US3028827A - Method of manufacturing metal cans - Google Patents

Description

April 10, 1962 E. 1. VALYI METHOD OF MANUFACTURING METAL CANS 5 Sheets-Sheet 1 Filed Oct. 10, 1957 INVENTOR EMEBY. .Z'. VAL Y/ A'ITORNEY April 10, 1962 E. l. VALYl METHOD OF MANUFACTURING METAL CANS 3 Sheets-Sheet 2 Filed Oct. 10, 1957 INV ENTOR z M44 Y O'RNEY Aprll 10,' 1962 I VALY] METHOD OF MANUFACTURING METAL CANS 3 Sheets-Sheet 3 Filed Oct. 10, 1957 ATTORNEY United States Patent 3,028,827 METHOD OF MANUFACTURING METAL CANS Emery I. Valyi, Bronx, N.Y. ARD Corporation, 20 S. Broadway, Yonkers 1, N.Y.) Filed Oct. 10, 1957, Ser. No. 689,303 12 Claims. (Cl. 113-420) This invention relates to the preparation of metal cans and containers of the type used for packaging and storage of food stuffs or other commodities and has for an ob ect to provide a novel and improved method for manufacturing such cans and containers.

This application is a continuation-in-part of my applicatron Serial No. 621,192 filed November 9, 1956 now abandoned, for Can and Method of Manufacture Thereof.

Another object is to provide a method for making cans of the above type in which the steps of bending a fiat blank into cylindrical form and sealing the contacting edges are eliminated.

Various other objects will be apparent as the nature of the invention is more fully disclosed.

In accordance with the invention, metal strip or plate 4 is producing having alternating parallel regions of fiat juxtaposed layers and integral metal. Such strip or plate may be produced somewhat along the lines set forth in my US. Patent No. 2,375,334, dated May 8, 1945. Thus, an ingot or slab of metal is formed having therethrough one or more continuous relatively small openings which may be of any preferred cross-section, as for example, a rectangular cross-section. The surface of these openings is treated or these openings are formed by or filled with a material that by its nature prevents the openings from welding if their juxtaposed surfaces are brought into close contact under considerable pressure. For example aluminum oxide formed in situ by chemical treatment of the inside surface of the openings, or talc may be used as the weld-preventing material with an aluminum ingot or slab; finely divided silica or graphite may be used with a copper or copper alloy ingot or slab; and finely divided silica or mica, or boron nitride may be used with a steel ingot or slab.

Alternately such a strip or plate may be formed with thin openings, by applying, such as by spraying, painting or printing, a thin layer of the Weld-preventing materials previously cited as examples, to one surface of a sheet, by superimposing another like sheet over the first one and by rolling the two oonjointly to a degree suflicient to cause welding together of the two sheets wherever the. weldpreventing substance is not present. This method is illustrated in the above-mentioned patent and is also described in US. Patent, No. 2,690,002, issued to Grenell on September 28, 1954.

The slab of metal, or alternatively, the assembly of superimposed metal plates is rolled to form a flat sheet or coil in which the portions previously treated with the weld-preventing substances produce a laminated structure I 3,028,827 Patented Apr. 10, 1962 cross-section and distribute evenly the weld-preventing substance. In the case of rolling an assembly of superimposed plates, care should be taken in rolling to insure complete welding in the areas not treated to prevent Welding.

The strip or coil so produced may then be cut longitudinally into strips, each containing a single laminated area. Alternatively, the strip may be cut transversely into strips containing several laminated areas each having a length adapted to produce one can body. These strips may be further subdivided and ultimately cut into pieces or blanks adapted to produce a single can body. These can bodies may be formed by separating the laminations of the blank or strip either mechanically with the aid of a mandrel, or by means of an air blast or fluid pressure. The methods of mechanical separation, pneumatic inflation and fluid expansion may be used singly, combined, or applied in sequence, to form the cylindrical body portion required for the finished cans.

The portions of the blank on opposite sides of the lam'inated area form fins along diametrically opposite portions of the can body which may be cut to form narrow ribs and folded fiat against the outer surface of the can body. Ends in the form of substantially flat closures are then applied to the open ends of the cylindrical body portions and mechanically folded, crimped, seamed, or otherwise secured in the usual manner to produce cans or containers of the desired configuration.

Thus, a can or container is produced characterized by a body of seamless construction in place of the present product which usually has a soldered or welded seam. In place of the seam, the can body according to the invention will have two reinforcing ribs of metallurgical characteristics substantially identical with those of the other portions of the body, such characteristics being that of a metal rolled essentially in one direction from of juxtaposed individual layers While the adjacent portions that were not so treated produce an integral structure alongside the laminated structure. The operation of rolling to produce this sheet or coil may be performed hot or cold depending upon the nature of the specific metal to be rolled, generally in keeping with procedures known to those skilled in the art of rolling metal. If the grain structure of the slab requires rolling in more than one direction, any cross rolling that is performed must be carried out exactly perpendicular to the longitudinal axis of the portions treated with weld-preventing substance so as to prevent distortion of the passages. In rolling the slabs as above described, an appreciable degree of reduction in cross-section of the slab should be made as early a block of substantially greater thickness.

The article and the steps in forming it will be better understood from the following description, taken in connection with the accompanying drawings in which a spe cific embodiment has been set forth for purposes of illustration.

In the drawings:

FIG. 1 is a transverse section through a mold showing a slab or casting and weld-preventing inserts therein;

FIG. 2 is a broken perspective view of the slab or casting of FIG. 1;

FIG. 3 is a broken perspective view of the coiled strip formed by rolling the slab casting of FIG. 2 showing severance lines for forming can blanks or strips;

FIG. 4 is a view similar to FIG. 3 illustrating a strip of single can forming width indicating severance lines for making a single can blank;

FIG. 5 is a perspective view on a larger scale of an individual can blank cut from the coiled strip of FIGS. or 4 and indicating shear lines along which the corners may be cut for the purpose to be described;

FIG. ,6 is a broken perspective view of a single can blank taken on a larger scale showing the step of slightly opening or inflating the end of the blank;

FIG. 7 is a broken perspective view showing the step of forcing the blank over a mandrel for continuing the opening thereof;

FIG. 8 is a transverse section taken on the line 8-8 of FIG. 7; 7

FIG. 9 is a broken perspective view showing a final stage in opening the blank on the mandrel to form the can body;

FIG. 9a is a partial section taken on the line 9a)a of FIG. 9 illustrating the folded fin or rib;

FIG. 10 is a broken perspective view illustrating an alternate method of opening or expanding the blank to form the can body;

FIG. 11 is a perspective view of the can body with an end closure in place prior to crimping;

FIG. 12 is a similar perspective view of the completed can showing one end closure secured by crimping and the other end in juxtaposed position prior to closing the can;

FIG. 13 is an enlarged section taken on the line 1313 of FIG. 12;

FIG. 14 is a perspective view of an expanded tubular body as produced from the strip of FIG. 4 indicating severance lines for forming single can bodies;

FIG. 15 is a broken perspective view of a casting similar to FIG. 2 but having four spaced superposed inserts;

FIG. 16 is a broken perspective view on a larger scale of a can body formed from the casting of FIG. 15; and

FIG. 17 is a broken perspective view of a pair of superposed sheets prior to rolling illustrating a further embodiment of the invention.

Referring to the drawings more in detail, FIG. 1 shows a casting 10 cast in a mold 11 around a series of weldpreventing inserts 12. The ends of the inserts 12 seat in recesses 17 in the mold to hold the inserts in place during pouring.

The slab 10 after removal from the mold and with the inserts still in place as shown in FIG. 2 is rolled longitudinally by known technique to form the sheet 20 of FIG. 3 with walls or laminations 21 and 22 separated by a slit 23 in the areas of the now flattened inserts.

During the rolling the inserts 12 are crushed to a weldpreventing powder form keeping the walls 21 and 22 from welding together.

The strip 20 may be of substantial length depending upon the amount of elongation produced by the rolling operation and is shown as formed into a coil 19 for convenience. It is to be understood that the coiled sheet may be shipped if desired in this form to a remote point wherein the succeeding stages of the can-forming operation may take place or the can may be completed prior to such shipping.

The strip 20 may first be severed as by cutting, shearing or breaking along severance lines 25 to form individual strips 24, as shown in FIG. 4, which may then be separated along severance lines 26 into single can blanks 28 either before or after opening, or the strip 20 may be severed transversely along severance lines 27 into strips of multiple can width which are then severed along severance lines 25 into single can blanks 28, or the transverse and longitudinal severance may take place simultaneously to produce the single can blank 28 of FIG. 5.

The corners of the blank 28 (FIG. may be out if desired along lines 29 for the purpose to be described, although such removal of the corners may be omitted when this step is found to be unnecessary.

The strip or blank 28 may now be opened by mechanical, pneumatic or hydraulic means to expand the slit 23 and form the walls 21 and 22 into the shape of a can body. One method of so opening the strip or blank is illustrated in FIGS. 6 to 9.

In accordance with FIG. 6 one end of the slit is first opened very slightly by means of a air jet 30 which is directed toward the slit and separates the leading edges of the walls 21 and 22. In some instances the walls may be opened partially or completely along their entire length by means of this air jet or fluid pressure may be applied to the slit 23 for separating the walls 21 and 22.

The strip or blank with the separated walls of FIG. 6 may then be guided over a mandrel 31 as illustrated in FIGS. 7 and 8 by suitable feed means, such as rollers (not shown) to cause the walls to be progressively opened into substantially cylindrical form, or to such other form as may be required for the can body.

Opposite sides of the can body may be pushed inwardly to facilitate the forming of the walls 21 and 22 into the desired shape. If the sides are so pushed against the mandrel the intervening portions of the walls 21 and 22 may be extended away from the surface of the mandrel so that it is not necessary that the mandral have the full final form which the can body is to assume.

The areas of the sheet beyond the flattened slit 23 produce longitudinal fins 32 which extend along the side walls of the cylindrical body. Before or during the expanding operation these fins may be cut close to the can body as indicated by dotted line 34 in FIGS. 7 and 8 to form narrow ribs 35 to render the corresponding wall area resistant to rupture in subsequent can body forming steps. In the final form such as indicated in FIGS. 9 and 9a the ribs 35 may be folded over or crushed against the side walls of the can as by pairs of rollers 36.

An alternate means for expanding the blank into cylindrical form is illustrated in FIG. 10. This method may be used in instances where the entire length of the slit 23 is opened such as by fluid means so as to provide sufficient clearance for the insertion of a roller. The blank is then introduced between rollers 38 and 39 which are actuated to roll the blank circumferentially so as to complete the opening of the walls 21 and 22 into full cylindrical form. It is to be understood that the strip 24 may be opened by the steps indicated in FIGS. 6 to 9 to form a long tube 48 as shown in FIG. 14 which may then be separated along severance lines 49 into individual can lengths. or the blanks 28 of FIG. 5 may be opened individually after severance to form can bodies.

Also the walls may be separated to a limited extent prior to severance into individual can blanks and the opening of the walls completed after severance.

It is to be understood of course that these methods of opening the blank are purely illustrative and that the walls may be formed by any convenient means into the shape required for the ultimate can.

The ends of the cylindrical body 40 formed as above described are now bent to form peripheral end flanges 41 and 42 as illustrated in FIG. 11 and a can end or bottom 44 in the form of a metal disk is placed against the end flange 41 and folded over or crimped as indicated in FIGS. 12 and 13 in accordance with the usual practice of forming a closed end can. The top 45 may be secured in a similar manner after the can has been filled.

The corners of the blank may be removed as indicated by lines 29 of FIG. 5 to a depth to intersect the slit 23 so as to form notches 47 in the end flanges 41 and 42. These notches are adapted when the flanges are crirnped over as indicated in FIG. 13 to eliminate the extra thickness of the metal which would otherwise be present at that point due to the ribs 35. Such notching of the blank may be omitted if the thickness of the metal is such that the presence of the ribs 35 at the point of crimping is not objectionable.

In the event that the rolled strip of FIG. 3 is shipped to the point of packaging, the can-forming steps illustrated in FIGS. 6 to 13 may take place at the packaging point thereby reducing the shipping space which would otherwise be required for shipping the formed cans.

The can end has been shown in FIG. 13 as attached to the end of the can 40 by a specific type of crimping. It is understood of course that the end may be secured in various ways which are common in the art.

FIGS. 15 and 16 illustrate the steps in a method of forming a two-compartment can. In accordance with this embodiment the slab or casting 50 is provided with pairs of weld-preventing inserts 51 which are in spaced juxtaposed relationship and which have a metal wall 52 therebetween. When this slab 50 is rolled in accordance with the procedure above described to form a rolled sheet and then opened into the form of a can, as shown in FIG. 16, the intermediate metal wall 52 forms a diaphragm 53 (FIG. 16) which acts as a partition to divide the can body longitudinally into two separate compartments. Ends may be applied to this can body in any suitable manner.

FIG. 17 illustrates an alternate method for forming the rolled sheet in which a pair of metal sheets 55 are superimposed with weld-preventing material 56 disposed therebetween in the areas corresponding to the slit 23 of FIG. 3. These sheets may be roll-welded to form a composite sheet similar to the coiled strip of FIG. 3.

What is claimed is:

1. The method of making a metal can comprising forming a metal blank having a passage extending therethrough containing a weld-preventing material, rolling said blank to form a flat sheet having a pair of walls separated by a slit in the area corresponding to said passage, and having integral fin-forming areas adjacent said slit, said walls being prevented from welding together during the rolling operation by said weld-preventing material, separating said walls to form an open end can body having integral longitudinal fins, subjecting said fins at a stage subsequent to the initial separation of said walls to a compressing force adapted to deform said fins to an extent to conform them nearly, but not completely, to the contour of said walls, while leaving raised metal ribs extending longitudinally along said walls and thereby render the corresponding wall area resistant to rupture in the subsequent can body forming steps, flaring at least one end of said can body to form a peripheral flange thereon, applying an end closure to said flange, and securing said end closure thereto.

2. In the method set forth in claim 1 the additional step of removing the corners of said fin-forming areas along a line intersecting said slit.

3. The method of making a metal can as set forth in claim 1 in which said end closure is secured to said peripheral flange by crimping.

4. The method of forming metal cans which comprises forming a metal blank having a plurality of parallel passages extending longitudinally therethrough and containing a weld-preventing material, rolling said blank longitudinally of said passages to produce an elongated fiat sheet having walls separated by narrow slits in the areas corresponding to said passages and having integral fin-forming members between and adjacent said passages, severing said sheet along said fin-forming members to form strips, separating said walls to form can bodies having integral longitudinal fins, subjecting said fins at a stage subsequent to the initial separation of said walls to a compressing force adapted to deform said fins to an extent to conform them nearly, but not completely, to the contour of said walls, while leaving raised metal ribs extending longitudinally along said walls, and thereby render the corresponding wall area resistant to rupture in the subsequent can body forming steps, flaring at least one end of each of said bodies to form a peripheral flange thereon, applying an end closure to said flange, and securing said end closure thereto.

5. The method of forming a metal can from an integral blank having metal. walls separated by a narrow slit in selected areas only and integrally joined in other fin-forming areas which comprises severing said blank into can body lengths, separating said walls to form can bodies having integral longitudinal fins, subjecting said fins at a stage subsequent to the initial separation of said walls to a compressing force adapted to deform said fins to an extent to conform them nearly, but not completely, to the contour of said walls, while leaving raised metal ribs extending longitudinally along said walls and thereby render the corresponding wall area resistant to rupture in the subsequent can body forming steps, flaring at least one of each of said can bodies to form a peripheral flange thereon, applying an end closure to said flange, and securing said end closure thereto.

6. The method of making a metal can as set forth in claim 5 in which said fins are trimmed to remove excess metal prior to the step of deforming said fins.

7. The method set forth in claim 5 in which said severing step occurs prior to the step of separating said walls.

8. The method set forth in claim 5 in which said severing step takes place after said walls have been at least which comprises forming a metal member having a pair of super-imposed longitudinal passages extending therethrough and separated by an intervening wall and containing a weld-preventing material, rolling said strip longitudinally of said passage to form an elongated thin metal st-rip having outer walls and an intermediate wall separated by upper and lower narrow slits in the areas corresponding to said passages, expanding said outer walls to form a can body in which said intermediate wall constitutes a transverse diaphragm separating said body into two chambers, said body having integral longitudinal fins, subjecting said fins at a stage subsequent to the initial separation of said outer walls to a compressing force, adapted to deform said fins to an extent to conform them nearly, but not completely, to the contour of said outer walls, while leaving raised metal ribs extending longitudinally along said outer walls and thereby render the corresponding wall area resistant to rupture in the subsequent can body forming steps, adapting at least one end of said body to receive an end closure, and securing said end closure thereto.

10. The method of making a metal can body comprising forming a metal blank having a passage extending therethrough containing a weld-preventing materiaLrolling said blank to form a flat sheet having a pair of walls separated by a slit in the area corresponding to said passage, and having integral fin-forming areas adjacent said passage, said walls being prevented from welding together during the rolling operation by said weld-preventing material, separating said walls to form a can body having integral longitudinal fins, subjecting said fins at a stage subsequent to the initial separation of said walls to a compressing force adapted to deform said fins to an extent to conform them nearly, but not completely, to the contour of said walls, while leaving raised metal ribs extending longitudinally along said walls and thereby render the corresponding wall area resistant to rupture in the subsequent can body forming steps, and flaring at least one end of said can body to form a peripheral flange thereon adapted to receive an end closure.

11. The method of forming metal can bodies comprising forming -a metal blank having a plurality of parallel passages extending longitudinally therethrough and containing a weld-preventing material, rolling said member longitudinally of said passages to produce an elongated fiat sheet having walls separated by narrow slits in the areas corresponding to said passages and having integral fin-forming members between and adjacent said passages, severing said sheet along said fin-forming members to form strips, separating said walls to form can bodies having integral longitudinal fins, subjecting said fins at a stage subsequent to the initial separation of said walls to a compressing force adapted to deform said fins to an extent to conform them nearly, but not completely, to the contour of said Walls, While leaving raised metal ribs extending longitudinally along said outer walls and thereby render the corresponding wall area resistant to rupture in the subsequent can body forming steps, and flaring at least one end of each of said bodies to form a peripheral flange thereon adapted to receive an end closure.

12. The method of forming a metal can body from an integral blank having metal walls separated by a narrow slit in selected areas only and integrally joined in other fin-forming areas which comprises severing said blank into can body lengths, separating said walls to form can bodies having integral longitudinal fins, subjecting said fins at a stage subsequent to the initial separation of said walls to a compressing force adapted to deform said fins to an extent to conform them nearly, but not completely, to the contour of said walls, while leaving raised metal ribs ex- 7 tending longitudinally along said outer walls and thereby render the corresponding wall area resistant to rupture in the subsequent can body forming steps, and flaring at least one end of each of said can bodies to form a peripheral flange thereon adapted to receive an end closure.

References Cited in the file of this patent UNITED STATES PATENTS 3 Lewis et a1. a Oct. 28, 1930 Maskrey Dec. 12, 1933 Hothersall Oct. 20, 1942 Atkinson Feb. 22, 1944 Pearson July 15, 1947 Thornburgh Nov. 9, 1948 Kruse Jan. 4, 1949 Laxo Nov. 23, 1954 Peters et a1 Feb. 22, 1955 Campbell Aug. 21, 1956 FOREIGN PATENTS Australia Nov. 1, 1956

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