Manufacturing method of three-terminal plastic-coated part

Abstract

The invention relates to a manufacturing method of a three-terminal plastic-coated part, which comprises the following steps of: preparing a first material strip, preparing a second material strip, welding the material strips, performing in-mold injection molding, pre-cutting, shaking and blanking, namely welding a first connecting strip area and a second connecting strip area to form a double-layer material strip by taking a first positioning hole and a second positioning hole as a positioning basis in the material strip welding step, in the pre-cutting step, the second connecting strip is connected to the outer end of the side terminal in a single-side suspended manner; and the material shaking step enables the second connecting strip and the side terminal to be disconnected from the indentation. According to the manufacturing method, the three terminals can be helped to be accurately positioned in the plastic part, so that the precision requirement of a product is met, the process is continuous, the processing efficiency is high, the risk that the edge of the plastic part is damaged is avoided, and the quality reaches the standard.

Description

Technical Field

[0001] This invention relates to the field of electrical component technology, and in particular to a method for manufacturing a three-terminal plastic-coated part. Background Technology

[0002] Figure 1 The diagram shows a three-terminal plastic-coated component 1 with a length of only 14.4 mm. This three-terminal plastic-coated component 1 includes a symmetrical, elongated arc-shaped plastic component 11, a central terminal 12 partially covering the middle of the plastic component 11, and side terminals 13 completely covering both ends of the plastic component 11. The central terminal 12 and the two side terminals 13 are both made of conductive materials but different materials, and the plastic component 11 enables the central terminal 12 and the two side terminals 13 to maintain their relative positions.

[0003] In this three-terminal plastic-coated part 1, the dimensions of the middle terminal 12 and the side terminal 13 are only smaller, and the three terminals cannot be individually placed into the injection mold for positioning; otherwise, their relative positions cannot meet the requirements. The structure of the plastic part 11 will also be relatively fragile and prone to cracking under stress. If the relative positioning problem is solved by first molding them onto the material strip for mutual positioning and then injection molding them into the mold, another problem arises—the edge of the side terminal 13 is too close to the edge of the plastic part 11. The punching force of the side terminal 13 breaking off from the material strip will be transmitted to the plastic part 11, causing the edge of the plastic part 11 to crack, thus failing to obtain a qualified product.

[0004] Therefore, it is necessary to provide a new process to accomplish the above operations. Summary of the Invention

[0005] The main objective of this invention is to provide a manufacturing method for three-terminal plastic parts, which enables continuous processing, high processing efficiency, and avoids the risk of edge damage to plastic parts.

[0006] This invention achieves the above objective through the following technical solution: a method for manufacturing a three-terminal plastic-coated part, wherein the three-terminal plastic-coated part includes a symmetrically elongated arc-shaped plastic part, an intermediate terminal partially covering the middle portion of the plastic part, and side terminals completely covering both ends of the plastic part, wherein the intermediate terminal and the side terminals are made of different materials, and the manufacturing method includes the following steps: S1. Preparation of the first strip: The first strip is stamped out. The first strip includes an integrally connected first connecting strip area, a first connecting strip and the intermediate terminal. The first connecting strip area is provided with a first positioning hole. The intermediate terminal is connected to one side of the first connecting strip area through the first connecting strip. S2. Preparation of the second strip: The second strip is stamped out. The second strip includes an integrally connected second connecting strip area, two second connecting strips and two side terminals. The second connecting strip area is provided with a second positioning hole with the same shape as the first positioning hole. Each side terminal is connected to one side of the second connecting strip area through a second connecting strip. When the first positioning hole and the second positioning hole are aligned, the relative position of the three terminals meets the design requirements of the three-terminal plastic-coated part. The boundary position between the second connecting strip and its corresponding side terminal has an indentation that reduces the thickness. S3, Strip welding: Using the first positioning hole and the second positioning hole as positioning references, the first connecting strip area and the second connecting strip area are welded face to face to form a double-layer strip; S4. In-mold injection molding: The double-layer strip is fed into the injection mold and injection molded to form a plastic part covering the center terminal and the two side terminals, resulting in a three-terminal plastic-coated part with three points connected on the double-layer strip; S5. Pre-cutting: Using the first positioning hole and the second positioning hole as positioning references, cut off the transition area material between the two second connecting strips and the second connecting strip area. The three-terminal plastic-coated part is connected to the double-layer material strip by the first connecting strip, and the second connecting strip is connected to the outer end of the side terminal with one side suspended. S6. Shaking: Fix the height of the entire three-terminal plastic-coated part, and shake the two second connecting strips up and down until the second connecting strips are disconnected from the side terminal from the indentation. S7. Blanking: Using the first positioning hole and the second positioning hole as positioning references, cut off the connection between the first connecting strip and the three-terminal plastic-coated part, so that the three-terminal plastic-coated part is blanked.

[0007] Specifically, the connection position of the first connecting strip and the first connecting strip area is close to the first positioning hole, and the distances from the two side terminals to the second positioning hole between them are equal.

[0008] Specifically, on the same side of the first connecting strip area, there are a plurality of first bends that rise toward the side of the second material strip. The first bends are located between the first connecting strip and a second connecting strip, and the plane in which the first bends are located is along the conveying direction of the material strip.

[0009] Furthermore, on the same side of the second connecting belt area, there are several second bending portions that rise vertically away from the first material belt. All the second bending portions are coplanar with all the first bending portions and are staggered front to back.

[0010] Furthermore, one of the first connecting strip area and the second connecting strip area is provided with an alignment hole, and the other is provided with three alignment protrusions passing through the alignment hole. The three alignment protrusions are distributed in the corner points of an equilateral triangle and are all in close contact with the inner wall of the alignment hole.

[0011] Specifically, the two second connecting strips of the front and rear processing units are 0-5mm apart. When the material is shaken, the two second connecting strips are clamped and shaken off simultaneously.

[0012] The beneficial effects of the technical solution of this invention are: This manufacturing method helps to accurately position the three terminals within the plastic part, thereby meeting the product's precision requirements. Moreover, the process is continuous, the processing efficiency is high, the risk of damage to the edges of the plastic part is avoided, and the quality meets the standards. Attached Figure Description

[0013] Figure 1 A three-dimensional view of a three-terminal plastic-coated component; Figure 2 An exploded view of a three-terminal plastic-coated component; Figure 3 This is a perspective view of a single processing unit in the first material strip of Example 1; Figure 4 This is a perspective view of a single processing unit in the first material strip of Example 1; Figure 5 This is a perspective view of a single processing unit of the double-layer strip in Example 1; Figure 6 This is a perspective view of a single processing unit of the double-layer strip after in-mold injection molding in Example 1; Figure 7 This is a top view of the two processing units of the pre-cut double-layer strip in Example 1; Figure 8 This is a top view of a single processing unit of a double-layer strip material in Example 1. Figure 9 This is a perspective view of a single processing unit of the double-layer strip in Example 2.

[0014] The numbers in the image represent: 1-Three-terminal plastic-coated part, 11-Plastic part, 12-Intermediate terminal, 13-Side terminal; 2-First material strip, 21-First connecting strip area, 211-First positioning hole, 212-Alignment hole, 22-First connecting strip, 23-First bending part; 3-Second strip, 31-Second connecting strip area, 311-Second positioning hole, 312-Alignment protrusion, 32-Second connecting strip, 33-Indentation, 34-Second bending part. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to specific embodiments.

[0016] Example: like Figure 1 and Figure 2 As shown, the three-terminal plastic component 1 includes a symmetrical, elongated arc-shaped plastic component 11, an intermediate terminal 12 partially covering the middle of the plastic component 11, and side terminals 13 completely covering both ends of the plastic component 11. The intermediate terminal 12 and the side terminals 13 are both made of conductive materials but different materials, and the plastic component 11 enables the intermediate terminal 12 and the two side terminals 13 to maintain their relative positions.

[0017] The present invention discloses a method for manufacturing a three-terminal plastic-coated component, used to manufacture a three-terminal plastic-coated component 1, comprising the following steps: S1. Preparation of the first strip 2: The first strip 2 is stamped out. The first strip 2 includes an integrally connected first connecting strip area 21, a first connecting strip 22, and an intermediate terminal 12. The first connecting strip area 21 is provided with a first positioning hole 211. The intermediate terminal 12 is connected to one side of the first connecting strip area 21 through the first connecting strip 22. The connection position of the first connecting strip 22 and the first connecting strip area 21 is close to the first positioning hole 211. On the same side of the first connecting strip area 21, there are several first bending portions 23 that rise vertically towards the second strip 2. The plane where the first bending portions 23 are located is along the conveying direction of the strip. Figure 3 As shown.

[0018] In subsequent operations, the intermediate terminal 12 uses the first positioning hole 211 as the reference position for movement. Therefore, in order to improve the accuracy when stopping, the intermediate terminal 12 should be as close as possible to the first positioning hole 211 while maintaining the relative distance with the first connecting strip area 21.

[0019] S2. Preparation of the second strip 3: The second strip 3 is stamped out. The second strip 3 includes an integrally connected second connecting strip area 31, two second connecting strips 32, and two side terminals 13. The second connecting strip area 31 has a second positioning hole 311 with the same shape as the first positioning hole 211. Each side terminal 13 is connected to one side of the second connecting strip area 31 through a second connecting strip 32. When the first positioning hole and the second positioning hole are aligned, the relative position of the three terminals meets the design requirements of the three-terminal plastic-coated part 1. The dividing position between the second connecting strip 32 and its corresponding side terminal 13 has an indentation 33 that reduces the thickness. The distances from the two side terminals 13 to the second positioning hole 311 between them are equal. Several second bending portions 34 that rise vertically away from the first strip 2 are provided on the same side of the second connecting strip area 31. Figure 4 As shown.

[0020] Because the intermediate terminal 12 and the side terminals 13 are made of different materials, they are manufactured using two separate strips (first strip 2 and second strip 3). The first positioning hole 211 and the second positioning hole 311 overlap. The intermediate terminal 12 is located closer to the first positioning hole 211, and the two side terminals 13 are located on either side of the intermediate terminal 12. Therefore, the second positioning hole 311 is on the axis of symmetry of the two side terminals 13. To achieve the relative positioning and continuous processing of the three terminals (one intermediate terminal 12 and two side terminals 13), the intermediate terminal 12 must be initially formed on the first strip 2, and the two side terminals 13 must be initially formed on the second strip 3. However, the two strips must be able to align with each other to achieve the final goal. In this embodiment, the two strips are positioned with each other through the first positioning hole 211 and the second positioning hole 311.

[0021] S3. Strip Welding: Using the first positioning hole 211 and the second positioning hole 311 as positioning references, the first connecting strip area 21 and the second connecting strip area 31 are welded face-to-face to form a double-layer strip. For example... Figure 5 As shown.

[0022] Before the middle terminal 12 and the side terminal 13 are injected into the mold, the positions of the three terminals should have a certain degree of stability. Therefore, welding is used to weld the first strip 2 and the second strip 3 together. Because of the positional relationship between the middle terminal 12 and the side terminal 13, the first strip 2 and the second strip 3 can only overlap at the first connecting strip area 21 and the second connecting strip area 31. Therefore, the first connecting strip area 21 and the second connecting strip area 31 are also used as the connection points for welding.

[0023] The first bend 23 is located between the first connecting strip 22 and a second connecting strip 32, and all the second bends 34 are coplanar with all the first bends 23 and staggered one after the other.

[0024] Only after the first strip 2 and the second strip 3 are welded will the first bend 23 and the second bend 34 be coplanar, both curving to the same side. The function of the first bend 23 and the second bend 34 is directional guidance, because in the strip welding process, the two strips need to be aligned and positioned in the left-right direction first. This is why the equipment has guide grooves to guide the first bend 23 and the second bend 34 to complete the alignment and positioning. The final positioning of the two strips in the front-back direction can be completed by aligning the first positioning hole 211 and the second positioning hole 311.

[0025] S4. In-mold injection molding: The double-layer strip is fed into the injection mold, and injection molding is performed to form a plastic part 11 covering the center terminal 12 and two side terminals 13, resulting in a three-terminal plastic-coated part 1 with three points connected on the double-layer strip. Figure 6 As shown.

[0026] The double-layer strip provides a positioning basis for the three terminals (the overlapping first positioning holes 211 and second positioning holes 311), so that the three terminals in the mold will be properly wrapped in the plastic part 11. If the plastic part 11 and the double-layer strip are regarded as a whole, the forming unit will present a "day" - shaped structure at this time, and the structure will be relatively stable.

[0027] S5. Pre - cutting: Taking the first positioning holes 211 and second positioning holes 311 as the positioning reference, cut off the material in the transition area between the two second connecting strips 32 and the second connecting strip area 31. The three - terminal plastic - wrapped part 1 is connected to the double - layer strip by the first connecting strip 22, and the second connecting strip 32 is connected to the outer end of the side terminal 13 in a single - side suspended manner. As Figure 7 shown.

[0028] In the three - terminal plastic - wrapped part 1, the fact that the plastic part 11 completely wraps the side terminal 13 means that the cross - section of the side terminal 13 is very close to the edge of the plastic part 11. Using the method of directly punching the edge of the side terminal 13 easily tears the adjacent edge of the plastic part 11, and thus a qualified product cannot be obtained. This poses a new problem for the blanking of the three - terminal plastic - wrapped part 1.

[0029] S6. Shaking the strip: Fix the height of the entire three - terminal plastic - wrapped part 1, and shake the two second connecting strips 32 up and down, finally making the second connecting strip 32 and the side terminal 13 break at the indentation. As Figure 8 shown.

[0030] The complete blanking is actually split into two operations: first, break the two side terminals 13, and then break the middle terminal 12. The previous operation cannot be completed in one step. Instead, some material heads need to be left on the side terminals 13 first, and then shaken off with a slight amplitude, so as to protect the edge of the plastic part 11. The reason for setting the indentation 33 in step S2 is to improve the success rate of shaking off, because the indentation 33 will reduce the connection strength at the demarcation position, which is considered for the overall technological purpose.

[0031] The positions of the two second connecting strips 32 of the front and rear processing units are 0 - 5 mm apart. When shaking the strip, the two second connecting strips 32 are clamped and shaken off simultaneously.

[0032] Although for the same processing unit, the adjacent positions of the two second connecting strips 32 are far apart, the positions of the two second connecting strips 32 of adjacent processing units are very close. Because the connection direction of the second connecting strip 32 and the side terminal 13 is along the strip conveying direction, there is no need to separate them by a large distance. Otherwise, on the one hand, it will waste the strip length, and on the other hand, it will be inconvenient to clamp the two second connecting strips 32 simultaneously when shaking the strip (if the interval is too far, it cannot be clamped by one jaw at the same time), resulting in the complication of the equipment structure.

[0033] S7. Blanking: Using the first positioning hole 211 and the second positioning hole 311 as positioning references, cut off the connection between the first connecting strip 22 and the three-terminal plastic-coated part 1, causing the three-terminal plastic-coated part 1 to be blanked. Figure 1 As shown.

[0034] The fact that the plastic part 11 partially covers the intermediate terminal 12 indicates that the cross-section of the intermediate terminal 12 is far from the edge of the plastic part 11, so there is no need to worry about damaging the edge of the plastic part 11 during the cutting. Therefore, the final blanking cut should be made on the cross-section of the intermediate terminal 12.

[0035] This manufacturing method helps to accurately position the three terminals within the plastic part 11, thereby meeting the product's precision requirements. Moreover, the process is continuous, the processing efficiency is high, and the risk of edge damage to the plastic part 1 is avoided, ensuring that the quality meets the standards.

[0036] Example 2: like Figure 9 As shown, the difference from Embodiment 1 is that: one of the first connecting strip areas 21 is provided with an alignment hole 212, and the second connecting strip area 31 is provided with three alignment protrusions 312 passing through the alignment hole 212. The three alignment protrusions 312 are distributed in the corner points of an equilateral triangle and are all in close contact with the inner wall of the alignment hole 312.

[0037] The alignment hole 212 is a round hole punched in the first connecting strip area 21, and the alignment protrusion 312 is a raised structure folded up on the inner wall of the irregular hole in the second connecting strip area 31. The cooperation between the two allows for another central positioning position between the first strip 2 and the second strip 3. Combined with the original positioning method of the first positioning hole 211 and the second positioning hole 311, good alignment accuracy can be achieved. In practical applications, the positions and directions of the alignment hole and the alignment protrusion can be interchanged.

[0038] Based on this, only one first bend 23 that curves upward toward the second material belt 3 is needed on the first connecting belt area 21 to guide the material, without the need to add more first bends 23 and second bends 34.

[0039] The above descriptions are merely some embodiments of the present invention. Those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A method for manufacturing a three-terminal plastic-coated component, the method comprising a symmetrically elongated arc-shaped plastic component, an intermediate terminal covering the middle portion of the plastic component, and side terminals covering both ends of the plastic component, characterized in that... The manufacturing process includes the following steps: S1. Preparation of the first strip: The first strip is stamped out. The first strip includes an integrally connected first connecting strip area, a first connecting strip and the intermediate terminal. The first connecting strip area is provided with a first positioning hole, and the intermediate terminal is connected to one side of the first connecting strip area. S2. Preparation of the second strip: The second strip is stamped out. The second strip includes an integrally connected second connecting strip area, two second connecting strips and two side terminals. The second connecting strip area is provided with a second positioning hole with the same shape as the first positioning hole. Each side terminal is connected to one side of the second connecting strip area through a second connecting strip. When the first positioning hole and the second positioning hole are aligned, the relative position of the three terminals meets the design requirements of the three-terminal plastic-coated part. The boundary position between the second connecting strip and its corresponding side terminal has an indentation that reduces the thickness. S3, Strip welding: Using the first positioning hole and the second positioning hole as positioning references, the first connecting strip area and the second connecting strip area are welded to form a double-layer strip; S4. In-mold injection molding: The double-layer strip is fed into the injection mold and injection molded to form a plastic part covering the center terminal and the two side terminals, resulting in a three-terminal plastic-coated part with three points connected on the double-layer strip; S5. Pre-cutting: Using the first positioning hole and the second positioning hole as positioning references, cut off the transition area material between the two second connecting strips and the second connecting strip area. The three-terminal plastic-coated part is connected to the double-layer material strip by the first connecting strip, and the second connecting strip is connected to the outer end of the side terminal with one side suspended. S6. Shaking: Fix the height of the entire three-terminal plastic-coated part, and shake the two second connecting strips up and down until the second connecting strips are disconnected from the side terminal from the indentation. S7. Blanking: Using the first positioning hole and the second positioning hole as positioning references, cut off the connection between the first connecting strip and the three-terminal plastic-coated part, so that the three-terminal plastic-coated part is blanked.

2. The manufacturing method of the three-terminal plastic-coated part according to claim 1, characterized in that: The connection position of the intermediate terminal to the first connecting strip area is close to the first positioning hole, and the distances from the two side terminals to the second positioning hole between them are equal.

3. The manufacturing method of the three-terminal plastic-coated part according to claim 1, characterized in that: On the same side of the first connecting strip area, there are a plurality of first bends that rise toward the side closer to the second material strip. The first bends are located between the first connecting strip and a second connecting strip, and the plane in which the first bends are located is along the conveying direction of the material strip.

4. The manufacturing method of the three-terminal plastic-coated part according to claim 3, characterized in that: On the same side of the second connecting belt area, there are several second bending portions that rise vertically away from the first material belt. All the second bending portions are coplanar with all the first bending portions and are staggered front to back.

5. The manufacturing method of the three-terminal plastic-coated part according to claim 1 or 3, characterized in that: One of the first connecting strip area and the second connecting strip area is provided with an alignment hole, and the other is provided with three alignment protrusions passing through the alignment hole. The three alignment protrusions are distributed in the corner points of an equilateral triangle and are all in close contact with the inner wall of the alignment hole.

6. The manufacturing method of the three-terminal plastic-coated part according to claim 1, characterized in that: The two second connecting bars of the front and rear processing units are 0-5mm apart. When the material is shaken, the two second connecting bars are clamped and broken at the same time.

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