FPC die capable of dispersing punching stress

Abstract

The utility model discloses a dispersed FPC blanking die of stress of punching, including by top to bottom setting's top plate, pressing plate, needle plate, panel, female die and bottom plate, and the lower surface of pressing plate is installed with guide pillar and the guide pillar passes needle plate and panel in proper order, and female die is provided with the guide groove of corresponding guide pillar, the lower surface of needle plate is installed with a plurality of punch pins in parallel, and female die is provided with the female die of corresponding punch pin one by one up and down, and the blade edge end face of a plurality of punch pins forms height step in the stamping direction.

Description

Technical Field

[0001] This utility model relates to the field of circuit board technology, and in particular to an FPC punching die for dispersing punching stress. Background Technology

[0002] When FPC products are long and densely packed, there are too many openings to punch, so a large number of punches are required. However, in traditional mold design, all punches have the same cutting edge height, which causes all punches to contact at the same time and reach the maximum punching force at the same time during the stamping stroke. The peak value of the combined force is too high. Therefore, conventional tonnage punch presses (25t-35t) cannot provide the peak pressure to punch through all holes at the same time, which leads to stress concentration defects. That is, the die is prone to elastic deformation under instantaneous concentrated load, resulting in burrs and flanging at the punching edge. This leads to the product not being punched continuously and the poor punching appearance caused by die deformation.

[0003] To avoid the above problems, the current industry practice is to use multiple sets of molds for multiple punching operations, or to use large-tonnage punch presses to reduce defects, but this is costly and inefficient. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides an FPC punching die for dispersing punching stress, comprising a top plate, a pressure plate, a pin plate, a face plate, a female mold, and a bottom plate arranged sequentially from top to bottom. The lower surface of the pressure plate is equipped with guide posts that pass through the pin plate and the face plate in sequence. The female mold has guide grooves corresponding to the guide posts. The lower surface of the pin plate is equipped with a plurality of punches arranged in parallel, and the female mold has cavities that correspond one-to-one with the punches. The cutting edge faces of the multiple punches form a height difference in the stamping direction to reduce the instantaneous peak resultant force during punching.

[0005] The punch has a toothed groove on its cutting edge end face, thereby reducing the effective cutting area of ​​the cutting edge end face to further reduce the instantaneous peak resultant force.

[0006] The base plate has waste discharge ports that correspond one-to-one with the concave mold.

[0007] Through the above technical solution, this utility model designs the effective cutting edge end faces of multiple punches arranged in parallel into a stepped structure with different heights. By changing the physical structure of the punches, it actively disperses and reduces the instantaneous peak punching force and the instantaneous load on the die. Thus, without increasing the number of mold sets or using high-tonnage punch presses, it effectively solves the problems of incomplete punching and appearance defects such as burrs and flanging caused by the elastic deformation of the die, while ensuring production efficiency. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0009] Figure 1 This is a schematic diagram of the mold structure disclosed in the embodiment of this utility model; Figure 2 This is a schematic diagram of the punch structure disclosed in the embodiment of this utility model.

[0010] In the diagram: 11. Top plate; 12. Pressure plate; 13. Needle plate; 14. Front plate; 15. Female mold; 16. Bottom plate; 17. Guide pillar; 18. Guide groove; 19. Punch; 191. Tooth groove; 192. Cutting edge end face; 20. Die cavity; 21. Waste outlet. Detailed Implementation

[0011] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0012] refer to Figure 1 and 2 The present invention provides an FPC punching die for dispersing punching stress, comprising a top plate 11, a pressure plate 12, a needle plate 13, a panel 14, a female mold 15, and a bottom plate 16 arranged sequentially from top to bottom. A guide post 17 is installed on the lower surface of the pressure plate 12 and passes through the needle plate 13 and the panel 14 in sequence. The female mold 15 has a guide groove 18 corresponding to the guide post 17. A plurality of punches 19 are installed side by side on the lower surface of the needle plate 13, and a cavity 20 corresponding to the punches 19 is opened on the female mold 15. A waste discharge port 21 corresponding to the cavity 20 is opened on the bottom plate 16.

[0013] Among them, the cutting edge end faces 192 of multiple punches 19 form a height difference in the stamping direction, and the cutting edge end faces 192 of the punches 19 are provided with tooth grooves 191 to reduce the effective cutting area of ​​the cutting edge end faces 192.

[0014] Specifically, through precision grinding (such as grinding with a 618 grinder), the height of the cutting edge face of each punch relative to the mounting reference surface is precisely controlled, so that it forms a specific step difference (height difference) in the stamping direction.

[0015] Specifically, the design basis for the step difference is as follows: The size of the step difference is a key design parameter and needs to be optimized according to the thickness (t) of the FPC material to be punched. The typical step difference range is 0.3mm~1.0mm (for example, for common FPC materials, 0.5mm is an effective starting design value, which can be adjusted according to the specific product). The step difference should ensure that the punches of different levels can effectively complete their respective punching stages.

[0016] The working principle of this utility model: 1. Staged contact and punching: When the mold descends, the group of punches with the most prominent (highest) cutting edge face (first stage) is the first to contact the FPC material and begin punching; 2. Staggered force application to reduce instantaneous peak combined force: When the first-stage punch cuts into the material to a certain depth (approaching or reaching 50%-80% of the material thickness, depending on the step design), the second-stage punch group begins to contact the material and apply punching force. This design disperses the total peak punching force that originally needed to be reached instantaneously to different time points in the stamping stroke. 3. Distribute load and reduce instantaneous deformation of the die: Since the blanking force is applied to the die in stages and gradually, the peak value of the instantaneous load on the cutting edge area of ​​the die is also greatly reduced, which effectively suppresses the instantaneous elastic deformation of the die. 4. Maintain ideal clearance and improve punching quality: The reduction of die deformation ensures that the fitting clearance between the punch and the die edge can be maintained more uniformly and closer to the design value throughout the punching process. The shearing action on the material during separation is more uniform and sufficient, thereby significantly reducing or even eliminating defects such as burrs and flanging caused by uneven clearance or instantaneous deformation. 5. Meets the capabilities of conventional equipment: The reduced instantaneous peak resultant force after the stepped design allows work that originally required a high-tonnage punch press to be successfully completed in one pass on a punch press with a conventional nominal pressure (such as 25t-35t).

[0017] Therefore, this utility model has the following advantages: 1. Significantly reduced costs and space requirements: Only one mold is needed to complete the work, avoiding the design, manufacturing costs and management expenses of multiple molds; there is no need to purchase expensive and large-scale high-tonnage stamping equipment, greatly reducing equipment investment and factory requirements; 2. Improve production efficiency and precision: One-time stamping eliminates the need for multiple positioning and operation time in multiple stamping operations, significantly improving efficiency; one-time stamping also eliminates the cumulative error caused by multiple positioning, improving hole position accuracy; 3. Effectively improves punching quality: By dispersing instantaneous load through a stepped design, the elastic deformation of the die is suppressed, and a stable punching clearance is maintained, which fundamentally reduces the generation of appearance defects such as burrs and flanging, and improves product yield and reliability. 4. Breaking through equipment tonnage limitations: It innovatively solves the pressure bottleneck problem of punching high-density, large-size FPC products on conventional tonnage punch presses, expanding the processing capacity of existing equipment; 5. Simple structure and easy to implement: The core innovation lies in the differentiated design of the cutting edge height of the punch, which can be achieved through mature precision grinding. There is no need to make complex modifications to the main structure of the mold, making it easy to implement and promote in the existing mold design and manufacturing process.

[0018] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to the above 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 present invention. Therefore, the present 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. An FPC punching die for dispersing punching stress, comprising a top plate (11), a pressure plate (12), a pin plate (13), a panel (14), a female mold (15), and a bottom plate (16) arranged sequentially from top to bottom. A guide post (17) is installed on the lower surface of the pressure plate (12), and the guide post (17) passes through the pin plate (13) and the panel (14) in sequence. The female mold (15) has a guide groove (18) corresponding to the guide post (17). A plurality of punches (19) are installed side by side on the lower surface of the pin plate (13), and a cavity (20) is opened on the female mold (15) corresponding to the punches (19) one by one. Its features are, The cutting edge faces (192) of the plurality of said punches (19) form a height difference in the punching direction to reduce the instantaneous peak resultant force during punching.

2. The FPC punching die for dispersing punching stress according to claim 1, characterized in that, The cutting edge end face (192) of the punch (19) is provided with a tooth groove (191), thereby reducing the effective cutting area of ​​the cutting edge end face (192) to further reduce the instantaneous peak resultant force.

3. The FPC punching die for dispersing punching stress according to claim 1, characterized in that, The base plate (16) has a waste discharge port (21) that corresponds one-to-one with the concave mold (20).

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