EP0921878A1

EP0921878A1 - Production of lid bordering rings without round cuttings

Info

Publication number: EP0921878A1
Application number: EP97929130A
Authority: EP
Inventors: Wolfgang Peter; Hans Hartung
Original assignee: Impress GmbH and Co OHG; Impress Metal Packaging GmbH and Co OHG
Current assignee: Trivium Packaging Germany GmbH
Priority date: 1996-06-24
Filing date: 1997-06-20
Publication date: 1999-06-16
Anticipated expiration: 2017-06-20
Also published as: EP1029613B1; AU3335397A; NO311412B1; EE03811B1; HUP9903163A3; DK0921878T3; DE19625174A1; CZ293371B6; ATE440687T1; PT921878E; EE9800440A; ES2157076T3; CZ426398A3; WO1997049510A1; PL330919A1; HU223260B1; DE59703067D1; NO986029D0; DE59713015D1; PL186886B1

Abstract

A process is disclosed for forming metallic lid bordering rings (20; 20a, 20b, 20c, 20d, 20e) with an inside opening (21) and a ring-shaped profiled border (20a, 20b, 20c, 20e). A cylindrical blank (10, VR) placed in the centre of several ring-shaped, concentrically joined tool segments (1 to 7) is pushed axially downwards (v0) by a outer tool segment (1) and deformed in a radial direction (v0') over a ring-shaped deflecting lip (5a) of a segment tool (5) located further inward in the radial direction among the concentrically joined tool segments (1 to 7). An upper segment tool (2) is held above the deflecting lip (5a) to define a gap (S) into which the blank (10; VR; HR) radially deformed (v0') inwards is pressed. This avoids the formation of cuttings inside (21) the thus produced lid bordering ring (20).

Description

Cover ring production without disc blanks

The technical field of the invention is the method for forming metallic cover rings, which are required for fitting and flanging onto a container of round or non-round nature. In the prior art, such cover rings are punched out of flat sheet metal, a round blank being formed in the middle, which represents waste; only the cover ring is required for the further production of the container.

In the production of cover rings made of metal, the loss or waste of stamped round blanks is to be avoided;

Reference is made to the claims, in particular 1, 7 and 10, for solving the problem addressed.

The invention is based on the creation of a cylinder ring (ring blank) which has not yet been completely formed and which arises from a can body, produced with a pull-in tool or a telescopic tool. A step tool can also be used to form the ring blank. The can body is formed from a sheet metal cutout in a round and non-round design. By separating (at T) the actual can, the ring blank with the "outer ring dimension" of the cover ring, which is essentially cylindrical or oval (non-circular), has only a small inwardly projecting ring web.

In the sense of the description, a ring blank is to be understood as meaning cylinder segments which are not necessarily circular, but which have a wall height which clearly extends in the axial direction. In the sense of the description according to the invention, a cylinder is also understood to be a non-round cylinder which is oval, with the wall remaining constant in the axial direction.

Such a "cylinder segment" is separated from a not yet fully formed can body, the separation taking place shortly until clearly before the end of the last reduction process (claim 7), in particular between 80% and 95% of the drawing process, if and insofar as the required amount of material remains Cylinder segment corresponds to the amount of material that is provided for the formation of the cover ring. The shape of the cutting line T follows the shape of the ring blank. The cylinder segment is brought into a compilation of several ring-shaped tool segments and moved axially downward to form it via a deflection cliff in a radial direction, where it becomes a radially inwardly deformed and radially extending cover ring. The deflection via the deflecting cliff takes place in such a way that the downward / inward deformed cylinder segment is pressed into a gap which is defined by an upper and an underlying tool segment.

The forming process transforms the cylindrical blank (in a circular to oval base shape) into a flat ring blank (claim 6), which additionally experiences an erected ring wall with an inner roll in an upward gear of another ring stamp.

A cylindrical recess (claim 10) is adapted to the basic shape of the cylindrical blank, it can also have an oval basic shape, but with an axially clear extension to accommodate the cylindrical blank and move it downwards. The radial extent of the recess is adapted to the thickness of the cylinder segment to be formed.

The invention (s) are explained and supplemented below using several exemplary embodiments.

Figure 1 illustrates a first can in section, from which a ring can be separated.

FIG. 2 illustrates an almost finished can which was created in the pulling process or in the pulling process, in which the pulling or pulling process was interrupted shortly before the end in order to obtain an upper cylindrical ring with a larger diameter. Figure 3 illustrates the separation at the ring dividing line T, with a residual

Body 30 and a cylindrical cover ring blank 40 is formed. Figure 4 illustrates the finished cover ring with a horizontal

Ring flange 20c of an inner curl 20e and an outer edge area with an annular hook 20a for attachment to a fold. The inside of the cover ring is open, which is illustrated by the opening 21 which can be seen in section. 5a, 5b, 5c, 5d,

Figure 5e illustrate various positions of a single stage

Tool. Between the upper punches 1 to 4 and the lower punches 5 to 7, which change during the operation of the concentric tool assembly, the geometry of the first cylindrical blank 10 changes into a cover ring subsequently formed according to FIG. 4 in FIG. 5e. FIG. 6a, FIG. 6b,

FIG. 6c illustrate a first tool of a multi-stage tool, in which the cover ring is first formed from a cylindrical shape in FIG. 6a into a horizontal shape with a wall 13 set up vertically on the inside according to FIG. 6c. FIG. 7 illustrates the second tool of the step tool, in which the cover ring 100 which is being created is trimmed on the inside. Figure 8,

Figure 8a illustrate the third stage of the step tool, in which the cover ring receives its inner curl 20e (here 15). With regard to FIG. 1 or 2, it should be noted that the pulling or pulling process is stopped shortly before its end (approximately 80% to 95% before the end of the last reducing process) in order not to retract the diameter of the upper edge 40a of the fuselage to 2xr ₁ . As a result, the edge region 40a remains as a blank cover ring VR when it is severed at T (dividing line). The dismantled fuselage 30/40 in the remaining fuselage 30 and cover ring blank 40 is illustrated in FIG. The dividing line T, which is shown both in FIG. 1 and in FIG. 2, corresponds to the circular or oval basic shape of the container 30. In FIG. 1, the separation takes place from above in the case of a container formed in the pull-in pull, the pull-in not yet completely ending has been conducted. In FIG. 2, the separation is carried out from above or below at the dividing line T, the last reduction process, for example in the case of production with a telescopic tool, or the last step of a step tool not being completed, so that the cylindrical blank is above the fuselage 30 remains while he remained next to the fuselage in Figure 1, but in both versions with a larger diameter than the finished reduced fuselage.

The further processing of the ring blank 3 into a finished cover ring 4 can be carried out either by a single-stage tool 5 or by a multi-stage tool. The first stage can be seen from FIGS. 6a, 6b, 6c, the second stage from FIG. 7, the third stage from FIGS. 8a and 8b.

The transfer between the stations takes place e.g. B. via a gripper transport. The function and mode of operation is explained and supplemented using the following examples of tool designs.

Figures 5a to 5e show the operation of the single-stage tool. The ring VR separated from the can is placed mechanically or by hand on part 5 from FIG. 5a. The tool parts 2, 3 and 4 are then moved into the ring by the machine stroke and form a gap S of 0.8 x sheet thickness to the parts 5, 6 and 7. The parts remain in this position until the shoulder 1 a of the

Stamp 1 has inserted the sheet metal ring in the axial further decline of part 1 so far radially v _n 'that the sheet metal ring VR.10 has reached the horizontal position in FIG. 5b.

The sheet is clamped in this position between the tool parts 2 on the one hand and 5 on the other hand. Part 1 remains in this position by placing it on a stop. Parts 3 and 4 are subjected to a hold-down force acting on parts 6 and 7. v denotes directions of movement (based on speeds), where the "deleted" quantities ^ Q y ^ 'y ^ ^rad ' ^a ' ^e components of the sheet and the "not deleted" quantities denote axial movements of the tool.

Due to the further decline v ₁ of part 2 together with part 5, the step 20b in the cover ring and the cover ring depth according to FIG. 5c is reached in the sheet metal ring. Sheet material is drawn in the v- _j 'direction.

By taking part 3 through part 2 and through the counter-holding and clamping function of parts 5 and 6, a hold-down function takes place

Rolling ring 4 and the pulling process then taking place over the punch 7 a list of the inner edge of the cover ring. In this stamp lowered position, the cover ring has the shape according to FIG. 5d. The plunger is then lifted upwards with the upper part of the tool and parts 2 and 3, while the rolling ring 4 remains in its position.

In FIG. 5d, sheet metal is pulled in the direction ^ 2 and the ring wall 20d is set up.

The parts 2 and 3 following parts 5 and 6 press the set-up 20d of the cover ring into the rolling groove 4a of the rolling ring 4. Since the forces of parts 5 and 6 and of the counteracting rolling ring 4 are greater than the deformation resistance of the Sheet metal material, an inner roller 20e of the cover ring is formed in the roll groove 4a of the roll ring 4 by the ripening of the cover ring assembly. After completion of the stroke, the cover ring has taken the form of Figure 5e. The part 3 is then relieved of force, the parts 1, 2 and 5 move back into the starting position. When the tool is moved apart, the ring shown in FIG. 4 is ejected.

In the decline of the stamp rings 2, 3 and 5, 6, the set-up 20d located on the inside of the cover ring is thus formed.

FIGS. 6a, 6b, 6c, 7 and 8.8a represent the manufacture of the cover ring in three or in several possible operations. The manufacture can take place both on individual presses and on step or transfer presses.

In FIG. 6a, the ring (FIG. 3, top) separated from the can (according to FIG. 1 or FIG. 2) is fed to the tool station (FIG. 6a) and positioned on part 5. During the decline with the upper part of the tool, part 2 is initially centered on the inner region 40b of the sheet metal ring 100. When placed on a stop, part 2 and part 5 (without sheet metal) form a gap of 0.8x sheet thickness. In the further tool descent, part 1 passes over the outer region 40a of the sheet metal ring 100 and pushes the ring with the shoulder 10 through the part 5, which is subjected to a holding-down force and which forms a gap S <sheet thickness with part 2 up to the inner diameter of the finished cover ring. The sheet metal ring 100 then has the shape of FIG. 6b. In this position, the punch 8 simultaneously reaches its end position and, with its cutting edge 12, squeezes the sheet metal into the recess provided for this to approximately a depth of 0.5 × sheet thickness over the cutting edge 11 of part 7. By

Placing part 1 on the paragraph 5x of part 5, part 5 is pressed down. Part 2 follows part 5 with the hold-down force applied. Because the sheet metal ring is clamped in the area of the cutting edges 11, 12, the sliding process changes into a drawing process during the continued stroke. As a result, the set-up 13 for the following inner roll of the sheet metal ring 100 according to FIG.

With regard to FIG. 6c, it should be noted that the axially erected wall 13 (cf. 20d in FIG. 5d) is produced by pulling, which has advantages over the thrust of FIG. 5c if the radii become larger.

In FIG. 7, the preformed sheet metal ring 100 is transported into the trimming station and placed on the lifting ring 6 '. When the upper part of the tool falls, the shaped ring 2 and the holding-down ring 9a bring the preformed sheet metal ring 100 into position so that the subsequent punch 8 'can cut off the inner edge 100r via the cutting punch 9b. This eliminates material-specific anisotropies from the push-pull process. An inner cutting edge 100k remains. The separated ring 100r is removed by the lower tool.

The trimmed sheet metal ring according to FIG. 7 is then transported to the finishing station of FIG. 8 and placed on the parts 5 'and 6' which are flush with the top. The parts 2 'and 3' coming from top to bottom during the press stroke are also flush when viewed from below and center with the inside dimension of part 3 'over the outside dimension of the set-up 13 of the bending ring 100. If the set-up 13 inside via part 7 outside is fully centered, part 6 "remains on a stop, part 3 'springs back on the sheet metal ring 100 and part 6' during the further tool descent. Part 5 'then forms the edge of the sheet metal ring 14 to the lower one via the sheet metal holder 2' Dead point of the press. In the upward stroke, that between the parts 5 'and 6' (FIG. pinched sheet metal ring pressed upwards, so that the assembly 13 is pressed into the rolling groove 4a of the standing part 4. This process creates the inner roller 15 of the sheet metal ring 14. To eject the sheet metal ring from the tool, part 3 'is relieved of force after the completion of this process.

This multi-stage production is particularly suitable for cover rings with a wider radial flange 20c.

Claims

Expectations:

1. A method for forming metallic cover rings (20; 20a, 20b, 20c, 20d, 20e) with an open interior (21) and an annular profiled edge (20a, 20b, 20c, 20e), in which

(a) a cylindrical blank (10.VR), in particular a cylinder segment (40; 40a, 40b) separated from a can body, in a concentric arrangement of several ring-shaped tool segments (1 to 7) from an outer (1) of the tool segments (1 to 7) is displaced axially downward (v _n ) in order to be deformed in a radial direction (VQ ') via an annular deflecting cliff (5a) of a radially inner tool segment (5) of the concentric assembly of a plurality of tool segments (1 to 7);

(b) an upper tool segment (2) is held above the deflection tip (5a) in order to define a gap (S) into which the radially inwardly deformed one

(v ₀ ') blank (10; VR; HR) is pressed.

2. The method according to claim 1, wherein the gap (S) in the empty state is thinner, in particular significantly thinner, than the sheet thickness of the cylinder segment (VR; 10).

3. The method according to any one of the claims mentioned, wherein the outer tool segment (1) has an annular shoulder (1a) with which the upper edge of the cylindrical blank used (VR) is gripped and moved downward (VQ).

4. The method according to claim 3, wherein the shoulder (1a) is the upper edge of a circumferential ring recess (1b) in the outer tool segment (1), which corresponds in its radial dimension approximately to the thickness of the unformed cylindrical blank (VR).

5. The method according to any one of the preceding claims, wherein the downward movement of the outer tool segment (1) is terminated when the shoulder (1a) reaches the deflecting cliff (5a) (Figure 5b). 6. Forming method according to one of the preceding claims, in which in the decline of several tool ring punches (1 to 7) a thin-walled cylindrical blank (VR; 40) in a flat ring blank (20a to 20d) with an inner ring wall (20d) implemented and in the upward gear of several ring stamps (2,3,5,

6) the erected ring wall (20d) in one

Inner roll (20e) is formed.

7. A method for producing a blank in a substantially cylindrical shape (40; 40a, 40b) for the aforementioned method, in which (a) a cup-shaped in a deep-drawing process or an everting process

Lower part of a container is reduced from a first diameter (2 ^) to a smaller diameter (2r ^); (b) the reduction process according to feature (a) is terminated shortly before the end in order to leave a cylindrical strip (40a) at the upper end of the almost completely formed lower part of the container, which after extensive detachment along a circumferential cutting line (T) cylindrical blank (VR, 10) from which a substantially flat cover ring (20a to 20e) can be formed.

8. The method according to any one of the preceding claims, wherein the cylindrical

Blank (VR) has a residual radial web (40b) which, after being inserted into the concentric assembly of tool segments (1 to 7), already lies radially inside the deflection cliff (5a).

9. The method according to any one of the preceding claims, in which the radially inwardly (VQ ') in the gap (S) pressed sheet material of the cylinder shape blank (40) is pushed over more than two concentric tool segments (2,3; 5,6) .

10. Device for the previously claimed method, in which

(a) a plurality of annular tool segments (1 to 7) are provided which are axially movable relative to one another;

(b) one of the plurality of tool segments as the outer push segment (1) has a cylindrical recess (1b) formed on its inner surface, which is adapted to the thickness (d) of a thin metal cylinder plate (VR) to be formed;

(c) an annular receiving surface (5b) is formed on a tool segment which is arranged further inwards and is designed as a deflection segment (5) and has an annular inlet lip (5a) facing the recess (10b) of the thrust segment (1).

11. The device according to claim 10, wherein the annular receiving surface (5b) is slightly curved in the axial direction (100), at least in 5 an outer region (5b ').

12. Device according to one of the device claims mentioned, in which a further inward - in particular third place, calculated from the outer thrust segment (1) - arranged rolling tool segment (4) has a circumferential o roll groove (4a) into which from below axially set up sheet metal wall (20d) can be pushed in, where it rolls up on the inside edge (20e, 13).