Technical field

The invention relates to a punching die, in particular to a punching die for punching paper-plastic products.

Background

The use of, for example, paper and plastic products to package products is becoming more and more common in modern society. For example, a common example is a paper tray used to carry products in the packaging boxes of electronic products such as mobile phones and personal tablets. Taking such a tray as an example, the open edges of which are generally flat and are obtained by using a mold to separate a blank comprising a plurality of trays, the blank being formed by pressing.

In the prior art, steel wire dies are generally used to process blanks. On the one hand, the screw plate is usually used to fasten the template and the machine, which is easy to loosen under pressure, resulting in frequent displacement of the mold, and thus that the product gets a large deviation from the expected quality.

A typical situation is poor edge deviation. In addition, this results in time-consuming retooling and calibration operations that might require hours to perform, resulting in low throughput, labor, and wasted production materials.

Moreover, the base of the lower die of the steel wire die and the blade of the upper die are generally made of wood or bakelite, which have low density, low strength, and are easily deformed by force, so the machining accuracy and positioning accuracy are poor. Moreover, the die blade is formed by manual bending, and the cutting edge of the knife can only form a flat punching surface, but cannot be processed into an arc surface or an inclined surface to punch products of corresponding shapes. For special-shaped surface products, the solution in the prior art is to open the mold separately for each product, which is expensive.

Summary of the invention

The purpose of the present invention is to provide a punching die that overcomes the above-mentioned problems. The punching die according to the present invention is characterized in that the punching die comprises: an upper die assembly comprising an upper die plate, a cutting plate fixed to the upper die plate and comprising a blade formed thereon; and a lower die assembly comprising: a lower die plate, a cutting seat fixed to the lower die plate and adapted to support a piece to be punched, and a support located between the lower die plate and the cutting seat and adapted to support the cutting seat, the support comprising at least one supporting member which is selected from a modular supporting member set.

In the punching die of the present invention, due to the use of a modularly designed bracket, only the blade and the blade holder can be designed for the part to be punched, and such blade and blade holder can be very light and easy to replace. The lower die plate can be fixed on the machine table as a common part suitable for various parts to be punched, and no need to replace the lower die plate no matter what kind of parts to be punched. In addition, due to the use of this modular design of the bracket, for different tool holders, one or several geometric brackets can be selected from the ready-made support group. That is to say, in the punching die according to the present invention, the upper and lower die plates and the set of support members can be used as common components, and only the die (the die plate and the die seat) needs to be designed, so that the overall cost of the die is reduced to only the original fraction of the mold.

Preferably, the modular support set includes at least a support having a first geometry and a support having a second geometry different from the first geometry.

Preferably, the bracket includes a plurality of supports that are spliced together to form the bracket.

Preferably, the support member is at least one of a rectangular block, a square block, a triangular block, and an L-shaped block. Thereby, the desired stent can be quickly composed by selecting the supports from the set of supports. In addition, various geometric shapes and a limited number of support members provide very diverse and flexible options for the shape of the stent, that is, it is not necessary to manufacture an excessive number of support members to meet the needs of stents of various shapes. Preferably, the support is of aluminium alloy. Such supports have the advantages of low cost, high compression capacity, and long service life.

Preferably, the blade holder is stainless steel. Such a holder has the advantages of a smooth surface, good mechanical strength, and corrosion resistance. This avoids the increase of errors due to deformation during compression, and prolongs the service life. Preferably, the blade is formed integrally with the cutting plate. Preferably, the blade is a special-shaped blade formed by CNC machining. Preferably, the blade and the cutting plate are integrally formed by SKD11.

The cutting edge according to the present invention has high precision, and along the direction of the axis Z, the cutting board and the cutting edge can be designed into any desired shape for special-shaped parts, such as arc surface, inclined surface, etc. Die- cut pieces offer a comprehensive selection.

Preferably, the lower template includes a plurality of lower template positioning holes, each of the lower template positioning holes includes a threaded section and a positioning section, the tool seat includes a tool seat positioning hole, and the support member includes a support member positioning hole.

Preferably, the lower die assembly further comprises a hexagonal socket head shoulder screw, which passes through the tool seat positioning hole, the support member positioning hole and the lower template positioning hole, and is threadedly coupled to the threaded segment.

The lower die assembly is realized through the simple operation of positioning with one pin, which not only is easy to operate, fast to install, saves manpower, but also does not easily produce relative displacement between multiple parts, to ensure the punching accuracy.

Preferably, the plurality of lower template positioning holes form a lower template positioning hole array. Preferably, the upper template includes a plurality of upper template positioning holes, and the plurality of upper template positioning holes form an upper mold positioning hole array.

The positioning hole arrays of the upper template and the lower template according to the present invention can be adapted to mount thereon blade plates and brackets with different shapes.

The die-cutting die according to the present invention can be used in particular for the die-cut fiber-based product, such as paper- based products or molded fiber products.

Brief description of the figures

Figure 1 is a schematic exploded perspective view of a punching die according to an embodiment of the present invention;

Figures 2A - 2C are schematic perspective views of the lower die assembly of the punching die shown in FIG. 1, showing how the lower die assembly is assembled;

Figure 3 is a partial perspective cross-sectional view of the assembled lower die assembly along a cross- section through the aligned positioning holes of the lower die plate, support and tool holder;

Figure 4A is a schematic perspective view of an upper die assembly of a punching die according to the present invention;

- sectional view of the blade of the upper die assembly according to the present invention;

Figure 5A is a cross-sectional side view of the upper die assembly and the lower die assembly of the punching die according to the present invention after closing;

Figure Figure 5B is an enlarged view of the portion circled by box A in Figure 5A; Figure 6 is an example of a special-shaped part obtained by punching using the punching die according to the present invention; Figure 7A is a schematic perspective view of an upper die assembly used for punching out the special-shaped piece shown in FIG. 6; and

Figure 7B is an enlarged view of one of the elements of the blade shown in Figure 7A, in order to show its shape more clearly.

Detailed description

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings of the embodiments of the present invention.

Unless otherwise defined, technical or scientific terms used herein should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. "Comprising" or "including" and similar words mean that the elements or things appearing before the word encompass the elements or things recited after the word and their equivalents, but do not exclude other elements or things.

In order to better describe the technical solution according to the present invention, an orthogonal coordinate system XYZ is established, wherein the XY plane formed by the axes X and Y is the plane on which the punching die 1 is placed in the normal working state, and the axis Z is vertical On the X Y plane and its positive direction points to the upper die assembly. The terms "upper" and "lower" directions are defined with respect to axis Z.

FIG. 1 shows a schematic perspective view of a punching die 1 according to an embodiment of the present invention.

As shown in FIG. 1, the punching die 1 includes an upper die assembly 10 and a lower die assembly 20. In particular, the die cutting die is used for die-cutting fiber-based products. In normal operating conditions, the lower die assembly 20 is arranged in a plane defined by the axes X and Y, such as the machine plane.

The lower die assembly 20 includes a lower die plate 210, and the lower die plate 210 may be a rectangular plate with a certain thickness. In a normal working state, the lower die plate 210 is fixed on a workbench.

The lower die assembly 20 also includes a cutting seat 220, which is fixed to the lower die plate 210 and is adapted to support the part to be punched 90. The part 90 to be punched may be a fiber-based product that has not been cut, such as a molded fiber tray after being pressed. In the stamping die, these molded fiber products are cut into the desired finished products. In the example shown in FIG. 1, the piece 90 to be die-cut will be die-cut into four generally rectangular finished products as desired.

The lower die assembly 20 also includes a support 230. The support 230 is located between the lower template 210 and the cutting seat 220 and is adapted to support the cutting seat 220. The cutting seat 220 is fixed to the lower die plate 210 via the support 230, that is, the cutting seat 220 is indirectly fixed to the lower die plate 210. One example of the punching die 1 according to the present invention will be described in detail below with reference to the examples of Figs. 2A to 2C.

FIG. 2A is a schematic perspective view of the lower die plate 210 of the lower die assembly 20, showing the side of the lower die plate 210 facing the upper die plate 110. The lower die plate 210 is, for example, a generally rectangular-shaped plate. Four corners of the lower die plate 210 are respectively provided with guide posts 218 extending in the axial direction Z for guiding and positioning the upper die plate 110 during the punching process, which will be described in detail below.

The lower template 210 may include a plurality of lower template positioning holes 211. In the preferred embodiment shown in FIGS. 2A to 2C, these lower template positioning holes 211 form an array of lower template positioning holes. The support 230 may include at least one supporting member 231, as shown in FIG. 2B , the supporting member 231 is fixed on the lower die plate 210 , and the cutting seat 220 is fixed on the support 230 formed by the supporting member 231 (Figure 2C ). In the technical solution according to the present invention, the supporting members 231 constituting the support 230 may be selected from a modular support group. Flerein, a modular support member group refers to a group composed of a plurality of support members, in which the support members are independent from each other to form an individual module, and each support member is formed in a predetermined shape. In use, one or more supports can be selected from the modular support group according to the shape of the tool holder to form a bracket. In the punching die of the present invention, due to the use of a modularly designed bracket, only the blade and the blade holder can be designed for the part to be punched, and such blade and blade holder can be very light and easy to replace. The lower template can be fixed on the machine table as a common part suitable for various tool holders, and no need to replace the lower template no matter what kind of parts to be punched.

The modular support set includes at least a support having a first geometry and a support having a second geometry, the second geometry being different from the first geometry. Further, in order to support the tool holder, the support 230 may include a plurality of supporting pieces 231, and the plurality of supporting members 231 are spliced together to form the support 230. For example, in the example shown in FIG. 2C, the cutting seat 220 has a rectangular outer frame with a cross frame in the middle, so as to divide the entire tool holder 220 into 4 identical areas. At this time, as shown in FIG. 2B, a plurality of rectangular elongated supporting members 231 may be selected, and these members 231 may have approximately the same height (in the direction of the axis Z), but may have different lengths (extends in the X Y plane). The support 230 formed by splicing these selected support members 231 together includes an area suitable for supporting the cutting seat 220.

It will be appreciated that the support member 231 may have a shape other than that shown in the figures. For example, the support member 231 can be at least one of a rectangular block, a square block, a triangular block, and an L-shaped block, which can be combined as required to quickly form a tool seat suitable for different shapes. Due to the use of this modularly designed bracket, for different tool holders, brackets with different geometric shapes at the splices of the support parts can be selected from the ready made support parts without the need to re-open the mold. That is to say, in the punching die according to the present invention, the upper and lower die plates and the set of support members can be used as general parts, and only the die (the die plate and the die seat) needs to be designed, so that the overall cost of the die is reduced to only a fraction of the original.

Positioning and fixing methods of the lower template 210, the support member 231 and the tool seat 220 will be described below with reference to FIG. 3. Due to the fact that under pressure, multiple components stacked along the pressure direction are prone to relative dislocation, resulting in poor product accuracy and high defect rate. Therefore, solving this technical problem is also a key. FIG. 3 is a partial perspective sectional view of the lower die plate 210, the support 230 and the cutting seat 220 of the lower die assembly 20 shown in FIG . 2C after being assembled and fixed, along a section through the lower mold plate 210. The aligned positioning holes of the support 231 and the tool seat 220.

Specifically, as shown in FIG. 3, the lower template positioning hole 211 includes a threaded section 211A and a positioning section 211B, and the threaded section 211A is located below and adjacent to the positioning section 211B. Correspondingly, the tool seat 220 includes a tool seat positioning hole 221, and the support member 231 includes a support member positioning hole 2311. The positioning hole of the lower template, the positioning hole of the support and the positioning hole of the tool seat extend along the direction of the axis Z. The cutting seat 220, the respective supports of the bracket 230, and the lower template 210 can be positioned and fixed to each other by the socket head cap screws 280. Specifically, the hexagon socket head shoulder screws 280 pass through the aligned tool seat positioning holes 211, the corresponding support member positioning holes 2311 and the positioning sections 211B of the corresponding lower template positioning holes 211, and are threadedly coupled to the lower template positioning holes 211 Threaded segment 211A of hole 211. Therefore, the simultaneous positioning and fixing of multiple parts of the lower die assembly 20 is realized through the simple operation of positioning with one pin, which not only is easy to operate, fast to install, saves manpower, but also does not easily produce relative displacement between multiple parts, to ensure the punching accuracy.

Preferably, the support member 231 is made of aluminum alloy, which has the advantages of low cost, strong pressure bearing capacity, and long service life. Preferably, the cutting seat (also called "blade holder") 220 is stainless steel, such as stainless steel plate. It has the advantages of smooth surface, good mechanical strength, and corrosion resistance. This avoids the increase of errors due to deformation during compression, and prolongs the service life.

Next, the upper die assembly of the punching die 1 according to the present invention will be described with reference to FIGS. 4A and 4B. FIG. 4A shows the side of the upper mold assembly 10 facing the lower mold assembly 20. As shown in FIG. 4A, the upper die assembly 10 may include an upper die plate 110 and a blade (also referred to as "cutting plate") 120 fixed to the upper die plate 110. The upper plate 110 may be a rectangular plate with a certain thickness, and may include guide post guide sleeves 118 corresponding to the guide posts 218 of the lower die 210 at its four corners, so as to be sleeved during the punching process. On the guide post, precise guidance between the upper and lower die plates is achieved, thereby avoiding relative translation between the upper die assembly and the lower die assembly, and ensuring the precision of punching.

The upper die 110 may include a plurality of upper die positioning holes 111, and these upper template positioning holes 111 form an upper template positioning hole array, which is similar to the lower template positioning holes, so as to fit the blade 120 with different shapes.

The cutting plate 120 includes a blade edge 121 (FIG. 4B ) formed thereon. In a preferred embodiment, the cutting plate 120 and the blade 121 are integrally formed, as shown in the enlarged view of FIG . 4B . More preferably, the cutting plate 120 and the blade 121 are integrally formed by SKD11 cold working die steel through a numerically controlled machine (CNC). The cutting plate 120 and the blade 121 are heat-treated and quenched, and then CNC- finished again to avoid assembly errors. In particular, the cutting plate 120 and the blade 121 are formed by CNC machine tools, which is particularly advantageous when the part to be punched is a shaped part, because along the direction of the axis Z, the cutting plate 120 and the blade 121 are designed into any desired shape for the special-shaped part, such as arc surface, inclined surface, etc. which cannot be realized in the prior art, as described in detail below with reference to FIGS. 6 , 7A and 7B.

The punching die according to the present invention will be described first with reference to FIGS. 5A and 5B . FIG. 5A shows a cross-sectional side view of the upper die assembly 10 and the lower die assembly 20 of the punching die 1 after closing, and FIG. 5B shows an enlarged view of the part circled by detail A in FIG. 5A view. The upper die plate 110 is fastened together with the upper plate (not shown) of the die machine, for example, by bolts or pins, and it is not necessary to disassemble and replace the upper platen 110 when changing the knife seat and knife plate suitable for different products. The upper template 110 is fastened to the cutting plate 120 (eg by bolts or pins). The lower die plate 210 is fixed together with the machine table (not shown) of the die machine, for example by bolts or pins, and it is not necessary to disassemble and replace the lower die plate 210 when changing the cutter seat and cutter plate suitable for different products . When the upper die assembly 10 and the lower die assembly 20 are closed, the upper die plate 110 and the lower die plate 120 are guided and positioned by corresponding guide sleeves and guide posts, avoiding relative displacement between the upper and lower die plates. As a result, frequent retooling and calibration operations are not required, saving manpower and increasing productivity, as well as extending the service life of general-purpose molds.

Support 230 is constructed by the modular support 231, so that it can be adapted to any form of die. Since the lower die plate 210 has an array of positioning holes, it is also suitable for mounting brackets 230 of different shapes built by modular supports 231 thereon. In addition, the lower template, the bracket and the tool seat have positioning holes that can be aligned with each other, so that the same hexagonal inner hexagonal cylindrical head shoulder screw can pass through, eliminating the mutual positioning error between multiple components. The positioning of the upper template 110 and the blade 120 is similar.

Plates relative to the corresponding machine table is eliminated, and the positioning error of multiple parts in the upper die assembly and the lower die assembly is eliminated, the cutting edge 121 punches the part to be punched 90 with extremely high precision . This results in a satisfactory product of high quality.

Fig. 6 shows an example of a shaped part obtained by punching using the punching die according to the present invention. Fig. 7A shows the upper die assembly used for punching out the shaped part shown in Fig. 6, and Fig. 7B is an enlarged view of one of the units of the blade shown in Fig. 7A, for the sake of clarity out of its shape.

As shown in FIG. 6, the special-shaped member 80 has a substantially rectangular shape when viewed from a plan view, but its two long sides 81 and two short sides 82 are not located in the same plane, that is, its opening surface is a special-shaped part , wherein the heights of the two long sides 8 1 in the direction of the axis Z vary. As the forms of the packaged products in modern society are becoming more and more diversified, there are also various and different demands for special-shaped packaging. FIG. 6 only shows one example for illustration, and it should be understood that other forms of special-shaped parts are also within the scope of discussion of the present invention. As mentioned above, in the existing punching die, it is very difficult to obtain a satisfactory profiled part. On the one hand, manually bending a long-sized blade into a die blade can only form a flat edge, and due to the external force and its own stress during bending, the straightness of the formed die blade is also low. The accuracy of the die blade itself cannot be guaranteed. On the other hand, since the blade is made of wood or bakelite, a material with loose clearance and low strength, when the blade is embedded in the blade groove of the blade, the blade groove cannot correct the blade with existing errors, and the deformation will increase when subjected to high pressure, resulting in undesired deformation of the product. However, in the punching die according to the present invention, the special-shaped blade can be applied with lower cost and higher precision. An example of a profiled blade 120 is shown in FIG. 7A for punching out the profiled part as shown in FIG. 6. As shown, the blade 120 includes four units ( FIG. 7B ) , each unit is bent toward the lower template at both ends in the direction of the axis X, whereby the blade 121 fits the piece to be punched (not shown) of the special-shaped opening surface. The knife seat (not shown) has a matching form with the knife plate 120, and the part to be punched fits the knife seat, so during the process of punching, the part to be punched will not be greatly deformed, thereby obtaining high quality and high stability products. Moreover, the punching die according to the present invention can largely replace the metal die, but the production cycle is only about half of that of the metal die.

It should be understood that the structures described above and illustrated in the accompanying drawings are merely examples of the present invention, which may be replaced by other structures that perform the same or similar functions for obtaining the desired end result. Furthermore, it should be understood that the embodiments described above and shown in the accompanying drawings should be regarded as constituting only non-limiting examples of the invention, which may be modified in various ways within the scope of the patent claims.