CN112676435B

CN112676435B - Manual blanking equipment and method

Info

Publication number: CN112676435B
Application number: CN202110129903.XA
Authority: CN
Inventors: 樊曙天; 王小康; 徐兴超; 王佳琪; 范一凡
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2022-10-28
Anticipated expiration: 2041-01-29
Also published as: CN112676435A

Abstract

The invention provides manual blanking equipment and a manual blanking method. Through the effect of the prepressing die, the generation starting point of cracks is changed, so that the possibility of burr generation is reduced, the section quality of the blanking part is improved, the subsequent deburring process is avoided, the production efficiency is improved, and the production cost is reduced.

Description

Manual blanking equipment and method

Technical Field

The invention relates to the technical field of stamping equipment, in particular to manual blanking equipment and a manual blanking method.

Background

Manual presses in machinery are devices that apply pressure to a material to plastically deform it to obtain the desired shape and precision. Through changing different moulds, the manual punching machine can complete operations such as blanking, punching, forming, pulling, trimming, fine punching, shaping, riveting, extruding and the like on the plate. During the blanking process, plastic deformation and crack propagation are the main causes of the burr generation: during blanking, along with the increasing of the pressure applied to the sheet by the male die, extremely tiny fracture cracks are generated in the metal materials in the side areas of the cutting edges of the female die and the male die in sequence, then the cracks are expanded continuously, and finally confluence is generated, so that the metal sheet is fractured and separated; however, since the starting point of the crack generation is not at the die cutting edge, but at the side surface of the cutting edge slightly away from the cutting edge, when the crack penetrates, excess metal with different heights and thicknesses remains on the edge of the surface of the blanking member, and burrs are formed.

In order to solve the problem of burrs in the current industrial production, a method of deburring after blanking is mainly adopted. However, this method requires further processing, which reduces the production efficiency and increases the production cost.

Disclosure of Invention

The manual blanking equipment comprises a manual punch, a die and a prepressing device, wherein the prepressing device comprises a base, a prepressing die and a prepressing handle, the prepressing die is pressed into a plate by the prepressing handle during working, and then the blanking process is finished by the manual punch. Through the effect of the prepressing die, the generation starting point of cracks is changed, so that the possibility of burr generation is reduced, the section quality of the blanking part is improved, the subsequent deburring process is avoided, the production efficiency is improved, and the production cost is reduced.

The technical scheme adopted by the invention for solving the technical problem is as follows:

a manual blanking device comprises a manual punch and a die, wherein the die is arranged on a bottom plate of the manual punch, and the manual blanking device also comprises a prepressing device, wherein the prepressing device comprises a base, a prepressing die and a prepressing handle; the base is arranged on the die; the pre-pressing die is arranged on the base and provided with a punch passage, the punch passage is coaxial with a punch of the manual punching machine, and the punch can penetrate through the punch passage; the pre-pressing handle is connected with the base and used for enabling the pre-pressing die to move downwards, the tail end of the pre-pressing die pre-cuts the workpiece, and the punch penetrates through the punch channel to punch the workpiece.

In the scheme, a flange is arranged on the outer circumference of the upper end of the prepressing die, a cutting edge is arranged at the tail end of the prepressing die, and a base part is arranged between the flange and the cutting edge; the cutting edge comprises an inner blade surface and an outer blade surface, the inner blade surface is the inner wall of the punch channel, and the tail end of the cutting edge is a tip which is inclined inwards and becomes thinner gradually downwards along the outer blade surface.

In the above scheme, the pre-pressing device further comprises a clamping piece; the clamping piece is provided with a fourth through hole and a T-shaped groove for accommodating the prepress die; the flange and the base of the pre-mold are mounted in the T-shaped groove; the fourth through hole is communicated and coaxial with the punch channel of the pre-pressing die; two sides of the clamping piece are connected with the base in a sliding manner; the bottom plate is provided with a first support, the prepressing handle is rotatably installed on the first support, and the tail end of the prepressing handle is connected with the two sides of the clamping piece.

Furthermore, the clamping piece both sides have the arch, are equipped with the stand on the base of both sides respectively, the stand has the spout, the arch can reciprocate in the spout of stand.

Furthermore, the pre-pressing handle comprises a handle, a pressing rod and a connecting rod, the handle is connected with one end of the pressing rod, and the other end of the pressing rod is connected with the clamping piece through the connecting rod; the first support is rotatably connected with the pressure rod.

In the scheme, the upper ends of the bases on the two sides of the die are connected through a flat plate to form an omega shape, the top of the flat plate is provided with a third through hole, the flange of the prepressing die is positioned above the third through hole, and the base of the prepressing die penetrates through the third through hole; second supports are respectively arranged at the top of the flat plate and positioned at two sides of the third through hole; the pre-compaction handle is two L-shaped rods, the pre-compaction handle is respectively rotatably connected with the second support, one end of the pre-compaction handle is positioned above the pre-compaction die, and the pre-compaction die can be pressed downwards.

In the scheme, the prepressing handle is a rod with an annular structure; a base on one side of the die is provided with a stop block, and a base on the other side of the die is provided with a third support;

one end of the prepressing handle close to the annular structure is rotatably connected with the third support, the annular structure is provided with a through hole, the lower end of the prepressing handle penetrates through the through hole, a flange at the upper end of the prepressing handle is connected with the annular structure, and the other end of the prepressing handle is positioned above the stop block.

In the above scheme, the outer blade face and the inner blade face form an included angle α, and the included angle α is 30-60 °.

A method according to the manual blanking device, comprising the steps of:

s1, placing a plate to be processed on the die;

s2, applying pressure to a pre-pressing die through a pre-pressing handle of the pre-pressing device, and enabling the pre-pressing die to move downwards and press the pre-pressing die into the surface of the plate;

and S3, starting the manual punching machine, and enabling a punch of the manual punching machine to penetrate through a punch channel in the pre-pressing die to press the sheet to complete the blanking operation.

In the scheme, the pre-pressing die moves downwards and is pressed into the surface of the plate with the depth of 1/4-1/2 of the thickness of the plate.

Compared with the prior art, the invention has the beneficial effects that: the invention arranges a prepressing device above the die, the end of the prepressing die precuts a workpiece, and the punch passes through the punch channel to complete blanking and blanking of the workpiece. The invention changes the starting point of crack generation, avoids the generation of burrs of the blanking workpiece, improves the section quality of the blanking part, avoids the subsequent deburring process and improves the production efficiency.

Drawings

Fig. 1 is a schematic perspective view of a first embodiment of the present invention;

FIG. 2 is an exploded view of a pre-pressing device and a mold according to a first embodiment of the present invention;

FIG. 3 is an enlarged view of a portion of the pre-pressing device according to the first embodiment of the present invention;

FIG. 4 is a cross-sectional view of a pre-pressing mold according to a first embodiment of the present invention;

FIG. 5 is a schematic view of crack propagation during operation according to an embodiment of the present invention, wherein (a) is a schematic view of crack propagation according to the method of the present invention and (b) is a schematic view of crack propagation according to the conventional art;

fig. 6 is a schematic perspective view illustrating a second embodiment of the present invention;

fig. 7 is an exploded view of a pre-pressing device according to a second embodiment of the present invention;

fig. 8 is a schematic perspective view of a third embodiment of the present invention;

fig. 9 is an exploded view of a prepressing apparatus according to a third embodiment of the present invention.

In the figure, 1, a manual punch press; 2. a mold; 21. a platform; 22. a first through hole; 3. a pre-pressing device; 31. a base; 311. a second through hole; 312. a column; 313. a chute; 314. a third through hole; 315. a second bracket; 316. a stopper; 317. a third support; 32. pre-pressing the die; 321. a flange; 322. a base; 323. cutting edges; 3231. an inner blade face; 3232. an outer blade face; 324. a punch channel; 33. pre-pressing a handle; 331. handshaking; 332. a pressure lever; 333. a connecting rod; 334. a second bolt hole; 335. a ring-shaped structure; 34. a clamping member; 341. a first bolt hole; 342. A T-shaped slot; 343. a protrusion; 344. a third bolt hole; 345. a fourth via hole; 41. a first bolt; 42. a second bolt; 43. a third bolt; 11. a handle; 12. a slide bar; 13. a compression spring; 14. a punch; 15. a base plate; 16. a first support.

Detailed Description

In order to more clearly explain the overall concept of the invention, the following detailed description is given by way of example in conjunction with the accompanying drawings.

Example 1

As shown in fig. 1 to 4, an embodiment of the present invention provides a manual blanking apparatus, including a manual punch 1, a die 2, and a pre-pressing device 3; the die 2 is arranged on a bottom plate 15 of the manual punch press 1, and the pre-pressing device 3 comprises a base 31, a pre-pressing die 32 and a pre-pressing handle 33; the base 31 is mounted on the mold 2; the prepressing die 32 is mounted on the base 31, the prepressing die 32 is provided with a punch passage 324, the punch passage 324 is coaxial with the punch 14 of the manual punch press 1, and the punch 14 can pass through the punch passage 324; the pre-pressing handle 33 is connected to the base 31 for moving the pre-pressing die 32 downward.

With reference to fig. 1 and 2, the mold 2 is detachably mounted on the bottom plate 15 of the manual punch 1, the two sides of the mold 2 are symmetrically provided with the platforms 21, the base 31 is two identical flat plates adapted to the platforms 21, and the first bolt 41 passes through the second through hole 311 on the base 31 and the first through hole 22 on the platform 21, which is correspondingly arranged to the second through hole, so as to fix the mold 2 and the base 31 on the bottom plate 15. Other connections between the mold 2 and the base plate 15, and between the base 31 and the platform 21, such as dovetail grooves, are also possible. The base 31 is further fixed with upright posts 312, and sliding grooves 313 are formed between the upright posts 312.

Referring to fig. 2 and 3, the clamping member 34 has a T-shaped groove 342 at a middle portion thereof, the T-shaped groove 342 can receive the pre-pressing die 32, and the pre-pressing die 32 is mounted in the T-shaped groove 342 by a set screw passing through a first bolt hole 341 at the top of the clamping member 34 and contacting with the flange 321 of the pre-pressing die 32. The clamping member 34 further has protrusions 343 on both sides, and the protrusions 343 have third bolt holes 344 thereon, and the protrusions 343 can be received in the slide grooves 313 and can move up and down in the slide grooves 313. The top surface of the clamp 34 also has a fourth through-hole 345 for the punch 14 to pass through. The pre-pressing handle 33 comprises a handle 331, pressure rods 332 and a connecting rod 333, the two sides of the handle 331 are connected with the L-shaped pressure rods 332, the front positions of the middle parts of the pressure rods 332 are rotationally connected with the supports 16 symmetrically arranged on the bottom plate 15, and the front end of each pressure rod 332 is connected with the connecting rod 333. The second bolt 42 passes through the second bolt hole 334 of the connecting rod 333 to be engaged with the third bolt hole 344, and connects the preload handle 33 and the clamp 34 together. It will be appreciated that the rotational connection may be a pin connection, a bolt connection or other means as will occur to those of skill in the art.

In this embodiment, with reference to fig. 4, preferably, the pre-pressing die 32 has: a flange 321 having a circular cylindrical cross-sectional shape, a base 322, and a cutting edge 323. The cutting edge 323 includes an inner land 3231 and an outer land 3232, and is inclined such that the outer land 3232 approaches the inner land 3231, gradually becoming thicker from the end of the cutting edge 323 upward along the outer land 3232. Specifically, in this embodiment, the end of the cutting edge 323 is a sharp point, and the cross-sectional shape is a V-shape with one vertical side, so that the pre-pressing die 32 can be conveniently pressed into the workpiece plate. The included angle alpha between the outer edge surface 3232 and the inner edge surface 3232 of the cutting edge 323 is preferably 30-60 degrees. This is because, when the included angle α is less than 30 °, although the resistance when cutting into the sheet material 3 is reduced, the edge 323 is likely to be chipped, and the service life of the preliminary press die 32 is reduced. In addition, when the included angle α exceeds 60 °, the blanking force when the pre-pressing die 32 cuts into the sheet material becomes large, and in such a case, the amount of plastic deformation of the sheet material becomes large, which easily damages the surface of the sheet material other than the portion to be processed, is not favorable for the subsequent processing, and also reduces the service life of the die. From the viewpoint of satisfying both the strength of the cutting edge 323 and the low punching force, the angle α is more preferably 45 °.

It can be understood that the end of the cutting edge 323 can also be processed by an arc, so that the strength and the low blanking force of the cutting edge can be considered.

A method according to the manual blanking device, comprising the steps of:

s1, placing a substitute processing plate on the die 2;

s2, applying pressure to a pre-pressing die 32 through a pre-pressing handle 33 of the pre-pressing device 3, and enabling the pre-pressing die 32 to move downwards and cut into the surface of the plate;

and S3, starting the manual punching machine 1, so that the punch 14 of the manual punching machine 1 penetrates through the punch channel 324 in the pre-pressing die 32 to press the plate to complete the blanking operation.

Preferably, the pre-pressing die 32 moves downwards and is pressed into the surface of the plate to the depth of 1/4-1/2 of the thickness of the plate.

When the pre-pressing die 32 presses the plate, the handle 331 is grasped to lift the pre-pressing handle 33 forward, at this time, the pressure lever 332 drives the connecting rod 333 to move downward, the connecting rod 333 drives the clamping piece 34 through the second bolt 42 to move along with the clamping piece, and finally the pre-pressing die 32 moves downward, and when the pre-pressing die 32 presses the plate, stress concentration is generated at a contact part of a blade tip and the plate. The handle 11 is then pulled downwards, the handle 11 carrying the slide 12 compressing the spring 13 downwards, bringing the punch 14 progressively closer to the slab. Eventually the punch 14 comes into contact with the sheet and begins to apply pressure to the sheet. Along with the continuous increase of pressure, the position of stress concentration can take lead to produce the microcrack, and the crackle is constantly expanded afterwards to final and 2 cracks of die department of mould converge, make the metal work piece sheet material produce the fracture separation. As shown in fig. 5 (a), since the starting point of the generation of the crack is changed from the edge side slightly away from the punch tip to the vicinity of the tip of the prepress mold 32, the merging path of the crack is changed, and the surface of the blanking member has no metal residue caused by the merging of the crack and no burr, so that the quality of the section of the blanking member is high, further deburring is not needed, the production cost is saved, and the production efficiency is increased. In addition, the pre-pressing die 32 is sleeved outside the punch 14 and is coaxial with the punch 14 during working, so that the processing precision of the plate can be guaranteed, and the processing error caused by moving the plate is avoided. Fig. 5 (b) shows a conventional technique, in the blanking process, with the increasing of the pressure applied to the sheet by the punch 14, extremely tiny fracture cracks are generated in the metal materials in the side areas of the cutting edges of the female die and the male die, and then the cracks are continuously expanded and finally converged, so that the metal sheets are fractured and separated; however, since the starting point of the crack generation is not at the edge of the die but at the side surface of the cutting edge slightly away from the edge, when the crack penetrates through, excess metal with different heights and thicknesses remains on the edge of the surface of the blanking part, and burrs are formed. Compared with the prior art, the invention arranges the pre-pressing device above the die, the end of the pre-pressing die precuts the sheet material, and the punch passes through the punch channel to complete blanking and blanking on the sheet material. The invention changes the starting point of crack generation, avoids the generation of burrs of the blanking workpiece, improves the section quality of the blanking part, avoids the subsequent deburring process and improves the production efficiency.

Example 2

The second embodiment of the present invention, as shown in fig. 6 to 7, differs from the above-described example 1 in that: in this embodiment 2, the upper ends of the bases 31 on both sides of the mold 2 are connected by a flat plate to form an Ω shape, the flange 321 of the pre-pressing die 32 is located above the third through hole 314, and the base 322 of the pre-pressing die passes through the third through hole 314; second brackets 315 are respectively arranged at the top of the flat plate and positioned at two sides of the third through hole 314; the pre-pressing handle 33 is two L-shaped rods, the pre-pressing handle 33 is rotatably connected with the second support 315, and one end of the pre-pressing handle 33 is located above the pre-pressing die 32, so that the pre-pressing die 32 can be pressed down.

In operation, the end of the prepressing handle 33 far away from the prepressing die 32 is held to lift the prepressing handle 33 upwards, and the other end of the prepressing handle 33 presses the prepressing die 32 to move downwards and finally press the prepressing die into the plate. Then the handle 11 is pulled downwards, the handle 11 drives the sliding rod 12 to compress the spring 13 to move downwards, so that the punch 14 gradually approaches the sheet material and finally the blanking operation is finished.

Example 3

The third embodiment of the present invention, as shown in fig. 8 to 9, differs from the above-described example 1 in that: in this embodiment, the pre-pressing handle 33 is a rod provided with a ring-shaped structure 335; a stop block 316 is arranged on the base 31 on one side of the die 2, and a third bracket 317 is arranged on the base 31 on the other side;

one end of the prepressing handle 33 close to the annular structure 335 is rotatably connected with the third support 317 through a bolt, a through hole is formed in the middle of the annular structure 335, a plurality of bolt holes are circumferentially distributed in the middle of the annular structure 335, the lower end of the prepressing die 32 penetrates through the through hole, the upper end flange 321 is connected with the bolt hole of the annular structure 335 through the third bolt 43, the prepressing die 32 is fixed on the prepressing handle 33, and the other end of the prepressing handle 33 is located above the stop block 316.

In operation, the end of the pre-pressing handle 33 away from the ring-shaped structure 335 is held and pressed downward, and the pre-pressing die 32 is pressed into the workpiece plate, until the movement of the pre-pressing handle 33 is limited by the stop 316, and the pre-pressing die 32 is coaxial with the punch 14. Then the handle 11 is pulled downwards, the handle 11 drives the sliding rod 12 to compress the spring 13 to move downwards, so that the punch 14 gradually approaches the sheet material and finally the blanking operation is finished.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. A manual blanking device comprises a manual punch (1) and a die (2), wherein the die (2) is arranged on a bottom plate (15) of the manual punch (1), and the manual blanking device is characterized by further comprising a pre-pressing device (3), wherein the pre-pressing device (3) comprises a base (31), a pre-pressing die (32) and a pre-pressing handle (33); the base (31) is mounted on the mold (2); the prepressing die (32) is arranged on the base (31), the prepressing die (32) is provided with a punch passage (324), the punch passage (324) is coaxial with a punch (14) of the manual punch press (1), and the punch (14) can penetrate through the punch passage (324); the prepressing handle (33) is connected with the base (31) and is used for enabling the prepressing die (32) to move downwards;

a flange (321) is arranged on the outer circumference of the upper end of the pre-pressing die (32), a cutting edge (323) is arranged at the tail end of the pre-pressing die, and a base (322) is arranged between the flange (321) and the cutting edge (323); the cutting edge (323) comprises an inner edge surface (3231) and an outer edge surface (3232), the inner edge surface (3231) is the inner wall of the punch channel (324), and the tail end of the cutting edge (323) is a tip which is inclined inwards along the outer edge surface (3232) and becomes thinner gradually;

a first bolt (41) penetrates through a second through hole (311) in the base (31) and a first through hole (22) which is correspondingly arranged in the mould (2) to fix the mould (2) and the base (31) on the bottom plate (15);

the outer edge surface (3231) and the inner edge surface (3232) form an included angle alpha, and the included angle alpha is 30-60 degrees.

2. Manual blanking apparatus according to claim 1, wherein said pre-stressing means (3) further comprises a clamp (34); the clamping piece (34) is provided with a fourth through hole (345) and a T-shaped groove (342) for accommodating the prepress mold (32); the flange (321) and base (322) of the pre-die (32) are mounted within a T-shaped slot (342); the fourth through hole (345) is communicated and coaxial with the punch passage (324) of the pre-pressing die (32); the two sides of the clamping piece (34) are connected with the base (31) in a sliding way; the base plate (15) is provided with a first support (16), the prepressing handle (33) is rotatably installed on the first support (16), and the tail end of the prepressing handle (33) is connected with the two sides of the clamping piece (34).

3. Manual blanking device according to claim 2, characterized in that the holder (34) is provided with protrusions (343) on both sides, that on the base (31) on both sides, a post (312) is provided, respectively, that the post (312) is provided with a runner (313), and that the protrusions (343) can be moved up and down in the runner (313) of the post (312).

4. The manual blanking apparatus of claim 3, wherein the pre-pressing handle (33) includes a grip (331), a pressing rod (332), and a connecting rod (333), the grip (331) is connected to one end of the pressing rod (332), and the other end of the pressing rod (332) is connected to the holder (34) through the connecting rod (333); the first bracket (16) is rotatably connected with the pressure lever (332).

5. The manual blanking apparatus of claim 1, wherein upper ends of the bases (31) on both sides of the die (2) are connected to form an omega shape by a flat plate, a third through hole (314) is formed at a top of the flat plate, a flange (321) of the prepress die (32) is positioned above the third through hole (314), and the base (322) of the prepress die passes through the third through hole (314); second brackets (315) are respectively arranged at the top of the flat plate and positioned at two sides of the third through hole (314); prepressing handle (33) are two L-shaped rods, prepressing handle (33) is respectively connected with second support (315) in a rotating mode, one end of prepressing handle (33) is located above prepressing die (32), and prepressing die (32) can be pressed down.

6. Manual blanking device according to claim 1, wherein the pre-pressing handle (33) is a rod provided with a ring-shaped structure (335); a stop block (316) is arranged on the base (31) on one side of the die (2), and a third support (317) is arranged on the base (31) on the other side;

one end of the prepressing handle (33) close to the annular structure (335) is rotatably connected with the third support (317), the annular structure (335) is provided with a through hole, the lower end of the prepressing die (32) penetrates through the through hole, an upper end flange (321) is connected with the annular structure (335), and the other end of the prepressing handle (33) is positioned above the stop block (316).

7. Method of manual blanking apparatus according to any of the claims 1-6, characterized by the following steps:

s1, placing a plate to be processed on the die (2);

s2, applying pressure to a pre-pressing die (32) through a pre-pressing handle (33) of the pre-pressing device (3), and enabling the pre-pressing die (32) to move downwards and press the pre-pressing die into the surface of the plate;

and S3, starting the manual punching machine (1) to enable a punch (14) of the manual punching machine (1) to penetrate through a punch channel (324) in the prepressing die (32) to press the sheet metal to complete the blanking operation.

8. Method of manual blanking apparatus according to claim 7, characterized in that the pre-press die (32) is moved downwards and pressed into the slab surface to a depth of 1/4-1/2 of the slab thickness.