A self-adhesive rivet-free iron core and its production process

Abstract

The invention relates to the technical field of iron core production, and in particular to a self-adhesive iron core without rivets and a production process thereof, comprising the following steps: pre-determining the position of a silicon steel sheet on a steel strip with a self-adhesive coating; punching the outer side of the silicon steel sheet to form a silicon steel sheet and two frames; performing half-shear punching on the connection between the silicon steel sheet and the frame to make the silicon steel sheet punch out a certain distance from the frame; shaping to make the silicon steel sheet and the frame be in the same plane; cutting the steel strip to make the silicon steel sheet and the frame form a separate sheet body; stacking a plurality of sheets together, punching out buckle points on the frame, and riveting them into a whole through the buckle points; heating the plurality of sheets to melt the self-adhesive coating, cooling the sheets to solidify the self-adhesive coating and fix the stacked plurality of silicon steel sheets together; fixing the silicon steel sheet, separating the frame from the silicon steel sheet, and obtaining an iron core unit; arranging a plurality of iron core sub-units along the circumferential direction, and clamping adjacent iron core units to form a complete iron core.

Description

Technical Field

[0001] The invention relates to the technical field of tooling, and in particular to a self-adhesive rivet-free iron core and a production process thereof. Background Art

[0002] The iron core is the central part of the motor, which is composed of multiple stamped silicon steel sheets. Usually, the connection methods of iron core products are buckle points, welding, rivets, glue bonding, etc. Among them, buckle points and rivets destroy the integrity of product design, thus affecting product performance. Although the welding method does not destroy the integrity of the product, it is generally welded by combining single pieces. The product quality is restricted by the accuracy of the piece handling tooling and has low efficiency. The glue method also ensures the integrity of the product, but because the glue process itself is not mature and the unit price is expensive, it is not suitable for long-term mass production.

[0003] For this purpose, a method of injection molding outside the silicon steel sheet was designed to achieve a rivet-free core. However, in order not to affect the subsequent assembly and use of the core, injection molding can only be performed on a part of the side wall of the silicon steel sheet, which results in insufficient connection strength between the silicon steel sheets inside the plastic. Summary of the invention

[0004] The technical problem to be solved by the present invention is: in order to solve the technical problems in the prior art, the present invention provides a production process for a self-adhesive rivet-free iron core.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a production process of a self-adhesive rivet-free iron core, comprising the following steps:

[0006] S1. Use a steel strip with a self-adhesive coating and pre-determine the position of the silicon steel sheet on the steel strip;

[0007] S2. Punching is performed on the outer side of the silicon steel sheet to remove part of the waste material, so that part of the outer contour of the silicon steel sheet is exposed, and the remaining waste material on the steel strip is formed into two frames connecting the silicon steel sheets, and the two frames are located on both sides of the silicon steel sheet;

[0008] S3, perform half-shear punching on the connection between the silicon steel sheet and the frame, so that the silicon steel sheet is punched out of the frame by a certain distance;

[0009] S4, shaping to make the silicon steel sheet and the frame in the same plane;

[0010] S5, cutting the steel strip to form a separate sheet from the silicon steel sheet and the frame;

[0011] S6. Stack multiple sheets together, punch out buckle points on the frame, and rivet them together into a whole through the buckle points;

[0012] S7, heating the multiple sheets to melt the self-adhesive coating, connecting adjacent silicon steel sheets through the melted self-adhesive coating material, and then cooling the sheets to solidify the self-adhesive coating, thereby finally connecting the silicon steel sheets into one;

[0013] S8, separating the silicon steel sheet from the frame to obtain an iron core subunit;

[0014] S9, arranging a plurality of core sub-units along the circumferential direction, and clamping adjacent core sub-units together to form a complete core.

[0015] The self-adhesive rivet-free iron core production process of the present invention adopts a steel strip with a self-adhesive coating. After multiple sheets are stacked, the multiple sheets are heated to melt the self-adhesive coating, and then the multiple sheets are cooled to solidify the self-adhesive coating again, thereby connecting adjacent silicon steel sheets together. Compared with injection molding, the bonding area between the silicon steel sheets connected by the self-adhesive coating is larger and the fit is tighter, so the connection strength is more reliable.

[0016] Further, in S7, the sheet is heated and cooled by the subsequent equipment. The sheet is first placed in an environment of 180-220 degrees Celsius and under pressure for one cycle. Then, the sheet is placed in an environment of 0 degrees Celsius and under pressure for another cycle.

[0017] Furthermore, the one cycle is 1-3 minutes.

[0018] Further, in S7, the sheet is heated by an oven, and the sheet is placed in the oven and maintained at a temperature of 100 to 180 degrees Celsius for 1 hour.

[0019] Further, in step S8, the silicon steel sheets are firstly injection molded so that the plurality of silicon steel sheets form a whole, and then the silicon steel sheets are separated from the frame to obtain the iron core sub-unit.

[0020] Furthermore, the back-end equipment includes an upper mold frame and a lower mold frame, the lower mold frame is provided with a heating component and a cooling component, the upper mold frame is provided with a pressing component, and the pressing component has two pressing rods, which respectively extend into the heating component and the cooling component to press the silicon steel sheet.

[0021] Furthermore, the heating assembly includes a die and a heating coil, the die is mounted on a lower die frame, a heating groove for accommodating the sheet is provided in the die, and the heating coil is arranged around the side wall of the heating groove.

[0022] Furthermore, the cooling assembly includes a cooling tray and a cooling side plate, the cooling tray is installed on the lower mold frame, the cooling tray is used to place the sheet body, the cooling side plate is installed on the cooling tray, and the cooling side plate is arranged around the circumference of the cooling support plate to form a cooling groove for accommodating the sheet body.

[0023] Furthermore, the lower mold frame is provided with a first limiting column, and the upper mold frame is provided with a second limiting column. When the upper mold frame and the lower mold frame are closed, the first limiting column abuts against the second limiting column.

[0024] Furthermore, two ejector rods are provided in the lower mold frame, and the two ejector rods are respectively located below the heating groove and the cooling groove so as to lift the sheet body. The two ejector rods are connected to the same linkage plate, and the ejector rods are threadedly connected to the linkage plate.

[0025] The beneficial effects of the present invention are:

[0026] 1. By using a steel strip with a self-adhesive coating, after stacking multiple sheets, the multiple sheets are heated to melt the self-adhesive coating, and then the multiple sheets are cooled to solidify the self-adhesive coating again, thereby connecting adjacent silicon steel sheets together. Compared with injection molding, the bonding area between the silicon steel sheets connected by the self-adhesive coating is larger, the fit is tighter, and the connection strength is more reliable;

[0027] 2. By keeping multiple silicon steel sheets under pressure for heating and cooling, the close fit of adjacent silicon steel sheets and the connection strength between adjacent silicon steel sheets can be ensured;

[0028] 3. Through the setting of the linkage plate and the ejector rod, it is convenient to eject the sheets in the heating tank and the cooling tank at the same time, saving costs. At the same time, the ejector rod is threadedly connected to the linkage plate, which is convenient for adjusting the height of the ejector rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0030] Figure 1 It is a schematic structural diagram of a sheet body formed by a frame and silicon steel sheets in the present invention.

[0031] Figure 2 It is a schematic diagram of a silicon steel sheet in the present invention.

[0032] Figure 3 It is a schematic diagram of the framework in the present invention.

[0033] Figure 4 It is a schematic diagram of the back-end equipment in the present invention.

[0034] Figure 5It is a schematic diagram of the upper pressing plate and the lower pressing plate in the present invention.

[0035] Figure 6 It is a schematic diagram of the internal heating plate in the present invention.

[0036] In the figure: 1. frame; 12. first clamping surface; 121. connecting groove; 16. buckle point; 2. silicon steel sheet; 23. first connecting surface; 231. connecting protrusion; 3. upper mold frame; 31. pressure rod; 311. upper pressure plate; 312. lower pressure plate; 313. adjusting bolt; 314. compression spring; 315. countersunk hole; 32. second limiting column; 4. lower mold frame; 41. heating component; 411. die; 412. heating coil; 413. heating trough; 414. inner heating plate; 42. cooling component; 421. cooling tray; 422. cooling side plate; 423. cooling trough; 424. cooling pipe; 43. first limiting column; 44. ejector rod; 45. linkage plate. DETAILED DESCRIPTION

[0037] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0038] In the description of the present invention, it should 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 indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" 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 it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] The invention discloses a production process for a self-adhesive iron core without rivets.

[0040] Reference Figure 1 and Figure 2 A self-adhesive rivet-free core production process comprises the following steps:

[0041] S1. Use a steel strip with a self-adhesive coating and predetermine the position of the silicon steel sheet 2 on the steel strip. The steel strip can be made of Shanghai Baosteel steel, and the model can be B25A230Z, B35A300Z, or B20.

[0042] S2. Punching is performed on the outer side of the silicon steel sheet 2 to remove part of the waste material, so that part of the outer contour of the silicon steel sheet 2 is exposed, and the remaining waste material on the steel strip is formed into two frames 1 connecting the silicon steel sheet 2, and the two frames 1 are located on both sides of the silicon steel sheet 2. Figures 1 to 3 , both sides of the silicon steel sheet 2 are provided with a first clamping surface 12, and the two frames 1 are provided with a first connecting surface 23 that matches the first clamping surface 12. The first connecting surface 23 is provided with a connecting groove 121, and the first clamping surface 12 is provided with a connecting protrusion 231 that matches the connecting groove 121. The silicon steel sheet 2 is provided with multiple pieces along the length direction of the frame 1, and in this embodiment, there are three pieces.

[0043] S3. Perform half-shear punching on the connection between the silicon steel sheet 2 and the frame 1 to make the silicon steel sheet 2 punch out of the frame 1 by a certain distance.

[0044] S4. Perform shaping so that the silicon steel sheet 2 and the frame 1 are in the same plane.

[0045] S5. Cut the steel strip to form the silicon steel sheet 2 and the frame 1 into a separate sheet.

[0046] S6. Stack a plurality of sheets together, punch out buckle points 16 on the frame 1, and rivet them together into a whole through the buckle points 16.

[0047] S7. Heat the multiple sheets to melt the self-adhesive coating, connect the adjacent silicon steel sheets 2 through the melted self-adhesive coating material, and then cool the sheets to solidify the self-adhesive coating, and finally connect the silicon steel sheets 2 as a whole. During heating, the sheets are heated and cooled by the subsequent equipment, and the multiple sheets stacked together are first placed in an environment of 180-220 degrees Celsius by the subsequent equipment, and the multiple sheets stacked together are placed in a compressed state. After maintaining one cycle, the sheets are placed in an environment of 0 degrees Celsius, maintained in a compressed state, and maintained for another cycle. One cycle is 1-3 minutes, and in this embodiment is 1 minute. Keeping the multiple sheets in a compressed state during heating and cooling is convenient for ensuring the control of the product's behavioral tolerance during the curing process.

[0048] In another embodiment, the sheet is not under pressure when the sheet is heated; the sheet is only under pressure when the sheet is cooled.

[0049] Reference Figures 4 to 6 The back-end equipment includes an upper mold frame 3 and a lower mold frame 4. The lower mold frame 4 is provided with a heating component 41 and a cooling component 42. The upper mold frame 3 is provided with a pressing component. The pressing components can be two groups or one group. When the pressing components are two groups, the two groups of pressing components correspond to the heating component 41 and the cooling component 42 respectively. When the pressing components are one group, they only correspond to the cooling component 42. The pressing component includes a pressing rod 31 and a pressing piece connected to the pressing rod 31. The pressing piece is used to extend into the cooling component 42 and press the silicon steel sheet 2. The top of the pressing rod 31 is fixedly connected to the upper mold frame 3 to move synchronously with the upper mold frame 3.

[0050] The pressing member includes an upper pressing plate 311, an elastic member and a lower pressing plate 312. The upper pressing plate 311 is fixedly connected to the bottom of the pressing rod 31. The elastic member is arranged between the upper pressing plate 311 and the lower pressing plate 312. The upper pressing plate 311 and the lower pressing plate 312 are connected by an adjusting bolt 313. The head of the adjusting bolt 313 passes through the upper pressing plate 311 and is threadedly connected to the lower pressing plate 312, so that the adjusting bolt 313 can not only connect the upper pressing plate 311 and the lower pressing plate 312, but also adjust the distance between the upper pressing plate 311 and the lower pressing plate 312. The elastic member can be a compression spring 314, which is sleeved on the adjusting bolt 313. A countersunk hole 315 is provided at the bottom of the upper pressing plate 311 to accommodate the compression spring 314. The lower pressure plate 312 is used to contact the top surface of the sheet body. When the pressing rod is pressed down, the lower pressure plate 312 first contacts the top surface of the sheet body. At this time, the pressing rod continues to press down, so that the compression spring 314 is compressed until the upper pressure plate 311 contacts the lower pressure plate 312. That is, the pressure applied by the sheet body is provided by the compression spring 314, which in turn provides a stable and controllable pressure to the sheet body. At the same time, the distance between the upper pressure plate 311 and the lower pressure plate 312 can be adjusted by adjusting the bolt 313, thereby adjusting the pressure applied by the lower pressure plate 312 on the sheet body.

[0051] Specifically, the heating assembly 41 includes a die 411 and a heating coil 412. The die 411 is mounted on the lower mold frame 4. A heating groove 413 for accommodating the sheet is provided in the die 411. The heating coil 412 is arranged around the side wall of the die 411 so as to evenly heat the sheet. A spiral groove is provided on the side wall of the die 411 in the vertical direction. The heating coil 412 is at least partially located in the spiral groove and fits with the groove wall of the spiral groove to increase the contact area between the heating coil 412 and the die 411, thereby improving the heat transfer effect. The use of the heating coil 412 for heating can improve the heating effect, and at the same time, it is convenient to install a temperature sensor in the heating groove 413, and the temperature in the heating groove 413 can be accurately controlled by the temperature control system of the heating system. The heating of the sheet needs to be strictly controlled. If it is overheated, it may cause glue overflow. If the temperature is too low or the time is too short, the bonding strength between adjacent silicon steel sheets 2 may be insufficient.

[0052] In another embodiment, an inner heating plate 414 is connected to the bottom surface of the heating groove 413, and the inner heating plate 414 is used to be inserted into the sheet body, thereby facilitating the heating effect on the silicon steel sheet. The shape of the inner heating plate 414 can fit the inner side of the exterior and the outer side of the silicon steel sheet.

[0053] More specifically, the cooling assembly 42 includes a cooling tray 421 and a cooling side plate 422. The cooling tray 421 is mounted on the lower mold frame 4. The cooling tray 421 is used to place the sheet. The cooling side plate 422 is mounted on the cooling tray 421. The cooling side plate 422 is arranged around the circumference of the cooling tray to form a cooling groove 423 for accommodating the sheet. A cooling pipe 424 is spirally wound on the side wall of the cooling side plate 422. The cooling pipe 424 is connected to a cooling device. The cooling device provides cooling water to the cooling pipe to achieve circulating cooling, thereby facilitating the control of the cooling temperature. The cooling device can be a refrigerator. The cooling pipe 424 can be a flat copper tube. Compared with a round copper tube, the contact area between the flat copper tube and the cooling side plate 422 is larger, and the cooling effect is better.

[0054] The lower mold frame 4 is connected to a first limiting column 43 , and the upper mold frame 3 is connected to a second limiting column 32 . When the upper mold frame 3 and the lower mold frame 4 are closed, the first limiting column 43 abuts against the second limiting column 32 , thereby facilitating the control of the distance between the upper mold frame 3 and the lower mold frame 4 .

[0055] In order to facilitate ejection of the sheet, two ejector rods 44 are vertically provided in the lower mold frame 4. The two ejector rods 44 are respectively located below the heating groove 413 and the cooling groove 423 to lift the sheet. The bottoms of the two ejector rods 44 are connected to the same linkage plate 45, so that the linkage plate can simultaneously drive the two ejector rods 44 to work. The two ejector rods 44 are respectively threadedly connected to the linkage plate 45 to adjust the height of the ejector rods 44.

[0056] It should be noted that when the inner heating plate 414 is connected to the bottom surface of the heating groove 413 , the ejector rod 44 is configured as a hollow rod structure to avoid interference with the inner heating plate 414 .

[0057] During operation, by controlling the heating coil 412 and the cooling device, the time required for heating and cooling of the sheet is the same, so that the heating component 41 and the cooling component 42 can share a set of presses, and synchronous material discharge and discharging can also be achieved, saving costs and improving efficiency. After the two groups of sheets are placed in the heating groove 413 and the cooling groove 423 respectively, the upper mold frame 3 moves down, so that the two pressure rods 31 extend into the heating groove 413 and the cooling groove 423 respectively, and press the two groups of sheets, so that the two groups of sheets are in a compressed state.

[0058] In another embodiment, the sheet can also be heated by an oven, and the sheet is placed in the oven and kept at a temperature of 100 to 180 degrees Celsius for 1 hour. The advantage is that a common oven can be used without additional modification, and the cost is low; however, the common oven has a poor heating effect on the sheet, and it is not convenient to keep multiple sheets under pressure, and a separate cooling component 42 is also required.

[0059] S8, separate the silicon steel sheet 2 from the frame 1 to obtain the iron core subunit. After the silicon steel sheet 2 is bonded by the self-adhesive coating, the strength of the silicon steel sheet 2 is sufficient, so the silicon steel sheet 2 can continue to be injection molded, or it can be no longer injection molded. If injection molding is required, after the self-adhesive coating is cured, the silicon steel sheet 2 is first injection molded so that multiple silicon steel sheets 2 form an integral injection molded part, and then the silicon steel sheet 2 is separated from the frame 1 to obtain the iron core subunit.

[0060] In addition, the self-adhesive coating connection method has simpler equipment and lower costs compared to injection molding.

[0061] S9, arranging a plurality of core sub-units along the circumferential direction, and clamping adjacent core sub-units together to form a complete core.

[0062] Working principle: By using a steel strip with a self-adhesive coating, after multiple sheets are stacked, the multiple sheets are heated to melt the self-adhesive coating, and then the multiple sheets are cooled to solidify the self-adhesive coating again, thereby connecting adjacent silicon steel sheets 2 together. Compared with injection molding, the bonding area between the silicon steel sheets 2 connected by the self-adhesive coating is larger and the fit is tighter, so the connection strength is more reliable.

[0063] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A process for producing a self-adhesive rivet-free iron core, characterized in that: The steps include: S1, using a steel strip with a self-adhesive coating, and pre-determining the position of the silicon steel sheet (2) on the steel strip; S2, punching the outer side of the silicon steel sheet (2) to remove part of the waste material, so that a part of the outer contour of the silicon steel sheet (2) is exposed, and the remaining waste material on the steel strip is formed into two frames (1) connecting the silicon steel sheet (2), and the two frames (1) are located on both sides of the silicon steel sheet (2); S3, performing half-shear punching on the connection between the silicon steel sheet (2) and the frame (1), so that the silicon steel sheet (2) is punched out of the frame (1) by a certain distance; S4, shaping so that the silicon steel sheet (2) and the frame (1) are in the same plane; S5, cutting the steel strip so that the silicon steel sheet (2) and the frame (1) form a separate sheet; S6, stacking the multiple sheets together, punching out buckle points (16) on the frame (1), and riveting them together into a whole through the buckle points (16); S7, heating the plurality of sheets to melt the self-adhesive coating, connecting adjacent silicon steel sheets (2) through the melted self-adhesive coating material, and then cooling the sheets to solidify the self-adhesive coating, thereby finally connecting the silicon steel sheets (2) into one body; The sheet is heated and cooled by the back-end equipment, and the sheet is first placed in an environment of 180 to 220 degrees Celsius by the back-end equipment, and maintained for a cycle, and then placed in an environment of 0 degrees Celsius, kept under pressure, and maintained for another cycle, wherein one cycle is 1 to 3 minutes; The post-process equipment comprises an upper mold frame (3) and a lower mold frame (4), the lower mold frame (4) is provided with a heating component (41) and a cooling component (42), the upper mold frame (3) is provided with a pressing component, the pressing component comprises a pressing rod (31) and a pressing piece connected to the pressing rod (31), the pressing piece is used to extend into the cooling component (42) and press the silicon steel sheet (2), the top of the pressing rod (31) is fixedly connected to the upper mold frame (3) so as to move synchronously with the upper mold frame (3); The pressing member comprises an upper pressing plate (311), an elastic member and a lower pressing plate (312); the upper pressing plate (311) is connected to the bottom of the pressing rod (31); the elastic member is arranged between the upper pressing plate (311) and the lower pressing plate (312); the upper pressing plate (311) and the lower pressing plate (312) are connected via an adjusting bolt (313); the head of the adjusting bolt (313) passes through the upper pressing plate (311) and is threadedly connected to the lower pressing plate (312), so that the adjusting bolt (313) can not only connect the upper pressing plate (311) and the lower pressing plate (312), but also adjust the distance between the upper pressing plate (311) and the lower pressing plate (312); S8, separating the silicon steel sheet (2) and the frame (1) to obtain an iron core subunit; S9, arranging a plurality of core sub-units along the circumferential direction, and clamping adjacent core sub-units together to form a complete core.

2. The process for producing a self-adhesive rivet-free iron core according to claim 1, characterized in that: In S7, the sheet is heated in an oven, and the sheet is placed in the oven at a temperature of 100 to 180 degrees Celsius for 1 hour.

3. The process for producing a self-adhesive rivet-free iron core according to claim 1, characterized in that: In step S8, the silicon steel sheets (2) are first injection molded so that the plurality of silicon steel sheets (2) form a whole, and then the silicon steel sheets (2) and the frame (1) are separated to obtain an iron core subunit.

4. The process for producing a self-adhesive rivet-free iron core according to claim 1, characterized in that: The heating assembly (41) comprises a concave mold (411) and a heating coil (412); the concave mold (411) is mounted on a lower mold frame (4); a heating groove (413) for accommodating a sheet is provided in the concave mold (411); and the heating coil (412) is arranged around the side wall of the heating groove (413).

5. The process for producing a self-adhesive rivet-free iron core according to claim 4, characterized in that: The cooling assembly (42) includes a cooling tray (421) and a cooling side plate (422), wherein the cooling tray (421) is mounted on the lower mold frame (4), the cooling tray (421) is used to place the sheet body, and the cooling side plate (422) is mounted on the cooling tray (421), and the cooling side plate (422) is arranged around the circumference of the cooling support plate to form a cooling groove (423) for accommodating the sheet body.

6. The process for producing a self-adhesive rivet-free iron core according to claim 5, characterized in that: The lower mold frame (4) is provided with a first limiting column (43), and the upper mold frame (3) is provided with a second limiting column (32). When the upper mold frame (3) and the lower mold frame (4) are closed, the first limiting column (43) abuts against the second limiting column (32).

7. The process for producing a self-adhesive rivet-free iron core according to claim 6, characterized in that: Two ejector rods (44) are arranged in the lower mold frame (4), and the two ejector rods (44) are respectively located below the heating groove (413) and the cooling groove (423) so as to lift the sheet body, and the two ejector rods (44) are connected to the same linkage plate (45), and the ejector rods (44) are threadedly connected to the linkage plate (45).

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