Square tube punching die

Abstract

The invention relates to the technical field of punching of pipe fittings, in particular to a square pipe punching die. Comprising an automatic feeding and discharging mechanism and a punching mechanism, one end of a square tube is fixedly connected with the automatic feeding and discharging mechanism, and the other end of the square tube is arranged in the punching mechanism; the punching mechanism comprises a through hole punching needle and a non-through hole punching needle, the non-through hole punching needle is fixed on a punching needle fixing plate, and the punching needle fixing plate is fixedly connected with the upper die plate; the middle plate is fixedly connected with the upper die plate, a blocking plate groove is formed in the middle plate, the through hole punching needle blocking plate is arranged in the blocking plate groove in a sliding mode, a first through hole is formed in the through hole punching needle blocking plate, a through hole punching needle sliding groove is correspondingly formed in the portion, below the blocking plate groove, of the middle plate, and the upper portion of the through hole punching needle is movably arranged in the through hole punching needle sliding groove. And the through hole punching needle is in clearance fit with the first through hole. According to the square tube punching device, through hole punching operation and non-through hole punching operation of a square tube can be conducted at the same time, the punching efficiency of the square tube is improved, and the structure of the square tube punching device is simplified.

Description

Technical Field

[0001] The present invention relates to the technical field of punching of pipe fittings, and in particular to a square pipe punching die. Background Art

[0002] A square pipe is a pipe with a square cross-section. Most common square pipes are made of steel pipes. In some cases, it is necessary to punch holes in the square pipes. At present, for the square pipe punching process, the traditional method of using a punching press for punching is usually adopted. The punching of square pipes includes through-hole punching and non-through-hole punching.

[0003] In the currently common punching processes, when the holes on the square pipe are evenly distributed, they can be clamped and punched at one time.

[0004] When the holes on the square pipe are unevenly distributed, the square pipe needs to be clamped and positioned twice: during the first clamping and positioning process, non-through-hole punching is realized, and during the second clamping and positioning process, through-hole punching is realized. The problems existing are: (1) The punching efficiency of the square pipe will be greatly reduced due to the two clamping and positioning operations; (2) Errors are bound to occur during the two positioning processes. The positioning errors will directly affect the punching accuracy, thereby reducing the punching precision. When the error is serious and inaccurate, it will directly lead to the scrapping of the square pipe. Summary of the Invention

[0005] The purpose of the present invention is to overcome the above-mentioned defects existing in the prior art, and propose a square pipe punching die, which realizes the simultaneous through-hole punching operation and non-through-hole punching operation of the square pipe, realizes the one-time clamping and punching of the square pipe with unevenly distributed holes, improves the punching efficiency and punching precision of the square pipe, and simplifies the structure of the square pipe punching device.

[0006] The technical solution of the present invention is: a square pipe punching die, which includes an automatic feeding and discharging mechanism and a punching mechanism. One end of the square pipe is fixedly connected to the automatic feeding and discharging mechanism, and the other end of the square pipe is arranged inside the punching mechanism;

[0007] The punching mechanism includes a through-hole punching needle and a non-through-hole punching needle. The non-through-hole punching needle is fixed on the punching needle fixing plate, and the punching needle fixing plate is fixedly connected to the upper template;

[0008] The middle plate is fixedly connected to the upper template. A plug plate groove is arranged inside the middle plate. The through-hole punching needle plug plate is slidably arranged in the plug plate groove. A first through-hole is arranged inside the through-hole punching needle plug plate. A corresponding through-hole punching needle sliding groove is arranged inside the middle plate below the plug plate groove. The upper part of the through-hole punching needle is movably arranged in the through-hole punching needle sliding groove. The through-hole punching needle and the first through-hole are in clearance fit;

[0009] When the first through hole and the through hole punch chute are in a misaligned state, the through hole punch completes the through hole, and at this time, punching of both through holes and non-through holes can be achieved simultaneously; when the first through hole and the through hole punch chute are vertically connected, the through hole punch enters the first through hole, and at this time, only punching of non-through holes is achieved.

[0010] In the present invention, the automatic feeding and discharging mechanism includes:

[0011] A first cylinder, whose cylinder body is connected to the moving part;

[0012] A movable plate, fixedly connected to the telescopic rod of the first cylinder, and a groove is provided on the side of the movable plate facing the punching mechanism;

[0013] A crank, whose upper end is connected to the end of the telescopic rod of the first cylinder, and a upper pressing claw is fixed at the bottom end. The lower end of the crank is arranged in the groove and is rotatably connected to the groove wall;

[0014] The upper pressing claw is located above the square tube;

[0015] A lower pressing claw, fixedly connected to the movable plate, and located below the inner side surface of the upper wall of the square tube.

[0016] The moving part includes:

[0017] A moving bracket, including a cylinder fixing plate and sliding plates located on both symmetric sides of the cylinder fixing plate. The cylinder fixing plate is fixedly connected to the sliding plates on both sides;

[0018] A gear, meshing with a rack, and the rack is fixed on one of the sliding plates;

[0019] A machine tool guide rail is located below the sliding plate, and the machine tool guide rail is slidably connected to the sliding plate.

[0020] The punching mechanism includes:

[0021] An upper template, on whose lower surface, a top plate, a middle plate, and a punch fixing plate are fixedly connected in sequence. Several workpiece locking columns are fixed on the top plate, and non-through hole punches and positioning punches are fixed on the punch fixing plate;

[0022] A lower template, on whose upper surface, a die blank and a punch guide plate are fixedly connected from bottom to top. The square tube is arranged in the die blank, and the through hole punch, the non-through hole punch, and the workpiece locking column penetrate through the punch guide plate;

[0023] A ball bushing guide post, whose bottom end is fixedly connected to the lower template, and whose upper end is movably connected to the upper template.

[0024] The ball bushing guide post includes:

[0025] The guiding column has its bottom end fixedly connected to the lower template, and an upper template limiting disc is fixed at the top end. A ball guide sleeve is slidably sleeved on its upper end, and several rolling balls are arranged inside the ball guide sleeve;

[0026] The outer steel sleeve is fixed inside the upper template and is located on the annular outer side of the ball guide sleeve. A sliding friction exists between the ball guide sleeve and the balls of the outer steel sleeve. During the downward movement of the outer steel sleeve, the ball guide sleeve is driven to move downward through rolling friction;

[0027] The first spring is wound around the annular outer side of the guiding column. One end of it contacts the ball guide sleeve, and the other end contacts the lower template.

[0028] A plug plate groove is provided in the middle plate and is perpendicular to the length direction of the square tube. One end of the through-hole punching needle plug plate is connected to the second cylinder.

[0029] A groove along the length direction of the square tube is provided inside the die blank, and the part of the square tube to be punched is arranged in the groove;

[0030] Two locking blocks are provided in each groove, and the square tube is located between the two locking blocks;

[0031] An arc-shaped groove is provided on the side wall of the locking block facing the groove. Correspondingly, an arc-shaped groove is provided on the inner wall of the die blank. The arc-shaped groove of the locking block and the arc-shaped groove on the inner wall of the die blank form a cylindrical groove, and an interference fit exists between the locking block and the cylindrical groove.

[0032] Adjusting jackscrews are respectively provided at the two symmetrical outer side walls of the die blank. Corresponding threaded holes are provided inside the locking blocks, and smooth holes are provided inside the die blank. The inner end of the adjusting jackscrew is threadedly connected to the locking block, and the adjusting jackscrew is movably connected to the die blank;

[0033] A second spring is connected between the outer end of the adjusting jackscrew and the die blank, and the second spring is wound around the annular outer side of the adjusting jackscrew.

[0034] An punching and blanking bottom die is provided on the bottom surface of the die blank directly below the through-hole punching needle. A blanking through-hole is provided on the punching and blanking bottom die, and the blanking through-hole is a tapered groove hole with a smaller upper part and a larger lower part.

[0035] The beneficial effects of the present invention are as follows:

[0036] (1) Through the automatic feeding and discharging mechanism, the automatic feeding and discharging of the square tube are realized. The feeding and discharging process of the square tube is realized through the automatic feeding and discharging mechanism, without manual operation. Cooperating with the PLC control system, the accurate feeding of the square tube is realized;

[0037] (2) The automatic feeding and discharging mechanism adopts the structure of a crank, an upper pressing claw and a lower pressing claw, realizing the clamping and fixing of the square tube by the automatic feeding and discharging mechanism, and improving the clamping and fixing effect on the square tube;

[0038] (3) Through the punching mechanism, it is possible to simultaneously punch through holes and non-through holes in the square pipe, improving the punching efficiency of the square pipe: When only non-through hole punching of the square pipe is required, move the through hole punch plug plate. The square pipe exerts an upward thrust on the bottom of the through hole punch, causing the upper end of the through hole punch to move upward into the through hole punch plug plate. At this time, only the non-through hole punch punches the non-through hole in the square pipe; When through hole punching of the square pipe is required, use the through hole punch plug plate to limit the through hole punch to achieve the through hole punching operation of the square pipe. At this time, it is possible to simultaneously punch through holes and non-through holes in the square pipe;

[0039] (4) This application realizes punching various forms of holes in the square pipe, and can not only achieve one-time clamping punching of uniformly distributed holes, but also achieve one-time clamping punching of non-uniformly distributed holes, improving the punching efficiency and punching accuracy of the square pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a three-dimensional structural schematic diagram of the present invention;

[0041] Figure 2 is a top view structural schematic diagram of the present invention;

[0042] Figure 3 is a partial enlarged structural schematic diagram of the upper clamping jaw and the lower clamping jaw;

[0043] Figure 4 is an exploded structural schematic diagram of the punching mechanism;

[0044] Figure 5 is a structural schematic diagram of the ball bushing and guide pillar;

[0045] Figure 6 is a structural schematic diagram when the locking block and the locking column clamp the square pipe;

[0046] Figure 7 is a structural schematic diagram of the die blank;

[0047] Figure 8 is a structural schematic diagram of the square pipe and the punch;

[0048] Figure 9 is a structural schematic diagram of the square pipe after punching in this embodiment;

[0049] Figure 10 is a structural schematic diagram at the die core;

[0050] Figure 11 is a structural schematic diagram of the punch fixing plate;

[0051] Figure 12 is a structural schematic diagram of the middle plate;

[0052] Figure 13It is a schematic structural diagram of the through-hole punch needle.

[0053] In the figure: 1 oil cylinder connecting sleeve; 2 upper template limit disc; 3 upper template; 4 top plate; 5 middle plate; 6 punch needle fixing plate; 7 punch needle guide plate; 8 square tube; 9 positioning punch needle; 10 die blank; 11 locking block; 12 guide post; 13 first spring; 14 ball bushing; 15 adjusting set screw; 16 blind hole punch needle; 17 lower template; 18 workpiece locking post; 19 machine tool guide rail; 20 sliding plate; 21 pull rod; 22 rack; 23 gear; 24 motor; 25 vertical frame; 26 first cylinder; 27 crank; 28 lower pressing claw; 29 upper pressing claw; 30 through-hole punch needle; 34 ball bushing guide post; 35 fulcrum; 36 moving support; 37 cylinder fixing plate; 39 outer steel sleeve; 40 circular arc locking hole; 41 second spring; 43 punching and blanking bottom die; 44 die core; 45 punch needle inner die; 46 positioning punch needle inner die; 47 locking post hole; 48 blind hole punch needle fixing hole; 49 through-hole punch needle hole; 50 limit support block; 51 second cylinder; 52 through-hole punch needle plug plate; 53 plug plate groove; 54 movable plate; 55 blind hole; 56 through hole. Specific embodiments

[0054] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0055] In the following description, specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0056] As Figure 1 shown, the square tube punching die of the present invention includes an automatic feeding and discharging mechanism and a punching mechanism. One end of the square tube is arranged in the punching mechanism, and the punching action on the square tube is completed through the punching mechanism. The other end of the square tube is connected to the automatic feeding and discharging mechanism, and the feeding of the square tube during the punching process is realized through the automatic feeding and discharging mechanism.

[0057] As Figures 1 to 3 shown, the automatic feeding and discharging mechanism includes a first cylinder 26, a crank 27, an upper pressing claw 29 and a lower pressing claw 28. The cylinder body of the first cylinder 26 is fixed on the vertical frame 25. The telescopic rod of the first cylinder 26 is arranged towards the punching mechanism, and a crank 27 is hinged to the end of the telescopic rod. The crank 27 is arc-shaped. The upper end of the crank 27 is hinged to the end of the telescopic rod, and the bottom end of the crank 27 is welded and fixed with an upper pressing claw 29. The bottom surface of the upper pressing claw 29 is corrugated.

[0058] The telescopic rod of the first cylinder 26 is fixedly connected to the movable plate 54. The lower part of the crank 27 is hinged to the movable plate 54. A downward pressing claw 28 is fixedly connected to one side of the movable plate 54 facing the stamping mechanism. The top surface of the downward pressing claw 28 is corrugated. The upward pressing claw 29 is located above the wall of the square tube, and the downward pressing claw 28 is located below the wall of the square tube. The square tube 8 is fixedly clamped by the clamping between the upward pressing claw 29 and the downward pressing claw 28.

[0059] In this embodiment, the movable plate 54 includes a vertical plate and a horizontal plate that are vertically and fixedly connected. The vertical plate is fixedly connected to the telescopic rod of the first cylinder 26. A groove is provided in the middle of the side of the horizontal plate facing the stamping mechanism. The lower part of the crank 27 is arranged in the groove and is rotationally connected to the side wall of the groove through a rotating shaft. An upward pressing claw 29 is fixed to the bottom of the crank 27. Downward pressing claws 28 are respectively fixed below the horizontal plates on both sides of the upward pressing claw 29. The two downward pressing claws 28 are respectively inserted into the square tubes 8 on both sides, and the upward pressing claw 29 is located above the square tubes 8 on both sides.

[0060] During the operation of the first cylinder 26, when the telescopic rod of the first cylinder 26 moves, it drives the crank 27 connected thereto to rotate around the connection rotating shaft between the crank and the movable plate 44. During the rotation of the crank 27, the upward and downward movement of the upward pressing claw 29 fixed to the bottom of the crank 27 is realized. In this embodiment, when the telescopic rod of the first cylinder 26 extends, it drives the crank 27 to rotate counterclockwise around the rotating shaft. At this time, the upward pressing claw 29 fixed to the bottom of the crank 27 moves downward, thereby realizing the clamping and fixing of the end of the square tube. When the telescopic rod of the first cylinder 26 retracts, it drives the crank 27 to rotate clockwise around the rotating shaft. At this time, the upward pressing claw 29 fixed to the bottom of the crank 27 moves upward to release the square tube.

[0061] In this application, the vertical frame 25 is connected to the moving bracket 36, and the moving bracket 36 is connected to the moving part. During the movement of the moving bracket 36 driven by the moving part, the reciprocating movement of the first cylinder 26 is realized, so as to push the upward pressing claw and the downward pressing claw to the end of the square tube.

[0062] The moving bracket 36 includes a cylinder fixing plate 37 in the middle and sliding plates 20 located on both symmetric sides of the cylinder fixing plate 37. The sliding plates 20 are fixedly connected to the two side walls of the cylinder fixing plate 37, and the vertical frame 25 is fixed on the cylinder fixing plate 37. One of the sliding plates 20 is connected to the moving part. During the movement of the moving part driving the connected sliding plate 20, it drives the cylinder fixing plate 37 and the first cylinder 26 arranged on the cylinder fixing plate 37 to reciprocate. At this time, the other sliding plate 20 plays a guiding role.

[0063] The moving part includes a gear 23, a rack 22, and a machine tool guide rail 19. A sliding connection is formed between the cross slide 20 and the machine tool guide rail 19 below it. In this embodiment, a groove is provided on the bottom surface of the cross slide 20, and a protrusion is provided on the corresponding machine tool guide rail 19. The protrusion is slidably arranged in the groove, thereby realizing the sliding connection between the cross slide 20 and the machine tool guide rail 19. At the same time, a rack 22 is provided on the cross slide 20, and the gear 23 meshes with the rack 22. When the motor 24 operates to drive the gear 23 to rotate, through the meshing between the gear 23 and the rack 22, the rack 22 and the cross slide 20 fixedly connected to the rack 22 are driven to reciprocate. During the reciprocating movement of the cross slide 20, the machine tool guide rail 19 plays a guiding role.

[0064] During the process that the moving part drives the cross slide on this side connected to it to reciprocate along the machine tool guide rail, the cross slide on the other side also reciprocates along the machine tool guide rail with which it is slidably connected. Through the cross slides on both sides, the reciprocating movement of the cylinder fixing plate 37 and the first cylinder 26 is guided.

[0065] As Figure 1 and Figure 4 As shown, the punching mechanism includes an upper template 3, a lower template 17, and a ball bushing guide post 34 connecting the upper template 3 and the lower template 17. In this embodiment, the upper template 3 and the lower template 17 are in the shape of a tetrahedral plate. Therefore, the upper template 3 and the lower template 17 are connected by ball bushing guide posts 34 located at four corner points. The bottom end of the ball bushing guide post 34 is fixedly connected to the lower template 17, and a sliding connection is formed between the upper end of the ball bushing guide post 34 and the upper template 3. A cylinder connecting sleeve 1 is fixed in the middle of the top surface of the upper template 3. The connection with an external cylinder is realized through the cylinder connecting sleeve, and the upper template 3 is driven to move up and down by the external cylinder. When the external cylinder applies a downward force to the upper template 3, the upper template 3 moves downward. The upper template 3 drives the through-hole punch pin and the blind-hole punch pin connected to it to move downward. During the movement, the punching operations for the through holes and blind holes of the square tube are realized. When the external cylinder applies an upward force to the upper template 3, the upper template 3 drives the through-hole punch pin and the blind-hole punch pin to move upward.

[0066] As Figure 5 As shown, the ball bushing guide post 34 includes a guide post 12. The bottom end of the guide post 12 is fixedly connected to the lower template 17. A ball bushing 14 is slidably sleeved on the upper end of the guide post 12. Several rollable balls are provided in the ball bushing 14. An outer steel sleeve 39 is provided on the annular outer side of the ball bushing 14. A sliding friction is formed between the outer steel sleeve 39 and the balls in the ball bushing. Through this rolling friction, when the outer steel sleeve 39 moves downward, the ball bushing 14 is driven to move downward along the guide post 12. Through the balls in the ball bushing 14, the friction force between the outer steel sleeve 39 and the ball bushing 14 can be reduced. The outer steel sleeve 39 is fixedly connected to the upper template 3.

[0067] The top end of the guide post 12 is fixed with an upper template limit disk 2, and the upper template limit disk 2 is located above the outer steel sleeve 39. During the lifting and lowering process of the outer steel sleeve 39 with the upper template 3, the guide post 12 plays a role in limiting and guiding the lifting and lowering movement of the upper template 3, ensuring that the upper template 3 is always directly above the lower template 17. The upper template limit disk 2 prevents the upper template 3 from detaching from the ball bushing guide post 34 and plays a blocking role for the upper template 3.

[0068] A first spring 13 is provided between the ball bushing 14 and the lower template 17, and the first spring 13 is wound around the outside of the guide post 12. During the downward movement of the outer steel sleeve 39 with the upper template 3, the ball bushing 14 is driven to move downward through sliding friction, and the first spring 13 is compressed by the ball bushing 14 to generate a compressive force. When the downward pressure applied to the upper template 3 is removed, under the elastic force of the first spring 13, the ball bushing 14 automatically resets and pushes the outer steel sleeve 39 and the upper template 3 to automatically reset.

[0069] As Figure 4 shown, a top plate 4, a middle plate 5, and a punch needle fixing plate 6 are successively fixed below the upper template 3. The workpiece locking post 18 is fixed on the top plate 4. Through holes for punch needles are provided on the middle plate 5. A positioning punch needle and a blind hole punch needle are fixed on the punch needle fixing plate 6. A die blank 10 is fixed on the lower template 17, and a punch needle guide plate 7 is fixed on the top surface of the die blank 10.

[0070] The top end of the workpiece locking post 18 is fixedly connected to the top plate 4, and the lower end successively passes through the middle plate 5, the punch needle fixing plate 6, the punch needle guide plate 7, and is inserted into the die blank 10, playing a locking role for the square tube.

[0071] The top end of the through hole punch needle is movably arranged in the middle plate 5, and the top plate 4 plays a limiting role for the top end of the through hole punch needle. The lower end of the through hole punch needle successively passes through the middle plate 5, the punch needle fixing plate 6, the punch needle guide plate 7, and acts on the square tube in the die blank 10 to realize through hole punching of the square tube.

[0072] The top end of the positioning punch needle is fixedly connected to the punch needle fixing plate 6, and the lower end of the positioning punch needle successively passes through the middle plate 5, the punch needle fixing plate 6, the punch needle guide plate 7, and acts on the square tube in the die blank 10 to realize positioning of the square tube.

[0073] The top end of the blind hole punch needle is fixedly connected to the punch needle fixing plate 6, and the lower end of the blind hole punch needle successively passes through the middle plate 5, the punch needle fixing plate 6, the punch needle guide plate 7, and acts on the square tube in the die blank 10 to realize blind hole punching of the square tube.

[0074] In this embodiment, the top plate 4 is in the shape of a tetrahedral plate, and workpiece locking posts 18 are respectively fixed at the four corner points of the top plate 4.

[0075] As Figure 12 and Figure 13As shown, the middle plate 5 is in the shape of a tetrahedral plate. Inside the middle plate 5 and perpendicular to the length direction of the square pipe, there is a plug plate groove 53. Inside the plug plate groove 53, there is a through-hole punching needle plug plate 52. The through-hole punching needle plug plate 52 is movably arranged in the plug plate groove 53, that is, the through-hole punching needle plug plate 52 can reciprocate in the plug plate groove 53. One end of the through-hole punching needle plug plate 52 is connected to the second cylinder 51. During the operation of the second cylinder 51, it can drive the through-hole punching needle plug plate 52 to reciprocate in the plug plate groove 53.

[0076] Inside the middle plate below the plug plate groove 53, several vertically arranged through-hole punching needle sliding grooves are arranged at intervals. The through-hole punching needle 30 is movably arranged in the through-hole punching needle sliding grooves. Correspondingly, several vertical first through-holes are also arranged at intervals in the through-hole punching needle plug plate 52. There is a clearance fit between the through-hole punching needle 30 and the first through-holes. The number of the first through-holes and the through-hole punching needle sliding grooves is mainly determined by the number of square pipes inside the die blank. In this embodiment, when there are two square pipes inside the die blank, it means that punching of two square pipes needs to be realized simultaneously. At this time, two through-hole punching needle sliding grooves are arranged at intervals at the bottom of the plug plate groove 53, and two first through-holes are arranged at intervals in the through-hole punching needle plug plate 52.

[0077] During the movement of the through-hole punching needle plug plate 52 in the plug plate groove 53, when the first through-hole in the through-hole punching needle plug plate 52 is exactly aligned with the through-hole punching needle sliding groove below it, there is no obstruction above the through-hole punching needle 3. At this time, the through-hole punching needle 30 in the through-hole punching needle sliding groove moves upward under the pushing action of the square pipe and enters the first through-hole in the through-hole punching needle plug plate 52. At this time, the through-hole punching needle is in a free state and will not generate an impact force on the square pipe. At this time, there is no need to complete the through-hole punching of the square pipe.

[0078] When through-hole punching of the square pipe is required, first, when the upper template rises, under the action of its own gravity, the through-hole punching needle automatically falls from the first through-hole of the through-hole punching needle plug plate 52 into the through-hole punching needle sliding groove; then, the second cylinder 51 drives the through-hole punching needle plug plate 52 to move in the plug plate groove 53, causing a dislocation between the first through-hole in the through-hole punching needle plug plate 52 and the through-hole punching needle sliding groove at the bottom of the plug plate groove 53. At this time, the through-hole punching needle 30 is located below the through-hole punching needle plug plate 52, and the through-hole punching needle plug plate 52 blocks the through-hole punching needle 30 in the through-hole punching needle sliding groove, preventing the through-hole punching needle 30 from moving upward; finally, under the action of the external oil cylinder, the lower template moves downward. The lower template drives the through-hole punching needle to move downward. Under the action of the punching force, the square pipe wall is subjected to the shearing force and extrusion force at the edge of the through-hole punching needle and the punching needle inner die 45, completing the through-hole punching operation. While the lower template moves downward, it also drives the blind-hole punching needle to move downward. Under the action of the punching force, the blind-hole punching operation of the square pipe wall is completed.

[0079] As Figure 4As shown, the punch needle fixing plate 6 is in the shape of a tetrahedral plate. Along the length direction of the square tube, several rows of punch needle connection holes are provided on the punch needle fixing plate 6. The punch needle fixing plate 6 is fixedly connected to the blind hole punch needle 16 and the positioning punch needle 9 through these punch needle connection holes. The number of rows of punch needle connection holes is determined by the number of square tubes in the die blank. In this embodiment, when there are two square tubes in the die blank, it means that punching of two square tubes needs to be achieved simultaneously. At this time, two rows of punch needle connection holes are provided on the punch needle fixing plate 6.

[0080] As Figure 11 shown, locking post holes 47 are respectively provided at the four corner points of the punch needle fixing plate 6. The workpiece locking post 18 passes through the locking post holes 47, and the workpiece locking post 18 is movably arranged in the locking post holes 47. Blind hole punch needle fixing holes 48 are provided on the punch needle fixing plate 6. The top end of the blind hole punch needle is fixed in the blind hole punch needle fixing holes 48. Through hole punch needle holes 49 are also provided on the punch needle fixing plate 6. The through hole punch needle passes through the through hole punch needle holes 49, and the through hole punch needle is movably arranged in the through hole punch needle holes 49. Several limiting support blocks 50 are also fixedly connected to the bottom surface of the punch needle fixing plate 6. In this embodiment, the limiting support blocks 50 are fixedly connected to the punch needle fixing plate 6 through bolts. When the upper template 3, the top plate 4, the middle plate 5, and the punch needle fixing plate 6 accidentally fall, the limiting support blocks 50 can effectively prevent the punch needle guide plate from being damaged due to the fall.

[0081] As Figure 8 shown, in this embodiment, two positioning punch needles 9, four blind hole punch needles 16, and one through hole punch needle 30 are respectively provided above each square tube 8. Among them, the positioning punch needle 9 realizes the positioning of the square tube 8 during the punching process, the blind hole punch needle 16 realizes the punching of the upper side wall of the square tube 8, and the through hole punch needle 30 realizes the punching of the upper side wall and the lower side wall of the square tube 8.

[0082] The square tube after punching by the mold described in this embodiment is as Figure 9 shown. Through holes 56 and blind holes 55 are provided on the square tube, and the through holes 56 and the blind holes 55 are unevenly arranged. Four blind holes 55 are provided at the leftmost side of the square tube, and there are twelve blind holes 55 between two adjacent through holes 56.

[0083] Through analysis of the punching process, it can be known that first, the four blind hole punch needles 16 and one through hole punch needle 30 described in this embodiment are used to simultaneously perform blind hole punching and through hole punching on the square tube.

[0084] Next, the four blind hole punch needles 16 are used to perform blind hole punching on the square tube twice respectively. At this time, through hole punching is not performed on the square tube; then, the four blind hole punch needles 16 and one through hole punch needle 30 are used to perform blind hole punching and through hole punching on the square tube again. Then the above punching operations are repeated to achieve punching of the square tube.

[0085] In this application, the setting methods of the positioning punch, blind hole punch, and through hole punch are not limited to the forms disclosed in this embodiment. The positions where each punch is set and the selected content need to be determined according to the actual punching requirements of the square tube.

[0086] As Figure 10 shown, a die core 44 is provided inside the square tube 8. The die core 44 plays a guiding and limiting role for the square tube to be punched. The die core 44 is fixedly connected to the pull rod 21, and the position of the die core 44 inside the square tube 8 is determined by the pull rod 21. A positioning punch inner die 46 is fixed on the upper surface of the die core 44 and directly below the positioning punch. The positioning punch and the positioning punch inner die 46 cooperate together to determine the position of the die core 44. An inner die 45 for the punch is fixed on the upper surface of the die core 44 and directly below the through hole punch and the blind hole punch. The inner die 45 for the punch is provided with a sharp edge. The square tube wall is subjected to the shearing force and extrusion force at the edge of the punch and the inner die 45 for the punch, completing the punching operation.

[0087] As Figure 4 、 Figure 6 and Figure 7 shown, the die blank 10 is provided with a groove along the length direction of the square tube. The part of the square tube 8 to be punched is arranged in the groove. In this embodiment, since the punching of two square tubes is realized simultaneously, two grooves are provided inside the die blank, and the two square tubes 8 are respectively arranged in the two grooves.

[0088] In order to realize the clamping and fixing of the square tube in the groove, two locking blocks 11 are provided in each groove, and the square tube 8 is located between the two locking blocks 11. An arc-shaped groove is provided on the side wall of the locking block 11 facing the groove, and correspondingly, an arc-shaped groove is provided on the inner wall of the die blank. The arc-shaped groove of the locking block and the arc-shaped groove on the inner wall of the die blank form a cylindrical groove, and an interference fit is formed between the locking block 11 and the cylindrical groove. When the workpiece locking column 18 is inserted into the cylindrical groove, the locking block 11 is pushed towards the square tube 8, thereby clamping the square tube 8 between the two locking blocks 11.

[0089] In this embodiment, the clamping of one square tube is realized through two workpiece locking columns 18. Therefore, two arc-shaped grooves are provided at intervals on the side wall of the locking block 11 facing the groove, and correspondingly, two arc-shaped grooves are provided inside the die blank. Since this embodiment can punch two square tubes simultaneously, a total of four workpiece locking columns 18 are included in this die.

[0090] In order to further improve the clamping and fixing effect of the square tube, adjusting set screws 15 are respectively provided at two symmetric side walls of the die blank. The inner end of the adjusting set screw 15 is in threaded connection with the locking block 11, and the adjusting set screw 15 is movably connected with the die blank, that is, internal threads are tapped in the locking block 11, and the set screw through hole in the die blank is a clearance hole. A second spring 41 is connected between the outer end of the adjusting set screw 15 and the die blank, and the second spring 41 is wound around the annular outer side of the adjusting set screw.

[0091] When the square tube needs to be clamped, screw the adjusting set screw 15 towards the locking block 11. At this time, through the threaded connection between the adjusting set screw 15 and the locking block 11, the locking block 11 is pushed towards the square tube, thereby realizing the clamping of the two locking blocks on the square tube. At this time, the second spring 41 between the adjusting set screw 15 and the die core 10 is in a compressed state.

[0092] When the punching of the square tube is completed and the position of the square tube needs to be moved, screw the adjusting set screw 15 out in the direction away from the locking block 11. When the inner end of the adjusting set screw 15 is screwed out from the internal threaded hole of the locking block 11, under the elastic force of the second spring 41, the automatic reset of the adjusting set screw 15 is realized.

[0093] At the bottom surface of the die core directly below the through-hole punching needle, there is a punching and blanking bottom die 43. The punching and blanking bottom die 43 is provided with a blanking through-hole. The blanking through-hole is a tapered groove hole, smaller at the top and larger at the bottom, preventing blanking blockage and ensuring smoother blanking. During the through-hole punching operation of the square tube, the blanking generated during the punching process falls through the blanking through-hole. At the same time, the long-term punching process will also cause wear of the cutting edge of the blanking through-hole, resulting in unsmooth blanking. At this time, the punching and blanking bottom die 43 can be directly replaced.

[0094] The working principle of this die is described as follows.

[0095] Manually feed and install two square tubes to the automatic feeding and retracting mechanism. Through the PLC control system, the lower surface of the upper clamping jaw 29 presses tightly on the upper surface of the square tube 8, and the upper surface of the lower clamping jaw 28 clamps the upper inner wall of the square tube 8, fixedly clamping one end of the square tube. The motor 24 works. Through the meshing between the gear 23 and the rack 22, the rotation of the gear 23 is converted into the linear motion of the rack 22, and at the same time, the sliding plate 20 is driven to move along the machine tool guide rail 19, and at the same time, the square tube 8 is driven to move towards the punching mechanism and move to an appropriate punching position inside the punching mechanism. The motor 25 stops rotating.

[0096] In this embodiment, the punching sequence on the square tube starts from the left end of the square tube and pushes the material to the left in sequence, thereby completing the punching of the square tube in sequence.

[0097] During the first punching process, the square tube 8 is sleeved on the die core 44. At this time, the positioning punching needle inner die 46 is located inside the square tube 8, and the positioning punching needle inner die 45 is located outside the square tube 8. The positioning punching needle 9 is longer than the blind-hole punching needle and the through-hole punching needle. During the first working stroke, the positioning punching needle 9 first punches and combines with the positioning punching needle inner die 45 on the die core 44. At this time, the positioning punching needle plays a role in positioning and stabilizing the die core 44.

[0098] After the first punching is completed, the square tube 8 is pushed to the left. During the subsequent punching process, the positioning punch 9 passes through the blind hole punched by the blind hole punch and engages with the positioning punch inner die 45 on the die core. At this time, the positioning punch plays a role in stabilizing the square tube and the die core.

[0099] When punching the square tube 8, the external oil cylinder applies a downward pressure on the upper template 3. The upper template 3 drives the top plate 4, the middle plate 5, and the punch fixing plate 6 to move downward. The positioning punch 9 positions the square tube and the die core. At the same time, the workpiece locking column 18 moves downward into the cylindrical groove formed by the locking block 11 and the die blank 10. The workpiece locking column 18 pushes the locking block 11 to move towards the square tube 8 side, tightening the square tube 8 to achieve the purpose of locking the square tube and accurate positioning.

[0100] In this embodiment, the blind hole punch 16 and the through hole punch 30 move downward and enter the punch guide plate 7 to achieve punching of four blind holes and one through hole.

[0101] When punching the through hole, the second cylinder 51 contracts and pulls the through hole punch plug 52. At this time, the first through hole in the through hole punch plug 52 is misaligned with the through hole punch slide groove at the bottom of the plug groove. Under the blocking action of the through hole punch plug 52, it plays a blocking role on the through hole punch 30, so that the through hole punch 30 can only complete the punching action downward to achieve through hole punching.

[0102] When only punching blind holes, the piston rod of the second cylinder 51 extends, so that the first through hole in the through hole punch plug 52 is aligned with the through hole punch slide groove at the bottom of the plug groove. Under the upward thrust of the square tube on the through hole punch, the upper end of the through hole punch moves up from the through hole punch slide groove to the first through hole, achieving the effect that the through hole punch does not participate in punching when punching blind holes.

[0103] When a set of punching is completed, the external oil cylinder lifts the upper template 3. The workpiece locking column 18, the through hole punch, and the blind hole punch move up with the upper template 3. After the workpiece locking column 18 leaves the locking block 11, the motor 24 operates and continues to feed forward. While the sliding plate 20 moves, it drives the square tube to move forward to achieve feeding of the square tube, and sequentially achieve punching of the next few groups of blind holes, completing a punching cycle and punching operation of the entire square tube. After the entire square tube is punched, the upper and lower clamping claws are loosened, and the punched square tube can be removed from this mold.

[0104] The above has introduced in detail the square pipe punching die provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention. The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A square tube punching die, characterized in that: It includes an automatic feeding and withdrawing mechanism and a punching mechanism, one end of the square tube is fixedly connected to the automatic feeding and withdrawing mechanism, and the other end of the square tube is arranged in the punching mechanism; The punching mechanism includes a through-hole punch and a blind-hole punch. The blind-hole punch is fixed on a punch fixing plate, and the punch fixing plate is fixedly connected to the upper template. The middle plate is fixedly connected to the upper template, a blocking plate groove is provided in the middle plate, a through-hole punching needle blocking plate can be slidably arranged in the blocking plate groove, a first through hole is provided in the through-hole punching needle blocking plate, a through-hole punching needle sliding groove is correspondingly provided in the middle plate below the blocking plate groove, the upper part of the through-hole punching needle can be movably arranged in the through-hole punching needle sliding groove, and a clearance fit is formed between the through-hole punching needle and the first through hole; When the first through hole and the through hole punching needle slide groove are in a misaligned state, the through hole punching needle completes the punching of the through hole. When the first through hole and the through hole punching needle slide groove are connected up and down, the through hole punching needle enters the first through hole.

2. The square tube punching die according to claim 1, characterized in that: Automatic feeding and withdrawing mechanism includes: A first cylinder, a cylinder body of which is connected to the moving part; A movable plate is fixedly connected to the telescopic rod of the first cylinder, and a groove is provided on a side of the movable plate facing the punching mechanism; A crank, the upper end of which is connected to the end of the telescopic rod of the first cylinder, the lower end of which is fixed with an upper pressing claw, the lower end of which is arranged in the groove and is rotatably connected to the groove wall; The upper pressing claw is located above the square tube; The lower pressing claw is fixedly connected to the movable plate and is located below the inner side surface of the upper wall of the square tube.

3. The square tube punching die according to claim 2, characterized in that: The mobile part includes: The movable bracket comprises a cylinder fixing plate and slide plates located on two symmetrical sides of the cylinder fixing plate, wherein the cylinder fixing plate is fixedly connected to the slide plates on both sides; The gear meshes with the rack, and the rack is fixed on the slide on one side; The machine tool guide rail is located below the slide, and the machine tool guide rail and the slide are slidably connected.

4. The square tube punching die according to claim 1, characterized in that: The punching mechanism comprises: The upper template has a top plate, a middle plate, and a punch pin fixing plate fixedly connected in sequence on its lower surface, a plurality of workpiece locking columns are fixed on the top plate, and a blank punch pin and a positioning punch pin are fixed on the punch pin fixing plate; The lower template has a mold base and a punch guide plate fixedly connected to its upper surface in sequence from bottom to top, the square tube is arranged in the mold base, and the through-hole punch, the non-through-hole punch and the workpiece locking column penetrate the punch guide plate; The ball guide sleeve guide column has a bottom end fixedly connected to the lower template and an upper end movably connected to the upper template.

5. The square tube punching die according to claim 4, characterized in that: Linear Bushings include: The guide column has a bottom end fixedly connected to the lower template, an upper template limiting plate fixed to the top end, and a ball guide sleeve slidably sleeved on the upper end thereof, wherein a plurality of rolling balls are arranged in the ball guide sleeve; The outer steel sleeve is fixed in the upper template and is located outside the annular shape of the ball guide sleeve. There is sliding friction between the outer steel sleeve and the balls of the ball guide sleeve. When the outer steel sleeve moves downward, the ball guide sleeve is driven to move downward by rolling friction. The first spring is wound around the annular outer side of the guide column, one end of the first spring is in contact with the ball guide sleeve, and the other end of the first spring is in contact with the lower template.

6. The square tube punching die according to claim 1, characterized in that: A blocking plate groove is arranged in the middle plate and perpendicular to the length direction of the square tube, and one end of the through-hole punching needle blocking plate is connected to the second cylinder.

7. The square tube punching die according to claim 4, characterized in that: A groove is provided in the mold along the length direction of the square tube, and the part of the square tube to be punched is arranged in the groove; Two locking blocks are provided in each groove, and the square tube is located between the two locking blocks; An arc groove is provided at the side wall of the locking block facing the groove, and a corresponding arc groove is provided at the inner wall of the mold. The arc groove of the locking block and the arc groove of the inner wall of the mold form a cylindrical groove, and the locking block and the cylindrical groove are interference fit.

8. The square tube punching die according to claim 4, characterized in that: Adjusting top screws are respectively arranged at the two symmetrical side walls of the mold, threaded holes are arranged in the corresponding locking blocks, and a light hole is arranged in the mold, the inner end of the adjusting top screw is threadedly connected to the locking block, and the adjusting top bottom is movably connected to the fetal membrane; A second spring is connected between the outer end of the adjusting top screw and the mold tire, and the second spring is wound around the annular outer side of the adjusting top screw.

9. The square tube punching die according to claim 4, characterized in that: A punching and blanking bottom die is arranged on the bottom surface of the mold base just below the through-hole punch needle, and a blanking through hole is arranged on the punching and blanking bottom die. The blanking through hole is a tapered slot hole, which is small at the top and large at the bottom.

Images