JPH10128477A - Cup forming method and tool device used in double acting mechanical press - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the load applying on an outside ram and to raise the press speed by inserting inserting members of different thickness onto a cut edge die and blank/draw dies of plural numbers of multi stages of a double acting mechanical press and displacing the timing applied with the load. SOLUTION: Tools of plural numbers of multi-stages are divided in several sets of timing groups. For example, these are grouped to a 1st to 4th stages. The thickness of an inserting member 120 of each stage is made different. Supplying sheets are clamped with stock plates 110 of the 1st to 4th stages and cut edges 78. The sheet is cut between the cut edge 78 and the blank/draw die 90, and a blank B is made. The blank B is clamped with a draw pad 70 and the blank/draw die 90. A die center punch 38 is lowered, the blank B is drawn and a cup is made. Objects to be machined are clamped always, and these are machined with displacing its timing every 1st to 4th stage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a series of cups from a strip of metal sheet at each stroke of a double-acting mechanical press, and to a tooling thereof.

[0002]

2. Description of the Related Art When manufacturing cups and cans in the can industry, for example, US Pat. 4,020,670, N
o. 4,248,076 and 4,416,14
A double-acting mechanical press with a general type of cup-forming tool as disclosed in US Pat.
Presses for forming such cups are available from 150 to 200
It generally operates within the range of strokes per minute (spm) and has a plurality of cup forming tool parts to form a batch of cups at each stroke of the press.

[0003]

In order to respond to the increasing demands on manufacturing in the can industry, it has been desired to operate a cup forming press at a high speed, for example, 220 to 25 spm. . However, such an increase in the speed of the cup-forming press results in a very high dynamic load on the press, especially the compression and tension loads on the outer ram of the double-acting press. Due to such an increase in the dynamic load on the press, a load exceeding the specified level is applied to the press, and the components of the press are damaged.

[0004] Blanking and cutting a plurality of parts by positioning each punch slightly above the sheet metal workpiece in each press stroke from the sheet metal workpiece. It is known in the tool and can industry to configure punches and dies to do so. According to this, blanking or punching of parts can be performed continuously, but the support of the workpiece is performed not for continuous but for each plate.

SUMMARY OF THE INVENTION The present invention provides an improved tool for forming and operating a press tool such that a cup-shaped article can be formed at each stroke of the press at a high production rate without overloading the pressed part. Provided is a method and apparatus. For example, a cup-forming press with a tool constructed in accordance with the present invention can reduce the compressive force or load on the outer ram to 50% or less, so that the specified load of the press can be reduced within the voice at the press speed. About 150 spm
To about 250 spm.

[0006]

According to one embodiment of the present invention, a cup forming press includes a multi-stage tool, each tool stage comprising a series of opposed annular blank / draw dies. And an annular draw pad of
It has an annular cut edge die surrounding each draw pad and a die center punch in each draw pad. The stages of these tools engage the metal sheet in a precise timing sequence that continuously squeezes a series of circular blanks between the cut edge die and the corresponding blank / draw die during each stroke of the press. The blank is continuously held between the draw pad and the corresponding blank / draw die, and the blank is connected to the cup by the die center punch extending into the corresponding blank / draw die. It is configured to squeeze. Also according to the present invention, existing cup forming press tools provide a series of annular inserts and retainers for cut edge dies on some of the drawpads and a number of blank / draw dies. It can be easily changed by lowering the holding member that supports this. The tool at each stage may have a pressure sleeve surrounding the bottom panel punch in a blank / draw die to form a reshaped boss in the bottom wall of each cup. The invention also allows the upper and lower components of the tool to be conveniently and quickly removed after a trial period for maintenance of the tool.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a bottom view of a system 15 of 14 cup forming tools, ie, a plan view of a bottom tool. The system 15 comprises a bed 20 of a double-acting mechanical press.
It has a lower die 18 attached to it (FIG. 2). The press also includes an inner ram 22 and an outer ram 24, the inner ram 22 having a vertical stroke of, for example, about 5 inches (about 12.7 cm), and the outer ram 24 having a vertical stroke of, for example, 2 inches. (Approximately 5.08 cm). As shown in FIG. 1, the lower dish 18 has fourteen holes, or pockets 2, extending vertically through the lower dish 18 and into the cup discharge chamber 28.
6. These pockets 26 are
13 and 14 constitute the first stage, and pockets 3.
4.1.11 constitutes the second stage, the pockets 5, 6, 9, 10 constitute the third stage, and the pockets 7, 8 constitute the fourth stage (four stages). 1).

The inner ram 22 (FIG. 2) supports the upper, that is, the inner die 32. A series of vertical rises 3
4 is attached to the bottom surface of the inner die 32 and extends downward so as to be vertically aligned with the corresponding pocket 26. A die center punch 38 (FIG. 3) is attached to a lower end of each vertical rising portion 34 by a center screw 39 and a precision positioning pin 41. Each die center punch 3
8 supports the hardened wear-resistant outer sleeve 42. Each of the vertical rising portion 34 and the corresponding die center punch 38 has an air passage 44 extending in the vertical direction. The air passage 44 has compressed air at a time when the cup is removed from the punch. (Pressurized air) is supplied. As is apparent from FIG. 2, the vertical rising portion 34 and the corresponding die center punch 38 are supported by the inner ram 22 via the mounted inner die 32 and moved in the vertical direction.

Since the tool elements for each pocket 26 are substantially the same, only the tool elements for one pocket are shown in FIG. A cylindrical guide sleeve 46 (FIG. 3) is provided on the outer periphery of the vertical riser 34 and has an upper flange attached to an annular plate 48 mounted on an upper die 52. On this dish 52
Are supported by the outer ram 24 by a plurality of screws 54 (FIG. 2) which are circumferentially separated from each other. Cylindrical liner 5
7 is lined with a hole formed in the upper die 52,
It cooperates with the guide sleeve 46 as well as the annular plate 48 to define a fluid or air chamber 59 which receives the head of the piston 62. The head supports a wear-resistant pad (not shown) in a plurality of holes 63 formed at intervals in the circumferential direction, and has a plurality of screws 66 spaced apart from each other in the circumferential direction. It is defined in the air chamber 59 by an annular holding member 64 attached to the upper die 52 by the positioning pin 67.

A draw pad (throttle pad) 70 composed of two sections is supported so as to slide vertically in a holding member 64 below the piston 62. On the bottom surface of the draw pad 70, a plurality of narrow concentric grooves or recesses are formed so as to make this surface an irregular surface. The lower part of the draw pad 70
It is formed of a harder steel than the upper part having a plurality of holes 73 which are engaged with the piston 62 and are formed at a predetermined circumferential interval and support a wear-resistant pad (not shown). The draw pad 70 is supported in the annular holding member 64 by a holding member 74 having an annular cut edge attached to the holding member 64 by a plurality of screws 77 arranged at intervals in the circumferential direction. ing. The holding member 7
4 supports a hard annular shear die (shear type) surrounding the draw pad 70, that is, a cut edge 78.
A rigid flat spacer ring 82 is inserted into a recess formed in the upper portion of the holding member 74 to form a downward movement restricting member for the draw pad 70.

As shown in FIG. 3, each hole or pocket 26 in lower die 18 is vertically aligned with a corresponding die center punch 38 and is slightly larger in diameter. A two-part blank / draw die 90 is provided for vertical alignment with each of the pockets 26 in the lower die 18. The die blank / draw die 90 is supported in a circular recess of an annular holding member 93 by a flat annular spacer 96. Each blank / draw die 90 is attached to a corresponding retaining member 93 by a set of circumferentially spaced screws 98, and another set of screws 101.
Accordingly, each holding member 93 is attached to the lower die 18. The spacer 96 is attached to the blank / draw die 90 by a set of screws 102. A plurality of locating pins and bushes (not shown) are also used to accurately position each blank / draw die 90 and its retaining member 93 on the lower die 18. As shown in FIG. 3, the upper portion of the blank / draw die 90 is comprised of a rigid ring inserted into the lower portion thereof and forcibly held therein.

As shown in FIG. 4, the die center punch 38 constituting the upper tool of the upper die and the draw pad 70
, Holding member 74, cut edge 78, piston 6
2 and the holding member 64 are a central screw 39 and a screw 66
And the screw 77 can be conveniently and quickly removed from the upper die 52 by simply removing it. In addition, these components can be removed to replace components such as wear resistant pads and piston seal rings without moving the upper die 52 further up or disassembling the upper tool further.

Referring to FIGS. 2 and 3, a flat stock plate 110 forms the bottom, ie, part of the lower tool,
A circular opening, ie, a gap hole 111, for receiving each of the blank / draw dies 90 therein is defined. This stock plate 110 has a series of spring-loaded pistons 115
2 (FIG. 2), the upper surface is supported so as to be substantially flush with the upper surface of the blank / draw die 90. These pistons 115, as shown in FIG.
Lower die 1 between and around draw dies 90
8. In addition, these pistons 115
Urges the stock plate 110 to the raised position (FIGS. 2 and 3) with a predetermined force, but when the force is applied by the downward movement of the cutting edge 78 and the holding member 74, the friction is slightly increased The stock plate 110 is set so that it can move downward.

Next, as shown in FIGS. 5 to 8, FIG.
Or the multi-stage tool described with reference to FIG.
The plurality of sets of holes, or pockets 26, are operated to perform a continuous blanking, holding, and drawing operation. These continuous operations are performed by accurately positioning the stages of the blank / draw die 90, the draw pad 70, and the die center punch 38 at a predetermined height with respect to the bed 20. For example, by grinding some of the bottom surfaces of the holding member 93 to lower the blank / draw die 90 and adding a set of inserts to the upper tool for each of the second, third and fourth stages. Existing cup molding tools can be modified.

As shown in FIG. 3 which shows the tool stage 4 shown in FIGS. 1 and 2, the flat annular insertion member 120 includes:
Another flat annular insert 121 regulates the downward movement of the air-actuated piston 62 pressing the draw pad 70 at a predetermined pressure, defining the downward movement of each draw pad 70 relative to the cut edge 78. I do. Further, another flat annular insertion member 122 is provided for supporting vertical rising portion 34.
The height of the die center punch 38 relative to the draw pad 70 is accurately determined by spacing, ie, lowering, some of the die center punches 38 with respect to the die center punch 38.

For example, as shown in the table of FIG. 8, a blank / draw die 9 for the holes of the first and second stages.
The 0's have each been lowered by 0.012 inches (about 0.030 cm). Such a reduction is achieved by grinding the bottom surface of the holding member 93 supporting the blank / draw die 90. Stage 2 pocket 3,
The inserts 120, 121 for 4, 11, 12 have a.
It has a thickness of 020 inches (0.051 cm), so that the piston 62 for the stage 2 pocket and the corresponding draw pad 70 correspond to the stage 1, pockets 1, 2, 13, 14 Located 0.20 inches above the piston 62 as well as the draw pad 70.
The die center insert 122 for the stage 2 pocket 3.4.11.12 is 0.060 inch (0.152c).
m), so that the die center punch 38 for these pockets is located 0.060 inches below the die center punch 38 of the stage 1 pocket.

As is apparent from the table of FIG.
Inserts 120 for pockets 5,6,9,10 of
121 has a thickness of 0.052 inches (0.132 cm) so that the pistons 62 for these pockets
And the draw pad 70 are located 0.040 inches above the draw pad 70 for the stage 2 pocket. The die center insertion member 122 for the stage 3 pocket is 0.116 inch (0.295 c).
m), so that the die center punches 38 for these pockets are located 0.056 inches below the die center punches 38 of the stage 2 pockets. Similarly, inserts 120, 121 for pockets 7, 8 of stage 4 are 0.072 inches (0.183 inches).
cm) and the die center insert 122 for these pockets is 0.198 inch (0.503 c
m). As a result, the draw pad 70 for these pockets is located 0.072 inches above the draw pad 70 for the stage 3 pocket, and the die center punch 38 for the stage 4 pocket is , 0.082 inches below the die center punch 38 in the stage 3 pocket.

As shown in FIGS. 5 to 7, for example,
A metal sheet S, such as 0.011 inch (0.028 inch) thick aluminum, is provided between the lower and lower tools in FIG. Due to the downward movement of the outer ram 24 and the upper die 52, the sheet S is cut or blanked between the annular cut edge 78 for the first to stage 4 and the annular blank / draw die 90. An annular blank B is formed continuously. As is apparent from FIG. 5, as a result of the increased thickness of the insertion members 120 and 121, the blank B is continuously clamped to the blank / draw die 90 by the draw pad 70 for the first to the stage 4. That is, it is supported.
6 and 7, as the inner ram 22 and the inner die 32 are moved downward, the die center punch 38 for the first to the stage 4 continuously engages with the blank B, The blank is continuously squeezed into the corresponding cup C. As can be seen from FIG. 7, the increased thickness of the center insert 122 on the die center punch 38 for the first through stage 4 allows the cup for stage 2 to be positioned before the cup for stage 1. The cup C is continuously squeezed in the reverse order, such that the cup C is sufficiently squeezed and the cup C for the stage 4 is sufficiently squeezed before the cup C for the stage 3 is sufficiently squeezed.

FIG. 9 is a partial cross-sectional view of a cup forming tool constructed in accordance with another embodiment of the present invention, similar to the cup forming tool described above with reference to FIGS.
In FIG. 9, the upper die 130 is connected to the outer ram 24 to reciprocate vertically in, for example, a stroke of about 2 inches. A cylindrical bore 132 is provided in the upper die 130 for each pocket or position of the tool.
And the corresponding rising portions 13 formed therein.
4 is slidably supported. This rising portion 134
Is connected to the inner die 32 so as to reciprocate vertically in a stroke of about 5 inches, for example. The lower end of each rising portion 134 supports an annular die center punch 136 attached to the rising portion 134 by an annular hub 138 and a center screw 141. An annular spacer wedge or ring 143 is
6 and the annular shoulder of the rising portion 134. The spacer ring 143 is attached to the rising portion 134 by a series of screws 144 that are circumferentially separated from each other. So that the air flow path 147 receives a compressed air pulse, as described above in connection with the air flow path;
It extends in the rising direction 134 and the hub 138 in the axial direction.

An annular body, that is, a holding member 150 is formed by each rising portion 134 and a corresponding die center punch 136.
Are mounted on the bottom surface of the upper die 130 by a series of springs 153 which are circumferentially separated from each other and each extend in the axial direction, and a set of precision positioning pins 154. The holding member 150 defines therein an annular chamber 158 that receives compressed air via a flow path 159 in the upper die 130. Annular piston 165
Are movably axially supported within the chamber 158, and the piston has a lower portion directly connected to an annular draw pad 168 surrounding the die center punch 136. The draw pad 168 is preferably formed of a material that is harder than the piston 165 and is attached by a pressure-fit connection.

An annular cut edge die 172 surrounds the draw pad 168 and is attached to the annular cut edge retaining member 174 by a pressure compatible connection (pressfit connection). Flat spacer ring 177
Are attached to the cut edge retaining member 174 by a series of circumferentially spaced screw screws 176, and the retaining ring 182 is circumferentially spaced from each other by a series of axially extending screws 183. With the holding member 150
It is attached to. The retaining ring 182 constitutes a seat of the piston 165, and regulates the downward movement of the piston 165. A series of circumferentially spaced screws 18
6 are threaded into the retaining member 150 through holes formed in the cut edge retaining member 174, the spacer ring 177, and the retaining ring 182 so as to be aligned with each other. As is clear from FIG.
6, the cutting edge die 172 and the die holding member 174 can be easily removed, and by removing the screw 183, the holding ring and
The piston 165 to which the draw pad 168 is attached can be easily removed. The holding member 150 can be removed by removing the screw 153.

Since the components of the tool mounted on the lower die 18 are substantially the same as those of the lower tool described above with reference to FIG. 3, the same reference numerals are used for various components and parts. Have been. As is clear from the comparison between the upper tool shown in FIG. 9 and the upper tool shown in FIG.
Although the tool shown in FIG. 9 performs a similar function,
The number of parts is small. The components of the tool shown in FIG. 9 include the screws 141, 186, 18 when the die is retracted.
By removing 3,153, simply the upper die 1
Removed conveniently from 30.

A series of tooling devices as described above and methods of using the same are described, for example, in US Pat. 5,394,
It is practically suitable for the manufacture or molding of metal cups having a bottom with bosses projecting inward or outward, as disclosed in US Pat. As shown in this patent, the upwardly projecting boss is reshaped to form a funnel-shaped cross-sectional annular bottom wall. In accordance with the present invention, tooling teeth for producing such a cup include a composite stage, such as a four stage, as shown in FIG. 1 and described above. Each stage preferably has a plurality of tool sets, each of which is substantially equal at each pocket 26 described above with reference to FIG. 1, each of which is configured as shown in FIG. Accordingly, only one set of copper tools will be described below.

As shown in FIG. 10, the upper tool components connected to the inner rim 22 and the outer rim 24 are substantially the same as the tool components described with reference to FIG. Therefore,
These components have the same reference numerals. However, this die set has a different structure from the lower die 18 described with reference to FIG.
0) includes different lower tool components.

As shown in FIG. 10, the lower die 218
Supports a blank / draw die 220 for each tool station. The die 220 has an inwardly projecting annular tongue 222 defining a corresponding die pocket 26 (FIG. 1). The blank / draw die 220 has a substantial height substantially forming a cylindrical column, and further includes an annular base 224. The annular base 224 is disposed in an opposing bore formed in the lower die 218 and is attached to an annular holding member 226 located here by a positioning pin 227. The blank / draw die 220 includes a set of annular spacers or wedge plates 228,22.
9 and is attached to the holding member by a plurality of screws 231 circumferentially separated from each other.

A laterally extending cup discharge opening or port 233 is formed in the blank / draw die 220 and is connected to a tubular discharge conveyor or duct 236. An air jet tube 238 extends from the pressurized air supply duct 240 via the opposite side of the blank / draw die 220. Also, a set of three strip fingers 242 extend laterally through the blank / draw die 220. Each finger 242 is spring biased inward to the strip position (FIGS. 10 and 15). An annular air chamber 244 is defined in the tool holding member 226 and is provided with an overstroke piston 2.
It is closed by 48 cylindrical rod portions 246.
The piston 248 is vertically movably supported within an air chamber 252 defined by a cylindrical sleeve 254 lining an opposing bore in the lower die 218. The cylindrical stationary hub 256 is
Located at the center of 52, has a bottom flange attached to the lower die 218 by a set of screws 257. The stationary hub 256 is connected to the overstroke piston 248.
The compressed air projects upwardly into a cylindrical bore therein, and compressed air is directed to port 259, flow path 261, flow path 263 in piston rod 246, and discharge port 264 for purposes described below. Supplied.

The substantially cylindrical bottom panel punch 265 has one
It is attached to the overstroke piston rod 246 by two center screws 267. An annular spacer plate 269 is attached to the annular shoulder of the panel punch 265 by one set of screws 271. A lower pressure sleeve 275 surrounds the panel punch 265, which is vertically movably supported within the lower portion 224 of the blank / draw die 220. The pressure sleeve 275 includes a lower annular head or piston 2 slidably supported in the air chamber 244.
78. One set of elastic O-ring seals includes pistons 248 and 278, an annular holding member 226, and a sleeve 2
54 as well as in corresponding grooves of the rod 256, so that the annular air chambers 244, 252
A fluid-tight seal is formed to confine compressed air therein.

As shown in FIG. 11, the set of tool components described with reference to FIG. 10 for each die station or pocket effectively produces a drawn metal cup C1 from a substantially circular metal sheet blank B1. I do. Each cup C1 has a cylindrical side wall and a bottom wall with a substantially cylindrical boss 285 protruding inward or outward.
As described above, boss 285 is disclosed in U.S. Pat. 5,3
94,727, used in redrawing and reshaping operations. 8 form a bottom end configuration in a beverage container. During each stroke of the double acting press, cup C1
Is formed at each die station from the corresponding blank B1. FIGS. 12 to 17 show the tool components at the various stations and the various cups corresponding to the condition as the inner and outer rams of the dual-acting press are moved up and down. As can be seen from FIGS. 14 and 15, the boss 285 pushes each cup C toward the bottom stroke of the inner ram 22 and the connected die center punch 136.
1 is formed. As the die center punch 136 presses the bottom wall of the cup C1 against the upper end of the annular pressure sleeve 275 (FIG. 14), the panel punch 26
5 is a hub portion (annular hub) 1 of the die center punch 136.
The interior of the bottom wall is continuously pressed upward into a circular cavity 288 in 38 (FIG. 15) to form a boss 285.
Preferably, the air supplied to chamber 244 (FIG. 1)
0) is in the 30 to 40 psi pressure range, while the pressure supplied to the overstroke chamber 252 is maintained at about 400 psi. Thus, panel punch 265 (FIG. 15) moves down only one of a few thousand inches during the overstroke after boss 288 is formed in cavity 288 of die center punch hub 138.

As the inner ram 22 moves upward after the lower limit of the press stroke (FIG. 16), the pressure sleeve 275
And the air supply flow path 259,
263 as well as the compressed air supplied beneath the cup via port 264, the
6 and move upward. As cup C1 moves upward to the position shown in FIGS. 16 and 17, the strip fingers 242 engage the upper edge of the cup and slide the cup against the die center punch 136. Then, as soon as the die center punch 136 moves above the cup C1 and the cup is slid, the tube 238 as shown in FIG.
The air jet from blows out the cup via port 233 into the air carrying tube or duct 236. Thus, each cub is ejected laterally from the press below the level of the sheet metal blank resting on the stock plate 110.

Seam washers, ie plates 143, 182, 229, 269, for the various four stages
By precisely selecting the thickness of each blank,
1 is a cut edge 172 and a corresponding blank /
Cut or punched between the draw die 220 and the draw pad 168 and the corresponding blank /
It is supported between the draw dies 220 and subsequently drawn (squeezed) by a die center punch 136 that moves into the corresponding blank / draw die 220. Further, subsequently, the boss 285 of the cup C1 is molded, that is, drawn in four stages.

From the drawings and the above description, it is clear that a mechanical press for forming a cup with a tool constructed in accordance with the present invention has the desired aspects and effects. One important aspect is that stage 1 to stage 4 draw pad 70 or 168 and blank / draw die 90
Or blanks B or B continuously between 220 and
By holding or gripping one, the dynamic load on the outer ram 24 is substantially reduced. For example, 25
A compression load of 98 tonnes on the outer ram of a 150 ton press, operated at 0 spm and having a tool with eight pockets, translates to a compression load of 48 tonnes when using a tool constructed in accordance with the present invention. Is reduced. This means
Shows a reduction of the compression load on the outer ram of more than 50%, thus making it possible to substantially increase the speed of the press without overloading the press.

Further, by combining the continuous operation of the tool components shown in FIG. 10 at each station, the cup C1 having the reshaped boss 285 can
-Can be manufactured at high speed using existing presses with an outer ram having an inch stroke and an inner ram having a 5 inch stroke. Copper presses known in the art can be re-fitted with a continuous stage tool as shown in FIG. As a result, a 150 ton cup press can be run at 250 tons per minute without overloading the inner and outer rams of the press.

While the continuous holding of the blank B or B1 greatly reduces the load on the press, the continuous blanking of the sheet S to form a flat circular blank B or B1 also requires a double-acting press. It also reduces the compression load on the outer ram. Further, continuously squeezing the blank B or B1 to the cup C or C1 requires the inner ram 2
2 is further reduced. Obviously, the continuous use of the tool also reduces the maximum tensile load on the components of the press when the ram changes its direction at the bottom of the stroke.

The present invention is described as using inserts (seams) 120, 121, 122 or seams 143, 182, 229, 269 to perform a series of blanking, holding, and drawing operations with existing copper tools. However, the new copper tool is
It is self-evident that it can be configured with dimensions that eliminate the need for 0, 121, 122. In addition, the table of FIG. 8 shows the process sequence for a tool with 14 cups or pockets, but the process differences for the first through stage 4 include the number of stages, the number of pockets, It can vary according to the type of tool as well as the type of mechanical press. The “cup-shaped articles” used herein include various articles formed by drawing a metal, each of which has a cylindrical wall extending upward and a bottom wall integrated with the cylindrical wall.

Although the described method and apparatus form are preferred embodiments of the present invention, they are not limited only to the described method and apparatus form, but the scope and spirit as defined in the claims. Various changes are possible without departing from.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a lower cup forming tool constructed according to the present invention with a stock plate removed.

FIG. 2 is a partial cross-sectional view of the upper and lower cup forming tools of a double-acting press, taken along line 2-2 of FIG. 1 and showing the multi-stage of the tool.

FIG. 3 is an enlarged partial cross-sectional view of one of the tool stages shown in FIG. 2;

FIG. 4 is an exploded view showing a set of upper tool elements shown in FIG. 3;

FIG. 5 shows a series of blanking according to the present invention;
FIG. 4 is an enlarged sectional view of the tool element shown in FIGS. 2 and 3 in a first step, for explaining a holding and drawing operation.

FIG. 6 is an enlarged sectional view of the tool element shown in FIGS. 2 and 3 in a step following FIG. 5;

FIG. 7 is an enlarged sectional view of the tool element shown in FIGS. 2 and 3 in a step following FIG. 6;

FIG. 8 is a table diagram showing the relationship between the multi-stage and stepped tool components shown in FIG. 2 and FIGS. 5 to 7;

FIG. 9 is a view similar to FIG. 3, showing a modification of the tool stage.

FIG. 10 is a view similar to FIGS. 3 and 9, showing an embodiment of another tool of the present invention.

FIG. 11 is a view for explaining withdrawal of a cup provided with a boss formed in advance at the bottom using the tool shown in FIG. 10;

FIG. 12 is a partial cross-sectional view of the components of the tool of FIG. 10 showing one step for forming the cup shown in FIG. 11;

FIG. 13 is a partial cross-sectional view of components of the tool of FIG. 10 in a step following that of FIG. 12;

FIG. 14 is a partial cross-sectional view of components of the tool of FIG. 10 in a step following FIG. 13;

FIG. 15 is a partial cross-sectional view of components of the tool of FIG. 10 in a step following FIG. 14;

FIG. 16 is a partial cross-sectional view of components of the tool of FIG. 10 in a step following that of FIG. 15;

FIG. 17 is a partial cross-sectional view of components of the tool of FIG. 10 in a step following that of FIG. 16;

FIG. 18 is a partial cross-sectional view of components of the tool of FIG. 10 in a step following that of FIG. 17;

[Explanation of symbols]

130: Upper die, 136: Die center punch, 138
… Die center punch hub, 218… Lower die, 220…
Blank / draw die, 246 ... piston rod, 26
5 Panel punch, 275 Pressure sleeve, 278 Piston, 285 Boss, C1 Cup, B1 Blank

Claims (10)

[Claims] 1. A method for forming a series of cups from a strip of metal sheet with each stroke of a double-acting mechanical press, the press being supported for reciprocating movement and supporting a tool. The tool has a series of horizontally spaced, substantially identical cup-forming stations, each station having an annular draw pad, and an annular blank / draw die facing the draw pad at each station. An annular cut edge die surrounding the draw pad at each station, a die center punch in the draw pad defining a cavity at each station, and a pressure sleeve surrounding the corresponding bottom panel punch facing the die center punch at each station The method comprises the steps of: forming a series of disc-shaped blanks at the station; Cutting the die between the annular cut edge die and the corresponding blank / draw die, and holding a metal blank between the annular draw pad and the corresponding annular blank / draw die at a station. And a step of drawing the blank into the cup. Subsequently, a holding force is applied to the metal blank between the annular draw pad and the corresponding annular blank / draw die, and the pressing of the press is performed. Reducing the mechanical load on the press during each stroke, and moving the bottom panel punch into the cavity in the corresponding die center punch by moving the corresponding bottom panel punch into the bottom of each cup at each station. Forming a boss protruding inward in the cup. 2. The method of claim 1 wherein each bottom panel punch is moved into a cavity in a corresponding die center punch near the bottom of the inner ram stroke. 3. At each station, the bottom panel punch is subsequently moved into a cavity in a corresponding die center punch during each press stroke to further reduce the load on the press. the method of. 4. The method of claim 1, wherein at each station, the die center punch subsequently draws a metal blank into the cup during each stroke of the press to further reduce the load on the press. 5. The cutting edge die and the corresponding blank / draw die at each station then cut the strip at each station to further reduce the load on the press during each stroke of the press. The method of claim 1. 6. Inserting a slightly different thickness seam member into the tool to change the spacing between the die center punch and the corresponding blank / draw die at each station to subsequently draw the blank into the cup. The method of claim 1 comprising the step of: 7. A double-acting mechanical press comprising an inner ram and an outer ram supported reciprocally, the ram continuously and simultaneously forming a group of cups from a strip of metal sheet. A tooling device used, said tooling device having a series of horizontally spaced apart, substantially identical cup-forming stations, each station comprising:
An annular draw pad connected to move with the outer ram, an annular blank / draw die facing the draw pad at each of the stations, and each surrounds each draw pad and is connected to move with the outer ram. Includes an annular cut edge die, a die center punch within each draw pad and connected for movement with the inner ram, and a pressure sleeve facing the die center punch at each station and surrounding the bottom panel punch. The annular cutting edge die and the corresponding blank / draw die, comprising cup forming tool components, form a series of substantially annular disk-shaped blanks at each stroke of the outer ram at the respective station. Cooperate, and also
At each of the stations, the corresponding blank / draw die and the opposing draw pad are opposed surfaces cooperating to hold a metal sheet between the draw pad and the blank / draw die with each stroke of the outer ram. At each of the stations, the die center punch and the corresponding blank / draw die are interposed between the inner ram for each stroke of the inner ram to continuously draw a blank into the cup. It has opposing surfaces of slightly different spacing to reduce positive compressive and tensile loads during each stroke of the inner ram, and that at each of the stations the bottom panel punch has a corresponding die center punch. Forming an inwardly projecting boss in the bottom of each cup in cooperation with the cavity inside Fixture device. 8. The blank / draw die and the opposing draw pad are used to hold a metal sheet between the draw pad and the blank / draw die at each station of the outer ram at each stroke. 8. The apparatus of claim 7, wherein each station has opposing surfaces with slightly different spacing between the blank / draw die and the draw pad to further reduce the load on the press during each stroke of the outer ram. . 9. The cut-edge die and blank / draw die have opposing surfaces with slightly different spacing at each stage to continuously form a series of planks on each stroke of the outer ram. Item 7. The apparatus according to Item 7. 10. The apparatus of claim 7, including a plurality of cup forming stages each having said cup forming station, wherein said cup forming stations of each stage are symmetrically disposed with respect to a center plane of the press. .