (r + B · C · az) × (1−A · ωz−A · C · ωy・ Sinωt) × sin (−ωt) −B · ay (4)

As described above, signals corresponding to these coordinates are output from the output terminals Vx1, Vy1, Vx2, Vy2 in FIG.
Occurs.

The first high-pass filter 27 has an output terminal V
Since a DC component is cut from the signal x1 generated at x1, and the output signal is averaged by the first one-cycle averaging circuit 31, the output signal of the first one-cycle averaging circuit 31 is (1 + B · C · az) ) × (1A · ωz).

Similarly, the second high-pass filter 28 cuts the DC component from the signal y1 generated at the output terminal Vy1, and the output signal is averaged by the second one-cycle averaging circuit 32. The output signal of the one-cycle averaging circuit 32 is (1 + B · C · az) × (1 + A · ωz).

The third high-pass filter 29 has an output terminal V
Since a DC component is cut from the signal x2 generated at x2 and its output signal is averaged by the third one-cycle averaging circuit 33, the output signal of the third one-cycle averaging circuit 33 is (1 + B · C · az) ) × (1−A · ωz).

Similarly, the fourth high-pass filter 30 cuts the DC component from the signal y2 generated at the output terminal y2, and the output signal is averaged by the fourth one-cycle averaging circuit 34. The output signal of the one-cycle averaging circuit 34 is (1 + B · C · az) × (1−A · ωz).

The first addition circuit 35 adds the output signals of the first and second one-cycle averaging circuits 31 and 32, and the output is 2 × (1 + B · C · az) × (1 + A · ωz). Becomes

The second adder circuit 36 includes third and fourth
The output signals of the one-cycle averaging circuits 33 and 34 are added, and the output is 2 × (1 + B · C · az) × (1−A · ωz).

The third adder circuit 37 includes a first adder circuit 3
5 and the output signal of the second adding circuit 36, and the output is 4 × (1 + B · C · az). This signal is offset by a first DC offset circuit 38 and amplified by a first gain adjustment circuit 39 at a predetermined amplification rate, so that a signal corresponding to the acceleration az in the Z-axis direction applied to the sensor is applied to a terminal Vaz. Obtainable.

On the other hand, the first subtraction circuit 40 subtracts the output signal of the second addition circuit 36 from the first addition circuit 35,
The output is 4 × (1 + B · C · az) × A · ωz. This signal is converted by a first processing circuit 41 based on az which is an output signal of the first gain adjustment circuit 39,
Divide by “4 × (1 + B · C · az)”
A signal corresponding to the angular velocity ωz about the Z axis applied to the sensor at the terminal Vωz can be obtained.

The fourth adder 43 calculates the sum of x1 and x2, and the output signal is (r + B · C · az) × cosωt−2 · B · ax. A DC component is cut from the output signal by a first low-pass filter 44, and the sign and gain are adjusted by a third gain adjustment circuit 45, whereby the acceleration applied to the terminal Vax in the X-axis direction is applied to the sensor. a
A signal corresponding to x can be obtained.

The second signal processing circuit 46 calculates the vibration signal xin1 of the first vibrating body 400 in the X-axis direction and the first signal
, The acceleration az in the Z-axis direction output from the gain adjustment circuit 39, the angular velocity ωz about the Z-axis output from the second gain adjustment circuit 42, and the X-axis direction output from the third gain adjustment circuit 45. (R + B · C · az) × (1 + A · ωz) × cosωt−
A signal corresponding to B · ax is generated.

The second subtraction circuit 50 is provided for the first vibrating body 40
An output signal of the second signal processing circuit 46 is subtracted from a signal x1 corresponding to an inclination in the X-axis direction of 0 (corresponding to the coordinates of the tip of the vibrator).

The first variable gain adjustment circuit 54 outputs the first gain adjustment circuit 39 to the output of the second subtraction circuit 50.
Based on the signal az input from (r + B · C ·
az) × A · C ”, and the output signal is (x1− (r + B · C · az) × (1 + A · ωz) × c
osωt−B · ax) / (r + B · C · az) · A · C), which corresponds to ωx · cos ² ωt according to the equation (1).

The fourth signal processing circuit 48 calculates xin2, which is the vibration signal of the second vibrating body 410 in the X-axis direction, and the acceleration az in the Z-axis direction output from the first gain adjustment circuit 39 described above. , Z output from the second gain adjustment circuit 42
Based on the angular velocity ωz about the axis and the acceleration ax in the X-axis direction output from the third gain adjustment circuit 45, (r + B · C · az) × (1−A · ωz) × cosωt−
A signal corresponding to B · ax is generated.

The fourth subtraction circuit 52 includes a second vibrating body 41
An output signal of the third signal processing circuit 48 is subtracted from a signal x2 corresponding to a tilt in the X-axis direction of 0 (corresponding to the coordinates of the tip of the vibrator).

The second variable gain adjustment circuit 57 applies the first gain adjustment circuit 39 to the output of the fourth subtraction circuit 52.
Based on the signal az input from (r + B · C ·
az) × A · C ”, and the output signal is (x2-((r + B · C · az) × (1−A · ωz) ×
cosωt-B · ax)) / (r + B · C · az) · A ·
C), which corresponds to −ωx · cos ² ωt from the equation (3).

The sixth subtraction circuit 62 calculates the difference between the output signals of the first variable gain adjustment circuit 54 and the second variable gain adjustment circuit 57, and outputs the output signal of the sixth subtraction circuit 62 to the fourth variable gain adjustment circuit 62.
Of the terminal Vω
It is possible to obtain a signal corresponding to the angular velocity ωx about the X axis applied to the sensor at x.

The third signal processing circuit 47 calculates the excitation signal yin1 of the first vibrator 400 in the Y-axis direction and the first signal
(R + B · C · az) × (1 + A ·) based on the Z-axis acceleration az output from the gain adjustment circuit 39 and the angular velocity ωz about the Z-axis output from the second gain adjustment circuit 42. ωz) × sinωt is generated.

The third subtraction circuit 51 is provided for the first vibrating body 40
An output signal of the second signal processing circuit 47 is subtracted from a signal y1 corresponding to a tilt in the Y-axis direction of 0 (corresponding also to the coordinates of the tip of the vibrator).・ C ・ az) × A ・ C ・ ωy ・ sin ² ω−B ・
ay.

The fifth high-pass filter 55 removes the DC component of the output signal of the third subtraction circuit 51, and the output signal is connected to the input terminal of the first averaging circuit 60.

The second low-pass filter 56 removes the AC component of the output signal of the third subtraction circuit 51, and the output signal is connected to the input terminal of the second averaging circuit 61.

The fourth signal processing circuit 49 converts the excitation signal yin2 of the second vibrating body 410 in the Y-axis direction into the first signal
Based on the acceleration az in the Z-axis direction output from the gain adjustment circuit 39 and the angular velocity ωz about the Z-axis output from the second gain adjustment circuit 42, − (r + B · C · az) × (1 −A · ωz) × sinωt is generated.

The fifth subtraction circuit 53 includes a second vibrating body 41
The output signal of the fourth signal processing circuit 49 is subtracted from the signal y2 corresponding to the inclination in the Y-axis direction of 0 (corresponding also to the coordinates of the tip of the vibrator), and the result is given by (r + B)・ C ・ az) × A ・ C ・ ωy ・ sin ² ω−B ・
ay.

The sixth high-pass filter 58 removes the DC component of the output signal of the fifth subtraction circuit 53, and the output signal is connected to the input terminal of the first averaging circuit 60.

The third low-pass filter 59 removes the AC component of the output signal of the fifth subtraction circuit 53, and the output signal is connected to the input terminal of the second averaging circuit 61.

The first averaging circuit 60 averages the input signal, removes high-frequency components, amplifies the signal at a predetermined amplification factor, and outputs the result to an output terminal.

The signal input from the fifth high-pass filter 55 to the first averaging circuit 60 corresponds to (r + B · C · az) × A · C · ωy · sin ² ω according to equation (2). Further, the signal input from the sixth high-pass filter 59 to the second averaging circuit 60 also becomes (r + B · C · az) × A · C · ωy · sin ² ω from the equation (4). The terminal Vωy via the first averaging circuit 60
A signal corresponding to the angular velocity ωy about the Y axis applied to the sensor can be obtained.

The second averaging circuit 61 averages the input signal, amplifies the signal at a predetermined amplification factor, and outputs the result to an output terminal.

The signal input from the second low-pass filter 56 to the second averaging circuit 61 corresponds to −B · ay according to the equation (2), and the third low-pass signal is supplied to the second averaging circuit 61. Since the signal input from the filter 59 also becomes −B · ay according to the equation (4), the terminal Vay is output via the second averaging circuit 61.
A signal corresponding to the acceleration ay applied to the sensor in the Y-axis direction can be obtained.

(Second Embodiment) In the above-described second embodiment of the present invention, the first vibrator 4
00, a signal x1 corresponding to the tilt in the X-axis direction, a signal y1 corresponding to the tilt in the Y-axis direction, and X
The signal x2 corresponding to the tilt in the axial direction and the signal y2 corresponding to the tilt in the Y-axis direction are passed through a high-pass filter, passed through a one-cycle averaging circuit, and then passed through the first and second vibrators 40.
The sum of signals in the X-axis direction and the Y-axis direction of 0 and 410 is obtained, and the acceleration in the Z-axis direction and the angular velocity around the Z-axis can be detected based on the sum signal of each transducer. A signal x1 corresponding to the tilt in the X-axis direction, a signal y1 corresponding to the tilt in the Y-axis direction, and a signal corresponding to the tilt in the X-axis direction of the second vibrator 410, respectively. x2 and a signal y2 corresponding to the inclination in the Y-axis direction are
After passing through the high-pass filter, the first and second vibrators 4
The sum of signals in the X-axis direction and the Y-axis direction of each of 00 and 410 is taken and passed through a one-cycle averaging circuit. Thereafter, based on the sum signal of each vibrator, the acceleration in the Z-axis direction and Angular velocity can also be detected.

FIG. 4 is a block diagram according to a second embodiment of the present invention in which a detection circuit is configured as described above.

Referring to FIG. 4, a first embodiment of the present invention is described.
The same reference numerals are given to the same components as those of the embodiment, and the description will be omitted. In the second embodiment of the present invention,
The vibrating body is the same as that of the first embodiment of the present invention shown in FIG.

In FIG. 4, reference numeral 301 denotes a first addition circuit, and 302 denotes a second addition circuit. The first and second addition circuits 301 and 302 have first and second input terminals and one output terminal, respectively, and add signals input to the first and second input terminals to each other, Output to the output terminal. Reference numerals 303 and 304 denote first and second one-cycle averaging circuits, respectively.
A signal substantially corresponding to the average value between cycles is output.

As described in the first embodiment,
The acceleration ax in the X-axis direction and the acceleration a in the Y-axis direction
acceleration az in the y- and Z-axis directions, angular velocity ωx about the X-axis, X
When the angular velocity ωy about the axis and the angular velocity ωz about the Z axis act, the coordinates (x1, y1) and (x2, y2) become
Assuming that A, B, and C are constants, x1 = (r + B · C · az) × (1 + A · ωz + A · C · ωx · cosωt) × cosωt−B · ax (5) y1 = (r + B · C · az) × (1 + A · ωz + A · C · ωy · sinωt) × sinωt−B · ay (6) x2 = (r + B · C · az) × (1−A · ωz−A · C · ωx · cosωt) × cosωt −B · ax (7) y2 = (r + B · C · az) × (1−A · ωz−A · C · ωy · sinωt) × sin (−ωt) −B · ay (8) Become.

These signals are the first. Second and third. 4th
, And their output signals V ₂₇ , V ₂₈ , V ₂₉ , and V ₃₀ are given by: V ₂₇ = (r + B · C · az) × (1 + A · ωz + A · C · ωx × cosωt) × cosωt V ₂₈ = (r + B · C · az) × (1 + A · ωz + A · C · ωy × sinωt) × sinωt V ₂₉ = (r + B · C · az) × (1−A · ωz−A · C) Ωx × cosωt) × cosωt V ₃₀ = (r + B · C · az) × (1−A · ωz−A · C · ωy × sinωt) × sin (−ωt)

The first addition circuit 301 adds the input signals from the first and second high-pass filters 27 and 28, and the output signal V ₃₀₁ is V ₃₀₁ = (r + B · C · az) × (1 + A)・ Ωz) ×
(Cosωt + sinωt) + A · C × (ωx · cos ² ωt
+ Ωy · sin ² ωt), and the second addition circuit 302 adds the input signals from the third and fourth high-pass filters 29 and 30, and
The output signal V ₃₀₂ is given by: V ₃₀₂ = (r + B · C · az) × (1−A · ωz) ×
(Cosωt + sinωt) −A · C × (ωx · cos ² ωt
+ Ωy · sin ² ωt). These signals are first and second one-cycle averaging circuit 3
On average at 03, ₃₀₄ , the respective outputs V ₃₀₃ , V
₃₀₄ is: V ₃₀₃ = (r + B · C · az) × (1 + A · ωz) V ₃₀₄ = (r + B · C · az) × (1−A · ωz), and these signals are converted to the first in the above-described embodiment. The signals are added by a third adder circuit 37 similar to the embodiment, the signal is offset by a first DC offset circuit 38, and is amplified by a first gain adjustment circuit 39 at a predetermined amplification factor.
A signal corresponding to the acceleration az in the Z-axis direction applied to the sensor at the terminal Vaz can be obtained.

The signals are subtracted from the output signals V ₃₀₃ and V ₃₀₄ of the first and second one-cycle averaging circuits ₃₀₃ and ₃₀₄ by a first subtraction circuit 40 in the same manner as in the first embodiment. In the first processing circuit 41, the first gain adjustment circuit 39
Based on the output signal az of “4 × (1 + B · C
. Az) ”, and amplifies the signal at a predetermined gain in the second gain adjustment circuit 42 to obtain the terminal Vω
It is possible to obtain a signal corresponding to the angular velocity ωz about the Z axis applied to the sensor in z.

In the above-described second embodiment of the present invention, the number of one-period averaging circuits used can be reduced, so that it is less likely to be affected by circuit variations.

(Third Embodiment) In the first and second embodiments of the present invention described above, the detection signal is obtained by performing signal processing on the change in the vibration state of the vibrator. It is also possible to use a so-called servo-type sensor that controls the child to vibrate at a constant rate and processes the control signal to obtain an angular velocity signal and an acceleration signal.

Furthermore, the first and second embodiments of the present invention described above are based on the premise that they are manufactured by ordinary machining. However, the sensor according to the present invention uses semiconductor manufacturing technology. It can also be manufactured using a so-called micromachining technology.

FIG. 5 is a perspective view of a sensor according to a third embodiment of the present invention. In FIG. 5, 101 is a silicon substrate, 102 is a first vibrator, 103 is a first vibration base, 104a , 104b, 104c, 104d are spring portions 105a, 105 for elastically supporting the first vibrator 102, which is a weight portion, via the first vibration base 103.
b, 105c, 105d are movable electrodes, 107 is a second vibrator, 108 is a second vibration base, 109a, 109
b, 109c and 109d denote spring portions for elastically supporting the second vibrator 107, which is a weight portion, via the second vibration base 108, 110a, 110b, 110c and 110
d is a movable electrode, 112 is a drive circuit, and 113 is a detection circuit.

The substrate 101 is formed by forming a circuit on a silicone wafer by a CMOS process and performing surface micromachining by etching and film forming. A first vibration base 103 is provided on the substrate 101. , First to fourth spring portions 104a to 104
d, first to fourth movable electrodes 105a to 105d, first
To fourth fixed (driving) electrodes 106a to 106d (not shown), a second vibration base 108, first to fourth spring portions 109a to 109d, first to fourth movable electrodes 110a.
To 110d, and the fifth to eighth fixed electrodes 111a to 111d.
111d (not shown) is provided, and the first vibration base 103 is elastically supported by the substrate 101 by first to fourth spring portions 104a to 104d. The second vibration base 108 is connected to the fifth to eighth spring portions 1.
09a to 109d elastically support the substrate 101.

The first and second vibration bases 103 and 108 have first and second vibration bases 103 and 108, for example, made by applying the LIGA process.
The second vibrators 102 and 107 are fixed by means such as adhesion or bonding.

First to eighth spring portions 104a to 104d for elastically supporting the first and second vibrators 102 and 107,
Each of 09a to 109d has a sharp shape bent right and left with respect to the length direction, so that the amount of inclination of the vibrators 102 and 107 can be increased by a small force. That is, a large vibration can be given.

Further, a drive circuit 112 and a detection circuit 113 are provided on the substrate 101 by a CMOS process. A power supply terminal and terminals for outputting an angular velocity signal and an acceleration signal are provided on the substrate 101.
It is not shown in FIG.

Further, the first to fourth movable electrodes 150a to 150a
On the surface opposite to the first vibrator 102 of 150d, first to fourth movable electrodes 150a-1 and 150a-1 (not shown) are respectively provided.
50b-1, 150c-1, and 150d-1 are provided, and each electrode is opposed to the first to fourth fixed electrodes 106a to 106d (not shown) via a slight gap. , The first to fourth 150a-1, 15
0b-1, 150c-1, and 150d-1 are electrically connected so as to have a constant voltage.
To the fourth fixed electrodes 106a to 106d
2, a signal of a natural frequency at which the vibrator 102 makes a turning motion is input, and the first vibrator 102
Through fourth movable electrodes 150a-1, 150b-1, 15
0c-1, 150d-1 and the first to fourth fixed electrodes 10
The swirling motion is caused by the Coulomb force acting between 6a to 106d.

Similarly, the fifth to eighth movable electrodes 110a
To 110d, on the surface opposite to the second vibrator 107, fifth to eighth movable electrodes 110a-1 (not shown),
110b-1, 110c-1, and 110d-1 are provided, and each of the electrodes is opposed to fifth to eighth fixed electrodes 111a to 111d (not shown) via a slight gap. And the fifth to eighth 110a-1,
110b-1, 110c-1, and 110d-1 are electrically connected so as to have a constant voltage, and fifth to eighth fixed electrodes 111a to 111d (not shown) are connected to a drive circuit 112. , A signal of a natural frequency at which the vibrator 107 makes a revolving motion is input, and the second vibrator 107
The fifth to eighth movable electrodes 110a-1, 110b-1,
It is swirled by the Coulomb force acting between 110c-1, 110d-1 and the fifth to eighth fixed electrodes 111a to 111d.

The first to eighth spring portions are respectively provided with first to eighth piezoresistive elements 104a-1 and 104a-1.
4b-1, 104c-1, 104d-1, 109a-
1, 109b-1, 109c-1, and 109d-1 are provided by means of, for example, diffusing phosphorus on silicon, and the first and second elements are detected and compared by detecting and comparing the resistance values of the piezoresistive element. The inclinations of the transducers 102 and 107 in the directions A and B shown in FIG. 5 can be respectively detected.

In FIG. 5, reference numeral 401 denotes a first vibrator, and 411 denotes a second vibrator.

Next, a circuit according to a third embodiment of the present invention will be described with reference to FIG. The same parts as those in FIG. 5 are denoted by the same reference numerals.

In FIG. 6, reference numeral 114 denotes an oscillation circuit;
Is a sine wave generation circuit, 117 is a cosine wave generation circuit, 17
1,172,173,174 are servo circuits, 117,1
18, 119, and 120 are inverting amplifier circuits;
2,203,204,205,206,207,208
Is a bias resistor, 124, 125, 126, and 127 are differential amplifier circuits, 128, 129, 130, and 131 are arithmetic processing circuits, and 132 is an inverting amplifier circuit.

First, second, third and fourth servo circuits 17
Reference numerals 1,172,173,174 denote well-known servo circuits, which have first and second input terminals and output terminals, and output signals corresponding to a difference between signals input to the first and second inputs alone. Is output.

First, second, third and fourth differential amplifier circuits 1
Reference numerals 24, 125, 126, and 127 are well-known differential amplifier circuits having first and second input terminals and output terminals.
The first or second vibrator 1 is connected to each input terminal.
02 and 107 are connected to the piezoresistive effect element in the A direction or the B direction and the bias resistor, respectively, and these differential amplifier circuits are connected to the first or second vibrator 10 respectively.
A signal corresponding to 2,107 tilts in the A or B direction is output.

First, second, third and fourth arithmetic processing circuits 1
Reference numerals 28, 129, 130, and 131 denote well-known addition circuits that convert signals corresponding to the vibration trajectories of the first and second vibrating bodies 401 and 411 obtained as output signals of the servo circuit into signals in the direction of the piezoresistive element. This is a circuit that converts coordinates into signals. The inverting amplifier circuit 132 is a well-known inverting amplifier circuit.
Output the signal of sin.

Next, the operation of the third embodiment will be described.

When the oscillation circuit 114 starts oscillating, sin
The wave generation circuit 115 outputs a sine wave to the first and second servo circuits 171 and 172, and outputs the sine wave to the first and second servo circuits 17 and 172.
At this time, since the vibrator has not yet vibrated at this time and the input signals from the first and second arithmetic processing circuits 128 and 129 are 0, the first and second vibrators 1 and 172 respectively indicate
Fixed electrode 1 provided to vibrate 02, 107
Power supply to 06a, 106c, 111c, and 111a (not shown in FIG. 5) is started. When a voltage is applied to each of the fixed electrodes and a Coulomb force acts between the fixed electrodes and the movable electrodes, the first and second vibrators 102 and 107 are sinusoidally applied in the X-axis direction shown in FIG. Shaken.

Similarly, the cosine wave generating circuit 116 sets c
The os wave is output to the third and fourth servo circuits 173 and 174. At this time, the vibrator has not yet vibrated and the third and fourth servo circuits 173 and 174 perform the third and fourth arithmetic operations. Since the input signals from the processing circuits 130 and 131 are 0,
Fixed electrodes 106b, 106d, 11 provided for exciting the first and second vibrators 102, 107, respectively.
The energization to 1b and 111d (not shown in FIG. 5) is started. When a voltage is applied to each fixed electrode and a Coulomb force acts between the movable electrode and the movable electrode, the first and second vibrators 102 and 107 move co-axially in the Y-axis direction shown in FIG.
Excited in s shape. In the first vibrator 102 and the second vibrator 107, electrodes connected with the same polarity are X
On the opposite side of the vibrator in the axial direction, for example, the movable electrode 15
0a-1 and the fixed electrode 106a and the movable electrode 110
Since the fixed electrode 111c is opposed to c-1, the first and second vibrators rotate in directions opposite to each other.

When the first and second vibrators 102 and 107 start to turn, the first and second vibrators 102 and 10
7, the spring portions elastically supporting the vibration bases 103 and 108 are distorted, and the resistance value of the above-described piezoresistive effect element provided in the spring portions changes, and the first differential amplifier circuit 124 The second differential amplifier circuit 125 outputs a signal corresponding to the inclination of the vibrator 102 in the direction A, and the second differential amplifying circuit 125
The third differential amplifier circuit 126 outputs a signal corresponding to the gradient of the first transducer 102 in the B direction, and outputs a signal corresponding to the gradient of the first transducer 102 in the B direction. Is
A signal corresponding to the inclination of the second vibrator 107 in the B direction is output.

The first arithmetic processing circuit 128 receives a signal input from the first differential amplifier circuit 124 and corresponding to the inclination of the first vibrator in the direction A, and an input from the third arithmetic processing circuit 126. Then, a signal corresponding to the tilt of the first vibrator in the B direction is added, and a signal corresponding to the tilt of the first vibrator 102 in the X-axis direction is output to the input terminal of the first servo circuit 171. Then, the first servo circuit 171 controls the output signal to the fixed electrode so that the vibration of the first vibrator 102 in the X-axis direction becomes the vibration corresponding to the input signal from the sine wave generation circuit 115. .

The second, third, and fourth arithmetic processing circuits 129,
Similarly, the second arithmetic processing circuit 229 outputs a signal corresponding to the tilt of the first vibrator 107 in the X-axis direction, and the third arithmetic processing circuit 129 outputs the second vibrator 10.
The fourth arithmetic processing circuit 131 outputs a signal corresponding to the inclination of the second vibrator 107 in the Y-axis direction. Then, the second, third, and fourth servo circuits 172, 173, and 174 also operate the first and second vibrators 102 and 107 so that the input sine wave and cosine wave correspond to the actual vibration. Control vibration.

At this time, the output signals of the first, second, third, and fourth servo circuits 171 to 174 are the difference between the excitation signal and the locus of the vibrator actually vibrating. By using the detection circuit 13 shown in the first embodiment or the second embodiment described above, the signal can be generated around the X-axis and the Y-axis.
Angular velocity around the axis and Z axis, X axis direction, Y axis direction and Z
The acceleration around the axis can be obtained respectively.

[0130] In this way, micromachining is applied.
In the third embodiment of the present invention, not only can the sensor be made small, but also it is not necessary to use two vibrators as described above, and a vibrator with high accuracy can be obtained. It is easy to make a large number, and it is also possible to average the signals detected from each transducer,
It has a unique effect that it is easy to increase accuracy.

Further, a piezoresistive effect element is used to detect the inclination of the vibrator. Since the piezoresistive effect element can be formed integrally with the spring portion, the natural frequency generated by bonding a piezoelectric element or the like is obtained. Can be reduced, and a more accurate sensor can be realized. Further, since the piezoresistive effect element can lower the impedance, a signal with less noise can be obtained.

In the sensors according to the first to third embodiments, a plurality of transducers are provided, the transducers are turned in directions opposite to each other with a predetermined phase difference, and the Coriolis force and the acceleration applied to each transducer are changed. Is detected, it is possible to obtain three-axis angular velocity and acceleration signals (not only about the X and Y axes but also about the Z axis) with high sensitivity and high S / N ratio. Become.

In the first to third embodiments, the angular velocity signals around the three axes of X, Y, and Z are obtained. For example, the high-pass filter 27 shown in FIG. With the configuration including the signal processing circuit system up to the gain adjustment circuit 42, it is possible to obtain an angular velocity signal or the like of the Z axis (detection axis in the same direction as the longitudinal direction of the transducer) with high detection accuracy. A sensor can be built. The structure of the vibrator in this case is not limited to the structure shown in FIGS. 1 and 5, and a conventionally known vibrator having both ends supported (including a non-columnar vibrator). It is also possible to use.

A sensor capable of detecting angular velocities around three axes is disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 147903/1994. And a highly accurate angular velocity signal can be obtained. Similarly, it is possible to obtain a high-accuracy signal with no influence of the angular velocity for the accelerations in the three axial directions. Further, when a sensor as disclosed in JP-A-6-147903 is to be manufactured by micromachining, a vibrator having a longitudinal direction in the thickness direction of the sensor chip must be manufactured, and the sensor chip becomes thicker. In addition, there is a problem that manufacturing is difficult, but a sensor in which such a point is improved can be provided.

(Correspondence between Invention and Embodiment) In the first to third embodiments, the first and second vibrators 2, 7
Or, 102 and 107 are the vibrator of the present invention, the first to eighth magnets 5a to 5d, 10a to 10d, the first to eighth coils 6a to 6d, 11a to 11d, and the movable electrode 105a.
To 105d, 110a to 110d, fixed electrode 106a to
The drive circuits 106d, 111a to 11d, the drive circuit 12, and the drive circuit 112 correspond to the drive unit of the present invention, and the detection circuits 13, 113 correspond to the detection unit of the present invention.

The correspondence between the components of the embodiment and the components of the present invention has been described above. However, the present invention is not limited to the configuration of the embodiment, and the functions and features described in the claims are not limited.
Needless to say, any configuration may be used as long as the functions of the embodiment can be achieved.

The planned turning surface is a surface of a turning locus of the vibrator in a state where no angular velocity and no acceleration are applied.

(Modification) In each of the above embodiments,
Each of them has been described as an example having two vibrators (vibrators). However, the present invention is not limited to this, and a sensor having two or more vibrators may be used. And
When two or more vibrators are provided, for example, when the first to fourth vibrators are provided, the inclination of the first vibrator and the third vibrator around the detection axis (or the detection axis direction). The signal obtained by adding and averaging the signals of FIG. 2 and the signal obtained by adding and averaging the signals having inclinations around the detection axis (or in the direction of the detection axis) of the second vibrator and the fourth vibrator are shown in FIG. By outputting to the signal processing circuit system of FIG. 3, it is expected that a more accurate angular velocity signal (acceleration signal) can be obtained as compared with the case where two vibrators are provided (averaging each output). By
Variations in the structure of each pair of transducers,
(Because variations in resistance can be reduced.)

[0139]

As described above, according to the present invention,
It is possible to provide a sensor capable of outputting an angular velocity signal about the turning axis of the weight portion with high detection accuracy.

According to the present invention, the detection accuracy is high.
It is possible to provide a sensor capable of outputting an acceleration signal in the direction of the turning axis of the weight portion.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a sensor according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a sensor driving circuit and a signal detection unit according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a detection circuit of the sensor according to the first embodiment of the present invention.

FIG. 4 is a block diagram illustrating a configuration of a detection circuit of a sensor according to a second embodiment of the present invention.

FIG. 5 is a perspective view showing a configuration of a sensor according to a third embodiment of the present invention.

FIG. 6 is a block diagram illustrating a configuration of a detection circuit of a sensor according to a third embodiment of the present invention.

[Description of Signs] 2 First vibrator 3 First vibration base 4a to 4d Piezoelectric element 5a to 5d Magnet 6a to 6d Coil 7 Second vibrator 9a to 9d Piezoelectric element 10a to 10d Magnet 11a to 11d Coil 12 Drive circuit 13 detection circuit 14 oscillation circuit 15 cos wave generation circuit 17 sine wave generation circuit 27 to 30, 55, 58 first to sixth high-pass filters 31 to 34 first to fourth one-period averaging circuits 35 to 37, 43 first to fourth adder circuits 38 offset circuits 40, 50 to 53, 62 first to sixth differential amplifier circuits 39, 42, 45 first to third gain adjustment circuits 41, 46 to 49 first To fifth signal processing circuit 44, 56, 59, 63 first to fourth low-pass filters 45, 54, 57 first to third variable gain adjustment circuits 60, 61 first, first The average circuit 107 first vibrator 110a~110d movable electrode 150a~150d movable electrode

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Susumu Sugiyama 4006 Black Stone, Shimada, Tenpaku-cho, Tenpaku-ku, Nagoya City, Aichi Prefecture

Claims (5)

[Claims] 1. A plurality of weights, a support means for cantilevering the plurality of weights in the same direction, a driving force applied to the support means, and at least one of the plurality of weights is first
And a driving means for turning the remaining weights in a second direction opposite to the first direction, and turning the weights in the first direction by the driving means. The difference between the spread of the trajectory and the spread of the turning trajectory of the weight portion turning in the second direction is calculated, and the driving means excludes the acceleration component in the turning axis direction of the scheduled turning surface for turning the weight portion. A sensor for detecting an angular velocity around an axis. 2. The method according to claim 1, wherein the detecting unit is configured to determine a turning trajectory of the weight unit that turns in the first direction with respect to the planned turning surface on an axis parallel to the planned turning surface on which the driving unit turns the weight unit. 2. The sensor according to claim 1, wherein an angular velocity component about a turning axis of the predetermined turning surface is subtracted from a difference between a shift and a shift of a turning trajectory of the weight portion turning in the second direction. 3. 3. A plurality of weights, support means for cantilevering the plurality of weights in the same direction, and a driving force applied to the support means, so that at least one of the plurality of weights is first.
Driving means for turning the remaining weight portion in a second direction opposite to the first direction, and turning the weight portion in the first direction by the driving means. The sum of the spread of the trajectory and the spread of the turning trajectory of the weight portion turning in the second direction is calculated, and the driving means removes the angular velocity component about the turning axis of the scheduled turning surface for turning the weight portion. A sensor comprising: detecting means for detecting acceleration in an axial direction. 4. The turning trajectory of the weight portion that turns in the first direction with respect to the planned turning surface on an axis parallel to the planned turning surface on which the driving device turns the weight portion. 4. The sensor according to claim 3, wherein an acceleration component of the predetermined turning surface in a turning axis direction is subtracted from a sum of a shift and a shift of a turning trajectory of the weight portion turning in the second direction. 5. The weighting unit according to claim 1, wherein the detecting unit detects a shift of a turning locus of the weight portion turning in the first direction and a shift of a turning locus of the weight portion turning in the second direction. 5. The sensor according to claim 1, wherein the value is obtained as a value corresponding to an average value during one cycle of the turning motion.