FI72062C - Method and apparatus for forming an end portion of a cylindrical met allbur mantle. - Google Patents

Description

ΓΒ1 m ANNOUNCEMENT n 9 n s 0 JfSi® ™ ^ UTLÄGGNINGSSKRIFT / 41 U O Z

C Pat excreted granted (45) Patent r: a .2 Feet 13 C <i l'JC7 (51) Kv.ik // lnt.CI. * B 21 D 51/26, 19/00 (21) Patent application - Patentansökning 762516 (22) Application date - Ansökningsdag 01.09.76 (Fl) (23) Starting date - Giltighetsdag 01 .09 * 76 (41) Has become public - Blivit offentlig 06.03.77

National Board of Patents and Registration Date of publication and publication. _ 31 12 86

Patent and registration authorities V 'Ansökan utlagd och utl.skriften publicerad (86) Kv. application - Int. ansökan (32) (33) (31) Privilege claimed — Begärd priority 05.09.75 Eng 1 anti-England (GB) 36596/75 (71) Metal Box Public Limited Company, Queens House, Forbury Road, Reading, Berkshire, Engl anti -Eng 1 and (GB) (72) Jozef Tadeus Franek, Chorleywood, Hertfordshire,

Peter Henry Doncaster, Harrow, Middlesex, England-England (GB) (7 * 0 Oy Kolster Ab (5 * 0 Method and apparatus for forming the end portion of a cylindrical metal can shell - Förfarande och anordning för moldning av en änddel i en cylindrisk metal 1burkmantel This invention relates to a method as defined in the preamble of claim 1 and an apparatus as defined in the preamble of claim 3 for forming the end portion of a cylindrical metal can jacket.

The purpose of the circumferential flange is usually to form a part to which the end is attached after filling of the can, which attachment is made by changing the end flange of the can body together with the circumferential flange of the can end to form a double seam. Thanks to the neck, the flange and also the top of the can can have a smaller diameter than if there were no neck; the radial depth of the neck is usually such that the outer diameter of the double seam is not larger than the diameter of the cylindrical side wall. Some types of metal containers, such as those with resealable lids that are "levered", have a portion attached to the end of the can body, usually a ring to which the lid engages.

2 72062 The neck of the head may have another function, namely to form a means to which the supporting member can be easily attached; such load-bearing members are designed to contain a plurality of containers and may be, for example, cardboard or a flexible plastic material. Such a support member connecting the neck of the container in question usually comprises a horizontal partition with a plurality of holes, the circumference of each hole being connected under the double seam of the end of said container, supporting the container in whole or in part in this way. When the container body is provided with a neck, the neck can be shaped to provide some support and / or retention for the carrier partition around its hole and to enhance locking of the container to the partition until the user wishes to pull the container out of the carrier.

Various methods have been proposed for forming the neck and flange of the head in a one-piece can body. Some methods involve casting the neck and / or flange using circumferentially extending molds. Other methods include rolling or compression turning the neck and / or flange using an external compression roller in conjunction with an inner portion within the can body. In these latter methods, which are known to us, the can body is rigidly supported on an internal mandrel or the like; the inner part may be a pressure roller or a spindle supporting the can body. In one such method, the neck and flange are formed simultaneously in a can body supported internally and rigidly by a mandrel or chuck of the expandable type, the profile of the neck and flange being formed by external pressure rollers cooperating with this mandrel.

In another method, the can body is supported internally by an anvil and end-to-end by a compression guide, wherein the neck and flange are formed by a profiled, external compression roller that forms a groove in the can body formed by the guide and anvil, the roll being moved axially relative to the can body.

In all these methods proposed above, the final profile of the neck and flange is determined by the profiles of the tool parts used to shape them, since the tool elements (i.e. molds, press rollers, mandrels, anvils, etc.) are provided with machining surfaces of the desired shape on the neck and / or flange. , and the metal shape of the can body is changed to match these profiles. If a separate shape is desired, the tools must therefore be changed to obtain working elements with a different profile.

With such a method using an expandable mandrel, it is possible to produce the main flanges and neck parts reliably and economically also in can bodies made of currently popular, thinner and harder metals, in particular a double-thin plate, which is usually a tinned steel plate, but which can be e.g. melted steel or black-steel plate, which is treated appropriately but which does not necessarily have to be coated with another metal. The present invention is also particularly suitable for use with these thinner and harder materials.

The invention thus relates to a method of forming an end portion of a cylindrical metal can casing having a radially outwardly directed end flange at its open end having a circumferentially reduced neck portion immediately joining said end flange radially extending to the end edge of the canister. around a first tool coaxially arranged inside the can shell, wherein the upper surface of the end flange is axially supported by the abutment portion, the can shell and the second tool forming the pressure roller are rotatably relative to each other about the axis of the can shell, the second tool being arranged outside the can shell , in which the tools have a constant axial position relative to each other and a continuous axial compressive force is applied to the can shell by a stop part and a lifting plate resting on the bottom of the can, and at the other, the tool forming the pressure roller applies an inward radial force to the can shell near the end flange of the can.

The method is characterized in that the end edge of the first tool is axially closer to the abutment portion 4,72062 inside the sheath than the abutment side edge of the second tool, and in the method the tool is moved radially inwardly past the end edge of the first tool and is rotated about the can axis and / or the second tool in said manner to cause rotational movement between the can and the second tool so that the entire axial top of the can shell bends progressively from the end flange to the second tool radially inwardly into the gap between the first and second tools and behind it in the free space below the end face of the first tool as a first point of support. around the end edge of the tool, whereby the casing of the can simultaneously shortens and forms an inwardly contracted neck portion as an extension of the flange, the profile of which is determined by the relative movements of the abutment part, the lifting plate formed by the support member and the tool end edges.

It is obvious that one of the basic features of the methods of the invention described above is that, unlike the previously proposed methods, neither the profile nor the shape of the neck nor the flange depends on the use of one or more tool surfaces formed with the required profile, since the present invention does not need to be done by introducing the workpiece material, e.g. in a mold, by casting, rolling or pressing into close contact and thus not in an adaptive relationship with such such profiled tool surface or surfaces, but instead in a free space. However, within the scope of the invention, this does not exclude the possibility that some part of the profile is consistent with the profile of the tool edge. However, in the present invention, the material is generally deformed to a shape determined in part by the properties of the axial shortening force and the radial force, and therefore the properties of the various relative movements applied to the workpiece, i.e. the neck and main flange in the workpiece. a metal material having a predetermined thickness, sidewall length, and diameter is predetermined by appropriately selecting a speed variation and relative timing for radial movement between the second tool edge and the workpiece relative to the axial movement between the workpiece and the first and second tool edges.

It is obvious that in the method according to the invention, at any point in the process, contact is made at only three points between the workpiece head and the tool accessory used to form the neck and the flange; i. at the end edge to form a radial stop for the edge and to guide it in its axial movement; at one point on the inner surface of the head by means of the first tool edge; and at one point on the outer surface of the head by means of a second tool edge. It follows that by changing the characteristics of the relative movements of a given workpiece, the shape or profile to be given to the neck and the flange can be arbitrarily changed. In practice, many different such shapes can be made without having to modify the tool parts, as would be the case when the required profile is dependent on tool parts with certain profiles.

The first tool edge is preferably kept stationary and the second is moved radially relative to the workpiece, the workpiece being moved axially relative to the first and second tool edges in such a direction that the axial distance between the latter and the end edge of the workpiece is reduced to zero.

According to the invention, there is also provided an apparatus for forming an end portion of a cylindrical metal can shell having a radially outwardly extending end flange at its open end, a reduced diameter neck portion immediately joining said end flange extending radially to the end edge, the device having a stop portion, to the upper surface of the end flange, a base support member axially compressed coaxially at the opposite end of the can shell, the abutment portion and the support member having a common major axis having a circular cylindrical first tool coaxial with the abutment portion and having an end edge coaxially on the outside of the can , a second tool forming a press roller, arranged radially laterally from the main axis adjacent to the coaxial abutment portion, and having an end edge for applying an inwardly directed radial force to the can, or adapted to move radially with respect to the major axis, and having tools having a constant axial position relative to each other, and wherein the abutment member and support member are adapted to move axially relative to each other to keep the can shell under constant axial compression while simultaneously shortening and shortening the canister sidewall .

the fold is characterized in that the end edge of the first tool is axially closer to the abutment side than the abutment side edge of the second tool, and that the abutment portion, the base support members and the can shell and the second outer tool are arranged in a rotational motion about a major axis simultaneously with the inwardly acting radial force generated at the circumferential edge of the second tool, and with the axial movements performed by the support member with the can shell and the abutment portion with respect to the first and second tools.

The stop part preferably consists of a round stop ring. It is also preferred that the stop ring has an annular claw on the end surface closest to the support member, on which the end edge of the can flange rests.

In addition, the abutment member and the support member are axially movable with respect to the first tool, and the end edge of the first tool is in a fixed radial plane.

Various embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a schematic vertical sectional view showing a part of a can body together with parts of a device in a simple embodiment of the invention; Figures 2-6 respectively show five steps in the formation of the neck portion and the peripheral end flange of the can body, and 7 72002 schematically show an example of a method according to the invention; and Figures 7-10 show fragmentary vertical sectional views showing four examples of neck portions and end flanges that can be formed by the method of the invention.

According to Figure 1, a device for forming a peripheral flange 10 and a flange portion 11 in a can body 12 includes a main support means (described below) coaxially supporting therewith and in axial compression a hollow metal workpiece 13 which is a cylindrical metal can body. The latter is one comprising a thin, cylindrical, seamless side wall 14 with an end 15 (shown in dashed lines); the end 15 has an end edge 16 delimiting the open end 17 of the workpiece. The workpiece 13 includes in one piece a bottom wall (not shown in Figure 1) which may have any known shape, such as an inverted dome shape, part of which is shown in Figure 2. In this example, 14 open or upper ends are slightly spread at the end 15 to form a small initial flange 19. The workpiece 13 is preferably a double-thinned tinned steel sheet or a chemically treated sheet steel or black steel plate.

The abutment portion is in the form of a stop ring 20 having an annular claw 21 at its lower end supporting the end edge 16 of the flange 10, and a bottom support portion in the form of a lifting plate 22 not shown in Figure 1 but used in the arrangement of Figure 2 to support the workpiece bottom wall 18 from below. The lifting plate 22 and the stop ring 20 are designed to move in a controlled manner in the axial direction of the workpiece 13 independently of each other in the manner shown in the following description with reference to Figs. 2-6.

The device also includes a first tool 24 forming a guide located inside the stop ring 20 and the hollow workpiece 13. In this example, the tool 24 consists of a simple plate with a first peripheral tool edge 25 that is slightly rounded. The shaping member is a tapered roller 26 having a tool edge in the form of a regular, rounded peripheral edge profile 27, and the roll 26 is located at a permanent axial distance 8,72062 from the tool edge 25. The taper roller 26 can rotate about its own axis 28 in a known manner and move radially with each other. . The main shaft 23 is common to the workpiece 13, the stop ring 20 and the lifting plate 22. Said relative movement is effected by a controlled radial movement of the roller 26, as indicated by the arrow 29.

The stop ring 20 and the lifting plate, the workpiece 13 and the tool 24 can rotate together about the shaft 23.

An understanding of the operation of the device will be facilitated by the description associated with Figures 2-5. The workpiece 13 is supported by a lifting plate 22 which lifts it (Fig. 2) until the end edge 16 of the workpiece rests on the nail 21 of the stop ring, as shown in Fig. 3. At this point, the stop ring 20 is in its uppermost position and the workpiece 13 is detached from contact with the tool 24.

The workpiece 13 is now supported coaxially in axial compression by a lifting plate 22 and a stop ring 20; the latter retains the end edge 16 radially. As can be seen, the tool 24 is located inside the workpiece 13 and the latter side walls 14 are located between the tool 24 and the constriction roller 26 outside the workpiece.

As the lift plate 22, stop ring 20, tool 24, and workpiece 13 rotate as a unit (as indicated by arrow 31 in Figure 1), the lift plate 22 and stop ring 20 move downward, as shown by the vertical arrows in Figures 4-6, moving the workpiece 13 downward relative to the tools 24. and 26.

During this axial movement, the constricting roller 26, which rotates continuously about its own axis, is moved radially. The axial (vertical) and radial (horizontal) movements of the workpiece 13 are synchronized so that point 32 (Fig. 3) on the roll edge surface 27 first contacts the side wall 14 of the workpiece 13 exactly where the lower limit 33 (Fig. 6) of the neck portion 11 should be. .

As the vertical downward movement of the workpiece continues, the continuous horizontal movement of the taper roller 26 causes a deformation (Fig. 4) in the metal of the workpiece head 15 in the free space between the edge 27 of the rolling tool and the edge 25 of the first tool.

II

9 7,2062 by co-operation, whereby the edge 25 comes into contact with the inner surface of the workpiece with the contact point 32 located between the edge 27 and the outer surface of the workpiece. The tool edge 25 acts as a fulcrum when the metal is pressed into the free space on the tool roll to form a frustoconical neck profile 24. If the radial movement of the cutting belt 26 is now stopped while the axial movement of the workpiece 13 continues, a cylindrical neck profile 35 (Fig. 5) is formed over the profile 34.

Figure 5 shows the end of the shaping work and the stop ring 20 has reached its lowest position and the entire end 15 of the workpiece 13 is formed as a neck portion 11 and a peripheral end flange 10, the latter upper surface being determined by the position of the inner tool edge 25.

It is apparent from the above deposition that the stop ring 20 not only retains the end edge 16 in the radial direction and applies an axial shortening force to it, but also guides the edge in this axial movement of the still unchanged part of the workpiece (see

36 in Fig. 4) to keep it stable in its original state.

As the lifting plate 22 moves steadily downwards by a distance X during the shaping work, the stop ring 20 moves downwards by a distance Y greater than the distance X. The speed characteristic of the movement of the stop ring 20 is determined by the speed at which the metal is pulled out of it axially and varies according to the desired neck and flange profile. It will be appreciated that this change may be predetermined and may be precisely controlled by any of a number of known methods for controlling tools. In the same way, the predetermined characteristics of the radial movement of the constriction roller 26 can be precisely controlled. It is, of course, possible to give the lifting plate 22 such a characteristic movement that it does not move at a substantially constant speed. By arranging the predetermined speed characteristics for the vertical movements of the lifting plate 22 and the stop ring 20 and the horizontal movements of the roller 26 and synchronizing these movements in a predetermined manner relative to each other, any desired neck and flange paprofile can be achieved.

72062 In this connection, it should be noted that the tool 24, the stop ring 20 and the constriction roller 26 form a group of tools which can be easily mounted as a simple modification on a standard machine of known type for narrowing can bodies or pressing end portions into can bodies. Such a machine includes a lifting plate 22 together with drives for rotating the sealing roller and moving it radially; rotating the inner tool and the lifting plate and moving the lifting plate and the inner tool up and down. Since such machines are well known in the art, there is no need to describe them further here; it is clear that the actuator for moving the inner tool up and down can instead be connected to the stop ring 20, so that a vertical movement of the latter and not of the inner tool 24 is obtained. The interconnection of these different drives to adjust the properties as described above can be performed in any known manner. For example, three synchronized cams can be used, which control the vertical movements of the lifting plate and the stop ring, respectively, and the radial or horizontal movement of the constriction roller, whereby all cams are driven from a constant speed motor. Alternatively, a simple electrical control system, of the numerical, magnetic, tape, or "hole card type", may be used to control the various actuators; these systems have the advantage that they are very easily reprogrammable according to the new profile of the neck and flange.

As stated above, it is clear that the final profile of the neck portion 11 and the end flange 10 is determined by the characteristics of the different relative movements of the tool parts 20, 22, 25, 27 together with the properties of the workpiece material and dimensions. The workpiece does not touch the inner tool 24 except at the tool edge 25.

The shaping of the rounded portion 37 connecting the flange 10 to the cylindrical upper portion 35 of the neck portion 11 is enhanced in this example by using the rounded tool edge 27 of the constriction roller 26.

Figure 6 shows the stop ring 20 returned to its up position and the constriction roller 26 in its disengaged position, with the lifting plate 22 lowering so that the finished can body 12 can be removed.

Il n 72062

Figures 7-10 show only four of the many possible profiles of neck portions and end flanges that can be provided by the described methods and devices. Figure 6 shows a fifth such profile. In the profile shown in Figure 7, the neck portion consists of a cylindrical portion 85 connected to the main portion of the side wall 14 of the can body by a substantially radial portion 86. The outer diameter of the end flange 84 is substantially equal to the side wall 14.

In the profile shown in Figure 8, the end closure portion having a substantially smaller diameter than the side wall 14 can be secured to the side wall 14 by a relatively long, frustoconical neck portion 91 by a peripheral end flange 90.

Figure 9 shows a more conventional profile in which the peripheral end flange 100 is an extension of a neck 101 having a C-shaped cross section.

Finally, Fig. 10 shows an example of a profile in which the neck portion comprises more than one neck 110, 111, these being joined together by a circumferential diaphragm 112.

Claims (6)

A method of forming an end portion of a cylindrical metal can casing, which casing is provided at its open end with a radially outwardly extending end flange extending along the entire circumference of the sheath, a neck portion of reduced diameter, which immediately adheres to said end flange. extending radially all the way to an end edge (16), in which method the jar sheath is supported around a circular cylindrical first tool (24), said tool (24) disposed coaxially within the jar sheath, with a stop portion (20) abutting in the axial direction towards the upper surface of the end flange (19), the jar sheath and a second tool (26) forming a press roller are brought in rotational motion relative to each other around the shaft of the jar sheath, which second tool (26) is arranged outside the jar sheath at a distance from the first tool (24). , which tools (24, 26) have a constant axial position relative to each other, and the jar sheath is subjected to a continuous axial compressive force by the impact member (20) and a The lifting plate (22) supported on the bottom of the can, and by means of the second pressing roller forming tool (26), the can sheath is subjected to an inwardly directed axial force in the vicinity of the end flange (19) of the sheath, characterized in that the end edge (25) of the first tool ( 24) is inside the manifold axially closer to the impact member (20, 78) than the edge of the other tool (26) located on the side of the impact member (26), and that in the method where the end edge (16) of the end end flange is in the impact member (20) supported in the radial direction, the upper part (15) of the jar sheath is measured against the end edge (25) of the first tool (24) by moving the impact member (20) against the second tool (26) at the same time as the second tool (26). ) is moved radially in the net past the end edge (25) of the first tool (24) in its immediate vicinity and the can and / or second tool (26) is rotated in said manner about the can axis to effect a rotational movement between the can and the second tool ( 26) in relation to each other in such a way that the entire axial upper part (15) of the jar sheath within the area between the end flange (19) and the second tool (26) progressively bends radially inwardly into and behind a gap between the first and second tool (24, 26) ) into a free space around the end edge (25) of the first tool (24), the end edge of which acts as a support point below the end surface of the first tool (24), at the same time being shortened and also provided with said inset reduced neck portion which elongation of the flange, wherein the profile of said neck portion is determined by the relative movements of the abutment member (20), the lifting plate (22) formed by a support member, and the end edges of the tool (24,26). Method according to claim 1, characterized in that the end edges (25, 27) of the first and second tools (24, 26) are maintained in stationary radial positions relative to each other at the same time as the jar sheath (13) and the axial stop portion (20). is displaced axially in relation to said radial positions. Apparatus for forming an end portion of a cylindrical metal can casing by a method according to any preceding claim, which casing is provided at its open end with a radially outwardly directed end flange extending along the entire circumference of the casing, a neck portion of reduced diameter, which immediately adjoins said end flange which extends radially all the way to the end edge (16), the device having an abutment portion (20) axially pressed coaxially to the upper surface of the end flange (19), the bottom support member (22) axially pressed coaxially towards the opposite end of the jar sheath, the abutment member (20) and the support member (22) having a common main shaft, a circular cylindrical first tool (24) coaxial with the abutment member (20) and having an end edge (25) coaxially located within the jar sheath , an outer, a press roll forming second tool (26) disposed radially on the side of the main shaft next to the axial stop portion (20) and having an end edge (27) for exposing the jar sheath to an inwardly directed radial force, and which is arranged to move radially in relation to the main shaft, and which tools (24, 26) have a constant axial position relative to each other, and in which device the impact member (20) and the supporting element ( 22) are arranged to move axially relative to one another to maintain the jar sheath (13) under the influence of continuous axial pressing while shortening the side wall (14) of the jar sheath II.