Efficient rubber coating and injection molding method for iron cores of inner stator and rotor of motor

Abstract

The invention relates to the technical field of injection molding, in particular to a high-efficiency encapsulation injection molding method for iron cores of a motor inner stator and a motor rotor, which comprises the following steps of: A, pre-classifying the iron cores; b, preparing a mold structure; c, matching and mounting gaskets; d, loading the iron core; and E, injection molding. Through iron core pre-classification, preparation of the adjustable gasket combination in the mold insert and accurate matching and installation of the gaskets, the size of the mold cavity can dynamically, efficiently and accurately adapt to iron core laminations with different thickness deviations. And the purchase cost of the iron core coiled material is reduced. And meanwhile, by adjusting the gasket combination instead of manufacturing inserts with various heights, the machining cost and the management complexity of mold spare parts are effectively reduced. The common defects of excessive flashes, unqualified appearance and size and the like in rubber-coated injection molding products are thoroughly eliminated, the product quality is ensured, the production efficiency and the material utilization rate are improved, and therefore the problem of high production cost in a traditional process is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of injection molding, and in particular to a high-efficiency glue-coating injection molding method for the iron core of a stator and a rotor in a motor. Background Art

[0002] During the overmolding process of the stator and rotor cores in electric motors, variations in the total thickness of the core laminations are unavoidable. This is primarily due to the cumulative effect of individual lamination thickness tolerances and stacking tolerances, resulting in the total height of each stamped core lamination batch fluctuating between 0.05mm and 0.25mm. Traditional injection molds typically utilize fixed-size cavities, which present significant challenges when faced with core lamination thickness variations.

[0003] Specifically, when the core laminations are too thin, the gap between them and the top surface of the mold cavity increases, resulting in defects such as excess glue or excessive glue thickness in the injection molded product. Conversely, when the core laminations are too thick, the cavity space becomes smaller, which can easily lead to insufficient glue, thin glue, and even deformation of the core laminations due to excessive squeezing, resulting in scrapped products.

[0004] To address these issues, existing technologies typically employ two costly solutions: First, strictly tightening the tolerances for the placement of individual core laminations significantly increases the procurement cost of the core lamination coils; second, manufacturing rear mold inserts of varying heights to accommodate core lamination thicknesses, which also significantly increases the processing cost and management complexity of the mold spare parts. Neither approach meets the modern industry's demand for low-cost, fast, efficient, and high-precision production.

[0005] Therefore, there is a need for an injection molding method that can efficiently and accurately adapt to the total thickness deviation of the core laminations and effectively solve the product defects and high production costs caused by this. Summary of the Invention

[0006] The purpose of the present invention is to address the deficiencies of the existing technology and provide a method for efficient overmolding of the stator and rotor cores of motors. By pre-classifying the cores, preparing an adjustable gasket combination in the mold inserts, and accurately matching and installing the gaskets, the mold cavity size can dynamically, efficiently, and accurately adapt to core laminations with different thickness deviations. This reduces the procurement cost of the core coils. At the same time, by adjusting the gasket combination rather than manufacturing inserts of various heights, the processing cost and management complexity of the mold spare parts are effectively reduced. This completely eliminates common defects in overmolded products, such as burrs, unqualified appearance, and dimensions, ensuring product quality, improving production efficiency and material utilization, and thus solving the problem of high production costs in traditional processes.

[0007] To achieve the above-mentioned purpose, the present invention provides a method for high-efficiency overmolding of the stator and rotor cores of a motor, comprising the following steps: A. Core pre-classification: core lamination sets are classified into different thickness deviation levels according to the thickness of the core laminations; B. Mold Structure Preparation: The overmolded injection mold includes an insert structure, which is disposed in the rear mold or front mold of the mold. The insert structure is provided with multiple gaskets of different thicknesses that can adjust the mold cavity size. The multiple gaskets are stacked to form multiple pre-selected gasket combinations, which are used to match core lamination sets with different thickness deviation levels; C. Gasket matching and installation: According to the core lamination sets with different thickness deviation levels, select and install the matching pre-selected gasket combination in the insert structure to adjust the mold cavity size; D. Core loading: Position the core laminations and load them into the mold cavity; E. Injection molding: close the mold and injection mold the core laminations.

[0008] Preferably, the insert structure includes a first insert and a second insert. The first insert is provided with a cavity for accommodating the core laminations to be overmolded; The first insert is embedded inside the second insert; A fixing piece is provided in the cavity, the upper end of the fixing piece contacts the front mold, the lower end of the fixing piece contacts the rear mold, and the core laminations are fixed between the fixing piece and the first insert.

[0009] Preferably, it is characterized in that the front mold is provided with a front inner mold, and the front inner mold is arranged on the inner side of the front mold; The rear mold is provided with a rear inner mold and a push plate, the rear inner mold is provided inside the rear mold, and the push plate is provided at one end of the rear inner mold close to the front inner mold; A sliding block is provided between the front mold and the rear mold, wherein the upper portion of the sliding block contacts the front inner mold, and the lower portion of the sliding block contacts the push plate; The front mold, the front inner mold, the rear mold, the rear inner mold, the push plate and the sliding block form a mold cavity.

[0010] Preferably, one end surface of the sliding block contacts the outer surface of the first insert; The inner sides of the rear inner mold and the push plate are in contact with the outer side surface of the second insert.

[0011] Preferably, the fixing member includes a first fixing block and a second fixing block, and the first fixing block and the second fixing block are fixed by bolts; The upper end of the first fixing block contacts the front mold, and the lower end of the second fixing block contacts the rear mold.

[0012] Preferably, the plurality of gaskets of different thicknesses include a first gasket, a second gasket, a third gasket and a slider gasket; The first gasket, the third gasket and the slider gasket are all provided with thin sheet type and thick sheet type, the thickness of the thick sheet type is thicker than that of the thin sheet type, and the thickness of the second gasket is fixed; The first gasket, the third gasket, the slider gasket and the second gasket of different thicknesses are combined to form a plurality of preselected gasket combinations.

[0013] Preferably, the specific method of installing the gasket is: The first gasket and the second gasket are arranged on the bottom of the second insert; The third gasket is arranged at the bottom of the first insert and contacts the bottom of the second gasket and the bottom of the core lamination respectively; The slider pad is arranged on a side of the sliding block close to the front inner mold.

[0014] Preferably, the specific method of gasket matching is: a. According to the actual total thickness T of the core lamination 实际 The ideal total core thickness T set by the mold 理想 Thickness deviation ΔT=T 实际 -T 理想 , determine the amount of movement ΔZ that needs to be adjusted on the top surface of the first insert 镶件 , where ΔZ 镶件 =T 理想 -T 实际 ; b. When the core lamination thickness deviation ΔT<0, T 实际 <T 理想 , resulting in ΔZ 镶件 >0, the first insert needs to be moved down, and from the pre-selected gasket combination, a thick first gasket, a thin third gasket, and a thin slider gasket are selected so that the total thickness change of the pre-selected gasket combination is equal to the movement amount ΔZ that the top surface of the first insert needs to be adjusted. 镶件 Matching, thereby achieving a corresponding lowering of the top surface of the first insert; c. When the core lamination thickness deviation ΔT>0, T 实际 >T 理想 , resulting in ΔZ 镶件 <0, the first insert needs to be moved up, and from the pre-selected gasket combination, a thin-type first gasket, a thick-type third gasket, and a thick-type slider gasket are selected so that the total thickness change of the pre-selected gasket combination is equal to the movement amount ΔZ that the top surface of the first insert needs to be adjusted. 镶件 Matching, thereby achieving a corresponding increase in the top surface of the first insert.

[0015] Preferably, the iron core pre-classification step includes: sorting the iron core lamination sets with different thickness deviation levels from large to small according to quantity, and selecting them as priority overmolding batches for processing in sequence.

[0016] Preferably, the thickness of the core laminations is measured after compaction, and the compaction pressure of the core laminations is equal to the holding pressure of the overmolding injection mold.

[0017] The present invention offers the following benefits: By pre-sorting the cores, preparing adjustable shim combinations within the mold inserts, and precisely matching and installing the shims, the mold cavity size can dynamically, efficiently, and precisely adapt to core laminations with varying thickness variations. This reduces the procurement cost of core coils. Furthermore, by adjusting the shim combination rather than manufacturing inserts of varying heights, the processing cost and management complexity of mold spare parts are effectively reduced. This completely eliminates common defects in overmolded products, such as burrs, substandard appearance, and dimensional quality, ensuring product quality and improving production efficiency and material utilization, thereby addressing the high production costs associated with traditional processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a flowchart of the steps of the overmolding method of the present invention.

[0019] Figure 2 It is a schematic cross-sectional structural diagram of the overmolding injection mold of the present invention.

[0020] Figure 3 It is a schematic cross-sectional structural diagram of the insert structure of the present invention.

[0021] Figure 4 It is a schematic diagram of the cross-sectional structure of the insert structure and the rear mold of the present invention.

[0022] Reference numerals include: 1. Core laminations; 2. Insert structure; 21. First insert; 22. Second insert; 221. Limiting edge; 222. Inclined surface; 23. Fixing piece; 231. First fixing block; 232. Second fixing block; 233. Limiting slot; 3. Rear mold; 31. Rear inner mold; 311. Limiting slot; 32. Push plate; 321. Oblique veneer; 4. Front mold; 41. Front inner mold; 5. Sliding block; 6. First gasket; 7. Second gasket; 8. Third gasket; 9. Slider gasket. DETAILED DESCRIPTION

[0023] The present invention is described in detail below with reference to the accompanying drawings.

[0024] like Figures 1 to 4 As shown, the present invention provides a method for high-efficiency glue-coating injection molding of the stator and rotor core of a motor, comprising the following steps: A. Iron core pre-classification: Classify the iron core laminations 1 into sets of iron core laminations with different thickness deviation levels according to their thickness; and realize grading the iron core laminations 1 in production according to thickness deviation.

[0025] B. Mold Structure Preparation: The overmolded injection mold includes an insert structure 2, which is installed in the rear mold 3 or front mold 4 of the mold. The insert structure 2 is equipped with multiple shims of different thicknesses that can adjust the mold cavity size. These shims are stacked to form multiple pre-selected shim combinations. These shim combinations are used to match core laminations with different thickness tolerance levels. An adjustable structure formed by stacking multiple shims of different thicknesses is set in the mold insert. The mold cavity size is adjusted through the shim combination to make the mold adaptable to core laminations of different thicknesses. This eliminates the need to strictly tighten the admission tolerance of a single core, reducing the procurement cost of the core coil.

[0026] C. Shim Matching and Installation: Pre-selected shim combinations matching the thickness tolerance levels of core laminations are selected and installed in the insert structure 2 to adjust the mold cavity dimensions. Based on the thickness tolerance of the core laminations 1 to be processed, the corresponding shim combination is selected and installed to precisely adjust the mold cavity height or depth. Simply adjusting the shim combination to accommodate the thickness tolerance of the core laminations 1 eliminates the need to manufacture inserts of varying heights to accommodate varying thicknesses. This reduces the cost and management complexity of mold spare parts. Furthermore, the mold can efficiently and accurately accommodate the overall thickness tolerance of the core laminations 1.

[0027] D. Core Loading: Position and load the core lamination 1 into the mold cavity; ensure that the core lamination 1 is accurately positioned and supported in the mold, thereby avoiding defects caused by uneven core thickness during the injection molding process.

[0028] E. Injection Molding: Close the mold and injection mold the core laminations 1. This produces an overmolded core with no flash (flaking or burrs on the product edge or parting line), and a qualified appearance and dimensions. This solves the product defects and high production costs caused by uneven core thickness in traditional processes, achieving efficient production and high-quality output.

[0029] During the working process, first, the core laminations 1 are pre-classified before the injection molding operation. According to the thickness deviation of the core laminations 1, the core laminations 1 are divided into core lamination sets with different thickness deviation levels, laying the foundation for subsequent precise processing.

[0030] Secondly, the mold structure of the overmolded injection mold features a pre-configured adjustable mold cavity. The key to the overmolded injection mold lies in its insert structure 2, which cleverly incorporates multiple shims of varying thicknesses to adjust the mold cavity size. These shims can be stacked to create multiple preselected shim combinations, each designed to precisely match a core lamination set within a specific thickness tolerance. This allows the overmolded injection mold to be flexibly adjusted during production based on actual conditions.

[0031] Next, shim matching and installation are performed. Based on the thickness deviation of the current core lamination set, a matching pre-selected shim assembly is selected and installed in the insert structure 2. The key to this step is adjusting the mold cavity dimensions to ensure that the mold cavity matches the actual thickness of the current core laminations 1, eliminating gaps or extrusion problems caused by uneven thickness.

[0032] After adjusting the mold cavity dimensions, the core laminations 1 are precisely positioned and loaded into the mold cavity. The overmolding mold is then closed and injection molding begins. Because the mold cavity dimensions are optimized for the thickness of the core laminations 1, the injection molding process proceeds smoothly and efficiently.

[0033] Ultimately, this method ensures that the resulting overmolded cores are free of burrs and meet acceptable appearance and dimensions. This not only addresses the quality issues often encountered in traditional processes, but also significantly improves production efficiency and material utilization.

[0034] like Figures 2 to 3 As shown, the insert structure 2 of this embodiment includes a first insert 21 and a second insert 22. The first insert 21 is provided with a cavity for accommodating the core lamination 1 to be overmolded; The first insert 21 is embedded inside the second insert 22. This precise matching insert structure 2 provides structural guarantee for the stability and adjustment capability of the mold cavity, which is the basis for achieving subsequent precise injection molding.

[0035] A fixing member 23 is provided within the cavity. The upper end of the fixing member 23 contacts the front mold 4, and the lower end of the fixing member 23 contacts the rear mold 3. The core laminate 1 is fixed between the fixing member 23 and the first insert 21. This ensures that the core laminate 1 is firmly fixed between the fixing member 23 and the first insert 21. This ensures the precise and stable position of the core laminate 1 during the injection molding process, avoiding defects such as incomplete injection and burrs caused by core displacement or shaking in traditional processes, thereby improving the quality of the finished overmolded core.

[0036] like Figure 2 As shown, the front mold 4 of this embodiment is provided with a front inner mold 41 , and the front inner mold 41 is provided on the inner side of the front mold 4 .

[0037] The rear mold 3 is provided with a rear inner mold 31 and a push plate 32 . The rear inner mold 31 is provided on the rear inner mold 31 , and the push plate 32 is provided at one end of the rear inner mold 31 close to the front inner mold 41 .

[0038] A sliding block 5 is provided between the front mold 4 and the rear mold 3. The upper part of the sliding block 5 contacts the front inner mold 41, and the lower part of the sliding block 5 contacts the push plate 32. The sophisticated design of the sliding block 5 and the push plate 32 enhances the overall rigidity and sealing of the mold cavity, effectively preventing problems such as overflow (burst) or dimensional instability during the injection molding process, thereby ensuring that the overmolded iron core has no burst and is qualified in appearance and size.

[0039] The front mold 4, front inner mold 41, rear mold 3, rear inner mold 31, push plate 32, and slide block 5 together form the mold cavity. Rather than simply two mold pieces enclosing each other, the mold cavity is constructed collaboratively by multiple components. This ensures high stability and precision during the injection molding process. This provides a solid, seamless mold cavity for precise encapsulation of the core laminations 1, laying the foundation for high-quality injection molding.

[0040] like Figure 2 As shown, one side end face of the sliding block 5 of this embodiment is in contact with the outer side face of the first insert 21, thereby ensuring the lateral position stability of the first insert 21 in the mold cavity and avoiding the lateral displacement or shaking of the first insert 21 during the injection molding process, thereby ensuring the lateral dimensional accuracy of the mold cavity and effectively preventing the problem of burrs or inaccurate dimensions on the side of the product.

[0041] The inner sides of the rear inner mold 31 and the push plate 32 both contact the outer side of the second insert 22. This ensures that the second insert 22 is dually supported and enclosed within the mold by the rear inner mold 31 and the push plate 32. This multi-point contact structure enhances the overall rigidity and stability of the second insert 22 within the mold, ensuring the overall structural integrity and dimensional accuracy of the mold cavity. This ensures effective resistance to deformation under injection pressure, further ensuring that the overmolded core is free of burrs and meets acceptable appearance and dimensions.

[0042] like Figure 4 As shown, in actual use, a limiting edge 221 is provided at the bottom of the second insert 22, and a limiting groove 311 is provided on the inner side of the rear inner mold 31. The limiting edge 221 is embedded in the limiting groove 311, so that the inner side of the rear inner mold 31 abuts the outer side of the second insert 22. An inclined surface 222 is provided on the outer side of the upper portion of the second insert 22, and an inclined surface 321 is provided on the inner side of the push plate 32. The inclined surface 321 abuts against the inclined surface 222, so that the outer side of the second insert 22 abuts against the inner side of the push plate 32. This ensures that the second insert 22 is dually supported and enclosed by the rear inner mold 31 and the push plate 32 within the mold, thereby confining the second insert 22 to the rear mold 3.

[0043] like Figures 2 to 3 As shown, the fixing member 23 of this embodiment includes a first fixing block 231 and a second fixing block 232, which are fixed by bolts. This means that the fixing member 23 is not a one-piece structure, but rather consists of the first and second fixing blocks 231, 232, which are fixed by bolts. This modular design allows for flexible assembly and disassembly of the fixing member 23, making it easier to maintain, clean, or replace worn parts of the mold, thereby improving the mold's maintainability and service life.

[0044] The upper end of the first fixing block 231 contacts the front mold 4, and the lower end of the second fixing block 232 contacts the rear mold 3. When the mold is closed, the fixing member 23 can obtain dual, stable support and positioning from the front mold 4 and the rear mold 3 in the vertical direction. This fixing mechanism with two-way contact between the upper and lower parts ensures the high stability of the core lamination 1 in the mold cavity. It effectively prevents the core lamination 1 from axial displacement or tilting due to force during the injection molding process, thereby ensuring the accuracy of the rubber-coated injection-molded iron core and avoiding defects such as unsatisfactory injection molding and uneven glue position caused by inaccurate positioning of the core lamination 1.

[0045] Preferably, a limiting slot 233 is provided at the lower end of the second fixed block 232, and the lower end protrusion of the core lamination contacts the limiting slot 233. The limiting slot 233 limits the displacement of the core lamination along the height direction of the second fixed block 232, so that the core lamination is fixed between the fixing part 23 and the first insert 21.

[0046] like Figures 2 to 3 As shown, the multiple gaskets of different thicknesses in this embodiment include a first gasket 6 , a second gasket 7 , a third gasket 8 and a slider gasket 9 .

[0047] The first gasket 6, the third gasket 8 and the slider gasket 9 are all provided with thin sheet type and thick sheet type, the thickness of the thick sheet type is thicker than that of the thin sheet type, and the thickness of the second gasket 7 is fixed; First shims 6, third shims 8, and slider shims 9 of varying thicknesses are combined with second shims 7 to form multiple pre-selected shim combinations. This modular and pre-set design allows the mold to quickly and accurately adjust the cavity size to accommodate varying thickness variations of the core laminations 1. This significantly simplifies the complexity of mold adaptability and avoids the high cost and time associated with customizing different mold inserts for each thickness variation.

[0048] During the injection molding process, by selecting and installing the gasket combination that best matches the thickness of the core laminations 1, the mold cavity's height and depth precisely adjust to the actual total thickness of the core laminations 1. This precise adjustment capability fundamentally eliminates injection molding defects such as excess glue, excessive glue thickness, insufficient glue, or thin glue caused by inconsistent core lamination thickness. The resulting overmolded core is free of burrs and meets acceptable appearance and dimensions. This not only significantly improves product quality and yield, but also effectively reduces material waste and subsequent processing costs caused by scrap.

[0049] like Figures 2 to 3 As shown, the specific method of installing the gasket of this embodiment is: The first gasket 6 and the second gasket 7 are arranged at the bottom of the second insert 22; Third gasket 8 is installed at the bottom of first insert 21, contacting the bottom of second gasket 7 and the bottom of core lamination 1, respectively. This gasket installation ensures precise vertical support and positioning of first insert 21 and core lamination 1 within the mold cavity. It effectively absorbs and transmits pressure from the injection molding process, preventing vertical displacement or tilting of core lamination 1, thereby ensuring the high dimensional accuracy of the overmolded core.

[0050] Slider pad 9 is positioned on the side of the slide block 5 near the front inner mold 41. This allows the slider pad 9 to fit tightly with the front inner mold 41 during mold closing, collaborating with the slide block 5 to provide lateral support and precise enclosure for the mold cavity. This is crucial for preventing horizontal deformation or flashing of the cavity during the injection molding process, further ensuring the aesthetic quality and geometric dimensions of the overmolded core.

[0051] The specific method of gasket matching in this embodiment is: a. According to the actual total thickness T of the core lamination 1 实际 The ideal total core thickness T set by the mold 理想 Thickness deviation ΔT=T 实际 -T 理想 , determine the amount of movement ΔZ that needs to be adjusted on the top surface of the first insert 21 镶件 , where ΔZ 镶件 =T 理想 -T 实际 This allows the abstract issue of uneven thickness to be transformed into a quantifiable mold adjustment target. This quantitative analysis ensures the scientific and precise nature of subsequent mold adjustments, providing a clear guide for eliminating product defects.

[0052] b. When the thickness deviation of core lamination 1 ΔT<0, T 实际 <T 理想 , resulting in ΔZ 镶件>0, the first insert 21 needs to be moved down, and in the pre-selected gasket combination, a thick first gasket 6, a thin third gasket 8 and a thin slider gasket 9 are selected, so that the total thickness change of the pre-selected gasket combination is equal to the movement amount ΔZ that the top surface of the first insert 21 needs to be adjusted. 镶件 Matching, thereby achieving a corresponding lowering of the top surface of the first insert 21; c. When the thickness deviation of the core lamination 1 is ΔT>0, T 实际 >T 理想 , resulting in ΔZ 镶件 <0, the first insert 21 needs to be moved up, and from the pre-selected gasket combination, a thin-sheet first gasket 6, a thick-sheet third gasket 8, and a thick-sheet slider gasket 9 are selected so that the total thickness change of the pre-selected gasket combination is equal to the movement amount ΔZ that the top surface of the first insert 21 needs to be adjusted. 镶件 Matching, thereby achieving a corresponding rise in the top surface of the first insert 21.

[0053] The total thickness change of the gasket combination and the movement amount ΔZ required to adjust the top surface of the first insert 21 are achieved 镶件 Precise matching. This pre-set and counter-coordinated selection and combination of shims allows for precise adjustment of the top surface height of the first insert 21, thereby varying the mold cavity dimensions. This allows the mold cavity dimensions to adapt to the actual thickness of the core laminations 1, completely eliminating injection molding defects such as excess glue, excessive glue thickness, insufficient glue, or thinness. The resulting overmolded core is free of burrs and meets all quality standards in both appearance and dimensions. This method significantly improves product qualification rates and reduces subsequent rework and material waste.

[0054] Example of shim matching method: Assume that the ideal total thickness of the core lamination 1 is T 理想 In order to adapt to the cores with different thickness deviations, the mold insert structure 2 is designed with a replaceable gasket combination.

[0055] Shim setting: First gasket 6: Thin sheet type: thickness 0.5mm; Thick sheet type: thickness is 1.0mm.

[0056] Third gasket 8: Thin sheet type: thickness 0.5mm; Thick sheet type: thickness is 1.0mm.

[0057] Slider spacer 9: Thin sheet type: thickness 0.5mm; Thick sheet type: thickness is 1.0mm.

[0058] Case 1: Iron core lamination 1 is too thin Core pre-sorting and testing: Test a batch of core laminations 1 and measure their actual total thickness T 实际 It is 29.80mm.

[0059] Calculate thickness deviation and adjustment amount: Calculate thickness deviation ΔT and the amount of movement ΔZ that needs to be adjusted on the top surface of the first insert 21 镶件 .

[0060] Thickness deviation ΔT=T 实际 -T 理想 =29.80-30.00=-0.20mm.

[0061] Movement ΔZ 镶件 =T 理想 -T 实际 =30.00-29.80=0.20mm.

[0062] Since ΔT<0, the first insert 21 needs to move downward by 0.20 mm.

[0063] Gasket matching and installation: Due to the movement ΔZ 镶件 >0, select a gasket combination that can achieve the downward movement of the insert structure 2.

[0064] Select the thick sheet type first gasket 6, Select the thin-sheet third gasket 8, Select the thin sheet type slider spacer 9.

[0065] By using this gasket combination, the top surface of the first insert 21 can be lowered by 0.20 mm, so that the mold cavity size matches the iron core with a thickness of 29.80 mm.

[0066] Case 2: Core lamination 1 is too thick Core pre-sorting and testing: Test another batch of core laminations 1 and measure their actual total thickness T 实际 It is 30.15mm.

[0067] Calculate thickness deviation and adjustment amount: Calculate thickness deviation ΔT and the amount of movement ΔZ that needs to be adjusted on the top surface of the first insert 21 镶件 .

[0068] Thickness deviation ΔT=T 实际 -T 理想 =30.15-30.00=0.15mm.

[0069] Movement ΔZ 镶件 =T 理想 -T 实际 =30.00-30.15=-0.15mm.

[0070] Since ΔT>0, the first insert 21 needs to move upward by 0.15 mm.

[0071] Gasket matching and installation: Due to the movement ΔZ 镶件 <0, select a gasket combination that can achieve upward movement of the insert structure 2.

[0072] Select the thin-sheet first gasket 6, Select the thick sheet type third gasket 8, Select thick sheet type slider spacer 9.

[0073] By using this gasket combination, the top surface of the first insert 21 can be raised by 0.15 mm, so that the mold cavity size matches the iron core with a thickness of 30.15 mm.

[0074] The core pre-classification step of this embodiment includes: sorting the core lamination sets with different thickness deviation levels from large to small according to quantity, and selecting them as priority overmolding batches for processing. This quantity-priority-based sorting and processing strategy can maximize the centralized processing of similar core laminations 1. This simplifies the frequency of replacing the gasket combination of the mold, because a larger batch of core laminations 1 can be processed after each replacement, thereby significantly improving the overall production efficiency. At the same time, by processing different batches in an orderly manner, all qualified batches of core laminations 1 can be effectively utilized, reducing the waste and scrap rate of core laminations 1 due to thickness discrepancies, and further reducing production costs.

[0075] The thickness of the core laminations 1 of this embodiment is tested after being compacted, and the compaction pressure of the core laminations 1 is equal to the holding pressure of the overmolding injection mold. When testing the thickness, the core laminations 1 are placed under conditions similar to the pressure they will withstand during the actual injection molding process for thickness measurement. Through this pre-compaction test that matches the actual injection molding conditions, more realistic and accurate final molding thickness data of the core laminations 1 can be obtained. This directly solves the problem of thickness measurement deviation caused by the failure to consider the injection molding compaction effect in traditional methods. Accurate thickness data is the basis for the subsequent precise matching of mold cavity dimensions, thereby eliminating defects such as dissatisfaction in injection molding, excess glue (burst) and other defects caused by inaccurate dimensions of the core laminations 1 from the source, and ultimately ensuring that the overmolded injection molded core has no burst, and its appearance and dimensions are qualified.

[0076] Specifically, the compaction pressure of the core lamination 1 is 50-100 MPa. In actual use, the compaction pressure is, for example, 50 MPa, 60 MPa, 70 MPa, 80 MPa, 90 MPa or 100 MPa. By setting a specific pressure range and making it consistent with the actual pressure-holding pressure, the height restorability and consistency of the core lamination 1 when measured are ensured. This standardized and simulated actual working condition measurement effectively eliminates measurement errors caused by lamination gaps, elastic deformation and other factors, thereby obtaining core thickness data closest to the actual injection molding state. This fundamentally guarantees the accuracy of subsequent mold cavity adjustment, directly eliminates injection molding defects such as overmolding, undermolding or batch edge caused by inaccurate core size, and ultimately makes the overmolding injection core batch-free, with qualified appearance and size.

[0077] The above is only a preferred embodiment of the present application. Those skilled in the art can make changes to the specific embodiments and application scope according to the idea of the present application, and the content of the specification should not be understood as a limitation of the present application.

Claims

1. A high-efficiency injection molding method for the stator and rotor cores of a motor, characterized in that: The following steps are involved: A. Core pre-classification: Classify the core laminations into sets with different thickness deviation levels according to the thickness of the core laminations (1); B. Mold structure preparation: The overmolded injection mold includes an insert structure (2), the insert structure (2) is arranged on the rear mold (3) or the front mold (4) of the mold, and the insert structure (2) is provided with multiple gaskets of different thicknesses that can adjust the size of the mold cavity. The multiple gaskets are stacked to form multiple pre-selected gasket combinations, and the gasket combinations are used to match core lamination sets with different thickness deviation levels; C. Gasket matching and installation: According to the core lamination sets with different thickness deviation levels, select and install the matching pre-selected gasket combination in the insert structure (2) to adjust the mold cavity size; D. Core loading: Position and load the core laminations (1) into the mold cavity; E. Injection molding: close the mold and perform injection molding on the core laminations (1).

2. According to the method for high-efficiency overmolding of the stator and rotor cores of a motor according to claim 1, the insert structure (2) comprises a first insert (21) and a second insert (22). The first insert (21) is provided with a cavity for accommodating the iron core laminations (1) to be overmolded; The first insert (21) is embedded inside the second insert (22); A fixing member (23) is provided in the cavity, the upper end of the fixing member (23) contacts the front mold (4), the lower end of the fixing member (23) contacts the rear mold (3), and the core lamination (1) is fixed between the fixing member (23) and the first insert (21).

3. The method for high-efficiency plastic-coating injection molding of the stator and rotor cores of a motor according to claim 2, characterized in that: The front mold (4) is provided with a front inner mold (41), and the front inner mold (41) is arranged on the inner side of the front mold (4); The rear mold (3) is provided with a rear inner mold (31) and a push plate (32), the rear inner mold (31) is provided in the rear mold (3), and the push plate (32) is provided at one end of the rear inner mold (31) close to the front inner mold (41); A sliding block (5) is provided between the front mold (4) and the rear mold (3), the upper portion of the sliding block (5) abuts against the front inner mold (41), and the lower portion of the sliding block (5) abuts against the push plate (32); The front mold (4), the front inner mold (41), the rear mold (3), the rear inner mold (31), the push plate (32) and the sliding block (5) enclose a mold cavity.

4. A high-efficiency glue-coating injection molding method for the stator and rotor core of a motor according to claim 3, wherein one end face of the sliding block (5) contacts the outer side face of the first insert (21); The inside of the rear inner mold (31) and the inner side of the push plate (32) both contact the outer side surface of the second insert (22).

5. According to the method for high-efficiency overmolding of the stator and rotor cores of a motor as described in claim 2, the fixing member (23) comprises a first fixing block (231) and a second fixing block (232), and the first fixing block (231) and the second fixing block (232) are fixed by bolts; The upper end of the first fixing block (231) contacts the front mold (4), and the lower end of the second fixing block (232) contacts the rear mold (3).

6. The method for high-efficiency plastic-coating injection molding of the stator and rotor cores of a motor according to claim 2, characterized in that: The plurality of gaskets of different thicknesses include a first gasket (6), a second gasket (7), a third gasket (8), and a slider gasket (9); The first gasket (6), the third gasket (8) and the slider gasket (9) are all provided with thin sheet type and thick sheet type, the thickness of the thick sheet type is greater than that of the thin sheet type, and the thickness of the second gasket (7) is fixed; The first gasket (6), the third gasket (8), and the slider gasket (9) of different thicknesses are combined with the second gasket (7) to form a plurality of preselected gasket combinations.

7. The method for high-efficiency plastic-coating injection molding of the stator and rotor cores of a motor according to claim 6, characterized in that: The specific method of installing the gasket is: The first gasket (6) and the second gasket (7) are arranged on the bottom of the second insert (22); The third gasket (8) is arranged at the bottom of the first insert (21) and respectively contacts the bottom of the second gasket (7) and the bottom of the core lamination (1); The slider pad (9) is arranged on a side of the sliding block (5) close to the front inner mold (41).

8. The method for high-efficiency plastic-coating injection molding of the stator and rotor cores of a motor according to claim 6, characterized in that: The specific method of gasket matching is: a. According to the actual total thickness T of the core lamination (1) 实际 The ideal total core thickness T set by the mold 理想 Thickness deviation ΔT=T 实际 -T 理想 , determine the amount of movement ΔZ that needs to be adjusted on the top surface of the first insert (21) 镶件 , where ΔZ 镶件 =T 理想 -T 实际 ; b. When the thickness deviation of the core lamination (1) ΔT < 0, T 实际 <T 理想 , resulting in ΔZ 镶件 >0, the first insert (21) needs to be moved downward, and a thick-sheet first gasket (6), a thin-sheet third gasket (8) and a thin-sheet slider gasket (9) are selected from the pre-selected gasket combination so that the total thickness change of the pre-selected gasket combination is equal to the movement amount ΔZ that needs to be adjusted on the top surface of the first insert (21) 镶件 Matching, thereby achieving a corresponding lowering of the top surface of the first insert (21); c. When the thickness deviation of the core lamination (1) ΔT>0, T 实际 >T 理想 , resulting in ΔZ 镶件 <0, the first insert (21) needs to be moved upward, and a thin-sheet first gasket (6), a thick-sheet third gasket (8) and a thick-sheet slider gasket (9) are selected from the pre-selected gasket combination so that the total thickness change of the pre-selected gasket combination is equal to the movement amount ΔZ that the top surface of the first insert (21) needs to be adjusted. 镶件 Matching, thereby achieving a corresponding rise in the top surface of the first insert (21).

9. The method for high-efficiency overmolding of the stator and rotor cores of a motor according to claim 1, characterized in that: The iron core pre-classification step includes: sorting the iron core lamination sets with different thickness deviation levels from large to small according to quantity, and selecting them as priority overmolding batches for processing.

10. The method for high-efficiency overmolding of the stator and rotor cores of a motor according to claim 1, characterized in that: The thickness of the core laminations (1) is measured after compaction, and the compaction pressure of the core laminations (1) is equal to the holding pressure of the overmolding injection mold.

Images