JP2011141197A - Linear position sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem that a conventional linear position sensor needs a complicated structure and becomes less reliable. <P>SOLUTION: In the linear position sensor, first to third scale members 21-23 are arranged so that a combination of a width of a gap 24 in a first scale and a width of a gap 25 in a second scale at a first position 26 along a scale direction 3 differs from a combination of the width of the gap 24 in the first scale and the width of the gap 25 in the second scale at a second position 27 along the scale direction 3. An arithmetic part 31 is structured to detect a relative position of a detection stator 1 and a scale body 2 along the scale direction 3 based on a signal 15a from a first detection coil 15 and a signal 16a from a second detection coil 16. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a linear position sensor, and in particular, the combination of the width of the first in-scale gap and the width of the second in-scale gap at the first position along the scale direction is the second position at the second position along the scale direction. By configuring the first to third scale members so as to be different from the combination of the width of the gap in one scale and the width of the gap in the second scale, the gap between the detection stator and the scale body is wide. The present invention relates to a new improvement that can be applied to a wide range of applications.

  As this type of linear position sensor that has been conventionally used, for example, a configuration described in Patent Document 1 below can be given. In the sensor having such a configuration, a change in the gap length between the detection stator and the scale body is used as a position detection signal.

JP 2000-314606 A

  In the conventional linear position sensor as described above, a change in the gap length between the detection stator and the scale body is used as a position detection signal. Therefore, if the gap between the detection stator and the scale body is widened, the gap length is increased. The position detection signal due to the change of becomes small. For this reason, the gap between the detection stator and the scale body cannot be widened, which causes a limitation of the application target.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a linear position sensor that can widen the gap between the detection stator and the scale body and widen the application range. It is.

  A linear position sensor according to the present invention is a linear position sensor in which a detection stator and a scale body are arranged to face each other via a gap, and a relative position along the scale direction between the detection stator and the scale body is detected. The stator core provided in the detection stator and the second provided in the stator core so as to be spaced apart from each other so that the first protrusion is positioned along a width direction orthogonal to the scale direction. And a third protrusion, an excitation coil wound around the first protrusion, a first detection coil wound around the second protrusion, and a second detection wound around the third protrusion. A first scale member, a first scale member, a first scale member, a first scale member, and a first scale member disposed on the scale body and spaced apart from each other along the width direction so as to face the first to third protrusions; Members and said A first in-scale gap provided between two scale members, a second in-scale gap provided between the first scale member and the third scale member, and the first and second detection coils. The first to third scale members are a combination of the width of the first scale gap and the width of the second scale gap at the first position along the scale direction. Is different from the combination of the width of the gap in the first scale and the width of the gap in the second scale at the second position along the scale direction, and the arithmetic unit is configured to detect the first detection Based on a signal from the coil and a signal from the second detection coil, a relative position between the detection stator and the scale body along the scale direction is detected.

  The first to third scale members may be configured such that one of the first and second scale gaps becomes narrower and the other becomes wider as it goes from one end of the scale body along the scale direction to the other end. Is provided.

  The first and second offset adjustment coils wound around the first protrusion may be further provided, and the calculation unit may be configured to obtain a difference between a signal from the first detection coil and a signal from the first offset adjustment coil. And a relative position between the detection stator and the scale body along the scale direction is detected based on a difference between the signal from the second detection coil and the signal from the second offset adjustment coil.

A first bobbin around which the excitation coil, the first offset adjustment coil, and the second offset adjustment coil are wound; a second bobbin around which the first detection coil is wound; and the second detection coil. A third bobbin around which the excitation coil, the first offset adjustment coil, the second offset adjustment coil, the first detection coil, and the second detection coil are the first to first coils. By inserting the three bobbins into the first to third protrusions, the three bobbins are wound around the first to third protrusions via the first to third bobbins.
The exciting coil, the first offset adjusting coil, and the second offset adjusting coil are wound around the first bobbin so as to overlap each other along the radial direction of the first bobbin.
In addition, the first bobbin is provided separately from each other, and is disposed so as to overlap each other along the longitudinal direction of the first protrusion, and the first adjustment coil bobbin portion, 2 adjustment coil bobbins, and the excitation coil, the first offset adjustment coil, and the second offset adjustment coil are the excitation coil bobbin, the first adjustment coil bobbin, and the By being wound around the bobbin portion for the second adjustment coil, they are stacked and disposed along the longitudinal direction.
In addition, the first bobbin is provided integrally with each other, and is disposed so as to overlap with each other along the longitudinal direction of the first protrusion. The bobbin portion for excitation coil, the bobbin portion for first adjustment coil, and the second An adjustment coil bobbin portion, and the excitation coil, the first offset adjustment coil, and the second offset adjustment coil include the excitation coil bobbin portion, the first adjustment coil bobbin portion, and the first adjustment coil bobbin portion; By being wound around the bobbin part for 2 adjustment coils, it is laminated and disposed along the longitudinal direction.
The first bobbin includes an excitation coil bobbin portion and an adjustment coil bobbin portion that are provided integrally with each other and are disposed to overlap each other along the longitudinal direction of the first protrusion. The exciting coil is wound around the exciting coil bobbin portion, and the first and second offset adjusting coils are overlapped with each other along the radial direction of the adjusting coil bobbin portion. It is wound around.

The excitation bobbin further includes a first bobbin around which the excitation coil is wound, a second bobbin around which the first detection coil is wound, and a third bobbin around which the second detection coil is wound. The coil, the first detection coil, and the second detection coil are configured such that the first to third bobbins are inserted into the first to third protrusions, and the first to third bobbins are inserted through the first to third bobbins. It is wound around the first to third protrusions.
Moreover, the said 1st-3rd scale member is created by laminating | stacking the thin plate which consists of a steel plate, a silicon steel plate, or a permalloy along the said scale direction.

  According to the linear position sensor of the present invention, the combination of the width of the first in-scale gap and the width of the second in-scale gap at the first position along the scale direction is the first at the second position along the scale direction. Since the first to third scale members are arranged to be different from the combination of the width of the gap in the scale and the width of the gap in the second scale, the signal from the first detection coil and the signal from the second detection coil are used. Based on this, the relative position between the detection stator and the scale body along the scale direction can be detected. That is, since the relative position between the detection stator and the scale body can be detected regardless of the gap between the detection stator and the scale body, the gap between the detection stator and the scale body can be widened and the application range can be widened. .

It is a perspective view which shows the linear position sensor by Embodiment 1 of this invention. It is sectional drawing of the stator core of FIG. It is a perspective view which shows the 1st and 2nd in-scale gap of FIG. It is sectional drawing of the principal part of the linear position sensor by Embodiment 2 of this invention. It is sectional drawing of the principal part of the linear position sensor by Embodiment 3 of this invention. It is sectional drawing of the principal part of the linear position sensor by Embodiment 4 of this invention. It is sectional drawing of the principal part of the linear position sensor by Embodiment 5 of this invention.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
1 is a perspective view showing a linear position sensor according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view of the stator core of FIG. 1, and FIG. 3 shows first and second in-scale gaps of FIG. It is a perspective view. In FIG. 1, the linear position sensor is provided with a detection stator 1 and a scale body 2 that are arranged to face each other with a gap 5 therebetween. The detection stator 1 and the scale body 2 are provided so as to be relatively displaceable along the scale direction 3. That is, a detected body (not shown) that needs to detect linear displacement is connected to one of the detection stator 1 and the scale body 2, and one connected to the detected body is connected to the other. Are configured to be displaced.

  The detection stator 1 has a stator core 10 (E-type core) formed by laminating a plurality of E-shaped magnetic plate members (silicon steel plates). The stator core 10 may be made of permalloy or a dust core. The stator core 10 is provided with first to third protrusions 11 to 13, and the first protrusion 11 is arranged at the center position of the stator core 10 along the width direction 4 orthogonal to the scale direction 3. And the 3rd protrusions 12 and 13 are arrange | positioned mutually spaced apart so that the 1st protrusion 11 may be located along the width direction 4. FIG. That is, the second and third protrusions 12 and 13 are arranged separately on both sides of the first protrusion 11.

  An excitation coil 14 is wound around the first protrusion 11, a first detection coil 15 is wound around the second protrusion 12, and a second detection coil 16 is wound around the third protrusion 13. . Specifically, as shown in FIG. 2, the excitation coil 14, the first detection coil 15, and the second detection coil 16 have the first to third protrusions 11 through the first to third bobbins 110 to 130. It is wound around ~ 13. The 1st-3rd bobbins 110-130 are inserted in the 1st-3rd protrusions 11-13 in the state by which each coil 14-16 was wound beforehand.

  Returning to FIG. 1, the scale body 2 is provided with first to third scale members 21 to 23 made of a magnetic plate member extending along the scale direction 3. If it demonstrates in detail, the 1st-3rd scale members 21-23 will be produced by laminating | stacking the thin plate which consists of a steel plate, a silicon steel plate, or a permalloy along the scale direction 3. FIG. The first to third scale members 21 to 23 are arranged apart from each other along the width direction 4 so as to face the first to third protrusions 11 to 13 respectively. Specifically, the first scale member 21 is disposed so as to face the first protrusion 11, and the second and third scale members 22, 23 face the second and third protrusions 12, 13, respectively. The first scale member 21 is disposed on the side of the first scale member 21.

  A first in-scale gap 24 is formed between the first scale member 21 and the second scale member 22, and a second in-scale gap 25 is formed between the first scale member 21 and the third scale member 23. Is formed. In this embodiment, the first and second in-scale gaps 24 and 25 are air gaps.

  As shown in FIG. 3, the first to third scale members 21 to 23 have a width of the first scale gap 24 and a second scale gap 25 at the first position 26 (arbitrary position) along the scale direction 3. The combination with the width is provided to be different from the combination of the width of the first scale gap 24 and the second scale gap 25 at the second position 27 (another arbitrary position) along the scale direction 3. Yes. Specifically, the first to third scale members 21 to 23 are either one of the first and second in-scale gaps 24 and 25 as they go from the one end 2a of the scale body 2 along the scale direction 3 to the other end 2b. They are arranged such that (the first in-scale gap 24) becomes narrower and the other (the second in-scale gap 25) becomes wider.

  Returning to FIG. 1, an excitation circuit 30 is connected to the excitation coil 14, and a calculation unit 31 is connected to the first and second detection coils 15 and 16. The excitation circuit 30 inputs an excitation current 30 a to the excitation coil 14 and generates a magnetic flux from the excitation coil 14. The magnetic flux from the excitation coil 14 passes through the first detection coil 15 through a magnetic path including the first scale member 21, the first in-scale gap 24, and the second scale member 22, and the first scale member 21, The second detection coil 16 passes through the magnetic path including the second scale gap 25 and the third scale member 23. In addition, since the 1st-3rd scale members 21-23 are produced by laminating | stacking the thin plate which consists of a steel plate, a silicon steel plate, or a permalloy along the scale direction 3, the magnetic flux from the exciting coil 14 is a scale. Flow along direction 3 is prevented.

  Here, the widths of the first and second in-scale gaps 24 and 25 greatly affect the magnitude of the magnetic flux passing through the first and second detection coils 15 and 16. That is, the first detection at an arbitrary position along the scale direction 3 is provided by providing the first to third scale members 21 to 23 so that the first and second in-scale gaps 24 and 25 are formed as described above. The combination of the signal 15a from the coil 15 and the signal 16a from the second detection coil 16 is configured to be different from the combination at other arbitrary positions.

  The calculation unit 31 detects the relative positions of the detection stator 1 and the scale body 2 along the scale direction 3 based on the signal 15 a from the first detection coil 15 and the signal 16 a from the second detection coil 16. . Specifically, when the voltage value of the signal 15a from the first detection coil 15 is Va and the voltage value of the signal 16a from the second detection coil 16 is Vb, the calculation unit 31 calculates (Va−Vb) / By calculating the ratio of (Va + Vb), the relative position between the detection stator 1 and the scale body 2 is detected.

  In such a linear position sensor, the combination of the width of the first in-scale gap 24 and the width of the second in-scale gap 25 at the first position 26 along the scale direction 3 is the second position 27 along the scale direction 3. Since the first to third scale members 21 to 23 are arranged so as to be different from the combination of the width of the first in-scale gap 24 and the width of the second in-scale gap 25, the signal from the first detection coil 15 Based on 15a and the signal 16a from the second detection coil 16, the relative position of the detection stator 1 and the scale body 2 along the scale direction 3 can be detected. That is, since the relative position between the detection stator 1 and the scale body 2 can be detected regardless of the gap 5 between the detection stator 1 and the scale body 2, the gap between the detection stator and the scale body can be widened. The application range can be widened. Further, the number of coils can be reduced and the configuration of the scale body 2 can be simplified as compared with the conventional gap length variation type or the toothed scale type.

  Further, as one of the first and second in-scale gaps 24 and 25 becomes narrower and the other becomes wider as it goes from one end 2a of the scale body 2 along the scale direction 3 to the other end 2b, the first to third thirds. Since the scale members 21 to 23 are arranged, the combination of the widths of the first and second in-scale gaps 24 and 25 can be made to differ more reliably, and the reliability can be improved more reliably. In addition, the total value of the signals 15a and 16a from the first and second detection coils 15 and 16 can be made constant regardless of the relative positions of the detection stator 1 and the scale body 2, and strong resistance can be obtained due to the fluctuation of the gap 5. Obtainable.

  Further, the excitation coil 14, the first detection coil 15, and the second detection coil 16 are configured such that the first to third bobbins 110 to 130 are inserted into the first to third protrusions 11 to 13, thereby Since the first to third protrusions 11 to 13 are wound around the third bobbins 110 to 130, the bobbins 110 to 130 on which the coils 14 to 16 are wound in advance are connected to the protrusions 11 to 13. The coil 14-16 can be completely wound around the protrusions 11-13, and the manufacturing process can be simplified.

  Furthermore, since the 1st-3rd scale members 21-23 are produced by laminating | stacking the thin plate which consists of a steel plate, a silicon steel plate, or a permalloy along the scale direction 3, the magnetic flux from the exciting coil 14 is produced. The flow along the scale direction 3 can be prevented, and the relative position detection accuracy between the detection stator 1 and the scale body 2 can be improved.

Embodiment 2. FIG.
FIG. 4 is a cross-sectional view of a main part of the linear position sensor according to the second embodiment of the present invention. In the first embodiment, the configuration in which only the exciting coil 14 is wound around the first protrusion 11 has been described. However, in the configuration of the second embodiment, as shown in FIG. The excitation coil 14, the first offset adjustment coil 17, and the second offset adjustment coil 18 are wound around the first protrusion 11 via the first bobbin 110. Specifically, the exciting coil 14 is directly wound around the first bobbin 110, and the first offset adjusting coil 17 is wound around the exciting coil 14 along the radial direction 110a of the first bobbin 110, thereby being second offset. The adjustment coil 18 is wound around the first offset adjustment coil 17 along the radial direction 110a. The first and second offset adjusting coils 17 and 18 detect a constant electromotive force generated by the magnetic flux from the exciting coil 14 regardless of variations in the widths of the first and second in-scale gaps 24 and 25. .

  The calculation unit 31 obtains a difference (referred to as a first difference) between the signal 15a from the first detection coil 15 and the signal 17a from the first offset adjustment coil 17. This first difference is a value that directly indicates the width of the first in-scale gap 24 at the relative position between the detection stator 1 and the scale body 2 when the first difference is obtained. Similarly, the calculation unit 31 obtains a difference (referred to as a second difference) between the signal 15a from the first detection coil 15 and the signal 17a from the second offset adjustment coil 17. The second difference is a value that directly indicates the width of the second in-scale gap 25 at the relative position between the detection stator 1 and the scale body 2 at the time when the second difference is obtained.

  In addition, the calculation unit 31 amplifies the first difference and the second difference described above, and based on the first difference and the second difference, the relative relationship between the detection stator 1 and the scale body 2 along the scale direction 3. The correct position. Specifically, the voltage values of the signals 15a and 16a from the first and second detection coils 15 and 16 are Va and Vb, and the voltage values of the signals 17a and 18a from the first and second offset adjustment coils 17 and 18 are set. , Vo1 and Vo2, the computing unit 31 obtains the first difference as Va ′ = Va−Vo1 and the second difference as Vb ′ = Vb−Vo2, and (Va′−Vb ′) / (Va The relative position between the detection stator 1 and the scale body 2 is detected by calculating the ratio of “+ Vb”). By subtracting Vo1 and Vo2 from Va and Vb as described above, the ratio (Va'-Vb ') / (Va' + Vb ') can be increased, and the relative position detection accuracy can be improved. Other configurations are the same as those in the first embodiment.

  In such a linear position sensor, the calculation unit 31 includes the difference between the signal 15a from the first detection coil 15 and the signal 17a from the first offset adjustment coil 17, and the signal 16a from the second detection coil 16 and the second signal. Since the relative position of the detection stator 1 and the scale body 2 along the scale direction 3 is detected based on the difference from the signal 18a from the offset adjustment coil 18, the relative relationship between the detection stator 1 and the scale body 2 is detected. It is possible to more reliably obtain a signal change due to the variation in the widths of the first and second in-scale gaps 24 and 25 due to the displacement, thereby further improving the reliability.

  In addition, the exciting coil 14, the first offset adjusting coil 17, the second offset adjusting coil 18, the first detecting coil 15, and the second detecting coil 16 are configured such that the first to third bobbins 110 to 130 have the first to third protrusions. Since the coils 11 to 13 are inserted into the first to third protrusions 11 to 13 via the first to third bobbins 110 to 130, the coils 14 to 18 are wound in advance. Further, by inserting the bobbins 110 to 130 into the protrusions 11 to 13, the winding of the coils 14 to 18 on the protrusions 11 to 13 can be completed, and the manufacturing process can be simplified.

  Further, the exciting coil 14, the first offset adjusting coil 17, and the second offset adjusting coil 18 are wound around the first bobbin 110 so as to overlap each other along the radial direction 110a of the first bobbin 110. The shape of one bobbin 110 can be simplified, and the manufacturing cost can be reduced.

Embodiment 3 FIG.
FIG. 5 is a cross-sectional view of a main part of the linear position sensor according to the third embodiment of the present invention. In the second embodiment, the excitation coil 14, the first offset adjustment coil 17, and the second offset adjustment coil 18 have been described so as to overlap each other along the radial direction 110a. In the linear position sensor, the exciting coil 14, the first offset adjusting coil 17, and the second offset adjusting coil 18 are stacked and disposed along the longitudinal direction 11 a of the first protrusion 11.

  More specifically, the first bobbin 110 of the third embodiment is provided with an exciting coil bobbin portion 111, a first adjustment coil bobbin portion 112, and a second adjustment coil bobbin portion 113. The exciting coil bobbin portion 111, the first adjusting coil bobbin portion 112, and the second adjusting coil bobbin portion 113 are provided separately from each other and overlap each other along the longitudinal direction 11a of the first protrusion. Are arranged. The exciting coil 14, the first offset adjusting coil 17, and the second offset adjusting coil 18 are provided separately from the exciting coil bobbin portion 111, the first adjusting coil bobbin portion 112, and the second adjusting coil. By being wound around the bobbin portion 113, the layers are stacked in the longitudinal direction 11a. Other configurations are the same as those of the second embodiment.

  In such a linear position sensor, the exciting coil 14, the first offset adjusting coil 17, and the second offset adjusting coil 18 include the exciting coil bobbin portion 111 and the first adjusting coil bobbin provided separately from each other. Since it is wound around the portion 112 and the second adjustment coil bobbin portion 113, even if any one of the coils 14, 17, and 18 is broken during manufacturing, it corresponds to the broken coils 14, 17, and 18 Only the bobbins 111 to 113 to be replaced need to be replaced, and the cost of discarded parts can be reduced.

Embodiment 4 FIG.
FIG. 6 is a cross-sectional view of a main part of the linear position sensor according to the fourth embodiment of the present invention. In the third embodiment, the configuration in which the excitation coil bobbin portion 111, the first adjustment coil bobbin portion 112, and the second adjustment coil bobbin portion 113 are provided separately from each other has been described. As shown in FIG. The exciting coil bobbin portion 111, the first adjusting coil bobbin portion 112, and the second adjusting coil bobbin portion 113 may be provided separately from each other. Other configurations are the same as those of the third embodiment.

  In such a linear position sensor, the exciting coil 14, the first offset adjusting coil 17, and the second offset adjusting coil 18 are formed of an exciting coil bobbin portion 111, a first adjusting coil bobbin portion 112, And since it winds around the bobbin part 113 for 2nd adjustment coils, the number of parts to manage can be reduced and management cost can be reduced.

Embodiment 5 FIG.
FIG. 7 is a cross-sectional view of a main part of the linear position sensor according to the fifth embodiment of the present invention. In the third and fourth embodiments, the configuration in which the first offset adjusting coil 17 and the second offset adjusting coil 18 are stacked in the longitudinal direction 11a has been described. However, as shown in FIG. The coil 17 and the second offset adjusting coil 18 may be stacked in a direction orthogonal to the longitudinal direction 11a.

  More specifically, the first bobbin 110 of the fifth embodiment is provided with an exciting coil bobbin portion 111 and an adjustment coil bobbin portion 114. The exciting coil bobbin portion 111 and the adjustment coil bobbin portion 114 are provided integrally with each other, and are disposed so as to overlap each other along the longitudinal direction 11a of the first protrusion. The exciting coil 14 is wound around the exciting coil bobbin portion 111, and the first offset adjusting coil 17 and the second offset adjusting coil 18 are overlapped with each other along the radial direction 114a of the adjusting coil bobbin portion 114. It is wound around the bobbin portion 114. Other configurations are the same as those in the third and fourth embodiments.

  In such a linear position sensor, the exciting coil 14 is wound around the exciting coil bobbin portion 111, and the first offset adjusting coil 17 and the second offset adjusting coil 18 are arranged along the radial direction 114 a of the adjusting coil bobbin portion 114. Therefore, the shape of the first bobbin 110 can be simplified and the manufacturing cost can be reduced compared to the configurations of the third and fourth embodiments.

DESCRIPTION OF SYMBOLS 1 Detection stator 2 Scale body 3 Scale direction 5 Gap 10 Stator core 11-13 1st-3rd protrusion 14 Excitation coil 15,16 1st and 2nd detection coil 17,18 1st and 2nd offset adjustment coil 21-23 First to third scale members 24, 25 First and second in-scale gaps 31 Calculation unit 110 First bobbin 111 Excitation coil bobbin portion 112, 113 First and second adjustment coil bobbin portion 114 Adjustment coil bobbin portion 120 2nd bobbin 130 3rd bobbin

Claims (10)

The detection stator (1) and the scale body (2) are arranged to face each other with a gap (5) therebetween, and the detection stator (1) and the scale body (2) are relatively aligned along the scale direction (3). A linear position sensor for detecting a position,
A stator core (10) provided on the detection stator (1);
A first protrusion (11) provided on the stator core (10);
Second and second portions provided on the stator core (10) so as to be spaced apart from each other along the width direction (4) perpendicular to the scale direction (3). 3 protrusions (12, 13);
An exciting coil (14) wound around the first protrusion (11);
A first detection coil (15) wound around the second protrusion (12);
A second detection coil (16) wound around the third protrusion (13);
1st-3rd provided in the said scale body (2) and mutually spaced apart along the said width direction (4) so that it may each oppose to the said 1st-3rd protrusion (11-13). A scale member (21-23);
A first in-scale gap (24) provided between the first scale member (21) and the second scale member (22);
A second in-scale gap (25) provided between the first scale member (21) and the third scale member (23);
A calculation unit (31) connected to the first and second detection coils (15, 16),
The first to third scale members (21 to 23) have a width of the first scale gap (24) at the first position (26) along the scale direction (3) and the second scale gap ( 25) is a combination of the width of the first scale gap (24) and the second scale gap (25) at the second position (27) along the scale direction (3). It is provided differently from the combination,
The computing unit (31) follows the scale direction (3) based on the signal (15a) from the first detection coil (15) and the signal (16a) from the second detection coil (16). A linear position sensor for detecting a relative position between the detection stator (1) and the scale body (2).   The first to third scale members (21 to 23) are arranged such that the first and second scales move from one end (2a) to the other end (2b) of the scale body (2) along the scale direction (3). The linear position sensor according to claim 1, wherein one of the inner gaps (24, 25) is provided so as to be narrow and the other is widened. The first and second offset adjustment coils (17, 18) wound around the first protrusion (11),
The calculation unit (31) includes a difference between a signal (15a) from the first detection coil (15) and a signal (17a) from the first offset adjustment coil (17), and the second detection coil (16). ) And the scale body (2) based on the difference between the signal (16a) from the second offset adjustment coil (18) and the scale direction (3). 3. The linear position sensor according to claim 1, wherein the relative position is detected. A first bobbin (110) around which the excitation coil (14), the first offset adjustment coil (17), and the second offset adjustment coil (18) are wound;
A second bobbin (120) around which the first detection coil (15) is wound;
A third bobbin (130) around which the second detection coil (16) is wound;
The excitation coil (14), the first offset adjustment coil (17), the second offset adjustment coil (18), the first detection coil (15), and the second detection coil (16) The third bobbin (110 to 130) is inserted into the first to third protrusions (11 to 13), so that the first to third bobbins (110 to 130) are inserted through the first to third bobbins (110 to 130). The linear position sensor according to claim 3, wherein the linear position sensor is wound around three protrusions (11 to 13).   The exciting coil (14), the first offset adjusting coil (17), and the second offset adjusting coil (18) are overlapped with each other along the radial direction of the first bobbin (110). The linear position sensor according to claim 4, wherein the linear position sensor is wound around. The first bobbin (110) is provided separately from each other, and the bobbin portion for exciting coil (111) disposed so as to overlap each other along the longitudinal direction (11a) of the first protrusion (11), A first adjusting coil bobbin portion (112) and a second adjusting coil bobbin portion (113);
The exciting coil (14), the first offset adjusting coil (17), and the second offset adjusting coil (18) include the exciting coil bobbin portion (111) and the first adjusting coil bobbin portion (112). 5. The linear position sensor according to claim 4, wherein the linear position sensor is laminated along the longitudinal direction (11 a) by being wound around the bobbin portion (113) for the second adjustment coil. The first bobbin (110) is provided integrally with each other, and the exciting coil bobbin portion (111) disposed in a manner overlapping the longitudinal direction (11a) of the first protrusion (11), A first adjusting coil bobbin portion (112) and a second adjusting coil bobbin portion (113);
The exciting coil (14), the first offset adjusting coil (17), and the second offset adjusting coil (18) include the exciting coil bobbin portion (111) and the first adjusting coil bobbin portion (112). 5. The linear position sensor according to claim 4, wherein the linear position sensor is laminated along the longitudinal direction (11 a) by being wound around the bobbin portion (113) for the second adjustment coil. The first bobbin (110) and the exciting coil bobbin portion (111) arranged integrally with each other along the longitudinal direction (11a) of the first protrusion (11) are adjusted. A coil bobbin portion (114), and
The exciting coil (14) is wound around the exciting coil bobbin portion (111),
The first and second offset adjusting coils (17, 18) are overlapped with each other along the radial direction (114a) of the adjusting coil bobbin portion (114) and wound around the adjusting coil bobbin portion (114). The linear position sensor according to claim 4, wherein the linear position sensor is provided. A first bobbin (110) around which the exciting coil (14) is wound;
A second bobbin (120) around which the first detection coil (15) is wound;
A third bobbin (130) around which the second detection coil (16) is wound;
In the excitation coil (14), the first detection coil (15), and the second detection coil (16), the first to third bobbins (110 to 130) are connected to the first to third protrusions (11). To 13), and is wound around the first to third protrusions (11 to 13) via the first to third bobbins (110 to 130). The linear position sensor according to claim 1 or 2.   The said 1st-3rd scale member (21-23) is produced by laminating | stacking the thin plate which consists of a steel plate, a silicon steel plate, or a permalloy along the said scale direction. The linear position sensor according to claim 9.

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