US2112085A

US2112085A - Thin metal container

Info

Publication number: US2112085A
Application number: US111788A
Authority: US
Inventors: John H Friden
Original assignee: SUN TUBE CORP
Current assignee: SUN TUBE Corp
Priority date: 1936-11-20
Filing date: 1936-11-20
Publication date: 1938-03-22
Anticipated expiration: 1955-03-22

Description

March 22, 1938. H R EN 2,112,085

THIN METAL CONTAINER Filed Nov. 20, 1936 3 Sheets-Sheet 1 INVENTOR: Johnlifizd'n 1n's A TTORNEY.

March 22, 1938. a. H. FRIDEN 2,112,085

THIN METAL CONTAINER Filed NOV. 20, 1936 3 Sheets-Sheet 2 $119 ATTORNE Q March 22, 1 938. I FRmEN v 2,112,085

THIN METAL CONTAINER Filed Nov. 20,- 19,36 5 Sheets-Sheet 3 fiIkAITORNEY.

Patented Mar. 22, 19 38 John H. Fridn, Maplewood, N. The Sun' I'nbe Corporation, corporation of New Jersey J., assignor to Hillside. N. J., a

Application November 20, 1936, Serial No. 111,788 8 Claims. (01. 221-60) This invention relates to thin walled metal containers of the collapsible type intended for single-use purposes and to the way of producing the same. It has particular reference to containers I of the sort mentioned, adapted to retain liquids or other fluid substances which are to be completely dispensed and used when the container is first opened.

A particular object of the invention has been to develop a container of the character specifled which can be quickly and economically produced in, large quantities, has an integral closure than can be readily opened without the use of implements, is completely air-tight and liquidtight, is sufilciently sturdy to prevent accidental opening, and, when intentionally opened, provides a relatively large passage for the discharge of its contents. 1

Containers of the type contemplated are admirably suited for the packaging of whisky and the like. They are non-refillable since a portion of the metal around the integral closure must be torn to open the container. Theyare relatively inexpensive and may be discarded after use without danger of cutting persons handling them. Moreover, the space occupied by the container, both when filled and when empty, is considerably less than the space occupied by a glass container. The new container is ideally suited for use by bars, railroad club cars, restaurants and the like desiring to assure their patrons that they are receiving the genuine brand asked for. A

suitable quantity of the liquor to form one drink may be placed in a small, individual container of the type contemplated and this container, bearing prominently the label or mark of a reliable producer, printed directly thereon, may be opened, without implements, right before the eyes of the patron, or even by the patron himself.

It will be understood that while the packaging of liquors and the like presents an ideal field for the use of the improved container, it is by no means limited to this field but may be used to package various other fluids and even solids in a fluid state. I

Numerous difliculties have arisen in the development of the improved. container both from the standpoint of thearticle itself and the manner of producing the same. It has been a primary object of the invention to overcome these difiiculties. Toward this end there has been provided a container which, while sturdy and reliable for ordinary handling and shipment, may be very easily opened by the use of the thumb-nail or finger-nail. This opening operation, moreover,

may be eiiected in such a contents of the, package will be spilled but its contents may quickly and safely be discharged into a glass or other receptacle.

In the production of the container it has been an object to so simplify the operations that the container may bemanufactured in large quantitles at low cost. Toward this end it is largely produced by a single extrusion operation followed by a minimum of -finishing operations. This phase of the invention embraces not only improved methods but also novel relationships between the parts of the apparatus for producing the container.

These and other objects and advantages of the invention will become more apparent from the detailed description of an illustrative form of the same which will now be given in conjunction with the accompanying drawings in which: I

Figure 1v is a perspective view of the improved container.

Figure 2 is a vertical section through the axis of the container.

Figures 3, 4 and 5 are views partly in section and partly in elevation, showing the relation between the punch and die at diiferent stages in the operation of the press.

Figure 6 is a detail showing certain pin controlling cams and is taken along the line 66 of Figure 7, and

Figure 7 is a view, partly in vertical section and partly in elevation, of portions of an extrusion press constructed and employed in accordance with the invention.

Referring now to the drawings, the improved container is preferably formed witha cylindrical side wall Ill and a shoulder I I provided at one end to partially close the tube. The shoulder I I is inclined slightly to a true transaxial plane. The inclination of this shoulder need not be, and preferably is not, as great as in the usual collapsible tube construction for the packaging of tooth paste and the like; it may suitably be an angle of, say 10 to 15 to the transaxial plane, or even less. If desired, it might even be substantially perpendicular to the axis of the container. At the center of the shoulder ii there is provided a readily removable closure in the form of a flat disc I2, which is joined integrally with the metal of the shoulder by a thin, short, annular neck I3.

This container lends itself readily to production by an extrusion operation which is capable of forming the shoulder II, end closure I2, and neck portion I3 in a smooth, completely finished state within less than a second. The opposite or open way that none of the I end of the tube lilwill terminate in an irregular edge I! upon completion of the extrusion opera-.

' tion and, therefore, in forming the flnishedc'ontainer.

tainer a small section or annular band II will be removed, and the tube thus trimmed to length, by a simple cutting tool, of a type well-known in the art. In using the new container, the liquid or other contents will be introduced through the open end left upon the removal of the ring I! and this end may then be sealed in any convenient way, as by simply folding and crimp-, ing'the edges together in a manner well known in connection with other forms of collapsible tubes. Any suitable design, such as designated II in Figure 1, may be appropriately applied to'the surface of the wall III. This may include a base coating of any selected color and any printed matter which it may be desired to add to the tube for advertising purposes and by way of instructions, Methods well known in the art may be employed for the coating and printingoperations.

If the tube is to be used for the packaging of liquors or other potable or edible products it is preferably formed of substantially pure tin. However, the container may be made of other readily extrudable metals or combinations or alloys of metals suitable for use in connection with the particular substance to be packaged.

While I do not desire to ,be limited to any specific dimensions or wall thicknesses of the various portions of the container, a form which has been found most excellent for the packaging of a suitable quantity of liquor to constitute one drink is a tube having a diameter of 1 inch and a wall thickness of about .003 of an inch. The package when filled has an overall length of about 4 inches. Shoulder II should preferably be considerably thicker than the wall l0 so as to provide a desired rigidity. It may well be about .025 of an inch thick. End closure I2 is preferably of even greater thickness and may, for example, be

about .050 of an inch thick. The neck portion l3,

great length. All that is required is sufficient.

space for the insertion of .the thumb-nail between the inner surface of the closure I2 and the inner rim of the shoulder II. For this purpose it need not be greater than .050 of an inch in length and may even be shorten-down to, say, 0.25 of an inch. In view of the thinness 'of the metal of the neck, it should be as short as possible so as to avoid unduly weakening the con- It might be made as long as .10 of an inch but due to difliculties of manufacture, it is very desirable to limit the length of the neck l3 to only sufllcient to allow insertion of the thumb-nail. While the diameter of the closure l2 may be varied to suit particular requirements, depending upon the fluidity of the contents and the speed with which it is desired to discharge the contents, it has been found that a closure of about of an inch in diameter is ideally suited for a package intended to contain liquor. If it is desired to discharge the contents more slowly and, for example, require either squeezing or shaking of the tube to accomplish it, the closure may be made quite small, say .10 of an inch in diameter. A package of the character specified, having the dimensions indicated, will retain about am of a pint of liquid. Obviously.

the size of the container and the dimensions of various portions of the container may be varied within relatively wide limits without departing from the general principles and scope of the invention. However, the thickness and length of the neck portion II is of considerable importance and should not be varied materially without regard to the considerations mentioned.

Various manufacturing diiiiculties have been encountered in the production of the improved container. As previously stated, the container is primarily formed by an extrusion operation involving the use of a punch II and a die is. These -may suitably be embodied in an extrusion press of appropriate character, such as the one disclosed in my prior Patent No. 2,023,879, granted December 10, 1935. Reference may be had to 'that patent for details of construction. Only those portions having a direct bearing upon the present invention are shown herein. The die is provided with a recess 20, which is of slightly greater diameter than that of the lower extremity of the punch. This, as is understood in the art, is slightly larger than the main shank of the punch, by either providing a head or a slight outward taper at the lower endof the punch. The distance between the corner 2i or point of largest diameter of the punch and the wall 20 of the' die will determine the thickness of the metal of the wall ill of the tube. This thickness may be very accurately determined and maintained. It should be pointed out, however, that it is not possible to confine accurately within very definite limits the thickness of any wall that is disposed substantially transversely to the direction of movement of the punch. Such a wall may vary as much as .020 of an inch in thickness in the extrusion of a large quantity of tubes. This is due in part to the eflect of a variation in temperature and in part to variations in the metallurgical structure of the slugs being extruded. Relatively small changes in temperature will bring about variations in the length of the punch and these will result in corresponding differences in the thicknesses of transversely disposed walls. -The ease or difficulty with which slugs may be extruded is affected not only by temperature but to an even greater extent by variations in the grain and hardness of the slugs. It has been found that slugs of identically the same composition may vary widely in their hardness and extrudability. When a relatively hard slug is encountered, the parts of the press structure-will yield or spring to a greater extent, than when an easily extrudable slug is used, and hence the punch will not descend as far into the die.

For the production of the improved container the punch is provided with a projection 22 extending beyond a shoulder 23 at the lower end of the punch. The projection is of the appropriate length and diameterto form the end closure l2 and neck l3 of the tube while the shoulder 23 is of the appropriate form to produce the shoulder ll of the tube in cooperation with a slightly tapered bottom portion 24 of the die recess. The projection 22 of the punch may suitably be formed separate from the main shank of the punch on a small plunger element 220 slidable to a limited extent within a passage 22i extending through the punch. This, as explained in my prior patent, is for the purpose of enabling a blast of air to be forced through the punch and outwardly around the projection 22 to strip the exwtube described, therefore, this difference should" be only briefly described here.

is retracted to its elevated position.

truded tube from the punch as the latter The die has extending through -it, from the center of the bottom of the recess to the bottom of the die, an opening or passage 26, whichis of only slightly greater diameter than the projection 22. The difference between the diameter of the passage 26 and that of the projection 22 will determine the wall thickness of theneck portion l3 of the tube. For the production of the typical be .003 of an inch; Within the passage 25 is a 'slidable pin 26 forming a movable section of the die bottom. This pin is adapted to shift in the course of an extrusion operation and for this purpose may be controlled by suitable cams as well as by a spring, if desired, in the manner explained in my prior Patent No. 2,023,879. 'The connections for accomplishing this control are fully set forth in that patent and will, therefore, They include a rod formed in several sections, 21, 28 and 29,,the latter two of which pass through an adjustable sleeve 36. The lower end of section 29 is adjustably connected with one end of a lever3| mounted on the frame and having its other end connected with the lower end of a vertically extending rod 32. Thisrod is surrounded by a spring 33 ent, nevertheless, for the purpose of successfully forming a container of the type constituting a a part of the present invention, it is necessaryto time the operation of the cams, which control the pin 26, somewhat differently from the timing explained in my prior patent. In the operation of the machine to produce the improved container, the

cams

38 and 39 for controlling the pin 26 are so constructed and arranged that when the punch first engages the upper surface of the slug, the top of the pin 26 N flush with the innermost edge of the-"die surface 24 or will be elevated slightly'above this to engage the under surface of the slug. If it is held in the first position mentioned, the subsequent downward movement of the punch will first bend the slug slightly to conform with the concavity of the diebottom. The projection 22will then penetrate the material of the slug and squeeze the metal aside until the section between the bottom of the projection 22 and the top of the pin 26 is substantially equal in thickness to the desired thickness of the closure l2. Should the top of the pin 26 be initially elevated into engagement with the bottom of the slug, it will be permitted to drop under the pressure of the projection 22,

exerted through the slug, until it is substantially flush withthe innermost edge of the surface 24. From this point the operation is the same as before, i. e., the metal is squeezed with the pin held in this position until the closure portion l 2 of the tube isproduced in substantially its final form. A part of this squeezing may take place simultaneously Withthe depression of the pin in this mode of operation. In the course of accomplishing this formation of the closure portion l2, the

ure 4.

- movement of the

shoulders

23 and 24, although due to sive resistance to extrusion through such a small will be held either substantiallyv shoulder 23 will have commenced the squeezing of the rest of the slug to start the metal upwardly along the punch in the manner indicated in Fig- Now, after the slug has been reduced to the desired thickness between the end of projection-22 and the top of pin 26, the cams will permit the pin 26 to descend in unison with the further movement of the punch. The total amount of downward movement of the pin below the inner edge of shoulder 24 is relatively small, being only equal to the thickness of the closure l2 and the During this downward pin the metal to form the neck i3 may be supplied in several ways. It may be partly supplied by the downward extrusion of some ofthe metal being squeezed between the the exceslength of the neck I3.

passage it is questionable whether much, if any, of the metal is supplied in thisway. It is probably supplied principally, if not entirely, by the drawing .or necking action produced by the downward movement of the closure portion l2 of the 'tube in'advance of the projection 22. If desired the downward movement of the pin 26 may take place at a slightly slower rate than the downward movement of the punch, or the downward movement of the pinmay be arrested a trifle before the downward movement of the punch so that a slight, additional squeezing action takes place between the bottom of the punch and the top of the pin. This, then, will provide a slight upward extrusion. of a portion of the metal between these surfaces.

However, here again the resistance to extrusion through the slender passage is so great that it is not desirable to attempt to extrude any substantial quantity of metal in this way. My experiments have shown that it is not possible to completely form the neck I3 by the upward extrusion of metal squeezed from-between the bottom of the projection 22 and the bottom of a solid die or the top of a pin 26 that is held stationary. The pressure required to extrude metal through such a narrow passage as to produce a neck having a wall thicknessof about .0015 of an inch is so great that either the punch or the die, or both, would break before a sufficient portion of the incompressible metal,could be displaced through this passage. It is for this reason that it is important to reduce the metal between the bottom of projection 22 and the top of pin 26 to substantially the thickness of the closure fore the bottom of projection 22 reaches the plane of the inner edge of shoulder 24. Even before this point is reached, the passage for the outward flow of metal is reduced to such an extent that the extrusion pressure would be prohibitively high. Moreover, the resistance of the metal to flow even through passages of sufficient dimension to normally allow for extrusion may become excessive if a slight outward taper to the passage is not provided. Accordingly, I form the recess '20 with a very slight outward taper from bottom to top and I form the punch shoulder 23 at a slightly greater angle to the transaxial plane than the shoulder 24. The necessity for this illustrates the difiiculty, or even impossibility, of extruding from a relatively large passage such as that between projection 22 and pin 26, into the very thin passage between projection 22 and die opening 25.

The control of the pin 26 may, if desired, be entirely through the earns 38 and 39, although the spring 33 is preferably included in the control- 'l2, at least be- 4 I, ling linkage. Should this spring be provided, it will be. understood that the pin 20 will be positively held by the cams at a point with its top flush with the inner edge oLshoulder 24 until the metal attains the proper thickness between this pin and projection 22. A drop may then be provided on the cam to allow the pin 25 to be forced downwardly against the action of the spring until the pin is depressed to the extentrequired to form a neck i3 of the desired length. At this point .further downward movement of the pin may be arrested by the coaction of positive stops, as explained in my prior patent, but at this time the downward movement of the punch should also be substantially completed. Due to the precise lower limit of the punch, as has been explained, it is preferable to so adjust the positive'stops that they are engaged only when the punch travels to substantially its extreme lower limit for any particular set-up of the mechanism.

As also explained'in my priorpatent, the upward movement of the pin 26 should be delayed -until the punch l8 has been partially retracted so that a slight slippage is produced between the punchand the extruded container before the latter is caused to follow the upward movement of the punch. This allows for the easy removal of container by a short annular neck having a wall.

the tube by the air blast means at the appropriate time.

In connection with the formation of the neck l3, it should be observed that there is a fairly definite limit to the length of neck that can be produced. As stated before, an attempt toextrude much metal through such a narrow passage as is provided between the projection 22 and the passage 25 will result in the breakage of the punchor die, or both. Moreover, an attempt to lengthen the neck by a drawing or necking operati on is apt to result in the fracture of the neck at some point, thus rendering the tube defective. My experiments indicate that the maximum length to which the neck l3 may be safely extended when its thickness is not more than .0015 of an inch is of an inch.

While the preferred form of my improved container and a preferred method of and apparatus for producing the same have been disclosed in considerable detail, it will be understood that .various changes may be made 'in both the article and the process without departing from the general principles and scope of the invention. The terms and expressions used herein have been used as terms of description and not of limita tion. 1

What I claim is: j

1. As an article of manufacture a thin-walled,

collapsible, tubular, metal container having a shoulder at one endand a solid, disc-like closure integrally connected with said shoulder of the thickness of less than an extrudable dimension, said neck holding said closure spaced from said shoulder only a suilicient distance to enable the;

passage of a thumb nail readily between said closure and shoulder.

2. As an article of manufacture a thin-walled, collapsible, tubular, metal container having one end completely closed by integral parts thereof.

a,11a,oss v readily penetrated by the thumb nail. the neck being of a length suflicient only for the ready passage of the thumb nail between said shoulder and closure portions.

3. As an article of manufacture a thin-walled. collapsible, tubular, metal container having one end completely closed by integral parts thereof connecting said shoulder and closure portions, said neck extending axially of the tube and having a wall thickness throughout of less than an extrudable dimension, the construction and arrangement of said shoulder, neck and closure portions being such as to enable piercing of said neck by the thumbnail without substantially altering the relative positions of said portions. I

5. As an articleof manufacture a thin-walled, collapsible, tubular, metal container having one end completely closed by integral parts thereof including an annular shoulder portion, a central closure portion, and a short, thin neck portion connecting said shoulder and closure portions, said neck extending axially of the tube and having a. wall thickness throughout of not substantially more than .0015 inch but being sufiiciently short to. resist accidental shifting of said closure portion with respect to the shoulder portion.

6. As an article of manufacture a thin-walled, collapsible, tubular, metal container having one and completely closed by integral parts thereof including an annular shoulder portion, a central closure portion, and a thin neck portion connecting said shoulder and closure portions, said neck extending axially of the tube and having a wall thickness throughout of not substantially more than .0015 inchand being not more than about .050 inch long.

'7. As an article of manufacture a thin-walled, collapsible, tubular. metal container having one end completely closed by integral parts thereof including an annular shoulder portion, a central ing said shoulder and closure portions, said neck extending axially of the tube and having a wall thickness throughout of between .001 and .002 inch and a length of between .025 and .10 inch.

'8. As an article of manufacture a thin-walled, collapsible tubular, metal container having one end completely closed by integral parts thereof including an annular shoulder portion, a central closure portion, and a thin neck portion connect ing said shoulder and closure portions, said neck extending axially of the tube and having a wall thickness throughout of between .001 and .002 inch, said shoulder and closure portions having a thickness of at least .020 inch, and said neck portion having a length not substantially greater than required for the insertion of the thumb nail between said closure portion .and shoulder portion.

JOHN H. FRIDEN.