Angle sensor

Abstract

An angle sensor (1) comprises a rotor (2) and a stator (3). The rotor (2) includes a cylinder (10) and a plurality of conductor bodies (5) fixed to the cylinder (10). The stator (3) includes a plurality of coils (20) arranged in the circumferential direction of the cylinder (10). The rotor (2) and the plurality of coils (20) face each other in the radial direction of the cylinder (10). Parts of conductive wires (30) that are led out from the coils (20) are positioned in the stator (3).

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] Japanese Patent Application Laid-Open No. 2019-200106

[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 rotor having a cylinder, a plurality of conductors fixed to the cylinder, and a stator having a plurality of coils arranged circumferentially around the cylinder, wherein the rotor and the plurality of coils face each other in the radial direction of the cylinder, and a portion of the conductor wire drawn from the coil is positioned in the stator.

[0007] 8 is a diagram schematically showing the configuration of an angle sensor according to an embodiment of the present invention, and is a partially transparent perspective view schematically showing the internal configuration through some members of the angle sensor. FIG. 9 is a perspective view schematically showing the configuration of the angle sensor. FIG. 10 is a front view schematically showing the configuration of the angle sensor. FIG. 11 is a side view schematically showing the configuration of the angle sensor. FIG. 12 is a perspective view schematically showing the configuration of a stator. FIG. 13 is a front view schematically showing the configuration of a stator. FIG. 14 is a perspective view showing an example of a coil structure formed by a plurality of coils. FIG. 15 is a diagram schematically showing the configuration of the coil structure shown in FIG. 7. FIG. 16 is an enlarged front view showing an enlarged positioning region on a side surface of the stator and its vicinity. FIG. 17 is an enlarged perspective view showing an enlarged positioning region on a side surface of the stator and its vicinity. FIG. 18 is an enlarged front view showing an enlarged positioning region on a side surface of the stator and its vicinity, where the ends of the magnet wires are fixed in a first alternative fixing form. FIG. 19 is an enlarged front view showing an enlarged positioning region on a side surface of the stator and its vicinity, where the ends of the magnet wires are fixed in a second alternative fixing form. FIG. 19 is a perspective view showing a modified example of a stator.

[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 through some of the components of the angle sensor 1. FIG. 2 is a perspective view schematically illustrating the configuration of the angle sensor 1, FIG. 3 is a front view schematically illustrating the configuration of the angle sensor 1, and FIG. 4 is a side view schematically illustrating the configuration of the angle sensor 1. As shown in FIGS. 1 to 4, the angle sensor 1 includes a rotor 2 and a stator 3. The rotor 2 includes a cylinder 10 and a plurality of conductors 5 fixed to the cylinder 10. The stator 3 includes a plurality of coils 20 arranged in the circumferential direction of the cylinder 10. The rotor 2 and the plurality of coils 20 face each other in the radial direction of the cylinder 10. A portion of the conductor 30 drawn from the coil 20 is positioned in the stator 3. The configuration of the angle sensor 1 will be described in detail below. The axis x is the rotation axis of the angle sensor 1. The radial direction is a direction perpendicular to the axis x.

[0009] 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 in FIGS. 2 to 4, the rotor 2 and the stator 3 are shown 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 10 of the rotor 2 is a cylindrical member extending along the axis x. Note that FIG. 1 shows the interior of the cylinder 10 in a see-through manner. The cylinder 10 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 10 of the rotor 2 has an inner circumferential surface 11, which is a cylindrical surface extending along a cylindrical surface with the axis x as its central axis, and an outer circumferential surface 12, which is a cylindrical surface facing away from the inner circumferential surface 11 on the radially outer side (hereinafter also referred to as the "outer peripheral side"). The cylinder 10 also has end faces 13 and 14, which are surfaces facing in the respective directions in which the axis x extends. The inner circumferential surface 11 and the outer circumferential surface 12 extend between the end faces 13 and 14. The angle sensor 1 is applied to, for example, a motor, and the motor shaft passes through the inner circumferential surface 11 of the cylinder 10 of the rotor 2, and the rotor 2 is fixed to the shaft. The cylinder 10 is made of, for example, a resin material, a non-magnetic material, a non-conductive material, etc. The non-magnetic material may also be non-conductive.

[0011] As shown in FIG. 1 , the tube 10 has a conductor structure 4. The conductor structure 4 is fixed to the tube 10. 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 10. 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 within a tube 10, for example, as shown in Fig. 1. The entire metal bodies 5 may be embedded within the tube 10, or a portion of each metal body 5 may be exposed on the surface of the tube 10. The plurality of metal bodies 5 may also be attached to the surface of the tube 10, for example, to the outer peripheral surface 12. In this case, a portion of the metal body 5 may be embedded within the tube 10.

[0013] FIG. 5 is a perspective view schematically illustrating the configuration of the stator 3, and FIG. 6 is a front view schematically illustrating the configuration of the stator 3. As shown in FIGS. 1 to 6, the stator 3 has a cylindrical portion 41 that is a cylindrical part corresponding to the cylinder 10 of the rotor 2. The cylindrical portion 41 forms a space capable of accommodating the rotor 2 therein and has an inner circumferential surface 42 that defines this space. The inner circumferential surface 42 is a surface that follows a cylindrical surface extending along the axis x and faces the outer circumferential surface 12 of the cylinder 10 of the rotor 2 with an annular gap therebetween. The inner circumferential surface 42 is, for example, a cylindrical surface that extends along a cylindrical surface with the axis x as its central axis.

[0014] As shown in FIGS. 1 to 6 , the stator 3 has an attachment portion 44 that is attached to an external device as an application target. As shown in FIGS. 1 to 6 , the attachment portion 44 is provided, for example, on the outer peripheral surface 43 of the cylindrical portion 41 and protrudes outward from the cylindrical portion 41. The outer peripheral surface 43 of the cylindrical portion 41 is a cylindrical surface facing away from the inner peripheral surface 42. The attachment portion 44 has a through hole 44a through which a fixing member such as a bolt is passed, so that the attachment portion 44 can be attached to an external device by the fixing member. The stator 3 has, for example, three attachment portions 44. However, the number of attachment portions 44 of the stator 3 is not limited thereto. As shown in FIGS. 1 to 6 , the stator 3 has a holding portion 45 that houses a substrate 8 serving as an electric circuit device having a circuit unit and a computing unit. 1 to 6, the holding portion 45 extends from the outer peripheral surface 43 of the cylindrical portion 41 along the axis x in one direction of the axis x. The holding portion 45 is also provided between the multiple mounting portions 44 in the circumferential direction.

[0015] As shown in FIGS. 1 to 6 , the stator 3 also includes a plurality of protrusions 46. As shown in FIGS. 2 to 6 , the protrusions 46 protrude toward the rotor 2. As shown in FIG. 6 , the protrusions 46 are portions that protrude radially inward (hereinafter also referred to as the "inner peripheral side") from the inner peripheral surface 42 of the cylindrical portion 41. The protrusions 46 are provided on the inner peripheral surface 42, for example, at equal or approximately equal angular intervals around the axis x. The protrusions 46 have, for example, a rectangular or approximately rectangular cross section perpendicular to the radial direction. Note that the cross-sectional shape of the protrusions 46 is not limited to a rectangular shape and may be other shapes. Each protrusion 46 has a surface 46 a facing the inner peripheral side, and the surface 46 a faces the outer peripheral surface 12 of the cylinder 10 of the rotor 2 with an annular gap therebetween. The surfaces 46 a of the respective protrusions 46 are, for example, arranged along a cylindrical surface whose central axis is the axis x. 6, the protruding portion 46 includes, for example, a connecting portion 46b that connects to the cylindrical portion 41 and an end portion 46c on the rotor 2 side. A surface 46a is formed on the end portion 46c. Furthermore, as shown in FIG. 5, the end portion 46c protrudes further in the circumferential direction and the direction of the axis x than the connecting portion 46b, and an annular groove is formed between the connecting portion 46b and the cylindrical portion 41.

[0016] The stator 3 is, for example, integrally molded from the same material, and each component of the stator 3 is connected together. The stator 3 is an insulating member, for example, a resin member. The stator 3 is made of, for example, a resin material, a non-magnetic material, or a non-conductive material. The non-magnetic material may be non-conductive. Any or all of the components of the stator 3 may be formed as separate bodies. In this case, the stator 3 is formed by assembling the components formed as separate bodies by adhesive or the like.

[0017] The coil 20 is made of a conductive conductor 30. The multiple coils 20 are, for example, lined up and connected in a circumferential direction around the axis x. As schematically shown in FIG. 1 , the multiple coils 20 form a cylindrical shape (hereinafter referred to as a "coil structure") 6 extending annularly around the axis x. The coil structure 6 is a shape formed by arranging the multiple coils 20. In the coil structure 6, the multiple coils 20 are, for example, lined up annularly so as to be aligned along an annular surface around the axis x. The multiple coils 20 are, for example, lined up annularly so as to be aligned along a cylindrical surface with the axis x as the central axis. Furthermore, each coil 20 has, for example, a shape that surrounds a space. Furthermore, each coil 20 has, for example, a shape that the space surrounded by each coil 20 follows an annular surface around the axis x.

[0018] FIG. 7 is a perspective view showing an example of a coil structure 6 formed by a plurality of coils 20. FIG. 8 is a diagram schematically showing the configuration of the coil structure 6 shown in FIG. 7. The coil 20 is, for example, a coil formed by winding a magnet wire 30, which is an example of a conductive conductor 30. As shown in FIGS. 1, 7, and 8, for example, the coil 20 is formed by winding the magnet wire 30 around a plurality of protrusions 46. The coil 20 has an annular shape wound around the radial direction r of the cylinder 10 and surrounds a planar space facing the radial direction. A plurality of coils 20 are formed in a row around the axis x on the cylinder portion 41 of the stator 3 to form the coil structure 6. Note that the conductive conductor 30 forming the coil 20 is not limited to a magnet wire.

[0019] As shown in Figures 7 and 8, the coil structure 6 has two pieces (hereinafter referred to as coil structure pieces) 6a and 6b. The coil structure piece 6a is formed by a plurality of coils 20a, which are the coil 20 described above, connected in series in an annular shape. Similarly, the coil structure piece 6b is formed by a plurality of coils 20b, which are the coil 20 described above, connected in series in an annular shape. That is, in the coil structure piece 6a and the coil structure piece 6b, a plurality of annular coils 20a and 20b are arranged in the circumferential direction, respectively. Note that the coil structure piece 6a and the coil structure piece 6b are coated with, for example, an insulating material (an insulating film or coating) and are electrically insulated from each other. As shown in Figures 7 and 8, the coil structure piece 6a and the coil structure piece 6b overlap in the radial direction to form the coil structure 6. In the coil structure pieces 6a and 6b, a portion of the space surrounded by the coil 20a is offset in the circumferential direction from a portion of the space surrounded by the coil 20b, and another portion of the space surrounded by the coil 20a is overlapped in the circumferential direction. Specifically, the space surrounded by the coil 20a is offset in the circumferential direction from the space surrounded by the coil 20b by half the width of the space surrounded by the coil 20a. The number of coils 20a and 20b in each of the coil structure pieces 6a and 6b corresponds to the axial multiplier angle set for the angle sensor 1. The number of coil structure pieces 6a and 6b also corresponds to the number of detection signals output by the coil structure 6.

[0020] 4 and 8 , a magnet wire 30 as a conductor 30 is wound around each of the protrusions 46 in the radial direction r, and a plurality of annular coils 20 are formed around the plurality of protrusions 46 in the radial direction r, thereby forming a coil structure 6 in the stator 3. Specifically, the magnet wire 30 is wound around the connecting portion 46b of the protrusions 46. For example, the coil structure pieces 6a, 6b are formed by winding one magnet wire 30a, 30b around the plurality of protrusions 46 of the cylindrical portion 41, respectively. Specifically, for example, the magnet wire 30a, 30b is wound around the protruding portions 46 alternately from one side in the axial x direction and the other side in the axial x direction for every two adjacent protruding portions 46 toward one side in the circumferential direction, and then turned back after making one full turn around the cylindrical portion 41. The magnet wire 30a, 30b is then wound around the protruding portions 46 again toward the other side in the circumferential direction, to form the coil structure pieces 6a, 6b. In this case, each of the coils 20a, 20b is formed around two of the protruding portions 46. The coil structure pieces 6a and 6b are offset from each other by one of the protruding portions 46 in the circumferential direction. Note that the coils 20a, 20b are not limited to being formed around two of the protruding portions 46, and may be formed around other numbers of protruding portions. Furthermore, although the magnet wire 30 (30a, 30b) is described as being wound around one turn around the cylindrical portion 41, the winding pattern of the magnet wire 30 is not limited to this, and the magnet wire 30 may be wound around two or more turns. In other words, the coil formed by winding the magnet wire 30 may have, for example, one layer or multiple layers, such as two, three, four, or five layers, in the radial direction. 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.

[0021] Note that ends 31, 32, which are portions connected to both ends of the magnet wire 30 wound around the protrusions 46 to form multiple coils 20, are drawn out from the coil 20. For example, as shown in Fig. 8, ends 31a, 32a, which are portions connected to both ends of the magnet wire 30a, and ends 31b, 32b, which are portions connected to both ends of the magnet wire 30b, are drawn out from one coil 20a, 20b, respectively. As shown in Fig. 8, as an example, the ends 31a, 32a of the magnet wire 30a are drawn out from the coil 201a formed on the first protrusion 461 and the second protrusion 462, and the ends 31b, 32b of the magnet wire 30b are drawn out from the coil 201b formed on the second protrusion 462 and the third protrusion 463.

[0022] As described above, a portion of the conductor 30 drawn out from the coil 20 is positioned in the stator 3. Specifically, the portion of the conductor 30 drawn out from the coil 20 passes through one of one or more paths defined on the outer periphery. Furthermore, the portion of the conductor 30 drawn out from the coil 20 is fixed to the stator 3. Specifically, for example, the portion of the conductor 30 drawn out from the coil 20 is the end portions 31, 32 that are connected to both ends of the magnet wire 30 described above, and as shown in FIGS. 1 to 3, 5, and 6, the end portions 31, 32 of the magnet wire 30 are positioned by a positioning structure 50 formed on the stator 3. The specific configuration of the positioning structure 50 formed on the stator 3 will be described later.

[0023] 2 and 5, a substrate 8 is fixed to the holding portion 45 of the stator 3. The substrate 8 is, for example, a printed circuit board (PCB). The substrate 8 has, for example, electronic components 8a, wiring 8b, and lands 8c as terminals. Ends 31 and 32 of a magnet wire 30 drawn from the coil 20 are fixed to the lands 8c, electrically connecting the magnet wire 30 (coil 20) and each component of the substrate 8.

[0024] The rotor 2 and the stator 3 form an inductive angle sensor, and the multiple coils 20 form detection coils. A magnetic space or magnetic gap is formed between the rotor 2 and the stator 3. For example, in the angle sensor 1, a radially directed magnetic flux whose magnitude periodically changes acts on the multiple coils 20. Specifically, the stator 3 is provided with an excitation circuit 7 (see FIG. 4 ), which is a magnetic circuit that generates a periodically changing magnetic flux acting on each of the multiple coils 20. Meanwhile, the multiple metal bodies 5 are arranged circumferentially around the axis x as described above, and cross the magnetic flux generated by the excitation circuit 7 as the rotor 2 rotates. Furthermore, the projection of the metal body 5, which has a portion extending along the axis x, onto the coils 20 in the radial direction moves as the rotor 2 rotates. Therefore, the magnetic flux from the excitation circuit 7 acting on each of the multiple coils 20 is affected by eddy currents generated in the metal bodies 5 and cancels out, periodically changing as the rotor 2 rotates. As a result, in the plurality of coils 20, an electromotive force is generated by electromagnetic induction which varies with the rotation of the rotor 2, and signals which vary with the rotation of the rotor 2 are detected from the plurality of coils 20. Based on the detection signals from the plurality of coils 20, the rotation angle of the rotor 2 is detected in an external electric circuit device.

[0025] Next, the configuration of the positioning structure 50 formed on the stator 3 will be specifically described.

[0026] As shown in FIGS. 2 to 6 , the positioning structure 50 is provided on a side surface 47 of the stator 3. The side surface 47 is a surface that connects the inner peripheral surface 42 and the outer peripheral surface 43 in the radial direction and is an annular surface facing one side of the tubular portion 41 in the direction of the axis x. The side surface 47 extends, for example, along a plane or a substantially flat surface. As shown in FIGS. 2 , 3 , 5 , and 6 , the side surface 47 extends to a portion of the retaining portion 45 that protrudes from the outer peripheral surface 43 of the tubular portion 41. Specifically, the side surface 47 includes a surface 45a that faces the other side of the retaining portion 45 in the direction of the axis x. As shown in FIGS. 5 and 6 , the surface 45a is, for example, a rectangular or substantially rectangular surface. The shape of the surface 45a is not limited to a rectangle and may be other shapes. In this way, the side surface 47 protrudes outward at the position of the retaining portion 45.

[0027] As shown in FIGS. 2 to 6 , the holding portion 45 has a support surface 45b that faces in the radial direction. The support surface 45b is a surface that supports the substrate 8. The support surface 45b extends from the outer peripheral end of the side surface 45a of the side surface 47 to the other side in the direction of the axis x. The support surface 45b extends, for example, along a plane or a substantially plane. As shown in FIG. 4 , the stator 3 has a side surface 48. The side surface 48 is a surface facing away from the side surface 47 in the direction of the axis x, and is an annular surface facing the other side of the cylindrical portion 41 in the direction of the axis x, and extends between the inner peripheral surface 42 and the outer peripheral surface 43.

[0028] 2 to 6 , the positioning structure 50 is specifically formed on the side surface 47 of the stator 3, between the support surface 45b of the retaining portion 45 and a portion of the inner circumferential surface 42 that faces away from the support surface 45b on the inner circumferential side. In other words, the positioning structure 50 is formed in a positioning region 47a that is a portion that includes the surface 45a and the portion of the side surface 47 between the surface 45a and the inner circumferential surface 42.

[0029] 9 is an enlarged front view showing the positioning region 47a and its vicinity on the side surface 47 of the stator 3, and FIG. 10 is an enlarged perspective view showing the positioning region 47a and its vicinity. The positioning structure 50 is configured to fix the ends 31, 32 of the conducting wire 30 on the outer circumferential side of the plurality of coils 20 by passing them through one or more paths.

[0030] 9 and 10 , the positioning structure 50 has a plurality of protrusions 51. The plurality of protrusions 51 are provided in the positioning region 47 a. The plurality of protrusions 51 are portions that protrude from the side surface 47 to one side in the direction of the axis x. The plurality of protrusions 51 are provided so that at least one of the protrusions 51 stably supports the ends 31, 32 of the conducting wire 30 drawn from the coil 20, the end of which is fixed to the land 8 c of the substrate 8. For example, the plurality of protrusions 51 are provided so that one surface (hereinafter referred to as the "side surface") 33a, 34a of the ends 31, 32 of the conductor 30 drawn out from the coil 20 contacts one protrusion 51 facing in one circumferential direction, and the other surface (hereinafter referred to as the "side surface") 33b, 34b of the ends 31, 32 of the conductor 30 contacts another protrusion 51 facing in the other circumferential direction, applying tension to the ends 31, 32 of the conductor 30 and stably supporting the ends 31, 32 of the conductor 30 by these two protrusions 51. Note that the one side surface 33a, 34a of the ends 31, 32 of the conductor 30 and the other side surface 33b, 34b of the ends 31, 32 face in opposite directions in the circumferential direction, with the one side surface 33a, 34a facing in one circumferential direction and the other side surface 33b, 34b facing in the other circumferential direction. In addition, the multiple protrusions 51 may be provided so that the ends 31, 32 of the conductor 30 are equally stably supported by one protrusion 51, or so that the ends 31, 32 of the conductor 30 are equally stably supported by three or more protrusions 51.

[0031] As shown in Figures 9 and 10, the multiple protrusions 51 have, for example, a cylindrical or approximately cylindrical shape extending in a direction perpendicular or approximately perpendicular to the side surface 47. The shape of the multiple protrusions 51 is not limited to a cylindrical shape and may be other shapes. For example, the multiple protrusions 51 may be prismatic. As described above, the multiple protrusions 51 are arranged so that one or more of the protrusions 51 stably support the ends 31, 32 of the conducting wire 30. The arrangement of the multiple protrusions 51 shown in Figures 9 and 10 is one example of an arrangement pattern of the multiple protrusions 51, and the arrangement pattern of the multiple protrusions 51 is not limited to this.

[0032] As described above, the multiple protrusions 51 can form a stable path for the ends 31, 32 of the conductor 30 between the substrate 8 and the coil 20. Furthermore, multiple paths can be formed by selecting one or more protrusions 51 that support the ends 31, 32 of the conductor 30 from the multiple protrusions 51. Therefore, a stable path for the ends 31, 32 of the conductor 30 can be selected depending on various configurations of the substrate 8 and the coil 20.

[0033] 9 and 10 show a specific example of an arrangement pattern of the plurality of protrusions 51. In this example, the ends 31a and 32a of the magnet wire 30a forming the coil structure piece 6a are drawn out from the vicinity of one protrusion 461 located near the holding portion 45, and the ends 31b and 32b of the magnet wire 30b forming the coil structure piece 6b are drawn out from the vicinity of one protrusion 462 located near the holding portion 45, and the plurality of protrusions 51 stably fix these. In addition, the positioning structure 50 of this example has seven protrusions 511 to 517.

[0034] 9 and 10 , the three protrusions 511, 512, and 513 are provided radially outward from the protrusion 461 of the stator 3. One protrusion 511 is provided near the inner circumferential surface 42 of the cylindrical portion 41 of the stator 3, and is provided near the protrusion 461 of the stator 3. One protrusion 513 is provided near the support surface 45b of the holding portion 45 or the substrate 8, and the other protrusion 512 is provided between the protrusions 511 and 513. All three protrusions 511, 512, and 513 are provided at different positions in the circumferential direction. Different positions in the circumferential direction mean positions on different radial lines.

[0035] 9 and 10 , one protrusion 514 is located at the center or approximately the center of the positioning region 47 a. The center of the positioning region 47 a is the center position in the circumferential and radial directions. Also, as shown in FIGS. 9 and 10 , the three protrusions 515, 516, and 517 are arranged symmetrically or approximately symmetrically with respect to the three protrusions 511, 512, and 513 with respect to a radial line passing through the central or approximately centrally located protrusion 514. That is, the three protrusions 515, 516, and 517 are located radially outward of the protrusion 462 of the stator 3. As shown in FIGS. 9 and 10 , the protrusion 462 of the stator 3 is the protrusion 462 adjacent to the protrusion 461 on one circumferential side. One protrusion 515 is located near the inner circumferential surface 42 of the cylindrical portion 41 and near the protrusion 462 of the stator 3. One protrusion 517 is provided near the support surface 45b of the holder 45 or the substrate 8, and the other protrusion 516 is provided between the protrusions 515 and 517. All three protrusions 515, 516, and 517 are provided at different positions in the circumferential direction.

[0036] 9 and 10 , ends 31a and 32a of magnet wire 30a drawn from coil 201a, which is one of the coils of coil structure piece 6a, intersect and are hung on protruding portion 511 located near protruding portion 461 of stator 3. That is, end 31a is drawn from coil 201a from one circumferential side of protruding portion 511 and hung on protruding portion 511 so that one side surface 33a of end 31a contacts the side surface of protruding portion 511 from the other circumferential side. On the other hand, end 32a is drawn from coil 201a from the other circumferential side of protruding portion 511 and hung on protruding portion 511 so that the other side surface 33b of end 32a contacts the side surface of protruding portion 511 from one circumferential side. As a result, end 31a and end 32a intersect near protruding portion 461 of stator 3, on the inner circumferential side of protruding portion 511. As a result, the magnet wire 30a surrounds the protruding portion 461 and the adjacent protruding portion 462, and the coil 201a is formed around these two protruding portions 461, 462. Because the protruding portion 511 is provided near the protruding portion 461 of the stator 3, the coil 201a does not spread significantly toward the protruding portion 511, and the coil 201a is formed in the same or approximately the same shape as the other coils 20. Therefore, it is possible to prevent the area surrounded by the coil 201a adjacent to the ends 31a, 32a of the magnet wire 30a from being different from the area surrounded by the other coils 20, and it is possible to prevent variations in the detection signals output by each coil 20.

[0037] 9 and 10 , the end 31 a of the magnet wire 30 a is hooked on the protrusion 517 on the outer circumferential side of the protrusion 511 so that the other side surface 33 b of the end 31 a contacts the side surface of the protrusion 517 from one circumferential side. The end 31 a of the magnet wire 30 a is then fixed to a predetermined one of the multiple lands 8 c of the substrate 8. In this way, the two protrusions 511, 517 form a path for the end 31 a of the magnet wire 30 a that extends in the radial direction. Because the end 31 a of the magnet wire 30 a is hooked on the protrusions 511, 517 so as to have tension, the end 31 a of the magnet wire 30 a does not slacken and is stably fixed in this path.

[0038] 9 and 10 , the end 32 a of the magnet wire 30 a is hooked onto the protrusion 512 on the outer circumferential side of the protrusion 511 so that one side surface 33 a of the end 32 a contacts the side surface of the protrusion 512 from the other circumferential side. The end 32 a of the magnet wire 30 a is then fixed to a predetermined one of the multiple lands 8 c of the substrate 8. In this way, the two protrusions 511, 512 form a path for the end 32 a of the magnet wire 30 a that extends in the radial direction. Because the end 32 a of the magnet wire 30 a is hooked onto the protrusions 511, 512 so as to be under tension, the end 32 a of the magnet wire 30 a does not slacken and is stably fixed along this path.

[0039] 9 and 10 , the ends 31b and 32b of the magnet wire 30b drawn out from the coil 201b are hung on the protrusions 515 and 513 and the protrusions 515 and 516, respectively, so as to be symmetrical with the ends 31a and 32a of the magnet wire 30a described above, respectively, with respect to the central plane, and are fixed to the corresponding lands 8c, similar to the ends 31a and 32a of the magnet wire 30a described above. This forms a stable path for the ends 31b and 32b of the magnet wire 30b directed in the radial direction. Therefore, similar to the coil 201a, it is possible to prevent the area surrounded by the coil 201b adjacent to the ends 31b and 32b of the magnet wire 30b from differing from the area surrounded by the other coils 20, and it is possible to prevent variations in the detection signals output by each coil 20.

[0040] As described above, the positioning structure 50 can stably fix the ends 31, 32 of the magnet wire 30 that form the coil 20. This can prevent the ends 31, 32 of the magnet wire 30 from moving, causing variations in the detection signal output by the coil 20. This can reduce variations in the detection accuracy of the angle sensor 1, and improve the detection accuracy of the angle sensor 1.

[0041] Furthermore, as described above, the positioning structure 50 can prevent the area surrounded by the coil 20 adjacent to the ends 31, 32 of the magnet wire 30 from differing from the area surrounded by the other coils 20, thereby preventing variations in the detection signals output by the coils 20. In this respect, the positioning structure 50 can also prevent variations in the detection accuracy of the angle sensor 1, thereby improving the detection accuracy of the angle sensor 1.

[0042] Furthermore, since the positioning structure 50 can form multiple paths for the ends 31, 32 of the magnet wire 30, it is possible to provide optimal paths for the ends 31, 32 of the magnet wire 30 depending on various configurations such as the shape of the protrusion 46 of the stator 3 and the shape of the substrate 8.

[0043] 9 and 10 , the positioning structure 50 can also be used to secure the ends 7a and 7b of the conductor wires extending from the excitation circuit 7, which are connected to both ends of the conductor wires forming the excitation circuit 7. As shown in FIGS. 9 and 10 , for example, the ends 7a and 7b of the excitation circuit 7 are pulled out from between the protrusions 461 and 462 of the stator 3, hooked around one side of the protrusion 514 in the circumferential direction, and secured to the corresponding lands 8c. The ends 7a and 7b of the excitation circuit 7 are supported by the protrusion 514 under tension, similar to the ends 31 and 32 of the magnet wire 30. In this way, the ends 7a and 7b of the conductor wires extending from the excitation circuit 7 can also be stably secured by the positioning structure 50. Furthermore, the positioning structure 50 can set various paths for the ends 7a and 7b of the conductor wires extending from the excitation circuit 7 between the excitation circuit 7 and the substrate 8.

[0044] In this way, the angle sensor 1 according to the embodiment of the present invention can improve detection accuracy.

[0045] Next, a first alternative fixing configuration will be described for the ends 31 a, 32 a of the magnet wire 30 a drawn out from the coil 201 a and the ends 31 b, 32 b of the magnet wire 30 b drawn out from the coil 201 b. Fig. 11 is an enlarged front view showing, in enlarged form, a positioning region 47 a and its vicinity on a side surface 47 of the stator 3 to which the ends 31 a, 32 a of the magnet wire 30 a and the ends 31 b, 32 b of the magnet wire 30 b are fixed in the first alternative fixing configuration.

[0046] 11 , in the first other fixing configuration, the ends 31 a, 32 a of the magnet wire 30 a drawn out from the coil 201 a first cross each other and are hung on the protrusion 511 located near the protrusion 461 of the stator 3, similar to the fixing configuration shown in FIGS. 9 and 10 described above. Therefore, also in the first other fixing configuration, it is possible to prevent the area surrounded by the coil 201 a adjacent to the ends 31 a, 32 a of the magnet wire 30 a from being different from the area surrounded by the other coils 20, and it is possible to prevent variations in the detection signals output by the coils 20.

[0047] 11 , the end 31 a of the magnet wire 30 a is pulled radially on the outer circumferential side of the protrusion 511 so that one side surface 33 a of the end 31 a contacts the side surface of the protrusion 512 from the other circumferential side, and the end 31 a of the magnet wire 30 a is fixed to a predetermined one of the multiple lands 8 c of the substrate 8. In this way, the two protrusions 511, 512 form a path for the end 31 a of the magnet wire 30 a that extends radially. The end 31 a of the magnet wire 30 a is hooked on the protrusion 511 so as to have tension, and is in contact with the protrusion 512, so that the end 31 a of the magnet wire 30 a does not slacken and is stably fixed in this path.

[0048] 11 , like the end 31a, the end 32a of the magnet wire 30a is pulled radially on the outer circumferential side of the protrusion 511 so that the other side surface 33b of the end 32a contacts the side surface of the protrusion 512 from one circumferential side, and the end 32a of the magnet wire 30a is fixed to a predetermined one of the multiple lands 8c of the substrate 8. In this way, the two protrusions 511, 512 form a path for the end 32a of the magnet wire 30a that extends radially. The end 32a of the magnet wire 30a is hooked on the protrusion 511 so as to have tension, and is in contact with the protrusion 512, so that the end 32a of the magnet wire 30a does not slacken and is stably fixed in this path.

[0049] 11, the ends 31b and 32b of the magnet wire 30b drawn out from the coil 201b are respectively hooked onto and contact the protrusions 515 and 516 of the ends 31a and 32a of the magnet wire 30a described above, so as to be symmetrical with respect to the central plane with respect to the ends 31a and 32a of the magnet wire 30a described above, and are fixed to the corresponding lands 8c. Therefore, similar to the coil 201a, the area surrounded by the coil 201b adjacent to the ends 31b and 32b of the magnet wire 30b can be prevented from differing from the area surrounded by the other coils 20, and variations in the detection signals output by each coil 20 can be prevented. Furthermore, the ends 31b and 32b of the magnet wire 30b are stably fixed without loosening along this path.

[0050] 9 and 10. Furthermore, in order to prevent variations in the detection signals output by the coils, it is preferable that the ends of the magnet wires drawn from the same coil be as close as possible, and it is even more preferable that they overlap. In the first alternative fixing configuration, as shown in FIG. 11, the ends 31 a and 32 a of the magnet wire 30 a drawn from the coil 201 a are close to each other, and similarly, the ends 31 b and 32 b of the magnet wire 30 b drawn from the coil 201 b are close to each other. This also prevents variations in the detection signals output by the coils 20, thereby further improving the detection accuracy of the angle sensor 1.

[0051] In the first other fixing form, the ends 7a and 7b of the conductors that form the excitation circuit 7 and are drawn out from the excitation circuit 7 are also stably fixed by the positioning structure 50, similar to the ends 7a and 7b of the conductors of the excitation circuit 7 shown in Figures 9 and 10 described above.

[0052] Next, a second alternative fixing configuration will be described for the ends 31 a, 32 a of the magnet wire 30 a drawn out from the coil 201 a and the ends 31 b, 32 b of the magnet wire 30 b drawn out from the coil 201 b. Fig. 12 is an enlarged front view showing, in enlarged form, a positioning region 47 a and its vicinity on a side surface 47 of the stator 3 to which the ends 31 a, 32 a of the magnet wire 30 a and the ends 31 b, 32 b of the magnet wire 30 b are fixed in the second alternative fixing configuration.

[0053] 12, in the second other fixing configuration, the ends 31a, 32a of the magnet wire 30a drawn out from the coil 201a first cross each other and are hung on the protrusion 511 located near the protrusion 461 of the stator 3, similar to the fixing configuration shown in Figures 9 and 10 described above. Therefore, in the second other fixing configuration, it is possible to prevent the area surrounded by the coil 201a adjacent to the ends 31a, 32a of the magnet wire 30a from being different from the area surrounded by the other coils 20, and it is possible to prevent variations in the detection signals output by the coils 20.

[0054] 12 , the end 31 a of the magnet wire 30 a is pulled out from the coil 201 a from one circumferential side and is hung on the protruding portion 511 on the other circumferential side of the protruding portion 511 so that one side surface 33 a of the end 31 a contacts the side surface of the protruding portion 511 from the other circumferential side. Furthermore, the end 31 a of the magnet wire 30 a is hung on the protruding portion 512 on the outer circumferential side of the protruding portion 511 so that the other side surface 33 b of the end 31 a contacts the side surface of the protruding portion 512 from one circumferential side. The end 31 a of the magnet wire 30 a is then fixed to a predetermined one of the multiple lands 8 c of the substrate 8. In this way, the two protruding portions 511, 512 form a path for the end 31 a of the magnet wire 30 a directed radially. Since the end 31a of the magnet wire 30a is hooked around the protrusions 511, 512 so as to be under tension, the end 31a of the magnet wire 30a does not slacken and is stably fixed along this path. Meanwhile, the end 32a of the magnet wire 30a is pulled out from the coil 201a from the other circumferential side and hooked around the protrusion 511 on one circumferential side of the protrusion 511 so that the other side surface 33b of the end 32a contacts the side surface of the protrusion 511 from one circumferential side. Furthermore, the end 32a of the magnet wire 30a is hooked around the protrusion 512 on the outer circumferential side of the protrusion 511 so that one side surface 33a of the end 32a contacts the side surface of the protrusion 512 from the other circumferential side. Then, the end 32a is fixed to a predetermined land 8c. Like the end 31a, the end 32a of the magnet wire 30a is also stably fixed along this path without slackening. The ends 31 a and 32 a intersect in the radial direction between the protrusions 511 and 512 .

[0055] 12, the ends 31b and 32b of the magnet wire 30b drawn out from the coil 201b are hung on the protrusions 515 and 516, respectively, so as to be symmetrical with the ends 31a and 32a of the magnet wire 30a described above with respect to the central plane, and are fixed to the corresponding lands 8c, similar to the ends 31a and 32a of the magnet wire 30a described above. Therefore, similar to the coil 201a, the area surrounded by the coil 201b adjacent to the ends 31b and 32b of the magnet wire 30b can be prevented from differing from the area surrounded by the other coils 20, and variations in the detection signals output by each coil 20 can be prevented. Furthermore, the ends 31b and 32b of the magnet wire 30b are stably fixed without loosening along this path.

[0056] 9 and 10. Furthermore, as described above, it is preferable that the ends of the magnet wires drawn from the same coil are as close as possible to each other, and it is even more preferable that they overlap, in order to prevent variations in the detection signals output by the coils. In the second alternative fixing configuration, as shown in FIG. 12, the ends 31 a and 32 a of the magnet wire 30 a drawn from the coil 201 a cross each other and are close to each other, and similarly, the ends 31 b and 32 b of the magnet wire 30 b drawn from the coil 201 b cross each other and are close to each other. This also prevents variations in the detection signals output by the coils 20, thereby further improving the detection accuracy of the angle sensor 1.

[0057] In the second other fixing form, the ends 7a and 7b of the conductors forming the excitation circuit 7 drawn out from the excitation circuit 7 are also stably fixed by the positioning structure 50, similar to the ends 7a and 7b of the conductors of the excitation circuit 7 shown in Figures 9 and 10 above.

[0058] In the above embodiment, the stator 3 includes the cylindrical portion 41, which is a cylindrical portion, and has a circumferentially continuous annular shape. However, the shape of the stator 3 is not limited to this. FIG. 13 is a perspective view showing a modified example of the stator 3. For example, as shown in FIG. 13 , the stator 3 may be arc-shaped, or may extend only along a partial circumferential section including the positioning structure 50 of the entire circumference of the stator 3. The stator 3 according to the modified example is formed from the same material as the stator 3 described above. The stator 3 according to the modified example is formed, for example, from an insulating resin member. The stator 3 according to the modified example will be specifically described below. Note that, regarding the configuration of the stator 3 according to the modified example, the same reference numerals will be used to designate components that have the same configuration or similar functions as the stator 3 described above, and their description will be omitted.

[0059] As shown in FIG. 13 , the stator 3 according to the modified example has, for example, instead of a cylindrical tubular portion 41, a portion 41A extending in an arc-like or substantially arc-like shape (hereinafter referred to as an arc portion) corresponding to a portion of the circumferential section of the tubular portion 41. The portion of the circumferential section of the tubular portion 41 corresponding to the arc portion 41A includes a positioning structure 50. Like the tubular portion 41, the arc portion 41A also has the positioning structure 50, a positioning region 47a on its side surface 47, and multiple protrusions 51. As shown in FIG. 13 , multiple protrusions 46 are formed side by side on the inner circumferential surface 42 of the arc portion 41A, similar to the stator 3 described above. The arc portion 41A has multiple protrusions 46 formed in the same manner as the portion of the tubular portion 41 corresponding to the arc portion 41A. The stator 3 according to the modified example is provided with a detection coil and an excitation circuit. The detection coil is formed by multiple coils 20, similar to the detection coil (coil structure 6) provided in the stator 3 described above. Specifically, the plurality of coils 20 are arranged so as to form the portions of the coil structure pieces 6a, 6b located in the portion of the cylindrical portion 41 corresponding to the arc portion 41A. In the stator 3 according to the modified example, similar to the plurality of coils 20 in the stator 3 described above, the plurality of coils 20 are formed by winding a conductive member such as a magnet wire around the protrusion 46. Similar to the excitation circuit 7 described above, the excitation circuit is a magnetic circuit that generates a periodically changing magnetic flux that acts on each of the plurality of coils 20 formed in the arc portion 41A.

[0060] Similarly to the stator 3 described above, the stator 3 according to the modified example also has mounting portions 44, which are portions that are attached to an external device as an application target. In the stator 3 according to the modified example, the mounting portions 44 are provided, for example, at two circumferential ends of the arc portion 41A. Furthermore, the stator 3 according to the modified example has an electric circuit device having a circuit unit (not shown), such as an IC, and a calculation unit, mounted or fixed thereto. Specifically, for example, the stator 3 according to the modified example has a holding portion 45 that accommodates the substrate 8, which is the electric circuit device, similar to the stator 3 described above. The holding portion 45 may be provided on one of the circumferential ends of the stator. In this case, a wide area can be secured for providing the excitation circuit and detection coil, thereby contributing to improved detection accuracy. In this case, the positioning region 47a may be provided, for example, on one of the circumferential ends of the stator 3. Furthermore, the electric circuit device and the excitation circuit or detection coil may be adjacent to each other in the circumferential direction. In other words, in the circumferential direction, the electric circuit device is sandwiched between the detection coil or excitation circuit and the mounting portion 44. In this case, the limited space of the stator 3 can be effectively utilized, which contributes to miniaturization of the angle sensor 1.

[0061] In addition, in the above-described stator 3 and the stator 3 according to the modified example, the stator 3 and the electric circuit device may be sealed with an insulating resin member or the like. In this case, the resin can protect the stator 3 and the electric circuit device from foreign matter and the like.

[0062] Furthermore, the stator 3 described above and the stator 3 according to the modified example may also include a connector that can be electrically connected to an external device. The connector may be provided adjacent to the electric circuit device. In this case, the electric circuit device and the connector can be connected via the shortest path, which contributes to miniaturization of the angle sensor 1.

[0063] 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.

[0064] 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.

[0065] REFERENCE SIGNS LIST 1 Angle sensor, 2 Rotor, 3 Stator, 4 Conductor structure, 5 Metal body (conductor), 6 Coil structure, 6a, 6b Coil structure piece, 7 Excitation circuit, 8 Substrate, 8a Electronic component, 8b Wiring, 8c Land, 10 Cylinder, 11 Inner peripheral surface, 12 Outer peripheral surface, 13, 14 End surface, 20, 20a, 20b, 201a, 201b Coil, 30, 30a, 30b Conductor (magnet wire), 31, 31a, 31b, 32, 32a, 32b End, 33a, 33b, 34a, 34b Side, 41 Cylinder portion, 41A Arc portion, 42 Inner peripheral surface, 43 Outer peripheral surface, 44 Mounting portion, 44a Through hole, 45 Holding portion, 45a Side, 45b Support surface, 46, 461, 462 Protrusion, 46a surface, 46b connecting portion, 46c end portion, 47, 48 side surface, 47a positioning region, 50 positioning structure, 51, 511, 512, 513, 514, 515, 516, 517 protrusion, x axis

Claims

1. An angle sensor comprising a rotor having a cylinder and a plurality of conductors fixed to the cylinder, and a stator having a plurality of coils arranged in the circumferential direction of the cylinder, wherein in the radial direction of the cylinder, the rotor and the plurality of coils face each other, and a part of a conducting wire drawn out from the coil is positioned in the stator.

2. The angle sensor according to claim 1, wherein a part of the conducting wire drawn out from the coil passes through one of one or more paths defined on the outer side in the radial direction.

3. The angle sensor according to claim 1 or 2, wherein a part of the conducting wire drawn out radially from the coil is fixed to the stator.

4. The stator includes an inner peripheral surface, an outer peripheral surface, and a side surface connecting the inner peripheral surface and the outer peripheral surface in the radial direction. The side surface of the stator extends in the radial direction, and a part of the conducting wire is fixed to the side surface of the stator. The angle sensor according to any one of claims 1 to 3.

5. The angle sensor according to claim 4, wherein a part of the conducting wire is electrically connected to a substrate fixed to the outer peripheral surface of the stator.

6. A plurality of protrusions are provided on the side surface of the stator. One surface of a part of the conducting wire contacts one of the plurality of protrusions, and the other surface of the part of the conducting wire contacts another of the protrusions. The one surface and the other surface of the part of the conducting wire face in opposite directions. The angle sensor according to claim 4 or 5.

7. The direction of a part of the conducting wire extending from the inner peripheral surface of the stator to the outer peripheral surface of the stator is defined. The angle sensor according to any one of claims 4 to 6.

8. In the radial direction, the plurality of coils are formed on a plurality of protrusions protruding from the stator toward the rotor. The angle sensor according to any one of claims 1 to 7.

9. The parts of the conducting wire connected to both ends of the coil are respectively drawn out. A part of each of the parts of the conducting wire connected to both ends intersects with each other and is positioned in the stator to form the coil. The angle sensor according to claim 1.

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