JP2009204541A - Capacitance type sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capacitance type sensor for lowering cross-axis sensitivity only by adjusting the sensitivity of an X-axis and a Y-axis even when the balance of beam members is not completely achieved due to variations in manufacturing. <P>SOLUTION: The capacitance type sensor includes displaceable weights 42a-42e; a holding member 41 for holding the weights 42a-42e via the beam members 43da, 43ab, 43bc, and 43cd; and detection electrodes 32a and 32b for the X-axis and detection electrodes 32c and 32d for the Y-axis opposed to the weights 42a-42e to detect changes in the electrostatic capacitance between the weights 42a-42e and the electrodes 32a to 32d. The electrodes 32a-32d are opposed to the weights 42a-42d. A plurality of the electrodes 32a-32d opposed to the weights to computes the difference between the sum of outputs of adjacent electrodes 32a and 32b among the plurality of electrodes and the sum of outputs obtained from the remaining adjacent electrodes 32c and 32d. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a capacitive sensor, and more specifically, includes a displaceable weight body and a plurality of electrodes arranged to face the weight body, and the weight body and a plurality of electrodes. The present invention relates to a capacitance type sensor that detects a change in capacitance.

  As a conventional capacitive sensor, there is a sensor that detects Coriolis force acting on a vibrator based on a change in capacitance of a capacitive element. For example, in the device described in Patent Document 1, a flexible disc-shaped displacement substrate and a rigid fixed substrate are opposed to each other and supported by an apparatus housing, and the displacement substrate and the fixed substrate are opposed to each other. An electrode is provided on the vibrator and the vibrator is fixed to the displacement substrate. An AC drive signal is given between the opposing electrodes, and the vibrator is vibrated up and down using Coulomb force. The first capacitor element and the second capacitor element are configured by the opposing electrodes, and when the angular velocity is applied, the displacement substrate is tilted by the Coriolis force + Fx, and the change in the capacitance between the vibrator and the electrode is detected. is there.

  Moreover, what is described in Patent Document 2 is a capacitive sensor having a structure in which four beam members are provided orthogonally to a weight body constituting an intermediate substrate.

  FIG. 1 is a configuration diagram of an intermediate substrate of a conventional capacitive sensor, which is described in FIG. The weight body 215 has a structure including four wing-like portions when viewed from above. The flexible portion 225 includes a plate-like frame body that surrounds the weight body 215 and four beam portions BM separated by the slit SL. The slit SL forms a through groove that separates the weight body 215 and the flexible portion 225. As described above, when the weight body 215 is physically separated by the slit SL, the weight body 215 is supported only by the four beam portions BM, so that the weight body 215 is further displaced. A structure that is easy to do

  That is, in this Patent Document 2, four beam members are provided orthogonally, and the detection electrode is inclined by 45 ° with respect to the beam member (between two adjacent beam members). A capacitive sensor is disclosed.

  The Coriolis force applied to the weight body supported by the four beam members is detected as the displacement of the weight body, and the detection method of the displacement of the weight body is a detection arranged facing the weight body. A change in capacitance between the electrode and the weight body is detected.

  In the capacitance type sensor having such a structure, when detecting the Coriolis force from the difference in capacitance change by using the two detection electrodes provided on the respective axes in the X-axis and Y-axis directions, It is assumed that the beam members are balanced.

JP-A-10-227644 JP 2007-46927 A

  However, in Patent Document 2 described above, when the balance of the beam members is out of order, the direction of the Coriolis force applied to the weight body does not coincide with the direction of displacement of the weight body, and the acceleration sensor detects the displacement as a capacitance. However, there is a problem that the direction of the Coriolis force is errored and the direction of the Coriolis force cannot be accurately detected.

  In addition, the shape of the beam member and the weight body that affect the balance has manufacturing variations in terms of processing accuracy, and not all angular velocity sensors are balanced. This imbalance of balance appears as a poor sensitivity of other axes, which is an important characteristic of the angular velocity sensor.

  The angular velocity sensor having such a structure has a drawback that the sensitivity of the other axis appears sensitively when the balance of the beam members is out of order due to manufacturing variations.

  The present invention has been made in view of such problems, and the object of the present invention is only to adjust the sensitivity of the X-axis and the Y-axis even when the beam members are not perfectly balanced due to manufacturing variations. An object of the present invention is to provide a capacitive sensor that can reduce the sensitivity of other axes.

  The present invention has been made to achieve such an object, and the invention according to claim 1 includes a displaceable weight body (42a to 42d) and a beam member (43da to 43cd). A holding member (41) for holding the weight body, and a plurality of electrodes (32a to 32d) arranged to face the weight body, wherein the plurality of electrodes (32a to 32d) A sum of outputs from the adjacent electrodes ((32a and 32b) or (32d and 32a)) among the plurality of electrodes ((A + B) or (D + A)), and the remaining The difference ([(A + B) − (C + D)] or [([(C + D)] or the sum ((C + D) or (B + C))) obtained from the adjacent electrodes ((32c and 32d) or (32b and 32c)) D + A) − (B + C)]) and calculating the angular velocity of each axis component A signal calculating unit (FIGS. 5 and 6) is provided for detecting a change in capacitance between the weight body and the plurality of electrodes.

  The invention according to claim 2 is the invention according to claim 1, wherein the weight body has a center portion (42e) arranged at an intersection of the beam members, and the holding member and the beam It has the peripheral part (42a-42d) arrange | positioned from the said center part to the clover type along the member, It is characterized by the above-mentioned.

  The invention according to claim 3 is the invention according to claim 2, wherein the beam member is adjacent to the weight body along a diagonal line of the holding member from a central portion of the weight body. It is arranged so as to be sandwiched between peripheral portions.

  According to a fourth aspect of the invention, in the invention of the second or third aspect, the shape of the electrode is similar to the peripheral portion of the weight body arranged in the crowbar shape. It is characterized by that.

  According to a fifth aspect of the present invention, in the first aspect of the invention, the signal calculation unit is configured to output the output signal from the first electrode (32a) among the plurality of electrodes as A and second electrodes. When the output signal from (32b) is B, the output signal from the third electrode (32c) is C, and the output signal from the fourth electrode (32d) is D, the output signal from the first electrode A first adder (201) for adding A and the output signal B of the second electrode, and adding the output signal C from the third electrode and the output signal D of the fourth electrode And an output signal (A + B) − (C + D) from a first operational amplifier (406) that calculates the difference between the output signals of the first and second adders. With the angular velocity of the axial component, the output signal D from the fourth electrode and the output signal A from the first electrode are added. A third adder (203), and a fourth adder (204) for adding the output signal B from the second electrode and the output signal C from the third electrode, And the output signal (D + A) − (B + C) from the second operational amplifier (407) for calculating the difference between the output signals of the fourth adder is used as the angular velocity of the Y-axis component. (Fig. 5)

  According to a sixth aspect of the present invention, in the first aspect of the present invention, the signal computation unit outputs an output signal from the first electrode (32a) among the plurality of electrodes as A and second electrodes. When the output signal from (32b) is B, the output signal from the third electrode (32c) is C, and the output signal from the fourth electrode (32d) is D, the output signal from the first electrode A first operational amplifier (411) for calculating a difference between an output signal C between A and the third electrode; an output signal B from the second electrode; and an output signal D from the fourth electrode A second operational amplifier (412) for calculating a difference; and an adder (200) for adding the output signals of the first and second operational amplifiers. An output signal (A + B) − ( C + D) is the angular velocity of the X-axis component, and the output signal A from the first electrode and the second electric power are A third operational amplifier (413) for calculating the difference between the output signal B and the fourth operation for calculating the difference between the output signal C from the third electrode and the output signal D from the fourth electrode. An amplifier (414) and a fifth operational amplifier (408) for calculating a difference between the output signals of the first and second operational amplifiers, and an output signal (D + A)-(B + C) from the fifth operational amplifier ) Is the angular velocity of the Y-axis component. (Fig. 6)

  The invention according to claim 7 has a sandwich structure in which another plurality of electrodes are arranged to face the plurality of electrodes and sandwich the weight body in the invention according to claim 1. It is characterized by that.

  The invention according to claim 8 is the invention according to claim 7, wherein the shape of the plurality of other electrodes is similar to the periphery of the weight body arranged in a clover shape. It is characterized by that.

  According to the present invention, the movable body includes a displaceable weight body, a holding member that holds the weight body via the beam member, and a plurality of electrodes that are disposed to face the weight body, The angular velocity of the axial component is calculated by calculating the difference between the sum of the outputs from the adjacent electrodes of the plurality of electrodes and the sum of the outputs obtained from the remaining adjacent electrodes. Capacitance type sensor that can reduce the sensitivity of other axes only by adjusting the sensitivity of the X and Y axes even if the beam members are not perfectly balanced due to manufacturing variations. Can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
In order to clarify the characteristics of the capacitive sensor according to the present invention, first, a comparative example will be described below.

  FIG. 2 is a configuration diagram for explaining a comparative example with the capacitive sensor according to the present invention. The capacitance type sensor of this comparative example includes a holding member 21 that holds displaceable weight bodies 22a to 22e, and a detection electrode 12a provided on the substrate 11 so as to face the weight bodies 22a to 22e. Thru | or 12d, and it is comprised so that the change of the electrostatic capacitance between the weight bodies 22a thru | or 22d and the detection electrodes 12a thru | or 12d may be detected.

  The weight bodies 22a to 22e are held by the holding member 21 via the beam members 23da, 23ab, 23bc, and 23cd. The detection electrodes 12a to 12d provided on the substrate 11 are provided with X-axis detection electrodes 12a and 12c and Y-axis detection electrodes 12b and 12d arranged to face the weights 22a to 22d. . Reference numeral 13 denotes a drive electrode disposed at the center of the X-axis detection electrodes 12a and 12c and the Y-axis detection electrodes 12b and 12d.

  Further, the detection electrodes 12a to 12d are arranged to face the weight bodies 22a to 22d without covering directly above the beam members 23da to 23cd.

  The beam member 23da is sandwiched between the weight body 22d and the weight body 22a, the beam member 23ab is sandwiched between the weight body 22a and the weight body 22b, and the beam member 23bc is sandwiched between the weight body 22b and the weight body 22b. The beam member 23cd is a beam member sandwiched between the weight body 22c and the weight body 22d.

  The weight bodies 22a to 22e have a center portion 22e disposed at the intersections of the beam members 23da to 23cd, and are disposed in a clover shape from the center portion 22e along the holding member 21 and the beam members 23da to 23cd. Peripheral portions 22a to 22d are provided.

  Further, the beam members 23da to 23cd are arranged so as to be sandwiched between adjacent peripheral portions 22a to 22d of the weight body along the diagonal line of the holding member 21 from the center portion 22e of the weight body. The electrodes 12a to 12d have a shape similar to that of the peripheral portions 22a to 22d of the weight body arranged in a crowbar shape extending in four directions from the center.

  In such a configuration, the output signal from the X-axis detection electrode 12a is A, the output signal from the X-axis detection electrode 12b is B, the output signal from the Y-axis detection electrode 12c is C, and the Y-axis detection electrode Assuming that the output signal from 12d is D, as shown in FIG. 4A, the angular velocity component in the X-axis direction is detected as X = A−B, and the angular velocity component in the Y-axis direction is detected as Y = D−C. The detection direction in this case has an inclination of 45 ° with respect to the beam members 23da to 23cd. That is, the axis constituted by the beam members 23da and 23bc, the axis constituted by the beam members 23ab and 23cd are the axis constituted by the X-axis detection electrodes 12a and 12c, and the Y-axis detection electrodes 12b and 12d. Each has an inclination of 45 ° with the axis of construction.

  As shown in FIG. 7A, the characteristics of the capacity change and the angular velocity due to the configuration in this comparative example are obtained when the angular velocity is given around the Y axis by rotating the Y axis, and the X axis direction and the Y axis Although the output that appears in the direction is plotted while changing the magnitude of the angular velocity, if the angular velocity is about the Y axis with respect to vibration in the Z-axis direction, only the X-axis output should appear as the Coriolis force, Y-axis output is obtained. The Y-axis output that does not appear originally at the angular velocity around the Y-axis corresponds to 35% of the desired X-axis output, that is, the other-axis sensitivity is 35%. Here, the diamond shape in the figure indicates the angular velocity component in the X-axis direction, and the rectangle indicates the angular velocity component in the Y-axis direction.

FIG. 3 is a configuration diagram for explaining an embodiment of the capacitance type sensor according to the present invention.
The capacitive sensor of the present invention includes a holding member 41 that holds displaceable weight bodies 42a to 42e and a plurality of detection electrodes provided on the substrate 31 so as to face the weight bodies 42a to 42e. 32a to 32d, and configured to detect a change in capacitance between the weight bodies 42a to 42d and the detection electrodes 32a to 32d.

  The weight bodies 42a to 42e are held by the holding member 41 via the beam members 43da, 43ab, 43bc, 43cd. The plurality of detection electrodes 32a to 32d provided on the substrate 31 are the first and second detection electrodes 32a and 32b arranged to face the weight bodies 42a to 42d, and the third and fourth detection electrodes. 32c and 32d. Reference numeral 33 denotes a drive electrode disposed in the central portion of the first and second detection electrodes 32a and 32b and the third and fourth detection electrodes 32c and 32d.

  The plurality of electrodes 32a to 32d are arranged to face the weight body, and are obtained from the sum of outputs from the adjacent electrodes 32a and 32b and the remaining adjacent electrodes 32c and 32d among the plurality of electrodes. A signal calculation unit (FIG. 5 to be described later) that calculates the difference from the sum of the outputs and calculates the acceleration of the axis component is provided.

  The beam member 43da is sandwiched between the weight body 42d and the weight body 42a, the beam member 43ab is sandwiched between the weight body 42a and the weight body 42b, and the beam member 43bc is sandwiched between the weight body 42b and the weight body 42b. The beam member 43cd is a beam member sandwiched between the weight body 42c and the weight body 42d.

  Further, the weight bodies 42a to 42e have a center part 42e arranged at the intersections of the beam members 43da to 43cd, and are arranged in a clover shape from the center part 42e along the holding member 41 and the beam members 43da to 43cd. Peripheral portions 42a to 42d are provided.

  The beam members 43da to 43cd are arranged so as to be sandwiched between adjacent peripheral portions 42a to 42d of the weight body along the diagonal line of the holding member 41 from the center portion 42e of the weight body.

  In addition, the shape of the electrode is optimally similar to the periphery of the weight body arranged in the clover type, but if it is arranged directly above the periphery of the weight body, these shapes It is not limited to.

  In such a configuration, if the output signals from the first and second detection electrodes 32a and 32b are A and B, and the output signals from the third and fourth detection electrodes 32c and 32d are C and D, FIG. As shown in (b), the angular velocity component of the X-axis is the sum of outputs A + B from the adjacent electrodes 32a and 32b and the outputs obtained from the remaining adjacent electrodes 32c and 32d among the plurality of electrodes. The difference (A + B) − (C + D) from C + D is calculated, and the Y-axis angular velocity component is the sum D + A of the outputs from the adjacent electrodes 32d and 32a among the plurality of electrodes, and the remaining adjacent electrodes 32b and 32c. The difference (D + A) − (B + C) from the sum B + C of the outputs obtained from is calculated, and the angular velocity of each axis component is calculated. The detection direction in this case has the same direction with respect to the beam members 43da to 43cd. That is, the axis constituted by the beam members 43ab and 43cd coincides with the X axis, and the axis constituted by the beam members 43da and 43bc coincides with the axis.

  FIG. 5 is a circuit diagram of a signal calculation unit according to the capacitance type sensor of the present invention. This signal calculation unit includes a sum of outputs from adjacent electrodes 32a and 32b among a plurality of electrodes and the remaining adjacent ones. The difference between the output obtained from the electrodes 32c and 32d to be calculated is calculated, and the angular velocity of each axis component is calculated.

  In the figure, C1 indicates a capacitive element constituted by the first electrode 32a and the weight body 42a, C2 indicates a capacitive element constituted by the second electrode 32b and the weight body 42b, and C3 Indicates a capacitive element configured by the third electrode 32c and the weight body 42c, and C4 indicates a capacitive element configured by the fourth electrode 32d and the weight body 42d.

  As described above, the output signal from the first electrode 32a is A, the output signal from the second electrode 32b is B, the output signal from the third electrode 32c is C, and the output signal from the fourth electrode 32d is If D, the output signal from the capacitive element C1 is obtained V1 via the C / V conversion circuit 401, and the output signal from the capacitive element C2 is obtained V2 via the C / V conversion circuit 402, The output A + B = V1 + V2 of the adder 201 is obtained. An output signal from the capacitive element C3 is obtained as V3 via the C / V conversion circuit 403, and an output signal from the capacitive element C4 is obtained as V4 via the C / V conversion circuit 404, and an adder 201 outputs C + D = V3 + V4 are obtained. Taking these differences, the output (A + B) − (C + D) = (V1 + V2) − (V3 + V4) of the operational amplifier 406 is obtained. This becomes an angular velocity component in the X-axis direction.

  An output signal from the capacitive element C4 is obtained as V4 via the C / V conversion circuit 404, and an output signal from the capacitive element C1 is obtained as V1 via the C / V conversion circuit 401, and an adder An output 203 of D + A = V4 + V1 is obtained. An output signal from the capacitive element C2 is obtained as V2 via the C / V conversion circuit 402, and an output signal from the capacitive element C3 is obtained as V3 via the C / V conversion circuit 403. 204 outputs B + C = V2 + V3 are obtained. Taking these differences, the output (D + A) − (B + C) = (V4 + V1) − (V2 + V3) of the operational amplifier 407 is obtained. This becomes an angular velocity component in the Y-axis direction.

  In FIG. 5, when X and Y are the directions of the conventional axes, X 'and Y' are axial directions rotated by 45 degrees. Like the signal calculation unit shown in FIG. 5, the axis rotates 45 degrees by the addition process and the subtraction process, so that it can be returned to X and Y by the addition process and the subtraction process of X ′ and Y ′.

  FIG. 6 is a circuit diagram of another signal calculation unit according to the capacitive sensor of the present invention. This signal calculation unit includes electrodes 32a and 32c facing each other with respect to the X-axis component among a plurality of electrodes. The difference between the outputs from 32b and 32d is added, and the difference between the outputs from the adjacent electrodes 32a and 32b and the electrodes 32c and 32d is further calculated for the Y-axis component. As a result, the same as in FIG. The angular velocity of each axis component can be calculated.

  As described above, the output signal from the first electrode 32a is A, the output signal from the second electrode 32b is B, the output signal from the third electrode 32c is C, and the output signal from the fourth electrode 32d is When D, the output signal from the capacitive element C1 is obtained through the C / V conversion circuit 401, V1 is obtained, and the output signal from the capacitive element C3 is obtained through the C / V conversion circuit 403, and V3 is obtained. The operational amplifier 411 obtains the difference V1-V3, and the output signal from the capacitive element C2 is obtained via the C / V conversion circuit 402, and the output signal from the capacitive element C4 is C / V V4 is obtained through the conversion circuit 404, the difference V2-V4 is obtained by the operational amplifier 412, and the output (V1 + V2)-(V3 + V4) of the adder 200 is obtained. This becomes an angular velocity component in the X-axis direction.

  An output signal from the capacitive element C1 is obtained as V1 via the C / V conversion circuit 401, and an output signal from the capacitive element C2 is obtained as V2 via the C / V conversion circuit 402, and an operational amplifier The difference V1-V2 is obtained by 413, the output signal from the capacitive element C3 is obtained via the C / V conversion circuit 403, and the output signal from the capacitive element C4 is obtained by the C / V conversion circuit. V4 is obtained via 404, and the difference V3-V4 is obtained by the operational amplifier 414. Taking these differences, the output (V4 + V1) − (V2 + V3) of the operational amplifier 408 is obtained. This becomes an angular velocity component in the Y-axis direction.

  In the signal calculation unit shown in FIG. 6, the differential amplifiers 411 to 414 are fully differential, and are therefore resistant to common mode noise. Further, a new axis in which X and Y are inclined by 45 ° can be set by addition or subtraction by the differential amplifiers 411 to 414, so that the axis can be freely selected.

  As shown in FIG. 7B, the characteristics of the capacity change and the angular velocity according to the configuration of the present invention are obtained when the angular velocity is given around the Y ′ axis by rotating the Y ′ axis, and in the X ′ axis direction. The output from the amplifier that appears in the Y′-axis direction is plotted while changing the magnitude of the angular velocity. Originally, only the X ′ axis output obtained from the angular velocity around the Y ′ axis appears, and the Y ′ axis output, which is an unnecessary signal, is 1% or less of the X ′ axis output. That is, the other-axis sensitivity is 1% or less. In the comparative example and the present invention, the sensor structure including the weight body and the beam member necessary for detecting the Coriolis force is the same, but the sensitivity of the other axis is greatly reduced by the present invention. I understand. Here, the diamond shape in the figure indicates the angular velocity component in the X′-axis direction, and the rectangle in the figure indicates the angular velocity component in the Y′-axis direction.

  As described above, in a conventional capacitive sensor having a beam member provided on a diagonal line, an electrode for detecting a change in capacitance detects a displacement at a position shifted by 45 ° from the beam member. For this reason, when the balance of the beam member collapses due to manufacturing variations, the direction of the Coriolis force could not be accurately detected because the beam member is displaced in a direction different from the direction in which the Coriolis force was actually applied. Since the capacitive sensor of the present invention includes the signal calculation unit, it is possible to provide a multi-axis capacitive sensor that does not generate other-axis sensitivity.

  Further, the signal calculation unit is an arithmetic circuit that uses a difference between the sum of adjacent electrodes and the sum of other adjacent electrodes. As a result, the Coriolis force applied to each axis can be accurately calculated even when the beam member is out of balance.

  In the present invention, there are two signal calculation units for obtaining the difference between the sum of the adjacent electrodes and the sum of the remaining electrodes, which may be two in the case of four electrodes, and the two axes of the X axis and the Y axis are provided. Coriolis force in the direction can be detected.

  Also, because the beam member is out of balance, the X axis. When there is a sensitivity difference between the two Y axes, an angular velocity sensor that does not generate any other axis sensitivity can be provided by aligning the sensitivity of the two axes by signal processing. That is, the signal calculation unit described above can provide a multi-axis capacitive sensor that does not generate other-axis sensitivity even if the diagonal beam members are out of balance.

  In the above-described embodiment, the case where one electrode is arranged opposite to the weight body has been described. However, the sandwich structure in which another electrode is arranged so as to sandwich the weight body opposite to the electrode. It may be. The shape of the other electrode in this case is optimally similar to the periphery of the weight body arranged in the clover type, but if it is arranged directly under the periphery of the weight body, It is not limited to these shapes.

It is a block diagram of the intermediate board of the conventional electrostatic capacitance type sensor. It is a block diagram for demonstrating the comparative example with the electrostatic capacitance type sensor which concerns on this invention. It is a block diagram for demonstrating one Example of the electrostatic capacitance type sensor which concerns on this invention. (A), (b) is a figure which shows the detection direction of the angular velocity of a X-axis and a Y-axis, (a) is the case of a comparative example, (b) has shown the case of this invention. It is a circuit diagram of the signal calculating part which concerns on the capacitive sensor of this invention. It is a circuit diagram of the other signal calculating part which concerns on the electrostatic capacitance type sensor of this invention. (A), (b) is a figure which shows the detection sensitivity characteristic of angular velocity, (a) is the case of a comparative example, (b) has shown the case of this invention.

Explanation of symbols

12a, 12c, 32a, 32b X-axis detection electrodes 12b, 12d, 32c, 32d Y-axis detection electrodes 13, 33 Drive electrodes 21, 41 Holding members 22a to 22e, 42a to 42e Weight bodies 22e, 42e Weight bodies Center portions 22a to 22d, 42a to 42d Peripheral portions 23da to 23cd, 43da to 43cd of weight bodies Beam members 200, 201, 202, 203, 204 Adder 215 Weight body 225 Flexible portions 401, 402, 403, 404 C / V conversion circuit 406, 407, 408, 411, 412, 413, 414 operational amplifier SL slit BM beam section

Claims (8)

A displaceable weight body, a holding member that holds the weight body via a beam member, and a plurality of electrodes disposed to face the weight body,
The plurality of electrodes are disposed to face the weight body,
Among the plurality of electrodes, a difference between a sum of outputs from adjacent electrodes and a sum of outputs obtained from the remaining adjacent electrodes is calculated, and a signal calculation unit that calculates an angular velocity of each axis component is provided. A capacitance type sensor that detects a change in capacitance between the weight body and the plurality of electrodes.   The weight body has a central portion arranged at an intersection of the beam members, and a peripheral portion arranged in a clover shape from the central portion along the holding member and the beam members. The capacitive sensor according to claim 1.   The said beam member is arrange | positioned so that it may be pinched | interposed into the adjacent peripheral part of the said weight body along the diagonal of the said holding member from the center part of the said weight body. The capacitance type sensor described.   4. The capacitance type sensor according to claim 2, wherein the electrode has a shape similar to the peripheral portion of the weight body arranged in the clover type. 5. The signal calculation unit is configured such that, among the plurality of electrodes, the output signal from the first electrode is A, the output signal from the second electrode is B, the output signal from the third electrode is C, and the fourth electrode When the output signal is D,
A first adder that adds an output signal A from the first electrode and an output signal B from the second electrode; an output signal C from the third electrode; and the fourth electrode. An output signal (A + B) − (C + D) from a first operational amplifier that calculates the difference between the output signals of the first and second adders. The angular velocity of the axis component,
A third adder for adding an output signal D from the fourth electrode and an output signal A from the first electrode; an output signal B from the second electrode; and the third electrode. A fourth adder that adds the output signal C, and outputs the output signal (D + A) − (B + C) from the second operational amplifier that calculates the difference between the output signals of the third and fourth adders as Y The capacitive sensor according to claim 1, wherein the angular velocity is an axial component. The signal calculation unit is configured such that, among the plurality of electrodes, the output signal from the first electrode is A, the output signal from the second electrode is B, the output signal from the third electrode is C, and the fourth electrode When the output signal is D,
A first operational amplifier for calculating a difference between an output signal A from the first electrode and an output signal C from the third electrode; an output signal B from the second electrode; and the fourth electrode; A second operational amplifier that computes the difference between the output signal D and an adder that adds the output signals of the first and second operational amplifiers, and an output signal (A + B) − ( C + D) is the angular velocity of the X-axis component,
A third operational amplifier that calculates a difference between an output signal A from the first electrode and an output signal B from the second electrode; an output signal C from the third electrode; and a fourth electrode; A fourth operational amplifier for computing the difference between the output signals D of the first and second operational amplifiers, and a fifth operational amplifier for computing the difference between the output signals of the first and second operational amplifiers. The signal (D + A) − (B + C) is an angular velocity of a Y-axis component. The capacitive sensor according to claim 1, wherein:   The capacitive sensor according to claim 1, further comprising a sandwich structure in which a plurality of other electrodes are arranged so as to face the plurality of electrodes so as to sandwich the weight body.   8. The capacitive sensor according to claim 7, wherein the plurality of other electrodes have a shape similar to a peripheral portion of the weight body arranged in a clover shape.

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