Angle sensor and rotary device

Abstract

An angle sensor (1) comprises: a rotor (2) having a plurality of protrusions (11) extending in the radial direction; a base (3); and a coated conductor wire (4). The conductor wire (4) is provided on a structural surface (3a) of the base (3) and forms a planar shape having a plurality of undulations in the radial direction. The protrusions (11) face the conductive wire (4) in the axial (x) direction.

Description

Angle sensors and rotating devices

[0001] The present invention relates to an angle sensor and a rotating device, and more particularly to an inductive angle sensor and a rotating device equipped with 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] Therefore, an object of the present invention is to provide an angle sensor and a rotating device that can improve detection accuracy.

[0006] An angle sensor according to one aspect of the present invention comprises a rotor having multiple protrusions extending radially, a base, and a coated conductor, wherein the conductor provided on the surface of the base forms a planar shape having multiple undulations in the radial direction, and the protrusions face the conductor in the direction of the rotation axis.

[0007] 15A and 15B are perspective views each showing a schematic configuration of an angle sensor according to an embodiment of the present invention; FIG. 16A is a side view each showing a schematic configuration of an angle sensor; FIG. 16B is a front view each showing a schematic configuration of a rotor in the angle sensor; FIG. 16C is a front view each showing a schematic configuration of a base in the angle sensor; FIG. 16D is a front view of a rotor showing a modified metal body; FIG. 16E is a front view of a rotor showing a modified metal body; FIG. 16F is a front view of a rotor showing a modified metal body; FIG. 16H is a perspective view of a rotor showing a modified metal body; FIG. 16I is a cross-sectional view of a convexity showing a modified convexity; FIG. 16I is a cross-sectional view of a convexity showing a modified convexity; FIG. 16I is a cross-sectional view of a convexity showing a modified metal body; FIG. 16I is a perspective view of a rotor showing a modified rotor; FIG. 16I is a front view of a base showing a modified base; FIG. 16I is an exploded perspective view of a specific example of a rotating device to which the angle sensor is applied; FIG. 16I is a perspective view showing the tip and its vicinity of the rotating shaft in the rotating device shown in FIG. 15; FIG. 16I is a perspective view of a specific example of a rotor of an angle sensor;

[0008] An embodiment of the present invention will now be described with reference to the accompanying drawings. Note that in the drawings, not all components are designated by reference numerals, and some of the reference numerals of the components may be omitted. FIG. 1 is a perspective view schematically illustrating the configuration of an angle sensor 1 according to an embodiment of the present invention, and FIG. 2 is a side view schematically illustrating the configuration of the angle sensor 1. Also, FIG. 3 is a front view schematically illustrating the configuration of a rotor 2 in the angle sensor 1, and FIG. 4 is a front view schematically illustrating the configuration of a base 3 in the angle sensor 1. As shown in FIGS. 1 to 4 , the angle sensor 1 includes a rotor 2 having multiple protrusions 11 extending radially, a base 3, and a coated conductor 4. The conductor 4 provided on a surface 3a of the base 3 (hereinafter referred to as the structural surface) forms a planar shape with multiple undulations in the radial direction, and the protrusions 11 face the conductor 4 in the direction of the rotation axis (hereinafter referred to as the axis x). The configuration of the angle sensor 1 will now be described in detail. The axis x is the rotation axis of the angle sensor 1. The radial direction is a direction perpendicular to the axis x. Also, Fig. 1 shows the rotor 2 and the base 3 in a predetermined positional relationship. This predetermined positional relationship is an example of the positional relationship between the rotor 2 and the base 3 when the angle sensor 1 is in use and attached to an application object. In the angle sensor 1 in use, the rotor 2 and the base 3 face each other in the direction of the axis x.

[0009] As shown in FIGS. 1 to 3 , the rotor 2 is a disk-shaped member and has a plurality of protrusions 11, which are portions extending radially, as described above. The rotor 2 also has a ring 12, as shown in FIGS. 1 to 3 , for example. The ring 12 is a portion extending annularly around the axis x. The plurality of protrusions 11 are connected to an outer circumferential portion 12a of the ring 12. The ring 12 also has an inner circumferential surface 12b. The inner circumferential surface 12b is a surface facing away from the outer circumferential portion 12a and is a cylindrical surface extending in the direction of the axis x. The inner circumferential surface 12b forms a through hole in the ring 12 extending in the direction of the axis x. As shown in FIGS. 1 to 3 , between two adjacent protrusions 11 among the plurality of protrusions 11, there is an opening 13. The opening 13 forms a space penetrating the rotor 2 in the direction of the axis x between two adjacent protrusions 11. The plurality of protrusions 11 are arranged at equal or approximately equal angular intervals in the circumferential direction around the axis x. The plurality of protrusions 11 have a fan-like or approximately fan-like shape, for example, as shown in FIG.

[0010] The protrusions 11 have a conductor at least in part. The conductor may be any member having a conductive wire material, such as a metal body 10 made of metal. The member having a conductive material is a member capable of generating so-called eddy currents or induced currents (electric currents) within one surface. As an example, the protrusions 11 are entirely made of metal. That is, the entire protrusions 11 are the metal body 10. As an example, the ring 12 is made of the same metal as the multiple protrusions 11, and the rotor 2 is, for example, the integrally formed metal body 10. The multiple protrusions 11 and the ring 12 may be formed separately, and the rotor 2 may be formed by connecting the multiple protrusions 11 and the ring 12. In this case, the ring 12 may be made of a different material from the protrusions 11. For example, the ring 12 may be made of a resin material.

[0011] 1, 2, and 4, the base 3 is a plate-shaped member having portions that face the multiple protrusions 11 of the rotor 2 in the direction of the axis x. The base 3 is an insulating member, for example, a member made of resin. The base 3 is made of, for example, a resin material, a non-magnetic material, a non-conductive material, or the like. Note that the non-magnetic material may be non-conductive.

[0012] The base 3 has an outer peripheral surface and an inner peripheral surface as side surfaces, a front surface, and a back surface. Predetermined structures (e.g., a plurality of protrusions 21 and an annular protrusion 22, which will be described later) are formed on the surface of the base 3. The surface of the base 3 is the structural surface 3a described above. The structural surface 3a faces the rotor 2 in the axial x direction. The structural surface 3a is provided with a plurality of protrusions 21 extending from the base 3 toward the rotor 2. The plurality of protrusions 21 are provided on portions of the structural surface 3a that face the plurality of protrusions 11 or the plurality of openings 13 of the rotor 2 in the axial x direction, and the plurality of protrusions 21 face the plurality of protrusions 11 or the plurality of openings 13 of the rotor 21 in the axial x direction. For example, the plurality of protrusions 21 extend along the axial x, and are positioned so that their radial positions overlap the radial positions of the protrusions 11.

[0013] 1 and 4, for example, the multiple protrusions 21 are formed around the axis x and are arranged at predetermined intervals in the circumferential direction (at equal or approximately equal angular intervals in the illustrated example). Furthermore, as shown in FIGS. 1, 2, and 4, the base 3 has an annular protrusion 22 on its structural surface 3a, radially outward from the multiple protrusions 21. The protrusion 22 is an annular cylindrical portion that protrudes from the structural surface 3a. An excitation circuit 5, which will be described later, is formed in the protrusion 22. Furthermore, as shown in FIGS. 1 and 4, the base 3 has an opening 23 radially inward from the multiple protrusions 21. The opening 23 forms a hole that penetrates the base 3.

[0014] 1, 2, and 4, the base 3 has, for example, a substrate 24. The substrate 24 is, for example, a printed circuit board (PCB). The substrate 24 has electronic components 24a, wiring 24b, terminals 24c, and the like. The electronic components 24a and terminals 24c are arranged on the substrate 24, and wiring 24b is formed to electrically connect the conductors 4, the electronic components 24a, and the terminals 24c. The terminals 24c are used to electrically connect the conductors 4 and the substrate 24 to an external device.

[0015] As described above, the conductor 4 forms a planar shape having multiple undulations in the radial direction on the structural surface 3a of the base 3. The conductor 4 is, for example, a magnet wire. For example, as shown in FIG. 4 , the conductor 4 is wound around each of the protrusions 21, thereby forming a planar shape having multiple undulations in the radial direction. For example, the conductor 4 forms a coil structure 30 on the base 3 by forming multiple annular coils 31 around the axis x along the multiple protrusions 21. The coil structure 30 has a cylindrical planar shape formed by connecting multiple coils 31 in a circumferential direction around the axis x. The conductor is coated with, for example, an insulating material (an insulating film or coating) to provide electrical insulation.

[0016] Specifically, for example, the conductor 4 is wound around the protrusions 21 alternately from one radial side and the other radial side for every two adjacent protrusions 21 toward one circumferential side, turns back after going around the plurality of protrusions 21 once, and then wound around the protrusions 21 once again toward the other circumferential side in the same manner to form the coil structure 30. In this case, each coil 31 is formed around two protrusions 21.

[0017] As shown in FIG. 4 , the angle sensor 1 has two coil structures 30 (30a, 30b). The coil structure 30a has a coil 31a, which is the coil 31 described above, and the coil structure 30b has a coil 31b, which is the coil 31 described above. The coil structures 30a and 30b have the same or substantially the same planar shape. In the base 3, the coil structures 30a and 30b overlap in the direction of the axis x. In the coil structures 30a and 30b, a portion of the space surrounded by the coil 31a and a portion of the space surrounded by the coil 31b are offset in the circumferential direction, and another portion of the space surrounded by the coil 31a and another portion of the space surrounded by the coil 31b overlap in the circumferential direction. Specifically, the space surrounded by the coil 31a is offset in the circumferential direction from the space surrounded by the coil 31b by half the width of the space surrounded by the coil 31a. The number of coils 31 in the coil structure 30 corresponds to the axial multiplier angle set in the angle sensor 1. The number of coil structures 30 also corresponds to the number of detection signals output from the angle sensor 1.

[0018] In the above example, each of the coils 31a and 31b is formed around two protrusions 21. Furthermore, the coil structure 30a and the coil structure 30b are offset from each other by one protrusion 21 in the circumferential direction. However, each of the coils 31a and 31b is not limited to being formed around two protrusions 21, and may be formed around other numbers of protrusions 21. Furthermore, while the case where the conductor 4 is wound around one circumference has been described, the winding pattern of the conductor 4 is not limited to this, and the conductor 4 may be wound around two or more circumferences. In other words, the coil formed by winding the conductor 4 may have, for example, one layer in the radial direction or the axial direction x, or multiple layers, such as two, three, four, or five layers. In this case, the output signal or the signal to be detected (e.g., the amplitude of the signal waveform) can be amplified compared to the case where the coil is wound around one circumference or one layer.

[0019] 1, 2, and 4, an excitation circuit 5 is attached to the protruding portion 22 of the base 3. The excitation circuit 5 is formed by winding a conductor around the protruding portion 22. The conductor is made of a conductive material. The excitation circuit 5 is a magnetic circuit that generates a periodically changing magnetic flux that acts on each of the multiple coils 31, and the conductor forming the excitation circuit 5 is electrically connected to the substrate 24 or the electronic component 24a. The conductor is coated with, for example, an insulating material (an insulating film or coating) and is electrically insulated. Because the conductor is electrically insulated, it can be wound in contact with each other, thereby reducing the area of ​​the winding portion.

[0020] The rotor 2 and base 3 form an inductive angle sensor, and the multiple coils 30 form detection coils. A magnetic space or magnetic gap is formed between the rotor 2 and the base 3. In the angle sensor 1, magnetic flux of periodically changing magnitude directed in the direction of the axis x acts on the multiple coils 31 from the excitation circuit 5. Meanwhile, the multiple protrusions 11 (metal body 10) are arranged circumferentially around the axis x as described above, and cross the magnetic flux generated by the excitation circuit 5 as the rotor 2 rotates. Furthermore, the projection of the protrusions 11 (metal body 10), which have radially extending portions, onto the coils 31 in the direction of the axis x moves as the rotor 2 rotates. Therefore, the magnetic flux from the excitation circuit 5 acting on each of the multiple coils 31, which are multiple radial undulations of the planar shape formed by the conductor 4, periodically changes as the rotor 2 rotates due to the influence of eddy currents generated in the protrusions 11 (metal body 10) canceling each other out. As a result, in the multiple coils 31, an electromotive force is generated by electromagnetic induction that changes with the rotation of the rotor 2, and a signal that changes with the rotation of the rotor 2 is detected from the conductor 4. Based on this detection signal from the conductor 4, the rotation angle of the rotor 2 is detected in the electric circuit device.

[0021] Next, modified examples of the metal body 10 will be described. In the above example, the entire protrusion 11 forms the metal body 10. However, as described above, the protrusion 11 may have a conductor at least in part, and a portion of the protrusion 11 may be the metal body 10. For example, the rotor 2 has multiple metal bodies 10, and each of the multiple metal bodies 10 is attached to a portion of the multiple protrusions 11 facing the base 3 in the axial x direction. Specifically, for example, each of the multiple metal bodies 10 is located in a portion of the multiple protrusions 11 (hereinafter referred to as the "facing portion") 11a. As shown in Figures 2 and 3, the facing portion 11a of the multiple protrusions 11 has a surface facing the base 3 in the axial x direction. This surface of the facing portion 11a is, for example, flat or approximately flat. Furthermore, specifically, for example, each of the multiple metal bodies 10 is embedded inside the multiple protrusions 11, or forms a portion of the surface of the multiple protrusions 11 facing the base 3 and is exposed from the protrusions 11. Furthermore, the plurality of metal bodies 10 may be provided on the surfaces of the plurality of protrusions 11 that face the base 3. The plurality of protrusions 11 and the ring 12 are insulating members. The plurality of protrusions 11 and the ring 12 are made of, for example, a resin material, a non-magnetic material, a non-conductive material, or the like. The non-magnetic material may be non-conductive.

[0022] Fig. 5 is a front view of the rotor 2 showing an example of the metal bodies 10. As shown in Fig. 5, the multiple metal bodies 10 are plate-shaped and have a rectangular or approximately rectangular shape when viewed from the front. Each of the multiple metal bodies 10 is fixed to the opposing portion 11a of the protrusion 11. The multiple metal bodies 10 are positioned so that their radial positions overlap the radial positions of the multiple protrusions 21 of the base 3.

[0023] FIG. 6 is a front view of the rotor 2 showing an example of the metal body 10. As shown in FIG. 6, the multiple metal bodies 10 are plate-shaped. Each of the multiple metal bodies 10 is fixed to the opposing portion 11a of the protrusion 11. The multiple metal bodies 10 are positioned so that their radial positions overlap the radial positions of the multiple protrusions 21 of the base 3. The metal body 10 has an outer peripheral side surface (hereinafter referred to as the end face) 10a facing radially outward and an inner peripheral side surface (hereinafter referred to as the end face) 10b facing radially inward. As shown in FIG. 6, the end face 10a is curved so as to protrude radially outward, and the end face 10b is curved so as to protrude radially inward. Furthermore, both circumferential ends of the end face 10a and both circumferential ends of the end face 10b are connected at acute angles at end portions 10c and 10d, respectively.

[0024] As shown in Figure 6, the width (width W) of the metal body 10 in the circumferential direction of the metal body 10, for example, in a direction perpendicular to a circle of a predetermined radius centered on the axis x, is such that the width of the end portion 10c is smaller than the width of the intermediate portion 10e between the end portions 10c and 10d, and the width of the end portion 10d is smaller than the width of the intermediate portion 10e. For example, the width W of the metal body 10 is greatest at both ends 10f and 10g of the metal body 10 in the radial direction (the width of the intermediate portion 10e (width W0)). The width W decreases circumferentially toward the end portion 10c. Similarly, the width W decreases circumferentially toward the end portion 10d. The end faces 10a and 10b each extend along curved surfaces (e.g., sinusoidal waves) that protrude in opposite directions. In other words, the end faces 10a and 10b extend in directions that intersect and are inclined toward the end portions 10c and 10d, respectively.

[0025] FIG. 7 is a front view of the rotor 2 showing an example of the metal body 10. The multiple metal bodies 10 fixed to the opposing surfaces 11a of the multiple protrusions 11 shown in FIGS. 5 and 6 may be electrically connected to each other via conductive members. Specifically, for example, as shown in FIG. 7, the rotor 2 has a connecting body 14, which is an annular conductive member fixed to the ring 12, and the multiple metal bodies 10 are connected to the connecting body 14 on their radially inner sides. The connecting body 14 is formed, for example, from the same metal as the metal body 10, and the multiple metal bodies 10 and the connecting body 14 are integrated. Note that the connecting body 14 may not be formed from the same metal as the metal body 10 but may be formed from a material having a different conductivity from the metal body 10. The multiple metal bodies 10 and the connecting body 14 may be formed separately and connected to each other. Furthermore, the connecting body 14 may not be a continuous annular member but may extend intermittently in an annular shape to connect each of two adjacent metal bodies 10. The connecting body 14 may also be provided on multiple protrusions 11.

[0026] 8 and 9 are perspective views of the rotor 2 showing other examples of the metal body 10. As shown in Figs. 8 and 9, the multiple metal bodies 10 may each be embedded inside the multiple protrusions 11. As shown in Figs. 8 and 9, a portion of the metal body 10 may be exposed from the surface of the protrusion 11, or the entire metal body 10 may be embedded inside the protrusion 11. As shown in Fig. 8, the metal body 10 may extend flat, or as shown in Fig. 9, it may extend curved. For example, as shown in Fig. 9, the metal body 10 is curved so as to protrude toward the base 3.

[0027] Next, modified examples of the protrusion 11 will be described. In the above example, the facing portion 11a of the protrusion 11 has a flat or approximately flat surface. However, the facing portion 11a may have a curved surface that protrudes toward the base 3, as shown in FIGS. 10 and 11. Note that FIGS. 10 and 11 show a cross section of the protrusion 11 taken along a plane perpendicular to the radial direction. Also, FIG. 10 shows a metal body 10 corresponding to the metal body 10 in FIGS. 5 to 7, and FIG. 11 shows a metal body 10 corresponding to the metal body 10 in FIG. 9. In the protrusion 11 according to this modified example, as shown in FIGS. 10 and 11, the metal body 10 is curved along the facing portion 11a. Note that the curvature of the curved metal body 10 in a cross section perpendicular to the radial direction may be the same as or different from the curvature of the facing portion 11a of the curved protrusion 11 in a cross section perpendicular to the radial direction. When the curvature of the curved metal body 10 in a cross section perpendicular to the radial direction differs from the curvature of the opposing portion 11a of the curved protrusion 11 in a cross section perpendicular to the radial direction, as shown in FIG. 12 , the ends 10c and 10d of the curved metal body 10 may be embedded inside the opposing portion 11a of the curved protrusion 11. This structure prevents the metal body 10 from falling off the rotor 2. Furthermore, because the ends 10c and 10f of the curved metal body 10 are embedded inside the opposing portion 11a of the curved protrusion 11, i.e., because a portion of the curved metal body 10 is exposed, the air gap with the coil structure can be adjusted more accurately. This improves the detection accuracy of the angle sensor 1.

[0028] FIG. 13 is a perspective view showing another modified example of the rotor 2. The rotor 2 described above may be entirely or partially covered with an insulating member 6. The insulating member 6 is, for example, a resin member. The insulating member 6 is made of, for example, a resin material, a non-magnetic material, a non-conductive material, or the like. The non-magnetic material may be non-conductive. As shown in FIG. 13 , for example, the insulating member 6 has an outer shape that covers the entire rotor 2 in the radial direction, for example, a disk-like outer shape. Furthermore, as shown in FIG. 13 , for example, the insulating member 6 covers the rotor 2 so that the surfaces of the multiple protrusions 11 facing the base 3 are exposed on the surface of the insulating member 6. The insulating member 6 may have other shapes.

[0029] Next, modified examples of the base 3 will be described. In the above example, the conductor 4 is wound around the surfaces of the multiple protrusions 21 and exposed to the outside of the base 3, but the conductor 4 wound around the multiple protrusions 21 may be surrounded or covered by an insulating member 25. For example, as shown in Fig. 14, the insulating member 25 is a cover that covers the conductor 4 wound around the multiple protrusions 21. In this case, the multiple protrusions 11 face the conductor 4 in the radial direction, with the insulating member 25 interposed between them.

[0030] The angle sensor 1 has the above-described configuration, and the shape and number of the protrusions 21 can be freely designed, allowing the shape of the coil structure 30 to be adjusted. This adjustment can improve the accuracy of the angle sensor. Furthermore, the conductor 4 provided on the structural surface 3a of the base 3 forms a planar shape with multiple undulations in the radial direction, forming the coil structure 30 in which multiple coils 31 are connected. In this way, the angle sensor 1 can form various coil structures 30 by winding the conductor 4, thereby increasing the degree of freedom in the arrangement of the multiple coils 31. Therefore, the angle sensor 1 can form a desired coil structure 30 in response to various shapes, and the output waveform obtained from the detection signal detected from the conductor 4 can be made closer to a sine wave, thereby improving the detection accuracy.

[0031] Furthermore, the base 3 of the angle sensor 1 is formed from a material different from that of the substrate 24, and the number of printed circuit boards used in the angle sensor 1 can be reduced.

[0032] Furthermore, by embedding the metal body 10 and the conducting wires 4 in a member such as a resin member, the durability of the metal body 10 and the conducting wires 4 against oil, heat, and dust can be improved.

[0033] Next, an application of the angle sensor 1 will be described. Fig. 15 is an exploded perspective view of a specific example of a rotating device as an application of the angle sensor 1. Fig. 15 shows a rotating device 50 as a specific example of a rotating device in an exploded state. In Fig. 15, a part of the configuration of the rotating device 50 is shown in a see-through manner.

[0034] 15 , a rotating body 52 serving as a rotating device 50 includes an angle sensor 1, a rotating shaft 51, and a rotor 53. The rotating shaft 51 is fixed to the rotor 2 of the angle sensor 1, and the rotor 53 is fixed to the rotating shaft 51. In the rotating device 50, the axes of the rotating shaft 51 and the rotating body 52 coincide or approximately coincide with the axis x of the angle sensor 1. For this reason, in the following description, the axis of the rotating device 50 (rotating body 52) will be referred to as the axis x, and the axes of the angle sensor 1 and the rotating shaft 51 will be referred to as the axis x.

[0035] The rotating body 52 is, for example, a motor, and includes a rotor 53 and a stator 54. A rotating shaft 51 is fixed to the rotor 53. The motor 52 also includes a frame 55. The frame 55 houses the rotor 53 and the stator 54. The frame 55 also has an opening 55a.

[0036] An opening 55a of the frame 55 opens the internal space of the frame 55 to the outside of the frame 55. The rotor 53 and the stator 54 are housed in the internal space of the frame 55. The rotating shaft 51 protrudes from the opening 55a of the frame 55. As shown in Fig. 15, the frame 55 is, for example, a cylindrical member. The frame 55 has an annular end 55b that surrounds the opening 55a, and the end 55b faces in the direction of the axis x.

[0037] The rotor 2 of the angle sensor 1 is fixed to a rotating shaft 51, and one end 51a (hereinafter referred to as the tip) of the rotating shaft 51 penetrates the rotor 2 and also penetrates the opening 23 of the base 3. The tip 51a of the rotating shaft 51 is rotatably supported, for example, by a bearing (not shown). The base 3 of the angle sensor 1 is supported, for example, by a support member (not shown). In the rotating device 50, the rotor 2 is positioned at a predetermined position relative to the base 3 as described above, and the opposing surfaces 11a of the multiple protrusions 11 of the rotor 2 face the protrusions 21 of the base 3 and the multiple coils 31 formed by the planar structure of the conductors 4, with gaps in the axis x direction (see FIGS. 1 and 4 ). The angle sensor 1 may be supported in the rotating device 50 so that the base 3 is closer to the rotating body 52 than the rotor 2. The rotating device 50 may also have a cup-shaped protective cover (not shown), and the angle sensor 1 may be covered by this protective cover. Being covered with a protective cover can provide waterproof and dustproof performance.

[0038] The rotating device 50 has the above-described configuration, and when the rotating body 52 is driven and the rotation shaft 51 rotates, the rotor 2 of the angle sensor 1 fixed to the rotation shaft 51 rotates around the axis x together with the rotation shaft 51. As a result, the metal body 10 of the rotor 2 rotates facing the coils 31 (31a, 31b) formed by the conductors 4 of the base 3 of the angle sensor 1, and the magnetic flux from the excitation circuit 5 acting on each of the multiple coils 31 changes periodically. As a result, a signal that changes with the rotation of the rotor 2 is detected from the conductors 4 forming the multiple coils 31. Based on the detection signal from the conductors 4, an electric circuit device, which is an external device connected to the angle sensor 1, detects the rotation angle of the rotor 2.

[0039] Next, a fixing configuration between the rotating shaft 51 and the rotor 2 of the angle sensor 1 in the rotating device 50 will be described. Fig. 16 is a perspective view showing the tip 51a of the rotating shaft 51 and its vicinity, and Fig. 17 is a perspective view of a specific example of the rotor 2 of the angle sensor 1. As shown in Fig. 16, a recess 51b is formed on the outer circumferential surface of the tip 51a of the rotating shaft 51. Furthermore, as shown in Fig. 17, the rotor 2 is formed with a protrusion 15 that is received in the recess 51b of the rotating shaft 51.

[0040] 16 , a step is formed on the tip end 51a of the rotating shaft 51, and the rotating shaft 51 includes a first outer peripheral surface 51c, a second outer peripheral surface 51d, and a third outer peripheral surface 51e. The first outer peripheral surface 51c is the main outer peripheral surface of the rotating shaft 51 and is a cylindrical surface extending along the axis x from the tip end 51a to the other end of the rotating shaft 51. The second outer peripheral surface 51d and the third outer peripheral surface 51e are formed on the tip end 51a. The second outer peripheral surface 51d is a cylindrical surface extending along the axis x and is adjacent to the first outer peripheral surface 51c. The third outer peripheral surface 51e is a cylindrical surface extending along the axis x and is adjacent to the second outer peripheral surface 51d on the side opposite to the first outer peripheral surface 51c.

[0041] 16, the second outer peripheral surface 51d has a radial width smaller than that of the first outer peripheral surface 51c, and a stepped surface 51f, which is an annular surface, is formed between the first outer peripheral surface 51c and the second outer peripheral surface 51d. The third outer peripheral surface 51e has a radial width smaller than that of the second outer peripheral surface 51d, and a stepped surface 51g, which is an annular surface, is formed between the second outer peripheral surface 51d and the third outer peripheral surface 51e. The stepped surfaces 51f and 51g face in the direction of the axis x.

[0042] As shown in FIG. 16 , the recess 51b is formed in the second outer peripheral surface 51d. The recess 51b is a groove recessed toward the interior of the rotary shaft 51. The recess 51b extends along the axis x. The recess 51b extends to the step surface 51g and opens at the step surface 51g. The recess 51b does not extend to the step surface 51f. That is, the recess 51b extends partway between the step surface 51g and the step surface 51f. The inner peripheral surface 12b of the rotor 2 is fixed to the second outer peripheral surface 51d. For example, a portion of the second outer peripheral surface 51d of the rotary shaft 51 is press-fitted into a space surrounded by the inner peripheral surface 12b of the rotor 2, thereby fixing the inner peripheral surface 12b of the rotor 2 to the second outer peripheral surface 51d. The configuration for fixing the rotor 2 to the outer peripheral surface 51d of the rotating shaft 51 is not limited to the above-described press-fit configuration. For example, the second outer peripheral surface 51d of the rotating shaft 51 may be inserted into the space surrounded by the inner peripheral surface 12b of the rotor 2, and the inner peripheral surface 12b of the rotor 2 and the second outer peripheral surface 51d may be bonded together with an adhesive or the like to fix the inner peripheral surface 12b of the rotor 2 to the second outer peripheral surface 51d. Alternatively, a separate member such as a metal ring (not shown) may be press-fitted to sandwich the rotor 2 between the stepped surface 51f of the rotating shaft 51 and the ring. If the ring is made of metal, it may be made of the same material as the rotating shaft 51. In this case, the linear expansion coefficient of the ring is the same as that of the rotating shaft 51, thereby preventing the rotor 2 from coming loose due to thermal deformation. Furthermore, the ring may be made of a material different from that of the rotating shaft 51.

[0043] As described above, the recess 51b does not extend to the step surface 51f, which shortens the cutting time. In addition, the cutting area can be reduced, which prevents the strength of the rotating shaft 51 from decreasing.

[0044] 16, the first outer peripheral surface 51c and the third outer peripheral surface 51e at the position of the recess 51b in the circumferential direction are curved surfaces. The second outer peripheral surface 51d is, for example, a cylindrical or approximately cylindrical surface extending along the axis x, and the third outer peripheral surface 51e is, for example, a cylindrical or approximately cylindrical surface extending along the axis x.

[0045] As shown in Fig. 17 , the protrusion 15 is formed on the inner circumferential surface 12b of the rotor 2. The protrusion 15 is a portion that protrudes inward from the inner circumferential surface 12b, and extends in the direction of the axis x, for example, as shown in Fig. 17 , from the end face 16 to partway between the end faces 16 and 17. Note that the protrusion 15 may also extend to the end face 17. Note that the end faces 16 and 17 are surfaces that face the direction of the axis x of the ring 12, and the end faces 16 and 17 are back-to-back.

[0046] As described above, when the rotor 2 is molded from a resin material, it is easy to mold the protrusion 15 so that it extends partway between the end face 16 and the end face 17, that is, to be small in the direction of the axis x. This allows the length of the recess 51b that houses the protrusion 15 in the direction of the axis x to be small. Note that the entire rotor 2 does not have to be molded from a resin material. For example, the ring 12 may be made of resin and the rest may not be made of resin, or the ring 12 may be made of a material other than resin and the rest may be made of resin.

[0047] By inserting the tip end 51a of the rotating shaft 51 into the rotor 2 so that the protrusion 15 of the rotor 2 fits into the recess 51b of the rotating shaft 51, the circumferential position of the rotor 2 relative to the rotating shaft 51 is set to a predetermined position. In this way, in this specific example, the circumferential positioning of the rotor 2 relative to the rotating shaft 51 is facilitated when fixing the rotor 2 to the rotating shaft 51. When the rotor 2 is fixed to the rotating shaft 51, the end face 17 of the rotor 2 is in contact with the stepped surface 51f of the rotating shaft 51. When the rotor 2 is fixed to the rotating shaft 51, the end face 17 of the rotor 2 does not have to be in contact with the stepped surface 51f of the rotating shaft 51.

[0048] It goes without saying that the rotating body of the rotating device according to the present invention includes a rotating object such as a motor, but also includes rotating bodies other than motors. For example, the rotating body of the rotating device according to the present invention includes rotating bodies such as power steering, accelerator pedals, brake pedals, seat reclining mechanisms, and electric parking mechanisms of automobiles.

[0049] Although the shape of the base 3 is rectangular in this embodiment, it is not limited to a rectangle. For example, the shape of the base 3 may be circular or a circle with rectangles connected together when viewed from the front. In this case, the shape of the base 3 can be freely changed to match the area for the conductors 4 and the area for the substrate 24, which allows for a reduction in the amount of material used and a reduction in the weight of the angle sensor 1.

[0050] Furthermore, the base 3 may be provided with a through hole for mounting to a rotating device or the like.

[0051] 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.

[0052] 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.

[0053] 1 Angle sensor, 2 Rotor, 3 Base, 3a Structural surface, 4 Conductor, 5 Excitation circuit, 6 Insulating member, 10 Metal body, 10a, 10b End face, 10c, 10d End, 10e Intermediate portion, 11 Convex, 11a Opposing surface, 12 Ring, 12a Outer circumferential surface, 12b Inner circumferential surface, 13 Opening, 14 Connector, 15 Convex portion, 16, 17 End face, 21 Protrusion, 22 Protrusion, 23 Opening, 24 Board, 24a Electronic component, 24b Wiring, 24c Terminal, 25 Insulating member, 30, 30a, 30b Coil structure, 31, 31a, 31b Coil, 50 Rotating device, 51 Rotating shaft, 51a Tip portion, 51b Recess, 51c First outer circumferential surface, 51d Second outer circumferential surface, 51e Third outer peripheral surface, 51f, 51g stepped surface, 52 motor, 53 rotor, 54 stator, 55 frame, 55a opening, W, W0 width, x axis

Claims

1. An angle sensor comprising: a rotor having a plurality of protrusions extending radially; a base; and a covered conductor, wherein the conductor provided on a surface of the base forms a planar shape having a plurality of undulations in the radial direction, and the protrusions face the conductor in the direction of the rotation axis.

2. The angle sensor according to claim 1, wherein a surface of the base is provided with a plurality of protrusions extending from the base toward the rotor, and the conducting wire is wound around the plurality of protrusions.

3. The angle sensor according to claim 1 or 2, wherein the protrusion faces the protruding portion in the rotation axis direction.

4. The angle sensor according to claim 1, wherein an opening is provided between two of the plurality of protrusions.

5. An angle sensor according to any one of claims 1 to 4, wherein the rotor comprises a ring and the plurality of protrusions connected to an outer periphery of the ring.

6. An angle sensor according to any one of claims 1 to 5, comprising a substrate having electronic components, wiring, and terminals electrically connected to the conductors.

7. The angle sensor according to claim 1, wherein the rotor has a plurality of metal bodies, and the plurality of metal bodies are located inside the protrusion.

8. An angle sensor according to any one of claims 1 to 6, wherein the rotor has a plurality of metal bodies, the protrusion has a surface facing the conductor, and the plurality of metal bodies are on the surface.

9. The angle sensor according to claim 7 or 8, wherein the metal body has an end portion, another end portion, and an intermediate portion between the end portion and the other end portion, and the width of the end portion of the metal body and the width of the other end portion of the metal body are smaller than the width of the intermediate portion of the metal body in the circumferential direction.

10. An angle sensor according to any one of claims 7 to 9, wherein the rotor is provided with connectors that electrically connect the plurality of metal bodies to each other.

11. The angle sensor according to any one of claims 1 to 10, wherein the conductor is covered with an insulating member, and the protrusion faces the conductor via the insulating member.

12. The angle sensor according to claim 1, wherein the metal body is curved so as to protrude toward the side of the base.

13. A rotating device comprising: an angle sensor according to any one of claims 1 to 12; a rotating shaft fixed to a rotor of the angle sensor; and a rotating body fixed to the rotating shaft.

14. The rotating device according to claim 13, wherein a recess is formed on an outer circumferential surface of the rotating shaft, and a rotor of the angle sensor is fixed to the outer circumferential surface of the rotating shaft.

15. The rotating device according to claim 14, wherein the rotating shaft has a first outer peripheral surface, a second outer peripheral surface that is narrower than the width of the first outer peripheral surface in the radial direction, and a third outer peripheral surface that is narrower than the width of the second outer peripheral surface in the radial direction, and the recess is formed in the second outer peripheral surface.

16. The rotating device according to claim 15, wherein the first outer peripheral surface and the third outer peripheral surface at the position of the recess in the circumferential direction are curved surfaces.

17. The rotating device according to claim 14, wherein a rotor of the angle sensor is formed with a protrusion that is received in a recess of the rotating shaft.

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