Position detection device

Abstract

A position detection device is provided with: a substrate (30); transmitting coils (31, 32) which are disposed on the substrate and which generate a magnetic field by the supply of an alternating current; targets (22, 23, 24, 25) that are disposed so as to face the substrate, move in a predetermined movement direction (Dc), and generate a magnetic field that counteracts the magnetic field by causing eddy current to flow through the magnetic field; and a plurality of reception coils (34, 35, 36, 37, 40, 41, 42, 43) which are arranged on the substrate so as to be aligned in the movement direction and which receive the magnetic field generated by the transmission coils. In the substrate, a region occupied by the plurality of receiving coils is set as a receiving region (301, 302, 303, 304). (M-1) / 4 * w1lt, where w1 is the width of the receiving region in the direction of movement, w2 is the width of the target in the direction of movement, M is an integer of 1 or more and 3 or less, and w3 = M / 4 * w1, where w1 is the width of the receiving region in the direction of movement, w2 is the width of the target in the direction of movement, and w3 is the reference width; w2lt; w2lt; w3.

Description

[0001] Cross-references of related applications

[0002] This application is based on Japanese Patent Application No. 2023-5863 filed on January 18, 2023, and the contents described therein are cited herein by reference. Technical Field

[0003] The present disclosure relates to a position detection device. Background Art

[0004] As a position detection device, a rotation angle detection device using electromagnetic induction is known. For example, the rotation angle sensor described in Patent Document 1 includes a substrate, a transmitting coil and a receiving coil arranged on the substrate, and a target placed opposite to the substrate. The transmitting coil generates a magnetic field by being supplied with a high-frequency current, and the receiving coil receives the magnetic field. Eddy current flows through the target through the magnetic field from the transmitting coil, generating a magnetic field that cancels out the magnetic field, and the position of the target can be detected by using the property that the output of the receiving coil changes according to the position of the target. There are four receiving coils arranged in an array, and the four receiving coils output sinusoidal signals that are offset by 0.25 cycles. In addition, the signal amplitude is amplified by connecting the first and third receiving coils in series and the second and fourth receiving coils in series.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2021-71340 Summary of the invention

[0008] In the above configuration, the amplitude of the signal increases by allowing the magnetic flux from the target to pass through only one of the first and third receiving coils. Also, the amplitude of the signal increases by allowing the magnetic flux from the target to pass through only one of the second and fourth receiving coils.

[0009] In order to increase the amplitude of the signal, the width of the target can be considered to be 1 / 4, 1 / 2 or 3 / 4 of the width of the area where the receiving coils are arranged. However, the magnetic flux generated from the target also flows from the target to the outside in a direction parallel to the substrate surface. Therefore, if the width of the target is set to 1 / 2 of the width of the area where the receiving coils are arranged, when the target is opposite to the second and third receiving coils, the magnetic flux from the target also enters the first and fourth receiving coils, the signal amplitude becomes smaller and the S / N ratio decreases.

[0010] In view of the above-mentioned problems, an object of the present disclosure is to provide a position detection device capable of improving the S / N ratio.

[0011] According to one aspect of the present disclosure, a position detection device includes: a substrate; a transmitting coil disposed on the substrate and generating a magnetic field by supplying an alternating current; a target configured to face the substrate and move in a predetermined moving direction, and generating an eddy current through the magnetic field, thereby generating a magnetic field that cancels the magnetic field; and a plurality of receiving coils disposed on the substrate in an arrangement along the moving direction, receiving the magnetic field generated by the transmitting coil. In the substrate, a region occupied by the plurality of receiving coils is defined as a receiving region; a width of the receiving region in the moving direction is defined as w1, a width of the target in the moving direction is defined as w2, M is an integer greater than or equal to 1 and less than or equal to 3, and a reference width is defined as w3 = M / 4 × w1, and (M - 1) / 4 × w1 < w2 < w3.

[0012] Thus, since (M - 1) / 4 × w1 < w2 < w3, it is possible to form a state in which one of the two receiving coils included in the plurality of receiving coils is covered by the target and the magnetic flux entering the other is reduced. Therefore, it is possible to increase the amplitude of the signal output from the receiving coil and improve the S / N ratio.

[0013] In addition, the reference numerals in parentheses assigned to each component etc. represent an example of the correspondence relationship between the component etc. and the specific components etc. described in the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic view showing a schematic structure of the position detection device of the first embodiment as viewed in a direction along the axial direction of the component.

[0015] Figure 2 is a schematic view showing Figure 1 a cross-sectional view taken along line II—II, which is a longitudinal cross-sectional view of the position detection device.

[0016] Figure 3 is a schematic view showing Figure 1 a cross-sectional view taken along line III—III, which is a longitudinal cross-sectional view of the position detection device shown in a different orientation from Figure 2 the above.

[0017] Figure 4 is a plan view showing the rotating component included in the position detection device of the first embodiment as an individual.

[0018] Figure 5 is a view showing the substrate included in the position detection device of the first embodiment as an individual and schematically showing each coil in the substrate.

[0019] Figure 6 is a view from the VI direction of Figure 5 the above, which is a view schematically showing each transmitting coil in the substrate.

[0020] Figure 7 is with Figure 5 The equivalent figure is the Figure 5 A schematic diagram showing a receiving area formed by the receiving coil instead of the receiving coil shown in FIG.

[0021] Figure 8 This is a block diagram of the position detection device according to the first embodiment.

[0022] Fig. 9 The diagrams respectively illustrate the waveform of the first voltage value generated in the first receiving coil and the waveform of the second voltage value generated in the second receiving coil in the first embodiment.

[0023] Fig.10 Yes means Figure 1 Cross-sectional view of section X-X.

[0024] Fig.11 is a cross-sectional view of a position detection device according to a second embodiment, Fig.10 Quite a picture.

[0025] Fig.12 In the third embodiment, the substrate of the position detection device is shown as a separate entity, and each coil in the substrate is schematically shown. Figure 5 Quite a picture.

[0026] Fig.13 In the fourth embodiment, the substrate of the position detection device is shown as a separate entity, and each coil in the substrate is schematically shown. Figure 5 Quite a picture.

[0027] Fig.14 In the fifth embodiment, the substrate of the position detection device is shown as a separate entity, and each coil in the substrate is schematically shown. Figure 5 Quite a picture. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the present disclosure will be described based on the drawings. In addition, in the following embodiments, the same or equivalent parts are given the same reference numerals and described.

[0029] (First embodiment)

[0030] In this embodiment, an example in which the position detection device 1 is used to detect the rotational position of a brake pedal or an accelerator pedal of a vehicle pedal device will be described. In the following description, the brake pedal or the accelerator pedal may be simply referred to as a pedal.

[0031] like Figure 1 to Figure 3 As shown, the position detection device 1 of this embodiment includes a rotating member 20 and a substrate 30. Figure 1 to Figure 3 The rotation axis CL shown in is the rotation axis 70 of the pedal and the rotation center of the rotating component 20. In the description of this embodiment, the axial direction Da of the rotation axis CL is also referred to as the component axial direction Da, the radial direction Dr of the rotation axis CL is also referred to as the component radial direction Dr, and the circumferential direction Dc of the rotation axis CL is also referred to as the component circumferential direction Dc. These directions Da, Dr, and Dc are mutually intersecting directions, and strictly speaking, are mutually perpendicular directions. In addition, Figure 1 It means Figure 2 Cross-sectional view of section II.

[0032] The rotating member 20 is made of metal and is formed into a flat plate shape having a thickness in the member axial direction Da. Figure 1 to Figure 4 As shown, the rotating member 20 is connected to the rotating shaft 70 of the pedal so as not to rotate relative to each other. For example, the rotating member 20 can be connected to the rotating shaft 70 so as not to rotate relative to each other by a rotation-blocking key member or by being welded to the rotating shaft 70 so as not to rotate relative to each other.

[0033] The rotating member 20 is supported by the non-rotating member via the rotating shaft 70 so as to be rotatable about a predetermined rotation axis CL, and rotates integrally with the pedal and the rotating shaft 70. Therefore, the rotation position of the pedal can be detected by detecting the rotation position of the rotating member 20. That is, the rotation position of the rotating member 20 is both the rotation position of the pedal and the rotation position of the rotating shaft 70 as the object to be detected.

[0034] In addition, since the rotating member 20 is connected to the rotating shaft 70 of the pedal, it does not rotate once around the rotation axis CL, but reciprocates within a predetermined angular range around the rotation axis CL in response to the pedal being depressed. Figure 1 In FIG. 1 , a part of the outer shape of each target 22 to 25 of the rotating member 20 at the end position during the reciprocating motion is shown by a two-dot chain line.

[0035] The rotating component 20 has a connecting portion 21, two first targets 22, 23 and two second targets 24, 25. That is, the two first targets 22, 23 and the two second targets 24, 25 included in the rotating component 20 rotate integrally around the rotation axis CL. And, as the pedal is depressed, the two first targets 22, 23 and the two second targets 24, 25 reciprocate in the component circumferential direction Dc. In the present embodiment, the component circumferential direction Dc corresponds to the specified moving direction of the present disclosure.

[0036] For example, the rotating member 20 is configured as a single part including its connecting portion 21, two first targets 22, 23, and two second targets 24, 25. For example, the rotating member 20 is formed into a flat plate with a uniform thickness in the member axial direction Da, so the thicknesses in the member axial direction Da of the four targets 22 to 25 are the same size. In the description of this embodiment, the two first targets 22, 23 and the two second targets 24, 25 are sometimes collectively referred to as targets 22 to 25.

[0037] The connection portion 21 is arranged at the center of the rotating member 20 and is in the shape of a ring centered on the rotation axis CL. An insertion hole 21a is formed inside the connection portion 21, which penetrates the connection portion 21 in the member axial direction Da, and the rotating shaft 70 is inserted into the insertion hole 21a in a manner that it cannot rotate relative to the connection portion 21. That is, the rotating member 20 is connected to the rotating shaft 70 by the connection portion 21.

[0038] The two first targets 22 and 23 are formed so as to protrude outward from the connection portion 21 in the component radial direction Dr, and the two second targets 24 and 25 are also formed so as to protrude outward from the connection portion 21 in the component radial direction Dr.

[0039] The first target 22, which is one of the two first targets 22 and 23, is arranged on the opposite side of the rotation axis CL relative to the first target 23, which is the other of the two first targets 22 and 23. In addition, the second target 24, which is one of the two second targets 24 and 25, is arranged on the opposite side of the rotation axis CL relative to the second target 25, which is the other of the two second targets 24 and 25.

[0040] In detail, the four targets 22 to 25 are arranged in the order of the first one-side target 22, the second one-side target 24, the first other-side target 23, and the second other-side target 25, and are arranged at equal intervals with each other in one side of the component circumferential direction Dc. Specifically, the equal interval is a 90-degree interval. For example, when viewed in the direction along the component axial direction Da, the four targets 22 to 25 are arranged as a whole in point symmetry with the rotation axis CL as the center.

[0041] The first one-side target 22 is formed on one side of the component axial direction Da, and has an opposing surface 22a opposed to the other surface 30b of the substrate 30. The first other-side target 23 is also formed on one side of the component axial direction Da, and has an opposing surface 23a opposed to the other surface 30b of the substrate 30. In addition, the second one-side target 24 is also formed on one side of the component axial direction Da, and has an opposing surface 24a opposed to the other surface 30b of the substrate 30. The second other-side target 25 is also formed on one side of the component axial direction Da, and has an opposing surface 25a opposed to the other surface 30b of the substrate 30. These opposing surfaces 22a to 25a are formed parallel to the other surface 30b of the substrate 30.

[0042] The first target 22 has an end edge 221 disposed on one side of the component circumferential direction Dc, and another end edge 222 disposed on the other side of the component circumferential direction Dc. Furthermore, the first target 22 is fan-shaped in a manner that the width increases in the component circumferential direction Dc as it approaches the outer side of the component radial direction Dr. Therefore, when observed in the direction of the component axial direction Da, the one end edge 221 and the other end edge 222 of the first target 22 extend in a straight line along the component radial direction Dr, respectively. That is, the one end edge 221 and the other end edge 222 of the first target 22 extend in a manner that is orthogonal to the component circumferential direction Dc, that is, the moving direction of the first target 22.

[0043] Moreover, the first other target 23, the second one target 24, and the second other target 25 also have the same fan-shaped shape as the first one target 22. In the present embodiment, all of the four targets 22 to 25 have the same shape.

[0044] Therefore, when viewed in the direction of the component axial direction Da, in the first other target 23, one end edge 231 provided on one side of the component circumferential direction Dc and the other end edge 232 provided on the other side of the component circumferential direction Dc also extend in a straight line along the component radial direction Dr. In addition, when viewed in the direction of the component axial direction Da, in the second one target 24, one end edge 241 provided on one side of the component circumferential direction Dc and the other end edge 242 provided on the other side of the component circumferential direction Dc also extend in a straight line along the component radial direction Dr. In addition, when viewed in the direction of the component axial direction Da, in the second other target 25, one end edge 251 provided on one side of the component circumferential direction Dc and the other end edge 252 provided on the other side of the component circumferential direction Dc also extend in a straight line along the component radial direction Dr.

[0045] In the present embodiment, since the four targets 22 to 25 are all of the same shape and rotate integrally as described above, the operating ranges W1a, W1b, W2a, and W2b of the respective targets 22 to 25 have the same length in the component circumferential direction Dc.

[0046] In addition, the motion range W1a of the first one-side target 22 is the maximum range in the component circumferential direction Dc reached by the first one-side target 22 as the first one-side target 22 reciprocates, and the first one-side target 22 reciprocates in the component circumferential direction Dc within the motion range W1a. In addition, the motion range W1b of the first other-side target 23 is the maximum range in the component circumferential direction Dc reached by the first other-side target 23 as the first other-side target 23 reciprocates, and the first other-side target 23 reciprocates in the component circumferential direction Dc within the motion range W1b. In addition, the motion range W2a of the second one-side target 24 is the maximum range in the component circumferential direction Dc reached by the second one-side target 24 as the second one-side target 24 reciprocates, and the second one-side target 24 reciprocates in the component circumferential direction Dc within the motion range W2a. The operating range W2b of the second other target 25 is the maximum range reached by the second other target 25 in the component circumferential direction Dc as the second other target 25 reciprocates. The second other target 25 reciprocates in the component circumferential direction Dc within the operating range W2b.

[0047] like Figure 1 to Figure 3 , Figure 5 As shown, the substrate 30 is a multi-layer printed substrate formed with a wiring pattern and mounted with electronic components (not shown). The substrate 30 has a planar surface 30a and another surface 30b that are orthogonal to the component axial direction Da. That is, the normal direction of the substrate 30 is consistent with the component axial direction Da. One surface 30a of the substrate 30 is set on one side of the component axial direction Da in the substrate 30, and the other surface 30b of the substrate 30 is set on the other side of the substrate 30 opposite to the one side of the component axial direction Da.

[0048] The base plate 30 is a non-rotating member that does not rotate relative to the vehicle body, etc. Therefore, the rotating member 20 rotates relative to the base plate 30 .

[0049] The substrate 30 is arranged on one side of the component axial direction Da relative to the four targets 22 to 25. Furthermore, the other surface 30b of the substrate 30 is opposed to the respective opposing surfaces 22a to 25a of the four targets 22 to 25 at an axial interval AG in the component axial direction Da. The axial interval AG is the same between the substrate 30 and each of the four targets 22 to 25.

[0050] The substrate 30 is formed in a disk shape with the rotation axis CL as the center, and a through hole 30c is formed in the center of the substrate 30 so as to penetrate the substrate 30 in the component axial direction Da. The rotation axis 70 is inserted through the through hole 30c.

[0051] like Figure 5 , Figure 6As shown, the substrate 30 has a first transmitting coil 31 and a second transmitting coil 32 formed as a wiring pattern. In addition, the substrate 30 also has two first receiving coils 34, 36, two second receiving coils 35, 37, two third receiving coils 40, 42, and two fourth receiving coils 41, 43 formed as a wiring pattern. That is, all the transmitting coils 31, 32 and all the receiving coils 34 to 37, 40 to 43 provided in the position detection device 1 are formed on a single substrate 30.

[0052] The coils 31, 32, 34 to 37, 40 to 43 of the substrate 30 are connected to the signal processing units 47 and 48 (see FIG. 1 ) composed of ICs or the like mounted on the substrate 30 via connection wiring patterns not shown. Figure 8 ) connection. In addition, Figure 5 , Figure 6 In order to make the illustration easier to see, the coils 31, 32, 34 to 37, and 40 to 43 are simply shown. This also applies to the following figures showing the coils 31, 32, 34 to 37, and 40 to 43.

[0053] The first and second transmission coils 31 and 32 are formed so as to overlap each other when viewed in the direction along the component axial direction Da, but are arranged offset in the thickness direction of the substrate 30, that is, in the component axial direction Da. For example, the first transmission coil 31 is arranged away from the second transmission coil 32 on one side in the component axial direction Da.

[0054] The first and second transmitting coils 31 and 32 are respectively wound one or more times and formed into an annular shape along the component circumferential direction Dc. Furthermore, when viewed along the component axial direction Da, the first and second transmitting coils 31 and 32 are respectively formed so as to surround all the receiving coils 34 to 37 and 40 to 43 of the substrate 30. In other words, when viewed along the component axial direction Da, all the receiving coils 34 to 37 and 40 to 43 are arranged inside the first transmitting coil 31 and inside the second transmitting coil 32.

[0055] Therefore, when an alternating current flows through the first transmitting coil 31, an induced current flows through all the receiving coils 34 to 37 and 40 to 43 by electromagnetic induction caused by energizing the first transmitting coil 31. Furthermore, even if an alternating current flows through the second transmitting coil 32, an induced current flows through all the receiving coils 34 to 37 and 40 to 43 by electromagnetic induction caused by energizing the second transmitting coil 32. In order to prevent the magnetic fields generated by the first transmitting coil 31 and the second transmitting coil 32 from canceling each other, for example, alternating currents of the same phase and the same frequency flow through the first transmitting coil 31 and the second transmitting coil 32.

[0056] The first receiving coil 34, which is one of the two first receiving coils 34 and 36, and the second receiving coil 35, which is one of the two second receiving coils 35 and 37, are coils for detecting the position of the first target 22 in the component circumferential direction Dc. That is, the first receiving coil 34 and the second receiving coil 35 each output a detection signal corresponding to the position of the first target 22.

[0057] In addition, the first other receiving coil 36, which is the other of the two first receiving coils 34 and 36, and the second other receiving coil 37, which is the other of the two second receiving coils 35 and 37, are coils for detecting the position of the first other target 23 in the component circumferential direction Dc. That is, the first other receiving coil 36 and the second other receiving coil 37 each output a detection signal corresponding to the position of the first other target 23.

[0058] In addition, the third receiving coil 40, which is one of the two third receiving coils 40 and 42, and the fourth receiving coil 41, which is one of the two fourth receiving coils 41 and 43, are coils for detecting the position of the second target 24 in the component circumferential direction Dc. That is, the third receiving coil 40 and the fourth receiving coil 41 output detection signals corresponding to the position of the second target 24, respectively.

[0059] Furthermore, the third other receiving coil 42, which is the other of the two third receiving coils 40 and 42, and the fourth other receiving coil 43, which is the other of the two fourth receiving coils 41 and 43, are coils for detecting the position of the second other target 25 in the component circumferential direction Dc. That is, the third other receiving coil 42 and the fourth other receiving coil 43 each output a detection signal corresponding to the position of the second other target 25.

[0060] In addition, each receiving coil 34 to 37, 40 to 43 is configured so as to avoid mutual interference (i.e., avoid overlapping) by appropriately connecting different wiring layers through vias. Figure 5 and Figure 5 In the corresponding figures described later, the illustration of the conductive hole of the substrate 30 is appropriately omitted. In addition, the detection signal output by each receiving coil 34 to 37, 40 to 43 is, for example, a voltage value. In addition, the detection signal output by the first receiving coil 34 corresponds to, for example, Fig. 9 The first voltage value V1 shown in FIG. 1 corresponds to the detection signal output by the second receiving coil 35, for example, Fig. 9 The second voltage value V2 is shown.

[0061] The first receiving coil 34 has a first spiral portion 34a and a second spiral portion 34b. When observed in the direction of the component axial direction Da, the first and second spiral portions 34a and 34b are respectively in the shape of a spiral pattern. In other words, when observed in the direction of the component axial direction Da, the first and second spiral portions 34a and 34b are respectively formed in a manner of describing a plane curve wound into a spiral shape. The first and second spiral portions 34a and 34b are connected in series, for example, via a connection wiring pattern not shown in the figure. In addition, the outer shapes of the first and second spiral portions 34a and 34b are not limited to Figure 5 The shape shown can also be other shapes such as a circle.

[0062] The same is true for the other receiving coils 35 to 37 and 40 to 43. That is, the second one-side receiving coil 35 has a first spiral portion 35a and a second spiral portion 35b connected in series with each other. In addition, the first other-side receiving coil 36 has a first spiral portion 36a and a second spiral portion 36b connected in series with each other, and the second other-side receiving coil 37 has a first spiral portion 37a and a second spiral portion 37b connected in series with each other.

[0063] In addition, the third one-side receiving coil 40 has a first spiral portion 40a and a second spiral portion 40b connected in series, and the fourth one-side receiving coil 41 has a first spiral portion 41a and a second spiral portion 41b connected in series. In addition, the third other-side receiving coil 42 has a first spiral portion 42a and a second spiral portion 42b connected in series, and the fourth other-side receiving coil 43 has a first spiral portion 43a and a second spiral portion 43b connected in series. These spiral portions 35a to 43b are similar to the spiral portions 34a and 34b of the first one-side receiving coil 34, and have a spiral pattern shape when viewed in the direction of the component axial direction Da. The above-mentioned spiral portions 35a to 43b refer to spiral portions 35a, 35b, 36a, 36b, 37a, 37b, 40a, 40b, 41a, 41b, 42a, 42b, 43a, and 43b.

[0064] The spiral portions 34a and 34b of the first one-side receiving coil 34 are arranged to overlap with the first one-side target 22 on one side of the component axial direction Da at a certain position within the movement range W1a of the first one-side target 22. Furthermore, the spiral portions 35a and 35b of the second one-side receiving coil 35 are also arranged to overlap with the first one-side target 22 on one side of the component axial direction Da at a certain position within the movement range W1a of the first one-side target 22.

[0065] Furthermore, these vortex-shaped portions 34a, 34b, 35a, 35b are arranged in the order of the first vortex-shaped portion 34a, the first vortex-shaped portion 35a, the second vortex-shaped portion 34b, and the second vortex-shaped portion 35b from one side of the component circumferential direction Dc to the other side. In addition, these vortex-shaped portions 34a, 34b, 35a, 35b form one area when viewed in the direction of the component axial direction Da.

[0066] That is, the first receiving coil 34 and the second receiving coil 35 form a first receiving area 301 occupied by these receiving coils 34 and 35 in the substrate 30. Furthermore, the first receiving coil 34 and the second receiving coil 35 constitute a first receiving coil group 301a which is a combination of these receiving coils 34 and 35.

[0067] As described above, the spiral portions 36a and 36b of the first other side receiving coil 36 are arranged so as to overlap with the first other side target 23 on one side of the component axial direction Da at a certain position within the operating range W1b of the first other side target 23. Furthermore, the spiral portions 37a and 37b of the second other side receiving coil 37 are also arranged so as to overlap with the first other side target 23 on one side of the component axial direction Da at a certain position within the operating range W1b of the first other side target 23.

[0068] Furthermore, these vortex-shaped portions 36a, 36b, 37a, 37b are arranged in the order of the first vortex-shaped portion 36a, the first vortex-shaped portion 37a, the second vortex-shaped portion 36b, and the second vortex-shaped portion 37b from one side of the component circumferential direction Dc to the other side. In addition, these vortex-shaped portions 36a, 36b, 37a, 37b form one area when viewed in the direction of the component axial direction Da.

[0069] That is, the first other receiving coil 36 and the second other receiving coil 37 form a first other receiving area 302 occupied by these receiving coils 36 and 37 in the substrate 30. Furthermore, the first other receiving coil 36 and the second other receiving coil 37 constitute a first other receiving coil group 302a which is a combination of these receiving coils 36 and 37.

[0070] In addition, the spiral portions 40a and 40b of the third one-side receiving coil 40 are arranged to overlap with the second one-side target 24 on one side of the component axial direction Da at a certain position within the movement range W2a of the second one-side target 24. In addition, the spiral portions 41a and 41b of the fourth one-side receiving coil 41 are also arranged to overlap with the second one-side target 24 on one side of the component axial direction Da at a certain position within the movement range W2a of the second one-side target 24.

[0071] Furthermore, these vortex-shaped portions 40a, 40b, 41a, 41b are arranged in the order of the first vortex-shaped portion 40a, the first vortex-shaped portion 41a, the second vortex-shaped portion 40b, and the second vortex-shaped portion 41b from one side of the component circumferential direction Dc to the other side. In addition, these vortex-shaped portions 40a, 40b, 41a, 41b form one area when viewed in the direction of the component axial direction Da.

[0072] That is, the third one receiving coil 40 and the fourth one receiving coil 41 form the second one receiving area 303 occupied by these receiving coils 40 and 41 in the substrate 30. Furthermore, the third one receiving coil 40 and the fourth one receiving coil 41 constitute the second one receiving coil group 303a which is a combination of these receiving coils 40 and 41.

[0073] Furthermore, the spiral portions 42a and 42b of the third other side receiving coil 42 are arranged so as to overlap with the second other side target 25 on one side of the component axial direction Da at a certain position within the movement range W2b of the second other side target 25. Furthermore, the spiral portions 43a and 43b of the fourth other side receiving coil 43 are also arranged so as to overlap with the second other side target 25 on one side of the component axial direction Da at a certain position within the movement range W2b of the second other side target 25.

[0074] Furthermore, these vortex-shaped portions 42a, 42b, 43a, 43b are arranged in the order of the first vortex-shaped portion 42a, the first vortex-shaped portion 43a, the second vortex-shaped portion 42b, and the second vortex-shaped portion 43b from one side of the component circumferential direction Dc to the other side. In addition, these vortex-shaped portions 42a, 42b, 43a, 43b form one area when viewed in the direction of the component axial direction Da.

[0075] That is, the third other receiving coil 42 and the fourth other receiving coil 43 form a second other receiving area 304 occupied by these receiving coils 42 and 43 in the substrate 30. Furthermore, the third other receiving coil 42 and the fourth other receiving coil 43 constitute a second other receiving coil group 304a which is a combination of these receiving coils 42 and 43.

[0076] Figure 7 Yes Figure 5 The receiving coils 34 to 37 and 40 to 43 are replaced with the above-mentioned receiving areas 301 , 302 , 303 , and 304 .

[0077] like Figure 5 , Figure 7As shown, the vortex-shaped portions 34a to 43b of the receiving coils 34 to 37, 40 to 43 are arranged at equal intervals in the circumferential direction Dc of the component in a manner that forms a circular ring shape with the rotation axis CL as the center. That is, the four receiving areas 301 to 304 are also arranged in the circumferential direction Dc of the component in a manner that forms a circular ring shape with the rotation axis CL as the center. The above-mentioned vortex-shaped portions 34a to 43b refer to the vortex-shaped portions 34a, 34b, 35a, 35b, 36a, 36b, 37a, 37b, 40a, 40b, 41a, 41b, 42a, 42b, 43a, 43b.

[0078] Furthermore, the four receiving areas 301 to 304 are arranged from one side to the other side of the component circumferential direction Dc in the order of the first one-side receiving area 301, the second other-side receiving area 304, the first other-side receiving area 302, and the second one-side receiving area 303. Specifically, the four receiving areas 301 to 304 are arranged at 90-degree intervals in the component circumferential direction Dc with the rotation axis CL as the center.

[0079] Therefore, the first one-side receiving area 301 is arranged on the opposite side of the rotation axis CL relative to the first other-side receiving area 302, and the second one-side receiving area 303 is arranged on the opposite side of the rotation axis CL relative to the second other-side receiving area 304. That is, the first one-side receiving coil group 301a is arranged on the opposite side of the rotation axis CL relative to the first other-side receiving coil group 302a, and the second one-side receiving coil group 303a is arranged on the opposite side of the rotation axis CL relative to the second other-side receiving coil group 304a.

[0080] In addition, although it is clearly stated, in the component circumferential direction Dc, the end position P1 on one side of the first one receiving area 301 (i.e., the circumferential one end position P1) coincides with the end position on one side of the first one receiving coil 34 (i.e., the end position on one side of the first spiral portion 34a). In addition, in the component circumferential direction Dc, the end position P2 on the other side of the first one receiving area 301 (i.e., the circumferential other end position P2) coincides with the end position on the other side of the second one receiving coil 35 (i.e., the end position on the other side of the second spiral portion 35b). This relationship is the same for the first other receiving area 302, the second one receiving area 303, and the second other receiving area 304.

[0081] like Figure 1 , Figure 7As shown, the first one-side target 22 reciprocates in the component circumferential direction Dc within the movement range W1a of the first one-side target 22 as described above. However, the movement range W1a of the first one-side target 22 is configured so that the first one-side target 22 does not overlap with the second one-side receiving area 303 and the second other-side receiving area 304 on the other side of the component axial direction Da. In other words, the first one-side target 22 reciprocates within a range that deviates from the second one-side receiving area 303 and the second other-side receiving area 304 in the component circumferential direction Dc.

[0082] The same is true for the other motion ranges W1b, W2a, and W2b. That is, the motion range W1b of the first other target 23 is configured so that the first other target 23 does not overlap with the second one receiving area 303 and the second other receiving area 304 on the other side of the component axial direction Da. In addition, the motion range W2a of the second one target 24 is configured so that the second one target 24 does not overlap with the first one receiving area 301 and the first other receiving area 302 on the other side of the component axial direction Da. In addition, the motion range W2b of the second other target 25 is configured so that the second other target 25 does not overlap with the first one receiving area 301 and the first other receiving area 302 on the other side of the component axial direction Da.

[0083] In more detail, the end position of the motion range W1a on one side in the component circumferential direction Dc coincides with the circumferential end position P1 of the first one receiving area 301. In addition, the end position of the motion range W1a on the other side in the component circumferential direction Dc coincides with the circumferential end position P2 of the first one receiving area 301. Furthermore, the first one target 22 reciprocates in the component circumferential direction Dc in a manner that does not exceed the range of the other side relative to the circumferential end position P1 of the first one receiving area 301 and the one side relative to the circumferential end position P2 of the first one receiving area 301. This is also the case with respect to the positional relationship between the other targets 23, 24, 25 and the receiving areas 302, 303, 304.

[0084] In addition, the motion range W1a of the first one-side target 22 is symmetrical in the component circumferential direction Dc with reference to the center position 301b of the first one-side receiving area 301 in the component circumferential direction Dc. Similarly, the motion range W1b of the first other-side target 23 is symmetrical in the component circumferential direction Dc with reference to the center position 302b of the first other-side receiving area 302 in the component circumferential direction Dc. In addition, the motion range W2a of the second one-side target 24 is symmetrical in the component circumferential direction Dc with reference to the center position 303b of the second one-side receiving area 303 in the component circumferential direction Dc. In addition, the motion range W2b of the second other-side target 25 is symmetrical in the component circumferential direction Dc with reference to the center position 304b of the second other-side receiving area 304 in the component circumferential direction Dc.

[0085] like Figure 8 As shown, various electronic components are mounted on the substrate 30 in addition to the coils 31, 32, 34 to 37, 40 to 43 described above. Specifically, the substrate 30 is also mounted with a plurality of capacitors 451, 452, 461, 462, an IC constituting a first signal processing unit 47, an IC constituting a second signal processing unit 48, a first terminal 49, a second terminal 50, and the like.

[0086] Furthermore, the first transmitting coil 31, the two first receiving coils 34 and 36, the two second receiving coils 35 and 37, the two capacitors 451 and 452, the first signal processing unit 47, and the first terminal 49 constitute a first system 305. On the other hand, the second transmitting coil 32, the two third receiving coils 40 and 42, the two fourth receiving coils 41 and 43, the two capacitors 461 and 462S, the second signal processing unit 48, and the second terminal 50 constitute a second system 306. Since the first system 305 and the second system 306 are independent circuits, the position detection device 1 can detect the rotation position of the rotating member 20 by the other even if one of the first system 305 and the second system 306 fails.

[0087] The first and second signal processing units 47 and 48 respectively have a structure as a vehicle-mounted microcomputer equipped with a CPU, RAM, ROM, non-volatile rewritable memory, etc., which are not shown in the figure. That is, the first and second signal processing units 47 and 48 respectively read and execute a computer program stored in a ROM or a non-volatile rewritable memory which is a recording medium of a non-transient entity. By executing the computer program, the method corresponding to the computer program is executed. Such a structure is also the same for the electronic control device 72 described later. CPU is the abbreviation of Central Processing Unit, ROM is the abbreviation of Read Only Memory, and RAM is the abbreviation of Random Access Memory.

[0088] The first signal processing unit 47 is connected to the first transmitting coil 31, the two first receiving coils 34, 36, and the two second receiving coils 35, 37. In addition, between the two ends of the first transmitting coil 31 and the first signal processing unit 47, for example, two capacitors 451, 452 are connected in series, and the portion connecting the capacitors 451, 452 to each other is connected to the ground potential. In addition, the first signal processing unit 47 is connected to the electronic control device 72 provided outside the position detection device 1 via the first terminal 49 fixed to the substrate 30.

[0089] The connection relationship around the second signal processing unit 48 is the same. That is, the second transmitting coil 32, the two third receiving coils 40, 42 and the two fourth receiving coils 41, 43 are connected to the second signal processing unit 48 respectively. In addition, between the two ends of the second transmitting coil 32 and the second signal processing unit 48, for example, two capacitors 461, 462 are connected in series, and the portion connecting the capacitors 461, 462 to each other is connected to the ground potential. In addition, the second signal processing unit 48 is connected to the external electronic control device 72 via the second terminal 50 fixed to the substrate 30. In this way, the first signal processing unit 47 and the second signal processing unit 48 respectively output the rotation position (in other words, the rotation angle) of the rotating member 20 to the electronic control device 72.

[0090] Next, the operation of the first signal processing unit 47 will be described.

[0091] like Figure 8 As shown in FIG. 1 , the first signal processing unit 47 includes an oscillator 471 and a receiver 472. The oscillator 471 is connected to both ends of the first transmitting coil 31, and applies an alternating current of a predetermined frequency to the first transmitting coil 31. As a result, the first transmitting coil 31 generates a magnetic field in the axial direction Da of the receiving coils 34 to 37, 40 to 43. Due to this magnetic field, an induced current flows through the receiving coils 34 to 37, 40 to 43, respectively.

[0092] The receiving unit 472 is connected to both ends of the first and second receiving coils 34, 36, 35, and 37. The receiving unit 472 obtains a converted signal (i.e., Fig. 9 At the same time, the receiving unit 472 also obtains a conversion signal (ie, Fig. 9 The second voltage value V2).

[0093] In addition, the spiral portions 34a, 34b, 35a, and 35b respectively output different electrical signals represented by the following equations (1) to (4).

[0094] sin + =Asin(θ+α)…(1)

[0095] sin － =Asin(θ-α)…(2)

[0096] cos + =Acos(θ+α)…(3)

[0097] cos － =Acos(θ-α)…(4)

[0098] A is the amplitude, which is the same in the spiral parts 34a, 34b, 35a, and 35b. θ is the rotation angle (electrical angle: deg), which changes in a 360° cycle. α is the phase of the electrical angle. In order to eliminate the high-order components superimposed on the detection signals output from the first receiving coil 34 and the second receiving coil 35, α is set to an appropriate value.

[0099] In order to simplify the description, the signal represented by equation (1) is referred to as sin + signal, the signal represented by equation (2) is called sin － signal, the signal represented by equation (3) is called cos + signal, the signal represented by equation (4) is called cos － Signal.

[0100] As described above, the first vortex portion 34a outputs sin + signal, the second vortex portion 34b outputs sin － The first receiving coil 34 has a structure in which the first and second spiral parts 34a and 34b are connected in series, and the output is sin + Signal and sin － The signal after the signal is synthesized (hereinafter referred to as the sin signal) is used as the detection signal. In addition, the first vortex-shaped portion 34a and the second vortex-shaped portion 34b are connected in series, so that the first receiving coil 34 outputs the sin signal to the receiving unit 472. + Signal and sin － The differential signal after signal synthesis.

[0101] On the other hand, the first vortex portion 35a outputs cos + signal, the second vortex portion 35b outputs cos －The second receiving coil 35 has a structure in which the first and second spiral parts 35a and 35b are connected in series, and outputs cos + Signal and cos － The signal after the signal is synthesized (hereinafter referred to as the cosine signal) is used as the detection signal. The second receiving coil 35 is the same as the first receiving coil 34, and outputs the cosine signal to the receiving unit 472. + Signal and cos － The differential signal after the signals are synthesized.

[0102] Furthermore, the receiving unit 472 calculates the rotation angle (in other words, the rotation position) of the first target 22 based on each conversion signal obtained, for example, by calculating the inverse tangent function using these conversion signals. In addition, the relationship between the electrical angle θ in the electrical signal of each receiving coil 34, 35 and the rotation angle (that is, the mechanical angle) of the first target 22 is predetermined, for example, based on the size of the first target 22 and the receiving coils 34, 35. Therefore, the rotation angle of the first target 22 can be calculated based on the electrical angle θ. For example, in the present embodiment, the relationship between the electrical angle θ and the mechanical angle is the same in any of the receiving coil groups 301a, 302a, 303a, and 304a.

[0103] In addition, similarly to the above, the receiving unit 472 performs demodulation and AD conversion on the coil output, thereby obtaining a conversion signal based on the output from the first other receiving coil 36 and a conversion signal based on the output from the second other receiving coil 37. And, similarly to the calculation of the rotation angle of the first one target 22 described above, the receiving unit 472 calculates the rotation angle (in other words, the rotation position) of the first other target 23 based on each of the obtained conversion signals.

[0104] Furthermore, the receiving unit 472 determines the rotation position of the rotating member 20 based on the rotation positions of the first one-side target 22 and the first other-side target 23. For example, the average value of the rotation positions of the first one-side target 22 and the first other-side target 23 may be set as the rotation position of the rotating member 20. Alternatively, one of the rotation positions of the first one-side target 22 and the first other-side target 23 may be preferentially used, and as long as the rotation position of the one is not an abnormal value, the rotation position of the one may be set as the rotation position of the rotating member 20.

[0105] In addition, the rotational position of the rotating member 20 may be calculated instead of calculating the rotational positions of the first one target 22 and the first other target 23. For example, the rotational position of the rotating member 20 may be calculated based on a total value obtained by summing up the voltage values ​​of the detection signals (e.g., the above-mentioned conversion signals) from the first receiving coils 34 and 36 and a total value obtained by summing up the voltage values ​​of the detection signals from the second receiving coils 35 and 37.

[0106] When calculating or determining the rotational position of the rotating member 20 based on the detection signals from the first and second receiving coils 34 , 36 , 35 , 37 , the receiving unit 472 outputs a signal indicating the rotational position of the rotating member 20 to the external electronic control device 72 via the first terminal 49 .

[0107] The above is the basic operation of the first signal processing unit 47. In addition, the second signal processing unit 48 also has an oscillating unit 481 and a receiving unit 482 similarly to the first signal processing unit 47. The oscillating unit 481 of the second signal processing unit 48 is the same as the oscillating unit 471 of the first signal processing unit 47, and the receiving unit 482 of the second signal processing unit 48 is the same as the receiving unit 472 of the first signal processing unit 47. The operation of the second signal processing unit 48 is the same as the operation of the first signal processing unit 47, so the description of the operation of the second signal processing unit 48 is omitted.

[0108] Next, the first voltage value V1 of the first receiving coil 34 and the second voltage value V2 of the second receiving coil 35 when the rotating member 20 rotates will be described.

[0109] For example, when an alternating current of a predetermined frequency is applied to the first transmitting coil 31, a magnetic field is generated in the axial direction Da of the components passing through the first receiving coil 34 and the second receiving coil 35. In addition, since the magnetic field changes due to the passage of the alternating current, an induced electromotive force is generated in each of the first receiving coil 34 and the second receiving coil 35 by electromagnetic induction.

[0110] Furthermore, when the first target 22 is opposed to the first transmitting coil 31, the first receiving coil 34, and the second receiving coil 35, an eddy current is generated in the first target 22 and a magnetic field caused by the eddy current is generated. Therefore, among the magnetic fields in the axial direction Da of the components passing through the first receiving coil 34 and the second receiving coil 35, the magnetic field passing through the portion opposed to the first target 22 is offset by the magnetic field caused by the eddy current.

[0111] Also, as the rotating member 20 rotates, in each of the first one receiving coil 34 and the second one receiving coil 35, the position and size of the portion facing the first one target 22 change. Therefore, as the rotating member 20 rotates, the first voltage value V1 generated in the first one receiving coil 34 and the second voltage value V2 generated in the second one receiving coil 35 change periodically. In the present embodiment, for example, as Fig. 9 shown, the first voltage value V1 generated in the first one receiving coil 34 is in a sine wave shape, and the second voltage value V2 generated in the second one receiving coil 35 becomes a cosine wave shape having the same wavelength as the first voltage value V1.

[0112] In addition, since the voltage values generated in the receiving coils 36, 37, 40 to 43 other than the first one receiving coil 34 and the second one receiving coil 35 are the same as those described above, the description thereof is omitted.

[0113] As Fig.10 shown, let the width of the first one receiving area 301 on the circumferential direction Dc of the member be w1. In addition, let the width of the first one target 22 on the circumferential direction Dc of the member be w2. In addition, let a prescribed reference width be w3, and the width w2 is set to be smaller than the reference width w3. When M is a natural number and N is an integer larger than M, the reference width w3 is set to w3 = M / N × w1. Specifically, M is set to an integer of 1 or more and 3 or less, N is set to N = 4, then (M - 1) / 4 × w1 < w2 < w3. In the present embodiment, M is set to 2. That is, the reference width w3 is set to w1 / 2, and w1 / 4 < w2 < w1 / 2.

[0114] In addition, the widths w1, w2, and the reference width w3 are set to the widths at the same position in the radial direction Dr of the member. That is, when the width of the first one receiving area 301 in the cross section along the Figure 1 X-X line shown is w1, let the width of the first one target 22 in the same cross section be w2, and the reference width w3 is set based on this width w1. In addition, for example, imagine a cross section passing through the inner peripheral portion near the rotation axis CL in the radial direction Dr of the member and along the circumferential direction Dc of the first one receiving area 301. When setting the width w1 in this cross section, let the width of the first one target 22 in this cross section be w2. In addition, for example, imagine a cross section passing through the outer peripheral portion far from the rotation axis CL in the radial direction Dr of the member and along the circumferential direction Dc of the first one receiving area 301. When setting the width w1 in this cross section, let the width of the first one target 22 in this cross section be w2.

[0115] The design value of width w2 is set as described above based on the design value of width w1, but deviations may occur in the size and configuration of the first side receiving area 301, the first side target 22, etc. during the manufacturing process of the position detection device 1. In the design of the position detection device 1, the width w2 may be set in consideration of such deviations or may be set without considering the deviations.

[0116] In the position detection device 1, the amplitude of the sin signal is increased by allowing the magnetic flux from the first target 22 to pass through only one of the first and second vortex-shaped portions 34a and 34b. Similarly, the amplitude of the cos signal is increased by allowing the magnetic flux from the first target 22 to pass through only one of the first and second vortex-shaped portions 35a and 35b.

[0117] In order to increase the amplitude of the signal, for example, it can be considered to set w2=w1 / 2. However, the magnetic flux generated from the first target 22 is not only toward the axial direction Da of the component, but also from the first target 22 toward the outside of the circumferential direction Dc of the component. Therefore, in the structure where w2=w1 / 2 is set, for example, when the first target 22 is opposite to the vortex-shaped parts 34b and 35a, the magnetic flux from the first target 22 also enters the vortex-shaped parts 34a and 35b, and the amplitude of the sin signal and the cos signal becomes smaller. That is, if it is set to w2=w3, then Fig.10 As shown, the magnetic flux generated from the first target 22 is directed toward the component axial direction Da as indicated by arrow A1, and also toward the vortex-shaped portions 34a and 35b as indicated by arrow A2. Fig.10 In FIG. 1 , a part of the outer shape of the first target 22 when w2=w3 is indicated by a two-dot chain line.

[0118] In contrast, in the present embodiment, the width w2 is set smaller than w1 / 2, and when the first target 22 is opposed to only one of the first and second vortex-shaped portions 34a and 34b, the magnetic flux entering the other is reduced. Fig.10 As shown, when the first target 22 is opposed to the vortex-shaped parts 34b and 35a, the magnetic flux from the first target 22 is directed toward the outside of the component circumferential direction Dc as indicated by arrow A3. However, since the width w2 is set to be smaller than w1 / 2, the magnetic flux entering the vortex-shaped parts 34a and 35b is reduced compared to the case where w2=w1 / 2. In addition, when the first target 22 is opposed to only one of the first and second vortex-shaped parts 35a and 35b, the magnetic flux entering the other side is reduced. For example, when the first target 22 is opposed to the vortex-shaped parts 34b and 35a, the magnetic flux entering the vortex-shaped parts 34a and 35b from the first target 22 is reduced. As a result, the amplitudes of the sin signal and the cos signal become larger, and the S / N ratio is improved.

[0119] In addition, if the width w2 is made too small, the magnetic flux passing through the vortex-shaped portions 34a, 34b, 35a, and 35b opposite to the first one-side target 22 is reduced, and the S / N ratio is reduced. Therefore, it is preferable to set the width w2 to be larger to some extent. Specifically, it is preferable to set the width w2 so that a state can be formed in which the first one-side target 22 covers the entirety of one of the first and second vortex-shaped portions 34a and 34b. In addition, it is preferable to set the width w2 so that a state can be formed in which the first one-side target 22 covers the entirety of one of the first and second vortex-shaped portions 35a and 35b. Therefore, for example, it is preferable to set it to w1 / 4 <w2。

[0120] The same is true for the targets 23 to 25 and the receiving coils 36, 37, and 40 to 43. That is, by setting the width of the first other target 23 in the component circumferential direction Dc to be larger than 1 / 4 and smaller than 1 / 2 of the width of the first other receiving region 302, the amplitude of the sin signal and cos signal output from the receiving coils 36 and 37 increases, and the S / N ratio improves. In addition, by setting the width of the second one target 24 in the component circumferential direction Dc to be larger than 1 / 4 and smaller than 1 / 2 of the width of the second one receiving region 303, the amplitude of the sin signal and cos signal output from the receiving coils 40 and 41 increases, and the S / N ratio improves. Furthermore, by setting the width of the second other target 25 in the component circumferential direction Dc to be larger than 1 / 4 and smaller than 1 / 2 of the width of the second other receiving region 305 , the amplitudes of the sin and cos signals output from the receiving coils 42 and 43 increase, thereby improving the S / N ratio.

[0121] (Second embodiment)

[0122] Next, the second embodiment will be described. In this embodiment, the differences from the first embodiment will be mainly described. In addition, the same or equivalent parts as those in the above embodiment will be omitted or simplified. This also applies to the description of the embodiments described later.

[0123] like Fig.11 As shown, in this embodiment, the reference width W3 is set to w3=3 / 4×w1, w1 / 2 <w2<w3。

[0124] In order to increase the amplitude of the sin signal and the cos signal, for example, the width w2 can be considered to be 3 / 4×w1. That is, when the one end edge 221 reaches the one side end position of the operating range W1a, the magnetic flux from the first target 22 passes through both the first and second vortex-shaped parts 34a and 34b. In addition, with respect to the second receiving coil 35, it can be considered that the magnetic flux from the first target 22 only passes through the first vortex-shaped part 35a, so that the amplitude of the cos signal becomes larger. In addition, when the other end edge 222 reaches the other side end position of the operating range W1a, the magnetic flux from the first target 22 passes through both the first and second vortex-shaped parts 35a and 35b. In addition, with respect to the first receiving coil 34, it can be considered that the magnetic flux from the first target 22 only passes through the second vortex-shaped part 34b, so that the amplitude of the sin signal becomes larger.

[0125] However, the magnetic flux generated from the first target 22 is directed not only toward the component axial direction Da, but also toward the outside of the component circumferential direction Dc. Therefore, in the structure set as w2=3 / 4×w1, when the one end edge 221 reaches the one side end position of the operating range W1a, the magnetic flux from the first target 22 also enters the second vortex-shaped portion 35b, and the amplitude of the cos signal decreases. In addition, when the other end edge 222 reaches the other side end position of the operating range W1a, the magnetic flux from the first target 22 also enters the first vortex-shaped portion 34a, and the amplitude of the sin signal decreases.

[0126] In contrast, in the present embodiment, the width w2 is set to be smaller than 3 / 4×w1, and when the one end edge 221 reaches the one side end position of the operating range W1a, the magnetic flux entering the second vortex-shaped portion 35b decreases. In addition, when the other end edge 222 reaches the other side end position of the operating range W1a, the magnetic flux entering the first vortex-shaped portion 34a decreases. As a result, the amplitudes of the sin signal and the cos signal increase, and the S / N ratio improves.

[0127] The same is true for the targets 23 to 25 and the receiving coils 36, 37, 40 to 43. That is, by setting the width of the first other target 23 in the component circumferential direction Dc to be larger than 1 / 2 and smaller than 3 / 4 of the width of the first other receiving region 302, the amplitude of the sin signal and cos signal output from the receiving coils 36 and 37 becomes larger, and the S / N ratio is improved. In addition, by setting the width of the second one target 24 in the component circumferential direction Dc to be larger than 1 / 2 and smaller than 3 / 4 of the width of the second one receiving region 303, the amplitude of the sin signal and cos signal output from the receiving coils 40 and 41 becomes larger, and the S / N ratio is improved. Furthermore, by setting the width of the second other target 25 in the component circumferential direction Dc to be larger than 1 / 2 and smaller than 3 / 4 of the width of the second other receiving region 305 , the amplitudes of the sin and cos signals output from the receiving coils 42 and 43 increase, thereby improving the S / N ratio.

[0128] Except for the above-described matters, the present embodiment is the same as the first embodiment. Also, in the present embodiment, similarly to the first embodiment, the effects achieved by the configuration common to the first embodiment described above can be obtained.

[0129] (Third embodiment)

[0130] Next, a third embodiment will be described. In this embodiment, points different from the above-mentioned first embodiment will be mainly described.

[0131] like Fig.12 As shown in FIG. 1 , in this embodiment, the pattern shape of the receiving coils 34 to 37 and 40 to 43 is different from that of the first embodiment. Therefore, in this embodiment, the spiral portions 34a to 43b (see FIG. 1 ) of the first embodiment are not provided. Figure 5 ).

[0132] In addition, in this embodiment, as in the first embodiment, when viewed in the direction of the component axial direction Da, all the receiving coils 34 to 37, 40 to 43 are arranged inside the first transmitting coil 31 and inside the second transmitting coil 32. And, each of the receiving coils 34 to 37, 40 to 43 is configured by appropriately connecting different wiring layers through the via hole 30d so as not to interfere with each other (that is, not to overlap).

[0133] In the present embodiment, each receiving coil 34 to 37, 40 to 43 is formed by connecting two adjacent wiring layers in the sequentially stacked wiring layers with a via 30d. For example, in the present embodiment, each receiving coil 34 to 37, 40 to 43 is formed by connecting the outermost wiring layer located on the other surface 30b side of the substrate 30 to the wiring layer of the next layer as the outermost layer. Fig.12In the display of each receiving coil 34 to 37, 40 to 43, the wiring layer formed on the outermost layer of the substrate 30 is indicated by a solid line, and the wiring layer formed on the next layer of the outermost layer is indicated by a dotted line. In addition, the transmitting coils 31 and 32 are all indicated by solid lines.

[0134] Specifically, the first receiving coil 34 has a first wavy portion 34d and a second wavy portion 34e. When viewed in the direction of the component axial direction Da, the first and second wavy portions 34d and 34e are each in a pattern shape depicting a sine curve. Furthermore, the first and second wavy portions 34d and 34e are connected in series, for example, via a connection wiring pattern to form a closed loop.

[0135] In addition, the second receiving coil 35 has a first wavy portion 35d and a second wavy portion 35e. When viewed in the direction of the component axial direction Da, the first and second wavy portions 35d and 35e respectively form a pattern shape depicting a cosine curve. And, the first and second wavy portions 35d and 35e are connected in series, for example, via a connecting wiring pattern to form a closed loop. For example, the wavy portions 34d, 34e, 35d, and 35e of the first and second receiving coils 34 and 35 are arranged in a manner that overlaps on one side of the component axial direction Da relative to the first target 22 at any position within the operating range W1a of the first target 22.

[0136] The same is true for the other receiving coil groups 302a, 303a, and 304a other than the first one receiving coil group 301a including the above-mentioned receiving coils 34 and 35. That is, when viewed in the direction of the component axial direction Da, the first other receiving coil 36 has a first wavy portion 36d and a second wavy portion 36e that are connected in series to each other in a pattern shape that depicts a sine curve. In addition, when viewed in the direction of the component axial direction Da, the second other receiving coil 37 has a first wavy portion 37d and a second wavy portion 37e that are connected in series to each other in a pattern shape that depicts a cosine curve. For example, the wavy portions 36d, 36e, 37d, and 37e of the first and second other receiving coils 36 and 37 are arranged so as to overlap with each other on one side of the component axial direction Da at any position within the operating range W1b of the first other target 23.

[0137] In addition, when viewed in the direction of the component axis Da, the third first receiving coil 40 has a pattern shape depicting a sine curve and the first wavy portion 40d and the second wavy portion 40e that are connected in series with each other. In addition, when viewed in the direction of the component axis Da, the fourth first receiving coil 41 has a pattern shape depicting a cosine curve and the first wavy portion 41d and the second wavy portion 41e that are connected in series with each other. For example, the wavy portions 40d, 40e, 41d, and 41e of the third and fourth first receiving coils 40 and 41 are arranged so as to overlap the second first target 24 on one side in the component axis Da at any position within the operation range W2a of the second first target 24.

[0138] In addition, when viewed in the direction of the component axis Da, the third second receiving coil 42 has a pattern shape depicting a sine curve and the first wavy portion 42d and the second wavy portion 42e that are connected in series with each other. In addition, when viewed in the direction of the component axis Da, the fourth second receiving coil 43 has a pattern shape depicting a cosine curve and the first wavy portion 43d and the second wavy portion 43e that are connected in series with each other. For example, the wavy portions 42d, 42e, 43d, and 43e of the third and fourth second receiving coils 42 and 43 are arranged so as to overlap the second second target 25 on one side in the component axis Da at any position within the operation range W2b of the second second target 25.

[0139] In addition, in the present embodiment, the circumferential one-end position P1 of the first first receiving region 301 coincides with the one-side end position of the second first receiving coil 35 on the component circumferential direction Dc. And the circumferential other-end position P2 of the first first receiving region 301 coincides with the other-side end position of the second first receiving coil 35 on the component circumferential direction Dc. The same applies to the first second receiving region 302, the second first receiving region 303, and the second second receiving region 304.

[0140] In this way, in the structure where the receiving coils 34 and 35 have the wavy portions 34d, 34e, 35d, and 35e, by allowing the magnetic flux from the first first target 22 to pass through, for example, only an amount equivalent to half a cycle of the wavy portions 34d, 34e, 35d, and 35e, the amplitudes of the sin signal and the cos signal increase. In the present embodiment, since it is set as w1 / 4 < w2 < w1 / 2 as in the first embodiment, by allowing the magnetic flux to pass through as described above, the signal amplitude can be increased and the S / N ratio can be improved. The same applies to the targets 23 to 25 and the receiving coils 36, 37, 40 to 43.

[0141] Except for the above description, this embodiment is the same as the first embodiment. Also, in this embodiment, similarly to the first embodiment, the effects achieved by the configuration common to the first embodiment described above can be obtained.

[0142] (Fourth embodiment)

[0143] Next, a fourth embodiment will be described. In this embodiment, points different from the above-described first embodiment will be mainly described.

[0144] like Fig.13 As shown, the substrate 30 of this embodiment has two first transmitting coils 311 and 312 instead of the first transmitting coil 31 of the first embodiment (see Figure 5 ), having two second transmitting coils 321, 322 instead of the second transmitting coil 32 of the first embodiment (refer to Figure 5 ).

[0145] The two first transmission coils 311 and 312 are a first one transmission coil 311 and a first other transmission coil 312 . The two second transmission coils 321 and 322 are a second one transmission coil 321 and a second other transmission coil 322 .

[0146] Furthermore, when viewed in the direction of the component axial direction Da, the first and second one-side receiving coils 34 and 35 are arranged inside the first one-side transmitting coil 311, while the other receiving coils 36, 37, 40 to 43 are arranged outside the first one-side transmitting coil 311. Therefore, when an alternating current flows through the first one-side transmitting coil 311, an induced current flows through the first and second one-side receiving coils 34 and 35 by electromagnetic induction generated by energizing the first one-side transmitting coil 311. When viewed in the direction of the component axial direction Da, the first one-side transmitting coil 311 is formed in a fan ring shape along the outer periphery of the first one-side receiving region 301.

[0147] Furthermore, when viewed in the direction of the component axial direction Da, the first and second other receiving coils 36 and 37 are arranged inside the first other transmitting coil 312, while the other receiving coils 34, 35, 40 to 43 are arranged outside the first other transmitting coil 312. Therefore, when an alternating current flows through the first other transmitting coil 312, an induced current flows through the first and second other receiving coils 36 and 37 by electromagnetic induction generated by energizing the first other transmitting coil 312. When viewed in the direction of the component axial direction Da, the first other transmitting coil 312 is formed in a fan ring shape along the outer periphery of the first other receiving region 302.

[0148] In addition, when viewed in the direction of the component axial direction Da, the third and fourth one-side receiving coils 40 and 41 are arranged inside the second one-side transmitting coil 321, while the other receiving coils 34 to 37, 42, and 43 are arranged outside the second one-side transmitting coil 321. Therefore, when an alternating current flows through the second one-side transmitting coil 321, an induced current flows through the third and fourth one-side receiving coils 40 and 41 by electromagnetic induction generated by energizing the second one-side transmitting coil 321. When viewed in the direction of the component axial direction Da, the second one-side transmitting coil 321 is formed in a fan ring shape along the outer periphery of the second one-side receiving region 303.

[0149] Furthermore, when viewed in the direction of the component axial direction Da, the third and fourth other receiving coils 42 and 43 are arranged inside the second other transmitting coil 322, while the other receiving coils 34 to 37, 40, and 41 are arranged outside the second other transmitting coil 322. Therefore, when an alternating current flows through the second other transmitting coil 322, an induced current flows through the third and fourth other receiving coils 42 and 43 by electromagnetic induction generated by energizing the second other transmitting coil 322. When viewed in the direction of the component axial direction Da, the second other transmitting coil 322 is formed in a fan ring shape along the outer periphery of the second other receiving region 304.

[0150] Furthermore, the plurality of transmitting coils 311, 312, 321, 322 are arranged in the order of the first transmitting coil 311, the second transmitting coil 322, the first transmitting coil 312, and the second transmitting coil 321 from one side to the other side of the component circumferential direction Dc. In addition, the plurality of transmitting coils 311, 312, 321, 322 are arranged at intervals from each other. These transmitting coils 311, 312, 321, 322 are in the shape of a ring as a whole with the rotation axis CL as the center.

[0151] Except for the above description, the first transmitting coil 311 and the first other transmitting coil 312 are the same as the first transmitting coil 31 of the first embodiment, and the second transmitting coil 321 and the second other transmitting coil 322 are the same as the second transmitting coil 32 of the first embodiment.

[0152] With the configuration of the transmitting coils 311 , 312 , 321 , and 322 described above, it is possible to generate electromagnetic induction to the receiving coils in each of the receiving coil groups 301 a , 302 a , 303 a , and 304 a .

[0153] In the present embodiment, the transmission coils 311 , 312 , 321 , and 322 may be formed on the same wiring layer in the substrate 30 .

[0154] Except for the above description, this embodiment is the same as the first embodiment. Also, in this embodiment, similarly to the first embodiment, the effects achieved by the configuration common to the first embodiment described above can be obtained.

[0155] (Fifth embodiment)

[0156] Next, a fifth embodiment will be described. In this embodiment, points different from the third embodiment described above will be mainly described.

[0157] like Fig.14 As shown, the substrate 30 of this embodiment has two first transmitting coils 311 and 312 similar to those of the fourth embodiment, instead of the first transmitting coil 31 of the third embodiment (see Fig.12 ). In addition, the substrate 30 has two second transmission coils 321 and 322 similar to the fourth embodiment, instead of the second transmission coil 32 of the third embodiment (see Fig.12 ).

[0158] Except for the above description, this embodiment is the same as the third embodiment. Also, in this embodiment, similarly to the third embodiment, the effects achieved by the configuration common to the third embodiment described above can be obtained.

[0159] (Other embodiments)

[0160] (1) In the above-mentioned embodiments, the position detection device 1 is used to detect the rotational position of a brake pedal or an accelerator pedal for a vehicle, but the use of the position detection device 1 is not limited thereto and various assumptions are made. In addition, the position detection device 1 may also be used for purposes other than vehicles.

[0161] (2) In each of the above embodiments, for example Figure 1 As shown, the moving direction of the targets 22 to 25 is the component circumferential direction Dc, but this is only an example. For example, the targets 22 to 25 may reciprocate linearly, and the position detection device 1 may detect the position of the targets 22 to 25 in the moving direction.

[0162] (3) In each of the above embodiments, if Figure 1 As shown, all four targets 22 to 25 have the same fan-shaped shape, but this is only an example. The shapes of the targets 22 to 25 may not be fan-shaped, and the shapes of the targets 22 to 25 may be different from each other.

[0163] (4) In each of the above embodiments, for example Figure 1As shown, the rotating member 20 has two first targets 22 and 23, but it is also conceivable that only one of the two first targets 22 and 23 is provided and the other is not. Similarly, it is also conceivable that the rotating member 20 has only one of the two second targets 24 and 25 and not the other. Further, the number of the first targets 22 and 23 may be three or more, and the number of the second targets 24 and 25 may be three or more.

[0164] (5) In each of the above-described embodiments, as Figure 8 shown, the position detection device 1 includes, as a circuit, an independent first system 305 and a second system 306, but it may also include three or more systems having an independent structure as a circuit. In addition, the position detection device 1 may include only one of the first system 305 and the second system 306.

[0165] (6) A plurality of receiving coil groups 301a to 304a may be arranged in each of the receiving regions 301 to 304. For example, two receiving coil groups 301a may be arranged in the first one-sided receiving region 301 in a manner of being arranged in the circumferential direction Dc of the member. In this case, two first one-sided targets 22 are arranged at the same central angle with a pitch of 45 degrees. And, let the total value of the widths of the two first one-sided targets 22 be w2, and (M - 1) / 4×w1 < w2 < w3.

[0166] (7) In the first and fourth embodiments, it may be set that 0 < w2 < w1 / 4. Even in such a structure, when the first one-sided target 22 faces only one of the first and second spiral portions 34a and 34b, the magnetic flux entering the other is reduced. In addition, when the first one-sided target 22 faces only one of the first and second spiral portions 35a and 35b, the magnetic flux entering the other is reduced. Thereby, the amplitudes of the sin signal and the cos signal become larger, and the S / N ratio is improved.

[0167] (8) In addition, the present disclosure is not limited to the above-described embodiments, and various modifications can be made for implementation. Moreover, the above-described embodiments are not independent of each other, and can be appropriately combined except in cases where obvious combinations are not possible. For example, the second embodiment can be combined with the third to fifth embodiments.

[0168] In addition, in the above-mentioned embodiments, the elements constituting the embodiments are not necessarily required, except for the cases where they are specifically indicated as required and the cases where they are obviously required in principle. In addition, in the above-mentioned embodiments, when referring to the number, value, amount, range, etc. of the constituent elements of the embodiments, except for the cases where they are specifically indicated as required and the cases where they are obviously limited to a specific number in principle, they are not limited to the specific number. In addition, in the above-mentioned embodiments, when referring to the material, shape, positional relationship, etc. of the constituent elements, except for the cases where they are specifically indicated and the cases where they are limited to a specific material, shape, positional relationship, etc. in principle, they are not limited to the material, shape, positional relationship, etc.

Claims

1. A position detection device, have: substrate(30); The transmitting coils (31, 32) are arranged on the substrate and generate a magnetic field by supplying an alternating current; The targets (22, 23, 24, 25) are arranged to face the substrate and move in a predetermined moving direction (Dc), and eddy currents flow through the magnetic field to generate a magnetic field that cancels out the magnetic field; and A plurality of receiving coils (34, 35, 36, 37, 40, 41, 42, 43) are arranged in the substrate in the moving direction to receive the magnetic field generated by the transmitting coil. The area occupied by the plurality of receiving coils in the substrate is defined as a receiving area (301, 302, 303, 304). Assume that the width of the receiving area in the moving direction is w1, Assume that the width of the target in the moving direction is w2, Let M be an integer greater than or equal to 1 and less than or equal to 3, Assume the base width is w3 = M / 4 × w1, So that (M-1) / 4×w1 <w2<w3。 2. The position detection device according to claim 1, The receiving coil includes a spiral portion (34a, 34b, 35a, 35b, 36a, 36b, 37a, 37b, 40a, 40b, 41a, 41b, 42a, 42b, 43a, 43b).

3. The position detection device according to claim 1, The receiving coil includes a wave-shaped portion (34d, 34e, 35d, 35e, 36d, 36e, 37d, 37e, 40d, 40e, 41d, 41e, 42d, 42e, 43d, 43e), M＝2。 4. The position detection device according to any one of claims 1 to 3, wherein the substrate is in the shape of a disk. The receiving region is a sector ring-shaped region which is a part of the substrate, and the transmitting coil is arranged in a sector ring shape along the outer circumference of the receiving region.

5. The position detection device according to any one of claims 1 to 3, The substrate is in the shape of a disk. The transmitting coil is arranged in a ring shape along a circumferential direction (Dc) of the substrate.

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