JPS60187437A - Slag holding dice - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates generally to the field of workpiece machining operations, and specifically to punch press machines.

"Slap tension" is a recurring problem in high-speed punch press operations.

"Slap" is each piece of metal punched from the workpiece during a punching operation, and "slap tension" is the tendency of the slap to follow the head of the punch on its return stroke, so Slap rising to or near the plane of the die creates problems in subsequent punching operations when the workpiece moves rapidly between the punch and die. Slap tension problems are particularly serious when small punches and dies are used and can result in significant wasted time and production losses. The loss of production is particularly evident in view of the fact that modern punch presses often operate in the range from about 200 strokes per minute to about 400 strokes per minute.

Historically, the die hole size is set to a value that exceeds the hole size to be punched into the workpiece by about 8% of the workpiece thickness. Therefore, since the diameter of a punched hole increases from the punch side to the die side of the workpiece, the punch side of the hole has the dimensions of the punch, and the die side of the hole has the dimensions of the die. Anyone can notice that it has a diameter of . The resulting slap has an overall dimension larger than the dimension on the punch side of the punched hole, so that as the slap follows the punch during the return stroke of the punch, it will move into the punched hole. It is not uncommon for the workpiece to wedge or become stuck and impede continued movement of the workpiece. It is necessary to frequently resharpen the tip of the punch, but if the size of the hole in the die increases to the extent that the size of the hole to be punched in the workpiece exceeds 20% of the thickness of the workpiece, It is known that the propensity to blunt the tip diminishes. As a result, the size of the hole in the die also increases, making the slap tension problem even more significant by further increasing the dimensional difference between the punch side and the die side of the punched hole.

Various measures have been taken to reduce or prevent slap tension problems. To separate the slap from the punch head end, a slap ejection rod can also be mounted in the center of the punch eye to eject the slap from the die during each punching cycle. It is also expensive to construct a punch head equipped with a separately movable discharge bin, and such devices do not give very good results;
This solution to the slap tension problem has not been widely generalized.

Other solutions include the use of thickened grease in the die to stick the slap to the die and prevent it from following the punch head during its return stroke. included. This solution to the slack tension problem has also not been widely generalized.

The present invention relates to a slug-retaining punching die having a hole that mates with a punch during the punching and retraction stages of a material punching operation.

The die extends in the direction of movement of the punch to impact against and grip the peripheral edge of the punched slap of the workpiece material during the punching phase, and to cause the slap to follow the punch during the retraction phase. and at least one inwardly extending protrusion adapted to inhibit this.

In a preferred embodiment, the die includes a number of such protrusions spaced from each other around the periphery of the die hole and spaced downwardly from the surface of the die in the punch.

Preferably, each gripping projection extends into the interior of the die to a point sufficient for each such projection to abut only the enlarged periphery of the slap. As used herein, the "extended periphery" of a slap is that portion of the periphery of the slap that extends beyond the dimensions of the associated punch, such that the dimension of the slap across the surface of the slap facing the punch is Please note that the dimensions are slightly smaller than the dimensions of the other surfaces of the slap.

Referring first to FIGS. 2-5, the die and punch are designated by the symbols 12 and 14, respectively, and the die 12 has a generally circular die hole 12.1. Although, for ease of understanding, the embodiment of the invention typically illustrated in FIGS. 1-10 will be described in terms of circular dies and circular punches, the dies and punches may be of various shapes known in the art. I would like you to understand that it can be something like this.

As shown in FIG. 2, the die hole 12.1 has a diameter slightly larger than the diameter d of the punch 14, but the difference in diameter depends on the thickness of the material to be punched, and typically This ranges from perhaps 8% to about 20% of the thickness of the workpiece. A circular hole 12 formed through the die 12
．． 2 is preferably of the same diameter as the die hole 12.1, but the die and punch are made of common hardened steel or hardened alloy steel with a diameter equal to the die hole 12.1, and the lower end face of the punch 14 is sharpened. It should be understood that it has an edge 14.1.

Small projections, indicated by the symbol 16 in FIGS. 2-5, extend inside the die hole 12.2, but each of the small projections is formed on opposite sides of the die hole. In the embodiments shown in FIGS. 1 to 5, each protrusion 16 has an upper (first
When viewed from the figure), the shape is roughly triangular, and its tip forms a sharp +U apical edge 1 & 1. Each protrusion 16 preferably extends long in the direction of movement of the punch in the die bore 12.2 and extends a short distance downwards from the upper surface of the die bore, for example approximately the thickness of the workpiece to be punched. It is preferable that the die hole be spaced downwardly from the upper surface of the die hole by the same amount as the die hole.

Each projection 16 also preferably extends downwardly from the bottom surface 12.3 of the die to a point spaced upwardly, the length of each projection 16 being equal to the thickness of the workpiece to be punched. It is desirable to set the value to about 0.5 times to about 1.5 times as much as possible. It is desired that the diametrical spacing between the sharp top edges 1 & 1 of each protrusion is not less than the diameter d of the punch 14. The partial profile of the punch when centered on the die is illustrated in FIG. 1 by dashed line 14.2.

As a background, the punch press machine removes sludge from the workpiece.
Punch 14 centered over die 12 to cut
It should be understood that a ram (not shown) is commonly used which impinges from above. The die is typically rigidly fixed and the punch is typically reciprocatably mounted within the punch sleeve. The punch may be equipped with a release plate (not shown) and a release spring to facilitate upward removal of the punch from the workpiece during the retraction phase of the punching cycle. During a typical punching operation, the workpiece is advanced between the top of the die and the bottom of the punch. The ram is struck down by the punch with great force, but first the punch and punch guide are struck from above against the workpiece, and in the same stroke the punch is pushed downward until the punch penetrates the workpiece. Keep driving. As the ram retreats upward in the η~' direction, the workpiece is peeled off, pulling the B prench upward and pulling it out of the hole formed in the workpiece, but the peeling plate prevents the workpiece from following the rising punch. Therefore, it operates to hold the periphery of the workpiece. The punch and punch guide are then retracted slightly upwards to allow introduction of a new section of workpiece between them and the die. This -membrane type stamping operation is well followed in the art, as exemplified by Willung and Rosen, US Pat. No. 4,248,111.

Since the size of the die hole is generally slightly larger than the size of the punch, the size of the hole formed on the punch side of the workpiece should be slightly smaller than the size of the hole on the die side of the workpiece. The workpiece designated by the symbol W in FIG. 3 has a punch side designated by the symbol P and a die side such as the symbol P. FIG. 3 shows the punch 14 as it passes through the thickness of the workpiece W during the punching cycle.

In the position of the punch shown in FIG. 5, the slug 18 has been completely severed from the workpiece, even though the punch has not passed through the entire thickness of the workpiece, so that the edge 14.1 of the punch The tapered edges of the workpiece and the sludge caused by the difference in the dimensions of the die hole 12.1 and the die hole 12.1 can be clearly seen. It is understood that for clarity, the dimensional differences between the punch and die are exaggerated in Figures 1-6 to show the tapered edges of the sludge and workpiece holes. I want to have it.

In FIG. 4, the punch is shown in a position where it has passed through the entire thickness of the workpiece, and the sludge 18 has now been completely separated from the workpiece. As the punch continues to advance downwardly, the enlarged annular periphery of the sludge (designated by the symbol E in the drawing) abuts and is skewered onto each protrusion 16 of the die 12. As can be seen, each protrusion 16 only extends into the enlarged annular periphery E of the sludge which extends beyond the dimension of the edge 14.1 of the punch.

As a result, the annular periphery E of the sludge 18 is slightly deformed so that the sludge is retained in the die in the position shown in FIG. The punch will now retract upwards as previously described, allowing a new section of workpiece to be inserted between the punch and the die. In the subsequent punching operation, the sludge 18 is pushed down from between each projection 16, so that the annular periphery E of the sludge adjacent to the bottom end of each projection is pushed down beyond its bottom end, so that the sludge no longer remains in each projection. Please understand that it can fall freely from the die without being held by the protrusions. Although the vertical length of each protrusion 16 can be varied arbitrarily as desired, for efficiency reasons this length is such that at any given time more than one piece of sludge can be stacked in the die and attached to each protrusion. It is desirable to prevent it from being held too tightly. As new slaps are punched and skewered onto each projection, the slaps from the previous punching step are freed from each projection and fall from the die.

It should be appreciated that the punch 14 must advance far enough in its downward stroke to cause the slap 18 to skewer each projection 16. The length of travel of the punch and the spacing of each projection downward from the top surface of the die hole 12.2 can be adjusted as desired to achieve this purpose.

The embodiment of FIGS. 1 and 3-5 includes a pair of diametrically opposed projections 16 within the periphery of the circular die hole. Particularly for smaller die holes, it is only necessary to use one protrusion, so that the slap is skewered over the protrusion on one side during its descent, and
Please understand that it is firmly held against the die hole on the opposite side. Particularly for larger die holes, a large number of protrusions are used and are spaced at appropriate intervals around the periphery of the die hole (equally spaced circumferentially in the case of a circular die hole).

Referring again to FIG. 2, although each protrusion 16 extends downwardly as previously discussed, it is preferably spaced upwardly from the bottom surface 12.3 of the die. In a preferred embodiment, the dimensions of the portion 12.4 of the die hole extending below each projection 16 are such that the slap extends below each projection 16.
The die hole 12.1 is slightly larger than the die through hole 12.2 adjacent to the die hole 12.1 in order to provide a preferably outwardly tapered slap outlet to allow it to fall freely from the die once free from the die hole 12.1. The diameter is expanded.

The distance that the protrusion 16 extends into the die through hole largely depends on the clearance between the punch and the die hole, that is, the difference in relative dimensions between the punch and the die hole.

For example, the clearance between the punch and die hole shown in FIG. 2 should be the difference between the diameter and d. In order to contact and deform the periphery of the slap over its entire thickness, each protrusion should preferably expand the slap, even if one or more protrusions extend inside the die through-hole. It only contacts and deforms the peripheral edge. Generally, it is desirable for the dies and punches of the present invention to have a workpiece thickness in the range of about 0.7 mm to about 7 mm, and that each protrusion used extends from about 0.02 mm inwardly from the die through-hole. Approximately 0.
Workpieces with a wide range of thicknesses can be handled, even if they extend over distances ranging up to 9 m. For a workpiece of such thickness, the distance that each protrusion must extend inward in the die through hole *<protrusion extension degree) can be approximately calculated using the following formula: can.

Projection extension i/2 x clearance - 0.025i + t In a typical punching operation, the diameter of the circular punch may be 2 m and the thickness of the workpiece may be 1 mm. If the die diameter exceeds the punch diameter by 20% of the workpiece thickness, then the die diameter is approximately 2.
02m, the clearance is 0.2m, and the radial width of the enlarged annular periphery E of the slap (Fig. 6) is approximately 0.02m.
It should be 1M. Assuming that the diameter of the die through hole 122 (FIG. 2) is the same as the diameter of the die hole 121, the top edge 16.1 of each protrusion 16 extends radially inward of the through hole by 4 x approximately 0.211y. -0,025m Fertilization Q, 0
It should extend by a distance of 75 as.

As a result, the trapezoid formed by this die on the periphery of the slap must be very narrow and extend upwardly along the periphery only within the enlarged annular periphery of the slap. That is, the upper surface of the slap, which is in the same manner as the punch, is not contacted by the respective protrusions. Preferably, each projection extends inside the die such that it projects into the enlarged periphery a distance ranging from about 40% to about 80% of the width of the enlarged annular periphery of the slap.

Referring to FIGS. 7 and 8, a die 20 similar to that shown in FIGS. 1 and 2 is shown, but with each protrusion extending inside the die through hole 20.2. 20
．． 1 is generally square in shape when viewed from above and therefore has a pair of sharp side edges for gripping the annular portion E of the slap, only one of which is designated by the symbol 20.3. has been done. The embodiment of FIGS. 9 and 10 is similar to that of FIGS. 7 and 8, with the die 22 in this embodiment having a generally rounded shape extending inside its through hole 22.2. Alternatively, the protrusion 2Z1 has a semicircular cross section. Referring now specifically to FIG. 10, in order to more easily insert the slap, if desired, note - Q22.
3. You can make the upper part tapered as specified by the hair.

As already pointed out, each die according to the invention has a die hole of various shapes and dimensions, and a number of variously shaped protrusions extending into the interior of the hole through the die can be used. . Dice 24 shown in Figure 11
has a generally rectangular hole 24.1 extending through its thickness, each side wall 24.2 of the hole having six protrusions 24 spaced substantially equally spaced below the top surface of the die. .3 are provided to protrude inwardly, and each protrusion is formed into a generally triangular shape when viewed from above.

Although each protrusion may be added to an existing die by means such as welding, each die including each protrusion according to the present invention is preferably made from one sheet of steel or other metal sheet with a hole in the die, In order to form the through holes and the respective protrusions, it is preferable that the original plate is manufactured integrally by a known electric discharge machining method in which electric discharge from both electrodes erodes the original plate.

When a die hole, as shown by symbol 12.1 in Figure 2, becomes dull during repeated use, the sharpening process involves polishing the top surface of the die to obtain a new, sharp edge of the die hole. Machining operations typically involve cutting or milling. The thickness of the die therefore decreases slightly and gradually.

Since each protrusion 16 is spaced downwardly from the top surface 125 of the die, each typical die has its respective protrusion side 916
．． The sharpening operation can be redone several times before reaching the top edge of 1. When the top edge is reached, the top edge of each protrusion becomes polished on itself such that each protrusion maintains the desired vertical spacing between itself and the top surface 12.5 of the die.

Although preferred embodiments of the invention have been described, it will be appreciated that various changes, adaptations and modifications may be made to the invention without departing from the spirit of the invention or the scope of the appended claims. Must-have.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view of a die according to the invention. FIG. 2 is a partially schematic longitudinal sectional view of a punch and die according to the invention. FIG. 3 is a partially schematic longitudinal cross-sectional view of the punch and die of the present invention, showing the entry of the punch into the workpiece during the punching operation. FIG. 4 is a cross-sectional view similar to FIG. 3, but showing the punch extending further into the die. FIG. 5 is a cross-sectional view similar to FIGS. 5 and 4, but showing the punch extending further into the die. FIG. 6 is a partially enlarged longitudinal sectional view of the slap. FIG. 7 is a partial top view showing a different example of the die according to the present invention. FIG. 8 is a partial vertical sectional view taken along arrow line 8-8 in FIG. FIG. 9 is a partial top view showing still another variant of the die according to the present invention. FIG. 10 is a partial vertical cross-sectional view taken along the arrow line 10-10 in FIG. FIG. 11 is a plan view showing still another variant of the die according to the present invention. 12, 20.22.24: Dice, 14: Punch, 1
6.2α1, 22.1.24.5: Protrusion, 18 Nislug, 12.2,2α2.22.2.24.1: Die through hole (dice hole) D: Diameter of die hole, d: Punch diameter Diameter, E: Enlarged annular periphery, W: Workpiece, P: Bonte side surface, F: Die side back side Patent applicant Nidwin Tee, Shuttle Laose Wilson
Tools Company Agent Yumi Kaede (and 1 other person) Fang 1 Diagram Procedure Amendment (Method) 1 Indication of the case 1982 Patent Application No. 43708 2 Name of the invention Slug holding die 3 Relationship with the amended person case Patent applicant name: Wilson Tool Company (and others) 5. Date of amendment order: May 9, 1982
, Contents of amendment (1) Submit an application for correction. (2) Submit a power of attorney and a translation. (3) Submit the revised specification. (No change in content)

Claims (1)

[Scope of Claims] (1) A punch press machine comprising a punch and a die having a hole that fits with the punch during a punching stage and a drawing stage in a material punching operation, the die having a extending in the direction of movement of the punch so as to strike against and grip the peripheral edge of a punched slap of the workpiece material during the punching step, and to grip the peripheral edge of the punched slap during the retraction step; A punch press characterized in that it includes at least one inwardly extending protrusion adapted to inhibit tracking. (2) The bundle is further characterized in that at least one inwardly extending protrusion is spaced apart in the direction of travel of the punch from a face of the die that normally faces the punch. Punch press machine according to claim 1. (3) Claim 1 further characterized in that said die has at least two such protrusions.
) The punch press machine described in section 2.). (4) The die according to claim (3), wherein each of the protrusions is spaced apart around the inner peripheral surface of the hole of the die. 5. A punch press according to claim 1, further characterized in that each of the protrusions includes a rounded slap contact surface. (6) A punch press according to claim 11, further characterized in that at least one protrusion of the bundle has a sharply shaved slap contact surface. (7) The protrusion of claim 11. A punch press according to claim 1, further characterized in that said bundle has at least two sharp side edges for contacting said slap. A punch press according to claim 1, further characterized in that the protrusion is formed as an integral part of the die. (9) The die is normally moved away from the punch. Claims further characterized in that the inwardly extending protrusion of at least one of the bundles is spaced apart from the second face of the die in the direction of movement of the punch. Punch press machine according to paragraph (1).Head characterized in that the dimensions of the holes in the second side of the die are larger than the corresponding dimensions of the holes in the side of the die that normally faces the punch. A punch press machine as set forth in claim (9), further characterized in %. 0η A punch press machine as set forth in claim (1), further characterized in that the die includes a single protrusion. (6) A botch press machine consisting of a botch and a die having a hole that fits with the punch during the punching stage and drawing stage of the material punching operation, and the size of the hole of the die is the same as that of the punch. a punch press machine in which an enlarged annular periphery corresponding to the difference between the dimensions of the punch and the hole of the die is formed in the slap of the workpiece material,
The die is arranged so as to contact and grip only the enlarged annular periphery of the slap formed during the punching step, and to inhibit the slap from following the punch during the retraction step. A punch press machine, characterized in that it has at least one inwardly extending protrusion. (2) Claim 02 further characterized in that at least one protrusion of said bundle is spaced from a surface of said die normally facing said punch in the direction of movement of said punch. punch press machine. a→ At least one protrusion of the bundle extends inside the hole of the die by a predetermined dimension, and the dimension is measured in the direction of the inner ground of the at least one protrusion of the bundle. 2 of the difference between each dimension of and the hole of the die.
The punch press machine according to claim 02, further characterized in that the punch press size is less than 1/2.