angle sensor

Abstract

The angle sensor (1) comprises: a plurality of walls (11) extending along an axis (x); a plurality of spokes (12) connected to the plurality of walls (11); and a plurality of coils (20) wound around the plurality of spokes (12). In the radial direction, the plurality of coils (20) are opposite to the plurality of walls (11). In the circumferential direction, the width (w11) of the wall (11) is the same as or greater than the width (w21) of the spokes (12).

Description

Technical Field

[0001] This invention relates to an angle sensor, and more particularly to an inductive angle sensor. Background Technology

[0002] Conventionally, various sensors have been used to detect the rotation angle of motors, etc. Among such angle sensors for detecting rotation angles are inductive sensors (for example, see Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-200106 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] There is room for improvement in the detection accuracy of traditional inductive sensors.

[0008] Therefore, the purpose of this invention is to provide an angle sensor that can improve detection accuracy.

[0009] Solution for solving the problem

[0010] An angle sensor according to one embodiment of the present invention comprises: a plurality of walls extending along a rotation axis; a plurality of spokes connected to the plurality of walls; and a plurality of coils wound around the plurality of spokes, wherein the plurality of coils are radially opposed to the plurality of walls, and in the circumferential direction, the width of the walls is the same as or greater than the width of the spokes. Attached Figure Description

[0011] Figure 1 This is a schematic diagram showing the structure of an angle sensor according to one embodiment of the present invention. It is a partial perspective perspective view showing the internal structure schematically through a portion of the components of the angle sensor.

[0012] Figure 2 It is a three-dimensional diagram that roughly represents the structure of the angle sensor.

[0013] Figure 3 This is a front view that roughly represents the structure of the angle sensor.

[0014] Figure 4 This is a side view that roughly represents the structure of the angle sensor.

[0015] Figure 5 It means Figure 3 A magnified view of the portion enclosed by frame A.

[0016] Figure 6 It is a three-dimensional diagram that roughly represents the structure of the stator.

[0017] Figure 7 It is a front view that roughly represents the structure of the stator.

[0018] Figure 8 This is a three-dimensional diagram showing an example of a coil structure formed by multiple coils.

[0019] Figure 9 It is a schematic representation Figure 8 The diagram shows the structure of the coil.

[0020] Figure 10 It is a diagram that magnifies the wall and spokes.

[0021] Figure 11 It is a diagram that magnifies the wall and spokes.

[0022] Figure 12 It is a diagram that magnifies the wall and spokes.

[0023] Figure 13 It is a diagram that magnifies the wall and spokes.

[0024] Figure 14 It is a diagram that magnifies the wall and spokes.

[0025] Figure 15 It is a diagram showing electromagnetic wires forming multiple coils wound around multiple spokes.

[0026] Figure 16 This is a three-dimensional diagram showing a modified example of the stator. Detailed Implementation

[0027] Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings. It should be noted that, in the drawings, for multiple components, sometimes not all components are labeled, and some of the labels for multiple components are omitted. Figure 1 This is a schematic diagram showing the structure of an angle sensor 1 according to one embodiment of the present invention. It is a partial perspective perspective view showing the internal structure schematically through a portion of the components of the angle sensor 1. Figure 2 This is a three-dimensional diagram that roughly represents the structure of angle sensor 1. Figure 3 This is a front view that roughly represents the structure of angle sensor 1. Figure 4 This is a side view that schematically represents the structure of angle sensor 1. Furthermore, Figure 5 It means Figure 3 A magnified view of the portion enclosed by frame A. (See attached image.) Figures 1-5As shown, the angle sensor 1 includes: a plurality of walls 11 extending along the x-axis; a plurality of spokes 12 connected to the plurality of walls 11; and a plurality of coils 20 wound around the plurality of spokes 12. In the radial direction, the plurality of coils 20 are opposite to the plurality of walls 11. In the circumferential direction, the width w11 of the wall 11 is the same as or greater than the width w21 of the spokes 12. The structure of the angle sensor 1 will be described in detail below. It should be noted that the x-axis is the rotation axis of the angle sensor 1. Furthermore, radial direction refers to the direction orthogonal to the x-axis.

[0028] like Figures 1-4 As shown, specifically, the angle sensor 1 includes a rotor 2 and a stator 3. The rotor 2 has a cylinder 30 and a conductor structure 4 fixed to the cylinder 30. Multiple walls 11 and multiple spokes 12 are provided on the stator 3, and multiple coils 20 are mounted on the stator 3 such that they cover the cylinder 30 from the radially outer side (hereinafter also referred to as the "outer peripheral side"). The rotor 2 and the stator 3 are radially opposed to each other on the cylinder 30. It should be noted that... Figures 2-4 In the diagram, rotor 2 and stator 3 are shown in a prescribed positional relationship. This prescribed positional relationship is an example of the positional relationship between rotor 2 and stator 3 when angle sensor 1 is mounted on the application object in its operating state. In angle sensor 1, rotor 2 is disposed inside stator 3.

[0029] like Figures 1-4 As shown, the cylinder 30 of rotor 2 is a cylindrical component extending along the axis x. It should be noted that... Figure 1 In the image, the interior of the cylinder 30 is shown through a perspective view. The cylinder 30 of the rotor 2 is mounted on a rotating component of an external device that is the object of the angle sensor 1, and its axis x is aligned with or approximately aligned with the rotation axis of the rotating component of the external device. For example, as... Figures 1-4 As shown, the rotor 2's cylinder 30 has: an inner circumferential surface 31, which is a cylindrical surface extending along a cylindrical surface centered on the axis x; and an outer circumferential surface 32, which is a cylindrical surface on the outer circumferential side opposite to the inner circumferential surface 31. Furthermore, the cylinder 30 has end faces 33 and 34 facing various directions extending along the axis x. The inner circumferential surface 31 and the outer circumferential surface 32 extend between end faces 33 and 34. The angle sensor 1 is used, for example, in a motor, where the motor shaft passes through the inner circumferential surface 31 of the rotor 2's cylinder 30, and the rotor 2 is fixed to the shaft. The cylinder 30 is made of, for example, resin, a non-magnetic material, or a non-conductive material. It should be noted that a non-magnetic material can also be non-conductive.

[0030] Conductor structure 4 is formed by conductors, for example Figure 1 As shown, it consists of multiple conductors 5. These conductors 5 are arranged, for example, circumferentially about the axis x, as follows: Figure 1As schematically shown, multiple conductors 5 form a cylindrical conductor structure 4 extending in a ring around an axis x. The conductors 5 can be any conductive material (a material capable of generating so-called eddy currents or induced currents (currents) in one plane), such as a metallic body. The multiple conductors 5 are arranged at a predetermined distance apart in the circumferential direction of the cylinder 30. That is, two adjacent conductors 5 are separated by a predetermined distance around the axis x. The multiple conductors 5 are arranged, for example, at equal or approximately equal angular intervals in the circumferential direction along a cylindrical surface centered on the axis x. The multiple conductors 5 may have a curved shape, for example. The multiple conductors 5 can also be connected to each other. The multiple conductors 5 are connected by one or more connecting parts, which can be formed of non-conductive materials (e.g., resin) or conductive materials (e.g., metal), and the multiple conductors 5 can also be electrically connected.

[0031] For example Figure 1 As shown, multiple conductors 5 are disposed within the cylinder 30. Alternatively, the conductors 5 may be entirely embedded within the cylinder 30; or, a portion of each conductor 5 may protrude from the surface of the cylinder 30. Furthermore, the multiple conductors 5 may also be mounted on the surface of the cylinder 30, such as the outer peripheral surface 32. In this case, a portion of the conductors 5 may also be embedded within the cylinder 30.

[0032] Figure 6 It is a three-dimensional diagram that roughly represents the structure of stator 3. Figure 7 This is a front view that roughly represents the structure of stator 3. For example... Figures 1-4 , Figure 6 , Figure 7 As shown, the stator 3 has a cylindrical portion, namely a cylindrical section 41, corresponding to the cylinder 30 of the rotor 2. The cylindrical section 41 has an internal space capable of accommodating the rotor 2 and has an inner circumferential surface 42 defining this space. The inner circumferential surface 42 is a cylindrical surface extending along the axis x, and is opposed to the outer circumferential surface 32 of the cylinder 30 of the rotor 2 across an annular gap. The inner circumferential surface 42 is, for example, a cylindrical surface extending along a cylindrical surface with the axis x as its central axis.

[0033] In addition, such as Figures 1-4 , Figure 6 , Figure 7 As shown, the stator 3 has a portion, namely the mounting portion 44, that is, assembled to an external device that is the object of application. For example... Figures 1-4 , Figure 6 , Figure 7 As shown, the mounting portion 44 is provided, for example, on the outer peripheral surface 43 of the cylindrical portion 41, protruding outward from the cylindrical portion 41. The outer peripheral surface 43 of the cylindrical portion 41 is a cylindrical surface opposite to the inner peripheral surface 42. Furthermore, the mounting portion 44, for example, has a through hole 44a through which a fixing member such as a bolt passes, and the mounting portion 44 can be mounted to an external device by means of a fixing member. The stator 3, for example, has three mounting portions 44. It should be noted that the number of mounting portions 44 in the stator 3 is not limited to this. Furthermore, as... Figures 1-4 , Figure 6 , Figure 7 As shown, the stator 3, for example, has a holding section 45 that houses a circuit device (not shown) having a circuit section and an arithmetic section. For example... Figures 1-4 , Figure 6 , Figure 7 As shown, the retaining portion 45 extends from the outer peripheral surface 43 of the cylindrical portion 41 along the axis x to one side in the direction of the axis x. In addition, the retaining portion 45 is provided circumferentially between a plurality of assembly portions 44.

[0034] As described above, the stator 3 has multiple walls 11 and multiple spokes 12. Figures 5-7 As shown, multiple walls 11 and multiple spokes 12 are connected to form multiple protrusions 10 protruding toward the rotor 2. Figure 5 As shown, a plurality of protrusions 10 protrude radially inward from the inner circumferential surface 42 of the cylindrical portion 41 (hereinafter also referred to as "inner circumferential side"). The protrusions 10 are provided on the inner circumferential surface 42 at equal or approximately equal angles around the axis x. That is, a plurality of spokes 12 protrude radially from the inner circumferential surface 42 of the cylindrical portion 41, and the plurality of spokes 12 are provided on the inner circumferential surface 42 at equal or approximately equal angles around the axis x. Figure 5 As shown, multiple walls 11 are connected to the front ends 12a of multiple spokes 12. It should be noted that the front ends 12a of the spokes 12 are the inner circumferential ends of the spokes 12. The multiple walls 11 are arranged, for example, at equal or approximately equal angular intervals around the axis x. In this way, the multiple walls 11 are radially opposed to the inner circumferential surface 42 of the cylinder portion 41, separated by multiple spokes 12. The specific configurations of the multiple walls 11 and the multiple spokes 12 will be described later.

[0035] The stator 3 is integrally formed from the same material, and the various structures of the stator 3 are integrally connected. The stator 3 is an insulating component, for example, a resin component. The stator 3 is made of, for example, resin material, non-magnetic material, non-conductive material, etc. It should be noted that non-magnetic materials can also be non-conductive. It should be noted that any one or all of the structures of the stator 3 can also be formed separately. In this case, the separately formed structures are assembled by means of bonding or the like to form the stator 3.

[0036] Coil 20 is made of a conductive component 21. Multiple coils 20 are connected, for example, in a circumferential arrangement around an axis x. Figure 1As schematically shown, a plurality of coils 20 form a cylindrical shape (hereinafter referred to as "coil configuration") 6 extending in a ring around an axis x. The coil configuration 6 is a shape formed by arranging a plurality of coils 20. In the coil configuration 6, the plurality of coils 20 are arranged in a ring, for example, along a surface forming a ring around the axis x. The plurality of coils 20 are arranged in a ring, for example, along a cylindrical surface with the axis x as its central axis. Furthermore, each coil 20 has, for example, a shape that encloses a space. Furthermore, each coil 20 has, for example, a shape where the space enclosed by each coil 20 is a ring-shaped surface along the axis x.

[0037] Figure 8 This is a perspective view showing an example of a coil structure 6 formed by multiple coils 20. Furthermore, Figure 9 It is a schematic representation Figure 8 The diagram shows the structure of coil configuration 6. Coil 20 is, for example, a coil formed by winding electromagnetic wire 21, which serves as a conductive component 21. Figure 1 , Figure 8 , Figure 9 As shown, the coil 20 is formed by winding an electromagnetic wire 21 around a plurality of protrusions 10. The coil 20 has a ring shape wound radially r around a cylinder 30, enclosing a radially facing planar space. A plurality of coils 20 are formed in the cylinder portion 41 of the stator 3 in an arrangement around an axis x, forming a coil structure 6. It should be noted that the conductive component 21 forming the coil 20 is not limited to an electromagnetic wire.

[0038] like Figure 8 , Figure 9 As shown, the coil structure 6 has two pieces (hereinafter referred to as coil structure pieces) 6a and 6b. Coil structure piece 6a is formed by connecting multiple coils 20, i.e., coil 20a, in a ring-like manner. Similarly, coil structure piece 6b is formed by connecting multiple coils 20, i.e., coil 20b, in a ring-like manner. That is, in each of coil structure pieces 6a and 6b, multiple ring-shaped coils 20a and 20b are arranged circumferentially. It should be noted that coil structure pieces 6a and 6b are, for example, covered by an insulating material (insulating film or coating) and are electrically insulated from each other. Figure 8 , Figure 9As shown, coil construction pieces 6a and 6b overlap radially to form coil construction 6. In coil construction pieces 6a and 6b, a portion of the space enclosed by coil 20a is offset circumferentially from a portion of the space enclosed by coil 20b, and another portion of the space enclosed by coil 20a overlaps circumferentially with another portion of the space enclosed by coil 20b. Specifically, the space enclosed by coil 20a is located at a position offset circumferentially from the space enclosed by coil 20b by half the width of the space enclosed by coil 20a. It should be noted that the number of coils 20a and 20b in each of coil construction pieces 6a and 6b corresponds to the axial multiple angle set by angle sensor 1. Furthermore, the number of coil construction pieces 6a and 6b corresponds to the number of detection signals output by coil construction 6.

[0039] like Figure 5 , Figure 9 As shown, an electromagnetic wire 21, serving as a conductive component, is wound radially around each protrusion 10, forming multiple loop-shaped coils 20 along the radial direction r of the multiple protrusions 10, thus forming a coil structure 6 on the stator 3. It should be noted that, as described later, the electromagnetic wire 21 is wound around the spokes 12 of the protrusions 10. For example, coil structure pieces 6a and 6b are formed by winding an electromagnetic wire 21a or 21b around multiple protrusions 10 of the cylindrical portion 41. Specifically, for example, on one circumferential side, the electromagnetic wire 21a or 21b is wound alternately around each two adjacent protrusions 10 from one side and the other side of the x-axis, folded back after one revolution around the cylindrical portion 41, and then wound around the protrusions 10 in the same manner on the other circumferential side, forming coil structure pieces 6a and 6b. In this case, each coil 20a or 20b is formed around two protrusions 10. Furthermore, coil construction pieces 6a and 6b are offset by a protrusion 10 in the circumferential direction. It should be noted that each coil 20a, 20b is not limited to being formed around two protrusions 10; it can also be formed around other numbers of protrusions 10. Furthermore, while the case of winding the electromagnetic wire 21 (21a, 21b) once has been described, the winding method of the electromagnetic wire 21 is not limited to this; it can also be wound more than twice. In other words, the coil formed by winding the electromagnetic wire 21 can have, for example, one layer in the radial direction, or multiple layers such as two, three, four, or five layers. If the number of turns or layers is high, the output signal or the detected signal (e.g., the amplitude of the signal waveform) can be amplified.

[0040] like Figure 5 , Figure 9As shown, the coils 20 (20a, 20b) formed by the plurality of protrusions 10 wound around the cylindrical portion 41 extend in a straight line. That is, portions of each coil 20 extending along each protrusion 10 on one side and the other side of the x-axis extend in a straight line. Furthermore, portions (electromagnetic wires 21a, 21b) of coil construction pieces 6a, 6b extending between two adjacent protrusions 10 on one side and the other side of the x-axis intersect. Specifically, electromagnetic wires 21a, 21b intersect between two adjacent protrusions 10. The two adjacent coils 20 (20a, 20b) are connected by these portions (electromagnetic wires 21a, 21b) of coil construction pieces 6a, 6b intersecting.

[0041] It should be noted that the two ends of the electromagnetic wire 21, which is wound around the protrusion 10 to form multiple coils 20, are led out from the cylindrical portion 41. For example Figure 9 As shown, the two ends 21a1, 21a2 of the electromagnetic wire 21a and the two ends 21b1, 21b2 of the electromagnetic wire 21b are led out from between two adjacent protrusions 10. Figure 9 As shown, as an example, the ends 21a1, 21a2 of electromagnetic wire 21a and the ends 21b1, 21b2 of electromagnetic wire 21b are led out through the gap between the first protrusion 10 and the second protrusion 10.

[0042] The rotor 2 and stator 3 form an inductive angle sensor, and multiple coils 20 form detection coils. Furthermore, a magnetic space or gap is formed between the rotor 2 and the stator 3. For example, in the angle sensor 1, a radially oriented magnetic flux of periodically varying magnitude acts on the multiple coils 20. Specifically, for example, an excitation circuit 7 (see reference 1) is provided in the stator 3. Figure 4 The excitation circuit 7 is a magnetic circuit that generates periodically changing magnetic flux acting on the plurality of coils 20. On the other hand, as described above, the plurality of conductors 5 are arranged circumferentially about the axis x, and cut across the magnetic flux generated by the excitation circuit 7 as the rotor 2 rotates. Furthermore, the radial projection of the conductors 5, which have portions extending along the axis x, onto the coils 20 moves as the rotor 2 rotates. Therefore, the magnetic flux from the excitation circuit 7 acting on the plurality of coils 20 is canceled out by the eddy currents generated by the conductors 5, thereby causing the magnetic flux to change periodically as the rotor 2 rotates. Thus, through electromagnetic induction, an electromotive force that changes with the rotation of the rotor 2 is generated in the plurality of coils 20, and the signal changing with the rotation of the rotor 2 is 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 circuit device.

[0043] Next, the shapes of the wall 11 and the spokes 12 will be described in detail. Figures 10-14This is a diagram showing the wall 11 and the spokes 12 in an enlarged form. Figure 10 This is a diagram showing the wall 11 and spokes 12 from a radial perspective. Figure 11 , Figure 13 This is a diagram showing the wall 11 and spokes 12 viewed from one side along the x-axis. Figure 12 , Figure 14 This is a diagram showing the wall 11 and spokes 12 viewed from the other side of the x-axis.

[0044] As mentioned above, such as Figure 5 , Figures 10-14 As shown, a protrusion 10 is formed by a wall 11 and spokes 12. The wall 11 is connected to the front end 12a of the spokes 12, which protrudes from the inner circumferential surface 42 of the cylinder portion 41 of the stator 3. The circumferential width w11 of the wall 11 is the same as (w11 = w21) or greater than the circumferential width w21 of the spokes 12 (w11 > w21). Furthermore, the width of the wall 11 in the x-axis direction (hereinafter referred to as width w12) is greater than the width of the spokes 12 in the x-axis direction (hereinafter referred to as width w22) (w12 > w22).

[0045] like Figures 10-14 As shown, the spokes 12 have mutually opposing ends 13a and 13b in the circumferential direction, and mutually opposing ends 13c and 13d in the axial x-direction. Ends 13a and 13b are faces facing the circumferential direction. Furthermore, ends 13c and 13d are faces facing directions extending along the axial x-direction. Ends 13a and 13b extend, for example, along the axial x-direction and have a constant or substantially constant width in the radial direction. Specifically, for example, ends 13a and 13b extend parallel or substantially parallel to the axial x-direction. Furthermore, ends 13c and 13d extend, for example, in the circumferential direction and have a constant or substantially constant width in the radial direction. Specifically, for example, ends 13c and 13d extend in the circumferential direction in a manner parallel or substantially parallel to a plane orthogonal to the coaxial x-direction. In this way, the spokes 12 protrude radially from the inner circumferential surface 42 of the cylinder portion 41 of the stator 3, and for example, the radially orthogonal cross-section of the spokes 12 is rectangular or substantially rectangular. It should be noted that the cross-sectional shape of the spoke 12 is not limited to a rectangle, but can also be other shapes.

[0046] As described above, the multiple spokes 12 are arranged at equal or approximately equal angular intervals around the axis x, such as Figures 11-13 As shown, in the circumferential direction, a gap 46 is formed between two adjacent spokes 12. The circumferential width of this gap 46 between two adjacent spokes 12 is width g1. The width g1 of the gap 46 between two spokes 12 is smaller than the circumferential width w21 of the spokes 12 (see reference). Figure 5(g1 < w21). It should be noted that the gap 46 is the circumferential gap between the end 13a of one of the two adjacent spokes 12 and the end 13b of the other spoke 12. In addition, the width g1 is the circumferential distance between the end 13a of one of the two adjacent spokes 12 and the end 13b of the other spoke 12.

[0047] like Figures 10-14 As shown, wall 11 has ends 14a and 14b that are opposite to each other in the circumferential direction, and ends 14c and 14d that are opposite to each other in the axial x direction. Ends 14a and 14b extend, for example, along the axial x and have a constant or substantially constant width in the radial direction. Specifically, for example, ends 14a and 14b extend parallel to or substantially parallel to the axial x. Furthermore, ends 14c and 14d extend, for example, in the circumferential direction and have a constant or substantially constant width in the radial direction. Specifically, for example, ends 14c and 14d extend in the circumferential direction in a manner parallel to or substantially parallel to a plane orthogonal to the coaxial x. In this way, the shape of wall 11 when viewed radially is rectangular or substantially rectangular. It should be noted that the shape of wall 11 when viewed radially is not limited to a rectangle and may be other shapes. In addition, wall 11 has a surface 15a facing the inner circumferential side, which is opposite to the outer circumferential surface 32 of the cylinder 30 of rotor 2 across an annular gap. Each of the multiple walls 11 has a face 15a that extends, for example, along a cylindrical surface centered on axis x.

[0048] As described above, a plurality of walls 11 are arranged at equal or approximately equal angular intervals around axis x. In the circumferential direction, a gap 47 is formed between two adjacent walls 11. The circumferential width of this gap 47 between two adjacent walls 11 is width g2. Gap 47 communicates with gap 46. It should be noted that gap 47 is the circumferential gap between the end 14a of one wall 11 and the end 14b of the other wall 11. Furthermore, width g2 is the circumferential distance between the end 14a of one wall 11 and the end 14b of the other wall 11.

[0049] like Figures 10-12As shown, in each protrusion 10, the radially extending ends 14a and 14b of the wall 11 and the radially extending ends 13a and 13b of the spokes 12 extend continuously in the radial direction. That is, in each protrusion 10, the radially extending ends 14a and 14b of the wall 11 and the radially extending ends 13a and 13b of the spokes 12 are flush with each other. For example, in each protrusion 10, the end 14a of the wall 11 and the end 13a of the spokes 12 form a plane or a substantially plane, and similarly, the end 14b of the wall 11 and the end 13b of the spokes 12 form a plane or a substantially plane. The surface formed by the end 14a of the wall 11 and the end 13a of the spokes 12 extends, for example, in a plane extending radially including the axis x. Similarly, the surface formed by the end 14b of the wall 11 and the end 13b of the spokes 12 extends, for example, in a plane extending radially including the axis x. In this case, the width g2 of gap 47 increases as it tends to the radially outward side, and the width g1 of gap 46 also increases as it tends to the radially outward side.

[0050] Furthermore, the surface formed by the end 14a of the wall 11 and the end 13a of the spoke 12 of one of the two circumferentially adjacent protrusions 10 may also be parallel or substantially parallel to each other with the surface formed by the end 14b of the wall 11 and the end 13b of the spoke 12 of the other protrusion 10. Specifically, for example, the surface formed by the end 14a of the wall 11 and the end 13a of the spoke 12 of one of the two circumferentially adjacent protrusions 10 may also be parallel or substantially parallel to the plane containing the axis x passing through the middle of these surfaces in the circumferential direction with the surface formed by the end 14b of the wall 11 and the end 13b of the spoke 12 of the other protrusion 10. In this case, the width g2 of the gap 47 is constant or substantially constant in the radial direction, the width g1 of the gap 46 is constant or substantially constant in the radial direction, and the width g2 of the gap 47 is the same as or substantially the same as the width g1 of the gap 46.

[0051] It should be noted that, in each protrusion 10, the shape of the radially continuous surface formed by the end 14a of the wall 11 and the end 13a of the spoke 12 is not limited to the shape described above. Similarly, in each protrusion 10, the shape of the radially continuous surface formed by the end 14b of the wall 11 and the end 13b of the spoke 12 is not limited to the shape described above.

[0052] The width g1 of the gap 46 between two adjacent spokes 12 in the circumferential direction is large enough to accommodate an electromagnetic wire 21 wound multiple times on the spokes 12 to form multiple coils 20. In this way, the gap 46 allows the electromagnetic wire 21 to be wound on the spokes 12 without winding it over the spokes 12 onto the wall 11. In this embodiment, the width g1 of the gap 46 is large enough to accommodate one intersection connecting the coils 20, and is also wide enough for the electromagnetic wire 21 to be wound around once. It should be noted that a portion of the electromagnetic wire 21 can also be wound around the wall 11 as long as it does not detach from the protrusion 10. Furthermore, as described above, the winding method of the electromagnetic wire 21 is not limited to one turn; when the electromagnetic wire 21 is wound around twice or more, the gap 46 can also be wide enough to allow the electromagnetic wire 21 to be wound around twice or more.

[0053] It should be noted that, as described above, the two ends 21a1, 21a2 of the electromagnetic wire 21a and the two ends 21b1, 21b2 of the electromagnetic wire 21b are led out from between two adjacent protrusions 10. For example, as shown... Figure 9 As shown, the wires are led out through the gap between the first protrusion 10 and the second protrusion 10. Therefore, for example, the ends 21a1, 21a2 of the electromagnetic wire 21a and the ends 21b1, 21b2 of the electromagnetic wire 21b are accommodated in a gap 47 of the cylindrical portion 41 that is connected to the gap 46. Furthermore, if there is space in the gap 46, the ends 21a1, 21a2 of the electromagnetic wire 21a and the ends 21b1, 21b2 of the electromagnetic wire 21b can also be accommodated in the gap 46.

[0054] like Figure 10 , Figure 13 As shown, in each protrusion 10, the end 14c of the wall 11 on the x-axis side protrudes further along the x-axis side than the end 13c of the spoke 12 on the x-axis side. Furthermore, as... Figure 10 , Figure 14 As shown, in each protrusion 10, the end 14d on the other side of the axis x of the wall 11 protrudes further on the other side of the axis x of the spoke 12 than the end 13d on the other side of the axis x of the spoke 12. Therefore, in each protrusion 10, as... Figure 13 As shown, a surface 15b, extending between end 14c and end 13c and opposite to surface 15a, is formed on wall 11. Furthermore, as... Figure 14 As shown, a surface 15c, which extends between end 14d and end 13d and is opposite to surface 15a, is formed on wall 11. Thus, in each protrusion 10, a step is formed between the end 13c, 13d of the spoke 12 and the end 14c, 14d of the wall 11, respectively. Surface 15b is the inner circumferential wall relative to the end 13c of the spoke 12, and surface 15c is the inner circumferential wall relative to the end 13d of the spoke 12.

[0055] like Figure 10 , Figure 13 , Figure 14 As shown, the ends 13c and 13d of the plurality of spokes 12 are respectively located on the inner side (opposite ends 13d and 13c sides) of the protrusion 10 in the x-axis direction relative to the sides 41a and 41b of the cylindrical portion 41, forming recesses 16a and 16b that are recessed relative to the sides 41a and 41b of the cylindrical portion 41 in the x-axis direction toward the inner side of the protrusion 10. It should be noted that the sides 41a and 41b of the cylindrical portion 41 are annular surfaces facing one side and the other side of the cylindrical portion 41 in the x-axis direction, respectively, and are surfaces extending between the inner circumferential surface 42 and the outer circumferential surface 43.

[0056] It should be noted that the ends 13c and 13d of the plurality of spokes 12 may not each form a recess 16a and 16b. For example, the ends 13c and 13d of the plurality of spokes 12 may each be flush with the sides 41a and 41b of the cylinder 41, and may also be configured to protrude toward the ends 14c and 14d in the x-axis direction than the sides 41a and 41b of the cylinder 41.

[0057] As described above, multiple coils 20 are wound around multiple spokes 12. Specifically, the multiple coils 20 are wound around the multiple spokes 12 along the ends 13a, 13b, 13c, and 13d of the multiple spokes 12. Figure 15 As shown, electromagnetic wires 21 forming multiple coils 20 extend along the ends 13c, 13d of the spokes 12 and the surfaces 15b, 15c of the wall 11. In this way, the electromagnetic wires 21 forming multiple coils 20 are opposed to the surfaces 15b, 15c of the wall 11, and the multiple coils 20 are radially opposed to the wall 11. Furthermore, the electromagnetic wires 21 forming multiple coils 20 extend within the gap 46 between two adjacent spokes 12 in the circumferential direction.

[0058] Within the gap 46, electromagnetic wires 21 forming multiple coils 20 intersect. That is, the electromagnetic wires 21 extend between the end 13c of one spoke 12 and the end 13d of the other adjacent spoke 12 in the circumferential direction, and also between the end 13d of one spoke 12 and the end 13c of the other adjacent spoke 12 in the circumferential direction. In this way, the electromagnetic wires 21 forming multiple coils 20 are inclined within the gap 46 relative to a direction parallel to the axis x. Furthermore, the electromagnetic wires 21 forming multiple coils 20 intersect within the gap 46.

[0059] The less deviation the output signals of each of the multiple coils 20, the higher the detection accuracy of the angle sensor 1 and the higher the detection accuracy of the rotation angle of the rotor 2. Therefore, the less deviation the area enclosed by each of the multiple coils 20, the higher the detection accuracy of the angle sensor 1. As described above, the electromagnetic wires 21 forming the multiple coils 20 extend obliquely within the gap 46 relative to the direction parallel to the axis x. When the obliqueness of the electromagnetic wires 21 within the multiple gaps 46 relative to the direction parallel to the axis x is different, the area enclosed by each of the multiple coils 20 will deviate. Therefore, for improving the detection accuracy of the angle sensor 1, it is preferable to have a smaller range of obliqueness of the electromagnetic wires 21 within the gap 46 relative to the direction parallel to the axis x. Furthermore, the less deviation the shape of each of the multiple coils 20, the higher the detection accuracy of the angle sensor 1. As described above, the electromagnetic wires 21 forming the multiple coils 20 cross within the gap 46. When the crossing positions of the electromagnetic wires 21 within the multiple gaps 46 (hereinafter referred to as crossing positions P) are different, the shapes of the multiple coils 20 are different. Therefore, in order to improve the detection accuracy of the angle sensor 1, it is better to have a smaller range of the cross position P of the electromagnetic wires 21 within the gap 46.

[0060] In the angle sensor 1, the extending direction of the electromagnetic wires 21 forming multiple coils 20 is close to the direction parallel to the axis x in the gap 46, and the inclination of the electromagnetic wires 21 forming multiple coils 20 relative to the direction parallel to the axis x becomes smaller. Furthermore, in the angle sensor 1, the intersection position P of the electromagnetic wires 21 forming multiple coils 20 in the gap 46 is close to the center position in the axis x direction, and the range of the acceptable intersection position P in the axis x direction becomes smaller.

[0061] Specifically, the width g1 of gap 46 decreases. For example, the ratio of the circumferential width g1 of gap 46 to the width (width w22) along the x-axis of gap 46, i.e., the aspect ratio (g1 / w22), is a specified value. Specifically, for example, the aspect ratio (g1 / w22) is less than 1 / 2 (g1 / w22 < 1 / 2) or less than or equal to 1 / 3 (g1 / w22 ≤ 1 / 3). It should be noted that, as... Figure 10 , Figure 15 As shown, the width w22 is the width of the spoke 12 in the x-direction along the axis, and is the distance between end 13c and end 13d in the x-direction along the axis. Furthermore, for example, the width g1 of the gap 46 is small enough that the electromagnetic wire 21 forming a plurality of coils 20 passing through the gap 46 will not be compressed by the two circumferentially adjacent spokes 12.

[0062] Therefore, the inclination of the electromagnetic wire 21 forming multiple coils 20 in the gap 46 relative to the direction parallel to the axis x decreases, and the direction in which the electromagnetic wire 21 extends in the gap 46 approaches the direction parallel to the axis x. Furthermore, in the gap 46, the movement of the electromagnetic wire 21 forming multiple coils 20 between two adjacent spokes 12 in the circumferential direction is restricted. This also reduces the inclination of the electromagnetic wire 21 forming multiple coils 20 in the gap 46 relative to the direction parallel to the axis x, and makes the direction in which the electromagnetic wire 21 extends in the gap 46 approach the direction parallel to the axis x.

[0063] Furthermore, the intersection position P of the electromagnetic wires 21 forming multiple coils 20 in the gap 46 is located at the center position (hereinafter referred to as the central position P0) between the position of the portion of the electromagnetic wire 21 along the end 13c of the spoke 12 and the position of the portion of the electromagnetic wire 21 along the end 13d of the spoke 12 in the x-direction. The positions of these positions are within a specified range (range Δ) in each direction of the x-direction (refer to...). Figure 15 The specified range Δ is, for example, 20% of the width (width w22) in the x-direction of the axis between the central position P0 and each side of the coil 20. Alternatively, the specified range Δ can also be, for example, 10% of the width (width w22) in the x-direction of the axis between the central position P0 and each side of the coil 20. Therefore, deviations in the output signals of the multiple coils 20 can be suppressed, improving the detection accuracy of the angle sensor 1 and the detection accuracy of the rotation angle of the rotor 2.

[0064] On the other hand, the intersection position P of the electromagnetic wires 21 forming the plurality of coils 20 in the gap 46 is not limited to the central position P0 in the x-axis direction, but can be arranged at any position. Specifically, the intersection position P can be arranged at any position as long as it is within the range of the width w22. In the past, there was a problem that the area of ​​the portion surrounded by the coils was deviated. However, in the angle sensor using the present invention, the width g1 of the gap 46 is set to the above-mentioned range, so the deviation of the area of ​​the portion surrounded by the coils can be reduced. As a result, the deviation of the output signals output by the plurality of coils 20 can be suppressed, the detection accuracy of the angle sensor 1 can be improved, and the detection accuracy of the rotation angle of the rotor 2 can be improved.

[0065] Furthermore, according to the embodiment of the present invention, the angle sensor 1 can make the extension direction of the electromagnetic wires 21 forming the plurality of coils 20 in the gap 46 approach the direction parallel to the axis x, thereby reducing the tilt of the electromagnetic wires 21 forming the plurality of coils 20 in the gap 46 relative to the direction parallel to the axis x. Therefore, the deviation of the output signals output by each of the plurality of coils 20 can be suppressed, the detection accuracy of the angle sensor 1 can be improved, and the detection accuracy of the rotation angle of the rotor 2 can be improved.

[0066] In this way, the angle sensor 1 according to an embodiment of the present invention can improve detection accuracy.

[0067] Furthermore, in each protrusion 10 of the angle sensor 1, the end 14a of the wall 11 and the end 13a of the spoke 12 are formed as radially continuous surfaces. The end 13a of the spoke 12 does not form a groove recessed into the protrusion 10 relative to the end 14a of the wall 11. Similarly, the end 14b of the wall 11 and the end 13b of the spoke 12 are formed as radially continuous surfaces. The end 13b of the spoke 12 does not form a groove recessed into the protrusion 10 relative to the end 14b of the wall 11. Therefore, the electromagnetic wire 21 wound on the spoke 12 is not locked at the ends 13a and 13b. To this end, each protrusion 10 extends a surface 15b and 15c that form a step between the ends 13c and 13d of the spoke 12 and the ends 14c and 14d of the wall 11. The surfaces 15b and 15c are walls with an inner circumferential side relative to the ends 13c and 13d of the spoke 12. Thus, the electromagnetic wire 21 wound on the spoke 12 is positioned and locked at its ends 13c and 13d opposite to and onto surfaces 15b and 15c. Therefore, even if the ends 14a and 14b of the wall 11 and the ends 13a and 13b of the spoke 12 form radially continuous surfaces, the electromagnetic wire 21 wound on the spoke 12 will be locked onto surfaces 15b and 15c, making it easy to wind the electromagnetic wire 21 onto the spoke 12. Furthermore, multiple coils 20 are stably mounted on the stator 3.

[0068] In the above embodiments, the case where the stator 3 has a cylindrical portion, namely the cylindrical portion 41, and the stator 3 has a continuous annular shape in the circumferential direction has been described, but the shape of the stator 3 is not limited to this. Figure 16 This is a perspective view showing a modified example of stator 3. For example, as shown... Figure 16 As shown, the stator 3 can also be arc-shaped, or it can extend only a portion of the circumference of the stator 3 described above. The stator 3 in the modified example is formed of the same material as the stator 3 described above. The stator 3 in the modified example is, for example, formed of an insulating resin component. Hereinafter, the stator 3 in the modified example will be described in detail. It should be noted that, regarding the structure of the stator 3 in the modified example, structures that are the same as or have the same function as the stator 3 described above are referred to by the same reference numerals, and their descriptions are omitted.

[0069] like Figure 16 As shown, specifically, for example, in a modified example, the stator 3 replaces the cylindrical tube 41 with a portion (hereinafter referred to as the arc portion) 41A that extends in an arc shape or approximately an arc shape corresponding to a portion of the circumferential area of ​​the cylindrical tube 41. Figure 16As shown, a plurality of protrusions 10 are arranged on the inner peripheral surface 42 of the arc portion 41A, similar to those of the stator 3 described above. The arc portion 41A has multiple protrusions 10 formed in a manner corresponding to the portion of the cylindrical portion 41. In the modified stator 3, a detection coil and an excitation circuit are provided. The detection coil, like the detection coil (coil structure 6) provided in the stator 3 described above, is formed by multiple coils 20. Specifically, the multiple coils 20 are arranged such that portions of coil structures 6a and 6b are respectively formed in the portion of the cylindrical portion 41 corresponding to the arc portion 41A. In the modified stator 3, similar to the multiple coils 20 in the stator 3 described above, the multiple coils 20 are also formed by winding conductive components such as electromagnetic wire around the protrusions 10. The excitation circuit, like the excitation circuit 7 described above, is a magnetic circuit that generates periodically changing magnetic flux acting on the multiple coils 20 formed in the arc portion 41A.

[0070] Furthermore, similar to the stator 3 described above, the modified stator 3 also includes a mounting portion 44 for mounting to an external device intended for use. In the modified stator 3, the mounting portion 44 is provided, for example, at both ends of the arc portion 41A in the circumferential direction. Additionally, the modified stator 3 is fitted with or fixed a circuit device (not shown) having a circuit section and an arithmetic section, such as an IC (integrated circuit). Specifically, for example, similar to the stator 3 described above, the modified stator 3 includes a holding portion 45 for accommodating the circuit device. The circuit device may also be located at one end of the stator in the circumferential direction. In this case, a large area can be provided for mounting the excitation circuit and the detection coil, which helps improve detection accuracy. Furthermore, the circuit device may be adjacent to the excitation circuit or the detection coil in the circumferential direction. In other words, in the circumferential direction, the circuit device is arranged between the detection coil or the excitation circuit and the mounting portion 44. In this case, the limited space of the stator 3 can be effectively utilized, thus contributing to the miniaturization of the angle sensor 1.

[0071] Furthermore, in both the stator 3 described above and the stator 3 in the modified example, the stator 3 and the circuit device can be sealed using an insulating resin component or the like. In this case, the resin can protect the stator 3 and the circuit device from foreign objects or the like.

[0072] Furthermore, both the stator 3 described above and the stator 3 in the modified example can be equipped with a connector that can be electrically connected to an external device. The connector can also be arranged adjacent to the circuit device. In this case, the circuit device can be connected to the connector via the shortest path, which can help to miniaturize the angle sensor 1.

[0073] The present invention has been described above through the above embodiments, but 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 or improvements can be made to the above embodiments. It is evident from the claims that such modifications or improvements can also be included within the technical scope of the present invention.

[0074] The embodiments described above are for ease of understanding of the present invention and are not intended to limit the scope of the invention. Furthermore, the above embodiments do not limit the scope of application of the present invention; the present invention can include all objects as its users. The components, their configurations, materials, conditions, shapes, and dimensions, etc., included in the above embodiments are not limited to those illustrated and can be appropriately modified. For example, the present invention includes manufacturing tolerances and other differences arising during implementation. Furthermore, components shown in different embodiments can be partially substituted or combined with each other to the extent that they do not create technical inconsistencies. Additionally, the various structures can be appropriately and selectively combined to achieve at least some of the aforementioned problems and effects.

[0075] For example, in each protrusion 10, the shape of the surface formed by the end 14a of the wall 11 and the end 13a of the spoke 12 is not limited to the shape described above. Similarly, in each protrusion 10, the shape of the surface formed by the end 14b of the wall 11 and the end 13b of the spoke 12 is not limited to the shape described above.

[0076] Specifically, for example, in each protrusion 10, the radially extending ends 14a and 14b of the wall 11 and the radially extending ends 13a and 13b of the spokes 12 may not extend continuously in the radial direction. That is, in each protrusion 10, the radially extending ends 14a and 14b of the wall 11 and the radially extending ends 13a and 13b of the spokes 12 may not be flush. Specifically, for example, in each protrusion 10, the end 13a of the spokes 12 may be located in the circumferential direction closer to the inside of the protrusion 10 (towards the opposite end 13b) than the end 14a of the wall 11, forming a groove that is recessed in the circumferential direction towards the inside of the protrusion 10 relative to the end 14a of the wall 11. Similarly, in each protrusion 10, the end 13b of the spoke 12 is located on the inner side of the protrusion 10 in the circumferential direction (the opposite end 13a side) to the end 14b of the wall 11, forming a groove that is recessed in the circumferential direction toward the inner side of the protrusion 10 relative to the end 14b of the wall 11.

[0077] Explanation of reference numerals in the attached figures

[0078] 1: Angle sensor; 2: Rotor; 3: Stator; 4: Conductor structure; 5: Conductor; 6: Coil structure; 6a, 6b: Coil structure pieces; 7: Excitation circuit; 10: Protrusion; 11: Wall; 12: Spoke; 12a: Front end; 13a, 13b, 13c, 13d, 14a, 14b, 14c, 14d: Ends; 15a, 15b; 15c: Surface; 16a, 16b: Recess; 20, 20a, 20b: Coil; 21, 21a, 21b : Electromagnetic wire; 21a1, 21a2, 21b1, 21b2: End; 30: Cylinder; 31: Inner circumferential surface; 32: Outer circumferential surface; 33, 34: End face; 41: Cylinder section; 41a, 41b: Side surface; 42: Inner circumferential surface; 43: Outer circumferential surface; 44: Assembly part; 44a: Through hole; 45: Holding part; 46, 47: Gap; g1, g2: Width; w11, w12, w21, w22: Width; P: Cross position; P0: Central position; x: Axis.

Claims

1. An angle sensor comprising: a plurality of walls extending in a direction of an axis of rotation; a plurality of spokes coupled to the plurality of walls; and a plurality of coils wound on the plurality of spokes, the plurality of coils being opposed to the plurality of walls in a radial direction, the width of the walls being the same as or greater than the width of the spokes in a circumferential direction.

2. The angle sensor according to claim 1, wherein a gap between two adjacent ones of the plurality of spokes in the circumferential direction is smaller in width than the width of the spokes.

3. The angle sensor according to claim 1 or 2, wherein an end portion of the wall extending in the radial direction and an end portion of the spoke extending in the radial direction extend continuously in the radial direction. ​ ​ ​ ​ ​ ​ ​

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