Molded motor manufacturing method and molded motor

Abstract

A molded motor production method provided with a step in which a stator having a stator core and a coil wound around the stator core and an inside metal member positioned so as to cover the outside of the stator are positioned in a mold, and a step in which a molded resin is formed by injecting liquid resin into the interior of the mold through a gate (resin injection part) provided to the mold and hardening the liquid resin, wherein the resin injection part is positioned in the radial direction of the molded resin after molding.

Description

[Technical field]

[0001] The present disclosure relates to a manufacturing method for a molded motor and a molded motor. [Background technology]

[0002] Conventionally, a molded motor in which a stator is covered with a molded resin is known (see Patent Document 1). The molded motor includes, for example, a stator having a stator core and a coil wound around the stator core, a rotor disposed inside the stator, and a molded resin that covers the stator.

[0003] In recent years, the heat generated by the coils in the stator has increased with the increase in the power output of molded motors. This has led to a problem of thermal degradation of the molding resin that covers the stator. In order to suppress the thermal degradation of the molding resin, it has been proposed to use an epoxy resin containing a filler with high thermal conductivity as the molding resin (see Patent Document 2).

[0004] However, if an excessive current flows through the stator coil and the coil becomes abnormally heated, the insulator that covers the surface of the conductor that forms the core of the coil may melt, causing a rare short circuit in which the conductors of the coil wound around the stator core short circuit each other. When this rare short circuit occurs, sparks may occur.

[0005] If the coil breaks due to abnormal heating at this time, current will stop flowing through the coil and no further problems will occur. However, in high-power molded motors, the wire diameter of the stator coil is made thicker (for example, φ0.3 mm or more), making the coil less likely to break even if it heats up abnormally. For this reason, in high-power molded motors, there is a high possibility of a layer short circuit occurring and sparks occurring.

[0006] On the other hand, when the temperature inside the molded motor rises due to heat generation from the coil, flammable gases may be generated from resin parts such as insulators that are interposed between the stator core and the coil.

[0007] When flammable gas is present inside a molded motor in this manner, if a layer short occurs and a spark is generated, the spark may ignite the gas and cause a fire.

[0008] In particular, if flammable gas is generated near the lead bush, air (oxygen) will flow into the vicinity of the lead bush, making it easier for sparks to occur between the lead wires inserted into the lead bush, increasing the risk of fire.

[0009] If the lead bush is made of a resin material, the lead bush will melt due to the fire. If the lead bush melts in this way, there is a risk that the fire will leak from the melted part of the lead bush to the outside of the molded motor and spread.

[0010] In addition, the fire does not only leak out from the vicinity of the lead bush, but also from other parts of the molded resin. For example, if the molded resin is thermally deteriorated due to heat generation from the coil, causing cracks in the molded resin, the fire may leak out from the cracked parts of the molded resin to the outside of the molded motor, causing the fire to spread.

[0011] Therefore, in order to prevent the spread of fire caused by heat generation from the coil wound around the stator, a technique has been proposed in which the outside of the stator is covered with a metal member over the entire circumference of the stator.

[0012] Fig. 10 is a half cross-sectional view of a molded motor of a comparative example. For example, as shown in Fig. 10, in a molded motor including a stator 10 having a stator core 11 and a coil 12, a rotor 20 having a rotating shaft 21, a rotor core 22 and a permanent magnet 23, and a molded resin 30X, it is possible to provide an inner metal member 40 as a metallic inner cover inside the molded resin 30X.

[0013] 10 is configured in an annular cylindrical shape having a step portion on the outer surface, and is disposed between the molded resin 30X and the stator 10. Specifically, the annular cylindrical inner metal member 40 covers the outside of the stator 10 over the entire circumference, and has a first portion 41 which is a large diameter portion facing the coil end 12a of the coil 12 wound around the stator core 11, and a second portion 42 which is a small diameter portion facing the stator core 11 and has an outer diameter smaller than that of the first portion 41.

[0014] However, if the inner metal member 40 is provided to cover the outside of the stator 10, holes will form in the molded resin 30X located radially outward of the inner metal member 40, which may reduce the strength of the molded resin 30X located radially outward of the inner metal member 40.

[0015] In particular, when an inner metal member 40 having a first portion 41 with a larger outer diameter than a second portion 42 is disposed between the molded resin 30X and the stator 10, the gap between the outer surface of the inner metal member 40 and the inner surface of the mold becomes narrow in the portion corresponding to the first portion 41 with the larger outer diameter, so that the molded resin 30X in this portion is prone to develop holes and a thin portion is generated in the molded resin 30X in this portion. As a result, the strength of the molded resin 30X is further reduced. [Prior art documents] [Patent documents]

[0016] [Patent Document 1] International Publication No. 2012 / 101976 [Patent Document 2] JP 2004-143368 A Summary of the Invention

[0017] The present disclosure has been made to solve such problems, and aims to provide a molded motor manufacturing method and a molded motor that can suppress a decrease in strength of the molded resin, even when an inner metal member is arranged to cover the outside of the stator.

[0018] In order to achieve the above-mentioned objective, one aspect of a manufacturing method for a molded motor according to the present disclosure includes a step of placing a stator having a stator core and a coil wound around the stator core, and an inner metal member arranged to cover the outside of the stator, in a mold, and a step of forming a molded resin by injecting liquid resin into the interior of the mold through a resin injection portion provided in the mold and hardening the liquid resin, wherein the resin injection portion is positioned in the radial direction of the molded resin after molding.

[0019] Furthermore, the molded resin after molding may have a protrusion that protrudes outward in a radial direction perpendicular to the axial direction of the rotating shaft of the molded motor, and the resin injection portion may be provided in a portion corresponding to the protrusion.

[0020] It is also preferable that, during the injection of the liquid resin, the stator is pressed down vertically from the upper side to the lower side by a pin.

[0021] The inner metal member may also include a first portion located outside the stator in the radial direction, and a second portion located outside the stator and a distance to the rotating shaft that is shorter than the distance from the first portion to the rotating shaft.

[0022] It is also preferable that the coil includes a coil end protruding from the stator core in a direction along the axial center, the first portion facing the coil end, and the second portion facing the stator core.

[0023] One aspect of a molded motor according to the present disclosure comprises a stator having a stator core and a coil wound around the stator core, a rotor arranged opposite the stator and having a rotating shaft extending in an axial direction, a molded resin covering the stator, and an inner metal member having a portion located between the molded resin and the stator, the inner metal member including a first portion located outside the stator in a radial direction perpendicular to the axial direction, and a second portion located outside the stator in the radial direction and whose distance to the rotating shaft is shorter than the distance from the first portion to the rotating shaft, wherein the molded resin is formed by hardening of liquid resin injected from the radial direction.

[0024] Furthermore, a gate mark formed when the liquid resin is injected to mold the molding resin may be present at a lateral portion of the molding resin in the radial direction.

[0025] The molding resin may further have a protruding portion protruding outward in the radial direction, and the molding resin may be formed by hardening the liquid resin injected from the protruding portion.

[0026] Furthermore, a gate mark left when the liquid resin is injected to mold the molding resin may be present on the protruding portion.

[0027] The molded resin may further include a bracket fixed to the molded resin, the bracket having a first side wall portion covering a side surface of the molded resin, and an outer surface of the molded resin may be flush with the outer surface of the first side wall portion of the bracket or may be located more inward than the outer surface of the first side wall portion, at least in a portion corresponding to the first portion.

[0028] Furthermore, the molded resin may further include an outer metal member having a cover portion covering an outer surface located on the axial side of the molded resin and a second side wall portion covering a portion of the outer surface located on the radial side of the molded resin, and at least a portion of the outer surface located on the radial side of the molded resin that is not covered by the second side wall portion may be flush with the outer surface of the second side wall portion of the outer metal member or may be located more inward than the outer surface of the second side wall portion.

[0029] Moreover, it is preferable that the thickness of the molding resin at the portion corresponding to the first portion is 1 mm or more.

[0030] The molding resin may be made of an unsaturated polyester resin.

[0031] According to the present disclosure, even if the inner metal member is arranged so as to cover the outside of the stator, a decrease in strength of the molding resin can be suppressed. [Brief description of the drawings]

[0032] [Figure 1] FIG. 1 is a perspective view of a molded motor according to an embodiment. [Diagram 2] FIG. 2 is an exploded perspective view of the molded motor according to the embodiment. [Diagram 3] FIG. 3 is a half cross-sectional view of a molded motor according to an embodiment. [Figure 4] FIG. 4 is a cross-sectional view of the molded motor according to the embodiment taken along line IV-IV in FIG. [Diagram 5] FIG. 5 is a top view of the molded motor according to the embodiment. [Figure 6] FIG. 6 is a perspective view of an inner metal member in the molded motor according to the embodiment. [Figure 7] FIG. 7 is a diagram illustrating a step of arranging the stator and the inner metal member in the manufacturing method of the molded motor according to the embodiment. [Figure 8A]FIG. 8A is a diagram illustrating a step of injecting liquid resin into a mold in a manufacturing method for a molded motor according to an embodiment. [Figure 8B] FIG. 8B is a view for explaining a step of injecting liquid resin into a mold in the method for manufacturing a molded motor according to the embodiment. [Figure 8C] FIG. 8C is a view for illustrating a step of injecting liquid resin into a mold in the method for manufacturing a molded motor according to an embodiment. [Figure 9] FIG. 9 is a flowchart illustrating a method for manufacturing a molded motor according to an embodiment. [Figure 10] FIG. 10 is a half cross-sectional view of a molded motor of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] Hereinafter, embodiments of the present disclosure will be described. Note that each of the embodiments described below shows a specific example of the present disclosure. Therefore, the numerical values, components, the arrangement and connection of the components, the steps, and the order of the steps shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Therefore, among the components in the following embodiments, components that are not described in the independent claims showing the highest concept of the present disclosure will be described as optional components.

[0034] In addition, each drawing is a schematic diagram and is not necessarily a precise illustration. In each drawing, the same reference numerals are used for substantially the same configurations, and duplicated explanations are omitted or simplified.

[0035] (Embodiment) The configuration of the molded motor 1 according to the embodiment will be described with reference to Figs. 1 to 5. Fig. 1 is a perspective view of the molded motor 1 according to the embodiment. Fig. 2 is an exploded perspective view of the molded motor 1. Fig. 3 is a half cross-sectional view of the molded motor 1. Fig. 4 is a cross-sectional view of the molded motor 1 taken along line IV-IV in Fig. 3. Fig. 5 is a top view of the molded motor 1. In Figs. 2 to 4, the direction in which the rotating shaft 21 of the molded motor 1 extends is defined as the axial direction X. In a plane perpendicular to the axial direction X, the direction extending from the axis C of the rotating shaft 21 is defined as the radial direction Y. The direction going around the axis C is defined as the circumferential direction Z. The axial direction X is the direction of the axis C of the rotating shaft 21 (axial direction). In other words, the axial direction X is the longitudinal direction of the rotating shaft 21. The radial direction Y is a direction perpendicular to the direction of the axis C of the rotating shaft 21. In this specification, the axial direction X is a first direction, and the radial direction Y is a second direction perpendicular to the first direction.

[0036] As shown in Figures 1 to 5, the molded motor 1 includes a stator 10, a rotor 20 arranged opposite the stator 10, a molded resin 30 covering the stator 10, and an inner metal member 40 having a portion located between the molded resin 30 and the stator 10.

[0037] The molded motor 1 further includes a first bearing 51 and a second bearing 52, a first bracket 61 and a second bracket 62, an outer metal member 70, a circuit board 80, and a lead bush 90.

[0038] In the molded motor 1, the mold resin 30, the first bracket 61, the second bracket 62, and the outer metal member 70 form the outer shell of the molded motor 1.

[0039] The molded motor 1 in this embodiment is a brushless motor that does not use brushes. The molded motor 1 is an inner rotor type motor in which the rotor 20 is disposed inside the stator 10.

[0040] 3 and 4, the stator 10 is disposed so as to surround the rotor 20 with a small air gap between the rotor 20 and the stator 10. The stator 10 includes a stator core 11, a coil 12, and an insulator 13.

[0041] Stator core 11 is an annular iron core that generates a magnetic force for rotating rotor 20. As shown in Fig. 3, stator core 11 is, for example, a laminated body in which a plurality of electromagnetic steel sheets are laminated in the longitudinal direction (axial direction X) of rotating shaft 21 of rotor 20. Note that stator core 11 is not limited to a laminated body, and may be a bulk body made of a magnetic material.

[0042] 4, the stator core 11 has a yoke 11a formed in an annular shape so as to surround the rotor 20, and a plurality of teeth 11b protruding in a convex shape from the yoke 11a toward the rotating shaft 21. The stator core 11 is provided with twelve teeth 11b.

[0043] The yoke 11a is a back yoke formed on the outer side of each of the teeth 11b. The yoke 11a is formed in an annular shape with the axis C as its center.

[0044] The teeth 11b are arranged at equal intervals in the circumferential direction Z while forming slots 14 between adjacent teeth. In addition, an extension portion 11b1 is formed at the extended tip of each tooth 11b, extending to both sides in the circumferential direction Z. The inner circumferential surface located at the tip of the tooth 11b, including the extension portion 11b1, becomes a magnetic pole surface facing the outer circumferential surface of the rotor 20. Note that, between two adjacent teeth 11b, there is a gap (slot opening) between the extension portion 11b1 of one tooth 11b and the extension portion 11b1 of the other tooth 11b. Note that, in this embodiment, the stator core 11 is provided with 12 teeth 11b. The number of slots 14 is 12. That is, the number of slots in the molded motor 1 is 12.

[0045] The coil 12 is wound around the stator core 11. The coil 12 is a winding coil wound around the stator core 11 via an insulator 13. Specifically, as shown in Fig. 4, the coil 12 is wound around each of a plurality of teeth 11b of the stator core 11.

[0046] 3, each coil 12 has a coil end 12a protruding from the stator core 11 in the axial direction X (first direction) of the rotating shaft 21. In other words, the coil end 12a is a portion of the coil 12 wound around the teeth 11b of the stator core 11 that protrudes from the stator core 11 (teeth 11b) in the axial direction X. The coil ends 12a protrude from the stator core 11 on both sides in the axial direction X of the rotating shaft 21. Therefore, each tooth 11b has a coil end 12a (first coil end) located on the output shaft 21a side and a coil end 12a (second coil end) located on the opposite side to the output shaft 21a side.

[0047] The molded motor 1 is a high-power motor with an output of 750 W or more. For this reason, a wire diameter φ of 0.3 mm or more is used for the coil 12. As an example, the wire diameter φ of the coil 12 is 0.5 mm to 1.0 mm.

[0048] The coils 12 are each made up of a unit coil for each of three phases, namely, U-phase, V-phase, and W-phase, which are electrically out of phase with each other by 120 degrees. That is, the coils 12 wound around the teeth 11b are driven by three-phase AC that is supplied to each of the U-phase, V-phase, and W-phase units. The coils 12 of each phase are connected to each other by a jumper wire (not shown). The jumper wire is disposed on the outer peripheral wall portion of the insulator 13. The coils 12 and the jumper wire are, for example, an insulating coated wire composed of a conductor wire forming a core wire and an insulator that insulates the surface of the conductor wire.

[0049] The ends of the coils 12 of each phase are connected by a winding connection part of the circuit board 80. Specifically, the circuit board 80 is formed with pattern wiring for electrically connecting the coils 12 for each of the U-phase, V-phase, and W-phase, and the ends of the coils 12 of each phase are electrically connected to the pattern wiring of the circuit board 80 by solder or the like. The circuit board 80 has an opening in the center through which the rotating shaft 21 passes, and is, for example, annular (donut-shaped), sector-shaped (arc-shaped), C-shaped, or the like.

[0050] Alternatively, the terminals of the coils 12 of each phase may be configured to use a circuit board or a connecting member made of a conductive material. Note that the present disclosure is applicable to any motor, regardless of the motor specifications, as long as the motor has a structure in which lead wires are inserted inside the motor housing.

[0051] The insulator 13 is an insulating frame that covers the stator core 11. Specifically, the insulator 13 covers the teeth 11b of the stator core 11 and is provided for each tooth 11b. The insulator 13 is made of an insulating resin material such as polybutylene terephthalate (PBT).

[0052] The rotor 20 rotates due to the magnetic force generated in the stator 10. As shown in Fig. 2 to Fig. 4, the rotor 20 has a rotating shaft 21 extending in the direction of an axis C, and rotates about the axis C of the rotating shaft 21. The rotating shaft 21 extends along the axial direction X.

[0053] The rotor 20 has a configuration in which N poles and S poles are repeatedly arranged in the circumferential direction Z. The rotor 20 is an interior permanent magnet rotor (IPM rotor), and has a rotor core (rotor core) 22 and permanent magnets 23 inserted into a plurality of magnet insertion holes 22a formed in the rotor core 22.

[0054] As shown in Fig. 3, rotor core 22 is a substantially cylindrical laminate in which a plurality of electromagnetic steel sheets are laminated along axial direction X of rotating shaft 21. Also, as shown in Fig. 4, rotor core 22 is formed with a plurality of magnet insertion holes 22a penetrating in axial direction X at equal intervals in circumferential direction Z. One permanent magnet 23 is inserted into each magnet insertion hole 22a. In this embodiment, there are ten magnetic poles, and the ten permanent magnets 23 are arranged such that south poles and north poles are alternately positioned in circumferential direction Z.

[0055] A rotating shaft 21 is fixed to the center of the rotor core 22. The rotating shaft 21 is, for example, a shaft such as a metal bar, and passes through the rotor core 22 so as to extend to both sides of the rotor core 22. The rotating shaft 21 is fixed to the rotor core 22 by, for example, press-fitting into the center hole of the rotor core 22 or shrink-fitting.

[0056] As shown in Fig. 3, the rotating shaft 21 is held by a first bearing 51 and a second bearing 52. This allows the rotor 20 to rotate relative to the stator 10. As an example, the first bearing 51 and the second bearing 52 are bearings that rotatably support the rotating shaft 21. The rotating shaft 21 passes through the first bearing 51, and although not shown, a load such as a rotating fan is attached to a portion of the rotating shaft 21 that protrudes to the outside from the first bearing 51. The portion of the rotating shaft 21 to which a load such as a rotating fan is attached is also referred to as an output shaft 21a.

[0057] The rotor 20 thus configured rotates due to the magnetic flux generated in the stator 10. Specifically, when power is supplied from the circuit board 80 to the coil 12 of the stator 10, a field current flows through the coil 12, generating magnetic flux in the stator core 11. A magnetic force generated by the interaction between the magnetic flux generated in the stator core 11 and the magnetic flux generated from the permanent magnets 23 of the rotor 20 becomes a torque that rotates the rotor 20, and the rotor 20 rotates.

[0058] 3, the stator 10 is covered with molded resin 30. The molded resin 30 covers the outer portion of the stator 10 over the entire circumference in the circumferential direction Z of the stator 10. Specifically, the molded resin 30 covers the outer portions of the stator core 11, the coils 12, and the insulators 13. The molded resin 30 contacts the outer surfaces of the coils 12 and the insulators 13.

[0059] The molded resin 30 further covers the inner metal member 40. Specifically, the molded resin 30 covers the outer portion of the inner metal member 40 over the entire circumference of the inner metal member 40 in the circumferential direction Z. The molded resin 30 contacts the entire outer surface of the inner metal member 40.

[0060] The stator 10 and the inner metal member 40 are fixed to the molded resin 30. The stator 10 and the inner metal member 40 are integrated together with the molded resin 30.

[0061] The molded resin 30 is made of an insulating resin material having excellent thermal conductivity, such as polyester resin or epoxy resin. The molded resin 30 is made of a thermosetting resin. In this embodiment, the molded resin 30 is made of unsaturated polyester, which is a thermosetting resin. Specifically, the molded resin 30 is made of white BMC (Bulk Molding Compound) unsaturated polyester resin.

[0062] The molded resin 30 constitutes a case that is part of the outer shell of the molded motor 1. In other words, the molded resin 30 that covers the stator 10 constitutes a housing that contains the rotor 20.

[0063] As shown in Figs. 1 to 5, molded resin 30 has a main body 31 forming the trunk of molded motor 1, and protrusions 32 provided on main body 31. A plurality of protrusions 32 are provided on main body 31. Specifically, as shown in Fig. 5, four protrusions 32 are provided at equal intervals in the circumferential direction Z. Note that main body 31 and protrusions 32 are integrated by molding to form one molded resin 30.

[0064] 3, the main body 31 covers the stator 10. Specifically, the main body 31 covers the stator core 11, the coils 12, the insulator 13, and the inner metal member 40. The main body 31 is a cylindrical body having a first opening 31a located at one end in the axial direction X and a second opening 31b located at the other end in the axial direction X.

[0065] The protruding portion 32 protrudes outward in the radial direction Y. Specifically, the protruding portion 32 protrudes from the outer surface of the main body portion 31. The protruding portion 32 protrudes outward from the side surface of the main body portion 31 along the radial direction Y. The protruding portion 32 is a leg portion of the molded motor 1. The protruding portion 32 functions as an attachment portion for attaching the molded motor 1 to an external device or the like. The protruding portion 32 is provided with a through hole for inserting a screw or the like.

[0066] As shown in FIG. 2 and FIG. 3, a step portion 30a is formed on the outer surface of the molded resin 30 over the entire circumference in the circumferential direction Z. The step portion 30a is formed on the main body portion 31. Therefore, the main body portion 31 has a large diameter portion with a large outer diameter and a small diameter portion with a smaller outer diameter than the large diameter portion, with the step portion 30a as a boundary. That is, in the main body portion 31, the outer surface of the large diameter portion is located outward from the outer surface of the small diameter portion. The large diameter portion of the main body portion 31 is located on the opposite side to the output shaft 21a side, and the small diameter portion of the main body portion 31 is located on the output shaft 21a side. The step width of the step portion 30a is, for example, about a few tenths of a millimeter. As an example, the step width of the step portion 30a is 1 mm or less, for example, 0.5 mm.

[0067] 1 and 5, the molded resin 30 formed by molding has a gate mark 30G. The gate mark 30G is formed at a connection between the gate and the resin molded product (molded resin 30) when liquid resin is injected into a metal mold to mold the molded resin 30. The gate mark 30G is formed at a lateral portion of the molded resin 30 in the radial direction Y. In other words, the molded resin 30 is formed by hardening the liquid resin injected from the radial direction Y.

[0068] Gate marks 30G, which are created when liquid resin is injected to mold the molding resin 30, are present in the protruding portions 32. That is, the molding resin 30 is formed by hardening the liquid resin injected from the protruding portions 32. More specifically, the gate marks 30G are present at the base portions of the protruding portions 32. As shown in FIG. 5, one gate mark 30G is present in each of the multiple protruding portions 32.

[0069] Incidentally, the gate mark 30G may remain even if the surface of the molded resin 30 is polished. However, the surface of the molded resin 30 may be polished so that no gate mark 30G remains. Even if the gate mark 30G becomes difficult to see by polishing the surface of the molded resin 30, the path through which the liquid resin was injected can be confirmed by checking the components contained in the liquid resin when forming the molded resin 30, such as the density or orientation of the filler.

[0070] 3, a first bracket 61 is provided at one end of the molded resin 30 in the axial direction X. A second bracket 62 is provided at the other end of the molded resin 30 in the axial direction X. The first bracket 61 holds a first bearing 51. The first bearing 51 is fixed to a recess of the first bracket 61. The second bracket 62 holds a second bearing 52. The second bearing 52 is fixed to the second bracket 62.

[0071] The first bracket 61 is disposed so as to cover the first opening 31a of the main body 31. The second bracket 62 is disposed so as to cover the second opening 31b of the main body 31. The first bracket 61 has a lid 61a that covers the first opening 31a of the main body 31 and a first side wall 61b that covers the side of the molded resin 30. The lid 61a of the first bracket 61 is a bottom surface portion that covers the bottom surface of the molded resin 30. The lid 61a covers the entire outer surface located on the axis C direction side of the molded resin 30. The first side wall 61b of the first bracket 61 covers a part of the bottom side of the outer surface located on the radial direction Y side of the molded resin 30. The first side wall 61b is provided around the entire side surface of the molded resin 30.

[0072] On the other hand, the second bracket 62 has a lid portion that closes the second opening 31b of the main body portion 31. However, it does not cover the side surface of the molded resin 30, and does not have a portion corresponding to the first side wall portion 61b of the first bracket 61. Therefore, the overall outer diameter of the second bracket 62 is smaller than the overall outer diameter of the first bracket 61. In other words, the outer size of the first bracket 61 is larger than that of the second bracket 62.

[0073] The first bracket 61 and the second bracket 62 are made of, for example, a metal material such as iron. For example, the first bracket 61 and the second bracket 62 are made of a metal plate with a constant thickness. The first bracket 61 and the second bracket 62 are fixed to the molded resin 30. Specifically, the second bracket 62 is fixed to the molded resin 30 together with the stator 10 when the stator 10 is molded with resin. On the other hand, the first bracket 61 is fixed to the molded resin 30 after molding.

[0074] As shown in Figs. 1 to 4, a lead bush 90 is attached to the molded resin 30. The lead bush 90 is a cylindrical member. As shown in Fig. 3, an electric wire 81 connected to a circuit board 80 is inserted into the lead bush 90. The lead bush 90 functions as an extraction section for extracting the electric wire 81 to the outside, and also functions as a protection section for protecting the electric wire 81. The lead bush 90 is attached to the molded resin 30 by being inserted into an opening formed in a part of the outer wall section of the molded resin 30. The lead bush 90 is made of a resin material such as PBT or a non-metallic material such as ceramic.

[0075] Electric power is supplied to the electric wire 81 for energizing the coil 12 wound around the stator 10. That is, electric power is supplied to the circuit board 80 via the electric wire 81. The electric wire 81 is a power supply line, for example a lead wire. The electric wire 81 is composed of three lead wires. As described above, electric power is supplied to the electric wire 81 for energizing the coil 12 directly or indirectly. In addition, a signal for controlling the molded motor 1 may be supplied to the electric wire 81 from a control device external to the molded motor 1.

[0076] 3, the inner metal member 40 fixed to the molded resin 30 is a metal inner cover (first metal cover) that is disposed inside the molded resin 30. Specifically, at least a portion of the inner metal member 40 is disposed between the molded resin 30 and the stator 10. In the present embodiment, the entire inner metal member 40 is disposed between the molded resin 30 and the stator 10.

[0077] The inner metal member 40 is made of a metal plate with a constant thickness. The thickness of the inner metal member 40 is, for example, several mm or less. In this embodiment, the inner metal member 40 is made of a zinc-plated steel plate with a thickness of 0.5 mm. However, the material and thickness of the inner metal member 40 are not limited to this.

[0078] Here, the structure of the inner metal member 40 will be described with reference to Fig. 3 and Fig. 6. Fig. 6 is a perspective view of the inner metal member 40 in the molded motor 1 according to the embodiment.

[0079] As shown in FIG. 6, the inner metal member 40 is a cylindrical body with both sides open and shaped like an annular cylinder having a step portion 40a on the outer surface. The step width of the step portion 40a is, for example, about a few tenths of a millimeter. As an example, the step width of the step portion 40a is 1 mm or less, for example, 0.5 mm. As shown in FIG. 3 and FIG. 6, the inner metal member 40 has a first portion 41 of an annular cylinder, which is a large diameter portion having a larger outer diameter, and a second portion 42 of an annular cylinder having an outer diameter smaller than that of the first portion 41, with the step portion 40a as a boundary. That is, as shown in FIG. 3, the first portion 41, which is a large diameter portion, is located outside the stator 10 in the radial direction Y and is also farther from the second portion 42 to the rotating shaft 21 than the second portion 42, and is located outside the second portion 42. In other words, the second portion 42, which is a small diameter portion, is located outside the stator 10 in the radial direction Y, and the distance to the rotating shaft 21 is shorter than the distance from the first portion 41 to the rotating shaft 21, and is located inside the first portion 41.

[0080] The annular cylindrical inner metal member 40 surrounds the stator 10 from the outside over the entire circumference in the circumferential direction Z. That is, a first portion 41 and a second portion 42 of the inner metal member 40 are located outside the stator 10. The inner metal member 40 as a whole surrounds the coil end 12a, the insulator 13, and the stator core 11, which are located on the side opposite to the output shaft 21a.

[0081] Specifically, the first portion 41 of the inner metal member 40 is located radially outward of the coil end 12a located on the opposite side to the output shaft 21a. In other words, the first portion 41 faces the coil end 12a located on the opposite side to the output shaft 21a. The first portion 41 is disposed spaced apart from the coil end 12a located on the opposite side to the output shaft 21a.

[0082] The second portion 42 of the inner metal member 40 is located outside the stator core 11 in the radial direction Y. That is, the second portion 42 faces the stator core 11. The second portion 42 is in contact with a side surface of the stator core 11. Note that the length of the second portion 42 in the axial direction X is longer than the length of the first portion 41 in the axial direction X, but is not limited to this.

[0083] 1 and 3, an outer metal member 70 is also fixed to the molded resin 30. The outer metal member 70 is a metal outer cover (second metal cover) that is disposed on the outside of the molded resin 30. Specifically, the outer metal member 70 covers the outer surface of the molded resin 30. The outer metal member 70 is attached to the second bracket 62 side (output shaft 21a side) of the molded resin 30.

[0084] The outer metal member 70 surrounds the coil end 12a and the insulator 13 located on the output shaft 21a side. The outer metal member 70 is cup-shaped with an opening at the center. The outer metal member 70 has a disk-shaped lid portion 71 with an opening and a ring-shaped second side wall portion 72 standing on the outer peripheral end of the lid portion. The lid portion 71 of the outer metal member 70 is a top surface portion that covers the top surface of the molded resin 30. The lid portion 71 covers the entire outer surface located on the axis C direction side of the molded resin 30. The second side wall portion 72 of the outer metal member 70 covers a part of the top surface side of the outer surface located on the radial direction Y side of the molded resin 30. The second side wall portion 72 is cylindrical and is provided around the entire side surface of the molded resin 30. A part of the second bracket 62 is configured to penetrate the opening of the outer metal member 70.

[0085] The outer metal member 70 is made of a metal plate with a constant thickness. The thickness of the outer metal member 70 is, for example, several mm or less. In this embodiment, the outer metal member 70 is made of a zinc-plated steel plate with a thickness of 0.5 mm. However, the material and thickness of the outer metal member 70 are not limited to this.

[0086] In this manner, in the molded motor 1 of the present embodiment, one of the coil ends 12a protruding on each of both sides in the axial direction X is covered by the inner metal member 40. As a result, even if a fire breaks out inside the molded resin 30 due to a layer short or the like, the fire can be blocked by the inner metal member 40. This makes it possible to prevent the fire from leaking out of the molded motor 1 and spreading.

[0087] Furthermore, in the molded motor 1 of this embodiment, the other of the coil ends 12a protruding on both sides in the axial direction X is covered with an outer metal member 70. By providing the outer metal member 70 in addition to the inner metal member 40 in this manner, a fire that breaks out inside the molded resin 30 can also be blocked by the outer metal member 70. This makes it possible to further prevent a fire from leaking to the outside of the molded motor 1 and spreading.

[0088] Of the inner metal member 40 and the outer metal member 70, only the inner metal member 40 may be provided. However, by providing both the inner metal member 40 and the outer metal member 70, it is possible to reliably prevent fire from erupting outside the molded motor 1.

[0089] Next, a manufacturing method of the molded motor 1 according to the embodiment will be described with reference to Figs. 7 to 9. Fig. 7 is a diagram for explaining the step of arranging the stator 10 and the inner metal member 40 in the manufacturing method of the molded motor 1 according to the embodiment. Figs. 8A, 8B, and 8C are diagrams for explaining the step of injecting liquid resin 30L into the mold 100 in the same manufacturing method. Fig. 9 is a flowchart for explaining the manufacturing method of the molded motor 1 according to the embodiment.

[0090] 7 and 9, the stator 10 having the stator core 11 around which the coil 12 is wound via the insulator 13 and the inner metal member 40 arranged so as to cover the outside of the stator 10 are placed in the mold 100 of the injection molding machine. At this time, the second bracket 62 is also placed (step S1).

[0091] The mold 100 is made up of a plurality of blocks. The injection molding machine in this embodiment is a vertical type. Therefore, the mold 100 is configured to be opened and closed in the vertical direction.

[0092] Next, as shown in Figures 8A, 8B, 8C, and 9, liquid resin 30L is injected into the interior of the mold 100 through a gate 100G provided in the mold 100 as a resin injection section, and the liquid resin 30L is hardened to form molding resin 30 (step S2).

[0093] Specifically, first, as shown in Fig. 8A, the stator 10, the inner metal member 40, and the second bracket 62 are arranged in a mold 100, and then a pin 101, which is a pin-back pin, is lowered before liquid resin 30L is injected into the mold 100. The pin 101 holds the stator 10 vertically from the upper side to the lower side. The pin 101 is provided on the output shaft 21a side, and holds the insulator 13 from the output shaft 21a side.

[0094] Next, as shown in FIG. 8B, liquid resin 30L is injected into the inside of the mold 100 through the gate 100G while the stator 10 is held down from above by the pin 101. In this embodiment, the liquid resin 30L is injected by a side gate method in which the liquid resin 30L is injected from the side of the molded resin 30 that will become the resin molded product. That is, the gate 100G is located in the radial direction Y (i.e., on the side) of the molded resin 30 after molding. Specifically, the molded resin 30 has the protruding portion 32 as described above, and the gate 100G is provided in a portion corresponding to the protruding portion 32. Therefore, the liquid resin 30L injected into the mold 100 flows as shown by the arrows in FIG. 8B.

[0095] At this time, because gate 100G is located to the side of the resin molded product (molded resin 30), liquid resin 30L flows from bottom to top or from top to bottom around the entire circumferential direction Z. In particular, when liquid resin 30L flows from bottom to top around stator 10, stator 10 tends to rise upward due to being pushed by liquid resin 30L, but in this embodiment, pin 101 holds down stator 10 from above while liquid resin 30L is being injected, so that stator 10 can be prevented from rising.

[0096] In this embodiment, liquid resin 30L is injected into the interior of mold 100 by a direct gate. That is, the injection molding machine in this embodiment is structured such that liquid resin 30L is injected from the sprue directly into the resin molding portion (molding resin 30) of mold 100 through gate 100G without passing through a runner.

[0097] Thereafter, when the liquid resin 30L is filled inside the mold 100, the flow of the liquid resin 30L stops. When filling of the liquid resin 30L is completed, the pins 101 are raised while the liquid resin 30L is in a molten state, as shown in Fig. 8C. As a result, the pinhole marks made in the liquid resin 30L by the pins 101 are filled with the liquid resin 30L.

[0098] Thereafter, although not shown, when the pins 101 have completed rising, the liquid resin 30L is heated and cured to form the molded resin 30. That is, the liquid resin 30L is heated and cured while the pins 101 are in the raised state. This makes it possible to form the molded resin 30 in which the stator 10, the inner metal member 40, and the second bracket 62 are fixed together by the resin.

[0099] After that, the rotor 20 and other components are attached to the stator 10 covered with the molding resin 30, and the molded motor 1 is completed.

[0100] As described above, the manufacturing method of the molded motor 1 according to the present embodiment includes a step (step S1) of arranging the stator 10 having the stator core 11 and the coil 12 wound around the stator core 11, and the inner metal member 40 arranged to cover the outside of the stator 10, in the mold 100, and a step (step S2) of injecting liquid resin 30L into the mold 100 through the gate 100G, which is a resin injection part provided in the mold 100, and hardening the liquid resin 30L to form the molded resin 30. The manufacturing method of the molded motor 1 according to the present embodiment employs a side gate method, and the gate 100G, which is a resin injection part, is located in the radial direction Y of the molded resin 30 after molding.

[0101] In this way, by adopting the side gate method, it is possible to suppress a decrease in the strength of the molded resin 30, even if the inner metal member 40 is arranged so as to cover the outside of the stator 10. This point will be described below.

[0102] As described above, by disposing the inner metal member 40 so as to cover the stator 10, it is possible to prevent fire from escaping to the outside of the molded motor.

[0103] However, when molding the inner metal member 40 and the stator 10 with the molded resin 30, conventionally, the inner metal member 40 and the stator 10 are placed in a mold, and the liquid resin 30L is injected into the mold from above the mold to harden the liquid resin 30L. In this case, if the inner metal member 40 is placed so as to cover the outside of the stator 10, the gap between the outer surface of the inner metal member 40 and the inner surface of the mold becomes narrower than other parts. Therefore, when the liquid resin 30L is injected into the mold, the air in the mold does not escape well. Moreover, if the inner metal member 40 is not placed, air leaks out in the radial direction Y from the gap between the laminated steel plates of the stator core 11. However, if the inner metal member 40 is placed in close contact with the side surface of the stator core 11, air is less likely to leak out from the gap between the laminated steel plates of the stator core 11 to the part located outside the radial direction Y of the inner metal member 40.

[0104] When the inner metal member 40 is arranged in this way, air in the mold is less able to escape when liquid resin is injected from above the mold, and air is less likely to leak out from the gaps between the laminated steel plates of the stator core 11. As a result, "rust" may enter the molded resin 30 in the portion located outside the inner metal member 40 in the radial direction Y, which may cause problems such as a decrease in the strength of the molded resin 30 in the portion located outside the inner metal member 40 in the radial direction Y. Specifically, if "rust" enters a portion visible from the outside, it is a concern that even if the molded motor 1 has no quality problems, the quality may appear inferior. If a large number of "rust" enters the protruding portion 32, the strength of the protruding portion 32 may be decreased. If "rust" enters the vicinity of a portion where high voltage is ignited, it is also a concern that a state in which the insulation distance cannot be secured may occur.

[0105] Incidentally, the "pores" occur when air bubbles are contained in the liquid resin 30L when the liquid resin 30L is injected. If the liquid resin 30L hardens while containing air bubbles, the hardened molding resin 30 will have "pores" which are cavities in the areas where the air bubbles were present. Incidentally, "pores" are sometimes written as "cavities."

[0106] Therefore, in the manufacturing method of the molded motor 1 according to the present embodiment, a side gate system is adopted, and a gate 100G, which is a resin injection portion in the mold 100, is positioned in the radial direction Y of the molded resin 30 after molding.

[0107] As a result, even if the arrangement of the inner metal member 40 makes the gap between the outer surface of the inner metal member 40 and the inner surface of the mold 100 narrower than other parts, the liquid resin 30L can smoothly enter and flow around the gap between the outer surface of the inner metal member 40 and the inner surface of the mold 100. As a result, it is possible to prevent holes from entering the molded resin 30 in the part located on the outer side of the inner metal member 40 in the radial direction Y, and therefore it is possible to prevent a decrease in the strength of the molded resin 30 in the part located on the outer side of the inner metal member 40 in the radial direction Y.

[0108] In particular, when the inner metal member 40 having the first portion 41 with a larger outer diameter than the second portion 42 is disposed as in the present embodiment, the gap between the outer surface of the inner metal member 40 and the inner surface of the mold becomes narrow in the portion corresponding to the first portion 41 with the larger outer diameter. Therefore, the molded resin 30 in the portion corresponding to the first portion 41 is likely to have "voids". Moreover, when the inner metal member 40 having the first portion 41 with a larger outer diameter than the second portion 42 is disposed, the thickness of the molded resin 30 in the portion corresponding to the first portion 41 with the larger outer diameter becomes thinner than the thickness of the molded resin 30 in the portion corresponding to the second portion 42 with the smaller outer diameter. Therefore, a thin portion with a small thickness is generated in a part of the molded resin 30. In this way, not only does the molded resin 30 have "voids" but also the thin portion is generated, and the strength of the molded resin 30 is further reduced.

[0109] In contrast, in the manufacturing method of molded motor 1 in this embodiment, as described above, the side gate method is adopted, and gate 100G, which is the resin injection portion, is located in the radial direction Y of molded resin 30 after molding.

[0110] As a result, even when an inner metal member 40 having a first portion 41 with an outer diameter larger than that of the second portion 42 is arranged, the incorporation of "voids" into the molded resin 30 in the portion corresponding to the first portion 41 of the inner metal member 40 can be effectively prevented, and a decrease in the strength of the molded resin 30 in the portion corresponding to the first portion 41 of the inner metal member 40 can be prevented.

[0111] In the manufacturing method of molded motor 1 according to this embodiment, gate 100G, which is a resin injection portion, is provided at a portion corresponding to protruding portion 32 of molding resin 30. In other words, liquid resin 30L is injected from a portion of mold 100 that corresponds to protruding portion 32.

[0112] As a result, the liquid resin 30L injected into the mold 100 does not flow directly into the gap between the outer surface of the inner metal member 40 and the inner surface of the mold 100, but passes through the part of the mold 100 corresponding to the protruding portion 32 and then flows into the gap between the outer surface of the inner metal member 40 and the inner surface of the mold 100. As a result, the pressure of the liquid resin 30L injected into the mold 100 can be relaxed at the part corresponding to the protruding portion 32. Therefore, the liquid resin 30L can be more smoothly poured into the gap between the outer surface of the inner metal member 40 and the inner surface of the mold 100. Therefore, it is possible to further suppress the intrusion of "slits" into the molded resin 30 in the part located outside the radial direction Y of the inner metal member 40, and therefore it is possible to further suppress the reduction in the strength of the molded resin 30 in the part located outside the radial direction Y of the inner metal member 40.

[0113] Moreover, by injecting the liquid resin 30L from the portion of the mold 100 that corresponds to the protruding portion 32, the liquid resin 30L can be filled without gaps into the portion of the mold 100 that corresponds to the protruding portion 32, even if the protruding portion 32 has a complex shape, such as protruding outward. Conversely, if liquid resin is injected from above the mold as in the conventional method, the liquid resin may not flow around the entire protruding portion 32, resulting in poor moldability. In this way, by injecting the liquid resin 30L from the protruding portion 32, a molded motor 1 with excellent moldability can be manufactured.

[0114] Furthermore, by adopting the side gate method as in this embodiment, it is possible to simultaneously mold a plurality of molded resins 30. In other words, by adopting the side gate method, it is possible to obtain a plurality of molded resins 30 that cover the stator 10 and the inner metal member 40. This improves the productivity of the molded motor 1.

[0115] Furthermore, in the manufacturing method of the molded motor 1 in this embodiment, it is preferable to inject the liquid resin 30L into the mold 100 from multiple locations, not just one location in the portion corresponding to the side of the molded resin 30. In other words, it is preferable that multiple gates 100G, which are resin injection portions, are provided in the mold 100 in the radial direction of the molded resin 30 after molding. This allows the liquid resin 30L to be uniformly filled in the gap between the outer surface of the inner metal member 40 and the inner surface of the mold 100 in the circumferential direction Z as well. Therefore, it is possible to effectively prevent "slits" from entering the molded resin 30 in the portion located outside the inner metal member 40 in the radial direction Y, also in the circumferential direction Z.

[0116] In this case, the gates 100G are preferably provided at least at positions facing each other. That is, two gates G are preferably provided at 180° intervals along the circumferential direction Z. The number of gates 100G may be three or more. In this case, the multiple gates 100G are preferably provided at equal intervals along the circumferential direction Z.

[0117] In the manufacturing method of molded motor 1 in this embodiment, stator 10 is pressed down vertically by pins 101 from the upper side to the lower side while liquid resin 30L is being injected.

[0118] When the side gate method is employed, the stator 10 tends to float up due to the injection of the liquid resin 30L as described above, but by injecting the liquid resin 30L while holding the stator 10 vertically from the top to the bottom with the pins 101, it is possible to prevent the stator 10 from floating up when the liquid resin 30L is injected. This makes it possible to easily form the molded resin 30 in a predetermined shape.

[0119] As described above, according to the manufacturing method of the molded motor 1 of this embodiment, even if the inner metal member 40 is arranged to cover the outside of the stator 10, it is possible to suppress a decrease in the strength of the molded resin 30, etc.

[0120] The molded motor 1 manufactured in this manner has an inner metal member 40 including a first portion 41 located outside the stator 10 in the radial direction Y and a second portion 42 located outside the stator 10 in the radial direction Y and having a shorter distance to the rotating shaft 21 than the first portion 41. As described above, the molded resin 30 is formed by hardening the liquid resin 30L injected from the radial direction Y.

[0121] With this configuration, even when an inner metal member 40 having a first portion 41 with an outer diameter larger than that of the second portion 42 is disposed, it is possible to prevent the intrusion of holes into the molded resin 30 in the portion located on the outer side of the inner metal member 40 in the radial direction Y. This makes it possible to prevent a decrease in the strength of the molded resin 30 in the portion located on the outer side of the inner metal member 40 in the radial direction Y, and the like. This makes it possible to prevent the spread of fire due to ignition without decreasing the strength of the molded resin 30.

[0122] Furthermore, according to the results of experiments conducted by the present inventors, it was found that the strength of the molded resin 30 does not decrease if the thickness of the molded resin 30 is 1 mm or more. Specifically, when BMC (Bulk Molding Compound) unsaturated polyester resin is used as the resin material of the molded resin 30, if the thickness is less than 1 mm, the predetermined strength required for the molded motor cannot be maintained. However, if the thickness of the molded resin 30 is 1 mm or more, the predetermined strength required for the molded motor can be maintained.

[0123] Furthermore, if the molded resin 30 is visible through the glass, the user may feel that the strength of the molded resin 30 has decreased, even if the strength of the molded resin 30 has not actually decreased, which may cause the user to feel uneasy. However, it has been found that if the thickness of the molded resin 30 is 1 mm or more, the molded resin 30 is not visible through the glass, and if the thickness of the molded resin 30 is less than 1 mm, the molded resin 30 begins to be visible through the glass. In the molded motor 1 of this embodiment, the thickness of the molded resin 30 at the first portion 41 of the inner metal member 40 is set to 2 mm.

[0124] Furthermore, so long as the thickness of molded resin 30 in the portion covering the side of stator 10 is 1 mm or more, stepped portion 30a does not necessarily have to be provided on the side of molded resin 30. In other words, so long as the thickness of molded resin 30 in the portion covering the side of stator 10 is 1 mm or more, the outer surface of molded resin 30 in the portion corresponding to first portion 41 of inner metal member 40 does not have to be positioned outer than the outer surface of molded resin 30 in other portions other than the portion corresponding to first portion 41 of inner metal member 40.

[0125] However, if the thickness of the molding resin 30 in the portion covering the side of the stator 10 is made too thick, the external size of the molded motor 1 will become large.

[0126] Therefore, it is preferable that the outer surface of the molded resin 30 in the portion corresponding to the first portion 41 of the inner metal member 40 is flush with the outer surface of the first side wall portion 61b of the first bracket 61 or is located more inward than the outer surface of the first side wall portion 61b. As a result, even if the thickness of the molded resin 30 in the portion corresponding to the first portion 41 of the inner metal member 40 is increased, the outer size of the molded motor 1 does not become larger than that of the molded motor shown in FIG.

[0127] In the molded motor 1 of the present embodiment, the outer surface of the molded resin 30 at the portion corresponding to the first portion 41 of the inner metal member 40 is flush with the outer surface of the first side wall portion 61b of the first bracket 61. This makes it possible to maintain the same outer diameter as the molded motor shown in Fig. 10. In other words, the thickness of the molded resin 30 at the portion corresponding to the first portion 41 of the inner metal member 40 can be maximized without increasing the outer size compared to the molded motor shown in Fig. 10. This makes it possible to realize a molded motor 1 that is small in size, has excellent strength, and is highly reliable.

[0128] As described above, the manufacturing method of the molded motor 1 of this embodiment includes the steps of arranging the stator 10 having the stator core 11 and the coils 12 wound around the stator core 11, and the inner metal member 40 arranged to cover the outside of the stator 10 in the mold 100, and the steps of injecting liquid resin 30L into the mold 100 through a resin injection section 100G provided in the mold 100 and hardening the liquid resin 30L to form the molded resin 30. The resin injection section 100G is located in the radial direction of the molded resin 30.

[0129] As a result, even if the inner metal member 40 is disposed so as to cover the outside of the stator 10, a decrease in the strength of the mold resin 30 can be suppressed.

[0130] In addition, the molded resin 30 after molding has a protrusion 32 that protrudes outward in a radial direction perpendicular to the axial direction of the rotating shaft 21 of the molded motor 1, and the resin injection portion 100G may be provided in a portion corresponding to the protrusion 32.

[0131] During the injection of the liquid resin 30L, it is preferable to hold down the stator 10 vertically from the upper side to the lower side by the pin 101.

[0132] The inner metal member 40 may also include a first portion 41 located radially outside the stator 10, and a second portion 42 located radially outside the stator 10 and whose distance to the rotating shaft 21 is shorter than the distance from the first portion 41 to the rotating shaft 21.

[0133] Furthermore, it is preferable that the coil 12 includes a coil end 12a protruding from the stator core 11 in a direction along the axial center, the first portion 41 facing the coil end 12a, and the second portion 42 facing the stator core 11.

[0134] Moreover, the molded motor 1 of this embodiment includes a stator 10 having a stator core 11 and a coil 12 wound around the stator core 11, a rotor 20 arranged facing the stator 10 and having a rotating shaft 21 extending in the axial direction, a molded resin 30 covering the stator, and an inner metal member 40 including a first portion 41 located outside the stator 10 in a radial direction perpendicular to the axial direction, and a second portion 42 located outside the stator 10 in the radial direction and a distance to the rotating shaft 21 that is shorter than the distance from the first portion 41 to the rotating shaft 21, and having a portion located between the molded resin 30 and the stator 10. The molded resin 30 is formed by hardening liquid resin 30L injected from the radial direction.

[0135] As a result, even if the inner metal member 40 is disposed so as to cover the outside of the stator 10, a decrease in the strength of the mold resin 30 can be suppressed.

[0136] Furthermore, a gate mark 30G may be present at a radially lateral portion of the molding resin 30 when the liquid resin 30L is injected to mold the molding resin 30.

[0137] Moreover, the molding resin 30 may further have a protruding portion 32 that protrudes outward in the radial direction, and the molding resin 30 may be formed by hardening a liquid resin 30L injected from the protruding portion 32.

[0138] Furthermore, a gate mark 30G may be present on the protruding portion 32 when the liquid resin 30L is injected to mold the molding resin 30.

[0139] Furthermore, the molded resin 30 further includes a bracket 61 fixed to the molded resin 30, the bracket 61 having a first side wall portion 61b covering the side surface of the molded resin 30, and the outer surface of the molded resin 30, at least the portion corresponding to the first portion 41, may be flush with the outer surface of the first side wall portion 61b of the bracket 61 or may be located more inward than the outer surface of the first side wall portion 61b.

[0140] Furthermore, the molded resin 30 further includes an outer metal member 70 having a cover portion 61a covering the outer surface located on the axial side of the molded resin 30 and a second side wall portion 72 covering a portion of the outer surface located on the radial side of the molded resin 30, and at least a portion of the outer surface located on the radial side of the molded resin 30 that is not covered by the second side wall portion 72 may be flush with the outer surface of the second side wall portion 72 of the outer metal member 70 or may be located more inward than the outer surface of the second side wall portion 72.

[0141] Moreover, it is preferable that the thickness of the molding resin 30 in the portion corresponding to the first portion 41 is 1 mm or more.

[0142] Moreover, the molding resin 30 may be made of an unsaturated polyester resin.

[0143] (Modification) While the molded motor 1 according to the present disclosure has been described above based on the embodiment, the present disclosure is not limited to the above embodiment.

[0144] For example, in the above embodiment, the outer surface of the molded resin 30 in the portion corresponding to the first portion 41 of the inner metal member 40 is flush with the outer surface of the first side wall portion 61b of the first bracket 61 or is located more inward than the outer surface of the first side wall portion 61b, but this is not limited thereto. Specifically, the outer surface of the molded resin 30 in the portion corresponding to the first portion 41 of the inner metal member 40 may be flush with the outer surface of the second side wall portion 72 of the outer metal member 70 or may be located more inward than the outer surface of the second side wall portion 72 of the outer metal member 70. In other words, at least a part of the portion of the outer surface of the molded resin 30 located on the radial direction Y side that is not covered by the second side wall portion 72 of the outer metal member 70 may be flush with the outer surface of the second side wall portion 72 of the outer metal member 70 or may be located more inward than the outer surface of the second side wall portion 72 of the outer metal member 70. From the viewpoint of increasing the strength of the side of the molded resin 30 as much as possible, the position of the outer surface of the molded resin 30 at the portion corresponding to the first portion 41 of the inner metal member 40 should be made as thick as possible based on the larger outer diameter of the portion covering the side of the molded resin 30 between the outer metal member 70 and the first bracket 61.

[0145] In the above embodiment, the rotor 20 is an IPM rotor, but is not limited to this. For example, when a permanent magnet type rotor is used as the rotor 20, a surface permanent magnet type rotor (SPM rotor, Surface Permanent Magnet rotor) in which multiple permanent magnets are provided on the outer surface of the rotor core may be used. The rotor 20 may also be configured such that bond magnets are embedded in embedding holes provided in the rotor core.

[0146] In addition, in each of the above embodiments, the number of magnetic poles of the rotor 20 is 10 (i.e., the number of permanent magnets 23 is 10), but this is not limited to this. The number of magnetic poles of the rotor 20 can be any number.

[0147] In addition, forms obtained by applying various modifications to the above-described embodiments that a person skilled in the art may conceive are also included in the present disclosure, as well as forms realized by arbitrarily combining the components and functions of the above-described embodiments within the scope that does not deviate from the spirit of the present disclosure. [Industrial Applicability]

[0148] The molded motor of the present disclosure can be used as a motor in various fields, including a fan motor used in air conditioners. [Explanation of symbols]

[0149] 1 Molded motor 10 Stator 11 Stator core 11a York 11b Teeth 11b1 Extension part 12 Coils 12a Coil end 13 Insulator 14 Slots 20 Rotors 21 Rotation axis 21a Output shaft 22 Rotor core 22a Magnet insertion hole 23 Permanent Magnets 30 Molding resin 30a Step 30G Gate mark 30L Liquid Resin 31 Main body 31a 1st opening 31b 2nd opening 32 Protrusion 40 Inner metal member 40a Step 41 Part 1 42 Part 2 51 First bearing 52 No. 2 bearing 61 First bracket (bracket) 61a, 71 Lid 61b 1st side wall part 62 Second Bracket 70 Outer metal parts 72 Second side wall 80 Circuit Board 81 Electric wire 90 Lead Bush 100 Molds 100G Gate (resin injection part) 101 Pin

Claims

1. a stator having a stator core and a coil wound around the stator core; placing an inner metal member arranged to cover the outside of the stator in a die; and forming a molding resin by injecting a liquid resin into the inside of the mold through a resin injection portion provided in the mold and hardening the liquid resin. the resin injection portion is located in a circumferential direction perpendicular to an axial direction and a radial direction of the rotation shaft of the molded motor, the molding resin after molding has a protruding portion protruding outward in the radial direction, The resin injection portion is provided in a portion corresponding to the protrusion. A manufacturing method for a molded motor.

2. During the injection of the liquid resin, the stator is pressed down vertically by a pin. A method for manufacturing the molded motor according to claim 1.

3. 3. The method for manufacturing a molded motor according to claim 1, wherein the inner metal member includes a first portion located outside the stator in the radial direction, and a second portion located outside the stator and a distance to a rotating shaft is shorter than a distance from the first portion to the rotating shaft.

4. 4. The method for manufacturing a molded motor according to claim 3, wherein the coil includes a coil end protruding from the stator core in a direction along an axial center line, the first portion faces the coil end, and the second portion faces the stator core.

5. a stator having a stator core and a coil wound around the stator core; a rotor disposed opposite the stator and having a rotation axis extending in an axial direction; A molding resin that covers the stator; an inner metal member having a portion located between the molding resin and the stator; Equipped with The molding resin is a liquid resin injected from a circumferential direction perpendicular to the axial direction and the radial direction. is hardened and becomes The molding resin further has a protrusion protruding outward in the radial direction, a gate mark formed when the liquid resin is injected to mold the molding resin is present on the protruding portion; Molded motor.

6. the inner metal member includes a first portion located outside the stator in a radial direction perpendicular to the axial direction, and a second portion located outside the stator in the radial direction and a distance to the rotation shaft is shorter than a distance from the first portion to the rotation shaft, The molded motor according to claim 5.

7. Further, a bracket is provided which is fixed to the molding resin, the bracket has a first side wall portion covering a side surface of the mold resin, 6. The molded motor according to claim 5, wherein at least a portion of the outer surface of the molded resin corresponding to the first portion is flush with an outer surface of the first side wall portion of the bracket or is located more inward than the outer surface of the first side wall portion.

8. an outer metal member including a cover portion covering an outer surface of the molded resin located on the axial direction side and a second side wall portion covering a part of the outer surface of the molded resin located on the radial direction side, At least a part of the outer surface located on the radial side of the molding resin that is not covered by the second side wall portion is flush with the outer surface of the second side wall portion of the outer metal member or is located inside the outer surface of the second side wall portion. The molded motor according to claim 5.

9. The thickness of the molding resin at the portion corresponding to the first portion is 1 mm or more. The molded motor according to any one of claims 5 to 8.

10. The molding resin is composed of an unsaturated polyester resin. The molded motor according to any one of claims 5 to 9.

Images