JP2002357621A - Accelerometer with orthogonal axis error correcting function and orthogonal axis error correcting method for accelerometer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an accelerometer with an orthogonal axis error correcting function capable of electrically correcting an orthogonal axis sensitivity error and provide an orthogonal axis error correcting method for the accelerometer. SOLUTION: This accelerometer with the orthogonal axis error correcting function is provided with a pendulum 1 cantilever supported on a pair of yokes 2A and 2B via a flexure 3, an arc-sectional first coil 10 provided in a first region 11 and generating an electromagnetic force for returning the displacement of the pendulum 1 to zero by coacting with a magnet 5, a pair of arc-sectional second coils 13A and 13B provided in a second region 12 and generating an electromagnetic force for correcting the orthogonal axis sensitivity error, and a detector 7 detecting the displacement of the pendulum 1 based on the output of the first coil 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an accelerometer having an orthogonal axis error correction function and an orthogonal axis error correction method for an accelerometer, and more particularly to a method of electrically correcting an orthogonal axis error of a pendulum to change or reproduce a zero point. New improvement for reducing deterioration of sex.

[0002]

2. Description of the Related Art An example of this type of apparatus conventionally used is an accelerometer as shown in FIG. That is, in FIGS. 5A and 5B, a pendulum indicated by reference numeral 1 is a pendulum provided in a case 9 via a flexure 3 in a pair of cylindrical yokes 2A and 2B. The pendulum 1 moves as a pendulum about the flexure 3 as a center of rotation.

The pendulum 1 is provided with a moving coil 4 (see FIG. 6) which is wound around the input shaft of the accelerometer in a circular shape. The moving coil 4 is fixed to the yokes 2A, 2B. The moving coil 4 and the magnet 5 constitute a torquer 6 of an accelerometer corresponding to the magnet 5 provided. The torquer 6 is connected to a detector 7, and the output of the detector 7 is input to the moving coil 4 via a detection circuit system 8 including a servo amplifier and the like. A signal output from the coil 4 is extracted as an acceleration signal corresponding to the acceleration of the pendulum 1.

[0004]

Since the conventional apparatus is configured as described above, there are the following problems. That is, an error (hereinafter, referred to as an orthogonal axis error) occurs in the orthogonal axis 1a due to a processing error, an assembly error, or the like of the components such as the pendulum 1 and the yoke 2, and the orthogonal axis error is corrected by an adjustment screw (not shown). Has been adjusted by humans, and there has been a problem that accuracy problems arise.

Further, the moving coil 4 generates an electromagnetic force for returning the displacement of the pendulum 1 to zero in response to the movement of the pendulum 1, but the moving coil 4 of the moving coil 4 which is farther from the pendulum support portion 1A. The portion 4A generates an effective electromagnetic force for returning the pendulum 1 to zero, but the coil portion 4B of the moving coil 4 which is closer to the support 1A of the pendulum 1 has a support 1A serving as a fulcrum of the pendulum 1. Since the distance from the pendulum 1 is short, this portion has not contributed much from the viewpoint of generating an electromagnetic force for returning the displacement of the pendulum 1 to zero.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. In particular, a moving coil is divided into a portion near a pendulum support portion and a portion far from the pendulum support portion, and the moving coil is supported with a perpendicular axis interposed therebetween. The present invention provides an accelerometer with a quadrature axis error correction function for correcting a quadrature axis sensitivity error generated by a mechanical error by dividing a moving coil on the side close to a part into two, and a quadrature axis error correction method for the accelerometer. Aim.

[0007]

An accelerometer with an orthogonal axis error correcting function according to the present invention comprises a pair of cylindrical yokes and a pendulum supported in a cantilever manner between the pair of yokes via a flexure. A magnet fixed in the recess of the yoke, and a first magnet remote from the support of the pendulum of the yoke.
A first coil having an arcuate cross section that is provided in the area and generates an electromagnetic force for returning the displacement of the pendulum to zero in cooperation with the magnet, and a second area close to the support of the pendulum of the yoke A pair of second coils having an arc-shaped cross section for generating an electromagnetic force for correcting an orthogonal axis sensitivity error of the pendulum, and detecting a displacement of the pendulum based on an output of the first coil. Wherein the second coil is disposed so as to sandwich the tilting center axis of the pendulum, and the first coil is configured to have a semicircular cross section. The second coil has a configuration in which a center line radially passing through the center of the arc-shaped cross section is disposed at an elevation angle of 45 degrees with respect to an end plane of the first region. Is a configuration having a quarter-circumferential cross section. Also, the orthogonal axis error correction method for an accelerometer according to the present invention is an accelerometer for measuring an acceleration applied to the pendulum by detecting a displacement of a pendulum supported in a cantilever manner between a pair of cylindrical yokes. In the orthogonal axis error correction method, the orthogonal axis of the pendulum is formed by a pair of correction coils having an arc-shaped cross section provided so as to sandwich the tilting center axis of the pendulum on the side of the yoke near the support portion of the pendulum. The correction coil has a configuration in which a center line radially penetrating the center of the arc-shaped cross-section has an elevation angle of 45 ° with respect to an end plane in a region of the yoke far from the support portion of the pendulum. It is a configuration that is arranged so as to be accurate.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an accelerometer with orthogonal axis error correction function and an orthogonal axis error correction method for an accelerometer according to the present invention will be described below in detail with reference to the drawings. The same or equivalent parts as those of the conventional device are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 1, an accelerometer with an orthogonal axis error correction function according to the present invention comprises a pair of cylindrical yokes 2A, 2A,
The pendulum 1 is supported on the case 9 via the flexure 3 in a cantilever manner between B. A first coil 10 and second coils 13A and 13B are wound around the pendulum 1.
The first coil 10 includes a pair of yokes 2A and 2B,
a, the supporting portion 1 of the pendulum 1 in the space formed by
It is wound around the pendulum 1 so as to fit in a semi-cylindrical first region 11 farther from A. As shown in FIGS. 2 and 3, the first coil 10 is configured to have a semicircular cross section, and extends in a direction penetrating the plane of FIG.

A pair of second coils 13A and 13B functioning as correction coils, which will be described later, are provided in the support 1A of the pendulum 1 in the space formed by the recesses 2a and 2b of the pair of yokes 2A and 2B, respectively. The semi-cylindrical second on the near side
It is wound around the pendulum 1 so as to fit within the area 12. The second coils 13A and 13B are configured to have a quarter-circumferential cross section, and extend in a direction penetrating the paper surface in FIG. Further, the second coils 13A and 13B
Is a center line 13a radially passing through the center of the arc-shaped cross section,
13b is disposed so as to form an elevation angle of 45 degrees with respect to the end plane 11A of the first region 11. The first coil 10 and the second coils 13A and 13B are naturally insulated from each other.

As shown in the circuit diagram of FIG. 4, the first coil 10 is connected to a detector 7 of a type for detecting a change in capacitance, and the output of the detector 7 is connected to a servo amplifier or the like. It is configured to be input to the first coil 10 via a detection system circuit 8 including the same. The signal output from the first coil 10 is taken out as an acceleration signal corresponding to the acceleration of the pendulum 1. Also, the second coil 13A,
13B is connected to a power supply 15 for supplying a reference voltage via current adjusting means 14A and 14B.

Therefore, according to the accelerometer with the orthogonal axis error correcting function of the present invention, the orthogonal axis error caused by the processing error or the assembly error of the pendulum 1 and the yokes 2A and 2B is measured at the time of assembling the accelerometer. If the variable resistors of the current adjusting means 14A and 14B are adjusted in accordance with the following equation, an electromagnetic force is always applied to the pendulum 1 from one of the second coils 13A or 13B functioning as a correction coil. An accelerometer with corrected errors can be provided.

In the above description, the first coil 10 has a semicircular cross section (a fan angle of 180 °) and the second coils 13A, 13A
A case has been described in which B forms a quarter-circle cross section (sector angle of 90 °). However, if the function as an accelerometer can be maintained, the sector angle of the first coil in the cross-sectional shape is more than 180 °. A large or small arc-shaped cross section may be used, and the second coils 13A, 13B
May be changed. In the above description, the first coil 10 and the second coils 13A, 13A
Although the case where the interval between B is extremely narrow has been described, the interval between these coils may be further increased.

[0014]

According to the present invention, there is provided an accelerometer with an orthogonal axis error correcting function, comprising: a pair of cylindrical yokes; and a pendulum supported in a cantilever manner between the pair of yokes via a flexure.
A magnet fixed in the recess of the yoke and an electromagnetic force provided in a first area of the yoke far from the support of the pendulum and cooperating with the magnet to return the displacement of the pendulum to zero. A first coil having an arc-shaped cross section and a yoke having an arc-shaped cross section which is provided in a second region of the yoke near a support portion of the pendulum and generates an electromagnetic force for correcting an orthogonal axis sensitivity error of the pendulum. A pair of second coils, and a detector that detects displacement of the pendulum based on an output of the first coil, and the second coil is disposed so as to sandwich the tilting center axis of the pendulum. By adjusting the current flowing through the second coil, it is possible to provide an accelerometer with a quadrature axis error correction function capable of electrically correcting the quadrature axis error of the pendulum. Further, since the first coil has a semicircular cross section, it is possible to provide an accelerometer with an orthogonal axis error correction function that can easily improve the assembly accuracy and, as a result, can easily correct the orthogonal axis error. Further, the second coil is disposed such that a center line radially passing through the center of the arc-shaped cross section forms an elevation angle of 45 degrees with respect to the end plane of the first region, so that it is easy to improve assembly accuracy. As a result, it is possible to provide an accelerometer with an orthogonal axis error correction function that can easily correct the orthogonal axis error. Further, since the second coil has a configuration having a quarter-circumferential cross section, it is possible to provide an accelerometer with a quadrature axis error correction function that can easily improve assembling accuracy, and as a result, can easily correct a quadrature axis error. . Also, the orthogonal axis error correction method for an accelerometer according to the present invention is an accelerometer for measuring an acceleration applied to the pendulum by detecting a displacement of a pendulum supported in a cantilever manner between a pair of cylindrical yokes. In the orthogonal axis error correction method, the orthogonal axis of the pendulum is formed by a pair of correction coils having an arc-shaped cross section provided so as to sandwich the tilting center axis of the pendulum on the side of the yoke near the support portion of the pendulum. Since the sensitivity error is corrected, the orthogonal axis error of the accelerometer can be accurately corrected. Further, the correction coil is disposed such that a center line radially passing through the center of the arc-shaped cross section forms an elevation angle of 45 degrees with respect to an end plane in a region of the yoke that is far from the support of the pendulum. Therefore, it is easy to improve the assembly accuracy, and as a result, it is easy to correct the orthogonal axis error.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing an accelerometer with an orthogonal axis error correction function according to the present invention.

FIG. 2 is a configuration diagram schematically showing a main part of an accelerometer with an orthogonal axis error correction function according to the present invention.

FIG. 3 is a cross-sectional view schematically showing a configuration of an accelerometer with an orthogonal axis error correction function according to the present invention.

FIG. 4 is a diagram schematically showing a circuit configuration of an accelerometer with an orthogonal axis error correction function according to the present invention.

FIG. 5 is a cross-sectional view schematically showing a configuration of a conventional accelerometer.

FIG. 6 is a configuration diagram schematically showing a conventional accelerometer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pendulum 1A Support part 1a Orthogonal axis 2A, 2B Yoke 2a Depression 3 Flexure 5 Magnet 7 Detector 8 Detection system circuit 9 Case 10 1st coil 11 1st area 11A End plane 12 2nd area 13A, 13B 2nd coil 13a, 13b Center line 14A, 14B Current adjusting means

Claims (6)

[Claims] A pair of cylindrical yokes (2A, 2B) and a pendulum (1) supported in a cantilever manner between the pair of yokes (2A, 2B) via a flexure (3), A magnet (5) fixed in a recess (2A) of the yoke (2A, 2B);
A, 2B) of the first area (1) far from the support (1A) of the pendulum (1)
1) a first coil (10) having an arcuate cross section for generating an electromagnetic force for returning the displacement of the pendulum (1) to zero in cooperation with the magnet (5), and the yoke ( 2A, 2B)
A pair of arc-shaped cross sections that are provided in a second area (12) near the support portion (1A) of the pendulum (1) and generate an electromagnetic force for correcting an orthogonal axis sensitivity error of the pendulum (1). Based on the outputs of the second coils (13A, 13B) and the first coil (10),
A detector (7) for detecting a displacement of the pendulum (1), wherein the second coil (13A, 13B) includes a tilting center axis of the pendulum (1).
An accelerometer with a quadrature axis error correction function, which is disposed so as to sandwich (1D). 2. The accelerometer according to claim 1, wherein the first coil has a semicircular cross section. 3. The second coil (13A, 13B) has a center line (13a, 13b) radially passing through the center of the arc-shaped cross section of the second coil (13A, 13B).
3. The accelerometer according to claim 1, wherein the accelerometer is provided so as to form an elevation angle of 45 degrees with respect to an end plane (11A) of the region (11). 4. The accelerometer with an orthogonal axis error correction function according to claim 1, wherein said second coil (13A, 13B) has a quarter circle shape in cross section. 5. An acceleration for measuring an acceleration applied to the pendulum (1) by detecting a displacement of the pendulum (1) supported in a cantilever manner between a pair of cylindrical yokes (2A, 2B). In the orthogonal axis error correction method, the yoke (2A, 2B)
The area side (12) near the support part (1A) of the pendulum (1) in
Correcting the orthogonal axis sensitivity error of the pendulum (1) by a pair of correction coils (13A, 13B) having an arc-shaped cross section provided so as to sandwich the tilting center axis (1D) of the pendulum (1). A method for correcting an orthogonal axis error of an accelerometer, comprising: 6. The correction coil (13A, 13B) has a center line (13a, 13b) radially passing through the center of the arc-shaped cross section of the correction coil (13A, 13B) supporting the pendulum (1) in the yoke (2A, 2B). 6. The method according to claim 5, wherein the vertical axis is disposed at an angle of elevation of 45 degrees with respect to an end plane of the area away from the section.