Fixed ring, rotating electric machine, and resolver rotor

Abstract

The fixing ring comprises multiple narrow portions, wide portions, and first pieces. The narrow portions are located on the parallel, opposing first and second annular surfaces, and are the narrowest when viewed from the outer periphery in the inward direction of the normal to the outer periphery. The wide portions are located on the first and second surfaces, and are wider than the widths of the narrow portions. The first pieces are located on each wide portion and are elastically deformable starting from a first curved portion that bends towards the first surface. In the mapped shape projected onto a virtual plane parallel to the first surface, the first curved portion of each first piece intersects a straight line passing through the point of tangency of the circumscribed circle corresponding to the outer periphery of the wide portion containing the first piece, and the center point of the circumscribed circle. Each first piece is located between the inscribed circle corresponding to the inner periphery of the first piece and the first curved portion.

Description

Technical Field

[0001] Embodiments of the present invention relate to a fixed ring, a rotary electric motor, and a rotary transformer rotor. Background Technology

[0002] In rotary electric machines, rotation angle sensors are widely used to detect the rotation angle of the rotating shaft. One type of rotation angle sensor, the rotary transformer, is constructed, for example, comprising a rotary transformer rotor that is fixed to and rotates integrally with the rotating shaft of the rotary electric machine, and a rotary transformer stator disposed opposite to the outer periphery of the rotary transformer rotor. This rotary transformer measures the change in the opposing interval (gap) between the rotary transformer rotor and the rotary transformer stator to detect the rotation angle of the rotating shaft.

[0003] To improve the accuracy of rotation angle detection, the rotary transformer needs to minimize the displacement of the rotor itself relative to the rotor axis of rotation. For example, conventional methods involve forming a keyway on the rotating shaft and setting a key shape on the rotor to position the rotor circumferentially. Alternatively, after the rotor is fitted with a gap in the rotating shaft, components such as collars are pressed into the shaft to press the rotor axially, thereby suppressing axial displacement. Furthermore, the frictional force generated between the collars and other components and the rotor can also suppress circumferential and radial displacement of the rotor.

[0004] On the other hand, when positioning the rotary transformer rotor by pressing it axially with a specified component that presses into the rotating shaft, it is necessary to properly adjust the load (pressing force) that acts to suppress the displacement of the rotary transformer rotor relative to the rotating shaft.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2007-64870 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] Therefore, a rotary transformer rotor capable of suppressing displacement of the rotary transformer rotor relative to the rotating shaft and capable of appropriately adjusting the load used for positioning and fixing the rotary transformer rotor is provided, along with a rotary motor having a rotary transformer rotor fixed by the fixed ring, and a rotary transformer rotor capable of performing displacement suppression and load adjustment as described above.

[0010] Methods used to solve problems

[0011] The fixing ring in this embodiment includes multiple narrow portions, wide portions, and first pieces. The narrow portions are located on parallel, opposing annular first and second surfaces, and are narrowest when viewed from the outer periphery connecting the outer periphery of the first and second surfaces in the inward normal direction to the outer periphery. The wide portions are located on the first and second surfaces, and their width is greater than the width of each narrow portion. The first pieces are located on each wide portion and are elastically deformable in the normal direction of the wide portion, starting from a first curved portion that bends towards the first surface. In a mapped shape projected onto a virtual plane parallel to the first surface, the first curved portion of each first piece intersects a straight line passing through the point of tangency of the circumscribed circle corresponding to the outer periphery of the wide portion containing the first piece and the center point of the circumscribed circle. In this mapped shape, each first piece is located between the inscribed circle corresponding to the inner periphery of the first piece and the first curved portion. Attached Figure Description

[0012] Figure 1 This is a perspective view of the rotor of a rotary electric motor having a fixed ring with an embodiment.

[0013] Figure 2 This is a schematic cross-sectional view of the rotor of a rotary electric machine having a fixed ring with an embodiment.

[0014] Figure 3 This is a perspective view of the retaining ring, which is a schematic representation of the embodiment.

[0015] Figure 4 The diagram is a schematic representation of the mapped shapes of the various parts of the fixing ring in the embodiment projected onto a virtual plane.

[0016] Figure 5 It is Figure 3 The image shows a partial enlargement of the retaining ring, and a schematic three-dimensional view of the protrusion.

[0017] Figure 6 This is a perspective view schematically illustrating an example of a modified example in which a rib is provided on the protrusion in the retaining ring of the embodiment.

[0018] Figure 7 This is a perspective view showing an example of one embodiment of a rotary transformer rotor assembly in which a fixed ring is configured as the rotor of a rotary transformer. Detailed Implementation

[0019] The following is for reference Figures 1 to 7The fixed ring, rotating electric motor, and rotary transformer rotor of the embodiment will be described. The fixed ring is one of the components of the rotating electric motor and is a component used to fix the rotary transformer rotor to the rotating shaft of the rotating electric motor. Various electric motors, generators, etc., can be used as rotating electric motors, but in this embodiment, an internal rotor type generator is used as an example. The rotary transformer rotor is a component of the rotary transformer that detects the rotational state of the rotating body. The rotary transformer is a rotation angle sensor that detects the rotation angle as the rotational state of the rotating body, and its main components include the rotary transformer rotor and the rotary transformer stator. In this embodiment, the rotary transformer rotor is a component that is fixed to the rotating shaft of the rotating electric motor and rotates integrally with the rotating shaft. The rotary transformer stator is a component that is disposed opposite to the outer periphery of the rotary transformer rotor and does not move relative to the rotary transformer rotor. Thus, the rotary transformer measures the change in the opposing interval (gap) between the rotary transformer rotor and the rotary transformer stator to detect the rotation angle of the rotating shaft.

[0020] exist Figure 1 and Figure 2 The rotor 10 of the rotary electric motor of this embodiment is shown in a schematic diagram. Figure 1 This is a three-dimensional view that roughly represents the rotor 10. Figure 2 This is a schematic cross-sectional view of the rotor 10.

[0021] like Figure 1 and Figure 2 As shown, the rotary electric machine comprises a cylindrical stator (not shown) and a generally cylindrical rotor 10 disposed inside the stator. The rotor 10 and the stator are positioned concentrically with the axis C of the rotation shaft S, and rotate together with the rotation shaft S around the axis C. In the following description, the direction along the axis C of the rotation shaft S in the rotary electric machine is defined as the axial direction, and the direction about the axis C is defined as the circumferential direction. The circumferential direction corresponds to the rotation direction of the rotation shaft S. Furthermore, the direction orthogonal to both the axial and circumferential directions is defined as the radial direction, with the side closer to the axis C in the radial direction designated as the inner side, and the side farther away designated as the outer side.

[0022] The rotary transformer rotor 1 is constructed by stacking multiple plate-shaped components (hereinafter referred to as rotary transformer rotor components) 2. The rotary transformer rotor components 2 are constructed by forming steel plates into rings of the same shape and size, each having a circular opening 21 at its center. The rotary transformer rotor components 2 are stacked with the openings 21 connected concentrically. Thus, by stacking the rotary transformer rotor components 2 and connecting the openings 21, a through hole 1a is formed at the center of the rotary transformer rotor 1. The diameter (inner diameter) of the opening 21 is a size that allows it to be fitted with the outer periphery of the rotating shaft S. Therefore, the through hole 1a of the rotary transformer rotor 1 fits snugly into the outer periphery of the rotating shaft S, allowing it to be mounted on the rotating shaft S.

[0023] Furthermore, the outline of the outer periphery of the rotary transformer rotor assembly 2 (hereinafter referred to as the outer periphery shape) is non-circular, causing the gap with the rotary transformer stator to vary. For example, the rotary transformer rotor assembly 2 has an outer periphery shape with multiple wide portions 22 arranged circumferentially, having the same curvature that is greater than the inner periphery of the opposing rotary transformer stator. Adjacent wide portions 22 in the circumferential direction are continuous via narrow portions 23. The narrow portions 23 are the parts where the outer periphery shape of the rotary transformer rotor assembly 2 is concave and the diameter of the outer periphery shape formed by adjacent wide portions 22 is the smallest. That is, the rotary transformer rotor assembly 2 has a planar shape in which wide portions 22 and narrow portions 23 alternately continue, and the outer periphery shapes of each wide portion 22 and narrow portion 23 alternately continue. In this embodiment, as an example, four wide portions 22 and four narrow portions 23 are provided, arranged symmetrically about the axis C. However, these numbers are not particularly limited. Alternatively, the rotor assembly 2 of the rotary transformer may also have a key on a portion of its inner periphery that engages with the keyway S3 of the rotating shaft S, which will be described later.

[0024] In a rotary transformer, by rotating the rotary transformer rotor 1 relative to the rotary transformer stator, the gap between the two can be changed periodically. At this time, based on the change in gap, the rotation angle of the rotating shaft S on which the rotary transformer rotor 1 is mounted is detected. For example, during the rotation of the rotating shaft S, when a magnetic field is formed by current flowing through the coil wound on the rotary transformer stator, the rotary transformer rotor 1 rotates in this magnetic field. Therefore, by detecting the change in magnetic flux at this time, the rotation angle of the rotating shaft S can be detected. Thus, the rotary transformer, consisting of the rotary transformer rotor 1 and the rotary transformer stator, outputs a rotation angle signal to the control device (not shown) corresponding to the rotation angle of the rotary transformer rotor that rotates along with the rotation of the rotating shaft S. Therefore, the control device performs rotation control of the rotary motor based on the output rotation angle signal.

[0025] The rotor 1 of the rotary transformer is axially supported by the seat surface S1 of the rotating shaft S, with the through hole 1a gap fitting into the outer circumference of the rotating shaft S. For example... Figure 2 As shown, the seat surface S1 is a stepped portion created by the diameter difference between the major and minor diameter portions of the outer periphery of the rotating shaft S, and is a continuous annular planar portion throughout the circumference. Figure 2 In the example shown, the axial end face of the rotary transformer rotor 1 (in) Figure 2 The lower surface (hereinafter referred to as end face) 1b abuts against and contacts the seat face S1. In this case, with the rotary transformer rotor 1 pressed into the rotating shaft S from above through hole 1a, one end face 1b abuts against the seat face S1.

[0026] With one end face 1b in contact with the seat face S1, the rotary transformer rotor 1 is supported by the fixed component 3 relative to the rotation shaft S.

[0027] Figure 3 This is a schematic perspective view of the fixed component 3. (For example...) Figure 2 and Figure 3 As shown, the fixing component (hereinafter referred to as the fixing ring) 3 is a ring-shaped component that can be pressed into the rotating shaft S, and is used to position and fix the rotary transformer rotor 1 between itself and the seat surface S1. In order to suppress changes in the fixed state of the rotary transformer rotor 1 caused by temperature changes, the fixing ring 3 can be made of a material with the same coefficient of linear expansion as the rotating shaft S, for example, but the specific material is not particularly limited.

[0028] like Figure 3 As shown, the fixing ring 3 has an annular flat plate portion 30 and two types of protruding portions provided on the flat plate portion 30. The flat plate portion 30 extends along the axial end face (hereinafter referred to as the other end face) 1c of the rotary transformer rotor 1. The other end face 1c is the surface opposite to the axial end face 1b. Figure 2 In the example shown, the upper surface is the plate portion 30. With the retaining ring 3 pressed into the rotating shaft S and the rotary transformer rotor 1 positioned and fixed, the plate portion 30 contacts the other end face 1c. In this state, the outline (outer peripheral shape) of the outer periphery of the plate portion 30 is a non-circular shape that is one size smaller than the outer peripheral shape of the rotary transformer rotor 1. This prevents the outer periphery of the plate portion 30 from protruding from the outer periphery of the rotary transformer rotor 1, thus suppressing the impact on the detection accuracy of the magnetic flux change detected by the rotary transformer, i.e., on the rotation angle detection accuracy of the rotating shaft S.

[0029] The flat plate portion 30 has a narrow portion 30b and a wide portion 30a. The narrow portion 30b is respectively provided on the first surface 301 and the second surface 302 of the parallel-opposite flat plate portion 30, and is the narrowest part when viewed from the outer peripheral surface 303 in the inward normal direction. The normal direction is equivalent to the radial direction. The outer peripheral surface 303 of the flat plate portion 30 is the surface connecting the outer periphery of the first surface 301 and the outer periphery of the second surface 302. The wide portion 30a is provided on the first surface 301 and the second surface 302 of the flat plate portion 30, and is a portion wider than the narrow portion 30b. The first surface 301 and the second surface 302 are the end faces at both ends in the axial direction, and the second surface 302 is the surface that contacts the other end face 1c of the rotary transformer rotor 1.

[0030] The wide portion 30a has an outer peripheral shape that bends circumferentially with the same curvature as the wide portion 22 of the rotary transformer rotor assembly 2. Adjacent wide portions 30a in the circumferential direction are continuous via narrow portions 30b. The narrow portion 30b is the part where the outer peripheral shape of the flat plate portion 30 is concave, and the diameter of the outer peripheral shape formed by adjacent wide portions 30a is the smallest. That is, the flat plate portion 30 has a planar shape with alternating continuous wide portions 30a and narrow portions 30b. In this embodiment, as an example, each of the wide portions 30a and narrow portions 30b has four, the same number as the rotary transformer rotor assembly 2, and is arranged symmetrically around the axis C. However, these numbers are not particularly limited and may not be consistent with the rotary transformer rotor assembly 2.

[0031] The flat plate portion 30, as a protruding part in two forms, has multiple first pieces 31 and multiple second pieces 32. The first pieces 31 and second pieces 32 function as spring pieces relative to the flat plate portion 30. Figure 3 In the example shown, four first plates 31 and eight second plates 32 are provided on the plate portion 30. However, these numbers are not limited to this.

[0032] Each of the first sheet portions 31 has a first curved portion 31x on each of the width portions 30a, which is capable of elastic deformation starting from a first curved portion 31x that bends toward the first surface 301 of the flat plate portion 30. Thus, each first sheet portion 31 elastically deforms from the outer peripheral surface 303 of the width portion 30a toward the inward normal direction of the outer peripheral surface 303, or more specifically, inward radially, starting from the first curved portion 31x. That is, the first sheet portion 31 functions as a spring sheet.

[0033] Figure 4 This diagram is a simplified representation of the mapped shapes of the various parts of the fixed ring 3 projected onto a virtual plane. Figure 4 In the defined mapping shape shown, the first curved portion 31x of each first piece 31 intersects the straight line L31 passing through the tangent point P31 of the circumscribed circle O31 corresponding to the outer periphery of the width portion 30a on which the first piece 31 is located, and the center point of the circumscribed circle O31. The defined mapping shape is the shape of projecting multiple width portions 30a, multiple first pieces 31, and multiple second pieces 32 onto a virtual plane parallel to the first surface 301 of the flat plate portion 30. In the following description, it is referred to as the mapping shape on the virtual plane. The center point of the circumscribed circle O31 is the intersection of the axis C and the virtual plane. In addition, in the mapping shape, each first piece 31 is located between the inscribed circle I31 corresponding to the inner periphery of the first piece 31 and the first curved portion 31x. The center point of the inscribed circle I31 is the intersection of the axis C and the virtual plane.

[0034] The first piece 31 has a contact portion 31a that contacts the outer peripheral surface S2 of the rotating shaft S. The contact portion 31a is the radially extending front end (protruding end) of the first piece 31. When the retaining ring 3 is pressed into the rotating shaft S, the first piece 31 contacts the outer peripheral surface S2 through the contact portion 31a, and is thus pressed by the outer peripheral surface S2, elastically deforming relative to the flat plate portion 30 in a warping manner. Moreover, in the state where the retaining ring 3 positions and fixes the rotary transformer rotor 1, in other words, in the state where the flat plate portion 30 contacts the other end face 1c of the rotary transformer rotor 1, the contact portion 31a presses the outer peripheral surface S2 with the restoring force of the elastic deformation of the first piece 31. Thus, the first piece 31 supports the retaining ring 3 (more specifically, the flat plate portion 30) in the radial and axial directions relative to the rotating shaft S, and is positioned and fixed.

[0035] The contact method between the contact portion 31a and the outer peripheral surface S2 is such that the closer the contact is to a point contact, the more concentrated the pressing force is from the contact portion 31a to the outer peripheral surface S2. Therefore, in order to more stably position the retaining ring 3 relative to the rotation axis S, it is preferable that the contact portion 31a makes line contact or point contact with the outer peripheral surface S2, rather than surface contact. From this point of view, in this embodiment, the contact portion 31a is formed into a concave shape with a curvature greater than that of the outer peripheral surface S2. Thus, the contact portion 31a contacts the outer peripheral surface S2 at its two circumferential ends 31b and 31c (approximately point contact).

[0036] exist Figure 4 In the mapped shape on the virtual plane shown, the first curved portion 31x of each first piece 31 intersects the straight line L31. That is, the portion where the width (difference between outer and inner diameter) of the first piece 31 and the radially flat plate portion 30 is the largest, i.e., the portion that protrudes (bulges) radially outward in the wide portion 30a, is overlapped in the wide portion 30a when viewed radially on the virtual plane. As a result, the width of the flat plate portion 30 in the first curved portion 31x, which is the starting point when the first piece 31 elastically deforms relative to the flat plate portion 30, can be maximized. Thus, the portion of the wide portion 30a that overlaps with the first piece 31 corresponds to the portion with the largest cross-sectional area of ​​the flat plate portion 30 on the plane defined by the radial and axial directions. Therefore, even if, for example, the width (radial length) of the first piece 31 is increased, the width of the flat plate portion 30 can be maximized, and the reduction in the strength of the retaining ring 3 can be suppressed.

[0037] like Figure 3 As shown, the retaining ring 3 (flat plate portion 30) of this embodiment has four first plates 31. Figure 4In the mapped shape on the virtual plane shown, one of the plurality of first portions 31 (first portion 311) has a protrusion (second protrusion) 312 that radially protrudes from the inner side of the inscribed circle I31 corresponding to the inner periphery of the other first portions 31. The protrusion 312 is a key (hereinafter referred to as key 312) that prevents the fixed ring 3 from rotating relative to the rotation axis S and positions the fixed ring 3 circumferentially, in other words, in the rotational direction of the rotation axis S. Therefore, a keyway S3 corresponding to the key 312 is formed on the rotation axis S. When pressed into the rotation axis S, the fixed ring 3 is aligned circumferentially by the engagement of the key 312 and the keyway S3.

[0038] like Figure 3 As shown, key 312 is located approximately in the middle of the circumferential direction of the contact portion 31a of the first piece 311, and protrudes radially from both ends 31b and 31c of the circumferential direction of the contact portion 31a, i.e., from the contact portion with the outer peripheral surface S2 of the rotating shaft S, by an amount corresponding to the depth of the keyway S3. Figure 4 In the mapped shape on the virtual plane shown, key 312 highlights the difference between the radius r2 of the inscribed circle I31 and the radius r1 of the inscribed circle I312 corresponding to the inner periphery of key 312. Since key 312 only needs to position the fixing ring 3 relative to the rotation axis S in the circumferential direction, it is only necessary to position the two ends 313 in the circumferential direction with... Figure 1 The keyway S3 shown can be in contact with the groove wall S31, and the front end (protruding end) 314 may not need to contact the groove bottom S32. In addition, the key 312 and the keyway S3 can be omitted, or multiple keys can be provided.

[0039] like Figure 3 As shown, the second piece 32 is disposed adjacent to the first piece 31 of each width portion 30a in the circumferential direction of the first surface 301 and the second surface 302 of the flat plate portion 30, and can elastically deform starting from the second curved portion 32x that bends toward the second surface 302 of the flat plate portion 30. Figure 3 In the example shown, the second piece 32 has a base end portion 32a and a contact portion 32b, and is configured as a spring piece capable of elastically deforming the contact portion 32b relative to the base end portion 32a. A second bent portion 32x is provided at the base end portion 32a.

[0040] exist Figure 4 In the mapped shape on the virtual plane shown, each second piece 32 is located outside the inscribed circle I31 corresponding to the inner periphery of the first piece 31 adjacent to it. Furthermore, the second piece 32 is disposed near the first piece 31. In this embodiment, the base end portion 32a and the first piece 31 are not directly continuous in the circumferential direction, but are disposed at a predetermined interval. Figure 3On the fixed ring 3 shown, a second piece 32 is arranged on each side of the circumference, separated by a first piece 31. A spring sheet, consisting of these first pieces 31 and the second pieces 32 on both sides, is arranged on the flat plate 30, for example, to match the arrangement of the magnetic poles of a rotary transformer. Figure 3 In the example shown, the four sets of elements are matched with the magnetic pole configuration of the rotary transformer, in other words, configured according to each pole of the rotary transformer rotor 1.

[0041] exist Figure 4 In the mapped shape on the virtual plane shown, the base end portion 32a extends parallel to the inner periphery of the plate portion 30 towards... Figure 1 The outer circumferential surface S2 of the rotating shaft S shown is, more specifically, the extension of the axis C. The radially extending protruding length of the base end portion 32a is shorter than the radially extending protruding length of the first plate portion 31 by an amount that extends parallel to the inner circumference of the plate portion 30 and is not inclined relative to the plate portion 30.

[0042] The contact portion 32b extends circumferentially from the base end portion 32a in a direction away from the adjacent first plate portion 31. Furthermore, the contact portion 32b extends obliquely towards the second surface 302 relative to the base end portion 32a, specifically the flat plate portion 30, in a manner approaching the other end face 1c of the rotary transformer rotor 1. Figure 3 In the example shown, the first plate portion 31 is inclined upward in the axial direction, while the contact portion 32b is inclined downward in the axial direction. That is, the contact portion 32b is inclined in the opposite direction to the axial direction of the first plate portion 31. The width (radial length) of the radially extending contact portion 32b is smaller than the radially extending protruding length of the base end portion 32a. The contact portion 32b extends radially away from the inner circumference of the plate portion 30 and extends away from the outer circumferential surface S2 of the rotation axis S. The contact portion 32b extending in this way is configured as a spring plate that can elastically deform relative to the base end portion 32a, starting from the second curved portion 32x, which is a curved portion that bends from the base end portion 32a.

[0043] When the retaining ring 3 is pressed into the rotating shaft S, the contact portion 32b contacts the other end face 1c of the rotary transformer rotor 1, and is thus pressed by the other end face 1c, elastically deforming relative to the base end 32a in an upward warping manner. Furthermore, with the flat plate portion 30 in contact with the other end face 1c of the rotary transformer rotor 1, the contact portion 32b presses the other end face 1c using the restoring force of the elastic deformation. Thus, the contact portion 32b presses the rotary transformer rotor 1 toward the seat portion S1 of the rotating shaft S. That is, in this state, the retaining ring 3 clamps the rotary transformer rotor 1 between itself and the seat portion S1, thereby axially positioning and fixing it. Figure 1 (The state shown).

[0044] At this time, the contact portion 31a of the first piece 31 presses against the outer peripheral surface S2 of the rotating shaft S using the restoring force of elastic deformation, and absorbs the axial load (pressing force) generated by the elastic deformation of the contact portion 32b, thus suppressing the torsion and other deformations of the flat plate portion 30. Figure 3 In the example shown, since a second piece 32 is arranged on each side of the circumference with a first piece 31 in between, deformation of the flat plate 30 can be suppressed more effectively. In this case, the contact portions 32b of the second pieces 32 sandwiching the first piece 31 on both sides of the circumference extend in opposite directions in the circumference.

[0045] Thus, according to this embodiment, the fixing ring 3, having a first piece 31 and a second piece 32, can be positioned axially and radially relative to the rotation shaft S. Simultaneously, by positioning the fixing ring 3 in this way, the rotary transformer rotor 1 is clamped between the fixing ring 3 and the seat surface S1 for positioning and fixation. At this time, the restoring force of the elastic deformation of the first piece 31, i.e., the force pressing the outer peripheral surface S2 of the rotation shaft S, can absorb the force that deforms the flat plate 30 when the contact portion 32b presses against the rotary transformer rotor 1. That is, the pressing force acting from the first piece 31 and the second piece 32 can be appropriately adjusted, and the displacement of the rotary transformer rotor 1 relative to the rotation shaft S can be suppressed. Furthermore, the deformation of the flat plate 30 caused by this pressing force can be suppressed, and the contact area, in other words, the friction area, between the flat plate 30 and the other end surface 1c of the rotary transformer rotor 1 can be appropriately ensured. As a result, the displacement of the rotary transformer rotor 1 relative to the rotation shaft S can be appropriately suppressed, and the detection accuracy of the rotation angle of the rotary transformer can be improved.

[0046] To suppress displacement of the rotary transformer rotor 1 and properly position and fix it relative to the rotating shaft S, the rotating shaft S and the fixing ring 3 need to be positioned concentrically. For example, if the center of the fixing ring 3 is deviated from the axis C of the rotating shaft S, the shape of the four first pieces 31 during elastic deformation will deviate. If such a deviation occurs, the force of the contact portion 31a of each first piece 31 pressing against the outer peripheral surface S2 of the rotating shaft S will also deviate, and the pressing force will no longer act evenly. As a result, the fixing ring 3 cannot be properly supported relative to the rotating shaft S, and there is a risk that the rotary transformer rotor 1 cannot be properly positioned and fixed relative to the rotating shaft S.

[0047] Therefore, as Figures 3 to 5 As shown, the retaining ring 3 has protrusions 33 and 34 for positioning its center concentrically with the axis C of the rotating shaft S when pressed into the rotating shaft S. Figure 5 It is Figure 3The fixed ring 3 is partially enlarged, and a perspective view of the protrusions 33 and 34 is shown in a general sense. Unlike the first piece 31 and the second piece 32, the protrusions 33 and 34 do not function as springs relative to the flat plate 30. Therefore, the protrusions 33 and 34 do not undergo elastic deformation relative to the flat plate 30, or they do not undergo large elastic deformation like the first piece 31 and the second piece 32, thus maintaining their original shape.

[0048] exist Figure 4 In the mapped shape on the virtual plane shown, each second piece 32 has a protrusion (first protrusion) 33 that radially protrudes from the outer side of the inscribed circle I31 corresponding to the inner periphery of the first piece 31 adjacent to the second piece 32 in the circumferential direction. In other words, the radius r3 of the inscribed circle I33 corresponding to the inner periphery of the protrusion 33 is larger than the radius r2 of the inscribed circle I31. The center point of the inscribed circle I33 is the intersection of the axis C and the virtual plane.

[0049] exist Figure 3 and Figure 5 In the example shown, the protrusion 33 is provided at the base end portion 32a of the second piece 32, and is configured as a part of the base end portion 32a. A portion of the protrusion 33 extends radially from the front end portion (extending protruding end portion) of the base end portion 32a and faces parallel to the base end portion 32a. Figure 1 The outer peripheral surface S2 of the rotating shaft S shown is, more specifically, an extension of the axis C. The radially extending protruding length of the protrusion 33 is such that it does not contact the outer peripheral surface S2 of the rotating shaft S. The radially extending front end (the protruding end) of the protrusion 33 is formed as follows: Figure 4 The outline of the mapped shape on the virtual plane is curved into a convex shape. Therefore, when the protrusion 33 is pressed into the rotation axis S at the part that protrudes (bulges) to the innermost side, it can make approximately point contact with the outer peripheral surface S2.

[0050] The base end portion 32a of the second piece 32 is positioned near the first piece 31. Therefore, if the first piece 31 undergoes elastic deformation when pressed into the rotating shaft S, the protrusions 33 of each of the second pieces 32 contact the outer peripheral surface S2 near the first piece 31. At this time, unlike the first piece 31 and the second piece 32, the protrusions 33 hardly undergo elastic deformation relative to the flat plate 30, thus fulfilling the function of positioning the center of the fixing ring 3 concentrically with the axis C of the rotating shaft S. As a result, when the fixing ring 3 is pressed into the rotating shaft S, for example, the four first pieces 31 can be elastically deformed approximately equally, and the contact portions 31a of each first piece 31 can press the outer peripheral surface S2 of the rotating shaft S approximately equally. Therefore, the fixing ring 3 can be properly supported relative to the rotating shaft S, and the rotary transformer rotor 1 can be properly positioned and fixed relative to the rotating shaft S. After the fixing ring 3 is pressed into the rotating shaft S, the protrusions 33 do not contact the outer peripheral surface S2 and are positioned in a non-contact state.

[0051] exist Figure 4 In the mapped shape on the virtual plane shown, protrusion 34 and the second piece 32 are arranged adjacent to each other in the circumferential direction. Figure 4 In the example shown, the protrusion 34 is located outside the inscribed circle I31 corresponding to the inner periphery of each first piece 31. Furthermore, the protrusion 34 is located outside the inscribed circle I33 corresponding to the inner periphery of each protrusion 33. That is, the radius r4 of the inscribed circle I34 corresponding to the inner periphery of the protrusion 34 is larger than the radius r3 of the inscribed circle I33. The center point of the inscribed circle I34 is the intersection of the axis C and the virtual plane. Thus, the protrusion 34 is a protruding portion of the flat plate 30, unlike the first piece 31 and the second piece 32. The protrusion 34 extends parallel to the inner periphery of the flat plate 30 towards... Figure 1 The outer circumferential surface S2 of the rotating shaft S shown is, more specifically, an extension of the axis C. The radially extending protrusion 34 is a dimension that does not contact the outer circumferential surface S2 of the rotating shaft S.

[0052] The protrusion 34 has an opposing portion 34a that does not contact the outer peripheral surface S2. The opposing portion 34a is the front end (extended protruding end) of the protrusion 34. The opposing portion 34a is formed, for example, into a concave shape with a curvature greater than or equal to the curvature of the outer peripheral surface S2.

[0053] The protrusion 34 is arranged to include a narrow portion 30b, so that it overlaps with the portion of the flat plate 30 in the radial direction where the width (difference between outer and inner diameters) is smallest, i.e., the narrow portion 30b, when viewed radially in a virtual plane. Thus, the portion of the flat plate 30 overlapping with the protrusion 34 corresponds to the portion of the flat plate 30 in a predetermined plane defined by the radial and axial directions where the cross-sectional area is smallest. Therefore, by arranging the protrusion 34 at this portion, the cross-sectional area is correspondingly increased, thereby improving the strength of the flat plate 30, and more specifically, the retaining ring 3. Figure 3 In the example shown, four protrusions 34 are provided, arranged in a point-symmetric configuration around the axis C. In this case, each protrusion 34 is positioned between the four sets of elements described above, which are respectively composed of the first piece 31 and the second pieces 32 on both circumferential sides of it. However, the number of protrusions 34 is not limited. Furthermore, if the retaining ring 3 can maintain appropriate strength, the protrusions 34 can be omitted.

[0054] In addition, to further improve the strength of the retaining ring 3, a reinforcing part can be provided on the protrusion 34. Figure 6 The accompanying drawing schematically shows an example of a modified retaining ring 3a in which a reinforcing portion 35 is provided on the protrusion 34. Furthermore, the configuration of the retaining ring 3a, except for the reinforcing portion 35, is the same as that of the retaining ring 3; therefore, the same reference numerals are used in the drawing and descriptions are omitted. Figure 6In the example shown, the reinforcing part 35 is located at the front end of the protrusion 34, i.e., the opposing part 34a, and rises axially from the opposing part 34a in the direction of the distance between the first surface 301 and the second surface 302 of the flat plate part 30. Thus, the reinforcing part 35 functions as a rib to increase the strength of the retaining ring 3, particularly near the narrow portion 30b of the flat plate part 30. The direction in which the reinforcing part 35 rises is away from the other end face 1c of the rotary transformer rotor 1 (upward in this embodiment).

[0055] The embodiments (including variations) of the present invention have been described above, but these embodiments are provided as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope or spirit of the invention, and are included in the scope of the invention and its equivalents as described in the claims.

[0056] In the above embodiment, the rotary transformer rotor 1 and the fixed ring 3 are constructed separately. Alternatively, the fixed ring may be constructed as one of the rotary transformer rotor components.

[0057] exist Figure 7 The image shows an example of an embodiment in which a fixed ring is configured as one of the components of a rotary transformer rotor. Figure 7 In the example shown, the rotary transformer rotor 4 is the same as the rotary transformer rotor 1, constructed by stacking multiple rotary transformer rotor components 5. However, the rotary transformer rotor component 51 located on the axially defined side is a form obtained by deforming the shape of the second piece 32 of the fixing ring 3. The axially defined side is the other end of the axial direction in the above embodiment, which is the opposite side of the side where the rotary transformer rotor 4 contacts the seat surface S1 of the rotating shaft S. In this case, the rotary transformer rotor component 51 is a form in which the contact portion 32b is omitted from the second piece 32 of the fixing ring 3. That is, the rotary transformer rotor component 51 has the same effect as the fixing ring 3 except for the contact portion 32b. In addition, for the fixing ring 3 ( Figure 3 Equivalent constituent elements shall be labeled with the same reference numerals on the accompanying drawings.

[0058] like Figure 7As shown, the rotary transformer rotor 4 is constructed by stacking multiple iron cores (hereinafter referred to as iron cores 5) that form the rotary transformer rotor component 5. Each iron core 5 has a wide portion 22 and a narrow portion 23. The narrow portion 23 is provided on the first surface 501 and the second surface 502 of the parallel-opposite iron core 5, and is the narrowest part when viewed from the outer peripheral surface 503 in the inward normal direction of the outer peripheral surface 503. The normal direction is equivalent to the radial direction. The outer peripheral surface 503 of the iron core 5 is the part connecting the outer peripheral edge of the first surface 501 and the outer peripheral edge of the second surface 502. The wide portion 22 is provided on the first surface 501 and the second surface 502 of the iron core 5, and is a part whose width is wider than the width of the narrow portion 23.

[0059] The core 5 (rotor assembly 51 of the rotary transformer) located at one end in the stacking direction has multiple first plates 31. The first plates 31 are equivalent to the first plates 31 in the retaining ring 3. One first plate 31 is provided on each of the width portions 22, and each first plate 31 is elastically deformable starting from a first bend 31x that bends towards the first surface 501 of the core 5. Thus, each first plate 31 elastically deforms from the outer peripheral surface 503 of the width portion 22 in the inward normal direction of the outer peripheral surface 503, or more specifically, in the radial inward direction, starting from the first bend 31x. That is, the first plates 31 function as spring plates.

[0060] by Figure 4 Based on the mapped shape on the virtual plane shown, in a corresponding mapped shape, the first curved portion 31x of each first piece 31 intersects the line (equivalent to the tangent point P31 of the tangent circle O31) passing through the outer periphery of the width portion 22 where the first piece 31 is located, and the center point of the tangent circle (equivalent to the line L31). This mapped shape is a shape that projects multiple width portions 22, multiple first pieces 31, and multiple second pieces 32 onto a virtual plane parallel to the first surface 501 of the core 5. Furthermore, in this mapped shape, each first piece 31 is located between the inscribed circle (equivalent to the inscribed circle I31) corresponding to the inner periphery of the first piece 31 and the first curved portion 31x. The center point of this inscribed circle is the intersection of the axis C and the virtual plane.

[0061] like Figure 7As shown, the rotary transformer rotor assembly 51, which serves as the core, has all parts except for the contact portion 32b in the fixing ring 3. Specifically, it has portions corresponding to the base end portion 32a of the first piece 31 and the second piece 32, the key 312, and the protrusions 33 and 34. Furthermore, the rotary transformer rotor assemblies 5 and 51 have a planar shape with alternating wide portions 22 and narrow portions 23, and the outer peripheral shapes of the wide portions 22 and narrow portions 23 are also alternating continuously. In the rotary transformer rotor 4, the rotary transformer rotor assembly 51 and other rotary transformer rotor assemblies 5 are integrally connected axially, for example, by riveting.

[0062] Even if the rotary transformer rotor 4 is configured to include the rotary transformer rotor component 51, the force that suppresses the displacement of the rotary transformer rotor 4 relative to the rotation axis S can be appropriately adjusted, and the rotary transformer rotor 4 can be appropriately positioned and fixed relative to the rotation axis S.

[0063] Explanation of reference numerals in the attached figures

[0064] 1, 4… Rotary transformer rotor, 1a… Through hole, 1b… One end face (lower surface), 1c… The other end face (upper surface), 2, 5, 51… Rotary transformer rotor assembly, 3… Fixing component (fixing ring), 10… Rotor, 21… Opening, 22… Wide section, 23… Narrow section, 30… Flat plate section, 30a… Wide section, 30b… Narrow section, 31, 311… First plate section, 31a… Contact section, 31x… First bend section, 32x… Second bend section , 312…protrusion (key), 32…second piece, 32a…base end, 32b…contact part, 33…protrusion, 34…protrusion, 34a…opposing part, 35…reinforcing part (rib), 301, 501…first surface, 302, 502…second surface, 303, 503…outer peripheral surface, C…axis, I31, I33, I312…inscribed circle, L31…straight line, P31…tangent point, S…rotation axis, S1…seat surface, S2…outer peripheral surface, S3…keyway.

Claims

1. A fixing ring, comprising: Multiple narrow sections are provided on parallel and opposite annular first and second surfaces, and the width is the narrowest when viewed from the outer periphery connecting the outer periphery of the first surface and the outer periphery of the second surface in the inward normal direction of the outer periphery surface. Multiple wide portions are disposed on the first surface and the second surface, and the width of the wide portions is wider than the width of each of the narrow portions; Multiple first portions are respectively disposed on each of the wide portions, and are capable of elastic deformation in the normal direction of the wide portion, starting from the first curved portion that bends toward the first surface side; as well as Multiple second portions are arranged adjacent to the first portions of each of the wide portions in the circumferential direction of the first and second surfaces, and are capable of elastic deformation in the direction of the distance between the first and second surfaces, starting from the second curved portion that bends toward the second surface. In the mapped shape where the multiple wide portions and the multiple first pieces are projected onto a virtual plane parallel to the first surface, the first curved portion of each first piece intersects a straight line passing through the point of tangency of the circumscribed circle corresponding to the outer periphery of the wide portion on which the first piece is located and the center point of the circumscribed circle. Each first piece is located between the inscribed circle corresponding to the inner periphery of the first piece and the first curved portion. The center point of the circumscribed circle and the center point of the inscribed circle are the intersection points of the axis of the fixing ring and the virtual plane. In the mapped shape that projects a plurality of first portions and a plurality of second portions onto the virtual plane, each second portion is located outside the inscribed circle corresponding to the inner periphery of the first portion adjacent to the second portion.

2. The fixing ring as described in claim 1, wherein, In the mapped shape that projects a plurality of first portions and a plurality of second portions onto the virtual plane, each second portion has a first protrusion that protrudes radially toward the inscribed circle outside the inscribed circle corresponding to the inner periphery of the first portion that is adjacent to the second portion in the circumferential direction of the first portion on the first and second surfaces.

3. The fixing ring as described in claim 1, wherein, The fixing ring also has ribs, which are arranged adjacent to the second pieces in the circumferential direction of the first and second surfaces in the mapped shape projected onto the virtual plane, and stand out in the direction of distance between the first and second surfaces from the outer side of the inscribed circle corresponding to the inner periphery of each first piece. The ribs are erected in a direction away from the first surface.

4. The retaining ring as described in any one of claims 1 to 3, wherein, In the mapped shape that projects a plurality of first portions onto the virtual plane, one of the plurality of first portions has a second protrusion that protrudes radially toward the inscribed circle corresponding to the inner periphery of the other first portions. The second protrusion is a key that prevents the fixed ring from rotating relative to the rotating shaft and positions the fixed ring in the rotational direction of the rotating shaft.

5. A rotary electric motor, comprising: The axis rotates around the central axis; The rotor is fixed concentrically with the shaft; The stator is configured opposite the rotor; and A rotary transformer rotor, having a specified number of poles, is concentrically fixed to the shaft by a retaining ring as described in claim 1, wherein... The retaining ring clamps the rotary transformer rotor between itself and the seat surface of the shaft, thereby positioning and fixing the rotary transformer rotor. The first plate and the second plate adjacent to the first plate in the circumferential direction are arranged according to each pole of the rotary transformer rotor.

6. A rotary transformer rotor, Multiple iron cores are stacked, each core having multiple narrow portions and multiple wide portions. The multiple narrow portions are disposed on parallel, opposite annular first and second surfaces, and their width is narrowest when viewed in the inward normal direction from the outer peripheral surface connecting the outer periphery of the first surface and the outer periphery of the second surface. The width of each of the multiple wide portions is wider than the width of each of the narrow portions. The iron core located at one end in the stacking direction has a plurality of first portions and a plurality of second portions. The plurality of first portions are respectively disposed in each of the width portions and are elastically deformable in the normal direction of the width portion, starting from a first curved portion that bends toward the first surface. The plurality of second portions are disposed adjacent to the first portions of each of the width portions in the circumferential direction of the first and second surfaces, and are elastically deformable in the direction of the distance between the first and second surfaces, starting from a second curved portion that bends toward the second surface. In the mapped shape projected onto a virtual plane parallel to the first surface, the first curved portion of each first piece intersects a straight line passing through the point of tangency of the circumscribed circle corresponding to the outer periphery of the first piece and the center point of the circumscribed circle. Each first piece is located between the inscribed circle corresponding to the inner periphery of the first piece and the first curved portion. The center point of the circumscribed circle and the center point of the inscribed circle are the intersection points of the axis of the rotary transformer rotor and the virtual plane. In the mapped shape that projects a plurality of first portions and a plurality of second portions onto the virtual plane, each second portion is located outside the inscribed circle corresponding to the inner periphery of the first portion adjacent to the second portion.

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