Preparation method of trickling-free motor stator

Abstract

The invention discloses a preparation method of a trickling-free motor stator. The preparation method comprises the following steps: S1, coating an electromagnetic wire with a layer of self-adhesive glue; s2, drying the electromagnetic wire coated with the self-adhesive glue; s3, cutting the foaming insulation paper according to the size of the stator iron core wire embedding groove, completing paper folding, and inserting the foaming insulation paper into the wire embedding groove of the stator iron core; s4, embedding the electromagnetic wire into the wire embedding slot of the stator core, and welding the end part of the electromagnetic wire and the outgoing line to form a winding; and S5, current is introduced into the stator, so that the temperature of the stator core is increased, the self-adhesive layer on the electromagnetic wire is subjected to an adhesive reaction, and an insulating layer with high insulating property and high adhesive strength is formed. The motor stator paint dripping process is reduced, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicle drive motors, and in particular to a method for preparing a paint-drip-free motor stator. Background Art

[0002] At present, the production process of drive motor stators includes: preparing iron core - inserting paper - embedding wire - expanding - twisting - cutting - welding - mechanical and electrical performance inspection - coating - painting - shipment inspection and other processes. Among them, the painting process has become a "stepping stone" in the motor production rhythm due to its large equipment space, long process time, strong odor and other problems.

[0003] The biggest role of the paint dripping process is to effectively fix the straight segment winding of the motor stator in the slot and effectively bond the end winding into one, thereby improving the NVH performance of the motor during operation. The paint dripping process usually includes preheating, paint dripping, gel (curing) and cooling steps, and the whole process takes up to 4 hours. The equipment cost of the paint dripping process accounts for 20% of the equipment cost of the entire stator production line, and the power consumption of the paint dripping equipment accounts for about 40% of the power consumption of the stator production line. The stator paint dripping seriously affects the cost of stator production. Therefore, it is of great significance to replace the paint dripping process in the stator production process with other materials or new processes. Summary of the invention

[0004] The invention provides a method for preparing a paint-dripping-free motor stator, and the invention can improve the production efficiency of the motor stator.

[0005] The technical solutions to the above problems are as follows: A method for preparing a paint-drip-free motor stator comprises the following steps: S1, the electromagnetic wire is coated with a layer of self-adhesive glue; S2, drying the electromagnetic wire coated with the self-adhesive glue; S3, cutting the foam insulation paper according to the size of the wire embedding slot of the stator core and folding the paper, and inserting the foam insulation paper into the wire embedding slot of the stator core; S4, embedding the electromagnetic wire into the wire embedding slot of the stator core, and welding the end of the electromagnetic wire and the lead wire to form a winding; S5, passing current through the stator to heat up the stator core, causing the self-adhesive layer on the electromagnetic wire to undergo a bonding reaction, thereby forming an insulating layer with high insulation performance and high bonding strength.

[0006] Furthermore, in S1, the material of the self-adhesive is CP20-375, and the thickness of the self-adhesive layer is 1-50 μm.

[0007] Furthermore, the drying in S2 is to bake the electromagnetic wire with the self-adhesive adhesive in a circulation oven, with the temperature set at 200° C.-240° C. and the baking time being 25-35 seconds.

[0008] Furthermore, the foamed insulating paper in S3 is composed of a base material and a foaming layer, the base material is one of PPS, PEN, PI, and PEEK, and the foaming layer expands when heated.

[0009] Further, in S5, the temperature of the stator core is raised to 170°C-180°C for 8-10 minutes, the foamed insulation paper in the wire embedding groove of the stator core expands, and the straight section of the electromagnetic wire is fixed in the wire embedding groove of the stator core by the expanded foamed insulation paper.

[0010] The present invention applies CP20-375 self-adhesive glue to the electromagnetic wire, heats and solidifies it to bond the motor stator end windings together. The foamed insulation is inserted into the wire embedding slot of the stator core, and heats and expands to squeeze and fix the windings. The above method eliminates the paint dripping of the motor stator, so the present invention has the following advantages: 1. Reduce the investment cost of motor stator equipment and reduce the energy consumption of production lines.

[0011] 2. Eliminate the paint dripping process in the production of motor stators to improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is the process of the present invention.

[0013] Figure 2 This is a diagram of the stator structure in the present invention.

[0014] Markings in the attached drawings: Electromagnetic wire 1, foamed insulating paper 2, stator core 3, thermosetting resin insulating layer 4. DETAILED DESCRIPTION

[0015] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0016] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential” and the like to indicate orientations or positional relationships, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0017] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0018] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0020] like Figure 1 to Figure 2 As shown, a method for preparing a paint-free motor stator comprises the following steps: S1, a layer of self-adhesive is coated on the electromagnetic wire; in S1, the material of the self-adhesive is CP20-375, and the thickness of the self-adhesive layer is 1-50 μm.

[0021] S2, drying the electromagnetic wire coated with the self-adhesive glue; the drying in S2 is to bake the electromagnetic wire with the self-adhesive glue in a circulation oven, the temperature is set at 200° C.-240° C., and the baking time is 25-35 seconds.

[0022] S3, cut the foamed insulation paper according to the size of the stator core wire slot and fold it, and insert the foamed insulation paper into the stator core wire slot; the foamed insulation paper in S3 is composed of a base material and a foaming layer, the base material is one of PPS (polyphenylene sulfide), PEN (polyethylene naphthalate), PI (polyimide), and PEEK (polyetheretherketone), the foaming layer is made of polyurethane, and the foaming layer will expand when heated.

[0023] S4, embedding the electromagnetic wire into the wire embedding slot of the stator core, and welding the end of the electromagnetic wire and the lead wire to form a winding; S5, pass current through the stator to heat up the stator core, so that the self-adhesive layer on the electromagnetic wire undergoes a bonding reaction, forming an insulation layer with high insulation performance and high bonding strength. In S5, the stator core is heated to 170℃-180℃ for 8-10 minutes, the foamed insulation paper in the wire slot of the stator core expands, and the straight section of the electromagnetic wire is fixed in the wire slot of the stator core by the expanded foamed insulation paper. Example 1

[0024] S1, self-adhesive glue is applied to the electromagnetic wire 1. A layer of 5 μm CP20-375 insulating material is applied to the circumference of the 3.2×2.5 mm electromagnetic wire 1 by roller coating. CP20-375 material is an insulating material produced by WILLE TECH CORP. CP20-375 insulating material has three states: A, B, and C. State A is a liquid with viscosity. In S1, the liquid in state A is applied to the surface of the electromagnetic wire 1.

[0025] S2, drying. The electromagnetic wire 1 with the CP20-375 insulation layer is baked in a circulation oven, the temperature is set to 210±5℃, and the baking time is 30s. The CP20-375 insulation material is dried to the B state, which is a soft, stable and active coating. The coating is still reactive, that is, the coating can be bonded after the motor stator is embedded. The coating in the B state has the characteristics of corrosion resistance and storage stability.

[0026] S3, cut the foamed insulating paper 2 according to the size of the wire embedding slot of the stator core and fold it, and insert the foamed insulating paper 2 into the wire embedding slot of the stator core; the foamed insulating paper in S3 is composed of a base material and a foaming layer, the base material is one of PPS, PEN, PI, and PEEK, and the foaming layer will expand when heated.

[0027] S3, insert the foam insulation paper. Cut the foam insulation paper according to the size of the motor stator slot and fold it, then insert the foam insulation paper into the stator core. The foam insulation paper is made of PPS as the base material and polyurethane as the foaming layer.

[0028] S4, wire embedding. According to the stator winding development diagram, the electromagnetic wire 1 is passed through the wire embedding slot of the stator core 3. After the wire embedding is completed, the end of the electromagnetic wire 1 and the lead wire are welded to form the stator winding.

[0029] S5, electric heating curing. The stator winding is energized to raise the temperature of the stator core 1 to 175°C for 10 minutes; the foamed insulation paper expands due to heat, and the electromagnetic wire 1 is squeezed and fixed in the wire embedding groove under the action of the expansion of the foamed insulation paper; at the same time, the B-state CP20-375 self-adhesive layer on the electromagnetic wire 1 undergoes a bonding reaction to form a C-state thermosetting resin insulation layer 4 with high insulation performance and high bonding strength, so that the end windings are bonded together to improve the NVH performance of the motor stator.

[0030] The thermosetting resin insulation layer 4 in state C was subjected to a withstand voltage test, and the test results were: the power frequency withstand voltage was greater than 2850V, the insulation resistance was greater than 20MΩ, and the PDIV was greater than 1535V, which met the requirements for the use of new energy motors. The present invention also conducted a rolling peeling test on the thermosetting resin insulation layer 4 in state C according to the DIN 1464 standard, and the bonding strength was greater than 80000N / mm. Therefore, the present invention has the characteristics of bonding strength.

[0031] The above embodiments are part of the embodiments of the present invention. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but cannot be simply understood as limiting the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

Claims

1. A method for preparing a paint-free motor stator, characterized in that: The following steps are involved: S1, the electromagnetic wire is coated with a layer of self-adhesive glue; S2, drying the electromagnetic wire coated with the self-adhesive glue; S3, cutting the foam insulation paper according to the size of the wire embedding slot of the stator core and folding the paper, and embedding the foam insulation paper into the wire embedding slot of the stator core; S4, embedding the electromagnetic wire into the wire embedding slot of the stator core, and welding the end of the electromagnetic wire and the lead wire to form a winding; S5, passing current through the stator to heat up the stator core, causing the self-adhesive layer on the electromagnetic wire to undergo a bonding reaction, thereby forming an insulating layer with high insulation performance and high bonding strength.

2. The method for preparing a paint-drip-free motor stator according to claim 1, characterized in that: In S1, the material of the self-adhesive is CP20-375, and the thickness of the self-adhesive layer is 3-10 μm.

3. The method for preparing a paint-free motor stator according to claim 1, characterized in that: The drying in S2 is to bake the electromagnetic wire with self-adhesive in a circulation oven, with the temperature set at 200°C-240°C and the baking time being 25-35s.

4. The method for preparing a paint-drip-free motor stator according to claim 1, characterized in that: The foamed insulating paper in S3 is composed of a base material and a foaming layer, wherein the base material is one of PPS, PEN, PI, and PEEK, and the foaming layer expands when heated.

5. The method for preparing a paint-drip-free motor stator according to claim 1, characterized in that: In S5, the temperature of the stator core is raised to 170°C-180°C for 8-10 minutes, the foamed insulation paper in the wire embedding slot of the stator core expands, and the straight section of the electromagnetic wire is fixed in the wire embedding slot of the stator core by the expanded foamed insulation paper.

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