Stator and electric motor

Abstract

A stator according to the present disclosure is provided to an electric motor, and comprises: a coil part that is formed in an annular shape so as to surround a rotor provided to the electric motor and that has a coil end; and a shrinkable tube that covers the coil end without covering the inner circumference of the coil end. A drawn-out wire of the coil part is drawn out from the radially inner side of the coil part.

Description

Stator and motor

[0001] The present disclosure relates to a stator and an electric motor.

[0002] Japanese Patent Laid-Open Publication No. 50-124102 discloses a stator for an electric motor. The stator includes a coil portion having coil ends and multiple protective insulating materials (adhesive tapes). The multiple protective insulating materials are laminated on the surfaces of the coil ends.

[0003] When miniaturizing the electric motor, the configuration shown in Japanese Patent Laid-Open Publication No. 50-124102 is not necessarily preferable.

[0004] A first aspect of the present disclosure is a stator provided in an electric motor, comprising: a coil portion formed in a ring shape to surround a rotor provided in the electric motor and having coil ends; and a shrink tube that covers the coil ends without covering the inner peripheral portions of the coil ends, and wherein lead wires of the coil portion are drawn out from the radially inner side of the coil portion.

[0005] A second aspect of the present disclosure is an electric motor including the stator described above.

[0006] Fig. 1 is an exploded view of an electric motor according to a first embodiment. Fig. 2 is an exploded view showing an accommodating member and a coil bobbin. Fig. 3 is a plan view of a stator. Fig. 4 is a cross-sectional view showing a portion of the stator. Fig. 5 is a plan view of a stator according to a second embodiment. Fig. 6 is a cross-sectional view showing a portion of the stator. Fig. 7 is a plan view of a stator according to a first modified example. Fig. 8 is a cross-sectional view showing a portion of the stator.

[0007] The prior art, including that disclosed in JP 50-124102 A, has at least the following problem. That is, stacking multiple coating members on the surface of the coil end causes the end of the stator in the axial direction to become thicker. From the perspective of miniaturizing electric motors, thickening of the stator is undesirable.

[0008] To accommodate the trend toward smaller motors, one approach being considered is to reduce the amount of conductor wire included in the coil section and make the coil end itself relatively small. This approach is believed to make it possible to make the axial end of the stator relatively small, even when taking into account the increased size. However, reducing the amount of conductor wire included in the coil section poses a problem of reduced motor output.

[0009] Based on the above preliminary explanation, the first embodiment will be described below.

[0010] First Embodiment FIG. 1 is an exploded view of an electric motor 10 according to a first embodiment.

[0011] 1, the electric motor 10 includes a rotating shaft 12, a rotor 14, and a stator 16 (161). An axial direction DA, which is the direction in which the rotating shaft 12 extends, includes a first direction DA1 and a second direction DA2, which is the opposite direction to the first direction DA1.

[0012] The rotating shaft 12 is attached to the rotor 14. The stator 161 is formed in a cylindrical shape so as to surround the rotor 14. The rotor 14 and the rotating shaft 12 are provided inside the stator 161 so as to be rotatable.

[0013] The stator 161 includes a housing member 18, a coil bobbin 20, a coil portion 22, and a pair of shrink tubes 24. The lead wires 26 shown in FIG.

[0014] The housing member 18 is a cylindrical member that can surround the rotor 14. The housing member 18 extends along the axial direction DA. The housing member 18 has end portions 18t (18t1, 18t2) in the axial direction DA. The end portions 18t include a first end portion 18t1 in the first direction DA1 and a second end portion 18t2 in the second direction DA2.

[0015] The housing member 18 (181) may be a magnetic material made of electromagnetic steel or the like, or an insulating material made of resin or the like. In this embodiment, a case where the housing member 181 is a magnetic material will be described. The housing member 181 includes, for example, a plurality of electromagnetic steel plates (not shown) stacked along the axial direction DA, but is not limited to this. An insulating layer 28 is preferably provided on the inside of the housing member 181 (inner wall portion 181i) (see also FIGS. 2 to 4).

[0016] FIG. 2 is an exploded view showing the housing member 181 and the coil bobbin 20. As shown in FIG.

[0017] The coil bobbin 20 is a member that supports the coil portion 22 (see also FIG. 1 ). The coil bobbin 20 has insulating properties. The coil bobbin 20 is provided inside the accommodating member 181. More specifically, the coil bobbin 20 is provided inside the accommodating member 181, which has an insulating layer 28 formed on its inner wall portion 181i. As shown in FIG. 2 , the coil bobbin 20 includes a bobbin core portion 30 and a plurality of partition portions 32.

[0018] The bobbin core 30 is a cylindrical member that extends along the axial direction DA. The rotor 14 and the rotary shaft 12 are provided inside the bobbin core 30.

[0019] The maximum dimension L30 of the bobbin core 30 in the axial direction DA is longer than the dimension L181 of the accommodating member 181 in the axial direction DA (L30 > L181). Therefore, the bobbin core 30 protrudes from the accommodating member 181 (see also FIG. 1 ). More specifically, the bobbin core 30 has a protruding wall portion 34 that protrudes from the accommodating member 181. The protruding wall portion 34 may be formed in an annular (cylindrical) shape around the entire circumference of the bobbin core 30. The protruding wall portion 34 includes a first protruding wall portion 341 in the first direction DA1 and a second protruding wall portion 342 in the second direction DA2. As shown in FIG. 1 , the first protruding wall portion 341 protrudes in the first direction DA1 from the first end portion 18t1 of the accommodating member 181. The second protruding wall portion 342 protrudes in the second direction DA2 from the second end portion 18t2 of the accommodating member 181. It should be noted that one of the first protruding wall portion 341 and the second protruding wall portion 342 may be omitted.

[0020] As shown in Fig. 2, the partition 32 extends along the axial direction DA. The dimension L32 of the partition 32 in the axial direction DA is, but is not limited to, approximately the same as the dimension L181 of the housing member 181 in the axial direction DA (L32 ≈ L181), for example. That is, the error between the dimension L32 and the dimension L181 may be within a predetermined error range. The dimension L32 and the dimension L181 may be equal to each other or may differ within the above-mentioned error range.

[0021] Fig. 3 is a plan view of the stator 161. Fig. 3 shows a plan view of the stator 161 as viewed in the axial direction.

[0022] As shown in FIG. 3 , the multiple partitions 32 (321, 322, ..., 326) protrude from the outer peripheral wall 30p of the bobbin core 30 outward in the radial direction DR of the bobbin core 30 (coil portion 22). When viewed in the axial direction, the multiple partitions 32 are arranged at intervals along the circumferential direction DC of the bobbin core 30 (coil portion 22). For example, the multiple partitions 32 may be arranged point-symmetrically with respect to the center point C of the stator 161 when viewed in the axial direction. The number of partitions 32 that may be provided on the coil bobbin 20 is not limited to six.

[0023] The coil portion 22 has a ring shape when viewed in the axial direction, which can surround the rotor 14 and the rotating shaft 12. The coil portion 22 is formed by a conductor wound around a plurality of partitions 32. An insulating material (not shown) is filled between the wires of the conductor forming the coil portion 22. The insulating material is, for example, a hardened impregnating agent. The impregnating agent is, for example, a thermosetting impregnating agent such as varnish.

[0024] The coil portion 22 has a coil end 36. As described above, the shape of the coil portion 22 when viewed in the axial direction is annular. Therefore, the shape of the coil end 36 when viewed in the axial direction is also annular. The annular coil end 36 has an outer peripheral portion 36p on the outside in the radial direction DR, an inner peripheral portion 36i on the inside in the radial direction DR, and a tip end portion 36t in the axial direction DA (see also FIG. 4 ).

[0025] 4 is a cross-sectional view showing a part of the stator 161. A part of the cross section taken along line IV-IV shown in FIG.

[0026] The coil ends 36 (361, 362) include a first coil end 361 and a second coil end 362. The first coil end 361 protrudes in the first direction DA1 from the first end 18t1 of the accommodating member 181. The second coil end 362 protrudes in the second direction DA2 from the second end 18t2 of the accommodating member 181.

[0027] As shown in FIG. 4, the dimension of the protruding wall portion 34 in the axial direction DA is preferably equal to or greater than the dimension of the portion of the coil end 36 that protrudes from the end portion 18t in the axial direction DA.

[0028] More specifically, dimensions L341 and L361 are shown in FIG. 4 . Dimension L341 is the length from the first end 18t1 of the accommodating member 181 to the tip 341t of the first protruding wall portion 341 in the axial direction DA. Dimension L361 is the length from the first end 18t1 to the tip 36t (361t) of the first coil end 361 in the axial direction DA. Dimension L341 is preferably equal to or greater than dimension L361 (L341≧L361). As shown in FIG. 4 , dimension L341 is more preferably longer than dimension L361 (L341>L361). However, dimension L341 may be shorter than dimension L361.

[0029] FIG. 4 also shows dimensions L342 and L362. Dimension L342 is the axial length DA from the second end 18t2 of the accommodating member 181 to the tip 342t of the second protruding wall portion 342. Dimension L362 is the axial length DA from the second end 18t2 to the tip 36t (362t) of the second coil end 362. Dimension L342 is preferably equal to or greater than dimension L362 (L342≧L362). As shown in FIG. 4, dimension L342 is more preferably longer than dimension L362 (L342>L362). However, dimension L342 may be shorter than dimension L362. Furthermore, the above-described dimensions L341 and L342 may be equal to or different from each other.

[0030] Each of the pair of shrink tubes 24 is formed, for example, from a tubular film material (resin material) that is insulating and heat-shrinkable. The pair of shrink tubes 24 are attached to the coil ends 36 so as to cover the outer peripheries 36p of the coil ends 36 and the tip ends 36t of the coil ends 36 in the axial direction DA. More specifically, the pair of shrink tubes 24 includes a first shrink tube 241 attached to the first coil end 361 and a second shrink tube 242 attached to the second coil end 362.

[0031] The first shrink tube 241 covers the outer circumferential portion 36p (361p) of the first coil end 361. Preferably, the first shrink tube 241 covers the entire outer circumferential portion 361p. Furthermore, the first shrink tube 241 extends from the outer circumferential portion 361p of the first coil end 361 toward the inner circumferential portion 36i (361i) of the first coil end 361, and further covers at least a portion of the tip end 361t of the first coil end 361. Preferably, the first shrink tube 241 covers the entire tip end 361t, but is not limited to this.

[0032] The second shrink tube 242 covers the outer circumferential portion 36p (362p) of the second coil end 362. Preferably, the second shrink tube 242 covers the entire outer circumferential portion 362p. Furthermore, the second shrink tube 242 extends from the outer circumferential portion 362p of the second coil end 362 toward the inner circumferential portion 36i (362i) of the second coil end 362, and further covers at least a portion of the tip end 362t of the second coil end 362. Preferably, the second shrink tube 242 covers the entire tip end 362t, but is not limited to this.

[0033] An inner circumferential portion 36i of the coil end 36 is not covered by the shrink tube 24. The lead wire 26 of the coil portion 22 described above is drawn out from the inner side of the coil portion 22 in the radial direction DR through a gap between the coil portion 22 and the bobbin core 30. More specifically, the lead wire 26 is drawn out from the inner circumferential portion 36i of the coil end 36 through a gap between the coil portion 22 and the bobbin core 30. The lead wire 26 is part of the conductor that forms the coil portion 22. The coil portion 22 can be connected to a power source (not shown) via the lead wire 26 to supply current to the coil portion 22.

[0034] According to this embodiment, the stator 161 and the electric motor 10 including the stator 161 can achieve the effects described below, for example.

[0035] The outer circumferential portion 36p and the tip end 36t (at least a portion of the tip end 36t) of the coil end 36 are covered by the shrink tube 24. Compared to the inner circumferential portion 36i, the outer circumferential portion 36p and the tip end 36t are more likely to come into contact with, for example, the housing member 181 containing electromagnetic steel or external foreign matter (dust, water, oil, etc.). Covering the outer circumferential portion 36p and the tip end 36t with the shrink tube 24 effectively prevents contact between the coil end 36 and the housing member 181, foreign matter, etc. If the entire outer circumferential portion 36p is covered with the shrink tube 24, contact between the outer circumferential portion 36p and foreign matter, etc. can be more effectively prevented. If the entire tip end 36t is covered with the shrink tube 24, contact between the tip end 36t and foreign matter, etc. can be more effectively prevented.

[0036] The shrunk shrink tube 24 can effectively secure the coil end 36. Therefore, the shrink tube 24 can prevent the shape of the coil end 36 from being distorted due to, for example, the weight of the coil end 36. By preventing the shape of the coil end 36 from being distorted, for example, contact between the coil end 36 and the housing member 181 can be more effectively prevented.

[0037] [Correction Based on Rule 91 06.09.2024] According to this embodiment, the coil ends 36 can be well protected by a shrink tube 24 having a minimum thickness. That is, if the coil ends 36 are covered with adhesive tape, for example, there is a risk that the adhesive tape will peel off from the coil ends 36 when the coil ends 36 to which the adhesive tape is attached are heated during the manufacturing process of the stator 16. Therefore, adhesive tape alone does not necessarily provide good protection for the coil ends 36. Furthermore, if cloth is wrapped around the coil ends 36 to prevent the adhesive tape from peeling off from the coil ends 36, the adhesive tape, cloth, etc. attached to the coil ends 36 will cause the ends of the stator 16 to expand. As a result, this may hinder the miniaturization of the stator 16 while suppressing a reduction in the amount of conductor wire included in the coil portion 22, and may also hinder the miniaturization of the electric motor 10 equipped with the stator 16 while suppressing a decrease in output power of the electric motor 10. In this regard, according to the present embodiment, the shrink tube 24 covering the coil ends 36 can maintain tight contact with the coil ends 36 even when heated. Therefore, even a shrink tube 24 with a minimum thickness can adequately protect the coil ends 36. Because the coil ends 36 can be protected by the shrink tube 24, which is a relatively thin member, it is possible to suppress enlargement of the stator 161 without reducing the amount of conductor wire included in the coil portion 22. In other words, the stator 161 according to the present embodiment is suitable for miniaturizing the electric motor 10 while suppressing a decrease in output of the electric motor 10.

[0038] The shrink tube 24 does not cover the inner periphery 36i of the coil end 36, and the lead wire 26 is drawn out from the inner side in the radial direction DR (inner periphery 36i) of the coil portion 22. This can reduce the risk of interference between the shrink tube 24 and the lead wire 26.

[0039] The lead wire 26 is drawn out from the inner side in the radial direction DR (inner peripheral portion 36i) of the coil portion 22. Therefore, for example, it is not necessary to provide a hole in the shrink tube 24 to allow the lead wire 26 to be drawn out from the outer peripheral portion 36p of the coil end 36. This allows the shrink tube 24 to reliably cover the entire outer peripheral portion 36p.

[0040] The bobbin core 30 is provided with a protruding wall 34 interposed between the coil end 36 (coil portion 22) and the rotating shaft 12, rotor 14, etc. The protruding wall 34 includes at least one of a first protruding wall 341 protruding in a first direction DA1 from the accommodating member 181 and a second protruding wall 342 protruding in a second direction DA2 from the accommodating member 181. This reduces the risk of contact between the coil end 36 (coil portion 22) and the rotating shaft 12, rotor 14, etc. The dimension in the axial direction DA of the protruding wall 34 provided on the bobbin core 30 is preferably equal to or greater than the dimension in the axial direction DA of the portion of the coil end 36 protruding from the end 18t of the accommodating member 181 (L341≧L361; L342≧L362). As a result, the bobbin core 30, including the protruding wall 34, blocks the coil 22 from the rotating shaft 12, the rotor 14, etc. Note that the dimension L341 of the first protruding wall 341 and the dimension L342 of the second protruding wall 342 may be equal to or different from each other. In other words, the stator 161 allows, to some extent, appropriate design changes to the dimensions L341 and L342 depending on the convenience of the manufacturer of the stator 161.

[0041] It is more preferable that the dimension in the axial direction DA of the protruding wall portion 34 provided on the bobbin core 30 is longer than the dimension in the axial direction DA of the portion of the coil end 36 that protrudes from the end portion 18t of the housing member 181 (L341 > L361; L342 > L362). This further reduces the risk of contact between the coil end 36 (coil portion 22) and the rotating shaft 12, rotor 14, etc.

[0042] The protruding wall portion 34 is formed around the entire circumference of the bobbin core portion 30. This more reliably blocks the coil portion 22 from the rotating shaft 12, the rotor 14, etc. by the bobbin core portion 30, including the protruding wall portion 34. This further reduces the risk of contact between the coil end 36 (coil portion 22) and the rotating shaft 12, the rotor 14, etc.

[0043] The housing member 181 is made of electromagnetic steel. This makes it possible to suppress iron loss occurring in the electric motor 10. Furthermore, the housing member 181 made of electromagnetic steel can be made of a material commonly used for stator cores (such as electromagnetic steel sheet). This makes it possible to suppress increases in the procurement costs of the material for the housing member 181, for example.

[0044] An insulating layer 28 is formed on the inner wall 181i of the housing member 181, which is made of an alloy (electromagnetic steel). This can prevent a short circuit between the housing member 181 and the coil portion 22. If the housing member 181 is made of an insulator such as resin, a short circuit between the housing member 181 and the coil portion 22 can be prevented without the insulating layer 28.

[0045] The shrink tube 24 has heat shrinkability. Therefore, the shrink tube 24 easily shrinks when heated. In this case, for example, a pressing member to prevent the adhesive tape attached to the coil end from lifting up is not necessary. Therefore, the manufacturing method of the stator 161 is simpler than the prior art disclosed in, for example, Japanese Patent Laid-Open Publication No. 50-124102.

[0046] The electric motor 10 including the stator 161 can be realized in a relatively small size while suppressing a decrease in output.

[0047] Second Embodiment A second embodiment will be described below. In the second embodiment, descriptions that overlap with those of the first embodiment will be omitted as appropriate. In addition, in the drawings used in the second embodiment, the same reference numerals are used for the same components as those described in the first embodiment.

[0048] Fig. 5 is a plan view of the stator 16 (162) according to the second embodiment. Fig. 5 shows a plan view of the stator 162 as viewed in the axial direction. Fig. 6 is a cross-sectional view showing a portion of the stator 162. Fig. 6 shows a portion of the cross section taken along line VI-VI shown in Fig. 5.

[0049] The stator 162 includes a housing member 18 (182), a coil portion 22, and a shrink tube 24. The housing member 182 has a cylindrical shape. The rotating shaft 12 and the rotor 14 of the electric motor 10 can be provided inside the housing member 182.

[0050] The housing member 182 is a stator core (magnetic body) including electromagnetic steel, etc. The housing member 182 includes, for example, but is not limited to, a plurality of electromagnetic steel plates (not shown) stacked along the axial direction DA.

[0051] The housing member 182 has a teeth portion 38. The teeth portion 38 includes a plurality of teeth 40. Although six teeth 40 are shown in FIG. 5 , the number of teeth 40 is not limited to this. The plurality of teeth 40 are arranged to surround the rotor 14 when viewed in the axial direction. For example, the plurality of teeth 40 can be arranged point-symmetrically with respect to the center point C of the stator 162 when viewed in the axial direction.

[0052] Slots 42 are formed between adjacent teeth 40 in the circumferential direction DC of the housing member 182 (coil portion 22). In other words, the housing member 182 has a plurality of slots 42 formed by the tooth portions 38. Although not shown in the figure, an insulating layer is provided on the surface of the slots 42.

[0053] The coil portion 22 is formed by a conductor wound around a plurality of teeth 40. As shown in Fig. 6, a portion of the coil portion 22 (conductor) is located within a plurality of slots 42. An insulating material (not shown) is filled between the wires that form the coil portion 22. The insulating material is, for example, a hardened impregnating agent.

[0054] 6, the coil ends 36 of the coil portion 22 protrude from the accommodating member 182 along the axial direction DA. The coil ends 36 include a first coil end 361 in the first direction DA1 and a second coil end 362 in the second direction DA2.

[0055] The stator 162 is provided with a pair of shrink tubes 24 including a first shrink tube 241 and a second shrink tube 242. The first shrink tube 241 covers an outer circumferential portion 361p of the first coil end 361 and a tip end 361t of the first coil end 361 in the first direction DA1. The second shrink tube 242 covers an outer circumferential portion 362p of the second coil end 362 and a tip end 362t of the second coil end 362 in the second direction DA2. Each of the pair of shrink tubes 24 has, for example, insulating properties and heat-shrinkability.

[0056] An inner circumferential portion 36i of the coil end 36 is not covered by the shrink tube 24. The lead wire 26 of the coil portion 22 is drawn out from the inner side (inner circumferential portion 36i) of the coil portion 22 in the radial direction DR.

[0057] The stator 162 can be included in the electric motor 10 (see also FIG. 1). The stator 162 and the electric motor 10 including the stator 162 can achieve the effects described below, for example.

[0058] The outer circumferential portion 36p and the tip end 36t (at least a portion of the tip end 36t) of the coil end 36 are covered by the shrink tube 24. This effectively prevents contact between the coil end 36 and the housing member 182, foreign matter, etc., as in the first embodiment. When the entire outer circumferential portion 36p is covered by the shrink tube 24, contact between the outer circumferential portion 36p and foreign matter, etc. is more effectively prevented. When the entire tip end 36t is covered by the shrink tube 24, contact between the tip end 36t and foreign matter, etc. is more effectively prevented. Furthermore, the shrunk shrink tube 24 can effectively secure the coil end 36. Furthermore, because the coil end 36 can be protected by the shrink tube 24, which is a relatively thin member, it is possible to suppress enlargement of the stator 162 without reducing the amount of conductor wire included in the coil portion 22.

[0059] The shrink tube 24 does not cover the inner periphery 36i of the coil end 36, and the lead wire 26 is drawn out from the inner side (inner periphery 36i) of the coil portion 22 in the radial direction DR. This makes it possible to prevent interference between the shrink tube 24 and the lead wire 26, as in the first embodiment. Furthermore, there is no need to provide a hole in the shrink tube 24 to allow the lead wire 26 to be drawn out from the outer periphery 36p of the coil end 36. Therefore, the entire outer periphery 36p can be reliably covered by the shrink tube 24.

[0060] The housing member 182 is a cylindrical stator core containing an alloy such as electromagnetic steel. This makes it possible to suppress iron loss occurring in the electric motor 10. Furthermore, the housing member 182, which is made of electromagnetic steel, can be made of a material commonly used for stator cores (such as electromagnetic steel sheet). This makes it possible to suppress increases in the procurement costs of the material for the housing member 182, for example.

[0061] The housing member (stator core) 182 includes teeth 38. The coils 22 are provided on the teeth 38. In this case, the coil bobbin 20 (see the first embodiment) is not required.

[0062] An insulating layer (not shown) is provided on the surface of the slot 42. This can reduce the risk of short-circuiting between the coil portion 22 and the housing member 182.

[0063] The shrink tube 24 has heat shrinkability. Therefore, the shrink tube 24 easily shrinks when heated, for example. In this case, for example, a pressing member for preventing the adhesive tape attached to the coil end from lifting up is not required. Therefore, the manufacturing method of the stator 162 is simpler than the prior art disclosed in, for example, Japanese Patent Laid-Open Publication No. 50-124102.

[0064] The electric motor 10 including the stator 162 can be realized in a relatively small size while suppressing a decrease in output.

[0065] The above-described embodiments may be modified as follows. In the following modifications, descriptions that overlap with the embodiments will be omitted as appropriate. In addition, in the drawings used for the following modifications, the same reference numerals are used for the same components as those described in the embodiments.

[0066] (Modification 1) Fig. 7 is a plan view of a stator 16 (16A) according to Modification 1. Fig. 7 shows a plan view of the stator 16A as viewed in the axial direction. Fig. 8 is a cross-sectional view showing a portion of the stator 16A. Fig. 8 shows a portion of the cross section taken along line VIII-VIII shown in Fig. 7.

[0067] With respect to the first embodiment, the protruding wall portion 34 of the coil bobbin 20 may be formed only on a portion of the bobbin core portion 30 in the circumferential direction DC. This reduces the amount of material consumed by the coil bobbin 20. For example, FIGS. 7 and 8 show a bobbin core portion 30 (bobbin core portion 30A) having a protruding wall portion 34 (protruding wall portion 34A) according to this modification. The protruding wall portion 34A protrudes in the axial direction DA from a portion of the bobbin core portion 30A in the circumferential direction DC. More specifically, the protruding wall portion 34A shown in FIGS. 7 and 8 protrudes in the first direction DA1 from a portion of the bobbin core portion 30A located between the partition portions 322 and 323 in the circumferential direction DC.

[0068] In this case, the lead wires 26 are preferably drawn out at a location corresponding to the protruding wall portion 34. That is, the coil portion 22 has a lead portion 44, which is a portion from which the lead wires 26 are drawn out. The position of the lead portion 44 in the circumferential direction DC preferably corresponds to the position of the protruding wall portion 34A in the circumferential direction DC. For example, as shown in FIG. 7 , the lead portion 44 is included in a portion of the coil portion 22 that is located between the partition portion 322 and the partition portion 323 in the circumferential direction DC. In this manner, the positions of the lead portion 44 and the protruding wall portion 34A preferably overlap in the circumferential direction DC. By overlapping the positions of the lead portion 44 and the protruding wall portion 34A in the circumferential direction DC, the risk of contact between the lead wires 26 and the rotating shaft 12, the rotor 14, etc. can be reduced.

[0069] (Variation 2) Although not specifically illustrated, the coil unit 22 may include a plurality of coils, for example, a coil for use as a U-phase coil, a coil for use as a V-phase coil, and a coil for use as a W-phase coil.

[0070] When multiple coils are included in the coil section 22, the coil end 36 can be formed by the multiple coils. In other words, the multiple coils included in the coil section 22 can collectively form a single annular first coil end 361. Furthermore, the multiple coils included in the coil section 22 can collectively form a single annular second coil end 362. As a result, only two shrink tubes 24 are required for the stator 16, regardless of the number of coils included in the coil section 22.

[0071] Furthermore, the coil section 22 including multiple coils may have multiple lead wires 26 corresponding to the number of coils. For example, the coil section 22 may have a lead wire 26 drawn from the U-phase coil, a lead wire 26 drawn from the V-phase coil, and a lead wire 26 drawn from the W-phase coil.

[0072] In relation to the first modification, the coil bobbin 20 may have a plurality of protruding wall portions 34A corresponding to a plurality of lead wires 26 (a plurality of lead portions 44). For example, the lead portions 44 of the U-phase coil, the lead portions 44 of the V-phase coil, and the lead portions 44 of the W-phase coil may differ from one another in the circumferential direction DC of the bobbin core portion 30A. In this case, the coil bobbin 20 may have a protruding wall portion 34A corresponding to the lead portions 44 of the U-phase coil, a protruding wall portion 34A corresponding to the lead portions 44 of the V-phase coil, and a protruding wall portion 34A corresponding to the lead portions 44 of the W-phase coil.

[0073] When the coil portion 22 has multiple lead-out portions 44, the positions of the multiple lead-out portions 44 and the position of one protruding wall portion 34A may overlap in the circumferential direction DC. That is, the multiple lead-out wires 26 may be led out from portions of the coil portion 22 that correspond to the same protruding wall portion 34A. For example, the multiple lead-out wires 26 may be led out from a position in the coil portion 22 between the partition portion 322 and the partition portion 323 in the circumferential direction DC (see also FIG. 7 ). In this case, not only is the risk of contact between the multiple lead-out wires 26 and the rotating shaft 12, the rotor 14, etc. reduced, but the number of protruding wall portions 34A can be minimized (one).

[0074] (Variation 3) As described above, the inner wall portion 181i of the housing member 181 is provided with the insulating layer 28. Also, as described above, an insulating material (not shown) is filled between the wires of the conductors forming the coil portion 22. The insulating material and the insulating layer 28 may be made of the same material (impregnating agent). This can prevent an increase in the number of materials.

[0075] (Variation 4) As described above, the coil portion 22, the rotor 14, etc. are provided in the space inside the cylindrical accommodating member 18. In light of this, the electric motor 10 may further include a housing (not shown) that covers the space inside the accommodating member 18, as necessary. This makes it possible to prevent foreign matter present outside the electric motor 10 from entering the inside of the accommodating member 18. The foreign matter is not limited to, but may be, for example, dust, water, oil, etc.

[0076] For example, the electric motor 10 may be provided with a housing that can cover the entire stator 16. Furthermore, for example, as described above, the accommodating member 18 has a first end 18t1 and a second end 18t2 (see also FIGS. 1 and 6 ). The electric motor 10 may be provided with a first housing attached to the first end 18t1 and a second housing attached to the second end 18t2. In this case, the first housing and the second housing sandwich the accommodating member 18 in the axial direction DA. At least one of the first housing and the second housing may be provided with one or more holes through which the rotating shaft 12, the lead wires 26, etc. are inserted.

[0077] (Variation 5) The shape of the housing member 18 or the bobbin core 30 is not limited to a cylinder and may be a square tube. Furthermore, the shape of the coil portion 22 (coil end 36) as viewed in the axial direction is not limited to a ring and may have, for example, corners.

[0078] (Combination of Multiple Modifications) The multiple modifications described above may be combined as appropriate within a range that does not contradict each other.

[0079] According to the above embodiment and modified example, the stator 16 is suitable for miniaturizing the electric motor 10 while suppressing a decrease in the output of the electric motor 10 .

[0080] The following additional notes are further disclosed regarding the above embodiment.

[0081] (Supplementary Note 1) A stator (16) according to the present disclosure is a stator provided in an electric motor (10), and includes a coil portion (22) formed in an annular shape so as to surround a rotor (14) provided in the electric motor and having coil ends (36), and a shrink tube (24) that covers the coil ends without covering inner peripheries (36i) of the coil ends, and lead wires (26) of the coil portion are drawn out from the inside of the coil portion in the radial direction (DR).

[0082] (Appendix 2) The stator described in Appendix 1 may include a coil bobbin (20) that supports the coil portion, the coil bobbin including a cylindrical bobbin core (30) extending along an axial direction (DA) and a plurality of partition portions (32) that protrude radially outward from the bobbin core, the coil portion being formed by a conductor wound around the plurality of partition portions, and the maximum dimension (L30) of the bobbin core in the axial direction being longer than the dimension (L32) of the partition portions in the axial direction.

[0083] (Appendix 3) The stator described in Appendix 2 may further include a cylindrical housing member (181) extending along the axial direction to surround the coil bobbin, the coil ends protruding from an end (18t) of the housing member in the axial direction, and the bobbin core portion having a protruding wall portion (34) protruding from the end.

[0084] (Appendix 4) The stator may be the one described in Appendix 3, wherein the protruding wall portion has a first protruding wall portion (341) protruding from the accommodating member toward a first direction (DA1) that is one side in the axial direction, and a second protruding wall portion (342) protruding from the accommodating member toward a second direction (DA2) that is the other side in the axial direction, and the dimension (L341) of the first protruding wall portion in the axial direction is different from the dimension (L342) of the second protruding wall portion in the axial direction.

[0085] (Appendix 5) The stator may be the one described in Appendix 3, wherein the protruding wall portion has a first protruding wall portion (341) protruding from the accommodating member toward a first direction (DA1) that is one side in the axial direction, the coil portion has a first coil end (361) that is the coil end formed at an end of the coil portion in the first direction, and the dimension (L341) of the first protruding wall portion in the axial direction is equal to or greater than the dimension (L361) of the portion of the first coil end that protrudes from the accommodating member in the axial direction.

[0086] (Appendix 6) The stator may be the one described in Appendix 5, wherein the protruding wall portion has a second protruding wall portion (342) protruding from the accommodating member toward a second direction (DA2) that is the other side in the axial direction, the coil portion has a second coil end (362) that is the coil end formed at an end of the coil portion in the second direction, and the dimension (L342) of the second protruding wall portion in the axial direction is equal to or greater than the dimension (L362) of the portion of the second coil end that protrudes from the accommodating member in the axial direction.

[0087] (Supplementary Note 7) The stator according to Supplementary Note 3 may be a stator in which the protruding wall portion is formed around the entire circumference of the bobbin core portion on at least one side in the axial direction of the bobbin core portion.

[0088] (Appendix 8) The stator may be the one described in Appendix 3, wherein, on at least one side of the bobbin core in the axial direction, the protruding wall portion is formed on a part of the bobbin core when viewed in the axial direction, and the lead wire is drawn out at a position corresponding to the protruding wall portion.

[0089] (Supplementary Note 9) The stator according to Supplementary Note 8 may be a stator in which the coil portion has a plurality of the lead wires, and the plurality of lead wires are led out at positions corresponding to the same protruding wall portion.

[0090] (Supplementary Note 10) The stator according to any one of Supplementary Notes 3 to 9, wherein the housing member is formed of electromagnetic steel.

[0091] (Supplementary Note 11) The stator according to Supplementary Note 10 may further include an insulating layer (28) formed on the inner wall portion (181i) of the housing member.

[0092] (Supplementary Note 12) The stator according to any one of Supplementary Notes 3 to 9, wherein the housing member is formed of resin.

[0093] (Supplementary Note 13) The stator according to Supplementary Note 1 may further include a cylindrical stator core (182) having teeth (38), and the coil portion may be formed by a conductor wound around the teeth.

[0094] (Supplementary Note 14) The stator according to any one of Supplementary Notes 1 to 13 may be a stator in which the shrinkable tube is a heat-shrinkable tube.

[0095] (Supplementary Note 15) An electric motor (10) according to the present disclosure is an electric motor including the stator according to any one of Supplementary Notes 1 to 14.

[0096] Although the present disclosure has been described in detail, the present disclosure is not limited to the individual embodiments described above. Various additions, substitutions, modifications, partial deletions, etc. are possible in these embodiments without departing from the gist of the present disclosure or the spirit of the present disclosure derived from the content of the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each operation and the order of each process are shown as examples and are not limited to these. The same applies when numerical values ​​or mathematical expressions are used in the description of the above-described embodiments.

[0097] 10...Motor 14...Rotor 16, 161, 162, 16A...Stator 18, 181, 182...Accommodating member 18t...End portion 20...Coil bobbin 22...Coil portion 24...Shrinkage tube 26...Lead wire 28...Insulating layer 30, 30A...Bobbin core portion 32, 321 to 326...Partition portion 34, 34A...Protruding wall portion 36...Coil end 36i...Inner peripheral portion 38...Teeth portion 44...Lead portion 181i...Inner wall portion 341...First protruding wall portion 342...Second protruding wall portion 361...First coil end 362...Second coil end L30...Maximum dimension L32, L341, L342, L361, L362...Dimensions

Claims

1. A stator provided for an electric motor, A coil portion is formed in an annular shape to surround the rotor of the electric motor and has coil ends, A heat-shrinkable tube that covers the coil end without covering the inner circumference of the coil end, Equipped with, A stator from which the lead wires of the coil portion are drawn out from the radially inner side of the coil portion.

2. A stator according to claim 1, The coil section is supported by a coil bobbin, The aforementioned coil bobbin is A cylindrical bobbin core extending along the axial direction, Multiple partitions protruding radially outward from the bobbin core, Equipped with, The coil portion is formed by the wires wound around the multiple partition portions. A stator in which the maximum dimension of the bobbin core in the axial direction is longer than the dimension of the partition in the axial direction.

3. A stator according to claim 2, The coil bobbin is further provided with a cylindrical housing member that extends along the axial direction so as to surround the coil bobbin, The coil end protrudes from the axial end of the housing member, The bobbin core portion is a stator having a protruding wall portion that protrudes from the end portion.

4. A stator according to claim 3, The aforementioned protruding wall portion is A first protruding wall portion that protrudes from the housing member in a first direction which is one of the axial directions, A second protruding wall portion that protrudes from the housing member in a second direction which is the other direction in the axial direction, It has, A stator in which the axial dimensions of the first protruding wall portion and the axial dimensions of the second protruding wall portion are different.

5. A stator according to claim 3, The protruding wall portion has a first protruding wall portion that protrudes from the housing member in a first direction which is one of the axial directions, The coil portion has a first coil end which is the coil end formed at the end of the coil portion in the first direction, A stator in which the axial dimension of the first protruding wall portion is greater than or equal to the axial dimension of the portion of the first coil end that protrudes from the housing member.

6. A stator according to claim 5, The aforementioned protruding wall portion has a second protruding wall portion that protrudes from the housing member in a second direction which is the other direction in the axial direction, The coil portion has a second coil end which is the coil end formed at the end of the coil portion in the second direction, A stator in which the axial dimension of the second protruding wall portion is greater than or equal to the axial dimension of the portion of the second coil end that protrudes from the housing member.

7. A stator according to claim 3, A stator in which the protruding wall portion is formed around the entire circumference of the bobbin core portion, on at least one side of the bobbin core portion in the axial direction.

8. A stator according to claim 3, On at least one side of the bobbin core in the axial direction, the protruding wall is formed on a part of the bobbin core in an axial view. The aforementioned leader wire is a stator that is drawn out at the portion corresponding to the protruding wall portion.

9. A stator according to claim 8, The coil section has a plurality of the aforementioned lead wires, A stator in which multiple leader lines are drawn out from portions corresponding to the same protruding wall portion.

10. A stator according to any one of claims 3 to 9, The aforementioned housing member is a stator formed of electromagnetic steel.

11. A stator according to claim 10, A stator further comprising an insulating layer formed on the inner wall of the aforementioned housing member.

12. A stator according to any one of claims 3 to 9, The aforementioned housing member is a stator formed of resin.

13. A stator according to claim 1, It further comprises a cylindrical stator core having teeth, A stator in which the coil portion is formed by a conductor wound around the teeth portion.

14. A stator according to any one of claims 1 to 8, 13, The aforementioned heat-shrinkable tube is a stator.

15. An electric motor comprising a stator according to any one of claims 1 to 8 or 13.