Angle sensor

Abstract

To provide an angle sensor excellent in workability, which can position both an insulator and a cover in fitting the cover to the insulator.SOLUTION: An angle sensor comprises: a rotor 10; a stator 100 facing the rotor 10 in a radial direction; an insulator 150 for covering the stator 100; a coil 157 wound around the insulator 150; and an upper cover 300 for covering the coil 157. An outer periphery of the upper cover 300 comprises a hook 322 on one side in the radial direction, the insulator 150 comprises a recess 161 for accommodating the hook 322 to engage with it in the radial direction, and the insulator 150 is fixed to the upper cover 300 on the other side in the radial direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an angle sensor such as a resolver, and more particularly to an improvement in the cover mounting structure. [Background technology]

[0002] Resolvers have been known as a means for detecting the rotation angle of rotating electrical machines such as motors and generators. A resolver is configured by fixing a stator to a casing and placing a rotor inside the stator. The stator is configured by attaching an insulator to a stator stack and winding a conductor around it.

[0003] A resolver is fitted with a cover to protect the coil around which a conductor is wound. The cover is fixed to the insulator, for example, by having a boss formed on the insulator protrude from a through-hole formed in the cover and then thermally caulking the boss.

[0004] The above-described cover fixing method requires dedicated equipment for thermally caulking the bosses. Therefore, in Patent Document 1, the insulator is formed with multiple protruding members 81 that protrude in the axial direction, and the protruding members 81 are inserted into multiple through holes 64 formed in the first annular winding protection cover 80. Claw portions 94 formed at the upper ends of the protruding members 81 are engaged with step portions 100 formed in the through holes 64, thereby attaching the first annular winding protection cover 80 to the insulator. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6531244 Summary of the Invention [Problem to be solved by the invention]

[0006] In the configuration in which the first annular winding protection cover 80 is attached to the insulator using a snap-fit ​​method as described in Patent Document 1, it is necessary to position multiple through holes 64 on multiple protruding members 81, which poses a problem of poor workability.

[0007] The present invention has been made in view of the above circumstances, and has as its object to provide an angle sensor that allows for easy positioning of the insulator and the cover when attaching them to each other, and that is easy to work with. [Means for solving the problem]

[0008] The present invention is an angle sensor comprising a rotor, a stator facing the rotor in a radial direction perpendicular to the rotational axis direction of the rotor, an insulating member covering the stator, a conductor wound around the insulating member, and a cover covering the conductor, wherein on one side of the radial direction, the outer periphery of the cover has a convexity, and the insulating member has a concaveity that accommodates the convexity and engages with it in the radial direction, and on the other side of the radial direction, the insulating member and the cover are fixed.

[0009] According to the present invention, the cover is fixed to the insulating member by accommodating the projection in the recess and tilting the cover to the other radial side, which simplifies positioning and provides excellent workability. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a perspective view showing a resolver according to an embodiment of the present invention; [Figure 2] FIG. 1 is an exploded perspective view showing a resolver according to an embodiment of the present invention. [Figure 3] FIG. 2 is a perspective view showing a resolver according to an embodiment of the present invention without a cover attached. [Figure 4] 1A is a side view showing a state in which the upper and lower covers are placed on the stator in the embodiment, and FIG. 1B is a cross-sectional view of the placed portion. [Figure 5] FIG. 2 is a partially exploded side view showing the resolver of the embodiment without a cover attached. [Figure 6] FIG. 2 is a cross-sectional view of a resolver according to the embodiment. [Figure 7] FIG. 2 is a plan view showing a state in which a resolver of the embodiment is not attached with a cover. [Figure 8] FIG. 2 is a partially cross-sectional perspective view of a resolver according to the embodiment. [Figure 9] FIG. 2 is a perspective view showing an upper cover in the embodiment. [Figure 10] FIG. 2 is a perspective view of the upper cover in the embodiment as viewed from the back side. [Figure 11] FIG. 2 is a perspective view showing a lower cover in the embodiment. [Figure 12] FIG. 2 is a perspective view of the lower cover in the embodiment as viewed from the back side. DETAILED DESCRIPTION OF THE INVENTION

[0011] 1. Overall structure of the resolver Fig. 1 shows a resolver (angle sensor) 1 according to an embodiment of the present invention. The resolver 1 is a variable reluctance (VR) type resolver. The resolver 1 has a rotor 10 and a stator 100. An upper cover 300 and a lower cover 400 are attached to the stator 100 from both the top and bottom in the axial direction.

[0012] The rotor 10 has a structure in which multiple thin-plate rotor cores are stacked in the axial direction, and is fixed to the output shaft (not shown) of a rotating electrical machine such as a motor. The rotor 10 has a circular opening 11, a non-circular outer periphery, and a key groove 12 that fits with a key formed on the outer periphery of the output shaft. In the following description, the direction of the output shaft will be referred to as the "axial direction," the direction perpendicular to the axial direction will be referred to as the "radial direction," and the direction of rotation around the output shaft will be referred to as the "circumferential direction." Furthermore, the terms "upper" and "lower" will refer to the up and down directions in FIG. 1.

[0013] The thin rotor core that constitutes the rotor 10 is formed by pressing an electromagnetic steel plate into a non-circular shape. Multiple rotor cores are stacked in the axial direction and fixed by crimping at the locations indicated by reference numeral 13 in the figure to form the rotor 10.

[0014] The stator 100 is disposed outside the rotor 10 and is fixed to a housing (not shown) of the rotating electrical machine. A gap is provided between the rotor 10 and the stator 100, allowing the rotor 10 to rotate inside the stator 100.

[0015] The stator 100 includes a stator stack 110. The stator stack 110 has a structure in which multiple thin plate-shaped stator cores are stacked in the axial direction. The stator stack 110 includes an annular core back 111 and multiple teeth 112 that protrude radially inward from the core back 111.

[0016] The stator core is manufactured by pressing electromagnetic steel sheets. A plurality of such stator cores are stacked in the axial direction and fixed by caulking to obtain the stator stack 110.

[0017] Insulators 150 serving as insulating members are fixed to both axial sides of stator stack 110. Insulator 150 is made of insulating resin, and is formed by injection molding upper and lower separate pieces that are then fixed to stator stack 110. Note that insulator 150 may also be injection molded using stator stack 110 as an insert material.

[0018] As shown in Fig. 5, insulator 150 has winding portion 151. Winding portion 151 is formed so as to surround the entire circumference of tooth 112, and includes a tube 152 in the radial center, a flange 153 that extends in the axial and circumferential directions on the radially inner side of tube 152, and protrusions 154 (see Figs. 2 and 3) that protrude upward and downward in the axial direction. A conducting wire is wound around tube 152 between flange 153 and protrusion 154 to form coil 157.

[0019] As shown in Fig. 3, the insulator 150 has an annular protrusion 156 that protrudes upward and downward in the axial direction. A terminal block 200 that is rectangular in plan view and protrudes radially outward is integrally formed on the radially outer side of the annular protrusion 156. A plurality of terminals 210 (six in this example) are embedded in the terminal block 200 by insert molding, and are arranged with gaps between them in a horizontal direction (hereinafter abbreviated as "left direction" or "right direction") that is perpendicular to the radial direction. As shown in Fig. 6, the terminal 210 is L-shaped in side view and includes a pin 211 that protrudes from the upper surface of the terminal block 200 and a plate 212 that extends radially outward from the lower end of the pin 211.

[0020] As shown in Fig. 7, a groove 220 that extends radially and is open to the outside is formed in the terminal block 200. The plate 212 is exposed in the groove 220. Furthermore, as shown in Fig. 6, the groove 220 has a plurality of (six in this example) through-holes 222 that penetrate in the up-down direction.

[0021] A core wire 231 of a lead wire 230 is directly welded to the plate 212. As shown in Fig. 7, a plurality of protrusions 221 that protrude circumferentially and extend axially are formed on the inner surface of the groove 220, and the lead wire 230 is sandwiched between the protrusions 221 on one inner surface and the protrusions 221 on the other inner surface, thereby fixing the lead wire 230. The core wire 231 and the plate 212 are sandwiched between electrodes of a resistance welding machine (not shown) inserted into the groove 220 and the through hole 222, and are melted by passing a current through the electrodes.

[0022] As shown in FIGS. 3 and 4, the terminal block 200 is provided with an engaged portion 250 that engages with an engaging portion of the upper cover 300. The engaged portion 250 has the following configuration. An outer wall 251 that protrudes left or right is formed at the radially outer end of the terminal block 200, and an inner wall (wall) 252 faces the radially inner side of the outer wall 251. An inclined surface 253 that protrudes left or right as it extends axially downward is formed between the outer wall 251 and the inner wall 252. A vertical surface 254 that faces left or right is formed below the inclined surface 253. Furthermore, an inclined surface 252a that protrudes radially outward as it extends axially downward is formed on the surface of the inner wall 252 that faces radially outward.

[0023] As described above, the insulator 150 is formed by injection molding the upper and lower parts separately. As shown in Fig. 4, the lower part of the insulator 150 is also provided with an engaged part 260 that engages with the engaging part of the lower cover 400. The engaged part 260 has a wall 262 that corresponds to the inner wall 252 of the engaged part 250, and an inclined surface 262a that corresponds to the inclined surface 252a. The engaged part 260 also has an inclined surface 263 that corresponds to the inclined surface 253 of the engaged part 250.

[0024] A gate-shaped frame 160 is formed adjacent to the annular protrusion 156 on one side of the insulator 150 opposite the terminal block 200, and the inside of the frame 160 forms a recess 161. This frame 160 is also formed in the same position on the lower part of the insulator 150.

[0025] Next, the upper and lower covers 300, 400 will be described with reference to FIGS. 9 to 12. The upper cover 300 includes a flange 310 having a circular opening 311 in the center, and an outer cylinder 320 and an inner cylinder 330 extending axially downward from the peripheral edge of the flange 310. As shown in FIG. 8, the lower end surface of the outer cylinder 320 contacts the upper end surface of the annular protrusion 156. The inner cylinder 330 is formed in a range excluding, for example, a 120° range around the center of the opening 311. In other words, the inner cylinder 330 has a notch 332 extending over a range of approximately 120°. The notch 332 does not need to be continuous; an area including the notch 332 and a wall like the inner cylinder 330 may be formed alternately. Alternatively, the inner cylinder 330 may be omitted and the entire area may be provided with the notch 332.

[0026] A pair of notches 321 are formed on the center line that bisects the inner tube 330 in a plan view of the outer tube 320, and a hook (convex) 322 that protrudes radially inward in a hook-like shape is formed between the notches 321. Note that reference numeral 323 in the drawing denotes a hole formed by removing a part of the mold that forms the hook 322 when the upper cover 300 is injection molded.

[0027] A terminal block cover 350 is formed on the 180° opposite side of the hook 322. The terminal block cover 350 has the same shape and size as the terminal block 200 in a plan view, and covers the entire terminal block 200. A recess 351 that accommodates the pin 211 of the terminal 210 is formed on the back surface of the terminal block cover 350.

[0028] Arms (engagement portions) 352 that protrude axially downward are formed on both the left and right ends of the terminal block cover 350, and claws (engagement portions) 352a that protrude toward each other with their flat surfaces facing horizontally are formed on the lower ends of the arms 352. This completes the configuration of the engagement portions of the upper cover 300. In addition, on the back surface of the terminal block cover 350, multiple (six in this example) protrusions 353 that protrude axially downward are formed side by side in the left-right direction. The protrusions 353 fit into grooves 220 of the terminal block 200 to press and fix the lead wires 230.

[0029] Next, the lower cover 400 will be described with reference to Figures 11 and 12. The lower cover 400 includes a flange 410 having a circular opening 411 similar to that of the upper cover 300, and an outer cylinder 420 and an inner cylinder 430 extending axially upward from the peripheral edge of the flange 410. As shown in Figure 8, the upper end surface of the outer cylinder 420 contacts the lower end surface of the annular protrusion 156. The inner cylinder 430 also includes a notch 432 formed around the center of the opening 411, for example, excluding a range of 120°. The lower cover 400 also includes a pair of notches 421 and hooks 422 similar to those of the upper cover 300, and an arm (engagement portion) 452 and a hook (engagement portion) 452a.

[0030] The lower cover 400 can also be configured to be fixed with a portion of the terminal block 200 exposed. By exposing a portion of the terminal block 200, it is possible to allow the electrode of a resistance welding machine to access the plate 212 extending radially outward from the lower end of the pin 211 provided on the terminal block 200 when welding the core wire 231 of the lead wire 230 to the plate 212. This allows welding to be performed after the lower cover 400 is attached, improving workability and preventing spatter and the like generated by welding from adhering to the conductors forming the coil 157.

[0031] 2. How to attach the cover As a representative example, a method for attaching the upper cover 300 to the stator 100 will be described. With the terminal block cover 350 of the upper cover 300 lifted and tilted upward, the hook 322 is inserted into the recess 161 of the frame 160 of the insulator 150, and the upper cover 300 is hooked onto the frame 160. From this state, when the upper cover 300 is rotated forward around the hook 322 as the rotation axis, the claw 352a descends in an arc-shaped trajectory. In this case, since the inclined surface 252a is formed on the inner wall 252, the claw 352a reaches the inclined surface 253 without coming into contact with the inner wall 252. Furthermore, since the notch 332 is formed in the inner cylinder 330, contact between the inner cylinder 330 and the insulator 150 is avoided.

[0032] As the claw 352a is further lowered, the claw 352a is pushed by the inclined surface 253, causing the arm 352 to elastically deform leftward or rightward. After the claw 352a passes the inclined surface 253 and reaches the vertical surface 354, the arm 352 elastically returns to its original position, and the claw 352a engages with the lower edge of the vertical surface 254. This fixes the upper cover 300 in the circumferential direction. In this state, the outer peripheral surface of the inner cylinder 330 contacts the inner peripheral surface of the flange 153 of the insulator 150 (see FIG. 6). This prevents the upper cover 300 from moving in either direction relative to the stator 100. Furthermore, the protrusion 353 formed on the terminal block cover 350 abuts against the lead wire 230, fixing the lead wire 230 in the groove 220. The lower cover 400 can also be attached to the stator 100 in the same manner as described above.

[0033] In the resolver 1 of the above embodiment, the upper cover 300 is fixed to the stator 100 simply by inserting the hook 322 into the recess 161 of the insulator frame 160 and rotating the upper cover 300 forward around the hook 322 as a rotation axis, so that the positioning of the hook 322 of the upper cover 300 relative to the stator 100 is simple and the workability is excellent. Furthermore, the hook 322 can be made to have a structure with high rigidity and strength, so that deformation or damage of the hook 322 during assembly can be prevented in advance. The above-mentioned actions and effects also apply to the lower cover 400.

[0034] In particular, in the above embodiment, the arm 352 having the claws 352a is snap-fitted to the engaged portion 250 to fix it in the circumferential direction, so that the upper cover 300 is easily positioned on the terminal block 200 side and is also easily fixed.

[0035] Furthermore, the inner cylinder 330 has a notch 332 on the side of the hook 322, which is the rotation center of the upper cover 300. This prevents the inner cylinder 330 from coming into contact with the insulator 150 when the upper cover 300 is rotated, and since the range of the notch 332 is less than 180°, the inner cylinder 330 comes into contact with the insulator 150 and is fixed in the radial direction. In other words, the inner cylinder 330 of the upper cover 3300 has a portion that faces the insulator 150 in the rotational axis direction with a gap therebetween and a portion that contacts the insulator 150 in the radial direction. Therefore, fixing the upper cover 300 to the stator 100 is easy and easy to do. The above-mentioned actions and effects also apply to the lower cover 400.

[0036] 3. Example of changes The present invention is not limited to the above-described embodiment, but various modifications are possible as follows. i) The range of the notch 332 is appropriately set to a value less than 180° so that contact with the insulator 150 is avoided when the upper cover 300 is rotated, and radial movement of the inner cylinder 330 is prevented by contact with the insulator 150. The same applies to the notch 432.

[0037] ii) In the above embodiment, upper cover 300 is fixed to stator 100 by snap-fitting arms 352 and claws 352a, but arms 352 may be used only for positioning, and fixing may be performed with bolts. For example, through-holes for inserting bolts may be formed in terminal block cover 350, and female threads for screwing the bolts into terminal block 200 may be formed. The same applies to lower cover 400.

[0038] iii) Alternatively, the arms 352 may be omitted and the upper cover 300 may be positioned by inserting the projections 353 formed on the terminal block cover 350 into the grooves 220 .

[0039] iv) In the above embodiment, the recess 161 is formed by the frame 160, but a radially extending elongated hole may be formed on the end face of the insulator 150, and instead of the hook 322, a pin may be formed that extends axially and is inserted into the elongated hole. [Industrial Applicability]

[0040] The present invention can be used in an angle sensor that detects the rotation angle of a rotating electrical machine such as a motor or a generator. [Explanation of symbols]

[0041] 1... resolver (angle sensor), 10... rotor, 11... opening, 12... keyway, 100... stator, 110... stator stack, 111... core back, 112... teeth, 150... insulator, 151... winding portion, 152... cylinder, 153... flange, 154... protrusion, 156... annular protrusion, 157... coil, 160... frame, 161... recess, 200... terminal block, 210... terminal, 211... pin, 212... plate, 220... groove, 221... protrusion, 222... through hole, 230... lead wire, 231... core wire, 250... engaged portion, 251... outer wall, 252... inner wall (wall), 252a... inclination surface, 253...inclined surface, 254...vertical surface, 260...engaged portion, 262...wall, 262a...inclined surface, 263...inclined surface, 300...upper cover, 311...opening, 310...flange, 320...outer tube, 321...notch, 322...hook, 323...hole, 330...inner tube, 332...notch, 350...terminal block cover, 351...recess, 352...arm (engagement portion), 352a...claw, 353...protrusion, 400...lower cover, 411...opening, 410...flange, 420...outer tube, 421...notch, 422...hook, 430...inner tube, 432...notch, 452...arm (engagement portion), 452a...hook (engagement portion).

Claims

1. A rotor, a stator facing the rotor in a radial direction perpendicular to a rotation axis direction of the rotor; an insulating member covering the stator; a conducting wire wound around the insulating member; a cover that covers the conductor, On one side in the radial direction, the outer periphery of the cover has a convex portion, the insulating member has a recess that receives the protrusion and engages with it in the radial direction, The insulating member and the cover are fixed to the other side in the radial direction. Angle sensor.

2. the cover has an engagement portion; the insulating member has an engaged portion corresponding to the engaging portion, the engaging portion and the engaged portion are engaged with each other in a circumferential direction around the rotation axis and fixed to each other; The angle sensor according to claim 1 .

3. the cover includes a plurality of the engagement portions, The plurality of engaging portions face each other in a circumferential direction around the rotation axis. The angle sensor according to claim 2 .

4. the engaging portion includes an arm extending in the direction of the rotation axis and a claw provided at a tip of the arm, The claw engages with the engaged portion. The angle sensor according to claim 3 .

5. On one side in the radial direction, the cover has a portion facing the stator with a gap therebetween in the rotation axis direction; On the other side in the radial direction, the cover has a portion that contacts the stator and the insulating member in the radial direction.

3. The angle sensor according to claim 1 or 2.

6. the cover includes an outer cylinder extending from a peripheral edge of the cover in the direction of the rotation axis, and an inner cylinder extending in the direction of the rotation axis on the radially inner side of the outer cylinder, the inner cylinder being in contact with the insulating member; The angle sensor according to claim 5 .

7. the inner cylinder has a notch in the convex side portion, the notch faces the insulating member across a gap in the rotation axis direction; The angle sensor according to claim 6.

8. the engaged portion includes a wall facing the other side in the radial direction, the wall includes an inclined surface that slopes toward the other side in the radial direction along the rotation axis direction, The wall faces the engaging portion in the radial direction.

3. The angle sensor according to claim 1 or 2.

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