JP6134964B2 - Inductive displacement detector - Google Patents

Description

  The present invention relates to an inductive displacement detection apparatus that detects displacement using electromagnetic coupling (magnetic flux coupling) applied to calipers, linear encoders, and the like.

  The inductive displacement detector is used for precise measurement such as linear displacement and angular displacement. A conventional inductive displacement detection device includes a scale in which plates serving as magnetic flux coupling members are arranged at a predetermined pitch, and a transmission winding and a receiver that are opposed to each other so as to be relatively movable with respect to the scale and capable of magnetic flux coupling with the plate. And a sensor head in which windings are arranged.

  In order to improve the resolution and increase the accuracy of the inductive displacement detection device, the pitch of the plate serving as the magnetic flux coupling member and the dimensions of the reception loop constituting the reception winding may be reduced. However, the reception winding has a relatively complicated shape in which a plurality of reception loops are connected along the relative movement direction of the sensor head. For this reason, the dimensions of the receiving winding cannot be reduced so much due to limitations on design rules.

  In view of this problem, a technique has been proposed in which only the pitch of the magnetic flux coupling member is divided while maintaining the dimensions of the receiving loop (Patent Document 1). However, the magnetic flux coupling member disclosed here includes the transmission winding in the reception winding, and there is a concern about the influence of crosstalk. In addition, since the pitch of the magnetic flux coupling member is made fine, there is a problem that a sufficient detection range (hereinafter referred to as “ABS range”) cannot be secured when used for detection of an absolute position (hereinafter referred to as “ABS position”). Become.

JP 2006-112815 A

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an inductive displacement detector that secures an ABS range while suppressing the influence of crosstalk.

  An inductive displacement detection device according to the present invention has a scale having a first scale track and a second scale track arranged in a second direction orthogonal to the first direction that is the measurement axis direction, and is opposed to the first scale track. A first sensor track, a second sensor track disposed opposite to the second scale track, and a sensor head movable relative to the scale in a first direction. , A first transmission member, and a first reception winding composed of a plurality of first reception loops arranged in a first direction at a pitch λ1, the second sensor track having a second transmission member, and a pitch a second receiving winding comprising a plurality of second receiving loops arranged in a first direction at λ1, wherein the first scale track comprises the first transmission member and the first reception; A plurality of first magnetic flux coupling members that can be magnetically coupled to the windings and are arranged in a first direction at a pitch λ1, and the second scale track includes the second transmission member and the second reception winding. A plurality of second magnetic fluxes coupled to the wire and arranged in the first direction at a pitch λ1 / N (N is an odd number of 3 or more) and connected to the first magnetic flux coupling member by N pieces. It has a magnetic flux coupling member.

  According to the present invention, it is possible to provide an inductive displacement detector that secures an ABS range while suppressing the influence of crosstalk.

1 is a perspective view illustrating a schematic configuration of an inductive displacement detection device according to a first embodiment. It is explanatory drawing of operation | movement of the induction type displacement detection apparatus which concerns on the same embodiment. It is explanatory drawing of operation | movement of the induction type displacement detection apparatus which concerns on the same embodiment. It is a top view of the scale and sense head of the inductive displacement detector according to the second embodiment. It is a top view of the scale and sense head of the induction type displacement detection apparatus which concerns on 3rd Embodiment.

  Hereinafter, an inductive displacement detector according to an embodiment of the present invention will be described with reference to the drawings.

[First Embodiment]
FIG. 1 is a perspective view showing a schematic configuration of an inductive displacement detector 1 according to the first embodiment.

  The inductive displacement detection device 1 includes a scale 100 and a sensor head 200 disposed so as to face the scale 100. In FIG. 1, the scale 100 shows a part in the longitudinal direction. The longitudinal direction of the scale 100 is the X direction (first direction) that is the direction of the measurement axis. The sensor head 200 is arranged to be movable in the X direction with a predetermined gap with respect to the scale 100. Note that the sensor head 200 may be fixed and the scale 100 may move. That is, the sense head 200 and the scale 100 may be disposed so as to be relatively movable in the X direction.

  The scale 100 includes an insulating substrate 101 made of glass epoxy resin. As a material of the insulating substrate 101, glass, silicon, or the like may be used. Two scale tracks 110 (first scale track) and sensor track 120 (second scale track) arranged in the Y direction orthogonal to the X direction are arranged on the surface of the insulating substrate 101 facing the sensor head 200. . A plurality of magnetic flux coupling windings 111 (an example of a first magnetic flux coupling member) having the same shape are arranged on the scale track 110 in the X direction. Similarly, a plurality of magnetic flux coupling windings 121 (an example of a second magnetic flux coupling member) having the same shape are arranged on the scale track 120 in the X direction.

  The magnetic flux coupling winding 111 is a rectangular linear conductor whose longitudinal direction is the X direction. The pitch of the magnetic flux coupling winding 111 is P1 = λ1. On the other hand, the magnetic flux coupling winding 121 is a rectangular linear conductor whose longitudinal direction is the Y direction (second direction). The pitch of the magnetic flux coupling winding 121 is P2 = λ1 / 5. Further, the five magnetic flux coupling windings 112 continuously arranged in the X direction are respectively connected to one magnetic flux coupling winding 111 by the connection portion 102. The linear conductor is made of a material having a low electrical resistance such as aluminum, copper, or gold. Further, instead of the magnetic flux coupling windings 111 and 121, a space, an insulator, and a plate that inhibits magnetic flux coupling may be periodically arranged on the metal plate in the X direction. Even in this case, similarly to the case where the magnetic flux coupling windings 111 and 121 are arranged, the periodic signal depending on the position of the sensor head 100 is obtained from the receiving windings 213 and 223 described later, so that the displacement can be detected.

  Further, a passivation film (not shown) is formed on the insulating substrate 101 of the scale 100 so as to cover the magnetic flux coupling windings 111 and 121.

  The sensor head 200 includes an insulating substrate 201 made of glass epoxy resin. The material of the insulating substrate 201 may be glass or silicon. A sensor track 210 (first sensor track) and a sensor track 220 (second sensor track) are disposed on the surface of the insulating substrate 201 facing the scale 100 at positions facing the scale tracks 110 and 120.

  The sensor track 210 is formed with a rectangular transmission winding 211 (an example of a first transmission member) whose longitudinal direction is the X direction. The transmission winding 211 can be magnetically coupled to the magnetic flux coupling winding 111. Instead of the transmission winding 211, one linear conductor may be used as the transmission member. In addition, one reception winding 213 (first reception winding) is disposed inside the transmission winding 211 of the sensor track 210. The receiving winding 213 can be magnetically coupled to the magnetic flux coupling winding 111. The reception winding 213 is constituted by a plurality of reception loops 214 arranged in the X direction on the insulating substrate 201. The reception loop 214 is a diamond-shaped linear conductor. Adjacent reception loops 214 are connected by a three-dimensional intersection to form a pair loop 215. The length of the pair loop 215 in the X direction is L1 = λ1, and the length of one reception loop 214 in the X direction is λ1 / 2.

  The sensor track 220 is formed with a rectangular transmission winding 221 (an example of a second transmission member) whose longitudinal direction is the X direction. The transmission winding 221 can be magnetically coupled to the magnetic flux coupling winding 121. Instead of the transmission winding 221, one linear conductor may be used as the transmission member. In addition, one reception winding 223 (second reception winding) is disposed inside the transmission winding 221 of the sensor track 220. The reception winding 223 can be magnetically coupled to the magnetic flux coupling winding 121. The reception winding 223 includes a plurality of reception loops 224 arranged in the X direction on the insulating substrate 201. The reception loop 224 is a hexagonal linear conductor. Adjacent reception loops 224 form a pair loop 225 by connecting at a three-dimensional intersection. The length of the pair loop 225 in the X direction is L2 = λ1, and the length of one reception loop 224 in the X direction is λ1 / 2.

  The reception windings 213 and 223 are not limited to one, but may be two or more. For example, the present embodiment is applied to two reception windings arranged with a phase shift of λ1 / 4 in the X direction and three reception windings arranged with a phase shift of λ1 / 6 in the X direction. be able to.

  Further, a passivation film (not shown) is formed on the insulating substrate 201 of the sensor track 200 so as to cover the transmission windings 211 and 221 and the reception windings 213 and 223. A terminal 212 of the transmission winding 211, a terminal 216 of the reception winding 213, a terminal 222 of the transmission winding 221, and a terminal 226 of the transmission winding 223 perform calculation and control for measuring displacement through wiring. It is connected to an IC circuit (not shown). The transmission windings 211 and 221 and the reception windings 213 and 223 are made of the same material as the magnetic flux coupling windings 111 and 121. The above is the configuration of the inductive displacement detection device 1.

Next, the operation of the inductive displacement detector 1 will be briefly described.
2 and 3 are explanatory diagrams of the operation of the inductive displacement detector 1 according to the present embodiment. FIG. 2 is a plan view of a part of the transmission winding 221, the magnetic flux coupling winding 111 and the reception winding 213 included in the inductive displacement detection device 1, and when the sensor head 200 moves relative to the scale 100. 6 shows a waveform diagram of the output signal S1 from the reception winding 213 generated in FIG. 3 is a plan view of a part of the transmission winding 211, the magnetic flux coupling winding 121, and the reception winding 223 provided in the inductive displacement detection device 1 and the relative movement of the sensor head 200 with respect to the scale 100. 6 shows a waveform diagram of the output signal S2 from the reception winding 223 that is generated at the time.

First, the generation principle of the output signal S1 will be described with reference to FIG.
When a transmission excitation signal (single-phase alternating current) is sent to the transmission winding 221, an excitation current i221 flows through the transmission winding 221 in the clockwise direction when attention is paid to a certain time. Then, an alternating magnetic flux is generated from the transmission winding 221 by the excitation current i 221 and is magnetically coupled to the magnetic flux coupling winding 121. For this reason, the induced current i111 flows through the magnetic flux coupling winding 121, the connecting portion 102, and the magnetic flux coupling winding 111 counterclockwise. As a result, an alternating magnetic flux is generated from the magnetic flux coupling winding 111 and is magnetically coupled to the receiving loop 214 of the receiving winding 213. Due to this coupling, an induced current i 214 flows in the reception loop 214. As a result, a sinusoidal output signal S1 is output from the reception winding 213 by the relative movement of the sensor head 200 with respect to the scale 100, and is sent to an IC circuit (not shown). Here, the output signal S1 has a wavelength of λ1 because the pitch of the magnetic flux coupling winding 111 is P1 = λ1.

Next, the generation principle of the output signal S2 will be described with reference to FIG.
When a transmission excitation signal (single-phase alternating current) is sent to the transmission winding 211, when attention is paid to a certain time, an excitation current i211 flows in the transmission winding 211 clockwise. An alternating magnetic flux is generated from the transmission winding 211 by the excitation current i211 and is magnetically coupled to the magnetic flux coupling winding 111. For this reason, the induced current i121 flows in the counterclockwise direction in the magnetic flux coupling winding 111, the connecting portion 102, and the magnetic flux coupling winding 121. As a result, an alternating magnetic flux is generated from the magnetic flux coupling winding 121 and coupled to the receiving loop 224 of the receiving winding 223. Due to this coupling, an induced current i 224 flows in the reception loop 224. As a result, a sinusoidal output signal S2 is output from the reception winding 223 by the relative movement of the sensor head 200 with respect to the scale 100, and is sent to an IC circuit (not shown). Here, the output signal S2 has a wavelength of λ1 / 5 because the pitch of the magnetic flux coupling winding 121 is P2 = λ1 / 5.

  The output signals S1 and S2 are detected alternately. Finally, the IC circuit that has received the output signals S1 and S2 calculates and synthesizes the spatial phase from the output signals S1 and S2. As a result, the inductive displacement detection device 1 detects the ABS position where the pitch P1 = λ1 of the reception winding 111 is the ABS range.

  As described above, according to the present embodiment, the magnetic flux coupling winding of one of the two scale tracks is formed at a fine pitch, so that the resolution and high accuracy of the inductive displacement detector can be improved. it can.

  In order to secure a wide ABS range, the phase difference between the output signals of a plurality of tracks may be taken. In this embodiment, the magnetic flux coupling windings of the other scale track are formed with a rough pitch. Therefore, the magnetic flux coupling windings of other tracks can be formed on the basis of this pitch. This makes it easy to widen the ABS range of the inductive displacement detector.

  Further, according to the present embodiment, the transmission winding for driving the magnetic flux coupling winding of the predetermined scale track and the receiving winding for receiving the induced current from the magnetic flux coupling winding are formed separately and output. Since the signals S1 and S2 are detected alternately, the influence of crosstalk can be reduced.

  In the example shown in FIGS. 1 to 3, the magnetic flux coupling windings 121 are arranged at a pitch P2 = λ1 / 5. However, the pitch of the magnetic flux coupling windings 121 is not limited to this, and P2 = λ1 / If it is N (N is an odd number of 3 or more), the effect of this embodiment can be obtained.

[Second Embodiment]
The second embodiment is a modification of the first embodiment, and is an inductive displacement detection device that is less affected by yawing.

  FIG. 4 is a plan view of a part of the scale 300 and the sense head 400 of the inductive displacement detector 2 according to the second embodiment.

  The inductive displacement detection device 2 includes a scale 300 and a sensor head 400 arranged so as to face the scale 300.

  The scale 300 includes an insulating substrate, and on the surface of the insulating substrate facing the sensor head 400, three scale tracks 310 (first scale track), a scale track 320 (second scale track) arranged in the Y direction, and A scale track 330 (third scale track) is arranged.

  In the scale track 310, a plurality of magnetic flux coupling windings 311 (an example of the first magnetic flux coupling member) having the same shape are arranged in the X direction. The magnetic flux coupling winding 311 is a rectangular linear conductor whose longitudinal direction is the X direction. A magnetic flux coupling winding 312 (an example of an antiphase magnetic flux coupling member) having a shape equivalent to that of the magnetic flux coupling winding 311 is disposed between the magnetic flux coupling windings 311. That is, the magnetic flux coupling winding 311 and the magnetic flux coupling winding 312 are alternately arranged in the X direction on the scale track 310. The magnetic flux coupling windings 311 are arranged at a pitch P1 = λ1. Further, the magnetic flux coupling winding 212 is also arranged at a pitch P1 ′ = λ1. Adjacent magnetic flux coupling windings 311 and 312 are separated by λ1 / 2.

  The scale track 320 has the same configuration as the scale track 120 in the first embodiment. Note that the five magnetic flux coupling windings 321 (the magnetic flux coupling winding 121 in the first embodiment) arranged continuously in the X direction are respectively connected to one magnetic flux coupling winding 311 and the connection portion 302. Yes.

  The scale track 330 has the same configuration as the scale track 320. However, the magnetic flux coupling winding 321 (an example of the second magnetic flux coupling member) of the scale track 320 and the magnetic flux coupling winding 331 (an example of the third magnetic flux coupling member) of the scale track 330 are phased by λ1 / 10 in the X direction. Is off. Further, the five magnetic flux coupling windings 331 continuously arranged in the X direction are connected to one magnetic flux coupling winding 312 and the connection portion 303, respectively.

  As described above, the scale 300 according to the present embodiment includes the scale track 210 except that the magnetic flux coupling windings 311 and 321 and the magnetic flux coupling windings 312 and 331 are arranged in opposite phases in the X direction. It is arranged in line symmetry at the center.

  The sensor head 400 includes an insulating substrate. On the surface of the insulating substrate facing the scale 300, the sensor track 410 (first sensor track) disposed at a position facing the scale track 310 and the scale track 320 are opposed. A sensor track 420 (second sensor track) disposed at a position where the scale track 330 is located, and a sensor track 430 (third sensor track) disposed at a position facing the scale track 330.

  The sensor track 410 is the same as the sensor track 210 in the first embodiment, and includes a transmission winding 411 corresponding to the transmission winding 211 (an example of a first transmission member) and a reception winding 413 corresponding to the reception winding 213. (First receiving winding). The sensor track 420 is the same as the sensor track 220 in the first embodiment, and includes a transmission winding 421 (an example of a second transmission member) corresponding to the transmission winding 221 and a reception winding corresponding to the reception winding 223. It is constituted by a wire 423 (second receiving winding). However, through holes 427 and 428 penetrating to the back surface of the insulating substrate are formed at both ends of the reception winding 423.

  The sensor track 430 is similar to the sensor track 420, and includes a transmission winding 431 (an example of a third transmission member) corresponding to the transmission winding 421, and a reception winding 433 (third reception winding) corresponding to the reception winding 423. ). However, the transmission winding 421 of the sensor track 420 and the transmission winding 431 of the sensor track 430 constitute one loop connecting the two terminals 432. Further, through holes 437 and 438 penetrating to the back surface of the insulating substrate are formed at both ends of the reception winding 433. Among these, the through hole 438 is connected to the through hole 428 of the sensor track 430 through a winding formed on the back surface of the insulating substrate. On the other hand, the through hole 437 and the through hole 427 of the sensor track 420 are connected to the terminal 436 through a winding formed on the back surface of the insulating substrate.

  As described above, in the sensor head 400 of this embodiment, the transmission winding 421, the reception winding 423, the transmission winding 431, and the reception winding 433 are arranged symmetrically with respect to the sensor track 310. The above is the configuration of the inductive displacement detection device 2.

  In the case of the inductive displacement detection device 2 having the above configuration, the output signal S1 from the terminal 416 of the reception winding 413 and the terminal 436 of the reception winding 423 and the reception winding 433 are caused by the relative movement of the sensor head 400 with respect to the scale 300. Output signal S2 can be obtained. The output signal S1 and the output signal S2 are detected alternately. Then, the inductive displacement detection device 2 detects the ABS position by determining the spatial phase from the output signal S1 by using an IC circuit (not shown), calculating the spatial phase from the output signal S2, and synthesizing these calculated spatial phases. To do.

  As described above, in the case of this embodiment, not only the same effects as in the first embodiment can be obtained, but also the influence of yawing can be further reduced by arranging the scale tracks 320 and 330 symmetrically. Can do.

  In addition, if the magnetic flux coupling winding of the middle scale track is formed with a fine pitch like the magnetic flux coupling winding of the outer scale track that sandwiches the scale track, the middle scale track is doubled to the outer scale track. Therefore, the wiring becomes strict according to the design rule of the printed wiring board. In that respect, according to the present embodiment, the middle scale track (eg, 310 shown in FIG. 4) can increase the pitch of the magnetic flux coupling windings (eg, 311 and 312 shown in FIG. 4). Wiring with a margin can be realized.

[Third Embodiment]
The third embodiment is an application example of the second embodiment, and is an inductive displacement detection device that enables detection of an ABS position in a wide ABS range.

  FIG. 5 is a plan view of a part of the scale 500 and the sense head 600 of the inductive displacement detector 3 according to the third embodiment.

  The inductive displacement detection device 3 includes a scale 500 and a sensor head 600 arranged so as to face the scale 500.

  The scale 500 includes an insulating substrate. On the surface of the insulating substrate facing the sensor head 600, five scale tracks 510 (first scale track), scale track 520 (second scale track) arranged in the Y direction, A scale track 530 (third scale track), a scale track 540 (fourth scale track), and a scale track 550 (fifth scale track) are included.

  The scale tracks 510, 520, and 530 have the same configuration as the scale tracks 310, 320, and 330 in the second embodiment, and thus description thereof is omitted.

  In the scale track 540, a plurality of magnetic flux coupling windings 541 (an example of a fourth magnetic flux coupling member) arranged in the X direction at a pitch P4 = λ2 (λ2 <λ1) are formed. Each magnetic flux coupling winding 541 is a rectangular linear conductor whose longitudinal direction is the X direction. Similarly, the scale track 550 has a plurality of magnetic flux coupling windings 551 (an example of a fifth magnetic flux coupling member) arranged in the X direction at a pitch P5 = λ3 (λ3 <λ2). Each magnetic flux coupling winding 551 is a rectangular linear conductor whose longitudinal direction is the X direction. Further, each magnetic flux coupling winding 551 is connected to one magnetic flux coupling winding 541 by a connection portion 504. Note that the lengths λ1, λ2, and λ3 do not need to satisfy λ1> λ2> λ3 as shown in FIG. 5, and may be different from each other.

  The sensor head 600 includes an insulating substrate, and a sensor track 610 (first sensor) disposed on the surface of the insulating substrate facing the scale 500 at a position facing the scale tracks 510, 520, 530, 540, and 550. Track), sensor track 620 (second sensor track), sensor track 630 (third sensor track), sensor track 640 (fourth sensor track) and sensor track 650 (fifth sensor track).

  Since the sensor tracks 610, 620, and 630 have the same configuration as the sensor tracks 410, 420, and 430 of the second embodiment, description thereof is omitted.

  The sensor track 640 is formed with a rectangular transmission winding 641 (an example of a fourth transmission member) whose longitudinal direction is the X direction. The transmission winding 641 can be magnetically coupled to the magnetic flux coupling winding 541. In addition, one reception winding 643 (fourth reception winding) is disposed inside the transmission winding 641 of the sensor track 640. The reception winding 643 can be magnetically coupled to the magnetic flux coupling winding 541. The reception winding 643 includes a plurality of reception loops 644 arranged in the X direction. The reception loop 644 is a diamond-shaped linear conductor. Adjacent reception loops 644 form a pair loop 645 by being connected at a three-dimensional intersection. The length of the pair loop 645 in the X direction is L4 = λ2, and the length of one reception loop 644 in the X direction is λ2 / 2.

  The sensor track 650 is formed with a rectangular transmission winding 651 (an example of a fifth transmission member) whose longitudinal direction is the X direction. The transmission winding 651 can be magnetically coupled to the magnetic flux coupling winding 551. In addition, one reception winding 653 (fifth reception winding) is disposed inside the transmission winding 651 of the sensor track 650. The reception winding 653 can be magnetically coupled to the magnetic flux coupling winding 551. The reception winding 653 is configured by a plurality of reception loops 654 arranged in the X direction. The reception loop 654 is a diamond-shaped linear conductor. Adjacent reception loops 654 form a pair loop 655 by being connected at a three-dimensional intersection. The length of the pair loop 655 in the X direction is L5 = λ3, and the length of one reception loop 654 in the X direction is λ3 / 2. The above is the configuration of the inductive displacement detection device 3.

  In the case of the inductive displacement detection device 3 having the above configuration, the output signals S1 and S2 similar to the output signals S1 and S2 in the second embodiment are output to the terminals of the reception winding 613 by the relative movement of the sensor head 600 with respect to the scale 500. 616, the reception winding 623 and the terminal 636 of the reception winding 633. Further, by inputting a transmission excitation signal to the transmission winding 651 via the terminal 652, a sinusoidal output signal S4 having a wavelength λ2 can be obtained from the terminal 646 of the reception winding 643. Similarly, by inputting the transmission excitation signal to the transmission winding 641 through the terminal 6642, a sine wave output signal S5 having the wavelength λ3 can be obtained from the terminal 656 of the reception winding 653. The inductive displacement detection device 3 detects the ABS position by calculating the spatial phase from the output signals S1, S2, S4, and S5 by an IC circuit (not shown) and synthesizing the calculated spatial phases.

  In order to obtain a wide ABS range, a plurality of tracks are provided in the Y direction while gradually shifting the pitch of the reception winding, and the phase difference between the output signals from the plurality of tracks may be obtained. However, in this case, since a plurality of tracks are arranged in a wide range in the Y direction, it is easily affected by yawing. In this respect, according to the present embodiment, not only the same effects as those of the second embodiment can be obtained, but also a magnetic flux coupling winding 510 having a wide pitch like the magnetic flux coupling winding 510 of the scale track 510 can be obtained. Since a plurality of tracks can be provided as a reference, a phase error due to yawing can be suppressed, and a favorable ABS position can be determined.

  In the example shown in FIG. 5, the configuration in which the scale tracks 540 and 550 and the sensor tracks 640 and 650 are added to the track configuration of the second embodiment has been described. However, the track configuration of the first embodiment has been described. On the other hand, even if tracks corresponding to the scale tracks 540 and 550 and the sensor tracks 640 and 650 are added, the same effect as in the present embodiment can be obtained.

  Further, even when only one set of scale track and sensor track is added to the track configuration of the first or second embodiment, or when three or more sets are added, the same effect as this embodiment can be obtained. it can.

  1, 2, 3 ... Inductive displacement detection device, 100, 300, 500 ... Scale, 101, 201 ... Insulating substrate, 102, 302, 303, 504 ... Connection part, 110, 120, 310, 320, 330, 510, 520, 530, 540, 550 ... scale track, 111, 121, 311, 321, 331, 541, 551 ... magnetic flux coupling winding, 200, 400, 600 ... Sensor head, 210, 220, 410, 420, 430, 610, 620, 630, 640, 650 ... sensor track, 211, 221, 411, 421, 431, 641, 651 ... transmission winding, 212, 216, 222, 226, 412, 416, 432, 436, 616, 636, 642, 646, 652, 656 ... terminals, 213, 23, 413, 423, 433, 613, 623, 633, 643, 653... Reception winding, 214, 224, 644, 654... Reception loop, 215, 225, 645, 655... Pair loop, 427 428, 437, 438, 627, 628, 637, 638 ... through holes.

Claims (4)

A scale having a first scale track and a second scale track arranged in a second direction orthogonal to the first direction which is the measurement axis direction;
A sensor head having a first sensor track disposed opposite to the first scale track and a second sensor track disposed opposite to the second scale track, and capable of moving relative to the scale in a first direction. ,
The first sensor track has a first transmission member and a first reception winding composed of a plurality of first reception loops arranged in a first direction at a pitch λ1.
The second sensor track includes a second transmission member and a second reception winding composed of a plurality of second reception loops arranged in the first direction at a pitch λ1.
The first scale track has a plurality of first magnetic flux coupling members that are magnetically coupled to the first transmission member and the first reception winding and are arranged in a first direction at a pitch λ1.
The second scale tracks can be magnetically coupled to the second transmission member and the second reception winding, and are arranged in a first direction at a pitch λ1 / N (N is an odd number of 3 or more), and N pieces. each have a one of said first magnetic flux coupling member and connected to the plurality of second flux coupling members have been,
When the sensor head is moved relative to the scale,
When the first single-phase AC signal is input to the second transmission member, the magnetic flux coupling between the second transmission member and the second magnetic flux coupling member, and between the first magnetic flux coupling member and the first reception winding. A first output signal having a wavelength λ1 is output from the first reception winding via magnetic flux coupling,
When the second single-phase AC signal is input to the first transmission member, the magnetic flux coupling between the first transmission member and the first magnetic flux coupling member, and between the second magnetic flux coupling member and the second reception winding. A second output signal having a wavelength λ1 / N is output from the second receiving winding via magnetic flux coupling,
The inductive displacement detection device, wherein the first output signal and the second output signal are detected alternately . The scale has a third scale track arranged to sandwich the first scale track with the second scale track in a second direction;
The sensor head has a third sensor track disposed opposite to the third scale track;
The third sensor track includes a third transmission member, and a third reception winding including a plurality of third reception loops arranged in the first direction at a pitch λ1.
The first scale track is opposite in phase in the first direction with respect to the plurality of first magnetic flux coupling members, and can be magnetically coupled to the first transmission member and the first reception winding. A plurality of antiphase magnetic flux coupling members arranged in the first direction at a pitch λ1,
The third scale track is out of phase in the first direction with respect to the plurality of second reception loops, and can be magnetically coupled to the third transmission member and the third reception winding and has a pitch. The induction-type displacement detection device according to claim 1, further comprising a plurality of third magnetic flux members arranged in a first direction at λ1 / N and connected to the N antiphase magnetic flux coupling members one by one. . The scale further includes a fourth scale track aligned with the first scale track in a second direction;
The sensor head further includes a fourth sensor track disposed opposite to the fourth scale track,
The fourth sensor track includes a fourth transmission member and a fourth reception winding including a plurality of fourth reception loops arranged in the first direction at a pitch λ2 (λ2 ≠ λ1),
The fourth scale track has a plurality of fourth magnetic flux coupling members that can be magnetically coupled to the fourth transmission member and the fourth reception winding and are arranged in a first direction at a pitch λ2. The inductive displacement detection device according to 1 or 2. The inductive displacement detection device according to any one of claims 1 to 3, wherein N is 5.

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