US2162776A - Apparatus for and method of making thin metal containers - Google Patents

Description

J. H. FRIDEN APPARATUS FOR AND METHOD OF MAKING THIN METAL CONTAINERS June 20, 1939.

Original Filed Nov. 20, 1936 3 Sheets-Sheet 1 Zinbentor June 20, 1939.

J. H. FRIDEN I 2,162,776

APPARATUS FOR AND METHOD OF MAKING THIN METAL CONTAINERS Original Filed Nov. 20. 1936 3 Sheets-Sheet 2 A Smmutor June 20, 1939. J. H. FRlDEN 3 2,162,776

APPAR Tus FOR AND METHbD OF MAKING THIN METAL CONTAINERS Original Filed Nov. 20, 1936 3 Sheets-Sheet 3 Patented June 20, 1939 APPARATUS FOR THIN METAL John B. Frldn, Maplewood, N. 1., ,assignor to The Snn'lnbe Corporation; Hillside, N. J., a corporation of New Jersey I Original application November- 20, 1936, Serial No. 111,788. Divided and this application November 9, 1937, Serial No. 173,634

9 Claims; 7 (c1. ant- 1o This invention relates to apparatus for a method of producing thin walledmetal icontainers of the collapsibletype intehdedlforsim' gle-use purposes. Ithas particular reference to 5; the productionoi containers of the sort men tioned, adapted to retain liquid s or other fluid substances which arejto be completely dispensed and used when the container'is first opened.

A particular object of' the invention has to provide for' quickly and economically producing in large quantities containers of the character mentioned having integral closures that can be readily opened without the use of implements, are completely air-tight and liquid-tight,

iii: are sufliciently sturdy to prevent accidental opening, and, when intentionally opened-,1provide a relatively large passage for the discharge of their contents. r

For further details as to the features and advantages of the container which the present fimproved method and apparatus are especially adapted to produce, reference may be had to the copending application S. N. 111,788, filed on November 20, .1936, Patent 2,112,085, issued March 221938, of which this applicationis .a

division.

In the production of the container it has been.

an object. to so simplify theo'perations-that the containermay be manufactured in large quasi-- tities at low cost. Toward thisenddteis largely produced by a single extrusion operation followed by a minimum of finishing operations. This phase of the invention embraces not only imjproved methods but also novel relationships between the parts ofthe apparatus for producing the container. 1

These and other objects and advantages of cordance with the invention.

trusion press constructed and employed in Referring-now tothe-drawing's, the improved container, which the present method and apparatus are particularly designed to 'produceis preferably formed with a cylindrical side wall I.

and a shoulder H provlded at one end to'par tlally close the: tube. The shoulder ii is, in-

clined slightly to a true transaxial plane.

inclination of this shoulder need not be, and preferably is not, as great as in the usual col- .lapsible tube construction ;for'the 'packaging of tooth paste and the-like; it may suitably be an angle of, say IO-to 15tothetransa xial plane,

or, even less. If desired, it might even be substantially perpendicular-to the axis of the container. At the center of the shoulder I I there is provided a readily removable closure in the form of a fiat disc l2, which is joined integrally with the metal of the shoulder by a thin, short, annular neck l3. 3

This container lends'itself'readily to production by an extrusion operation which is capable of forming the shoulder ll, end closure i2, and neck portion it in a smooth, completely finished state within less than asecondp The opposite or'open end of the tube ill will terminate in an the invention will become more apparent from the detailed description of an illustrative form of the samewhich will-no w beigiven in conjunction with the accompanying drawings in which: Figure 1 is a perspective view of the improved container. l 0 Figure 2 is a vertical section through the axis of the container.

Figures 3, 4 and 5 areview's partly in section and partly in elevation, showing the relation be-- tween the punch and die at'diiierent stages in o the operation ofthe press. p

Figured is a detail showing certain pin controlling camsand is taken along, the lined-4 of Figure 7, and v Figure 7 'isa view, partlyjin vertical section 5 and partly in elevation,- of portions of an exany. printed matter irregular edge It upon completion of the extru-. sion operation and, therefore, informing the fill-.- ish'ed container a small' section or annular band IQ will be removed, and the tube thustrimmed 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 15 and this end may then be sealed in any convenient way, as by simply folding and crimping the edges together in a. manner well known in'connection with ot er forms of -collaps'ible tubes. Any suitable a gn, such as designated il in Figure '1, may be appropriately applied to the surface of the wall It. This may include a base coating of any selected color and which-it may be desired to add: tothe tube for advertising purposes and by way of instructions. Methods well known in the .art,may be employed for the coating and printing operationa If the tube is to be used. for the packaging of llqi ors .or other potable or edible products, it is preferably formed of substantially pure tin.

However, the container, maybe made of other readily eiftrudable metals or combinations or al- I loys ofmetals suitable for use in connection with the particular substance to be packaged. v

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 siiitable quantity of liquor to constitute one drink is a tube havinga diameterof 1 inch and a,wa1l thick.- ness 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 ID was to provideja 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, however, should be extremely thin, i. e., say between .001 and .002 of an inch and preferably not more than about .0015 of an inch in wall thiclmess, in

orderthat it may be readily pierced by the thunfbnail for theremoval of the closure l2. It need the as short as possible so as to avoid unduly weakening the container. 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 [3 to only suflicient to allow insertion of the thumb-riaih While the diameter of the'closurel2 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 of a* pint of liquid. Obviously, the size of the container and the dimensionspf various portions of the container may be varied within relatively wide limits without departing from the general prin-:

ciples and scope of the invention. However, the

thickness and length of. the neck portion I3 is of considerable importance and should not be varied materially without regard to the considerations mentioned.

-Various manufacturing difficulties have been encountered in the production of the improved container. As previously stated, the container is primarily formed by an? extrusion operation 111- volving the use of a punch l8 and a die". .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 por-- tions having a direct bearing upon the present invention are shown herein. The die isprovfded with a recess 20-, which is of slightly greater diamv eter 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 end of the punch. The distance between 1 the corner 2| orpoint of largest diameter-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 effect of a variation in temperature and in part to variations in the metallurgical structure of the slugs perature 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 difliculty with which slugs may be extruded is afiectednot only by tem-- perature but to an even greater extent by variations in the grain and hardness of the slugs. It has been found that slugs ofidentically 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 28 at the lower end of the punch. The projection is of the appropriate. length and diameter to form the end closure l2 and neck ll of the tube while the shoulder 23 is of the appropriate form to produce the shoulder l l of the tube in cooperation with a slightly tapered bottom portion 24 of the die recess. The projection 22 of the punch maysuitably be formed sepabeing extruded. Relatively small changes in temrate from the main shank of the punch on a small position.

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 25, which is of only slightly greater diameter than the projection 22 The diflerence between the diameter of the passage 25 and that of the projection 22 will determine the 'wall thickness of the neck portion i3 of the tube. For the production of the typical tube described, therefore, this diflerence should 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, 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,

beonly briefly described here. They include a rod formed in several sections, .21, 28 and 29, the

latter two of which pass through an adjustabl sleeve 30. The'lower end of section 28 is adjustably connected with one end of a lever 3| mounted on theframe and having its other end connected with the lower endof a-vertically extending rod 32. This rod is surrounded by a spring 33 which; normally urges it downwardly. At its upper endthe rod is connected withan arm 35 secured to a pin 38 having also secured-thereto .a painof roller-carrying arms 30 and 31 whose rollers engage cams 38 and 39, respectively. These cams are secured to alshaft 4.0, which is a main drive shaft for the press and serves to operate the punchin the manner explained in said prior 6 I A...

Now, while the devices for controlling the p 26 are similar to those disclosed in my prior patent, nevertheless, for thepurpose of'successfully forming a container of the-type constituting a '10 part of the present invention, it is necessary to 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 con- 15 tainer, the cams 38 and 39 for controlling the pin 26 are so-cons'tructed and arranged that when the punch first engages the upper surface of the slug, thetopof the pin 26 will be held' either substantially flush with (the innermost edge of the die surface 24 or will be elevated slightly above this to engage the under surface of the slugl' 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 die bottom. The projection 22 will then penetrate the material of the slug and sijue'eze the metal aside until the section between the bottom ofthe projection'22 and the topof the pin 26 is substantially equal in thickness to the desired thickness of the closure 12. Should the top.'of the pin 26 be initially elevated into engagement with the bottom of the slug, it will be a permitted to drop under the pressure of the projection 22, exerted through the slug, until it is 35 substantially flush with the innermost edge of the surface 24. From this point the operation is the same as before, i. e., the .metal issqueezed with the pin held in this position until the closure portion l2 of the tube is produced in substantially .its final form; A part of thissqueezi'ng may take place simultaneously with the depression of the pin in this mode of operation. In the course of accomplishing this formation of the closure portion I2, the 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 Figure 4.

\ 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 is relatively small, being only length (if the neck l3. During this downward movement ofthe pin the metal to form the neck' l3 may'be'supplied in several ways. It may be partly supplied by the downward extrusion of some of the metal being squeezed between the shoulders. and 24, although due to the exces- -siv'e resistance to extrusion throughsuch a small passage it-is questionable whether much, if any, i of the metal is supplied in this way. Itis probeably supplied principally, ifnot entirely, by the drawing or nee action produced bythe downward movement of the closure portion I! of the tube in advance of. the projection 22. Ifdesii'ed, the downward movement of the pin 26 may take ward movement of the punch, or the downward movement of the pin may be arrested a trifle before the downward movement of the punch so thata slight, additional squeezing action takes place between the bottom of the punchfand' the trolling linkage. Should this spring be provided,

equal to the thickness of the closure 12 andthe.

place at a slightly slower rate than the down-' top of the pin. This, then, will provide a slight upward extrusion of a portion of the metal be-' tween these surfaces. v e 1 However, here again the resistance to extrusion through the slender. passage is so great that 5 it is not ,desirable'to attempt to extrude any substantial quantity of metal in thisway. My experiments have shown that it is not possible to completely form the neck" by the upward extrusion of metal squeezed from between the b0ttom of the projection 22 and the bottom of a solid die or.the top of a pin. that .is held stationary. The pressure required to extrude metal through such a narrow passage as to produce a neck having a wall thickness of about .0015 of an inch is 15 so great that either the punch or the die, or both, would break before a suflicient 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 become excessive if a slight outward taper to the passage is not provided. Accordingly, I form the, recess 20 with a very slight outwarditaper 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 'difliculty, or even impossibility,-of extruding from a relatively large passage such as that between projection 22 and pin 28, into the very thin passage between projection 22 and die 40 opening 25. J 'I'he control of the pin 26 may, if desired, be entirely through the cams 20 and 39, although the spring 33 is preferably included in the coriit will be understood that thepin 28 will be positively held by the cams. at a point with its top flush with the inner edge ofa shoulder 24 until the metal attains the proper thickness between this pin and projection 22. A drop may then be a provided on the cam to allow the pin '26 to be forced downwardly against the): action of the spring until the pin isdepress'ed to the extent required to form a neck I 3 ot ithejdesired length. 5

At this point further downward movement of the pin may be arrested by the coaction of positive stops, as explained in my prion patent, but at this time the downward movement of the pimch should also be substantially completed. Dueto so 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 lowerlimit for any particular set up of the mechanism.

As alsoexplained in myprior patent, the upward movement of the pin 28 should be delayed until the punch his been partially retracted so that a slight slippa e is? produced between the the punch. Thisallows for the easy removai of .the tube by the air hlast'means at the'appropriate time.

n connection with the fdi'maflon or the neck 15 n, it should be observed that thereis a fairly definite limit to the length of neck that can be' produced, As stated before, anattempt to ex-- trude 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 punch or die, or both. Moreover, an attempt to lengthen the neck by a drawing or necking oporation is apt to result in the fracture of the neck It) at some point, thus rendering the tube defective.

My experiments indicate that the maximum operation is completed.

2. A method of producing from a disc-like sluglength towhich the neck l3 may be safely extended when its thickness is not more than" .0015 of an inchis %of an inch. I

While a preferred method of and apparatus for producing a'special type of container have 7 been disclosed in considerable detail, it will be understood that various changes may be made in both the-apparatus 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 limitation.

What I claim is:

A 1. A method of producing a thin, metal, tubular, collapsible container which comprises forcing a punch against a slug in a die recess and commencing the upward extrusion of the tubular container while the entire die "bottom remains stationary until a portionof the slug attains'substantialiy the thickness desired for a corresponding portion of the container-and then permitting a corresponding portion of the die bottom to recede in unison with the punch the extrusion a thin, metal, tubular, collapsible container having an integral; readilyremovable closure which comprises forming the closure of the desired final thickness substantially within the body of the slug while simultaneously extruding a portion 01 a thin, metal, tubular, collapsible container having an integral, readily removable closure which comprises forming the closure of the desired final thlcknes while simultaneously extruding a por- ;tioh of the tubular side wall, and then forming a' thin neck between the under surface of the slug i eratlon.

4. A method of producing from a disc-like and the closure at least in part by a drawing opslug a'thin, metal, tubular, collapsible container having an integral, readily removable closure which comprises forming the'closure ofthe desired final thickness substantially within the body of the slug while simultaneously extruding aportion of the tubular side wall, and then forming a'thin neck between the bottom, of the sing and the closure by advancing the closure with the end of the punch'wlthout substantially modi.-'

the tubular side wall, and then drawing said closure away from the tubular body torfor'm a neck between them having a wall thickness of less than an extrudable dimension for the metal of said slug as it is being operated upon.

f .6. A method of producing a. thin, metal, tubular, collapsible container, having an integral, readily removable closure ,which comprises forcing a punch against a slugof extrudable metal in adie recess to form said closureof substantially.

its final thickness, and then forcing said closure away from the balance of said slugto form a neck between them having a wall thickness of lesssaid slug. as it is being operated upon;

, 7. A method of producing a thin metal, tubular, collapsible container having an integral, readily removable closure which comprises forcing a punch against a slug of extrudable metal in a die recess to form said closure of substantially its final thickness,and then "forcing said closure away from the balance of said slug to form a neck between them' having a wall thickness of less than 'an extrudable dimension for themetal of said slug as it is being operated upon while simultaneously extruding the metal along said punch toformrthe main tubular body.

a. A method of producing a thin, metal, tubular,;.collapsib1e container having an integral, readily removable closurewhlch comprises forcing a punch agalnst a slugof extrudable metal in a die recess while the entire bottom of said slug is supported to form said closure of substantialLv its final thickness, and then forcing said' closure away from the balanceof saidslug to form a neck betweeen them by causing a portion of the die bottom coincidingwith said closure to recede in advance of the pimch at the same rate as the latter. V I

9. In apparatus of the class described a die having a recess,- a punch adapted toenter said recess, said die "having a passage therethrmlgh sired thinness and then to provide for movement of said punch and pin in unison.

JOHN H .'FRJDEN. V

than an extrudable dimension for the metal of

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