A precision stamping die, forming process, and the resulting metal part

Abstract

This invention discloses a precision stamping die, a forming process, and the resulting metal part, relating to the field of precision stamping technology for metal parts. The key technical points are: it includes a lower die base, a support base, a force transmission block, and an upper die assembly. The support base is fixed to the lower die base and has a gradually expanding opening slot. Rotating slots are provided on both sides of the bottom of the opening slot. Two rotary forming parts are symmetrically arranged within the opening slot, with their bottom rotating parts rotatably connected to the rotating slots. A first elastic element is located within the support base, allowing the top of the rotary forming parts to open naturally. The force transmission block slides longitudinally on the lower die base, with a metal blank placed on its top and its bottom connected to the lower die base via a second elastic element. The upper die assembly includes a first pressing rod, which, when descending, presses against the blank, driving the force transmission block downwards. The force transmission block drives the two rotary forming parts to rotate in opposite directions, thereby forming the sidewall of the metal blank in a forward direction, effectively avoiding the problems of metal wires and product defects caused by traditional lateral friction forming methods.

Description

Technical Field

[0001] This invention relates to the field of precision stamping technology for metal parts, and more specifically, to a precision stamping die, a forming process, and the resulting metal parts. Background Technology

[0002] In the field of metal plastic forming technology, for precision metal parts (such as various connector terminals and precision connectors) requiring high dimensional accuracy, high mechanical strength, and high surface integrity, the sidewall forming quality directly determines the final performance, reliability, and safety of the product. Currently, the sidewalls of such metal parts are mainly formed using stamping dies. Traditional stamping dies, such as... Figure 7 As shown, it mainly includes two longitudinally movable side-pressure forming parts 12. During operation, the forming force applied by the two side-pressure forming parts 12 to the metal blank is essentially a lateral frictional force acting at a fixed point, with a tangential component in the direction of the contact surface.

[0003] In the above-described process, at the instant the mold closes and the side-pressed forming part 12 contacts the initial line of the blank, excessive lateral frictional shear force directly scrapes the surface grain structure of the metal blank, thereby generating metal wires. These metal wires not only lead to poor product appearance, but may also cause serious risks such as decreased electrical contact performance, insulation failure, and even short circuits, severely affecting the reliability and safety of the product. This problem has been a technical bottleneck that has plagued the industry for many years and affected the mass production qualification rate.

[0004] Therefore, a new solution is needed to address this problem. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a precision stamping die, a forming process and a metal part produced therefrom, which can perform forward forming of the sidewall of a metal blank, effectively avoiding the problems of metal wires and product defects caused by the traditional side friction forming method.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: a precision stamping die, comprising:

[0007] Lower mold base;

[0008] A support base is fixed on the lower mold base. The support base has an opening groove with a gradually expanding opening. Rotating grooves are provided on both sides of the bottom of the opening groove.

[0009] Two rotary forming parts are symmetrically arranged in the opening slot. Each rotary forming part has a rotating part on the opposite side of its bottom. The rotating part is rotatably connected to the corresponding rotating slot. A driving slot is provided between the two rotary forming parts.

[0010] The first elastic element is disposed in the support base and acts on the bottom of the two rotary forming parts to push the two rotary forming parts upward, so that the tops of the two rotary forming parts open outward in their natural state.

[0011] The force transmission block is longitudinally slidably disposed on the lower mold base and partially located in the drive groove. The top of the force transmission block is used to place and support the metal billet, and the bottom is connected to the lower mold base through a second elastic element.

[0012] The upper mold assembly includes a first pressing rod. When the first pressing rod moves downward, it can press against the metal blank and drive the force transmission block to move downward. The bottom of the portion of the force transmission block located in the driving groove presses against the bottom of the driving groove, thereby driving the two rotary forming parts to rotate and close towards each other around their respective rotating parts to form the sidewall of the metal blank.

[0013] Preferably, the upper mold assembly further includes an upper mold base, the first pressing rod is longitudinally slidably connected to the upper mold base, and a third elastic element is provided between the first pressing rod and the upper mold base so that the first pressing rod has a downward pre-pressing stroke relative to the upper mold base.

[0014] Preferably, the elastic force of the third elastic element is greater than that of the second elastic element.

[0015] Preferably, the upper mold assembly further includes a second pressing rod, which is fixedly connected to the upper mold base and located directly above the two rotationally formed parts;

[0016] Before the upper mold assembly moves downward, the downward stroke of the first pressing rod is greater than that of the second pressing rod.

[0017] After the first pressing rod drives the rotary forming component to complete the sidewall forming of the metal blank, as the upper mold assembly continues to descend, the second pressing rod presses against the top of the two rotary forming components.

[0018] Preferably, the rotating part is a cylindrical rotating shaft, and the rotating groove is an arc-shaped groove that matches the rotating shaft.

[0019] Preferably, the first elastic element includes a first spring and a push head. The support base has a push groove communicating with the opening slot. The push head is slidably connected in the push groove. The first spring is supported between the push head and the lower mold base, and the top of the push head abuts against the bottom of the two rotationally formed parts.

[0020] Preferably, a shaping groove is provided on the lower end surface of the second pressing rod to accommodate and shape the top of the metal billet.

[0021] Preferably, the portion of the force transmission block located within the drive groove is a force transmission arm extending outward from the side wall of the force transmission block.

[0022] A precision stamping forming process, employing any of the aforementioned precision stamping forming dies, the precision stamping forming process comprising the following steps:

[0023] S1. Place the metal billet on top of the force transmission block;

[0024] S2. Drive the upper mold assembly downward so that the first pressing rod presses against the metal billet;

[0025] S3. The upper mold assembly continues to descend, and the force transmission block carries the metal billet down together under the drive of the first pressing rod;

[0026] S4. During the downward movement of the force transmission block, the bottom of the portion of the force transmission block located in the driving groove presses against the bottom of the driving groove, thereby driving the two rotary forming parts to rotate and close towards each other around their respective rotating parts.

[0027] S5. During the rotational closing process of the two rotary forming parts, the inner sides of the two rotary forming parts start from line contact with the sidewall of the metal blank and gradually change to surface contact, so as to perform positive forming on the sidewall of the metal blank.

[0028] A metal component, wherein the metal component is manufactured using any of the precision stamping molds or the precision stamping process described above, and no metal wires are generated on the sidewall of the metal component.

[0029] Compared with existing technologies, the advantages of the precision stamping die and forming process disclosed in this invention are as follows: By setting two rotating forming parts with rotating parts at their bottoms, and coordinating with the longitudinal movement of the force transmission block, the lateral frictional force on the fixed point of the metal blank in the traditional process is transformed into a positive forming force with continuously changing contact points applied by the rotating forming parts to the sidewall of the metal blank. During the forming process, the inner side of the rotating forming part and the sidewall of the metal blank start from line contact and gradually become surface contact as they rotate and close. The direction of the force is always perpendicular to the tangent of the contact point, effectively avoiding the scraping of the metal surface by traditional lateral sliding friction, thereby eliminating the generation of metal wires and effectively improving the forming quality, overall performance, and production stability of the metal parts. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of a precision stamping die according to an embodiment of this application;

[0032] Figure 2 This is an exploded view of a precision stamping die according to an embodiment of this application;

[0033] Figure 3 This is a schematic diagram of the precision stamping die in the open state according to an embodiment of this application;

[0034] Figure 4 This is a schematic diagram of the precision stamping die in the closed state according to an embodiment of this application;

[0035] Figure 5 This is a cross-sectional view of the force transmission block according to an embodiment of this application;

[0036] Figure 6 This is a schematic diagram of the structure of the third elastic element in an embodiment of this application;

[0037] Figure 7 This is a schematic diagram of the structure of a stamping die used for metal parts in a traditional manner.

[0038] The numbers or letters in the attached diagram represent the names of the corresponding components:

[0039] 1. Support base; 1a. Opening slot; 1b. Rotating slot; 1c. Pushing slot; 2. Rotational forming part; 21. Rotating part; 22. Drive slot; 3. Force transmission block; 31. Force transmission arm; 4. First pressing rod; 5. Second pressing rod; 6. First elastic element; 61. Pushing head; 62. First spring; 8. Lower mold base; 9. Second elastic element; 91. Second spring; 92. First guide post; 10. Third elastic element; 101. Third spring; 102. Second guide post; 103. Limiting block; 11. Upper mold base; 12. Side-pressed forming part. Detailed Implementation

[0040] The technical solution of the present invention will now be clearly and completely described through specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0041] Please see also Figures 1 to 6 This application provides a precision stamping die for mounting on a stamping press to forward-form the sidewalls of a metal blank to produce a metal part with no metal wires on the sidewalls. In this embodiment, the metal part is an automotive connector terminal. The die includes a lower die base 8, a support base 1, two rotary forming parts 2, a first elastic element 6, a force transmission block 3, and an upper die assembly.

[0042] The support base 1 is fixed to the lower die base 8 by bolts. The lower die base 8 is fixed to the worktable of the stamping machine by bolts or clamps. The support base 1 has an opening groove 1a with a gradually expanding opening. That is, the side wall of the opening groove 1a slopes outward continuously from the bottom to the top, and its cross-section is a "trumpet mouth" shaped structure with a larger top and a smaller bottom. This setting provides adaptive space for the rotation and opening of the rotationally formed part 2. Rotation grooves 1b are respectively provided on the inner walls of the bottom two sides of the opening groove 1a. In this embodiment, the rotation groove 1b is preferably an arc-shaped groove.

[0043] Two rotary molded parts 2 are symmetrically arranged in the opening groove 1a. Each rotary molded part 2 has a rotating part 21, preferably a cylindrical rotating shaft, on its opposite bottom side, which is adapted to fit an arc-shaped groove. The two rotary molded parts 2 are rotatably connected to corresponding rotating grooves 1b via their rotating parts 21, allowing them to rotate around the axis of the rotating part 21. In a preferred embodiment, the rotation angle of the rotary molded parts is 2 degrees. A driving groove 22 is provided between the opposing inner surfaces of the two rotary molded parts 2. This driving groove 22 is formed by L-shaped slots respectively formed on each rotary molded part 2. To allow the tops of the two rotary molded parts 2 to automatically open outwards in their natural state (i.e., the mold-opening state), a first elastic member 6 is provided in the support base 1. This first elastic member 6 acts on the bottom of the two rotary molded parts 2, continuously pushing the two rotary molded parts 2 upwards, causing the tops of the two rotary molded parts 2 to open outwards in their natural state. Specifically, the first elastic element 6 includes a first spring 62 and a push head 61. The support base 1 has a push groove 1c that communicates with the opening groove 1a and extends longitudinally. The push head 61 is slidably connected in the push groove 1c. The first spring 62 is supported between the push head 61 and the lower mold base 8. The upper part of the push head 61 abuts against the bottom of the two rotationally formed parts 2.

[0044] The force transmission block 3 is longitudinally slidably mounted on the lower die base 8, and partially located within the drive groove 22. The top of the force transmission block 3 is used to place and support the metal blank, and the bottom is connected to the lower die base 8 via the second elastic element 9. Figure 5As shown, the second elastic element 9 includes a second spring 91, a first guide post 92 fixed on the lower mold base 8, and a first guide groove longitudinally formed on the force transmission block 3. The first guide post 92 is slidably connected to the first guide groove. Two first guide posts 92 and corresponding first guide grooves are provided to enhance the stability of the force transmission block 3 during movement. The second spring 91 is sleeved on the first guide post 92 located between the force transmission block 3 and the lower mold base 8, and provides an upward elastic restoring force for the force transmission block 3. Of course, the specific structural form of the second elastic element 9 is not limited to this. Those skilled in the art can use other elastic elements with similar guiding and restoring functions according to actual needs.

[0045] The upper die assembly includes an upper die base 11 connected to the output end of the stamping machine and a first downward pressure rod 4 disposed on the upper die base 11. In the closed state, the first downward pressure rod 4 moves downward, pressing against the metal blank and driving the force transmission block 3 to move downward. The bottom of the portion of the force transmission block 3 located within the drive groove 22 presses against the bottom of the drive groove 22, thereby driving the two rotary forming parts 2 to rotate and converge towards each other around their respective rotating parts 21 to form the sidewall of the metal blank. The portion of the force transmission block 3 located within the drive groove 22 is a force transmission arm 31 extending outward from the sidewall of the force transmission block 3. Further, as... Figure 6 As shown, to ensure that the first pressing rod 4 has a downward pre-pressing stroke relative to the upper mold base 11, the first pressing rod 4 is longitudinally slidably connected to the upper mold base 11, and a third elastic element 10 is provided between the first pressing rod 4 and the upper mold base 11. The third elastic element 10 includes a third spring 101, two second guide posts 102 fixed on the first pressing rod 4, and two corresponding second guide grooves opened on the upper mold base 11. The second guide posts 102 are slidably connected to the second guide grooves, and a limit block 103 is provided at the end of the second guide post 102 away from the first pressing rod 4 to prevent the second guide post 102 from dislodging from the upper mold base 11. The third spring 101 is sleeved on the second guide post 102 located between the upper mold base 11 and the first pressing rod 4. Of course, the specific structural form of the third elastic element 10 is not limited to this, and those skilled in the art can use other elastic components with similar guiding and resetting functions according to actual needs.

[0046] In the above method, by setting two rotary forming parts 2 with rotating parts 21 at the bottom and rotatable around them, and cooperating with the longitudinal movement of the force transmission block 3, the lateral friction force on the fixed point of the metal blank in the traditional process is transformed into a positive forming force applied by the rotary forming parts 2 to the side wall of the metal blank, with the contact point continuously changing. During the forming process, the inner side of the rotary forming part 2 and the side wall of the metal blank start from line contact and gradually become surface contact as they rotate and close. The direction of the force is always perpendicular to the tangent of the contact point, effectively avoiding the scraping of the metal surface by the traditional lateral sliding friction, thereby eliminating the generation of metal wires and effectively improving the forming quality, overall performance and production stability of the terminal.

[0047] In this embodiment, the elastic force of the third elastic element 10 is configured to be greater than that of the second elastic element 9. In this way, at the initial stage of mold closing, the first pressing rod 4 can overcome the supporting force of the second elastic element 9 first, firmly press the metal blank onto the force transmission block 3, and drive the force transmission block 3 and the metal blank to move downward together. This ensures that the metal blank is in a reliable pressing state before the rotational forming action is started, thereby avoiding forming defects caused by blank displacement or loosening.

[0048] In this embodiment, to further optimize the forming effect, the upper die assembly also includes a second pressing rod 5. The second pressing rod 5 is fixedly connected to the upper die base 11 and is located directly above the two rotary forming parts 2. Before the upper die assembly moves downward, the downward stroke of the first pressing rod 4 is greater than that of the second pressing rod 5. After the first pressing rod 4 drives the rotary forming part 2 to complete the sidewall forming of the metal blank, as the upper die assembly continues to move downward, the second pressing rod 5 presses against the top of the two rotary forming parts 2, ensuring that the two rotary forming parts 2 can completely and stably close after rotating into position, reducing dimensional fluctuations caused by elastic reset or gaps, and ensuring the dimensional consistency of the terminal products formed in each stroke. Furthermore, a shaping groove can be provided on the lower end face of the second pressing rod 5. The shaping groove includes a clearance groove for accommodating the remaining area of ​​the top of the metal blank, and a forming protrusion for final shaping of a specific top structure of the metal blank. The clearance groove can avoid interference with areas that do not require pressure, and the forming protrusion can apply shaping force to a specific structure on the top of the terminal during the final compaction stage, thereby simultaneously achieving sidewall forming and top shaping of the metal blank in one stroke, further improving the dimensional accuracy and shape consistency of the terminal product.

[0049] The present invention also discloses a precision stamping forming process, which uses the above-mentioned precision stamping forming die and includes the following steps:

[0050] S1. Place the pre-cut or pre-formed metal blank on top of the force transmission block 3.

[0051] S2. Drive the output end of the press downward to drive the upper die assembly downward, so that the first pressing rod 4 presses against the metal billet.

[0052] S3. The upper mold assembly continues to descend, and the force transmission block 3, driven by the first pressing rod 4, carries the metal billet down together.

[0053] S4. During the downward movement of the force transmission block 3, the bottom of the portion of the force transmission block 3 located in the drive groove 22 presses against the bottom of the drive groove 22, thereby driving the two rotary forming parts 2 to rotate and close together around their respective rotating parts 21.

[0054] S5. During the rotational closing process of the two rotary forming parts 2, the inner sides of the two rotary forming parts 2 begin to make line contact with the sidewall of the metal billet and gradually change to surface contact to perform positive forming of the sidewall of the metal billet. Subsequently, the second pressure bar completes the final compaction and shaping of the top of the metal billet.

[0055] In the above process, the sidewall of the metal blank is formed by rotating and closing the two rotary forming parts 2. While ensuring the high yield strength forming requirements, it avoids lateral friction at a single point, making it less likely for metal wires to be generated in the terminal products. The process is stable and controllable, effectively improving the dimensional accuracy, surface quality, production consistency and yield of the terminal products.

[0056] The present invention also discloses a metal component, which is manufactured by the above-mentioned precision stamping die or precision stamping process. The sidewall of the metal component bears the positive forming force during the forming process, and its sidewall is free of metal wires or micro burrs caused by lateral friction.

[0057] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A precision stamping die, characterized in that, include: Lower mold base; A support base is fixed on the lower mold base. The support base has an opening groove with a gradually expanding opening. Rotating grooves are provided on both sides of the bottom of the opening groove. Two rotary forming parts are symmetrically arranged in the opening slot. Each rotary forming part has a rotating part on the opposite side of its bottom. The rotating part is rotatably connected to the corresponding rotating slot. A driving slot is provided between the two rotary forming parts. The first elastic element is disposed in the support base and acts on the bottom of the two rotary forming parts to push the two rotary forming parts upward, so that the tops of the two rotary forming parts open outward in their natural state. The force transmission block is longitudinally slidably disposed on the lower mold base and partially located in the drive groove. The top of the force transmission block is used to place and support the metal billet, and the bottom is connected to the lower mold base through a second elastic element. The upper mold assembly includes a first pressing rod located above the two rotary forming parts. When the first pressing rod moves downward, it can press against the metal blank and drive the force transmission block to move downward. The bottom of the portion of the force transmission block located in the drive groove presses against the bottom of the drive groove, thereby driving the two rotary forming parts to rotate towards each other around their respective rotating parts and close together to form the sidewall of the metal blank.

2. The precision stamping die according to claim 1, characterized in that: The upper mold assembly further includes an upper mold base, the first pressing rod is longitudinally slidably connected to the upper mold base, and a third elastic element is provided between the first pressing rod and the upper mold base so that the first pressing rod has a downward pre-pressing stroke relative to the upper mold base.

3. The precision stamping die according to claim 2, characterized in that: The elastic force of the third elastic element is greater than that of the second elastic element.

4. The precision stamping die according to claim 2, characterized in that: The upper mold assembly also includes a second lower pressure rod, which is fixedly connected to the upper mold base and located directly above the two rotary forming parts; Before the upper mold assembly moves downward, the downward stroke of the first pressing rod is greater than that of the second pressing rod. After the first pressing rod drives the rotary forming component to complete the sidewall forming of the metal blank, as the upper mold assembly continues to descend, the second pressing rod presses against the top of the two rotary forming components.

5. The precision stamping die according to claim 4, characterized in that: A shaping groove is provided on the lower end face of the second pressing rod to accommodate and shape the top of the metal billet.

6. The precision stamping die according to claim 1, characterized in that: The rotating part is a cylindrical rotating shaft, and the rotating groove is an arc-shaped groove that matches the rotating shaft.

7. The precision stamping die according to claim 1, characterized in that: The first elastic element includes a first spring and a push head. The support base has a push groove that communicates with the opening slot. The push head is slidably connected in the push groove. The first spring is supported between the push head and the lower mold base, and the top of the push head abuts against the bottom of the two rotationally formed parts.

8. The precision stamping die according to claim 1, characterized in that: The portion of the force transmission block located within the drive groove is a force transmission arm extending outward from the side wall of the force transmission block.

9. A precision stamping forming process, employing the precision stamping forming die as described in any one of claims 1 to 8, characterized in that: The precision stamping process includes the following steps: S1. Place the metal billet on top of the force transmission block; S2. Drive the upper mold assembly downward so that the first pressing rod presses against the metal billet; S3. The upper mold assembly continues to descend, and the force transmission block carries the metal billet down together under the drive of the first pressing rod; S4. During the downward movement of the force transmission block, the bottom of the portion of the force transmission block located in the driving groove presses against the bottom of the driving groove, thereby driving the two rotary forming parts to rotate and close towards each other around their respective rotating parts. S5. During the rotational closing process of the two rotary forming parts, the inner sides of the two rotary forming parts start from line contact with the sidewall of the metal blank and gradually change to surface contact, so as to perform positive forming on the sidewall of the metal blank.

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