JP4997213B2 - Resolver - Google Patents

Description

  The present invention relates to a resolver used for detecting a rotation angle of an output shaft of an automobile motor.

High-power brushless motors are used in hybrid vehicles and electric vehicles, and higher power is expected in the future. In order to control a brushless motor of a hybrid vehicle, it is necessary to accurately grasp the rotation angle of the output shaft of the motor. This is because it is necessary to accurately grasp the rotational position of the rotor in order to control energization switching to each coil of the stator.
For this reason, it is desirable that the motor is provided with a resolver to accurately detect the angle. A resolver used in a drive mechanism of an automobile is required to have high accuracy because the rotational speed of the drive mechanism is high in addition to environmental resistance. As with other in-vehicle components, the resolver is required to be downsized and cost-effective.

In order to improve the accuracy of the resolver, a method employing a skew as disclosed in Patent Document 1 can be considered.
In Patent Document 1, as a method for preventing distortion of an output sine wave from a magnetic resolver, a method of changing a pitch between a rotor core and a stator core, and a skew method in which a stator core is inclined with respect to a rotor core are conventional techniques. It is disclosed.
On the other hand, in order to reduce the size of the resolver, it is known to form a printed circuit as disclosed in Patent Document 2.
In Patent Document 2, the pattern pitches in the arrangement direction of the sheet coils to be attached to the substrate are arranged at unequal pitches, thereby preventing harmonics from being added to the magnetomotive force waveform and improving the detection accuracy.

Japanese Patent Laid-Open No. 5-31590 JP 7-2111537 A

However, Patent Document 1 and Patent Document 2 have the following problems.
If the cost reduction of a resolver is considered, it is not preferable to use a winding coil. In the manufacturing process, it is difficult to reduce the cost because a winding process is absolutely necessary.
When the winding is used, the process of winding the bobbin, the process of assembling the coil, and the like increase, and the number of parts of the resolver increases, which hinders cost reduction. Moreover, since a certain thickness is required for the coil, it is difficult to reduce the thickness.

On the other hand, if the configuration disclosed in Patent Document 2 is adopted, the sheet coil can be used to reduce the thickness. However, because the sheet coil is used, the magnetomotive force waveform has a stepped sine wave shape, and detection error is caused. Will end up.
For this reason, there is a problem that it is difficult to increase accuracy. In terms of improving detection accuracy, it is conceivable to employ the skew of Patent Document 1, but it cannot be applied as it is due to the difference in shape.

  Accordingly, an object of the present invention is to provide a thin and highly accurate resolver in order to solve such problems.

In order to achieve the above object, the resolver according to the present invention has the following characteristics.
(1) An excitation coil that receives an excitation signal and a detection coil that outputs a detection signal. The detection signal changes according to the displacement of the excitation body or a passive body provided with the detection coil, and the excitation In a resolver that detects a displacement amount of the passive body from a signal and the detection signal,
Of the excitation coil or the detection coil, the coil area of the second coil arranged adjacent to the first coil is uniform, and the phase of the second coil is shifted with respect to the first coil, The amount of phase shift between the first coil and the second coil is a half cycle of the order cycle to be erased from detection errors that occur when there is no phase shift between the first coil and the second coil. It is characterized by.

(2) In the resolver described in (1),
A sheet coil is used for at least one of the detection coil and the excitation coil.

(3) In the resolver according to (1) or (2),
The passive body is a rotationally movable body, the first coil is formed inside in the radial direction, the second coil is disposed outside the first coil, and detects the amount of rotation of the rotationally movable body. It is characterized by.

(4) In the resolver according to (1) or (2),
The passive body is a rectilinear moving body, and the moving amount of the rectilinear moving body is detected.

(5) In the resolver according to any one of (1) to (4),
The first coil and the second coil are connected to form one coil.

With the resolver according to the present invention having such characteristics, the following actions and effects can be obtained.
First, the invention described in (1) has an excitation coil to which an excitation signal is input and a detection coil to output a detection signal, and the detection signal is generated according to the displacement amount of the passive body provided with the excitation coil or the detection coil. In the resolver that detects and detects the displacement of the passive body from the excitation signal and the detection signal, the coil area of the excitation coil or the detection coil and the second coil arranged adjacent to the first coil is uniform, The phase of the second coil is shifted with respect to the first coil, the amount of phase shift between the first coil and the second coil is the same as the amount of phase shift between the first coil and the second coil, Of the detection error that occurs in the state where there is no phase shift with the second coil, the half cycle of the order cycle to be erased.

For example, in an excitation coil that outputs an excitation signal using a sheet coil, the magnetomotive force waveform generated is a stepped waveform as shown in FIG. This point is also shown in Patent Document 2. And since an electromotive force waveform becomes such a stepped waveform, it becomes a cause which produces a detection error.
However, the effect of the skew is obtained by shifting the second coil with respect to the first coil by a half cycle of the order cycle to be erased from detection errors that occur in a state where there is no phase shift between the first coil and the second coil. Apparently, the signal received by the first coil of the detection coil and the signal received by the second coil are shifted in phase by θ / 2 in electrical angle, so that the error of the θ period is canceled out. Therefore, it is possible to improve the detection accuracy of the resolver by canceling a part of the cycle error of the detection signal.

The invention described in (2) uses the sheet coil in at least one of the detection coil and the excitation coil in the resolver described in (1).
By using a sheet coil as at least one of the detection coil and the excitation coil, it is possible to reduce the thickness and cost.

The invention described in (3) is the resolver described in (1) or (2), wherein the passive body is a rotary moving body, and the first coil is an inner side in the radial direction of the excitation coil or the detection coil. The second coil is disposed outside the first coil, and detects the amount of rotation of the rotary moving body.
The detection of the rotary moving body is mainly used for detecting the position of the motor. A highly accurate and thin resolver has been desired in the past, and a thin and highly accurate resolver can be provided by the present invention.

In the invention described in (4), in the resolver described in (1) or (2), the passive body is a rectilinear moving body, and the moving amount of the rectilinear moving body is detected.
As a sensor for detecting the amount of movement of not only a rotary moving body but also a rectilinear moving body, a highly accurate and thin resolver has been conventionally desired as in the invention described in (3). According to the present invention, it is possible to provide a thin and highly accurate resolver.

The invention described in (5) is the resolver described in any one of (1) to (4), wherein the first coil and the second coil are connected to form one coil.
Although the first coil and the second coil have adjacent sides, if the same coil is used for the first coil and the second coil, currents flow in opposite directions on the adjacent sides. That is, the magnetic field cancels out in adjacent portions, so that the detection accuracy of the resolver does not change even if the first coil and the second coil are one coil. For this reason, the material used for a coil can be reduced by making the 1st coil and the 2nd coil into 1 coil, and it contributes to cost reduction.

Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
First, the configuration of the first embodiment will be described.
FIG. 1A shows a coil pattern diagram of a first excitation coil used for the excitation coil of the first embodiment. FIG. 1B shows a coil pattern diagram of the second excitation coil used for the excitation coil.
FIG. 2 shows a coil pattern diagram of the detection coil.
FIG. 3 shows a schematic cross-sectional view of the resolver.
The resolver 10 includes an excitation coil 20 and a detection coil 30. As shown in FIG. 3, the excitation coil 20 and the detection coil 30 are arranged with a gap G therebetween. The excitation coil 20 and the detection coil 30 constitute a coil by a print pattern formed on the substrate 11, respectively. The first excitation coil 12A and the second excitation coil 12B are provided on the excitation coil 20 side, and the detection coil. A detection coil pattern 13 is provided at 30. The excitation coil 20 is attached to the passive body 14, and the detection coil 30 is attached to the fixed body 15.

The first excitation coil 12A, the second excitation coil 12B, and the detection coil pattern 13 formed on the substrate 11 are configured as shown in FIGS.
The first exciting coil 12A is an exciting coil 20 having four magnetic poles and a degree of two. Therefore, two S poles and two N poles are prepared and arranged alternately. The second excitation coil 12B is formed in the same pattern so as to overlap the first excitation coil 12A with the substrate 11 interposed therebetween. The first excitation coil 12A and the second excitation coil 12B are 90 degrees out of phase in electrical angle. A sine wave current is applied to the first excitation coil 12A, and a cosine wave current is applied to the second excitation coil 12B. Hereinafter, the overlapping of the first excitation coil 12A and the second excitation coil 12B is referred to as an excitation coil pattern 12.

On the other hand, the detection coil pattern 13 is also prepared in four poles corresponding to the excitation coil pattern 12. Although FIG. 2 is schematically shown, the number of coil turns is actually increased.
FIG. 4 shows an enlarged view of the detection coil pattern shown in FIG.
As shown in FIG. 4, the shape of the detection coil pattern 13 is drawn so as to pass from the start point P1 through the relay point P2 and through the end point P3, and has a skew angle θ. The start point P1 and the relay point P2, and the relay point P2 and the end point P3 are connected by a straight line.

A line connecting the center point C and the start point P1 is a reference line L1, a line connecting the center point C and the relay point P2 is a first phase line L2, and a line connecting the center point C and the end point P3 is a second phase line. Assuming L3, the first phase line L2 is angled with respect to the reference line L1, and the second phase line L3 is angled with respect to the first phase line L2 by a half cycle θ / 2. The relay line L4 is a curve having the relay radius Z as a radius.
Here, the skew angle θ is expressed by the equation θ = 360 / N. N is the cycle error order N. The relay radius Z passing through the relay point P2 is determined by the coil inner periphery r and the coil outer periphery R shown in FIG.
The relay radius Z is represented by the formula Z ² = (R ² −r ² ) / 2.
For convenience, one of the detection coil patterns 13 divided by the relay line L4 is referred to as an inner coil S1 corresponding to the first coil and an outer coil S2 corresponding to the second coil.

FIG. 5 is a block diagram showing the position detection control of the resolver.
The resolver 10 includes a circuit unit 40 and a sensor unit 50. The circuit unit 40 includes a sine wave generator 41, a high frequency generator 42, a cosine wave generator 43, a first modulator 44, a second modulator 45, a detector 46, and a phase difference detector 47. The sensor unit 50 includes an excitation coil 20, a detection coil 30, a first rotary transformer 35, and a second rotary transformer 36.
A sine wave generator 41 for generating a 7.2 kHz sine wave is connected to the second modulator 45 as shown in FIG. A cosine wave generator 43 that generates a cosine wave of 7.2 kHz is connected to the second modulator 45.

A high frequency generator 42 that generates a 360 kHz sine wave is connected to the first modulator 44 and the second modulator 45. The sine wave generator 41 and the cosine wave generator 43 are connected to a phase difference detector 47. The detector 46 is connected to a phase difference detector 47.
The first modulator 44 is connected to the first excitation coil 20A, and the second modulator 45 is connected to the second excitation coil 20B.
The detection coil 30 is connected to a first rotary transformer 35, and the second rotary transformer 36 is connected to a detector 46.

Since the resolver 10 of 1st Embodiment is the said structure, the effect | action demonstrated below is shown.
FIG. 6 shows a graph of the magnetomotive force waveform generated in the exciting coil.
The vertical axis represents magnetic force and the horizontal axis represents electrical angle. A magnetomotive force waveform W1 generated by the exciting coil 20 is shown superimposed on the ideal waveform WS.
The sine wave generated by the sine wave generator 41 is, for example, AM balanced modulated (hereinafter abbreviated as AM modulation) by the high frequency in the first modulator 44 and transmitted to the first exciting coil 12A.
At the same time, the cosine wave generated by the cosine wave generator 43 is AM-modulated by the high frequency in the second modulator 45 and transmitted to the second exciting coil 12B.

A cosine wave that is AM-modulated at a high frequency flows through the second excitation coil 12B, and a sine wave that is AM-modulated at a high frequency flows through the first excitation coil 12A. The excitation coil pattern 12 provided on the substrate 11 cannot sufficiently generate magnetic flux. However, since AM modulation is performed at a high frequency, the excitation coil pattern 12 and the detection coil pattern 13 can generate a strong magnetic flux due to the high frequency. It becomes.
However, since the magnetomotive force waveform W1 is a stepped sine wave as shown in FIG. 6, when a signal is detected by the exciting coil 20, the state shown in FIG.

FIG. 7 shows a detection coil pattern that does not employ skew. FIG. 8 is a graph showing waveforms detected by a detection coil that does not employ skew.
The detection coil 330 that does not employ skew, that is, has no phase shift between the inner coil S <b> 1 and the outer coil S <b> 2 is a × 2 resolver like the detection coil 30. As shown in FIG. 6, four detection coil patterns are arranged in series.
When the detection coil 330 is used in the resolver 10, the waveform detected by the detection coil 330 is as shown in FIG. The vertical axis represents the magnetic force, and the horizontal axis represents the electrical angle. A detection waveform W2 detected by the detection coil 330 is shown superimposed on the ideal waveform WS.
FIG. 9 is a graph showing the relationship between the sensor error and the error order N.
The vertical axis indicates the sensor error, and the horizontal axis indicates the error periodic order.
By detecting the magnetomotive force waveform W1 output from the excitation coil 20, the detection coil 330 detects a waveform such as the detection waveform W2. Although the detection waveform W2 follows the ideal waveform WS, which is an ideal waveform, a sensor error as shown in FIG. 9 occurs.
The protruding portion is noise, which becomes a detection error in the detection coil 330.

Such an error is unavoidable when the exciting coil pattern 12 as shown in FIG. 1 is used in that the magnetomotive force waveform W1 shown in FIG. 6 is generated, but the error is corrected on the detection coil 30 side. Is possible.
A method for correcting this error is to use a detection coil 30 having a detection coil pattern 13 formed on the substrate 11 as shown in FIGS.
The magnetomotive force waveform W1 generated from the excitation coil 20 is detected by the detection coil 30. As shown in FIG. 10, the coil pattern of the detection coil pattern 13 is composed of the inner coil S1 and the outer coil S2. The error is offset by the shape.

  The areas of the inner coil S1 and the outer coil S2 are designed to be substantially the same. The same effect can be obtained even if the detection coil pattern 13 is formed by using the inner coil S1 and the outer coil S2 as two independent coils, but the adjacent sides of the inner coil S1 and the outer coil S2 have opposite current flow directions. Thus, since the inner coil S1 and the outer coil S2 have the same area, the same amount of current flows, and as a result, the effect is offset. For this reason, it is set as the shape connected as shown in FIG. 2 considering the efficiency which manufactures a coil.

FIG. 10 shows a graph of the combined coil output waveform.
The coil waveform detected by the inner coil S1 is a detection waveform W2, and the coil waveform detected by the outer coil S2 is a skew detection waveform W3. By forming the detection waveform W2 and the skew detection waveform W3, a composite waveform W4 is obtained.
The starting points of the detection waveform W2 and the skew detection waveform W3 start from a point advanced by the skew angle θ, and the resultant waveform W4 obtained therefrom is from a point advanced by θ / 2 compared to the detection waveform W2. Has started.

Here, the skew angle θ is expressed by the equation θ = 360 / N, and the order to be deleted is selected for N. For example, since the peak of order 12 stands out among the peaks shown in FIG. 9, it is assumed that this error component is canceled out. In this case, N = 12, and θ is 30 °.
That is, since the inner coil S1 and the outer coil S2 are shifted by θ / 2 corresponding to a half cycle of the skew angle θ, the detection coil 30 is designed by shifting the inner coil S1 and the outer coil S2 by an electrical angle of 15 °. Accordingly, the relay point P2 is arranged at an electrical angle of 15 ° with respect to the start point P1, and the end point P3 is displaced at an electrical angle of 15 ° with respect to the relay point P2, and the detection coil 30 is formed so as to be connected by a straight line. Therefore, the shape is as shown in FIG.
By designing the detection coil 30 in this way, the waveform of the combined waveform W4 is obtained as the output of the detection coil 30.
Note that the detection waveform W2 and the skew detection waveform W3 shown in FIG. 10 are waveforms that are virtually obtained in the resolver 10 of the first embodiment.

Since the resolver 10 of 1st Embodiment shows the said structure and effect | action, the effect demonstrated below is acquired.
First, it is possible to provide a highly accurate resolver.
The resolver 10 according to the first embodiment includes an excitation coil 20 to which an excitation signal is input and a detection coil 30 to output a detection signal, and according to the displacement amount of the passive body 14 provided with the excitation coil 20 or the detection coil 30. In the resolver 10 that detects the amount of displacement of the passive body 14 from the excitation signal and the detection signal when the detection signal changes, either the excitation coil 20 or the detection coil 30 on the inner coil S1 formed on the radially inner side and the outer side. The coil area with the formed outer coil S2 is uniform, and the phase of the outer coil S2 is shifted by a half cycle with respect to the inner coil S1.

A skew effect is produced by shifting the outer coil S2 by half the skew angle θ with respect to the inner coil S1.
Therefore, a composite waveform W4 that is a composite wave of the detection waveform W2 detected by the inner coil S1 and the skew detection waveform W3 detected by the outer coil S2 is obtained as a signal. The cycle error due to the magnetomotive force waveform W1 can be obtained by synthesizing the detection waveform W2 and the skew detection waveform W3 to obtain a combined waveform W4 that cancels the cycle error.
As a result, one of the peaks of the waveform shown in FIG. 10 is canceled. Specifically, since N = 12, it is possible to cancel the order 12 peak. That is, the magnetic flux detected by the detection coil 30 by the configuration of the detection coil 30 can obtain a composite waveform W4 that cancels out the Nth order harmonic component generated as noise, so that the angle detection accuracy in the resolver 10 can be improved. It becomes possible.

In addition, the resolver 10 can be made thin and highly accurate.
The resolver 10 according to the first embodiment uses a sheet coil for at least one of the detection coil 30 and the excitation coil 20.
By adopting a method of forming the excitation coil pattern 12 and the detection coil pattern 13 on the substrate 11, the resolver 10 can be thinned. In this case, either the exciting coil 20 or the detection coil 30 may be formed as a sheet coil, or both sides may be formed as a sheet coil as in the first embodiment. However, when the sheet coil is employed, a problem on the side of the exciting coil 20 as shown in FIG. 6 occurs, and when the magnetomotive force waveform W1 is detected by the detection coil 30, a waveform such as the detected waveform W2 is obtained.
For this reason, by providing the inner coil S1 and the outer coil S2, a skew effect is obtained and the resolver 10 is realized to be both thin and highly accurate.

Next, a second embodiment of the present invention will be described with reference to the drawings.
(Second Embodiment)
The second embodiment is substantially the same as the configuration of the resolver 10 of the first embodiment, but the detection coil pattern 13 of the detection coil 30 is different. The differences will be described below.
In FIG. 11, the coil pattern figure about the detection coil 30 of the resolver 10 of 2nd Embodiment is shown.
The detection coil pattern 13 of the detection coil 30 of the second embodiment differs from the detection coil pattern 13 of the first embodiment in the way of connecting the start point P1, the relay point P2, and the end point P3.
The detection coil pattern 13 of the second embodiment passes through the starting point P1 shown in FIG. 4, passes on the reference line L1, passes on the relay line L4 at the point where the reference line L1 and the relay line L4 intersect, and passes through the relay point. It passes through P2, passes through the first phase line L2 from the relay point P2, and is connected to the coil outer periphery R.
In this way, four detection coil patterns 13 having an outer shape are prepared, and the detection coil 30 for detecting the magnetomotive force waveform W1 from the excitation coil 20 is configured.

Since 2nd Embodiment is the said structure, the same effect | action and effect as 1st Embodiment can be acquired.
Basically, the detection coil pattern 13 of the first embodiment and the detection coil pattern 13 of the second embodiment can obtain substantially the same effect.
However, the areas of the inner coil S1 and the outer coil S2 are more uniform in the detection coil pattern 13 of the second embodiment, so that the detection accuracy of the resolver 10 can be improved.

Next, a third embodiment of the present invention will be described with reference to the drawings.
(Third embodiment)
The third embodiment is different from the first embodiment in that the resolver 10 is configured as a rotary moving body, whereas the resolver 10 is configured as a rectilinear moving body. However, the principle is the same.
In FIG. 12, the coil pattern figure about the detection coil 60 of the resolver 10 of 3rd Embodiment is shown. Moreover, the conceptual diagram about the coil pattern of the detection coil 60 is shown in FIG.
The detection coil 60 is obtained by connecting the A coil and the B coil shown in FIG. 13 as one coil. The A coil and the B coil have the same shape as the A coil and the B coil having a width W and an electrical angle of 180 °, and the B coil is formed by being shifted by a half period (θ / 2) with respect to the A coil. Has been. In FIG. 12, the first coil S1 and the second coil S2 indicated by phantom lines correspond to the A coil and the B coil shown in FIG.

When the detection coil 60 is formed by arranging the A coil and the B coil side by side in the pattern of FIG. 13, the current of the portion indicated by the arrow A1 of the A coil and the current of the portion indicated by the arrow B1 of the B coil are The magnetic field is canceled because it flows in the opposite direction. For this reason, even if the A coil and the B coil are combined, the resultant composite waveform W4 has the same result. The same can be said for the arrows A2 and B2, the arrows A3 and B3, and the arrows A4 and B4. As a result, the coil pattern depicted in FIG. 13 and the coil pattern depicted in FIG. can get.
Therefore, the apex AP1 of the A coil and the apex BP1 of the B coil were connected by a straight line, the apex AP2 of the A coil and the apex BP2 of the B coil were connected by a straight line, and the coil was formed so that the width was 2W.

By doing so, the same effect as the detection of the magnetic flux from the excitation side by the coil pattern depicted in FIG. 13 can be obtained by the coil pattern depicted in FIG. It is assumed that an actual coil is drawn with a plurality of turns.
Although not shown, the exciting coil is also linearly arranged. The coil pattern is formed with a width of 2 W, and the number of magnetic poles is 4 and the order is 2 as in the first embodiment. By using such an excitation coil and detection coil 60, a 2 × linear advance type resolver 70 can be formed.

Since the rectilinear resolver 70 of the third embodiment has the above-described configuration, the following functions and effects are achieved.
Basically, similar to the first embodiment and the second embodiment, which are embodiments of the rotary moving body, it is possible to expect a reduction in the thickness and improvement in accuracy of the linear advance type resolver 70.
The detection coil 60 has a shape in which the A coil and the B coil shown in FIG. 13 are connected in a state shifted by a half period (θ / 2), so that the magnetic flux detected by the detection coil 60 has an n-order harmonic component. Is detected as an offset signal, and as a result, it is possible to improve the angle detection accuracy in the linear resolver 70.

While the present invention has been described with reference to the embodiments, it is needless to say that the present invention is not limited to the above-described embodiments, and can be appropriately modified and applied without departing from the scope of the invention.
For example, as described above, both the excitation coil 20 and the detection coil 30 are sheet coils in the first embodiment and the second embodiment, and both the excitation coil and the detection coil 60 are sheet coils in the third embodiment. Either or both of them are not prevented from adopting a coil that is not a sheet coil. Basically, a configuration that obtains the effect of skew as a countermeasure against noise generated because the magnetomotive force waveform W1 is stepped by making the exciting coil 20 side a sheet coil is desirable from the viewpoint of thinning, Since the effect of skew can be obtained even if it is not a flat surface, it can contribute to improving the accuracy of the resolver 10.

  Further, in the first to third embodiments, the excitation coil is a combination of the first excitation coil and the second excitation coil, and one coil is used as the detection coil. That is, although the resolver has two excitations and one output, the present invention can be applied to a resolver having one excitation and two outputs.

(A) It is a coil pattern figure of the 1st excitation coil used for the excitation coil of 1st Embodiment. (B) It is a coil pattern figure of the 2nd excitation coil used for the excitation coil of 1st Embodiment. It is a coil pattern figure of a detection coil of a 1st embodiment. It is a schematic cross section of the resolver of 1st Embodiment. It is an enlarged view of the coil pattern of FIG. 2 of 1st Embodiment. It is a block diagram which shows position detection control of the resolver of 1st Embodiment. It is a graph about the magnetomotive force waveform which generate | occur | produces with an exciting coil of 1st Embodiment. This is a detection coil pattern that does not employ skew shown for explanation. It is a graph about the waveform detected with the detection coil which does not employ | adopt a skew shown for description. It is a graph about the relation between sensor error and error order N of a 1st embodiment. It is a graph about a synthetic coil output waveform of a 1st embodiment. It is a coil pattern figure about the detection coil of a resolver of 2nd Embodiment. It is a coil pattern figure about the detection coil of a resolver of 3rd Embodiment. It is a conceptual diagram about the coil pattern of a detection coil shown for description.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Resolver 11 Board | substrate 12 Excitation coil pattern 12A 1st excitation coil 12B 2nd excitation coil 13 Detection coil pattern 14 Passive body 15 Fixed body 20 Excitation coil 30 Detection coil 35 1st rotary transformer 36 2nd rotary transformer 40 Circuit part 41 Sine wave Generator 42 High-frequency generator 43 Cosine wave generator 44 First modulator 45 Second modulator 46 Detector 47 Phase difference detector 50 Sensor unit θ Skew angle

Claims (4)

An excitation coil for inputting an excitation signal and a detection coil for outputting a detection signal, and the detection signal changes in accordance with a displacement amount of the excitation coil or a passive body provided with the detection coil. In a resolver that detects a displacement amount of the passive body from a detection signal,
Of the excitation coil or the detection coil, the coil area of the second coil arranged adjacent to the first coil is uniform, and the phase of the second coil is shifted with respect to the first coil,
The amount of phase shift between the first coil and the second coil is a half cycle of the order cycle to be erased from detection errors that occur when there is no phase shift between the first coil and the second coil. A resolver characterized by. The resolver according to claim 1, wherein
A resolver using a sheet coil for at least one of the detection coil and the excitation coil. The resolver according to claim 1 or claim 2,
The passive body is a rotationally movable body,
The first coil is formed radially inside;
The second coil is disposed outside the first coil;
A resolver for detecting a rotation amount of the rotary moving body. The resolver according to claim 1 or claim 2,
A resolver, wherein the passive body is a rectilinear moving body, and a moving amount of the rectilinear moving body is detected.

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