stator

Abstract

A stator (10) comprises: a first outer casing member (20) surrounding an outer peripheral portion (14a) of a coil end portion (14) on both ends (12a, 12b) of an iron core portion (12); a second outer casing member (22) connected to the first outer casing member (20) and surrounding an axial end portion (14c) of the coil end portion (14); and a mold member (18) covering the coil end portion (14) and in contact with the first outer casing member (20) and the second outer casing member (22), wherein a hole (24) is formed in the second outer casing member (22) on the one end (12a) side, and a surface of the mold member (18) side of the second outer casing member (22) on the one end (12a) side is inclined in a manner that the thickness continuously becomes thinner toward the hole (24).

Description

Technical Field

[0001] The present invention relates to a stator having reduced gaps in molded components. Background Art

[0002] Japanese Patent Application Laid-Open No. 2014-050185 discloses a technique of filling a molded resin (molded member) in a space formed by a housing 1 and an end member 7. A stator having a structure in which a molded member is filled in a coil is also called a "molded stator". Summary of the invention

[0003] From the perspective of the quality of the stator, in order to suppress the occurrence of unexpected abnormalities such as corona discharge, it is ideal that the molded component filled in the coil does not contain bubbles. Bubbles are also called "voids". However, in the molded stator of Japanese Patent Publication No. 2014-050185, since the end member 7 is a plane, when the molded component is filled in the entire space, air is enclosed in the corners of the above space. Therefore, in the structure of Japanese Patent Publication No. 2014-050185, the situation of voids during manufacturing cannot be suppressed.

[0004] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a stator having reduced gaps in molded components.

[0005] One embodiment of the invention is a stator of an electric motor, comprising: an iron core portion; a coil, which is arranged on the iron core portion in a manner that a coil end portion is provided at each end side of the iron core portion in the axial direction of the electric motor; a first outer casing member, which is arranged on each end side of the two end sides in a manner that surrounds the outer peripheral side of the coil end portion; a second outer casing member, which is connected to the first outer casing member on each end side of the two end sides and is arranged in a manner that surrounds the end side of the coil end portion in the axial direction; and a molded member, which covers the coil end portion on each end side of the two end sides and is in contact with the first outer casing member and the second outer casing member, a hole penetrating the second outer casing member is formed in the second outer casing member on one end side of the two ends, and a surface of the second outer casing member on the molded member side of the one end side is inclined in a manner that the thickness of the second outer casing member on the one end side continuously becomes thinner toward the hole.

[0006] According to the present invention, there is provided a stator having a reduced gap of a molded member.

[0007] The above objects, features and advantages will be easily understood from the following description of the embodiments described with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1A It is a cross-sectional view of a stator according to an embodiment.

[0009] Figure 1B It is a top view of the stator.

[0010] Figure 2 This is a top view of the stator of Modification Example 1.

[0011] Figure 3 This is a cross-sectional view of a stator according to Modification Example 2. DETAILED DESCRIPTION

[0012] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings by listing preferred embodiments. In addition, the directions described below follow the arrows shown in the accompanying drawings.

[0013] [Implementation Method]

[0014] Figure 1A It is a cross-sectional view of the stator 10 according to the embodiment. Figure 1B is a top view of the stator 10. In addition, Figure 1A yes Figure 1B IA-IA line cross-sectional diagram.

[0015] The stator 10 of this embodiment is one of the components that constitute the motor together with the rotor and the shaft. The stator 10 includes: a core portion 12; a coil 16, the coil 16 being provided on the core portion 12 in a manner that the coil end 14 is provided on each of the two ends 12a and 12b of the core portion 12 in the axial direction (up and down direction) of the motor; and a molded member 18 covering the coil end 14. The above-mentioned "axial direction" refers to the direction along the length direction of the axis that is the main axis of rotation of the motor.

[0016] In the present embodiment, the core portion 12 is cylindrical with an axial hole X that penetrates the core portion 12 in the axial direction. A rotor and a shaft are disposed in the motor in the axial hole X. The shape of the core portion 12 is not limited to a cylindrical shape as long as it is cylindrical.

[0017] The coil 16 is made of a conductive wire. The conductive wire is, for example, an enameled wire. The coil end 14 of the coil 16 has an outer peripheral portion 14a, an inner peripheral portion 14b, and an axial end 14c.

[0018] In the motor having the stator 10 of the present embodiment, when the rotor of the motor generates torque, current flows in the coil 16. When the current flows, heat is generated in the coil 16. The heat is absorbed by the mold member 18 covering the coil end 14.

[0019] The molded member 18 in this embodiment is a member containing epoxy resin in the material. The molded member 18 not only covers the outer peripheral portion 14a, the inner peripheral portion 14b and the end portion 14c of the coil end 14 on the surface, but also fills between the different phases of the wire material forming the coil end 14. In this way, in this embodiment, since the contact area between the coil end 14 and the molded member 18 is fully ensured, the heat of the coil 16 can be effectively absorbed by the molded member 18.

[0020] In addition, an insulating material such as epoxy resin is contained in the molded member 18. Therefore, even if a conductive object (such as metal) exists around the coil 16 and the molded member 18, it is possible to prevent the conductive object from accidentally contacting and short-circuiting the coil 16. As a result, the reliability of the motor having the stator 10 of the present embodiment is improved.

[0021] In addition, the material of the molded member 18 is not limited to the above-mentioned materials. For example, the material of the molded member 18 may contain a resin other than epoxy resin. Alternatively, the molded member 18 may contain a filler in addition to the resin. The filler is, for example, bauxite (aluminum oxide). By containing bauxite, the thermal conductivity of the molded member 18 is improved.

[0022] The stator 10 further includes a first outer casing member 20 and a second outer casing member 22, which are provided on each of the two ends 12a, 12b so as to surround the coil end 14. Figure 1A As shown, the first exterior member 20 is a member that is in contact with the core portion 12 and is provided to surround the coil end portion 14 and the mold member 18 from the outer peripheral portion 14a side. In the present embodiment, the first exterior member 20 is made of an alloy containing aluminum.

[0023] like Figure 1A As shown in FIG. 1 , the second outer casing member 22 is a member provided in a manner of surrounding the coil end 14 and the molded member 18 from the coil end 14c side. The first outer casing member 20 and the second outer casing member 22 may be configured as a single member connected to each other in an integral manner, or may be configured as separate members. In this embodiment, as shown in FIG. Figure 1AAs shown, the case where the first outer casing member 20 and the second outer casing member 22 are connected as a whole is described. The shape of the second outer casing member 22 is annular with an outer casing axial hole Y that penetrates the second outer casing member 22 in the axial direction, so as not to hinder the configuration of the rotor and the shaft in the axial hole X of the core portion 12. The second outer casing member 22 is made of an alloy containing aluminum in the present embodiment, similarly to the first outer casing member 20. In the following, for the purpose of distinction, the second outer casing member 22 on the side of one end 12a (upper side) of the two ends 12a, 12b is sometimes referred to as "second outer casing member 22A", and the second outer casing member 22 on the side of the other end 12b (lower side) is referred to as "second outer casing member 22B".

[0024] The second outer casing 22A is provided with a hole 24 that penetrates the second outer casing 22A in the axial direction at a position above the core portion 12 and different from the outer casing shaft hole Y. The surface of the second outer casing 22A on the molding member 18 side is inclined so that the thickness of the second outer casing 22A gradually decreases toward the hole 24. Figure 1B As shown, the hole 24 is arched when viewed from the upper side, and at least two holes are formed. In addition, the shape of the hole 24 when viewed from the upper side is not limited to Figure 1B , can also be changed appropriately.

[0025] like Figure 1A As shown, the first outer casing 20 and the second outer casing 22 are closely attached to the molded member 18 covering the coil end 14. Thus, the first outer casing 20 and the second outer casing 22 absorb the heat of the molded member 18. In addition, the first outer casing 20 and the second outer casing 22 release the absorbed heat to the outside air. In this way, in this embodiment, the heat of the coil 16 is discharged to the outside of the stator 10.

[0026] As is well known, the thermal conductivity of aluminum is equal to or greater than that of epoxy resin. Therefore, the first exterior member 20 and the second exterior member 22 can effectively absorb the heat of the mold member 18.

[0027] In addition, the material of the first outer package member 20 and the second outer package member 22 does not necessarily need to contain aluminum. In addition, in the present embodiment, the material of the first outer package member 20 and the second outer package member 22 is set to an alloy, but in the case of using metal as the material, for example, the first outer package member 20 and the second outer package member 22 may also be composed of a single metal instead of an alloy. However, from the above-mentioned point of view of heat conduction, the material of the first outer package member 20 and the second outer package member 22 is preferably a material having a thermal conductivity at least greater than that of the molded member 18. In addition, the first outer package member 20 and the second outer package member 22 are connected to the coil end portion 14 as shown in FIG. Figure 1A The illustrated indirect contact is ideal for the quality of the stator 10 , but direct contact is also possible.

[0028] The above is the overall structure of the stator 10 of the present embodiment. The stator 10 reduces the gaps in the molded member 18. Therefore, the motor having the stator 10 suppresses the possibility of unexpected abnormalities such as corona discharge to a minimum and has good reliability.

[0029] [Modifications]

[0030] The above embodiment is described as an example of the present invention, but it is obvious that various changes or improvements can be made to the above embodiment. According to the description of the claims, the form with such changes or improvements can also be included in the technical scope of the present invention.

[0031] (Variant 1)

[0032] Figure 2 It is a top view of the stator 10 according to the first modification.

[0033] In the embodiment, it is described that the number of holes 24 is not limited to 2. This modification is a specific example. Figure 2 As shown, three holes 24 may be formed in the second outer casing member 22A. Figure 2 For example, four or more holes 24 may be formed in the second exterior member 22A.

[0034] (Variant 2)

[0035] Figure 3 It is a cross-sectional view of the stator 10 according to the second modification.

[0036] The second outer casing member 22A may also be formed by stacking a plurality of members. Figure 3 As shown, the second exterior member 22A may include an inner member 26 in contact with the mold member 18 and an outer member 28 stacked on the inner member 26 on the side opposite to the mold member 18. In this case, the hole 24 formed in the second exterior member 22A communicates the inner member 26 and the outer member 28.

[0037] In this modification, as long as the surface of the inner member 26 on the mold member 18 side is inclined so that the thickness of the inner member 26 becomes thinner toward the hole 24, the surface of the outer member 28 does not need to be inclined. In addition, if the outer member 28 is connected to the first exterior member 20, the inner member 26 does not need to be connected to the first exterior member 20. In addition, this modification is not limited to Figure 3 For example, the second exterior member 22A may include another member stacked together with the inner member 26 and the outer member 28 .

[0038] (Variant 3)

[0039] The above-described embodiment and various modifications may be appropriately combined within a range where no contradiction occurs.

[0040] [Inventions Obtained from Embodiments]

[0041] Hereinafter, the invention that can be understood from the above-mentioned embodiment and modified examples will be described.

[0042] A stator (10) of an electric motor, characterized in that it comprises: an iron core portion (12); a coil (16) provided on the iron core portion (12) in a manner that the coil end portion (14) is provided on each of the two ends (12a, 12b) of the iron core portion (12) in the axial direction of the electric motor; a first outer casing (20) provided on each of the two ends (12a, 12b) in a manner that the outer circumference (14a) of the coil end portion (14) is surrounded; and a second outer casing (22) connected to the first outer casing (20) in a manner that the outer circumference (14a) of the coil end portion (14) is surrounded on each of the two ends (12a, 12b) The invention relates to a molding member (18) which covers the coil end (14) on each side of the two ends (12a, 12b) and contacts the first outer casing member (20) and the second outer casing member (22), wherein a hole (24) penetrating the second outer casing member (22) is formed on the second outer casing member (22) on the side of one end (12a) of the two ends (12a, 12b), and the surface of the molding member (18) on the side of the second outer casing member (22) on the side of the one end (12a) is inclined in a manner that the thickness of the second outer casing member (22) on the side of the one end (12a) becomes thinner continuously toward the hole (24).

[0043] Thus, a stator (10) having a reduced gap in a molded component (18) is provided.

[0044] The thermal conductivity of the first outer casing (20) and the second outer casing (22) may be greater than the thermal conductivity of the molded member (18). Thus, the first outer casing (20) and the second outer casing (22) can effectively absorb the heat of the molded member (18).

[0045] The material of the mold member (18) may also contain an insulating resin, thereby preventing a short circuit caused by an unintentional contact between the coil (16) and the outside.

Claims

1. A stator of an electric motor, characterized in that: include: Iron core; a coil provided on the core portion in a manner having a coil end portion on each of both end sides of the core portion in the axial direction of the motor; a first exterior member provided on each of the two end sides so as to surround the outer peripheral side of the coil end; a second exterior member connected to the first exterior member on each of the two end sides and provided so as to surround an end side of the coil end in the axial direction; and a mold member covering the coil end portion on each of the two end sides and in contact with the first exterior member and the second exterior member, A hole penetrating the second outer casing member is formed on the second outer casing member at one end of the two ends, and the hole is in an arch shape when viewed from the axial direction of the stator. A surface of the second exterior member on the one end side on the mold member side is inclined so that a thickness of the second exterior member on the one end side continuously becomes thinner toward the hole.

2. The stator according to claim 1, characterized in that: The thermal conductivity of the first exterior member and the second exterior member is equal to or greater than the thermal conductivity of the mold member.

3. The stator according to claim 1 or 2, characterized in that: The material of the molding member includes an insulating resin.

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