Punch forming die for self-plugging rivet

Abstract

The utility model discloses a punch forming die for a self-plugging rivet, which comprises an upper die frame (1), a lower die frame (2) and a clamp (3), a positioning seat (4) is slidably connected in the lower die frame (2), a forming cavity (5) is arranged in the positioning seat (4), a first elastic piece (6) is connected between the positioning seat (4) and the lower die frame (2), and a punching rod (7) fixedly connected with the lower die frame (2) is arranged in the forming cavity (5). A discharging pipe (8) is arranged outside the punching rod (7), and the punching rod (7), the discharging pipe (8) and the positioning seat (4) are nested inside and outside and are coaxially arranged; a material ejecting pipe (9) is connected into the upper die frame (1) in a sliding mode, and the end, away from the lower die frame (2), of the material ejecting pipe (9) is connected with a first driving rod (10). According to the utility model, the machining precision and stability of the rivet body blank can be improved.

Description

Technical Field

[0001] The utility model relates to a stamping die, in particular to a stamping forming die for blind rivets. Background Art

[0002] In the process of punching blind rivets, it is necessary to punch holes in the rivet body blank through a stamping die, that is, to cut off the excess material between the blind holes at both ends of the rivet body blank and form a through hole in the middle of the rivet body blank. The existing method of punching the rivet body blank is to first transport the rivet body blank to the stamping station through a clamp, and then the punching rod pushes the rivet body blank after ejection, so that the rivet body blank is separated from the clamp after being pushed and then buckled into the mold cavity at the rear. The mold cavity limits the rivet body blank axially after it is buckled into place, and at the same time, the punching rod continues to push and completes the cutting action of the inner hole of the rivet body blank. After the stamping is completed, the punching rod is reset and the discharge rod in the mold cavity pushes the rivet body blank back into the clamp to complete the cutting action.

[0003] However, the defect of the above-mentioned stamping method is that a slender hollow tube structure will be formed at one end of the rivet body blank during stamping, and when the mold cavity is buckled and limited on the rivet body blank, the hollow tube will extend to the outside of the mold cavity and remain in the air, and the punching rod will complete the cutting action after passing through the hollow tube; and this will cause the punching rod to easily cause the hollow tube to tilt or deform under force during the stamping process, thereby affecting the structural stability of the rivet body blank and the concentricity of the inner hole after forming.

[0004] Therefore, the existing punching die punching method for the inner hole of the rivet body blank has the problems of low processing accuracy and easy damage to the rivet body blank. Utility Model Content

[0005] The utility model aims to provide a punching and forming die for blind rivets, which can improve the processing accuracy and stability of rivet body blanks.

[0006] The technical solution of the utility model is as follows: a stamping forming die for a blind rivet, comprising an upper die frame, a lower die frame and a clamp, a positioning seat is slidably connected in the lower die frame, a forming cavity is arranged in the positioning seat, a first elastic member is connected between the positioning seat and the lower die frame, a punching rod fixedly connected to the lower die frame is arranged in the forming cavity, a discharge pipe is arranged outside the punching rod, the punching rod, the discharge pipe and the positioning seat are nested inside and outside and coaxially arranged; a ejecting pipe is slidably connected in the upper die frame, and a first driving rod is connected to the ejecting pipe at one end away from the lower die frame;

[0007] The clamp is used to form a circular hole for sliding connection with the rivet body blank after clamping, and to form an opening for the ejector pipe to pass through after opening;

[0008] The ejector tube is used to eject the rivet body blank, so that the rivet body blank in the fixture enters the forming cavity under the ejector action;

[0009] The forming cavity is used to limit the radial position of the rivet body blank when it is moving, and to limit the axial position of the rivet body blank after it is fully fastened;

[0010] The punching rod is used to shear the excess material in the middle of the rivet body blank, so that a through hole is formed in the middle of the rivet body blank after shearing.

[0011] In the aforementioned stamping die for blind rivets, a limiting surface for axially limiting the positioning seat is provided in the lower die frame.

[0012] In the aforementioned stamping forming die for blind rivets, the end of the discharge pipe is connected to a push plate, the outer side of the push plate is connected to a second driving rod, and the end of the second driving rod extends to the outer side of the lower die frame.

[0013] In the aforementioned stamping forming die for blind rivets, a positioning rod slidably connected to a push plate is provided at the end of the second driving rod, one end of the positioning rod passes through the push plate and is connected to a cover plate, and a second elastic member is connected between the second driving rod and the push plate;

[0014] The discharge pipe is used to extrude and limit the rivet body blank under the drive of the second drive rod;

[0015] The second elastic member is used to apply an axial extrusion force to the rivet body blank when the discharge pipe contacts the rivet body blank, and prevent the discharge pipe and the ejection pipe from being crushed due to asynchronous movement.

[0016] In the aforementioned stamping and forming die for blind rivets, a blanking port for discharging excess material is provided on the side wall of the ejector tube.

[0017] Compared with the prior art, the utility model has the following characteristics:

[0018] (1) The utility model can push the rivet body blank into the forming cavity by the push tube before the clamp is opened, and use the push tube and the forming cavity to limit the rivet body blank from both ends, so that the rivet body blank can maintain a coaxial state with the positioning seat during the movement; under the limiting effect, the clamp can form an opening for the push tube to pass through after opening, and the push tube can completely push the rivet body blank into the forming cavity after passing through the clamp; after the rivet body blank enters the forming cavity, the punch rod can impact the inner hole of the rivet body blank to achieve the cutting action, and the rivet body blank can be limited by the forming cavity during the cutting process, so as to avoid the deformation of the rivet body blank caused by the impact, thereby improving the processing accuracy and stability of the utility model;

[0019] (2) After the rivet blank is cut, the rivet blank can be pushed out of the forming cavity through the discharge pipe, and the ejector pipe is used to make the rivet blank coaxial with the circular hole of the clamp after ejection; when the rivet blank returns to its original position, the clamp can be closed again and resume clamping the rivet blank, thereby realizing its limiting and conveying functions; on this basis, by limiting the connection structure of the second driving rod and the push plate, the discharge pipe can, during the ejection process, drive the second elastic member to contract and maintain the compression of the rivet blank to avoid radial deviation of the rivet blank; on the other hand, the push plate can also form a suspended state along the axial direction during the ejection process, thereby effectively preventing the discharge pipe and the ejector pipe from loosening or over-extruding the rivet blank due to asynchronous movements, thereby ensuring the ejection stability of the rivet blank;

[0020] (3) On the basis of the above structure, when the rivet body blank cannot be directly pressed into the molding cavity due to its short length, the manufacturer can limit and convey the rivet body blank from both ends by extending the discharge pipe into the discharge and ejection pipe, so that the rivet body blank can still stably enter the molding cavity after the clamp is opened, thereby improving the applicability of the utility model;

[0021] Therefore, the utility model can improve the processing accuracy and stability of the rivet body blank. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of the structure of the rivet body blank when entering the forming cavity in Example 1;

[0023] Figure 2 is a schematic diagram of the structure of the rivet body blank after stamping in Example 1;

[0024] Figure 3 is a schematic structural diagram of the rivet body blank when entering the forming cavity in Example 2;

[0025] Figure 4 yes Figure 3 A-direction enlarged view;

[0026] Figure 5 is a schematic diagram of the structure of the rivet body blank after stamping in Example 2;

[0027] Figure 6 It is a stamping schematic diagram of the existing rivet body blank.

[0028] The marks in the accompanying drawings are: 1-upper mold frame, 2-lower mold frame, 3-clamp, 4-positioning seat, 5-molding cavity, 6-first elastic part, 7-punching rod, 8-discharging pipe, 9-pushing pipe, 10-first driving rod, 11-limiting surface, 12-push plate, 13-second driving rod, 14-cover plate, 15-second elastic part, 16-dropping port, 131-positioning rod. DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0030] Embodiment 1. A stamping die for blind rivets, comprising: Figure 1-2 As shown, it includes a split upper mold frame 1, a lower mold frame 2 and a clamp 3, a positioning seat 4 is slidably connected in the lower mold frame 2, a molding cavity 5 is arranged in the positioning seat 4, a first elastic member 6 is connected between the positioning seat 4 and the lower mold frame 2, a punching rod 7 fixedly connected to the lower mold frame 2 is arranged in the molding cavity 5, a discharge pipe 8 is arranged outside the punching rod 7, and the punching rod 7, the discharge pipe 8 and the positioning seat 4 are nested inside and outside and coaxially arranged; a ejecting pipe 9 is slidably connected in the upper mold frame 1, and a first driving rod 10 is connected to the ejecting pipe 9 at one end away from the lower mold frame 2;

[0031] The clamp 3 is used to form a circular hole for sliding connection with the rivet body blank after clamping, and to form an opening for the ejector tube 9 to pass through after opening;

[0032] The ejector tube 9 is used to push the rivet body blank, so that the rivet body blank in the fixture 3 enters the forming cavity 5 under the pushing action;

[0033] The forming cavity 5 is used to limit the radial position of the rivet body blank when it is moving, and to limit the axial position of the rivet body blank after it is fully fastened;

[0034] The punching rod 7 is used to shear the excess material in the middle of the rivet body blank, so that a through hole is formed in the middle of the rivet body blank after shearing.

[0035] The lower mold frame 2 is provided with a limiting surface 11 for axially limiting the positioning seat 4 .

[0036] The end of the discharge pipe 8 is connected to a push plate 12 , and the push plate 12 and the discharge pipe 8 are fixedly connected. The outer side of the push plate 12 is connected to a second driving rod 13 , and the end of the second driving rod 13 extends to the outer side of the lower mold frame 2 .

[0037] The side wall of the ejector tube 9 is provided with a discharge port 16 for discharging the residual material.

[0038] When the rivet blank is punched, the clamp first transports the rivet blank to between the upper die frame 1 and the lower die frame 2, and the rivet blank, the ejector tube 9 and the forming cavity 5 are coaxially arranged. Then the first driving rod 10 drives the ejector tube 9 to push forward, so that the rivet blank enters the forming cavity 5 after being pushed. After the rivet blank enters the forming cavity 5, the forming cavity 5 can limit the rivet blank so that the rivet blank maintains a coaxial position during the movement; then the clamp 3 is opened and the ejector tube 9 passes through the clamp 3 to continue to push the rivet blank, so that the rivet blank is completely buckled into the forming cavity 5 under the pushing action.

[0039] When the rivet body blank is completely buckled in, the punching rod 7 extends into the blind hole at one end of the rivet body blank, and then the ejector tube 9 continues to push the rivet body blank and drive the positioning seat 4 to shrink inward. At the same time, the punching rod 7 cuts off the excess material at the inner hole of the rivet body blank as the positioning seat 4 shrinks, and then pushes the excess material into the inner hole of the ejector tube 9, so that the excess material is discharged from the blanking port 16 under the pushing action.

[0040] After the punching action is completed, the ejector tube 9 returns to its original position, and then the second elastic member 15 drives the discharge tube 8 to push out and push the rivet body blank, so that the rivet body blank returns to the clamping position under the pushing action. When the rivet body blank reaches the clamping position, the end of the rivet body blank is still located in the forming cavity 5. At this time, the clamp 3 closes and clamps the rivet body blank, and the discharge tube 8 continues to push and completely pushes the rivet body blank out of the forming cavity. In this way, the clamp 3 can transport the rivet body blank to the next station, completing a punching process of the rivet body blank.

[0041] Embodiment 2. A stamping die for blind rivets, comprising: Figure 3-5 As shown, it includes a split upper mold frame 1, a lower mold frame 2 and a clamp 3, a positioning seat 4 is slidably connected in the lower mold frame 2, a molding cavity 5 is arranged in the positioning seat 4, a first elastic member 6 is connected between the positioning seat 4 and the lower mold frame 2, a punching rod 7 fixedly connected to the lower mold frame 2 is arranged in the molding cavity 5, a discharge pipe 8 is arranged outside the punching rod 7, and the punching rod 7, the discharge pipe 8 and the positioning seat 4 are nested inside and outside and coaxially arranged; a ejecting pipe 9 is slidably connected in the upper mold frame 1, and a first driving rod 10 is connected to the ejecting pipe 9 at one end away from the lower mold frame 2;

[0042] The clamp 3 is used to form a circular hole for sliding connection with the rivet body blank after clamping, and to form an opening for the ejector tube 9 to pass through after opening;

[0043] The ejector tube 9 is used to push the rivet body blank, so that the rivet body blank in the fixture 3 enters the forming cavity 5 under the pushing action;

[0044] The forming cavity 5 is used to limit the radial position of the rivet body blank when it is moving, and to limit the axial position of the rivet body blank after it is fully fastened;

[0045] The punching rod 7 is used to shear the excess material in the middle of the rivet body blank, so that a through hole is formed in the middle of the rivet body blank after shearing.

[0046] The lower mold frame 2 is provided with a limiting surface 11 for axially limiting the positioning seat 4 .

[0047] The end of the discharge pipe 8 is connected to a push plate 12 , and the push plate 12 and the discharge pipe 8 are fixedly connected. The outer side of the push plate 12 is connected to a second driving rod 13 , and the end of the second driving rod 13 extends to the outer side of the lower mold frame 2 .

[0048] The end of the second driving rod 13 is provided with a positioning rod 131 slidably connected to the push plate 12, one end of the positioning rod 131 passes through the push plate 12 and is threadedly connected to the cover plate 14, and a second elastic member 15 sleeved on the outside of the positioning rod 131 is connected between the second driving rod 13 and the push plate 12;

[0049] The discharge pipe 8 is used to squeeze and limit the rivet body blank when entering or leaving the forming cavity 5 under the drive of the second driving rod 13;

[0050] The second elastic member 15 is used to apply an axial extrusion force to the rivet body blank when the discharge pipe 8 contacts the rivet body blank, and prevent the discharge pipe 8 and the ejection pipe 9 from being crushed due to asynchronous movement.

[0051] The side wall of the ejector tube 9 is provided with a discharge port 16 for discharging the residual material.

[0052] Compared with the first embodiment, the present embodiment further defines the connection structure between the push plate 12 and the second driving rod 13, so that when the rivet body blank is fed, it can be pushed out by the discharge pipe 8 and replace the molding cavity 5 to limit the end of the rivet body blank, so that the rivet body blank can be smoothly buckled into the molding cavity 5 under the limiting effect; when the rivet body blank is discharged, the discharge pipe 8 cooperates with the ejection pipe 9 to clamp and transport the rivet body blank from both ends after being ejected, so that the rivet body blank can still maintain a coaxial position when it leaves the molding cavity 5, thereby ensuring its discharge stability. During the clamping process, the discharge pipe 8 and the ejection pipe 9 can, on the one hand, clamp the rivet body blank through the cooperation of the positioning rod 131 and the second elastic member 15 to avoid the deviation of the rivet body blank; on the other hand, it can also reduce the requirements for the synchronization of the discharge pipe 8 and the ejection pipe 9, so as to avoid the problem of the rivet body blank being crushed or falling due to synchronization problems. With the above cooperation, the present embodiment can punch rivet body blanks with relatively short lengths, thereby improving the practicability of the present utility model.

Claims

1. A stamping die for blind rivets, characterized in that: The mold comprises an upper mold frame (1), a lower mold frame (2) and a clamp (3); a positioning seat (4) is slidably connected inside the lower mold frame (2); a molding cavity (5) is provided inside the positioning seat (4); a first elastic member (6) is connected between the positioning seat (4) and the lower mold frame (2); a punching rod (7) fixedly connected to the lower mold frame (2) is provided inside the molding cavity (5); a discharge pipe (8) is provided outside the punching rod (7); the punching rod (7), the discharge pipe (8) and the positioning seat (4) are nested inside and outside and are coaxially arranged; a ejecting pipe (9) is slidably connected inside the upper mold frame (1); and a first driving rod (10) is connected to the ejecting pipe (9) at one end away from the lower mold frame (2); The clamp (3) is used to form a circular hole for sliding connection with the rivet body blank after clamping, and to form an opening for the ejector tube (9) to pass through after opening; The ejector tube (9) is used to eject the rivet body blank, so that the rivet body blank in the fixture (3) enters the molding cavity (5) under the ejector action; The forming cavity (5) is used to limit the radial position of the rivet body blank when it is moving, and to limit the axial position of the rivet body blank after the rivet body blank is completely fastened; The punching rod (7) is used to shear the excess material in the middle of the rivet body blank, so that a through hole is formed in the middle of the rivet body blank after shearing.

2. A stamping die for blind rivets according to claim 1, characterized in that: The lower mold frame (2) is provided with a limiting surface (11) for axially limiting the positioning seat (4).

3. The punching die for blind rivets according to claim 1, characterized in that: The end of the discharge pipe (8) is connected to a push plate (12), the outer side of the push plate (12) is connected to a second driving rod (13), and the end of the second driving rod (13) extends to the outer side of the lower mold frame (2).

4. A stamping die for blind rivets according to claim 3, characterized in that: A positioning rod (131) slidably connected to the push plate (12) is provided at the end of the second driving rod (13); one end of the positioning rod (131) passes through the push plate (12) and is connected to the cover plate (14); a second elastic member (15) is connected between the second driving rod (13) and the push plate (12); The discharge pipe (8) is used to extrude and limit the rivet body blank under the drive of the second drive rod (13); The second elastic member (15) is used to apply an axial extrusion force to the rivet body blank when the discharge pipe (8) contacts the rivet body blank, and to prevent the rivet body blank from being crushed due to asynchronous movement of the discharge pipe (8) and the ejection pipe (9).

5. The punching die for blind rivets according to claim 1, characterized in that: A material discharge port (16) for discharging excess material is provided on the side wall of the ejecting pipe (9).

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