JP4567336B2 - Apparatus and method for expanding and forming can body - Google Patents

Abstract

The widening and shaping device has a mandrel-like shaping tool (1) to go in the can body (5) from one side, and a counter-tool (2), also a shaping tool, to go into it from the other side. The cross-section profiles of the two shaping tools are identical or complementary. The tools have spacing from the mandrel axis (9) at one or both ends, at least in part regions.

Description

[0001]
The present invention is an apparatus for expanding and forming a can body, and includes a mandrel-shaped forming tool that can be introduced from one side into a can body to be expanded, and a corresponding tool. About.
[0002]
The invention further relates to a method for expanding and forming the can body, wherein a mandrel-shaped forming tool is introduced into the can body and moved towards the corresponding tool.
[0003]
Such a device and its use are described in DE 100 40 173 A1. The device has a cylindrical cross-section molding block made of hard, thick, steel or some other harder material, the molding block along most of its height, It has a larger diameter corresponding to the inner diameter of the can already expanded and a conical section in the upper part. Above this conical section, a short section with a reduced diameter is arranged, which corresponds to the inner diameter of the can body to be expanded. The molding block is configured such that it can be applied fitably to the can body to be expanded under pressure or to receive the can body. The forming block further comprises, at its lower end, the tool for forming a flange in the form of a steel disk, the steel disk having on its upper side a ring-shaped groove with a narrow groove cross section. The groove can be reached and engaged during expansion and molding from the lower end of the cylindrical can body. The corresponding tool, according to DE 100 40 173 A1, is used in the upper part of the can to form a flange, which also consists of a steel disc, which is on the lower side facing the forming block And having a ring-shaped groove with a narrow groove-shaped cross section and having a small, ring-shaped and protruding section, which surrounds the inner circumference of the groove. The protruding section is held in conformity with the can body that undergoes the process of expansion and molding by engagement. By introducing the forming block into the pre-made can body, the can body is formed on the outer surface of the forming block, in which the can body diameter is increased and in a single processing step the so-called " A “neck-in” is formed. The above-mentioned grooves on both steel disks slightly expand the end face of the can stock each time. The can body shape thus corresponds to the modification of its outer surface after a complete advancement of the shaped body has taken place. In other words, the can body is cylindrical except for a slight upper range, the neck-in range.
[0004]
Gradually individual cans are required from the stuffing factory to escape from rivals. The method currently used for forming cylindrical cylinders is mechanical expansion or expansion. A suitable tool for this consists of a number of segments arranged in a circle, these segments having the desired shape profile on the outer surface. As the tool is introduced into the welded cylinder and the forming segment is moved radially outward by the internal cone of the tool, the segment expands and forms the cylindrical body. The disadvantages of this method are that the circular cylinder is polygonal, the cylindrical cylinder material is stretched locally and strongly, the material shortening is uneven along the circumference, and the expansion is done to the end of the material. It is not possible. This is because any sufficiently precise flanging no longer occurs.
[0005]
Another method is performed with a hollow matrix to be molded, in which the material is formed. A highly compressed air or water jet is useful as the pressure medium. Of course, such methods are expensive, slow and inflexible.
[0006]
The engraving of the formation can also be carried out by means of a so-called spin-flow shape, which is a roll pressure method, in which no expansion takes place and the diameter of the welding material is reduced at the forming site. This method, however, only gives a simple rotationally symmetric shape.
[0007]
Starting from the background art described above, the object of the present invention is to provide an apparatus and method of the type described at the outset, which is not rotationally symmetric for can body formation where an inexpensive, flexible and quick switchability is desired. It is to be able to be manufactured including molding. The machine parts used for this purpose are as robust as possible, and the deformation is possible up to the end of the material.
[0008]
This problem is solved by an apparatus according to claim 1 or 7 and a method according to claim 9.
[0009]
According to the present invention, the finished material, the can body, is produced with a diameter that is smaller than or the same as the minimum desired diameter of the finished part. Unlike the background art, however, according to the first variant, two mandrel-shaped forming tools are used, which are introduced into the can stock from opposite sides and expand the can stock. It is deformed by opening and forming so that the respective end face of the mandrel-shaped forming tool comes to the final position. The cross-sectional profiles of both mandrel-shaped forming tools have a slight distance from the mandrel longitudinal axis, at least at their ends, within the subranges, rather than the corresponding subranges further away from the mandrel ends. . This can consist of rounds or a combination of both that transition conically or tangentially on the end of the mandrel, but also a cross-sectional profile that is not rounded on the outer side or a combination of both. The maximum diameter of the mandrel end is smaller than, equal to, or slightly larger than the diameter of the can barrel to be expanded. In particular, the cross-sectional shape can be tapered towards the end of the mandrel over at least a partial axial direction. The mandrel end face can be arranged or configured perpendicular to the mandrel axis, oblique to the mandrel axis, corrugated, or any other. In the latter case, a constricted portion in the can material can also be formed, and this constricted portion can be formed obliquely, corrugated or otherwise arbitrarily with respect to the longitudinal axis of the material.
[0010]
The subject of the invention is also a method of using the described forming tool in the form of a mandrel.
[0011]
As already mentioned, the material is welded to the smallest diameter of the shape profile or somewhat smaller, and then on both sides, or in special cases on one side, to the final diameter by the introduction of the forming tool, outside the shape profile. Brought about. The configuration of the mandrel end and mandrel determines the shape profile and the outer geometry. Depending on the desired shape, if the end of the mandrel is somewhat larger or the same as the inner diameter of the welded material, the mandrel end will be lightly rounded in the pre-change step. The mandrel can be automatically introduced.
[0012]
As shown in FIG. 1, two mandrel-shaped forming tools 1 and 2 guided through openings in scrapers 3 and 4 facing each other at intervals are used as forming tools for can stock 5. . Since the end portion of the can material 5 is lightly bent and opened in a conical shape, the end portions of the mandrel of the forming tools 1 and 2 can be easily introduced. The open blank 5 is arranged between the scrapers 3 and 4 in a manner known from the background art by means of conveying means (not shown) and at the same time with respect to the tool longitudinal axis 6 which is the blank longitudinal axis. Positioned. In the state shown in FIG. 1, the mandrel-shaped forming tools 1 and 2 are respectively in the upper or lower dead position.
[0013]
As shown in FIG. 2, the forming tools 1 and 2 are moved toward each other in the direction of the arrow 7 or 8, while the forming tool expands the can blank 5 and reaches the final state shown in FIG. The profile of the forming tool is formed in a corresponding manner into the can stock 5, which has a throat constriction 9 in the lower third, which is the end of the mandrel-shaped forming tool. Determined by the tapering profile of the department. In the final state shown in FIG. 3, the end face of the forming tool is in plane contact. After the deformation of the can material 5, the forming tools 1 and 2 can be pulled back again, with the formed material remaining between the scrapers 3 and 4 and then transported by known conveying means according to the background art. be able to. As is already recognized by FIGS. 1 to 3, the entire surface profile is replicated in the blank 5, not just the profile end of the forming tool, and therefore only the smooth round forming corresponding to FIG. 4 or 5. In addition, the non-circular molding corresponding to FIGS. 6 and 7 can also be a longitudinally grooved molding corresponding to FIG. 8 in the shape range as well as the outer extent, or a can molding according to FIG. 9 or a combination of the aforementioned moldings. Can be produced.
[0014]
FIG. 5 shows an expanded blank 10 with a shape as a protective bead 11, which guides the forming tool introduced from below almost to the other end of the blank and as a corresponding tool. The mandrel-shaped forming tool can be formed by shortening it accordingly. Also in this case, the end surfaces of the mandrel-shaped forming tools that are moved toward each other are oriented perpendicular to the longitudinal axis 6.
[0015]
In FIG. 6, an expanded blank 12 with an asymmetrically corrugated decorative shape is shown. As a ring profile, the constricted portion 13 is not perpendicular to the longitudinal axis 6 but is obliquely located, or the constricted portion is a waveform. This is achieved by using two mandrel-shaped forming tools with correspondingly configured mandrel ends, the end faces of these forming tools being oblique or corrugated with respect to the longitudinal axis 6. It is arranged in a plane that is located or in an obliquely located, possibly twisted plane. Since the forming tool according to the present invention merely expands in the can material, no undercutting is performed, so that the conical tapered mandrel end has the desired forming and constriction. It can be configured according to its position.
[0016]
The material 14 shown in FIG. 7 is also configured asymmetrically and has two non-linear regions 15 and 16, within which the material is tapered to a small diameter, The diameter is constant in the range 17 between them over the length dimension predetermined by the mandrel end formation. In general, the shape and position of the shape can be adapted to the printed image.
[0017]
The can blank 18 of FIG. 8 allows a combination of a rotationally symmetrical decorative shape and a longitudinal profile 19 which is determined by the forming tool extrapolation. In order to manufacture the can material, two mandrel-shaped forming tools can be used, and the end surfaces of these forming tools are located in the final deformation position in the plane 20 inside the can material. In addition to the constriction 21, a corresponding section of the forming tool introduced from below makes it possible to create a lower section 22 that increases in diameter, which is the same as the cylindrical section 23 above the material or Other diameters can be used.
[0018]
The can material 24 has an outer shell. The outer shells extend in a tapered manner, reaching the plane 27 respectively, with the exception of the slight upper and lower partial areas 25, 26 with a cylindrical shape. In other words, the outer profile of the outer can is generally concave.
[0019]
FIG. 10 shows that the two can stocks 5 according to FIG. 4 can also be stacked; the corresponding is also true for the remaining can stocks.
[0020]
The above described can expansion method has the following advantages over the expansion and other methods known from the background art:
The unfolded material is circular in a corresponding can configuration-apart from the shaped longitudinal profile-and is not necessarily polygonal.
[0021]
In addition, the elongation of the thin plate is uniform over the circumference, which allows a greater spread in the same thin plate elongation. There is no apparent height variation. Deformability is possible up to the edge of the material.
[0022]
Furthermore, a desirable uniform sheet thickness reduction occurs in the cylindrical part, whereas the original sheet thickness is still maintained in the shape range at risk of loading.
[0023]
The forming tools used are simple, rugged, and can be easily retrofitted or replaced in existing equipment when a modified shape is desired.
[0024]
The embodiment shown in FIGS. 1 to 10 can be varied arbitrarily, with the exception that the deformation limit is small, apart from the general suitability of the sheet and lacquer. As already mentioned, it is not possible to produce just an undercut shape.
[Brief description of the drawings]
FIG. 1 shows a schematic view of two mandrel-shaped forming tools that are movable relative to each other through a scraper opening, in a starting position before material deformation.
FIG. 2 shows an arrangement corresponding to FIG. 1 with can forming tools moved towards each other in a partial stroke.
FIG. 3 shows the final position of the forming tool when the can body profile is complete.
FIG. 4 shows a side view of a material profile made with the tool shown in FIGS.
FIG. 5 shows the configurability for can stock.
FIG. 6 shows the configurability for can stock.
FIG. 7 shows a configurability for can stock.
FIG. 8 shows the configurability for can stock.
FIG. 9 shows the configurability for can stock.
FIG. 10 illustrates a material with a differentially expanded, stackable, rotationally symmetric shape.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Forming tool, 2 Forming tool, 3 Scraper, 4 Scraper, 5 Can material, 6 Tool vertical axis, 7 arrow, 8 arrow, 9 Constriction part, 10 material, 11 Protective bead, 12 material, 13 Constriction part , 14 material, 15 range, 16 range, 17 range, 18 can material, 19 vertical profile, 20 plane, 21 constricted part, 22 segment, 23 segment, 24 can material, 25 partial range, 26 partial range, 27 plane

Claims (8)

An apparatus for expanding and forming the can body (5), a mandrel-shaped forming tool (1) that can be introduced into the can body (5) to be expanded from one side, and a corresponding tool (2) The corresponding tool (2) can still be introduced into the can body (5) from the opposite side and can be introduced and moved from the one side. and a forming tool can contact heart rod-like, cross-sectional profile of the end portion of both cardiac rod-forming tool (1, 2), depending on the shape type, either the same or complementary to the Ri same der, between both ends of the can body (5), both cardiac rod-forming tool (1, 2) is abutted, cross-sectional profile of the end portion of the forming tool in both heart rod-like (1,2) device according shape, characterized in Rukoto formed between both ends of the can body (5), forming expanding life and death of the can bodies to.   The longitudinal axis of the mandrel longitudinal axis (6) compared to the corresponding subregion where the cross-sectional profile of both mandrel-shaped forming tools (1, 2) is at least partially within their ends and further away from the mandrel ends. 2. A device according to claim 1, characterized in that the device has a small spacing from.   3. A device according to claim 1 or 2, characterized in that the maximum diameter of the mandrel end is smaller, the same or somewhat larger than the diameter of the can body (5) to be expanded.   4. Device according to claim 1, characterized in that the cross-sectional shape is tapered towards the end of the mandrel at least over a partial axial range.   5. Device according to claim 1, characterized in that the mandrel end face is arranged at least partially in a non-orthogonal direction with respect to the mandrel longitudinal axis (6).   6. A device according to any one of the preceding claims, characterized in that the outer surface of the mandrel has at least partly a non-circular cross section. Characterized in that along the scraping molding tool heart rod-winder (3, 4) is movable, device according to any one of claims 1 to 6. A method for expanding and forming a can body (5, 10, 12, 14, 18 and 24), wherein a mandrel-shaped forming tool (1) is introduced into the can body and the corresponding tool (2) is formed. A method for expanding and shaping a can body, characterized in that, in the form of moving in the direction, the device according to any one of claims 1 to 7 is used.

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