Angle sensor

Abstract

An angle sensor (1) comprises: a cylinder (10) including a plurality of pillars (20) extending in a radial direction; and a plurality of outer coils (30) and a plurality of inner coils (40) wound around the plurality of pillars (20). The outer coils (30) are each provided with one end portion (31) and another end portion (32) in the circumferential direction. Furthermore, the inner coils (40) are each provided with one end portion (41) and another end portion (42) in the circumferential direction. The plurality of outer coils (30) and the plurality of inner coils (40) are separated in the radial direction.

Description

Angle Sensor

[0001] The present invention relates to an angle sensor, and more particularly to an inductive angle sensor.

[0002] Conventionally, various sensors have been used to detect the rotation angle of a motor, etc. An inductive sensor is one of such angle sensors for detecting the rotation angle (see, for example, Patent Document 1).

[0003] JP 2017-67600 A

[0004] Conventional inductive sensors have room for improvement in terms of detection accuracy.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an angle sensor that can improve detection accuracy.

[0006] An angle sensor according to one aspect of the present invention comprises a tube having a plurality of pillars extending radially, and a plurality of outer coils and a plurality of inner coils wound around the plurality of pillars, wherein the outer coil has one end and the other end in the circumferential direction, and the inner coil has one end and the other end in the circumferential direction, and the plurality of outer coils and the plurality of inner coils are spaced apart in the radial direction.

[0007] 12 is a diagram schematically illustrating the configuration of an angle sensor according to an embodiment of the present invention, and is a partially transparent perspective view schematically illustrating the internal configuration through the penetration of some members of the angle sensor. FIG. 13 is a perspective view schematically illustrating the angle sensor. FIG. 14 is a front view schematically illustrating the angle sensor. FIG. 15 is a side view schematically illustrating the angle sensor. FIG. 16 is a perspective view schematically illustrating the configuration of a cylinder, a plurality of outer coils, and a plurality of inner coils included in the angle sensor. FIG. 17 is a perspective view schematically illustrating the configuration of a cylinder, a plurality of outer coils, and a plurality of inner coils included in the angle sensor. FIG. 18 is a side view schematically illustrating the configuration of a cylinder. FIG. 19 is a front view schematically illustrating the configuration of a cylinder. FIG. 19 is a diagram showing one side of a cylinder cut along a plane including an axis. FIG. 19 is a perspective view showing an example of an outer coil structure formed by a plurality of outer coils, and an inner coil structure formed by a plurality of inner coils. FIG. 19 is a front view schematically illustrating an example of an outer coil structure formed by a plurality of outer coils, and an inner coil structure formed by a plurality of inner coils. FIG. 19 is a diagram schematically illustrating the configuration of the outer coil structure and the inner coil structure shown in FIGS. 10 and 11. FIG. 19 is a perspective view schematically illustrating the configuration of a frame. FIG. 20 is a rear view schematically illustrating the configuration of the frame. Fig. 18 is a cross-sectional view showing a stator in an assembled state in which the cylinder is fixed to the frame and the cylinder and frame are assembled. Fig. 19 is a partial cross-sectional view partially showing a cross section taken along a plane including the axis of an angle sensor according to a modified example. Fig. 19 is a perspective view of a cylinder according to a modified example. Fig. 20 is a cross-sectional view partially showing a cross section taken along a plane including the axis of a cylinder according to a modified example. Fig. 21 is a partially enlarged cross-sectional view of Fig. 18 .

[0008] An embodiment of the present invention will be described below with reference to the accompanying drawings. Note that in the drawings, not all of the components are designated by reference numerals, and some of the components may be omitted. FIG. 1 is a diagram schematically illustrating the configuration of an angle sensor 1 according to an embodiment of the present invention, and is a partially transparent perspective view showing the internal configuration of the angle sensor 1 through some of its components. FIG. 2 is a perspective view schematically illustrating the angle sensor 1, FIG. 3 is a front view schematically illustrating the angle sensor 1, and FIG. 4 is a side view schematically illustrating the angle sensor 1. FIGS. 5 and 6 are perspective views schematically illustrating the configuration of a tube 10, multiple outer coils 30, and multiple inner coils 40 included in the angle sensor 1. As shown in FIGS. 1 to 6, the angle sensor 1 includes a tube 10 having multiple pillars 20 extending radially, and multiple outer coils 30 and multiple inner coils 40 wound around the multiple pillars 20. In the circumferential direction, the outer coil 30 has one end 31 and the other end 32. In addition, in the circumferential direction, the inner coil 40 has one end 41 and the other end 42. The multiple outer coils 30 and the multiple inner coils 40 are spaced apart in the radial direction. The configuration of the angle sensor 1 will be described in detail below. Note that Figures 5 and 6 are perspective views of the cylinder 10 viewed from one side and the other side in the direction of the axis x, respectively. The axis x is the axis of rotation of the angle sensor 1. The radial direction is the direction perpendicular to the axis x, and the circumferential direction is the direction around the axis x.

[0009] Specifically, as shown in, for example, Figures 1 to 4, the angle sensor 1 includes a rotor 2, which is a rotating body, and a stator 3. The rotor 2 includes a cylinder 50 and a plurality of conductors 6 fixed to the cylinder 50. The stator 3 includes the cylinder 10 described above. As shown in Figures 2 to 4, in the angle sensor 1, the rotor 2 is disposed inside the stator 3, and the rotor 2 and the stator 3 face each other in the radial direction of the cylinder 10. Note that Figures 2 to 4 show the rotor 2 and the stator 3 in a predetermined positional relationship. This predetermined positional relationship is an example of the positional relationship between the rotor 2 and the stator 3 when the angle sensor 1 is attached to an application object and in use.

[0010] As shown in FIGS. 1 to 4 , the cylinder 50 of the rotor 2 is a cylindrical member extending along the axis x. Note that FIG. 1 shows the interior of the cylinder 50 in a see-through manner. The cylinder 50 of the rotor 2 is attached to a rotating member of an external device to which the angle sensor 1 is applied, so that the axis x coincides or substantially coincides with the rotation axis of the rotating member of the external device. For example, as shown in FIGS. 1 to 4 , the cylinder 50 of the rotor 2 has an inner circumferential surface 51, which is a cylindrical surface extending along a cylindrical surface with the axis x as its central axis, and an outer circumferential surface 52, which is a cylindrical surface facing away from the inner circumferential surface 51 on the radially outer side (hereinafter also referred to as the "outer peripheral side"). The cylinder 50 also has end faces 53 and 54, which are surfaces facing in the respective directions in which the axis x extends. The inner circumferential surface 51 and the outer circumferential surface 52 extend between the end faces 53 and 54. The angle sensor 1 is applied to, for example, a motor, and the motor shaft passes through the inner peripheral surface 51 of the cylinder 50 of the rotor 2, and the rotor 2 is fixed to the shaft. The cylinder 50 is made of, for example, a resin material, a non-magnetic material, a non-conductive material, etc. The non-magnetic material may be non-conductive.

[0011] As shown in FIG. 1 , the tube 50 has a conductor structure 4. The conductor structure 4 is fixed to the tube 50. The conductor structure 4 is formed of conductors, and for example, as shown in FIG. 1 , the conductor structure 4 is composed of a plurality of conductors 5. The plurality of conductors 5 are, for example, arranged in a circumferential direction around the axis x. As shown schematically in FIG. 1 , the plurality of conductors 5 form a cylindrical conductor structure 4 extending in a ring shape around the axis x. The conductors 5 may be any conductive material (a material capable of generating so-called eddy currents or induced currents (currents) within one surface), such as metal bodies 5. Hereinafter, as an example, the angle sensor 1 is assumed to have metal bodies 5 as the conductors 5. The plurality of metal bodies 5 are arranged at predetermined distances in the circumferential direction of the tube 50. In other words, two adjacent metal bodies 5 are separated by a predetermined distance around the axis x. The plurality of conductors 5 are arranged at equal or approximately equal angular intervals in the circumferential direction along a cylindrical surface having the axis x as its central axis. The multiple metal bodies 5 have, for example, a curved shape. The multiple metal bodies 5 may be connected to one another. The multiple metal bodies 5 are connected by one or more connecting parts, and the one or more connecting parts may be formed of a non-conductive material (e.g., resin) or a conductive material (e.g., metal), and the multiple metal bodies 5 may be electrically connected.

[0012] The plurality of metal bodies 5 are provided in a tube 50, for example, as shown in Fig. 1 . The entire metal bodies 5 may be embedded in the tube 50, or a portion of each metal body 5 may be exposed on the surface of the tube 50. The plurality of metal bodies 5 may also be attached to the surface of the tube 50, for example, to the outer peripheral surface 52. In this case, a portion of the metal body 5 may be embedded in the tube 50.

[0013] As shown in Figures 1 to 4, the stator 3 has the above-mentioned tube 10 and a frame 60. The frame 60 is a member that supports the tube 10. Figure 7 is a side view showing the schematic configuration of the tube 10, Figure 8 is a front view showing the schematic configuration of the tube 10, and Figure 9 is a diagram showing one side of the tube 10 cut along a plane including the axis x. Note that Figures 7 to 9 show a plurality of outer coils 30 and a plurality of inner coils 40.

[0014] As shown in FIGS. 5 to 8 , the cylinder 10 of the stator 3 is a cylindrical member extending along the axis x and includes, for example, a wall 11 and a base end 12 in addition to a plurality of pillars 20. The wall 11 is a cylindrical portion extending from the base end 12 in the direction of the axis x and includes an outer peripheral surface 11a facing the outer periphery and an inner peripheral surface 11b facing the inner periphery. The outer peripheral surface 11a and the inner peripheral surface 11b are back-to-back facing each other. The wall 11 is shaped, for example, along a cylindrical surface with the axis x as its central axis. The outer peripheral surface 11a extends, for example, on a cylindrical or approximately cylindrical surface with the axis x as its central axis, and the inner peripheral surface 11b extends, for example, on a cylindrical or approximately cylindrical surface with the axis x as its central axis. The base end 12 is a portion extending annularly around the axis x and includes end surfaces 12a and 12b that are annular surfaces facing back-to-back in the direction of the axis x. The base end 12 has an outer peripheral surface 12c and an inner peripheral surface 12d, which are cylindrical surfaces facing each other in the radial direction. The outer peripheral surface 12c extends between the end surfaces 12a and 12b at the outer peripheral end, and the inner peripheral surface 12d extends between the end surfaces 12a and 12b at the inner peripheral end. A groove 12e, which is an annular groove recessed toward the inner peripheral side, is formed in the outer peripheral surface 12c. The outer peripheral surface 12c extends, for example, on a cylindrical surface or a substantially cylindrical surface with the axis x as its central axis. The wall 11 extends from the end surface 12a of the base end 12.

[0015] As shown in Figures 5 to 8, multiple pillars 20 are provided on the wall 11, for example, at equal or approximately equal angular intervals around the axis x. Each pillar 20 protrudes from the wall 11 to the outer and inner circumferential sides, and each pillar 20 has an outer pillar 21 protruding from the wall 11 to the outer circumferential side and an inner pillar 22 protruding from the wall 11 to the inner circumferential side. Specifically, the outer pillar 21 protrudes from the outer circumferential surface 11a of the wall 11 to the outer circumferential side, and the inner pillar 22 protrudes from the inner circumferential surface 11b of the wall 11 to the inner circumferential side. The outer pillar 21 and the inner pillar 22 of each pillar 20 are formed on the wall 11 such that, for example, their respective circumferential centers coincide with each other at angular positions around the axis x.

[0016] As shown in FIGS. 5 to 8 , the outer columns 21 have, for example, a rectangular or approximately rectangular cross section perpendicular to the radial direction. The cross-sectional shape of the outer columns 21 is not limited to a rectangle and may be other shapes. Each outer column 21 has an outer peripheral surface 21a that faces the outer periphery. The outer peripheral surface 21a of each of the multiple outer columns 21 is curved, for example, so as to extend on a cylindrical or approximately cylindrical surface with the axis x as its central axis. As shown in FIGS. 5 , 6 , and 8 , the outer column 21 includes, for example, a connecting portion 21b that connects to the wall 11 and an end portion 21c on the outer periphery. The outer peripheral surface 21a is formed at the end portion 21c. Furthermore, as shown in FIGS. 5 , 6 , and 8 , the end portion 21c protrudes more circumferentially and in the axis x direction than the connecting portion 21b, forming an annular groove between the connecting portion 21b and the wall 11. The outer peripheral surface 12c of the base end portion 12 is not located outer circumferentially of the outer peripheral surfaces 21a of the multiple outer columns 21. For example, the outer peripheral surface 12c of the base end portion 12 extends on a cylindrical surface or a substantially cylindrical surface on which the outer peripheral surfaces 21a of the multiple outer posts 21 extend.

[0017] The inner columns 22 have a shape similar to that of the outer columns 21. As shown in FIGS. 5 to 8 , the inner columns 22 have, for example, a rectangular or approximately rectangular cross section perpendicular to the radial direction. Note that the cross-sectional shape of the inner columns 22 is not limited to a rectangular shape and may be other shapes. Each inner column 22 has an inner circumferential surface 22a that faces the inner circumferential side. The inner circumferential surfaces 22a of the multiple inner columns 22 face the outer circumferential surface 52 of the cylinder 50 of the rotor 2 with an annular gap therebetween. The inner circumferential surface 22a of each of the multiple inner columns 22 is curved, for example, so as to extend on a cylindrical surface or an approximately cylindrical surface with the axis x as the central axis. As shown in FIGS. 5 , 6 , and 8 , the inner column 22 includes, for example, a connecting portion 22b that connects to the wall 11 and an inner circumferential end portion 22c. The inner circumferential surface 22a is formed at the end portion 22c. As shown in FIGS. 5, 6 and 8, the end portion 22c protrudes in the circumferential direction and the direction of the axis x beyond the connecting portion 22b, and an annular groove is formed between the connecting portion 22b and the wall 11.

[0018] The number of the plurality of columns 20, i.e., the number of the plurality of outer columns 21 and the plurality of inner columns 22, is set, for example, according to the outer coil structure 6 formed by the plurality of outer coils 30 and the inner coil structure 7 formed by the plurality of inner coils 40, which will be described later. In this example, the number of the plurality of columns 20, i.e., the number of the plurality of outer columns 21 and the number of inner columns 22, is an even number, and specifically, for example, 16 columns 20, i.e., 16 outer columns 21 and 16 inner columns 22, are provided in the tube 10. As described above, the plurality of columns 20 are provided at equal or approximately equal angular intervals around the axis x, and the plurality of outer columns 21 and the plurality of inner columns 22 are each provided at equal or approximately equal angular intervals around the axis x. Furthermore, for example, as shown in FIG. 8 , in each column 20, two radial lines circumferentially sandwiching the outer column 21 and two radial lines circumferentially sandwiching the inner column 22 coincide or approximately coincide. That is, in each column 20, radial lines r1 and r2 passing through the side ends 21d and 21e, which are both circumferential ends of the outer column 21, pass through the side ends 22d and 22e, which are both circumferential ends of the inner column 22, and the angle between the radial lines sandwiching the side ends 21d and 21e of the outer column 21 (see extension angle α in FIG. 8 ) matches or nearly matches the angle between the radial lines sandwiching the side ends 22d and 22e of the inner column 22 (see extension angle α in FIG. 8 ). In addition, the width of the outer column 21 in the direction of the axis x matches or nearly matches the width of the inner column 22 in the direction of the axis x.

[0019] The tube 10 is, for example, integrally molded from the same material, and each component of the tube 10 is connected together. That is, the wall 11, the base end 12, the multiple outer columns 21, and the multiple inner columns 22 are each parts of the tube 10 integrally formed from the same material and are connected together. The tube 10 is an insulating member, for example, a resin member. The tube 10 is made of, for example, a resin material, a non-magnetic material, a non-conductive material, etc. Note that the non-magnetic material may be non-conductive. Note that any or all of the components of the tube 10 may be formed as separate bodies. In this case, the tube 10 is formed by assembling the components formed as separate bodies by adhesive or the like.

[0020] As described above, a plurality of outer coils 30 and a plurality of inner coils 40 are wound around a plurality of pillars 20 of the tube 10 of the stator 3. The outer coils 30 and the inner coils 40 are spaced apart in the radial direction. Specifically, for example, as shown in FIGS. 5 to 9 , the outer coils 30 are wound around a plurality of outer pillars 21, and the inner coils 40 are wound around a plurality of inner pillars 22. Thus, a wall 11 is interposed between the outer coils 30 and the inner coils 40, and the outer coils 30 and the inner coils 40 are spaced apart in the radial direction. The angle sensor 1 includes, for example, a conductive conductor 33 and a conductive conductor 43. The conductor 33 forms the outer coils 30, and the conductor 43 forms the inner coils 40. The conductors 33 and 43 are coated with, for example, an insulating material (an insulating film or a coating).

[0021] The multiple outer coils 30 are, for example, lined up and connected in the circumferential direction around the axis x. As schematically shown in FIGS. 5 to 11 , the multiple outer coils 30 form a cylindrical shape (hereinafter referred to as the "outer coil structure") 6 extending annularly along the outer peripheral surface 11a of the wall 11 of the tube 10. Note that FIGS. 10 and 11 are a perspective view and a front view, respectively, showing an example of the outer coil structure 6 formed by the multiple outer coils 30 and an example of the inner coil structure 7 formed by the multiple inner coils 40 described below. In FIGS. 10 and 11 , the outer coil structure 6 and the inner coil structure 7 are shown in their positional relationship formed on the tube 10. The outer coil structure 6 is a shape formed by the arrangement of the multiple outer coils 30. In the outer coil structure 6, the multiple outer coils 30 are, for example, lined up annularly around the axis x along a circular surface. The multiple outer coils 30 are, for example, lined up annularly along a cylindrical surface with the axis x as the central axis. Each outer coil 30 has a shape that surrounds a space, for example. Each outer coil 30 has a shape that the space surrounded by each outer coil 30 follows an annular surface around the axis x, for example.

[0022] The outer coil 30 is, for example, a coil formed by winding magnet wire 33, which is an example of a conductive conductor 33. As described above, the multiple outer coils 30 are formed by winding magnet wire 33 around multiple outer columns 21. The multiple outer coils 30 have an annular shape wound around the radial direction of the tube 10 and surround a planar space facing the radial direction. As shown in Figures 5 and 6, the multiple outer coils 30 are formed on the outer peripheral surface 11a side of the wall 11 of the tube 10, connected in series around the axis x, thereby forming the outer coil structure 6 shown in Figures 10 and 11. Note that the conductive conductor 33 forming the outer coil 30 is not limited to magnet wire.

[0023] 12 is a diagram schematically illustrating the configuration of the outer coil structure 6 and the inner coil structure 7 shown in FIGS. 10 and 11. As shown in FIGS. 5, 6, 8, and 12, a magnet wire 33 serving as a conductor 33 is wound radially around each of the multiple outer columns 21, and multiple annular outer coils 30 are formed radially around the multiple outer columns 21, forming an outer coil structure 6 on the outer periphery of the wall 11 of the tube 10 and extending along the outer periphery 11a of the wall 11. Specifically, the magnet wire 33 is wound around the connecting portions 21b of the outer columns 21. For example, the outer coil structure 6 is formed by winding one magnet wire 33 across the multiple outer columns 21 of the tube 10. Specifically, for example, the magnet wire 33 is wound around the outer columns 21 alternately from one side in the axial x direction and the other side in the axial x direction for every two adjacent outer columns 21 toward one side in the circumferential direction, turned back after going around the cylinder 10 once, and then wound around the outer columns 21 again in the same manner toward the other side in the circumferential direction, thereby forming the outer coil structure 6. In this case, each outer coil 30 is formed around the two outer columns 21, straddling them. Therefore, the outer coil 30 extends into a space G1 that is open to the outside in the radial direction between the two outer columns 21.

[0024] In this way, at the portion where two circumferentially adjacent outer coils 30 are connected, two portions of the magnet wire 33 intersect to form an intersection 34 (see FIGS. 5 to 11 ). Furthermore, the outer coil structure 6 of this example is not an endless loop, but an ended loop, and as shown in FIGS. 7 and 12 , ends 6 a, 6 b of the outer coil structure 6 are formed in the outer coil 30 formed by starting to wind the magnet wire 33 around multiple outer columns 21 and in the outer coil 30 formed by folding back the magnet wire 33. The multiple outer coils 30 are not connected at the ends 6 a, 6 b of the outer coil structure 6. As shown in FIG. 12 , both ends 33 a, 33 b of the magnet wire 33 are drawn out from the outer coil 30 formed by starting to wind the magnet wire 33.

[0025] 5 to 8, in each outer coil 30, the one end 31 is the portion on one end side in the circumferential direction, and the other end 32 is the portion on the other end side in the circumferential direction. In the outer coils 30, excluding the outer coils 30 formed by starting to wind the magnet wire 33 and the outer coils 30 formed by folding back the magnet wire 33, the one end 31 and the other end 32 are portions of an intersection 34 where two portions of the magnet wire 33 connected to an adjacent outer coil 30 intersect. In the outer coils 30 formed by starting to wind the magnet wire 33, as shown in FIGS. 7 and 8, the one end 31 is a portion where the magnet wire 33 that closes this outer coil 30 continues, and the other end 32 is a portion of an intersection 34 where two portions of the magnet wire 33 connected to an adjacent outer coil 30 intersect. Furthermore, in the outer coil 30 formed by folding back the magnet wire 33, as shown in Figures 7 and 8, one end 31 is the intersection 34 where two parts of the magnet wire 33 connecting to the adjacent outer coil 30 intersect, and the other end 32 is the continuous part of the magnet wire 33 that closes this outer coil 30.

[0026] In this example, as described above, sixteen outer columns 21, numbered from the first to sixteenth, are provided, and as shown in FIGS. 8 and 12 , eight pairs of two outer columns 21, each wound with one outer coil 30, are arranged circumferentially. Furthermore, eight outer coils 30, numbered from the first to eighth, are formed using magnet wire 33. Each of the first to eighth outer coils 30 is wound across two outer columns 21 of a corresponding pair among the first to sixteenth outer columns 21. The two magnet wires 33 connecting the first outer coil 30 and the second outer coil 30 intersect, and similarly, at the connection between two adjacent outer coils 30 among the second to eighth outer coils 30, two portions of the magnet wire 33 intersect. Furthermore, the first outer coil 30 and the eighth outer coil 30 are not connected to each other, and the first and eighth outer coils 30 form the ends 6a and 6b of the outer coil structure 6. The first outer coil 30 is an outer coil formed by starting to wind the magnet wire 33 around the multiple outer columns 21. The eighth outer coil 30 is an outer coil 30 formed by folding back the magnet wire 33.

[0027] Note that each outer coil 30 is not limited to being formed around two outer columns 21, and may be formed around other numbers of outer columns 21. Also, while the case where the magnet wire 33 is wound around once has been described, the winding form of the magnet wire 33 is not limited to this, and the magnet wire 33 may be wound around two or more times. In other words, the outer coil structure 6 formed by winding the magnet wire 33 may have, for example, one layer in the radial direction, or multiple layers such as two, three, four, or five layers. If the number of turns or layers is large, the output signal or the signal to be detected (for example, the amplitude of the signal waveform) can be amplified. Furthermore, the end (one end 31) of the first outer coil 30 on the side of the eighth outer coil 30 and the end (the other end 32) of the eighth outer coil 30 on the side of the first outer coil 30 do not have an intersection 34 where two parts of the magnet wire 33 intersect, but the magnet wire 33 may be wound so that the shape of the corresponding part of the intersection 34 is formed at one end 31 of the first outer coil 30 and the other end 32 of the eighth outer coil 30, respectively.

[0028] The multiple inner coils 40, like the multiple outer coils 30, are connected in a circumferential direction around the axis x. As schematically shown in FIGS. 5 to 11 , the multiple inner coils 40 form a cylindrical shape (hereinafter referred to as the "inner coil structure") 7 extending annularly along the inner circumferential surface 11b of the wall 11 of the tube 10. The inner coil structure 7 is a structure formed by arranging multiple inner coils 40. The inner coil structure 7 has the same configuration as the outer coil structure 6, and in the inner coil structure 7, the same number of inner coils 40 as the outer coils 30 constituting the outer coil structure 6 are arranged annularly so as to be aligned along an annular surface around the axis x. The multiple inner coils 40 are arranged annularly, for example, so as to be aligned along a cylindrical surface with the axis x as the central axis. Furthermore, each inner coil 40 has a shape that surrounds a space. Furthermore, each inner coil 40 has a shape such that the space surrounded by each inner coil 40 follows an annular surface around the axis x, for example. The number of outer coils 30 and inner coils 40 in the outer coil structure 6 and inner coil structure 7 respectively corresponds to the axial multiplication factor set in the angle sensor 1 .

[0029] The inner coil 40 is, for example, a coil formed by winding magnet wire 43, which is an example of a conductive conductor 43. As described above, the multiple inner coils 40 are formed by winding magnet wire 34 around multiple inner posts 22. The multiple inner coils 40 have an annular shape wound radially around the tube 10 and surround a planar space facing the radial direction. As shown in FIGS. 5 and 6 , the multiple inner coils 40 are formed in series around the axis x on the inner circumferential surface 11b of the wall 11 of the tube 10, thereby forming the inner coil structure 7 shown in FIGS. 10 and 11 . In this way, the multiple outer coils 30 and the multiple inner coils 40 face each other in the radial direction via the wall 11, and the wall 11 separates the multiple outer coils 30 and the multiple inner coils 40 in the radial direction. Note that the conductive conductor 43 forming the inner coil 40 is not limited to magnet wire.

[0030] 5, 6, 8, and 12, a magnet wire 43 is wound around each of the multiple inner columns 22 in the radial direction, serving as a conductor 43, and multiple annular inner coils 40 are formed around the multiple inner columns 22 in the radial direction, forming an inner coil structure 7 on the inner periphery of the wall 11 of the tube 10 and extending along the inner circumferential surface 11b of the wall 11. Specifically, the magnet wire 43 is wound around the connecting portion 22b of the inner columns 22. For example, the inner coil structure 7 is formed by winding one magnet wire 43 across the multiple inner columns 22 of the tube 10. Specifically, for example, the magnet wire 43 is wound around the inner columns 22 alternately from one side in the axial x direction and the other side in the axial x direction for every two adjacent inner columns 22 toward one side in the circumferential direction, turned back after going around the cylinder 10 once, and then wound around the inner columns 22 again in the same manner toward the other side in the circumferential direction, thereby forming the inner coil structure 7. In this case, each inner coil 40 is formed around the two inner columns 22, straddling the two inner columns 22. Therefore, the inner coil 40 extends into a space G2 that is open radially inward between the two inner columns 22.

[0031] In this way, at the portion where two circumferentially adjacent inner coils 40 are connected, two portions of the magnet wire 43 intersect to form an intersection 44 (see FIGS. 5 to 11 ). Furthermore, the inner coil structure 7 of this example is not an endless loop, but an ended loop, and ends 7a and 7b of the inner coil structure 7 are formed in the inner coil 40 formed by starting to wind the magnet wire 43 around multiple inner columns 22 and in the inner coil 40 formed by folding back the magnet wire 43. The multiple inner coils 40 are not connected at the ends 7a and 7b of the inner coil structure 7. As shown in FIG. 12 , both ends 43a and 43b of the magnet wire 43 are drawn out from the inner coil 40 formed by starting to wind the magnet wire 43.

[0032] 5, 6, 8, and 9, in each inner coil 40, the one end 41 is the portion on one end side in the circumferential direction, and the other end 42 is the portion on the other end side in the circumferential direction. In the inner coils 40 excluding the inner coils 40 formed by starting to wind the magnet wire 43 and the inner coils 40 formed by folding back the magnet wire 43, the one end 41 and the other end 42 are portions of an intersection 44 where two portions of the magnet wire 43 connected to the adjacent inner coil 40 intersect. In the inner coils 40 formed by starting to wind the magnet wire 43, as shown in FIGS. 8 and 9, the one end 41 is a portion where the magnet wire 43 that closes this inner coil 40 continues, and the other end 42 is a portion of an intersection 44 where two portions of the magnet wire 43 connected to the adjacent inner coil 40 intersect. Furthermore, in the inner coil 40 formed by folding back the magnet wire 43, as shown in Figures 8 and 9, one end 41 is the intersection 44 where two parts of the magnet wire 43 connecting to the adjacent inner coil 40 intersect, and the other end 42 is the continuous part of the magnet wire 43 that closes this inner coil 40.

[0033] In this example, as described above, sixteen inner columns 22, numbered 1 to 16, are provided, and as shown in Figures 8 and 12, eight pairs of two inner columns 22, each wound with one inner coil 40, are arranged circumferentially. The first to sixteenth inner columns 22 correspond to the first to sixteenth outer columns 21, respectively, and corresponding outer columns 21 and inner columns 22 form the same column 10. Furthermore, eight inner coils 40, numbered 1 to 8, are formed using magnet wire 43. The first to eighth inner coils 40 are each wound across the two inner columns 22 of the corresponding pair among the first to sixteenth inner columns 22. Two portions of the magnet wire 43 connecting the first inner coil 40 and the second inner coil 40 intersect, and similarly, two portions of the magnet wire 43 intersect at the portion where two adjacent inner coils 40 between the second to eighth inner coils 40 are connected. Furthermore, the first inner coil 40 and the eighth inner coil 40 are not connected, and the first and eighth inner coils 40 form the ends 7a and 7b of the inner coil structure 7. The first inner coil 40 is an inner coil formed by starting to wind the magnet wire 43 around multiple inner columns 22. Furthermore, the eighth inner coil 40 is an inner coil 40 formed by folding back the magnet wire 43.

[0034] As described above, the outer coil structure 6 and the inner coil structure 7 have the same configuration, but are arranged circumferentially offset from each other on the tube 10. Therefore, the intersections 34 of the outer coil structure 6 and the inner coils 40 of the inner coil structure 7 are positioned to overlap each other in the radial direction. Specifically, the radial projection of each intersection 34 of the outer coil structure 6 overlaps one or two inner coils 40 of the inner coil structure 7. Similarly, the intersections 44 of the inner coil structure 7 and the outer coils 30 of the outer coil structure 6 are positioned to overlap each other in the radial direction. Specifically, the radial projection of each intersection 44 of the inner coil structure 7 overlaps one or two outer coils 30 of the outer coil structure 7. In addition, a part of the space surrounded by the outer coil 30 and a part of the space surrounded by the inner coil 30 are offset in the circumferential direction, and another part of the space surrounded by the outer coil 30 and another part of the space surrounded by the inner coil 40 overlap in the circumferential direction and face each other radially via the wall 11.

[0035] Specifically, for example, the outer coil structure 6 and the inner coil structure 7 are offset in the circumferential direction by one pillar 20. That is, as shown in Figures 10 to 12, the first outer coil 30 of the outer coil structure 6 is formed around the first outer pillar 21 and the second outer pillar 21, while the first inner coil 40 of the inner coil structure 7 is formed around the second inner pillar 22 and the third inner pillar 22. Therefore, the space surrounded by the outer coil 30 is offset in the circumferential direction from the space surrounded by the inner coil 40 by half the width of the space surrounded by the outer coil 30.

[0036] Note that each inner coil 40 is not limited to being formed around two inner posts 22, but may be formed around other numbers of inner posts 22. However, the inner coil structure 7 has the same configuration as the outer coil structure 6, and the number of inner posts 22 across which each inner coil 40 straddles is equal to the number of outer posts 21 across which each outer coil 30 straddles. Furthermore, while the magnet wire 33 has been described as being wound around one circumference, the winding pattern of the magnet wire 33 is not limited to this and may be wound around two or more circumferences. In other words, the coil formed by winding the magnet wire 33 may have, for example, one layer, two, three, four, five, or more layers in the radial direction. A large number of turns or layers can amplify the output signal or the signal to be detected (e.g., the amplitude of the signal waveform). Furthermore, although an intersection 45 where two portions of the magnet wire 33 intersect is not formed at the end of the first inner coil 40 facing the eighth inner coil 40 and the end of the eighth inner coil 40 facing the first inner coil 40, the magnet wire 33 may be wound so that the shape of the corresponding portion of the intersection 44 is formed at the end of the first inner coil 40 facing the eighth inner coil 40 and the end of the eighth inner coil 40 facing the first inner coil 40, respectively.

[0037] As shown in FIGS. 5 to 7 and 9, the excitation circuit 8 is housed in the groove 12e of the base end portion 12 of the cylinder 10.

[0038] Fig. 13 is a perspective view schematically showing the configuration of the frame 60, and Fig. 14 is a rear view schematically showing the configuration of the frame 60. As described above, in the stator 3, the cylinder 10 is supported by and fixed to the frame 60. Note that the cylinder 10 may be fixed to the frame 60 in a removably manner.

[0039] As shown in FIGS. 13 and 14 , the frame 60 has a cover 61 that covers the multiple outer coils 30 attached to the tube 10. The cover 61 is, for example, a cylindrical portion corresponding to the tube 10. The cover 61 is formed, for example, so that the tube 10 is fixed thereto. The cover 61 forms, for example, a space capable of accommodating the tube 10 of the stator 3 therein and has an inner circumferential surface 62 that defines this space. The cover 61 also has an outer circumferential surface 63 that faces away from the inner circumferential surface 62 on the outer peripheral side. The inner circumferential surface 62 is a cylindrical surface extending along the axis x, and the inner circumferential surface 62 extends, for example, on a cylindrical surface with the axis x as its central axis. Specifically, the inner circumferential surface 62 of the cover 61 is formed so that the outer post 21 of the tube 10 can be accommodated therein. When the tube 10 is accommodated in the space formed by the inner circumferential surface 62, the inner circumferential surface 62 faces radially opposite the outer circumferential surface 21 a of the outer post 21. The inner circumferential surface 62 of the cover 61 has an inner diameter such that, when the tube 10 is housed in the space formed by the inner circumferential surface 62, it comes into contact with the outer circumferential surface 21 a of the outer post 21 and the tube 10 is press-fitted into the space formed by the inner circumferential surface 62. In this manner, the tube 10 is press-fitted and fixed into the cover 61, and is fixed to the frame 60. Note that the inner circumferential surface 62 of the cover 61 may have a size (inner diameter) such that, when the tube 10 is housed in the space formed by the inner circumferential surface 62, it does not come into contact with the outer circumferential surface 21 a of the outer post 21, and an annular gap is formed between the inner circumferential surface 62 and the outer circumferential surface 21 a of the outer post 21. In this case, the tube 10 is fixed to the frame 60 by, for example, bonding using an adhesive. Furthermore, when the tube 10 is housed in the space formed by the inner circumferential surface 62, the outer circumferential surface 12 e of the base end 12 of the tube 10 may come into contact with the inner circumferential surface 62 of the cover 61.

[0040] 13 and 14 , a flange portion 64, which is an annular portion that protrudes inward from an inner peripheral surface 62, is formed on the cover 61 of the frame 60. The flange portion 64 is formed, for example, on one end of the inner peripheral surface 62 in the direction of the axis x. When the tube 10 is accommodated in the space formed by the inner peripheral surface 62 of the cover 61, the flange portion 64 engages (contacts) with the tube 10 in the direction of the axis x, and serves as a stopper for the tube 10.

[0041] When the tube 10 is accommodated in the space formed by the inner circumferential surface 62 of the cover 61, the inner circumferential surface 62 of the cover 61 is configured to cover the entire tube 10. In other words, the width of the inner circumferential surface 62 of the cover 61 in the axial x direction is the same as or larger than the width of the tube 10 in the axial x direction. Note that when the tube 10 is accommodated in the space formed by the inner circumferential surface 62 of the cover 61, the inner circumferential surface 62 of the cover 61 does not have to cover the entire tube 10. In other words, the width of the inner circumferential surface 62 of the cover 61 in the axial x direction may be smaller than the width of the tube 10 in the axial x direction. For example, when the tube 10 is accommodated in the space formed by the inner circumferential surface 62 of the cover 61, the width of the inner circumferential surface 62 of the cover 61 in the axial x direction may be such that it covers the wall 11 of the tube 10.

[0042] 13 and 14 , the frame 60 has an attachment portion 65, which is a portion that is attached to an external device as an application target. As shown in FIGS. 13 and 14 , the attachment portion 65 is provided, for example, on the outer peripheral surface 63 of the cover 61 and protrudes outward from the cover 61. The attachment portion 65 also has a hole portion (hereinafter referred to as a through hole) 65a through which a fixing member such as a bolt is passed, so that the attachment portion 65 can be attached to an external device via the fixing member. The frame 60 has, for example, three attachment portions 65. Note that the number of attachment portions 65 included in the frame 60 is not limited thereto. As shown in FIGS. 13 and 14 , the cover 61 also has, for example, a retaining portion 66. As shown in FIGS. 13 and 14 , the retaining portion 66 extends from the outer peripheral surface 63 of the cover 61 along the axis x toward the other side of the axis x. 1 to 3, the holding unit 66 is a portion that holds the substrate 9. For example, one or more electronic components and one or more wirings are provided on the substrate 9. These multiple electronic components may constitute a control unit that performs calculations or processing.

[0043] The frame 60 is, for example, integrally molded from the same material, and each component of the frame 60 is connected together. That is, the cover 61, flange 64, mounting portion 65, and holding portion 66 are each parts of the frame 60 integrally formed from the same material and connected together. The frame 60 is an insulating member, for example, a resin member. The frame 60 is made of, for example, a resin material, a non-magnetic material, or a non-conductive material. Note that the non-magnetic material may be non-conductive. The material of the frame 60 may be the same as the material of the tube 10. Note that any or all of the components of the frame 60 may be formed as separate bodies. In this case, the frame 60 is formed by assembling the components formed as separate bodies by adhesive or the like.

[0044] FIG. 15 is a cross-sectional view showing the stator 3 in an assembled state in which the tube 10 is fixed to the frame 60 and the tube 10 and the frame 60 are assembled. FIG. 15 shows a cross section taken along a plane including the axis x of the tube 10 and the frame 60 in the assembled state. As shown in FIG. 15 , in the assembled stator 3, the tube 10 is accommodated in a space formed by the inner circumferential surface 62 of the cover 61 of the frame 60, and the tube 10 is fixed to the frame 60. As described above, the tube 10 is fixed to the frame 60 by, for example, engagement, fitting, or bonding. The tube 10 may also be fixed to the frame 60 by, for example, adhesive bonding. Note that the fixing configuration of the tube 10 to the frame 60 is not limited to these configurations. As shown in FIG. 15 , in the assembled state, the tube 10 is entirely covered by the cover 61 in the axial x direction. Note that, as described above, in the assembled state, the tube 10 does not have to be entirely covered by the cover 61 in the axial x direction. 15, in the assembled state, the end surface 11c of the wall 11 of the cylinder 10 is in contact with the flange portion 64 of the cover 61. Note that in the assembled state, the end surface 11c of the cylinder 10 does not have to be in contact with the flange portion 64 of the cover 61. Note that the end surface 11c of the wall 11 is the end surface of the wall 11 in the direction of the axis x.

[0045] In this manner, in the assembled stator 3, the outer peripheral surface 11a of the wall 11 of the tube 10 is covered by the cover 61 of the frame 60. Therefore, in the assembled state, the outer coil structure 6 attached to the wall 11 of the tube 10 of the stator 3 is covered by the cover 61 of the frame 60. This makes it possible to protect the outer coil structure 6 without protecting it with potting or the like, and to prevent objects and the like from coming into contact with the outer coil structure 6 from the outside. Furthermore, when the groove 12e of the base end portion 12 of the tube 10 is covered by the cover 61, the excitation circuit 8 in the groove 12e can also be protected from external contact without protecting it with potting or the like.

[0046] 1 to 4 , in the angle sensor 1, the rotor 2 is housed in a space surrounded by the inner circumferential surfaces 22a of the multiple inner posts 22 of the cylinder 10 of the stator 3. The outer circumferential surface 52 of the rotor 2 faces radially the multiple inner posts 22 of the cylinder 10 of the stator 3, with an annular space between them, and also faces radially the multiple outer posts 21 via the multiple inner posts 22 and the wall 11. The multiple metal bodies 5 of the rotor 2 face radially the multiple inner coils 40 wound around the multiple inner posts 22 and the multiple outer coils 30 wound around the multiple outer posts 21. In this way, the rotor 2 and the stator 3 form an inductive angle sensor, and the multiple outer coils 30 and the multiple inner coils 40 form detection coils. A magnetic space or magnetic gap is formed between the rotor 2 and the stator 3.

[0047] In the angle sensor 1, a radially directed magnetic flux whose magnitude periodically changes acts on the multiple outer coils 30 and the multiple inner coils 40. Specifically, as described above, the cylinder 10 of the stator 3 is provided with the excitation circuit 8 (see FIGS. 9 and 15 ). The excitation circuit 8 is a magnetic circuit that generates a periodically changing magnetic flux that acts on each of the multiple outer coils 30 and the multiple inner coils 40. Meanwhile, as described above, the multiple metal bodies 5 are arranged in the circumferential direction around the axis x and cross the magnetic flux generated by the excitation circuit 8 as the rotor 2 rotates. Furthermore, the projection of the metal body 5, which has a portion extending along the axis x, onto the outer coils 30 and the inner coils 40 in the radial direction moves as the rotor 2 rotates. Therefore, the magnetic flux from the excitation circuit 8 that acts on each of the multiple outer coils 30 and the multiple inner coils 40 is affected by eddy currents generated in the metal body 5 and cancels out, thereby periodically changing as the rotor 2 rotates. As a result, an electromotive force that changes with the rotation of the rotor 2 is generated in the outer coils 30 and the inner coils 40 due to electromagnetic induction, and signals that change with the rotation of the rotor 2 are detected from the outer coils 30 and the inner coils 40. Based on the detection signals from the outer coils 30 and the inner coils 40, the rotation angle of the rotor 2 is detected in an external electric circuit device.

[0048] The angle sensor 1 according to this embodiment has the above-described configuration, in which multiple outer coils 30 are formed on multiple outer columns 21, multiple inner coils 40 are formed on multiple inner columns 22, and the wall 11 of the tube 10 is interposed between the multiple outer coils 30 and the multiple inner coils 40. In this manner, in the angle sensor 1, the multiple outer coils 30 and the multiple inner coils 40 are radially spaced apart and do not overlap each other. This allows the outer coils 30 and the inner coils 40 to be shaped to fit the multiple outer columns 21 and the multiple inner columns 22, preventing the shapes of the outer coils 30 and the inner coils 40 from differing from the desired shapes. This prevents variations in the detection signals output from the multiple outer coils 30 and the multiple inner coils 40. This improves the detection accuracy of the angle sensor 1.

[0049] 2 to 4, the rotor 2 is located on the inner circumferential side of the tube 10 of the stator 3, and the multiple outer coils 30 are located radially farther from the multiple metal bodies 5 of the rotor 2 than the multiple inner coils 40. Therefore, the influence of eddy currents from the metal bodies 5 is greater on the inner coil 40 than on the outer coil 30. In contrast, as shown in FIG. 8, the circumferential extension angle α of the outer column 21 and the circumferential extension angle α of the inner column 22 are equal or approximately equal, and the width of the outer column 21 in the axial x direction and the width of the inner column 22 in the axial x direction are equal or approximately equal. Therefore, the area S1 (see FIG. 12) of the space surrounded by the outer coil 30 is larger than the area S2 (see FIG. 12) of the space surrounded by the inner coil 40. Therefore, the multiple outer coils 30 are affected by eddy currents from the metal body 5 over a larger range than the multiple inner coils 40. This makes it possible to suppress the influence of eddy currents from the metal body 5 from differing between the outer coils 30 and the inner coils 40. This makes it possible to suppress variations in the detection signals output from the outer coils 30 and the inner coils 40. This also makes it possible to improve the detection accuracy of the angle sensor 1.

[0050] Note that the outer column 21, the inner column 22, and the sizes and shapes of the outer column 21 and the inner column 22 may be adjusted to adjust the area S1 surrounded by the outer coils 30 and the area S2 surrounded by the inner coils 40 so as to prevent the influence of eddy currents from the metal body 5 from differing between the outer coils 30 and the inner coils 40. For example, by setting the extension angle α of the outer column 21 and the extension angle α of the inner column 22 to different angles, the area S1 surrounded by the outer coil 30 can be adjusted relative to the area S2 surrounded by the inner coil 40.

[0051] In this way, the angle sensor 1 according to the embodiment of the present invention can improve detection accuracy.

[0052] Next, modified examples of the angle sensor 1 will be described. Fig. 16 is a partial cross-sectional view showing a cross section of an angle sensor 1A according to a modified example taken along a plane including the axis x. As described above, the angle sensor 1 is a so-called inner rotor type angle sensor, whereas the angle sensor 1A according to the modified example is a so-called outer rotor type angle sensor. Hereinafter, for the angle sensor 1A, components that are the same as or have similar functions to those of the above-described angle sensor 1 will be assigned the same reference numerals and their description will be omitted, and only different components will be described.

[0053] As shown in FIG. 16 , the angle sensor 1A includes a stator 3A that is different from the stator 3 described above. Specifically, the stator 3A has a frame 67 that is different from the frame 60 of the stator 3. The frame 67 has a cover 68 that is different from the cover 61 of the frame 60. The cover 68 is, for example, a cylindrical portion that corresponds to the cylinder 10. The cover 68 is formed so as to be able to support the cylinder 10 of the stator 3 on its outer periphery and has a cylindrical outer periphery surface 68a facing the outer periphery. The outer periphery surface 68a is, for example, a surface that extends on a cylindrical surface or a substantially cylindrical surface with the axis x as its central axis. Specifically, the outer periphery surface 68a of the cover 68 is formed so as to be able to be housed inside the multiple inner posts 22 of the cylinder 10. When the cover 68 is housed inside the cylinder 10, the outer periphery surface 68a faces radially opposite the inner periphery surfaces 22a of the multiple inner posts 22. The outer peripheral surface 68a of the cover 68 has an outer diameter such that, when the cover 68 is housed inside the tube 10, it comes into contact with the inner peripheral surfaces 22a of the multiple inner posts 22, allowing the cover 68 to be press-fitted into the tube 10. In this manner, the tube 10 is press-fitted and fixed to the cover 68, and is then fixed to the frame 67. Note that, for example, the outer peripheral surface 68a of the cover 68 may have a size (outer diameter) such that, when the cover 68 is housed inside the tube 10, it does not come into contact with the inner peripheral surfaces 22a of the multiple inner posts 22, and an annular gap is formed between the outer peripheral surface 68a and the inner peripheral surfaces 22a of the multiple inner posts 22. In this case, the tube 10 is fixed to the frame 67 by, for example, bonding using an adhesive.

[0054] 16, similar to the frame 60, the frame 67 is provided with a flange 64, an attachment portion 65, and a holding portion 66. The flange 64 is provided at the end of the axis x of the cover 68, and extends outward from the outer peripheral surface 68a of the cover 68. Similar to the flange 64 of the frame 60 described above, the flange 64 is adapted to come into contact with the end surface 11c of the tube 10 fixed to the cover 68.

[0055] In the angle sensor 1A, the outer peripheral surfaces 21a of the multiple outer posts 21 face the inner peripheral surface 51 of the cylinder 50 of the rotor 2 with an annular gap therebetween. Furthermore, the multiple metal bodies 5 in the rotor 2 form conductor structures 4, for example, on or near the inner peripheral surface 51. In this way, in the angle sensor 1A, the multiple outer coils 30 and the multiple inner coils 40 face the multiple metal bodies 5 of the rotor 2 from the inner peripheral side. The angle sensor 1A also functions in the same way as the angle sensor 1 described above and achieves the same effects.

[0056] In the angle sensor 1A, the rotor 2 is located on the outer periphery of the tube 10 of the stator 3, and the multiple inner coils 40 are located radially farther from the metal body 5 of the rotor 2 than the multiple outer coils 30. Therefore, for example, the area S2 surrounded by the multiple inner coils 40 is larger than the area S1 surrounded by the multiple outer coils 30. For example, the extension angle α of the multiple outer posts 21 (see FIG. 8 ) and the extension angle α of the multiple inner posts 22 (see FIG. 8 ) are adjusted to adjust the area S2 surrounded by the inner coil 40 relative to the area S1 surrounded by the outer coil 30. For example, the area S2 surrounded by the inner coil 40 is adjusted so as to be larger than the area S1 surrounded by the outer coil 30.

[0057] Next, a modified example of the tube 10 of the stator 3 will be described. FIG. 17 is a perspective view of a tube 10A according to the modified example, FIG. 18 is a cross-sectional view of the tube 10A according to the modified example taken along a plane including the axis x, and FIG. 19 is a partially enlarged cross-sectional view of FIG. 18. Note that FIGS. 17 to 19 show the outer coil 30 and the inner coil 40. In FIG. 18, the upper side of the axis x indicates a cross-section passing through a post 20A (described later), and the lower side of the axis x indicates a cross-section passing through a space G3 (described later). FIG. 19 also shows the cross-section of the lower side of FIG. 18. The tube 10A according to this modified example is used in the outer rotor angle sensor 1A described above. Hereinafter, for the tube 10A, components that are the same as or have similar functions to those of the tube 10 described above will be assigned the same reference numerals and their description will be omitted, and only different components will be described.

[0058] As shown in Figures 18 and 19, the tube 10A has a wall 11A different from the wall 11 of the tube 10 described above and multiple pillars 20A different from the multiple pillars 20 of the tube 10 described above. The tube 10A has multiple walls 11A, which, like the wall 11 of the tube 10 described above, radially separate the multiple outer coils 30 and the multiple inner coils 40. Specifically, the tube 10A has multiple walls 11A corresponding to the multiple pillars 20A. Unlike the wall 11 of the tube 10, the multiple walls 11A are not connected to the base end 12. Furthermore, the multiple walls 11A are spaced apart in the circumferential direction and extend around the axis, similar to the wall 11 of the tube 10. Therefore, the tube 10A has a space G3 between two pillars 20A adjacent to each other in the circumferential direction, where the space G1 and the space G2 of the tube 10A are radially connected. The multiple walls 11A are arranged at equal or approximately equal angular intervals in the circumferential direction along a cylindrical surface having the axis x as its central axis. As shown in Figures 17 to 19, each of the multiple columns 20A has an outer column 21 and an inner column 22A. The inner column 22A is formed by the connecting portion 22b of the inner column 22 of the above-mentioned tube 10, and unlike the above-mentioned inner column 22, it does not have an end portion 22c. In each column 20A, the outer column 21 is provided on the wall 11A, similar to the outer column 21 of the above-mentioned tube 10, and the inner column 22A is provided on the wall 11A, similar to the inner column 22 of the above-mentioned tube 10.

[0059] Specifically, as shown in Figures 18 and 19, each of the multiple walls 11A has an outer peripheral surface 11Aa that faces the outer peripheral side, an inner peripheral surface 11Ab that faces the inner peripheral side, an end surface 11Ad that faces the end surface 12a of the base end portion 12 in the axial x direction, and an end surface 11Ac that faces the end surface 11Ad in the axial x direction. The end surface 11Ad faces the end surface 12a of the base end portion 12 across a gap in the axial x direction. The outer peripheral surface 11Aa extends, for example, along a cylindrical surface extending along the axial x, and specifically, for example, extends on a cylindrical surface or a substantially cylindrical surface with the axial x as its central axis. The inner peripheral surface 11Ab extends parallel or substantially parallel to the outer peripheral surface 11Aa.

[0060] 18 and 19, an outer post 21 is formed on the outer peripheral surface 11Aa of the wall 11A. The outer peripheral surface 11Aa of the wall 11A and an end 21c of the outer post 21 face each other via a connecting portion 21b, and an annular groove is formed around the connecting portion 21b, similar to the tube 10. An inner post 22A is formed on the inner peripheral surface 11Ab of the wall 11A.

[0061] 17 to 19, the tube 10A has a wall 13, which is a cylindrical portion extending along the axis x, on the inner periphery of the multiple inner columns 22A. The wall 13 has an outer periphery 13a that faces the outer periphery and an inner periphery 13b that faces the inner periphery. The outer periphery 13a and the inner periphery 13b are back-to-back facing each other. The wall 13 has a shape that follows a cylindrical surface whose central axis is the axis x. The outer periphery 13a extends on a cylindrical surface or a nearly cylindrical surface whose central axis is the axis x, and the inner periphery 13b is a cylindrical surface or a nearly cylindrical surface whose central axis is the axis x.

[0062] 18 and 19, the inner peripheral ends of the inner columns 22A of the multiple columns 20A are each connected to the outer peripheral surface 13a of the wall 13. In this way, in the tube 10A, the multiple walls 11A face the outer peripheral surface 13a of the wall 13 via the inner columns 22A, and each of the multiple inner columns 22A is sandwiched between the inner peripheral surfaces 11Ab of the multiple walls 11A and the outer peripheral surface 13a of the wall 13. Similar to the tube 10, an annular groove is formed around each inner column 22A by the inner peripheral surface 11Ab of the wall 11A and the outer peripheral surface 13a of the wall 13. Furthermore, as shown in FIGS. 17 to 19, the base end 12 is provided at the end of the wall 13 in the axial x direction, adjacent to the column 20A in the axial x direction, and protrudes outward from the outer peripheral surface 13a of the wall 13.

[0063] As shown in Figures 17 to 19, similar to the case of the above-mentioned tube 10, the tube 10A also has multiple outer coils 30 formed around multiple outer columns 21, and multiple inner coils 40 formed around multiple inner columns 22A.

[0064] The cylinder 10A is attached to a frame 67 shown in FIG. 16 in the same manner as the cylinder 10, thereby constituting a stator 3A. Specifically, a cover 68 of the frame 67 is housed inside the inner circumferential surface 13b of the wall 13 of the cylinder 10A, and the cylinder 10A is fixed to the frame 67. For example, the outer circumferential surface 68a of the cover 68 has an outer diameter such that, when the cover 68 is housed inside the inner circumferential surface 13b of the wall 13 of the cylinder 10A, it comes into contact with the inner circumferential surface 13b of the wall 13, and the cover 68 is press-fitted into the interior of the cylinder 10A. In this way, the cylinder 10A is press-fitted and fixed to the cover 68, and is then fixed to the frame 67. The outer peripheral surface 68a of the cover 68 may have a size (outer diameter) such that, when the cover 68 is housed inside the inner peripheral surface 13b of the wall 13 of the tube 10A, the outer peripheral surface 68a does not contact the inner peripheral surface 13b of the wall 13, and an annular gap is formed between the outer peripheral surface 68a and the inner peripheral surface 13b of the wall 13. In this case, the tube 10A is fixed to the frame 67 by, for example, bonding using an adhesive. Furthermore, in an assembled state of the stator 3A in which the tube 10A is attached to the frame 67, the end surface 13c of the wall 13 of the tube 10A contacts the flange portion 64 of the cover 68. In the assembled state, the end surface 13c of the wall 13 of the tube 10A does not have to contact the flange portion 64 of the cover 68. The end surface 13c of the wall 13 is the end surface of the wall 13 in the direction of the axis x.

[0065] In the angle sensor 1A having the cylinder 10A, similarly to the angle sensor 1A described above (see FIG. 16 ), the outer peripheral surfaces 21 a of the multiple outer posts 21 face the inner peripheral surface 51 of the cylinder 50 of the rotor 2 with an annular gap therebetween, and the multiple outer coils 30 and the multiple inner coils 40 face the multiple metal bodies 5 of the rotor 2 from the inner peripheral side. The angle sensor 1A having the cylinder 10A also functions in the same manner as the angle sensors 1 and 1A described above, and achieves the same effects.

[0066] Although the present invention has been described above through the above embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0067] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the scope of the present invention. Furthermore, the above-described embodiments do not limit the scope of the present invention, and the present invention may include any and all applications. The components of the above-described embodiments, as well as their arrangement, materials, conditions, shape, size, etc., are not limited to those illustrated and may be modified as appropriate. For example, the present invention includes differences that arise during implementation due to manufacturing tolerances, etc. Furthermore, components illustrated in different embodiments may be partially substituted or combined within the scope of technical inconsistency. Furthermore, the various configurations may be selectively combined as appropriate to achieve at least some of the above-described problems and effects.

[0068] 1, 1A Angle sensor, 2 Rotor (rotating body), 3, 3A Stator, 4 Conductor structure, 5 Metal body (conductor), 6 Outer coil structure, 6a, 6b End, 7 Inner coil structure, 8 Excitation circuit, 9 Substrate, 10, 10A Cylinder, 11, 11A Wall, 11a, 11Aa Outer peripheral surface, 11b, 11Ab Inner peripheral surface, 11c, 11Ac, 11Ad End surface, 12 Base end, 12a End surface, 12b End surface, 12c Outer peripheral surface, 12d Inner peripheral surface, 12e Groove, 13 Wall, 13a Outer peripheral surface, 13b Inner peripheral surface, 13c End surface, 20 Column, 21 Outer column, 21a Outer peripheral surface, 21b Connecting portion, 21c End, 21d, 21e Side end, 22, 22A Inner column, 22a: inner peripheral surface, 22b, 22Ab: connecting portion, 22c: end portion, 22d, 22e: side end portion, 30: outer coil, 31: one end portion, 32: other end portion, 33: conducting wire (magnet wire), 33a, 33b: end portion, 34: intersection portion, 40: inner coil, 41: one end portion, 42: other end portion, 43: conducting wire (magnet wire), 43a, 43b: end portion, 44: intersection portion, 50: cylinder, 51: inner peripheral surface, 52: outer peripheral surface, 53, 54: end surface, 60, 67: frame, 61, 68: cover, 62: inner peripheral surface, 63, 68a: outer peripheral surface, 64: flange, 65: mounting portion, 65a: through hole, 66: holding portion, G1, G2, G3: space, r1, r2: radial line, S1, S2: area, x Axis, α extension angle

Claims

1. A cylinder having a plurality of columns extending in the radial direction, a plurality of outer coils and a plurality of inner coils wound around the plurality of columns, wherein in the circumferential direction, the outer coil has one end and the other end, and in the circumferential direction, the inner coil has one end and the other end, and the plurality of outer coils and the plurality of inner coils are radially separated, an angle sensor.

2. The outer coil is wound across adjacent first and second columns among the plurality of columns. The angle sensor according to claim 1.

3. The inner coil is wound across the adjacent second and third columns among the plurality of columns. The angle sensor according to claim 1.

4. Taking the outer coil as the outer first coil, the plurality of outer coils include an outer second coil which is the outer coil adjacent to the outer first coil in the circumferential direction, and two conductors connecting the outer first coil and the outer second coil intersect, and in the radial direction, the two intersecting conductors and the inner coil are in positions overlapping each other. The angle sensor according to claim 2.

5. Taking the inner coil as the inner first coil, the plurality of inner coils include an inner second coil which is the inner coil adjacent to the inner first coil in the circumferential direction, and two conductors connecting the inner first coil and the inner second coil intersect, and in the radial direction, the two intersecting conductors and the outer coil are in positions overlapping each other. The angle sensor according to claim 2.

6. Comprising an outer conductor forming the plurality of outer coils and an inner conductor forming the plurality of inner coils, the outer conductor has a folded-back portion in the circumferential direction, and the inner conductor has a folded-back portion in the circumferential direction. The angle sensor according to any one of claims 1 to 5.

7. The outer conductor and the inner conductor are each a single conductor. The angle sensor according to claim 6.

8. The cylinder has a wall separating the outer coil and the inner coil in the radial direction. The angle sensor according to any one of claims 1 to 7.

9. The cylinder includes a space that is open in the radial direction, and the plurality of outer coils and the plurality of inner coils are arranged in the space that is open in the radial direction. The angle sensor according to any one of claims 1 to 8.

10. One of the areas surrounded by the plurality of outer coils and the area surrounded by the plurality of inner coils is larger than the other. The angle sensor according to any one of claims 1 to 9.

11. The angle sensor according to any one of claims 1 to 10, further comprising a rotating body, wherein in the radial direction, the rotating body is arranged on the inner surface side or the outer surface side of the cylinder.

12. In the radial direction, the plurality of outer coils and the plurality of inner coils face the rotating body. The angle sensor according to claim 11.

13. The rotating body has a plurality of conductors arranged in the circumferential direction. The angle sensor according to claim 11 or 12.

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