Integrated precise blanking die with burr removing function and blanking method

Abstract

The invention discloses an integrated precise blanking die with a burr removing function and a blanking method, and belongs to the field of metal plate stamping machining. An upper die assembly of the die is provided with a finishing female die and an ejection device, and a lower die assembly is provided with a main male die. A first cutting edge, a conical transition face, a second cutting edge and a step structure are integrated in a cavity of the finishing female die. During blanking, the finishing female die moves downwards to finish blanking through the first cutting edge and the main male die, and burrs are preformed synchronously through the conical transition face; and when the finishing female die returns, the material ejecting device pushes the blanking piece to move downwards, burrs are cut and removed through the second cutting edge, and chippings are collected by the step structure. Blanking and deburring are integrally completed in one punching stroke, the efficiency and the product quality are remarkably improved, and the cost is reduced.

Description

An integrated precision blanking die with burr removal function and a blanking method Technical Field

[0001] This invention belongs to the field of metal sheet stamping technology, specifically relating to an integrated precision blanking die with burr removal function and a blanking method. Background Technology

[0002] In sheet metal stamping, blanking is a fundamental process for obtaining parts with the desired shape and contour. Traditional blanking dies consist of an upper die (punch) and a lower die (die). By setting a reasonable punch-die clearance, the material is separated under shearing action. However, even when the die clearance is adjusted to its theoretical optimal value, due to factors such as material plastic deformation, die wear, and equipment precision, burrs of varying degrees are still unavoidable at the edges of the blanked section (especially the section near the die). These burrs not only affect the appearance and quality of the product but also pose potential risks such as scratches and poor fit during subsequent assembly and use.

[0003] Currently, the common method for removing burrs from blanked parts is to add a separate process step, such as filing, grinding, mechanical polishing, vibratory finishing, or secondary trimming dies. These methods have significant drawbacks: they require additional equipment and operators, leading to production interruptions, reduced production efficiency, and increased production costs; at the same time, secondary handling and clamping may also cause scratches or deformation on the product surface, affecting the final quality.

[0004] Therefore, there is an urgent need for a technical solution that can be efficiently integrated with the blanking process and remove burrs directly at the blanking station to achieve "burr-free blanking" and improve production efficiency and product quality. Summary of the Invention

[0005] This invention aims to overcome the shortcomings of existing technologies and provide an integrated precision blanking die and blanking method with burr removal function. Through its unique structural design, the die not only completes blanking in a single stamping stroke, but also uses an ejector device integrated into the die and a special cavity structure to remove burrs from the edges of the blanked part in situ during the return stroke, thereby directly obtaining a burr-free product and eliminating the need for a separate subsequent burr treatment process.

[0006] To achieve the above technical objectives, the following technical solution is adopted: On the one hand, the present invention provides an integrated precision blanking die with burr removal function, including an upper die assembly and a lower die assembly. The upper die assembly is installed on the press slide, and the lower die assembly is installed on the press worktable. The upper die assembly includes a finishing die and an ejector device located above the finishing die. The lower die assembly includes a main punch. The finishing die is provided with a continuous cavity that cooperates with the main punch. The continuous cavity includes a first cutting edge located at the lower entrance for cooperating with the main punch to complete the initial separation of the sheet metal, a tapered transition surface extending upward from the first cutting edge and gradually decreasing in cross-sectional size, a second cutting edge located at the end of the tapered transition surface, a stepped structure located above the second cutting edge, and a product cavity located above the stepped structure for accommodating the blanked part.

[0007] Preferably, the profile dimension of the first cutting edge is larger than the working cross-sectional dimension of the main punch to form a punching gap; the profile dimension of the second cutting edge is equal to the nominal dimension of the blanked product to perform final dimensional calibration of the product and remove burrs.

[0008] Preferably, the cone angle of the tapered transition surface is 0.1° to 0.5°.

[0009] Preferably, the top material device is a highly elastic rubber.

[0010] Preferably, the mold is an inverted structure, with the finishing die fixed to the upper mold base of the upper mold assembly and the main punch fixed to the lower mold base of the lower mold assembly.

[0011] On the other hand, the present invention provides a blanking method using the above-mentioned mold, comprising the following steps: S1. Blanking step: driving the upper mold assembly downward, and punching out a blanking part with burrs by cooperating with the main punch through the first cutting edge of the finishing die; S2. Deburring step: when the upper mold assembly begins to return upward, the ejector device pushes the blanking part downward relative to the finishing die, so that the burrs on the edge of the blanking part are sheared and removed when passing the second cutting edge; S3. Demolding step: the upper mold assembly continues to return, and the product separates from the mold.

[0012] Preferably, in the S1 blanking step, the blanking part enters the continuous cavity of the finishing die and is located above the stepped structure.

[0013] Preferably, in the S2 deburring step, the blanking part moves downward under the push of the top material device, passes through the area where the stepped structure is located, and reaches the second cutting edge.

[0014] Preferably, the blanking step, deburring step, and demolding step are completed continuously within one complete working cycle of the press slide.

[0015] Compared with the prior art, the present invention has the following significant advantages: 1. High efficiency and saving process: The blanking and deburring processes are perfectly integrated into one stamping stroke, realizing "one mold for two purposes", completely eliminating the need for subsequent separate deburring processes and the required equipment, manpower and space, and greatly improving production efficiency and process continuity.

[0016] 2. Stable quality and thorough deburring: Deburring is performed through precision shearing using a rigid mold structure, which is far superior to manual grinding or vibratory polishing. The deburring is thorough and uniform, resulting in high-quality product cross-sections and good dimensional stability.

[0017] 3. Reduce overall costs: Although the mold manufacturing cost increases slightly, the overall production cost of the product is significantly reduced due to the reduction of processes, the decrease in scrap rate, and the saving of energy and manpower for secondary processing.

[0018] 4. Compact and reliable structure: The deburring function is achieved through the structure of the mold itself (conical transition surface, second cutting edge, ejector device) and the natural stroke of the press. It does not require a complex additional drive or control system, but only utilizes the stroke and power of the press itself, which is highly reliable and easy to maintain. Attached Figure Description

[0019] The present invention will now be described with reference to the accompanying drawings.

[0020] Figure 1 is a cross-sectional schematic diagram of the mold of the present invention in its initial state before the stamping begins.

[0021] Figure 2 is a cross-sectional view of the mold of the present invention when the initial blanking (the blanking step is completed) is completed.

[0022] Figure 3 is a cross-sectional view of the mold of the present invention during the secondary finishing and deburring process (during the deburring step).

[0023] Figure 4 is a cross-sectional view of the mold of the present invention at the end of the demolding step. Figure 5 is a partially enlarged structural diagram of the continuous cavity of the finishing die in the mold of the present invention.

[0024] In the figure: 1-Main punch; 2-Sheet metal; 3-Finishing die; 31-First cutting edge; 32-Conical transition surface; 33-Second cutting edge; 34-Step structure; 35-Product cavity; 4-Ejector device; 5-Unloading part. Detailed Implementation

[0025] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] As shown in Figures 1 to 4, the present invention provides an integrated precision blanking die with burr removal function, employing an inverted structure. The lower die assembly is fixed to the press worktable via a lower die base, on which the main punch 1 is mounted. The upper die assembly is connected to the press slide via an upper die base, on which a finishing die 3 is mounted. Above the finishing die 3, a highly elastic rubber element serving as an ejector device 4 is mounted.

[0027] The finishing die 3 has a continuous cavity. As shown in the enlarged view of Figure 5, the continuous cavity consists of, from top to bottom: a product cavity 35, a stepped structure 34, a second cutting edge 33, a tapered transition surface 32, and a first cutting edge 31. The first cutting edge 31 is located at the lowermost entrance of the continuous cavity, and its size is slightly larger than that of the main punch 1, forming a reasonable clearance for blanking. The size of the second cutting edge 33 is equal to the nominal size of the blanking part 5. The tapered transition surface 32 connecting the first cutting edge 31 and the second cutting edge 33 preferably has a taper angle of 0.1° to 0.5°, forming a smooth, narrowing guide surface. The stepped structure 34 above the second cutting edge 33 is an annular groove with a cross-sectional size slightly larger than that of the second cutting edge 33. The ends of the stepped structure 34 and the tapered transition surface 32 together define the second cutting edge 33. The product cavity 35 is located in the cavity section above the stepped structure 34. This cavity is mainly used to accommodate the blanked part 5 after punching and to provide installation and operating space for the ejector device 4 (high-elasticity rubber). Its top is usually fixedly connected to the upper die base.

[0028] The working process and method of the mold of the present invention are as follows, and the entire process is completed continuously within one stamping cycle: 1. Loading and initial positioning (corresponding to the state in Figure 1): The metal sheet 2 to be processed is sent to the upper surface of the main punch 1 of the lower die assembly and positioned accurately. The press slide is at the top dead center, and the upper die assembly is lifted.

[0029] 2. Blanking Step (corresponding to the state in Figure 2): The press slide drives the upper die assembly downwards. The first cutting edge 31 of the finishing die 3 works together with the main punch 1 to shear the sheet metal 2, completing the blanking. At this time, a blank part 5 with the basic shape of the product but with burrs on the edges is punched away from the sheet metal and enters the continuous cavity of the finishing die 3. At the moment of blanking separation, burrs are generated on the edge of the blank part 5. As the upper die assembly continues to descend, the newly generated burrs on the edge of the blank part 5, which are still in a plastic state, come into contact with the tapered transition surface 32. Since the tapered transition surface 32 gradually narrows upwards (in the opposite direction of stamping), it exerts a continuous and uniform radial inward squeezing force on the burrs, guiding the irregular, curled burrs to a slightly outward-facing state, creating favorable morphological conditions for subsequent thorough shearing. At the end of the blanking, the blank part 5 is usually located in the product cavity 35, that is, the area above the stepped structure 34. The ejector device 4 is compressed during this downward movement, storing elastic potential energy.

[0030] 3. Deburring step (corresponding to the state in Figure 3): After the upper die assembly reaches the bottom dead center, it begins its return upward movement. At this time, the main punch 1 remains stationary. The compressed ejector device 4 releases its elasticity, pushing the blanking part 5, which is stationary in the product cavity 35, downward relative to the upward-moving finishing die 3.

[0031] The blanking part 5 first passes downward through the area where the product cavity 35 and the stepped structure 34 are located.

[0032] Subsequently, the outer edge of the blanking part 5 (which consists of relatively regular burrs pre-treated by the tapered transition surface 32) reaches the second cutting edge 33. The outline dimensions of the second cutting edge 33 are consistent with the nominal dimensions of the blanking product 5. When the blanking part 5 is forced through this precision cutting edge by the ejector device 4, all burrs protruding beyond the final outline of the product are cleanly and neatly sheared off from the root by the sharp edge of the second cutting edge 33, thereby directly obtaining a burr-free precision part with accurate dimensions and smooth edges.

[0033] At the moment the burr is sheared, the resulting metal fragments, under the shearing impact force, can be contained within the annular groove space formed by the stepped structure 34. This design helps prevent fragments from falling onto the finished product surface and causing scratches, and also prevents fragments from entering the precision mating surfaces of the mold, thereby protecting product quality and extending mold life.

[0034] 4. Demolding Step (corresponding to state in Figure 4): The upper mold assembly continues its return stroke. After passing the second cutting edge 33, the deburred blank part 5 smoothly separates from the main punch 1 under the continuous action of the ejector device 4 and is completely ejected from the finishing die 3. The blank part 5 falls into the collection device under the action of gravity. The debris contained in the stepped structure 34 can be collected and cleaned during regular maintenance.

[0035] 5. Cycle: The system is reset, a new sheet material 2 is fed in, and steps 1 to 4 above are repeated to achieve continuous and efficient automated production.

[0036] In summary, this invention cleverly divides a stamping cycle into two functional stages through a special cavity structure integrated on the finishing die 3: in the downward blanking stage, the conical transition surface 32 completes the "pre-forming" of newly formed burrs; in the upward return stage, the second cutting edge 33 completes the "final shearing" of the burrs, while the stepped structure 34 provides a space to accommodate the generated debris. This "step-by-step processing, one-time completion" design allows the blanking and deburring processes to be seamlessly integrated in a single stroke at the same station, achieving a simultaneous leap in production efficiency and product quality.

[0037] Other aspects of this invention that are not detailed herein are all conventional techniques known to those skilled in the art.

[0038] It should be noted that the terms “comprising,” “including,” or any other variations are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0039] The scope of protection of this invention is not limited to the technical solutions disclosed in the specific embodiments. Any modifications, equivalent substitutions, improvements, etc., made to the above embodiments based on the technical essence of this invention shall fall within the scope of protection of this invention.

Claims

1. An integrated precision blanking die with burr removal function, comprising an upper die assembly and a lower die assembly, wherein the upper die assembly is mounted on a press slide, and the lower die assembly is mounted on a press worktable; characterized in that: The upper mold assembly includes a finishing die (3) and an ejector device (4) located above the finishing die (3). The lower mold assembly includes a main punch (1). The finishing die (3) is provided with a continuous cavity that cooperates with the main punch (1). The continuous cavity includes a first cutting edge (31) located at the lower entrance for cooperating with the main punch (1) to complete the initial separation of the sheet metal (2), a tapered transition surface (32) extending upward from the first cutting edge (31) and with a gradually decreasing cross-sectional size, a second cutting edge (33) located at the end of the tapered transition surface (32), a stepped structure (34) located above the second cutting edge (33), and a product cavity (35) located above the stepped structure (34) for accommodating the blanking part (5).

2. The integrated precision blanking die with burr removal function according to claim 1, characterized in that: The first cutting edge (31) has a larger profile dimension than the working section dimension of the main punch (1) to form a punching gap; the second cutting edge (33) has a profile dimension equal to the nominal dimension of the blanking product to perform final dimension calibration of the product and cut off burrs.

3. The integrated precision blanking die with burr removal function according to claim 1, characterized in that: The cone angle of the conical transition surface (32) is 0.1° to 0.5°.

4. The integrated precision blanking die with burr removal function according to claim 1, characterized in that: The top material device (4) is made of high-elasticity rubber.

5. The integrated precision blanking die with burr removal function according to claim 1, characterized in that: The mold is an inverted structure, the finishing die (3) is fixed to the upper mold base of the upper mold assembly, and the main punch (1) is fixed to the lower mold base of the lower mold assembly.

6. A punching method using a die as described in any one of claims 1 to 5, characterized in that: Includes the following steps: S1. Blanking step: Drive the upper die assembly downward, and through the first cutting edge (31) of the finishing die (3) and the main punch (1), blanking out the blank part (5) with burrs; S2. Deburring step: When the upper die assembly starts to return upward, the ejector device (4) pushes the blank part (5) downward relative to the finishing die (3), so that the burrs on the edge of the blank part (5) are sheared and removed when passing the second cutting edge (33); S3. Demolding step: The upper die assembly continues to return, and the product is separated from the mold.

7. The punching method according to claim 6, characterized in that: In the S1 blanking step, the blanking part (5) enters the continuous cavity of the finishing die (3) and is located above the stepped structure (34).

8. The punching method according to claim 6, characterized in that: In the S2 deburring step, the blanking part (5) moves downward under the push of the top material device (4), passes through the area where the stepped structure (34) is located, and reaches the second cutting edge (33).

9. The punching method according to claim 6, characterized in that: The blanking step, deburring step, and demolding step are completed continuously within one complete working cycle of the press slide.

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