Novel stator and manufacturing method thereof

Abstract

The invention discloses a novel stator and a manufacturing method thereof, the novel stator comprises an iron core and windings inserted in stator grooves of the iron core, and further comprises a plastic insulating sheath, the plastic insulating sheath is provided with insulating spacer bushes which are arranged in the stator grooves in an injection molding mode and wrap the windings, and the insulating spacer bushes are arranged in the stator grooves. And oil grooves which axially penetrate through the winding, are communicated with the surface of the winding and are used for introducing cooling oil are distributed on the inner surface of each insulating spacer bush around the winding. The novel stator has the advantages of being simple in manufacturing process, high in production efficiency and low in manufacturing cost, cooling oil can be led into the iron core to cool the part, located in the iron core, of the winding, heat can be rapidly dissipated when the stator works, the stator can be applied to occasions with the ultra-high-speed rotation requirement, and the service life of the stator is prolonged. And the performance and service life of the motor are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of motors, and relates to a stator of a motor, and in particular to a novel stator and a manufacturing method thereof. Background Art

[0002] The stator is a key part of the motor, mainly composed of an iron core and windings. The iron core has stator slots distributed along the circumference, and the windings are inserted in each stator slot. In order to prevent electrical breakdown, short circuits between windings, and reduced contact spacing, the stator slots of traditional stators are inserted with insulating paper to isolate them from the windings.

[0003] Since traditional stators use insulating paper for insulation, a special process must be set up during the stator manufacturing process to insert the insulating paper. The process of inserting the insulating paper is cumbersome and requires each stator slot to be inserted one by one, resulting in low production efficiency and high manufacturing costs. In addition, due to the use of insulating paper, it is impossible to cool the winding inside the core by oil cooling. Therefore, the traditional stator has the problem of the winding not being able to dissipate heat quickly during operation, which greatly affects the performance of the stator, making it difficult for the traditional stator to be applied to occasions requiring ultra-high-speed rotation. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a new type of stator with high production efficiency and capable of oil cooling the winding inside the iron core, so as to overcome the shortcomings of the prior art.

[0005] A novel stator comprises an iron core and windings inserted in respective stator slots of the iron core, characterized in that: it also comprises a plastic insulating sheath, the plastic insulating sheath comprises insulating spacers which are injection-molded in respective stator slots and wrap the windings, and the inner surface of each insulating spacer is provided with an oil groove which axially penetrates the winding and communicates with the surface of the winding and is used for passing cooling oil.

[0006] By adopting the above technical scheme, the present invention adopts a plastic insulating sheath, and arranges the plastic insulating sheath as an insulating spacer which is injection molded in each stator slot and wraps the winding, and the inner surface of the insulating spacer is arranged to surround the winding and has an oil groove which penetrates axially and communicates with the surface of the winding. On the one hand, since the plastic insulating sheath can be directly injection molded in the stator slot of the iron core by injection molding, the process is simple and the production efficiency is high; on the other hand, since the insulating spacer is made of plastic, an oil groove can be made on the plastic, and the winding can be cooled by passing cooling oil into the oil groove to take away the heat generated during the working process of the winding, so that the stator can dissipate heat in time when working, so that the stator can be used in occasions with ultra-high-speed rotation requirements, thereby improving the performance and life of the motor.

[0007] In the present invention, the plastic insulating sheath further has insulating end plates located at both ends of the insulating spacer and covering the end surfaces of both ends of the iron core. Adding insulating end plates to the plastic insulating sheath can reduce axial shrinkage during injection molding and prevent axial displacement during copper wire insertion.

[0008] In the present invention, the end faces of both ends of the core are radially divided into an inner ring end face and an outer ring protrusion protruding from the inner ring end face, the insulating end plate covers the inner ring end face, and the surface of the insulating end plate is flush with the surface of the outer ring protrusion.

[0009] In the present invention, the iron core is axially divided into an upper section and a lower section, and the plastic insulating sheath further comprises an insulating partition located in the middle of the insulating spacer and spaced between the upper section and the lower section. The added insulating partition can further reduce axial shrinkage during the injection molding process.

[0010] In the present invention, the iron core is radially divided into an inner ring groove and an outer ring connecting portion located outside the inner ring groove and connecting the upper section and the lower section at the axial middle position, and the insulating partition is located in the inner ring groove.

[0011] In the present invention, the winding is composed of a plurality of flat wires, and the oil groove is located at the top corner of each flat wire. The oil groove is arranged at the top corner of each flat wire to avoid the plastic insulating sheath from contacting the four corners of the flat wire, so as to prevent the insulating sheath from scratching the insulating paint of the winding during the insertion of the flat wire.

[0012] In the present invention, the upper section and the lower section are both formed by stacking complete silicon steel sheets, the outer ring protrusion and the outer ring connecting portion are both formed by stacking incomplete silicon steel sheets, the complete silicon steel sheet has an inner ring annular region and an outer ring annular region in the radial direction, the inner ring annular region has stator slot holes that are stacked to form stator slots at equal intervals along the circumferential direction, and the incomplete silicon steel sheet only has the outer ring annular region and does not have the inner ring annular region. By stacking complete silicon steel sheets and incomplete silicon steel sheets, the manufactured iron core can have outer ring protrusions at both ends and inner ring partitions in the axial middle position, and thus the plastic insulating sheath manufactured by injection molding can have insulating end plates and middle partitions that are integrated with the insulating spacer.

[0013] The present invention further comprises a cooling cover connected to the insulating end plate. The cooling cover and the oil groove can form a flow space for cooling oil.

[0014] In addition, another technical problem to be solved by the present invention is to provide a method for manufacturing a novel stator, which is:

[0015] After placing the core molds in the stator slots of the iron core, the core molds are placed in an injection mold to form a cavity in the shape of the plastic insulating sheath in the injection mold set;

[0016] After injecting molten plastic into the mold cavity and cooling it, the injection mold set is opened and the core mold is pulled out, so that the plastic insulating sheath is fixed in the iron core;

[0017] inserting windings into each of the insulating spacers of the plastic insulating sheath;

[0018] Cooling covers are welded on the insulating end plates at both ends of the plastic insulating sheath.

[0019] By adopting the above technical scheme, it can be known that the new stator of the present invention has the advantages of simple manufacturing process, high production efficiency and low manufacturing cost, and can also realize the cooling oil passing into the inside of the iron core to cool the part of the winding located inside the iron core, so that the stator can dissipate heat quickly when working, so that the stator can be used in occasions with ultra-high-speed rotation requirements, thereby improving the performance and life of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0021] Figure 1 It is a three-dimensional schematic diagram of the novel stator of the present invention;

[0022] Figure 2 It is an exploded schematic diagram of the novel stator of the present invention;

[0023] Figure 3 It is a three-dimensional schematic diagram of the iron core of the present invention;

[0024] Figure 4 It is an exploded schematic diagram of the iron core of the present invention;

[0025] Figure 5 It is a partial enlarged top view of the novel stator of the present invention at the stator slot;

[0026] Figure 6 A structural cross-sectional view of a novel stator with a cooling cover according to the present invention;

[0027] Figure 7 Another structural cross-sectional view of the novel stator with a cooling cover of the present invention. DETAILED DESCRIPTION

[0028] like Figure 1 and Figure 2 As shown, the novel stator of the present invention comprises an iron core 100 , a winding 200 and a plastic insulating sheath 300 .

[0029] Combination Figure 3 and Figure 4The core 100 is made of stacked silicon steel sheets. The core 100 is a cylindrical structure with an axially extending rotor accommodating cavity 107 inside. The end surface of the core 100 is circumferentially and evenly spaced with axially penetrating stator slots 101. In this embodiment, the core 100 is axially divided into an upper section 110 and a lower section 120. The end surfaces at both ends of the core 100 are radially divided into an inner ring end surface 102 and an outer ring protrusion 103 protruding from the inner ring end surface 102. The core 100 is radially divided into an inner ring partition groove 104 and an outer ring connecting portion 105 located on the periphery of the inner ring partition groove 104 and connecting the upper section 110 and the lower section 120 in the axial middle position.

[0030] Specifically, the upper section 110 and the lower section 120 are both formed by stacking complete silicon steel sheets; the outer ring protrusion 103 and the outer ring connecting portion 105 are both formed by stacking incomplete silicon steel sheets, thereby forming the above-mentioned core structure of this embodiment. The so-called complete silicon steel sheet refers to a silicon steel sheet including a stator slot hole 133. The complete silicon steel sheet is radially (in Figure 4 The incomplete silicon steel sheet is divided into an inner annular region 131 and an outer annular region 132 by a dashed line, wherein the stator slots 133 are circumferentially spaced apart on the inner annular region 131. The so-called incomplete silicon steel sheet refers to a silicon steel sheet without the stator slots 133, that is, the incomplete silicon steel sheet only has the outer annular region 132 and does not have the inner annular region 131.

[0031] In addition, the inner diameter edge of the complete silicon steel sheet also has a notch connecting the center hole and the stator slot hole 133, so that the stacked core has an axially extending slot 106 at the inner diameter edge. The slot 106 connects the rotor accommodating cavity 107 and the stator slot 101. In this embodiment, the cross section of the stator slot 101 is rectangular, that is, the stator slot hole 133 is rectangular.

[0032] For example Figure 2 As shown, the plastic insulating sheath 300 is an integral structure, which is fixed in the iron core 100 by injection molding, and has an insulating spacer 310 located in each stator slot 101, an insulating end plate 320 connected to both ends of the insulating spacer 310, and an insulating partition 330 connected to the axial middle position of the insulating spacer 310. Among them, the insulating end plate 320 is embedded in the inner ring end face 102 of the iron core 100, and the surface of the insulating end plate 320 is flush with the surface of the outer ring protrusion 103, and the insulating partition 330 is embedded in the inner ring partition groove 104 of the iron core 100. Due to the positioning of the insulating end plate 320 and the insulating partition 330, the plastic insulating sheath 300 will not shrink axially during the injection molding process, and the entire plastic insulating sheath 300 is firmly fixed in the iron core 100, without the risk of falling off, and can also prevent axial displacement during the insertion of the copper wire.

[0033] In addition, the inner diameter surface of the plastic insulating sheath 300 is also embedded with ribs 301 of the slot 106 . The ribs 301 can further improve the strength of the plastic insulating sheath 300 .

[0034] Combination Figure 5 As shown, the winding 200 is inserted into the insulating spacer 310 of the plastic insulating sheath 300. The insulating spacer 310 plays the role of insulating the slot portion of the winding 200 and the iron core 100. The slot portion of the winding 200 is composed of a plurality of rectangular flat wires 201 arranged in an array.

[0035] In order to cool the winding, the inner surface of the insulating spacer 310 is provided with oil grooves 311 for passing cooling oil at intervals around the inner groove part of the winding 200. The oil groove 311 has an opening 312 facing the inner groove part of the winding 200, so that the oil groove 311 can be connected with the inner groove part of the winding 200. In this way, when the cooling oil flows through the oil groove 311, the cooling oil contacts the surface of the winding, and then can take away the heat of the inner groove part of the winding 200, so as to cool the inner groove part of the winding 200. In this embodiment, each oil groove 311 is located at each vertex position of the flat wire 201. The distribution of the oil grooves 311 in this way can avoid the plastic insulating sheath 300 from contacting the four corners of the flat wire 201, so as to prevent the insulating paint of the winding 200 from being scratched.

[0036] After the winding 200 is inserted into the iron core 100, both ends of the winding 200 have exposed ends 202 protruding out of the iron core 100. Figure 6 As shown, the present invention further includes cooling covers 400 respectively covering the two exposed ends 202 and the oil groove 311. The cooling cover 400 is integrally formed by an inner ring wall 401, an outer ring wall 402, and a top wall 403 connected to the outer end of the inner ring wall 401 and the outer end of the outer ring wall 402. The cooling cover 400 is also made of insulating plastic, and can be made of the same plastic material as the plastic insulating sheath 200.

[0037] By welding the inner end of the inner ring wall 401 and the inner end of the outer ring wall 402 to the insulating end plate 320 of the plastic insulating sheath 200 , an annular cooling cavity 404 connecting the oil grooves 311 is formed between the cooling cover 400 and the exposed end 202 of the core 100 .

[0038] In this embodiment, of the two cooling covers 400 at both ends of the iron core 100, one cooling cover 400 is provided with an oil inlet 501, and the other cooling cover 400 is provided with an oil outlet 502. In this way, the cooling oil can enter the cooling cover 400 from the oil inlet 501, first cool the exposed end 202 of the winding in the cooling cover 400, then enter the oil groove 311 inside the iron core 100 to cool the winding part inside the iron core 100, then flow into the cooling cover 400 at the other end, cool the exposed end 202 of the winding in the cooling cover 400, and finally flow out from the oil outlet 502.

[0039] In other embodiments, Figure 7 As shown, oil outlets 502 may be provided on both cooling covers 400, and an oil inlet 501 leading to the oil groove 311 may be provided on the outer surface of the axial middle position of the iron core 100. In this way, the cooling oil is introduced into the oil groove 311 from the middle position of the iron core 100, and the cooling oil entering the oil groove 311 flows to both ends of the iron core 100 to cool the winding part inside the iron core 100, and finally enters the cooling cavity 404 of the cooling covers 400 at both ends to cool the exposed end 202 of the winding and then flows out from the oil outlet 502.

[0040] The above is the novel stator of the present invention, and the manufacturing method thereof is as follows:

[0041] First, after placing the core mold in each stator slot of the iron core, the core mold is placed in an injection mold together, and a cavity having the shape of the plastic insulating sheath is formed in the injection mold;

[0042] Then, after the molten plastic is injected into the mold cavity and cooled, the injection mold set is opened and the core mold is pulled out, so that the plastic insulating sheath is fixed in the iron core;

[0043] Then, insert the windings into the respective insulating sleeves of the plastic insulating sheath;

[0044] Finally, the prepared cooling cover is welded to the insulating end plates of the plastic insulating sheath at both ends of the iron core to cover the exposed ends of the winding and the oil tank.

[0045] Through the above detailed description, it can be seen that the new stator of the present invention can use injection molding to fix the plastic insulating sheath in the stator slot of the iron core to replace the insulating paper to achieve the insulation of the winding and the iron core. Compared with the traditional method of using insulating paper, the process is simple and the production efficiency is high, which is beneficial to reduce the cost of stator manufacturing. In addition, the use of plastic insulating sheath can also realize the cooling oil passing into the inside of the iron core to cool the part of the winding located inside the iron core, so that the stator can quickly dissipate heat when working, so that the stator can be used in occasions with ultra-high-speed rotation requirements, thereby improving the performance and life of the motor.

Claims

1. A novel stator, comprising an iron core and windings inserted into each stator slot of the iron core, characterized in that: It also includes a plastic insulating sheath, which has an insulating spacer that is injection-molded in each of the stator slots and wraps the winding. The inner surface of each insulating spacer is provided with an oil groove that axially penetrates the winding and communicates with the surface of the winding and is used to pass cooling oil.

2. The novel stator according to claim 1 is characterized in that: The plastic insulating sheath also has insulating end plates which are located at both ends of the insulating spacer and cover the end surfaces of both ends of the iron core.

3. The novel stator according to claim 2 is characterized in that: The end faces of both ends of the core are radially divided into an inner ring end face and an outer ring protrusion protruding from the inner ring end face, the insulating end plate is covered on the inner ring end face, and the surface of the insulating end plate is flush with the surface of the outer ring protrusion.

4. The novel stator according to claim 3 is characterized in that: The iron core is divided into an upper section and a lower section along the axial direction, and the plastic insulating sheath further comprises an insulating partition plate located in the middle of the insulating spacer and spaced between the upper section and the lower section.

5. The novel stator according to claim 4 is characterized in that: The iron core is radially divided into an inner ring partition groove and an outer ring connecting portion located outside the inner ring partition groove and connecting the upper section and the lower section at an axial middle position, and the insulating partition plate is located in the inner ring partition groove.

6. The novel stator according to claim 1 is characterized in that: The winding is composed of a plurality of arranged flat wires, and the oil groove is located at the top corner of each flat wire.

7. The novel stator according to claim 4 is characterized in that: The upper section and the lower section are both formed by stacking complete silicon steel sheets, the outer ring protrusion and the outer ring connecting portion are both formed by stacking incomplete silicon steel sheets, the complete silicon steel sheet has an inner ring annular area and an outer ring annular area in the radial direction, the inner ring annular area has stator slot holes that are stacked to form stator slots at equal intervals along the circumferential direction, and the incomplete silicon steel sheet only has the outer ring annular area, and does not have the inner ring annular area.

8. The novel stator according to claim 4 is characterized in that: Also included is a cooling shroud connected to the insulating end plate.

9. A method for manufacturing a novel stator according to any one of claims 1 to 7, characterized in that: After placing the core molds in the stator slots of the iron core, the core molds are placed in an injection mold to form a cavity in the shape of the plastic insulating sheath in the injection mold set; After injecting molten plastic into the mold cavity and cooling it, the injection mold set is opened and the core mold is pulled out, so that the plastic insulating sheath is fixed in the iron core; A winding is inserted into each of the insulating sleeves of the plastic insulating sheath.

10. The method for manufacturing the novel stator according to claim 9, characterized in that: Cooling covers are welded on the insulating end plates at both ends of the plastic insulating sheath.

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