CN112588950A

CN112588950A - Spring holding and carrying processing method

Info

Publication number: CN112588950A
Application number: CN202110097258.8A
Authority: CN
Inventors: 甘树德; 栾博语; 邓永强; 周涛; 王鸿; 甘琳巧; 罗鉴益; 黄琳琳
Original assignee: Chongqing University of Technology
Current assignee: Chongqing University of Technology
Priority date: 2021-01-25
Filing date: 2021-01-25
Publication date: 2021-04-02
Anticipated expiration: 2041-01-25
Also published as: CN112588950B

Abstract

The invention discloses a spring carrying processing method, during spring carrying processing, a belt material is fed by a feeding machine and then placed between a discharging plate and a lower template, and after sequentially passing through a first punching station, a second punching station, a third middle excess material blanking station, a fourth side excess material blanking station, a fifth workpiece end bending station, a sixth workpiece primary pre-bending station, a seventh workpiece secondary pre-bending station, an eighth workpiece primary bending station, a ninth workpiece rounding station and a tenth workpiece connecting excess material cutting station, the middle connecting excess material and the two side connecting excess materials of two workpieces in the belt material are cut, so that the two workpieces leak through a blanking hole.

Description

Spring holding and carrying processing method

Technical Field

The invention belongs to the field of circular part processing, and particularly relates to a spring carrying processing method.

Background

As shown in fig. 1, the applicant has devised a spring hanger having a mounting hole and two lightening holes, one end of the spring hanger passing through the mounting hole to form a circular hanger. At present, for the round workpiece, after the workpiece is blanked according to the expansion size of the workpiece, punching and rounding processes are performed on the blanked workpiece, and the processing mode has low forming efficiency and generates more waste. In practical production, after the material is cut into a strip shape, the strip material is fed to a progressive die through an automatic feeding machine, the strip material is punched, trimmed and pre-bent for multiple times, a core rod is inserted into a hollow part of a pre-bent workpiece through an air cylinder to perform a rounding operation, and finally, the prepared workpiece is trimmed and then blanked (for example, the chinese patent with the application number of 2013100324595).

Therefore, the efficiency is greatly improved by adopting the mode of processing the circular workpiece by the progressive die. However, in the workpiece forming process, the core rod for rounding the workpiece needs to be fed through the two cylinders, the rounding mode is complex, only one workpiece can be formed at one time, and the efficiency needs to be improved. Meanwhile, in the feeding process, the feeding speed of the belt material is controlled only through the feeding machine, the length change after bending in each working procedure cannot be realized, the difficulty in manufacturing the die is high, and the distance and the speed of each bending station are difficult to control.

Disclosure of Invention

Aiming at the defects of the prior art, the technical problems to be solved by the invention are as follows: how to provide a material-saving, simple-rounding and accurate-machining method for spring suspension.

In order to solve the technical problems, the invention adopts the following technical scheme:

a method for processing a spring arm, wherein the spring arm is provided with an assembly hole and two lightening holes, and one end of the spring arm penetrates through the assembly hole to form a circular arm, and the method is characterized by comprising the following steps of: s1, blanking, drawing a typesetting drawing processed by the spring carrying by CAD according to the unfolding length and the appearance of the spring carrying to be prepared, and then cutting the metal plate according to the width of the drawn typesetting drawing, wherein the cut metal belt is rectangular and the width is larger than the length of the spring carrying after unfolding; each station in the layout plate is correspondingly provided with two circular arms, and the width of each processing station is larger than the unfolding width of the two spring arms; s2, loading the metal strip into an automatic feeder, and feeding one end of the metal strip into a progressive die arranged on a pressure machine tool through the automatic feeder; s3, the metal strip is sequentially processed by the following steps from one side to the other side of the progressive die through the automatic feeder: a, punching, namely driving a punching male die on an upper die of a progressive die to punch downwards through a press machine, and punching lightening holes and assembling holes after the punching male die corresponds to a female die on a lower die of the progressive die; when punching, the punching is carried out in two stations, and the punching male dies and the punching female dies on the two stations are symmetrically arranged along the width direction of the metal strip; b, cutting edges of the punched belt material according to the unfolding width and the size of the spring arms, and successively blanking redundant waste materials in the middle and the outer sides of the two spring arm unfolding planes to form two spring arm unfolding planes connected in the middle; c, simultaneously bending two ends of the long sides of the two spring carrying planes; d, respectively bending two sides of the long sides of the two bent spring carrying planes twice to form two connected spring carrying bent arc parts; e, rounding the two spring carrying curved arc parts, wherein the rounding is finished by two stations of primary rounding and extrusion rounding, and when the primary rounding is finished, the workpiece is pressed down onto a lower mold core of the lower mold through a bent female mold insert of the upper mold, so that one end of the spring carrying curved arc parts passes through the two assembly holes, and then the primary rounding is finished; when the workpiece is extruded to be round, the slide wedges on the two sides of the lower die core are extruded to move oppositely through the inclined wedges on the upper die, and the workpiece which is initially rounded is extruded on the two sides of the lower die core to finish the round; f, simultaneously matching the middle connecting part and the two sides of the connecting part of the two rounded workpieces with the strip material by using a cutting male die and a cutting female die, and then shearing to enable the two workpieces to fall from a female die discharge hole of the cutting female die; when the connecting part of the middle parts of the two workpieces is cut off, the plate material of the connecting part cut off by the two workpieces is ejected out through the stripper in the upper die and the waste ejection nail arranged at the middle part of the cutting die and corresponding to the connecting part of the middle parts of the two workpieces, and the waste ejection nail is leaked and falls down from the discharge hole of the cutting die. Like this, draw the drawing of arranging the appearance according to work piece development picture and work piece appearance earlier, and then through punching a hole, cutting edge, tip bending, twice preflex, preliminary bend circle, cut off the junction after the whole circle to the metal strip material after, leak the work piece from the discharge hole and fall, work piece shaping speed is fast, and degree of automation is high. Meanwhile, during stock layout, the workpiece is punched twice, three holes of one workpiece are punched at each time, and the mode of punching twice can effectively reduce the impact on the strip in the punching process, reduce the deformation of the strip in the punching process and be beneficial to ensuring the strength of the strip after punching. Meanwhile, the three holes are completely opposite in direction, so that the minimum expected cutting after sample arrangement and edge cutting can be effectively guaranteed, the generation of waste materials is effectively reduced, and the processing cost of carrying is further reduced. When cutting the edge, cut the unnecessary rim charge in two work pieces middle parts earlier, cut the unnecessary rim charge of both sides again to can divide twice to cut the expansion appearance that forms two work pieces after, cut efficiently. The workpiece rounding is formed by primary rounding and rounding, during primary rounding, the pre-curved workpiece is pressed downwards by the curved female die insert and then is embraced at one end of the core die and passes through the assembly hole to form an irregular circular embracing arm, during rounding, the slide wedges are extruded by the inclined wedges, the two slide wedges are oppositely extruded to form the irregular circular embracing arm, and the irregular circular embracing arm is completely attached to the end part of the core die after extrusion to form a regular circular embracing arm.

Furthermore, when punching, two pilot holes are punched at intervals between the two processing stations and along the upper side and the lower side of the length direction of the metal strip, a plurality of pilot pins which are in one-to-one correspondence with the pilot holes are arranged in the progressive die, through holes which are in one-to-one correspondence with the pilot pins are arranged on the lower die of the progressive die, and the metal strip is guided and positioned on each processing station after the pilot pins correspond to the pilot holes on the metal strip. Like this, with the equidistant back of punching a hole of metal strip, control the position of each station through the interval between two adjacent holes, again with leading on the strip hole with upgrade in the mould lead the positive round pin cooperation back, can guarantee to lead positive round pin and lead the positive pore pair at the continuous antedisplacement in-process of metal strip, and then ensure the displacement distance of each metal strip to guarantee that each processing station corresponds correctly with the strip position, promote work piece machining precision.

Furthermore, two rows of strip guiding devices which are used for guiding the metal strips and jacking and returning the processed metal strips are also arranged in the lower die. Therefore, after the metal strip guiding devices are arranged, in the process of automatically feeding the metal strips by the automatic feeding mechanism, the metal strips move between the two rows of guiding devices all the time, so that the metal strips can be ensured to correspond to the processing male dies and the processing female dies in all stations after being fed, and the processing accuracy is further ensured.

Furthermore, each row of strip guiding devices consists of a plurality of floating top pins which are arranged at intervals and have the same direction with the processing direction of the metal strip, an annular clamping groove is arranged at the position, corresponding to the placement position of the metal strip to be processed, of each floating top pin, and each annular clamping groove of the two rows of floating top pins forms a strip forward positioning space for clamping the metal strip to be processed; the lower end of each floating ejector pin is provided with a return spring, and when the middle upper die of the progressive die moves upwards after being pressed downwards, the floating ejector pins lift the metal strip for a certain distance under the lifting action of the return springs, so that the lower end face of the metal strip returns to the initial processing height. Therefore, after the upper die presses the metal strip material with the press, the metal strip material is tightly attached to the upper die under the action of the downward pressure, meanwhile, the metal strip material and the floating top pin are pressed to move downwards, and the return spring is in a compressed state. After the processing of each station is accomplished, the press drives and goes up the mould and move, and there is no longer the holding down force metal strip material top, and then each superficial knock pin is at return spring's resilience back, gets back to initial height, makes under the metal strip material terminal surface and the lower mould terminal surface of processing between have a determining deviation to the autoloading mechanism of being convenient for drives metal strip material and continues to move to next station. The mode of this kind of adoption top floating pin jacking metal strip sets up simply, can ensure to have certain clearance between metal strip and the lower mould to the removal of metal strip of being convenient for. Meanwhile, the two rows of floating ejector pins are arranged, the metal belt materials can be effectively limited in the displacement direction after being clamped in the annular clamping grooves of the two rows of floating ejector pins, the metal belt materials are guaranteed to transversely move, and the metal belt materials correspond to the machining dies of the stations after moving. And after the floating top pins are arranged in two rows correspondingly, the balance of the lifting force of the metal strip can be ensured.

Furthermore, the lower mold core is a cylinder with the axial direction consistent with the length direction of the metal strip, the lower end of the lower mold core is provided with a mounting seat parallel to the lower mold core, the mounting seat is connected with the lower mold core through an upright post, a plurality of grooves are arranged at intervals at the lower end of the mounting seat, and a spring with the lower end penetrating into the lower end of the lower mold is arranged in each groove. Thus, the lower end of the lower die core is provided with the spring, and after the spring is additionally arranged, the spring can be used for coacting with the spring arranged below the floating top pin when the upper die has no pressure, so that the metal strip and the workpiece are supported and separated from the surface of the female die.

Furthermore, the middle part of the cutting female die is provided with a hollow part, the middle of the hollow part is provided with a partition plate which divides the hollow part into a left blanking hole and a right blanking hole, the middle part of the partition plate is provided with a rectangular cutting knife for cutting a connecting part between two workpieces, the upper end of the hollow part corresponds to the outer edge of the cutting male die in shape and size, and the inner edge of the hollow part is a cutting knife edge; the cutting male die and the partition plate are arranged in a crossed mode, the lower end of the cutting male die is provided with a groove matched with the partition plate of the cutting female die insert, and the outer edge of the cutting male die and the outer edge of the cutting female die insert are cutting edges through the groove; the waste ejection nail is arranged along the height direction of the partition board, a through hole for the waste ejection nail to penetrate is formed in the middle of the rectangular cutting knife and the partition board, and a jacking spring is arranged at the lower end of the waste ejection nail. Therefore, the cutting female die is divided into two parts by the partition plate, the two hollow parts respectively correspond to a machined workpiece, meanwhile, the connecting part of the workpiece and the metal strip comprises waste materials positioned on two sides of the workpiece and between the two workpieces, the waste materials in the middle part correspond to the rectangular cutting knife to be cut, and the waste materials on the two sides are cut by the cutting male die and the cutting blade of the cutting female die. After cutting, the waste materials on the two sides simultaneously fall down along with the cut workpiece through the hollow part, the connecting waste material on the middle part penetrates through the rectangular cutting knife through the ejector pin and then is ejected out, and the connecting waste material deviates to the hollow part on one side and then falls down. This setting can be ensured that two work pieces fall down simultaneously after the cutting, and avoid cutting back waste material to leave over on cutting off the die, influences cutting next time.

Drawings

FIG. 1 is a schematic perspective view of a spring hanger in an embodiment;

FIG. 2 is a layout of a processing row of the spring carrying in the embodiment;

FIG. 3 is a schematic view of the installation structure of the floating top pin and the pilot pin in the progressive die in the embodiment;

FIG. 4 is a schematic view showing the press-down working of the end of the workpiece at the fifth station in the example;

FIG. 5 is a schematic view illustrating a preliminary prebending process of a workpiece at a sixth station in the example;

FIG. 6 is a schematic diagram illustrating the secondary prebending of the workpiece at the seventh station in the example;

FIG. 7 is a schematic view illustrating the preliminary rounding of the workpiece at the eighth station in the embodiment;

FIG. 8 is a schematic view of the ninth working station of the embodiment for extruding and rounding workpieces;

FIG. 9 is a schematic view of a split structure of a cutting punch and a cutting die in the embodiment;

FIG. 10 is an enlarged view of the mounting structure of the cutting die in the embodiment.

Detailed Description

The invention is further illustrated with reference to the following figures and examples.

Example (b):

in the method for processing the spring carrier according to the embodiment, the spring carrier has an assembly hole and two lightening holes (as shown in fig. 1), and one end of the spring carrier passes through the assembly hole to form a circular carrier, which is characterized by comprising the following steps: s1, blanking, drawing a typesetting drawing (shown in figure 2) processed by the spring carrying by CAD according to the unfolding length and the appearance of the spring carrying to be prepared, cutting the metal coiled material into metal strip materials 1 according to the width of the drawn typesetting drawing, wherein the cut metal strip materials 1 are rectangular, and the width of the metal strip materials is larger than the length of the spring carrying after unfolding; each station in the layout plate is correspondingly provided with two circular arms, and the width of each processing station is larger than the unfolding width of the two spring arms; s2, loading the metal strip 1 into an automatic feeder, and feeding one end of the metal strip 1 into a progressive die arranged on a pressure machine tool through the automatic feeder; s3, the metal strip is sequentially processed by the following steps from one side to the other side of the progressive die through the automatic feeder: a, punching, namely driving a punching male die on an upper die of a progressive die to punch downwards through a press machine, and punching lightening holes and assembling holes after the punching male die corresponds to a female die on a lower die of the progressive die; when punching, the punching is carried out in two stations, and the punching male dies and the punching female dies on the two stations are symmetrically arranged along the width direction of the metal strip; b, cutting edges of the punched belt material according to the unfolding width and the size of the spring arms, and successively blanking redundant waste materials in the middle and the outer sides of the two spring arm unfolding planes to form two spring arm unfolding planes connected in the middle; c, simultaneously bending two ends of the long sides of the two spring carrying planes (as shown in fig. 4); d, respectively bending two sides of the long sides of the two bent spring carrying planes twice (as shown in fig. 5 and 6) to form two connected spring carrying curved parts; e, rounding the two spring carrying curved arc parts, wherein the rounding is finished by two stations of primary rounding and extrusion rounding, and during primary rounding, a workpiece is pressed down onto a lower die core 7 of a lower die through a bent die insert of an upper die, so that one end of the spring carrying curved arc part passes through the two assembly holes, and then the primary rounding is finished (as shown in fig. 7); when extruding and rounding, the slide wedges 6 on the two sides of the lower mold core 7 are extruded to move oppositely through the upper inclined wedge 5 of the upper mold, and the workpiece after preliminary rounding is extruded on the two sides of the lower mold core to complete rounding (as shown in figure 8); f, simultaneously matching the middle connecting part and the two sides of the two rounded workpieces with the strip material connecting part by using a cutting male die 8 and a cutting female die 9, and then shearing to enable the two workpieces to fall from a female die discharge hole of the cutting female die 9; when the connecting part between the middle parts of the two workpieces is cut off, the plate material of the connecting part cut off by the two workpieces is ejected out through the stripper plate in the upper die and the waste material ejector pin 10 which is arranged at the middle part of the cutting die 9 and corresponds to the connecting part between the middle parts of the two workpieces, and falls through the discharge hole of the cutting die (as shown in fig. 9 and 10).

As shown in fig. 2, in the typesetting of this embodiment, the spring holding is processed by ten stations, the male die and the female die adopted in the first station and the second station are the same, and six holes in total are punched in two workpieces in two stations by the cooperation of the punching male die and the punching female die. The third station punches the middle connecting position of two workpieces which are held in a hanging mode, redundant materials in the middle of the two workpieces are punched, the fourth station punches excess materials on two sides of the workpieces, the fifth station bends the two ends of the two workpieces downwards, the sixth station performs preliminary pre-bending on the two workpieces, the seventh station performs secondary pre-bending on the two workpieces, the eighth station performs preliminary rounding on the two workpieces, the ninth station performs rounding on the workpieces, and the tenth station cuts the middle connecting excess materials and the two side connecting excess materials of the two workpieces in the belt material to enable the two workpieces to leak through the blanking hole. And after the third station, the fourth station to the ninth station are provided with a corresponding bending male die, a corresponding bending female die, a corresponding cutting female die and a corresponding cutting male die at intervals of one station.

When punching, a plurality of pilot holes 11 are punched between the two processing stations and at the upper side and the lower side of the metal strip material 1 along the length direction at intervals, a plurality of pilot pins 2 which are in one-to-one correspondence with the pilot holes are arranged in the progressive die, through holes which are in one-to-one correspondence with the pilot pins 2 are arranged on the lower die of the progressive die, and the metal strip material 1 is guided and positioned on each processing station after corresponding to the pilot holes on the metal strip material through the pilot pins. The pilot hole 11 is formed by punching two pilot punching male dies which are symmetrically arranged at the first station.

Two rows of strip guiding devices (shown in figure 3) for guiding the metal strips and jacking and returning the processed metal strips are also arranged in the lower die. Each row of strip guiding devices consists of a plurality of floating top pins 3 which are arranged at intervals and have the same processing direction with the metal strips, an annular clamping groove is arranged at the position corresponding to the placement position of each floating top pin 3 and the metal strips 1 to be processed, and each annular clamping groove of the two rows of floating top pins 3 forms a strip forward-moving positioning space for clamping the metal strips to be processed; the lower end of each floating top pin 3 is provided with a return spring 4, and when the upper die in the progressive die moves upwards after being pressed downwards, the floating top pins 3 lift the metal strip 1 for a certain distance under the lifting action of the return springs 4, so that the lower end surface of the metal strip 1 returns to the primary processing height.

The lower mold core 7 is a cylinder with the axial direction consistent with the length direction of the metal strip, the lower end of the lower mold core 7 is provided with a mounting seat parallel to the lower mold core, the mounting seat is connected with the lower mold core in a matched mode through an upright post, a plurality of grooves are formed in the lower end of the mounting seat at intervals, and a spring with the lower end penetrating into the lower end of the lower mold is arranged in each groove.

The middle part of the cutting female die 9 in the embodiment is provided with a hollow part, the middle of the hollow part is provided with a partition plate 91 which divides the hollow part into a left blanking hole and a right blanking hole, the middle part of the partition plate 91 is provided with a rectangular cutting knife 92 for cutting a connecting part between two workpieces, the upper end of the hollow part corresponds to the shape and the size of the outer edge of the cutting male die 8, and the inner edge of the hollow part is a cutting knife edge; the cutting male die 8 and the partition plate 91 are arranged in a crossed manner, the lower end of the cutting male die 8 is provided with a groove matched with the partition plate 91 of the cutting female die insert 9, and the outer edge of the cut part and the outer edge of the cutting female die insert 9 are cutting edges by the groove; the waste ejection nail 10 is arranged along the height direction of the partition board 91, a through hole for the waste ejection nail 10 to penetrate is formed in the middle of the rectangular cutting knife 92 and the partition board 91, and a jacking spring is arranged at the lower end of the waste ejection nail 10.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the technical solutions, and although the present invention has been described in detail by referring to the preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of the present invention can be made without departing from the spirit and scope of the technical solutions, and all the modifications and equivalent substitutions should be covered by the claims of the present invention.

Claims

1. a processing method of a spring holding the shoulder, there is an assembly hole and two weight reduction holes on the spring holding the shoulder, and one end of the spring holding the shoulder passes through the assembly hole and forms a circular holding the shoulder, it is characterized in that comprising: The following steps: S1, cutting the material, drawing the layout diagram of the spring hugging processing with CAD according to the unfolded length and shape of the spring hugging to be prepared, and then cutting the metal coil into metal strips according to the width of the drawn layout drawing (1 ), the cut metal strip (1) is rectangular, and its width is greater than the length of the spring arm after unfolding; in the layout diagram, each station corresponds to two circular arms, and the width of each processing station is Greater than the unfolded width of the two springs; S2, load the metal strip (1) into the automatic feeder, and send one end of the metal strip (1) into the progressive die installed on the press machine through the automatic feeder; S3, pass the metal strip through the automatic feeder from one side of the progressive die to the other side in turn through the following processes: a. Punching holes, the punching punch on the upper die of the progressive die is driven down by the press, and punched downward with the progressive die. After the concave die on the lower die is corresponding to the die, punch out the weight-reducing hole and the assembly hole; when punching, the punching is carried out in two stations, and the punching punch and punching die on the two stations are along the width of the metal strip. The directions are set symmetrically; b, according to the unfolded width and size of the spring sling, trim the edges of the punched tape. When cutting the edges, punch out the excess waste in the middle and the outer side of the unfolding plane of the two spring slings successively to form two middle parts connected to each other. The spring hugging and unfolding plane; c, simultaneously bending both ends of the long sides of the two spring hugging planes; d, bending the two sides of the long sides of the two spring hugging planes after being bent in two separate arcs to form Two connected springs hugging and bending the curved parts; e, performing a complete circle on the two springs hugging and bending the curved parts, and the complete circle is completed by two stations of preliminary rounding and extruding the full circle. The bending concave die insert of the upper die presses the workpiece onto the lower die core (7) of the lower die, so that the end of the spring hugging passes through the two assembly holes to complete the preliminary round; The upper wedge (5) squeezes the sliding wedges (6) on both sides of the lower die core (7) to move toward each other, and squeezes the preliminarily rounded workpiece on both sides of the lower die core to complete the complete circle; f. The connected part in the middle of the rounded workpiece and the parts connected with the strip on both sides are simultaneously cut with the cutting punch (8) and the cutting die (9) and then cut, so that the two workpieces are cut from the die row of the cutting die (9). The material hole falls; while cutting off the connecting part in the middle of the two workpieces, it passes through the stripper plate in the upper die and a scrap top nail (10) arranged in the middle of the cutting die (9) and corresponding to the connecting part of the middle part of the two workpieces. ) pushes out the connecting part of the two workpieces, and leaks down from the discharge hole of the cutting die.

2. The processing method of the spring hugging according to claim 1, characterized in that, during punching, punching is also performed at intervals between the two processing stations and on the upper and lower sides along the length direction of the metal strip (1). There are a plurality of guide holes (11), a plurality of guide pins (2) corresponding to the guide holes one-to-one in the progressive die, and a guide pin (2) on the lower die of the progressive die. ) one-to-one corresponding perforation, the metal strip (1) guides and locates each processing station after corresponding to the guide holes on the metal strip through the guide pins.

3. The processing method of the spring hugging according to claim 1 or 2, wherein two rows of belts for guiding the metal strip and lifting and returning the processed metal strip are also provided in the lower die. Material guide device.

4. The method for processing a spring hugging shoulder according to claim 3, characterized in that, each row of strip guide devices is composed of a plurality of floating top pins (3) arranged at intervals and consistent with the processing direction of the metal strip. Each floating top pin (3) is provided with an annular clamping groove corresponding to the position where the metal strip (1) to be processed is placed, and each annular clamping groove of the two rows of floating top pins (3) forms an annular clamping groove for clamping the to-be-processed metal strip (1). There is a space for positioning the metal strip in the forward direction of the strip material; a return spring (4) is provided at the lower end of each floating top pin (3). 3) Under the lifting action of the return spring (4), the metal strip (1) is lifted for a certain distance, so that the lower end surface of the metal strip (1) returns to the initial processing height.

5. The processing method of the spring hugging according to claim 1, characterized in that, the lower mold core (7) is a cylinder whose axial direction is consistent with the length direction of the metal strip, and the lower mold core (7) There is a mounting seat parallel to the lower end of the mounting seat, the mounting seat and the lower mold core are connected by a column, and a plurality of grooves are spaced at the lower end of the mounting seat, and each groove is provided with a A spring whose lower end penetrates into the lower end of the lower die.

6 . The processing method of the spring hugging according to claim 1 , wherein the cutting die ( 9 ) has a hollow part in the middle, and a hollow part is arranged in the middle of the hollow part. 7 . A partition (91) is divided into a left blanking hole and a right blanking hole, and a rectangular cutting knife (92) is arranged in the middle of the partition (91) for cutting the intermediate connecting part of the two workpieces. The upper end of the hollow part is Corresponding to the shape and size of the outer edge of the cutting punch (8), and the inner edge of the hollow portion is a cutting blade; the cutting punch (8) and the partition plate (91) are arranged in an intersection, and the cutting punch (8) The lower end has a groove matched with the partition plate (91) of the cutting die insert (9), and the outer edge of the groove to be cut and the outer edge of the cutting die insert (9) are both cutting edges; The waste top nail (10) is arranged along the height direction of the partition plate (91), and a through hole for the waste top nail (10) to pass through is provided in the middle of the rectangular cutting knife (92) and in the partition plate (91). The lower end of the top nail (10) is provided with a lifting spring.