Pipe punching die with improved structure

Abstract

The invention discloses a pipe punching die with improved structure, comprising an upper die, a lower die, a punch, a core rod and a core rod positioning device, the upper die can move up and down and is located just above the lower die, the punch is fixedly installed on the upper die, the core rod positioning device is installed on the lower die, and the core rod positioning device can fix and position the core rod on the lower die, the pipe to be punched can be sleeved on the outer side of the circumference of the core rod, the core rod is provided with a die hole and a feed hole, the punch can be inserted into the die hole of the core rod, the side wall of the punch and the side wall of the die hole of the core rod form a butting edge, the upper end of the feed hole and the lower end of the die hole are directly connected to form a radial hollow structure penetrating the core rod, and a guiding inclined surface inclined toward the other side wall of the feed hole is formed on one side wall of the feed hole. The invention improves the smoothness of material discharge, increases the side wall thickness of the feed hole of the core rod, and increases the strength of the core rod. After long-term use, the core rod is not easy to deform and crack, thereby extending the service life of the core rod.

Description

Technical Field

[0001] The invention relates to a hardware mould, in particular to a pipe punching mould with improved structure. Background Art

[0002] At present, there are two ways to process the side wall holes of pipe parts: one is to position the pipe and then perform the hole processing by drilling; the other is to use a punching die for processing, where the pipe is put on a mandrel, the mandrel is fixed on a lower die, a vertical hole is set on the mandrel from top to bottom, and the pipe is punched by a punch on the upper die, and the waste material falls out flatly from the vertical hole of the mandrel. For large-sized punching, the vertical hole size C on the mandrel is very large, and the mandrel is very thin at the side wall of the vertical hole. Long-term punching can easily cause deformation, cracks or even breakage of the mandrel, and the waste material is easily stuck in the vertical hole and difficult to fall out, causing a lot of trouble for pipe punching. Summary of the invention

[0003] In order to overcome the above defects, the present invention provides a pipe punching die with an improved structure, which greatly improves the core rod strength, prolongs the service life of the core rod, improves the pipe punching accuracy, and can realize the smooth discharge of waste.

[0004] The technical solution adopted by the present invention to solve its technical problems is: a structurally improved pipe punching die, comprising an upper die, a lower die, a punch, a core rod and a core rod positioning device, the upper die can be lifted and lowered and is located directly above the lower die, the punch is fixedly installed on the upper die, the core rod positioning device is installed on the lower die, the core rod positioning device can fix the core rod on the lower die, the pipe to be punched can be just sleeved on the outer side of the circumference of the core rod, the core rod is provided with a die hole and a feed hole, the punch can be just inserted into the die hole of the core rod, the side wall of the punch and the side wall of the die hole of the core rod form a cutting edge, the upper end of the feed hole and the lower end of the die hole are directly connected to form a radial hollow structure passing through the core rod, and a guide inclined surface inclined toward the other side wall of the feed hole is formed on one side wall of the feed hole.

[0005] As a further improvement of the present invention, the upper end of the feed hole of the core rod is a vertical hole formed by a vertical surface, the size of which is not less than the size of the die hole, and the die hole is located exactly in the vertical hole, and the guide slope is connected to the lower end of one side wall of the vertical hole.

[0006] As a further improvement of the present invention, the guide slope on the side wall of the core rod discharge hole is formed by splicing a first gentle slope and a first steep slope, the angle between the first gentle slope and the vertical direction is greater than the angle between the first steep slope and the vertical direction, and the first steep slope is connected to the bottom of the first gentle slope.

[0007] As a further improvement of the present invention, the vertical surface at the upper end of the other side wall of the core rod unloading hole is arranged corresponding to the vertical surface on the other side wall of the upper end of the core rod unloading hole and the first gentle inclined surface, and an avoidance inclined surface is formed at the lower end of the other side wall of the core rod unloading hole, and the avoidance inclined surface is inclined in the same direction as the guide inclined surface on one side wall of the core rod unloading hole.

[0008] As a further improvement of the present invention, the avoidance slope at the lower end of the other side wall of the core rod feeding hole is formed by splicing a second gentle slope and a second steep slope, the angle between the second gentle slope and the vertical direction is greater than the angle between the second steep slope and the vertical direction, and the second gentle slope is connected to the bottom of the second steep slope.

[0009] As a further improvement of the present invention, a detachable insert is provided on the core rod, and the die hole is located in the insert.

[0010] As a further improvement of the present invention, the core rod positioning device includes an axial positioning retaining wall, a fixed clamping block, a movable clamping block and a clamping force providing device. The axial positioning retaining wall and the fixed clamping block are fixedly installed on the lower mold at intervals along the axial direction of the core rod. The side walls opposite to the movable clamping block and the fixed clamping block are respectively formed with clamping surfaces matching the shape of the core rod. One end of the core rod can be inserted between the clamping surfaces of the movable clamping block and the fixed clamping block. The fixed clamping block and the core rod are also provided with a guiding positioning structure along the circumferential direction. The clamping force providing device provides the movable clamping block with a clamping force to keep one end of the core rod in a clamped state. The end face of one end of the core rod can just tightly abut against the side wall surface of the axial positioning retaining wall, and the end face of one end of the tube on the core rod can just tightly abut against the side wall surface of the fixed clamping block.

[0011] As a further improvement of the present invention, the guiding and positioning structure is a plane group or a key and keyway group correspondingly arranged on the clamping surface of the core rod and the fixed clamping block.

[0012] As a further improvement of the present invention, the core rod positioning device also includes a support block, which is fixedly mounted on the lower mold, and the support block can just support the lower side of the other end of the core rod.

[0013] As a further improvement of the present invention, the lower end of the punch is an inclined surface or a curved surface with varying height.

[0014] The beneficial effects of the present invention are as follows: the present invention arranges an inclined guiding slope on one side wall of the feeding hole of the mandrel, so that the waste material automatically turns in the feeding hole and slides down in an inclined state, thereby improving the smoothness of material discharge and avoiding the waste material from being stuck in the feeding hole. At the same time, since the inclined surface is formed on one side wall of the feeding hole, the width of the feeding hole is greatly reduced, the side wall thickness of the feeding hole of the mandrel is increased, the strength of the mandrel is improved, and the mandrel is not easy to deform and crack after long-term use, thereby extending the service life of the mandrel and reducing the cost of pipe punching processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the main view of the structural principle of the prior art;

[0016] Figure 2 for Figure 1 Enlarged view of part A in the middle;

[0017] Figure 3 It is the main view of the structural principle of the present invention;

[0018] Figure 4 for Figure 3 Enlarged view of middle part B;

[0019] Figure 5 It is a main view of the core rod blanking structure principle of the prior art;

[0020] Figure 6 It is a top view of the core rod blanking structure principle of the prior art;

[0021] Figure 7 This is a main view of the core rod blanking structure principle of the present invention;

[0022] Figure 8 It is a top view of the core rod blanking structure principle of the present invention. DETAILED DESCRIPTION

[0023] Embodiment: A structurally improved pipe punching die comprises an upper die 1, a lower die 2, a punch 3, a core rod 4 and a core rod positioning device, wherein the upper die 1 can be lifted and lowered and is located directly above the lower die 2, the punch 3 is fixedly mounted on the upper die 1, the core rod positioning device is mounted on the lower die 2, the core rod positioning device can fix and position the core rod 4 on the lower die 2, the tube to be punched can be just sleeved on the outer side of the circumference of the core rod 4, the core rod 4 is provided with a die hole 5 and a feed hole 6, the punch 3 can just be inserted into the die hole 5 of the core rod 4, the side wall of the punch 3 and the side wall of the die hole 5 of the core rod 4 form a cutting edge, the upper end of the feed hole 6 and the lower end of the die hole 5 are directly connected to form a radial hollow structure penetrating the core rod 4, and a guide slope inclined toward the other side wall of the feed hole 6 is formed on one side wall of the feed hole 6.

[0024] During production, the tube to be punched is put on the mandrel 4, and then the mandrel 4 is fixed and positioned on the lower die 2 by the mandrel positioning device. The upper die 1 descends and carries the punch 3 to punch the upper side wall of the tube 10 on the mandrel 4 to form a punching hole. The punched waste piece 7 enters the discharge hole 6 from the die hole 5. When the waste piece falls in the discharge hole 6, one side wall contacts the guide inclined surface on the discharge hole 6, and the waste piece begins to tilt and slide along the guide surface. The width dimension D of the upper and lower feeding holes 6 of the mandrel 4 of this structure is greatly reduced, which greatly improves the strength of the mandrel 4. After long-term punching, the mandrel 4 is not prone to deformation or breakage. The waste material tilts and slides down. After the tube is removed from the mandrel 4, the piece can fall out smoothly, avoiding material jamming.

[0025] The upper end of the material discharge hole 6 of the mandrel 4 is a vertical hole formed by a vertical surface, the size of which is not less than the size of the die hole 5, and the die hole 5 is just located in the vertical hole, and the guide slope is connected to the lower end of one side wall of the vertical hole. The upper end of the material discharge hole 6 of the mandrel 4 is formed with a vertical hole that is not less than the die hole 5 and is directly connected with the die hole, so that the waste piece falls smoothly into the material discharge hole 6 in the die hole 5.

[0026] The guide slope on one side wall of the material discharge hole 6 of the mandrel 4 is formed by splicing a first gentle slope 8 and a first steep slope 9, the angle between the first gentle slope 8 and the vertical direction is greater than the angle between the first steep slope 9 and the vertical direction, and the first steep slope 9 is connected to the lower part of the first gentle slope 8. Under the action of the first gentle slope 8, the guide slope of the mandrel 4 rapidly reduces the width of the material discharge hole 6, and the guide slope of the mandrel 4 realizes rapid and smooth discharge of waste under the action of the first steep slope 9. The first vertical surface and the first gentle slope 8, as well as the first gentle slope 8 and the first steep slope 9, are connected by rounded transition, so that one side of the sheet can turn and slide on a smooth surface, and the turning and sliding are smooth to avoid jamming.

[0027] The vertical surface at the upper end of the other side wall of the mandrel 4 material discharge hole 6 corresponds to the vertical surface on the other side wall of the mandrel 4 material discharge hole 6 and the first gentle slope 8, and the lower end of the other side wall of the mandrel 4 material discharge hole 6 is formed with an avoidance slope, and the avoidance slope is inclined in the same direction as the guide slope on one side wall of the mandrel 4 material discharge hole 6. The other side wall of the mandrel 4 material discharge hole 6 is smoothly connected with the die hole 5 by setting a second vertical surface, and the width of the material discharge hole 6 can be quickly reduced corresponding to the first gentle slope 8, and the waste sheet can be prevented from being stuck. The lower end of the other side wall of the mandrel 4 material discharge hole 6 forms an avoidance slope, which corresponds to the first steep slope 9, and can increase the outlet size of the mandrel 4 material discharge hole 6, so as to realize the rapid discharge of the waste sheet.

[0028] The avoidance slope at the lower end of the other side wall of the material discharge hole 6 of the mandrel 4 is formed by splicing a second gentle slope 11 and a second steep slope 12, the angle between the second gentle slope 11 and the vertical direction is greater than the angle between the second steep slope 12 and the vertical direction, and the second gentle slope 11 is connected to the lower part of the second steep slope 12. The two-level avoidance slope makes the width of the discharge port of the material discharge hole 6 gradually increase, which is conducive to the rapid and smooth discharge of waste.

[0029] The mandrel 4 is provided with a removable insert 13, and the die hole 5 is located in the insert 13. An outwardly expanded embedding groove is formed on the side wall of the mandrel 4, which is directly opposite to the blanking hole 6. The insert 13 can be embedded in this outwardly expanded embedding groove. When punching holes of different specifications and sizes, or when the die hole 5 is damaged, only one insert 13 needs to be replaced, and there is no need to replace the entire mandrel 4, which greatly reduces the production cost and improves the versatility of the mandrel 4.

[0030] The core rod positioning device includes an axial positioning retaining wall 14, a fixed clamping block 15, a movable clamping block 16 and a clamping force providing device. The axial positioning retaining wall 14 and the fixed clamping block 15 are fixedly installed on the lower mold 2 at intervals along the axial direction of the core rod 4. The movable clamping block 16 and the fixed clamping block 15 are respectively formed with clamping surfaces matching the shape of the core rod 4 on the side walls opposite to the fixed clamping block 15. One end of the core rod 4 can be inserted between the clamping surfaces of the movable clamping block 16 and the fixed clamping block 15. The fixed clamping block 15 and the core rod 4 are also provided with a guiding positioning structure along the circumferential direction. The clamping force providing device provides the movable clamping block 16 with a clamping force to keep one end of the core rod 4 in a clamped state. The end face of one end of the core rod 4 can just press against the side wall surface of the axial positioning retaining wall 14, and the end face of one end of the tube on the core rod 4 can just press against the side wall surface of the fixed clamping block 15. When the mandrel 4 is positioned, one end of the mandrel 4 presses against the axial positioning retaining wall 14 to realize the axial positioning of the mandrel 4. At the same time, the movable clamping block 16 and the fixed clamping block 15 cooperate to clamp one end of the mandrel 4 in position, and at the same time, the side wall of the fixed clamping block 15 axially limits one end of the tube sleeved on the mandrel 4. The fixed clamping block 15 and the mandrel 4 realize the circumferential positioning of the mandrel 4 through the guiding positioning structure, so that its die hole 5 is in a facing state with the punch 3 on the upper die 1. The movable clamping block 16 and the fixed clamping block 15 can be hinged on one side and connected, and then the other side of the two can be connected through a connecting piece to realize the clamping of the mandrel 4. The movable clamping block 16 can also be raised and lowered It is installed just above the fixed clamping block 15, and the movable clamping block 16 and the fixed clamping block 15 are clamped together by a pressing device. The pressing device can be a cylinder, a quick clamp, etc. These are all equivalent replacement structures that can be easily thought of by technicians in this field based on this patent, and they belong to the protection scope of this patent. In addition to the structure that the fixed clamping block 15 and the movable clamping block 16 are used to clamp together, the mandrel positioning device can also position the mandrel 4 by clamping one end of the mandrel 4 with a chuck and fixing it with connectors such as pins and bolts. These are also all equivalent replacement structures that can be easily thought of by technicians in this field based on this patent, and they belong to the protection scope of this patent.

[0031] The guide positioning structure is a plane group 17 or a key and keyway group correspondingly arranged on the clamping surface of the core rod 4 and the fixed clamping block 15. A plane is formed on the circumferential outer wall of one end of the core rod 4 by milling, and a plane matching it is also formed on the clamping surface of the fixed clamping block 15. The positioning in the circumferential direction is achieved by the contact between the planes. Alternatively, a keyway may be provided on one of the clamping surfaces of the core rod 4 or the fixed clamping block 15, and a key may be provided on the other, and the positioning in the circumferential direction of the core rod 4 may be achieved by the cooperation between the keyway and the key. In addition, an axially extending slide groove may be provided on the clamping surface of the fixed clamping block 15, and a pin may be provided on the core rod 4. The pin may be used to limit the position of the core rod 4 in the circumferential direction in the slide groove, so as to ensure that the die hole 5 on the core rod 4 is directly opposite to the punch 3.

[0032] The mandrel positioning device also includes a support block 18, which is fixedly mounted on the lower die 2, and the support block 18 can just support the lower side of the other end of the mandrel 4. The support block 18 cooperates with the clamping block group to support and position both ends of the mandrel 4, prevent the mandrel 4 from hanging in the air, and improve the strength of the mandrel 4 and the punching accuracy.

[0033] The lower end of the punch 3 is an inclined surface or a curved surface with a varying height. The lower end of the punch 3 is provided with an inclined surface or a curved surface with a varying height so that the lower end of the punch 3 does not contact different positions of the tube surface at the same time, so that cutting with a small blanking force can be achieved, and the core rod 4 is prevented from being damaged by a large impact force, and can also be adapted to blanking of the stepped portion of a tube with a step.

Claims

1. A pipe punching die with improved structure, characterized in that: The invention comprises an upper die (1), a lower die (2), a punch (3), a core rod (4) and a core rod positioning device, wherein the upper die can be lifted and lowered and is located directly above the lower die, the punch is fixedly mounted on the upper die, the core rod positioning device is mounted on the lower die, the core rod positioning device can fix the core rod on the lower die, a tube to be punched can be sleeved on the outer side of the circumference of the core rod, a die hole (5) and a feed hole (6) are provided on the core rod, the punch can be inserted into the die hole of the core rod, a side wall of the punch and a side wall of the die hole of the core rod form a butting edge, an upper end of the feed hole and a lower end of the die hole are butted together to form a radial hollow structure penetrating the core rod, and the feed hole is A guiding inclined surface is formed on the side wall and is inclined toward the other side wall of the blanking hole. The upper end of the blanking hole of the mandrel is a vertical hole formed by a vertical surface, the size of which is not less than the size of the die hole, and the die hole is just located in the vertical hole. The guiding inclined surface is connected to the lower end of one side wall of the vertical hole. The guiding inclined surface on one side wall of the blanking hole of the mandrel is formed by splicing a first gentle inclined surface (8) and a first steep inclined surface (9). The angle between the first gentle inclined surface and the vertical direction is greater than the angle between the first steep inclined surface and the vertical direction, and the first steep inclined surface is connected below the first gentle inclined surface. The vertical surface at the upper end of the other side wall of the blanking hole of the mandrel is connected to the other side wall of the blanking hole of the mandrel. The vertical surface on one side wall and the first gentle inclined surface are arranged correspondingly, and an avoidance inclined surface is formed at the lower end of the other side wall of the mandrel unloading hole. The avoidance inclined surface and the guide inclined surface on the one side wall of the mandrel unloading hole are inclined in the same direction. The avoidance inclined surface at the lower end of the other side wall of the mandrel unloading hole is formed by splicing a second gentle inclined surface (11) and a second steep inclined surface (12). The angle between the second gentle inclined surface and the vertical direction is greater than the angle between the second steep inclined surface and the vertical direction, and the second gentle inclined surface is connected to the lower part of the second steep inclined surface. The mandrel positioning device comprises an axial positioning retaining wall (14), a fixed clamping block (15), a movable clamping block (16) and a clamping A tightening force providing device, wherein the axial positioning retaining wall and the fixed clamping block are fixedly installed on the lower mold at intervals along the axial direction of the core rod, and clamping surfaces matching the shape of the core rod are respectively formed on the side walls opposite to the movable clamping block and the fixed clamping block, and one end of the core rod can be inserted between the clamping surfaces of the movable clamping block and the fixed clamping block, and the fixed clamping block and the core rod are also provided with a guiding positioning structure along the circumferential direction, and the clamping force providing device provides the movable clamping block with a clamping force to keep one end of the core rod in a clamped state, and the end face of one end of the core rod can just tightly abut against the side wall surface of the axial positioning retaining wall, and the end face of one end of the tube on the core rod can just tightly abut against the side wall surface of the fixed clamping block.

2. The pipe punching die with improved structure according to claim 1, characterized in that: The core rod is provided with a detachable insert (13), and the die hole is located in the insert.

3. The pipe punching die with improved structure according to claim 1, characterized in that: The guiding and positioning structure is a plane group (17) or a key and keyway group correspondingly arranged on the clamping surfaces of the core rod and the fixed clamping block.

4. The pipe punching die with improved structure according to claim 3 is characterized in that: The core rod positioning device also includes a support block (18), which is fixedly mounted on the lower die and can just support the lower side of the other end of the core rod.

5. The pipe punching die with improved structure according to claim 1, characterized in that: The lower end of the punch is an inclined surface or a curved surface with varying height.

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