US1615930A - Can and method of forming - Google Patents

Description

Patented Feb. l, 1,927.

UNITED STATES PATENT OFFICE.

WILFRED E. BURNS, OF BURLINGAME, CALIFORNIA, ASSIGNOR TO M. J. B. CO., F` SAN FRANCISCO, CALIFORNIA, A CORPORATION 0F DELAWARE.

CAN AND METHOD OF FORMING.

Application Med August 4, 1926. Serial No. 126,957.

This invention relates to the manufacture of tin cans as used for preserving foods and other perishable material, and particularly to specific can construction through whlc a can is provided with a tearing strip so arranged that the lid of the can may of service on the can after the tearing strip is removed.

The principal objects of the invention are to provide an improved manner of forming such cans and overcoming some of the manufacturing difficulties heretofore encountered so as to make this type of can cheap and practicable for the common use to which cans are generally put.

Other objects and advantages of my construction will appear in the following description.

In the drawings hereto Figure 1 is an elevation of a finished can in accordance with my invention and having the upper portion broken away to reveal the inner relation of the layers of metal at the upper portion where the invention particularly resides.

Figure 1A shows in section the layers of metal as in Figure 1 but with a slight modification of the lid of the can.

Figure 2 is a fragmentary portion of the upper portion of the can adjacent the vertical seam after the tearing strips has been removed.

Figure 3 shows the upper portion of the blank from which the can body is formed. Figure 4 shows the folding of the upper margin of the blank before formin the body. Figure 5 is an edfre view of Flgure 4 and Figure 6 is a similar view after the folded blank has been rolled or pressed to bring the outer surfaces of the body flush or in line so that the outer diameter will' he of uniform diameter when the tubular body is formed from the folded blank.

Brieiy a can with a tearin which when torn od the can and in place thereon. Through described, In invention provides s rip at its upper end slight modification of the lid and position In the drawings 1 designates the tubular shell or can body vertically seamed at 2 and leaves a lid fitting on` provided with a bottom 3 flanged, soldered, or otherwise secured thereto in the known manner.

At the upper portion of the can the thickness of metal shown in section has been much exaggerated to more clearly indicate the relation of the parts and from which it will be seen that the bod. is reversely folded twice to form a band o triple thickness from the line 4 to the line 5. Above the line 5 the body is outwardly flanged and inter-lockedat 6 with a lid member 7 in the known manner and ma incorporate soldering or any of the pac in or sealing materials as commonly used in t ese joints as may be desired, all depending on he particular use to which the can will e ut.

round the inner surface of the outer layer 1 of the triple layers of the can body are scored lines 8 and 9 terminating in a freely extending strip 10 adapted for engagement with a key for tearin off in the known manner, and `when torn o will leave lid 7 with a neck ext-ending down to the upper score line 9 telescoping over the upper end ofv the can of reduced diameter. The

depth of the telescoping neck may of course be arranged to suit any requirement by suitable pos1t1onin of the'score lines in comblnation with tie depth of the triple layer of metal. Also it should be noted, this upperlend of the can over which the lid telescopes is of doubled metal with a rounded smooth upper edge at 1l.

If the vertical seam 2 has been soldered the lid will not be free for accidental removal after tearing off the strip but will be held in place by a slight area of solder 12 which extends up under the depending neck of the lid, but which is easily broken by first lifting the lid from an opposite point.

If a can with an internal friction lid is desired, it is simply necessary to elevate the score lines to the points 8 and 9 so as to bring the upper one close to the upper crimped edo'e of thecan, and to depress the top of the hdto the position 7 all as shown in Figure 1^, and through which slight variations the tearing ofi' of the strip leaves a lid tightly fitting the interior, the depth or angle of the internal extension ofthe lid being arranged to suit the requirements.

In case of either type ofl lid it will be body noticed that uit lid is substantially in thtsame position after tearing off the strip as it was before and therefore has no tendency to force out a lot of liquid from well lled cans as would a lid whiclr assumed aconside'rably lower position.

In making my can the upper end of the l blank is cut to the sha e shown in Figure 3, scored on the far si e at 8 `and 9 and folded away from the observer along the line 13, and toward the observer along the line 14 as indicated in Fi re 4 so as to form respectivelythe ben 4 and 5.

This folding is done onfa folder or by passage through rolls before Vmakin the tubular body, and would through or mary folding operations result in the upper layers of metal extending forwardly from the outer surface l'of the nal can body, but preferably before 'forming' into a tubular body the upper triple layers of metal are forced back by any suitable means'to the position shown in Figure 6 so as to make the outer surface of the outer layer 1 Hush with the outer surface of the can body.

This operation may of eoursebe done at the time of forming the tubular body if desired. v

Vertical extensions 15 and 16 are provided and reversely hooked as indicated in Figure 4 for forming the common lock seam 2 from the line 4 down to the bottom of the can.

The bevel portions 17 and 18 form when folded a bevel abutting joint with the re-y versely beveled portions 19-20 lying interv mediate an inner overlapping wall 21 portion and an outer overlapping wall portion 22, and above which abutting bevel joint the outer wall portions 22 simply overlaps the inner wall portion 21.

After forming the tubular body of the can with the joints and portions in the relations described the body is passed over a soldering roll and soldered from end to end along the line of the seam 2 and after which the tube thus formed is outwardly flanged at the ends and the heads secured thereto in the known manner.

I am aware of attempts to produce the' type of can 'described by rst forming a tubular body with a lock seam extendingfrom end to endv and then by means of rolls forcibly working a ring of the metal inwardly and upwardly within the tubular body, but it is to overcome the great difficulties of such operations, especially in passing over the seam, and the injurious cracking of the metal and scaling of the tin coating 'therefrom that'I have devised my 60 special blank avoiding the lock seam at the point of the folds, yet providing an overla J of the ends of the body wall above theloc seam, and by my I have eliminated all injury to the metal and made it possible to determine with aecuracy the depth of'the folds and overlap or fit' of the li It is of course obvious without further method of first formingv the folds before forming the tubular body illustration that my invention as described' for round cans, may alsof be applied to cans other`than round if desired and the terms of my appended claims are to be construed as covermgx such other shapes to Whicl` the invention may be applied.

I claim:

1. A can of the character described havl ing a body wall formed of 4a single thickness of metal for the major part and a band of triple layer thickness at the upper end, said body Wall being joined by a lock seam from said band to the lower endof the can only and the inner and outer members of said triple layer being in simple `overlapping relation at the joint.

2. A can of the character described having a body wall formed of a single thickness of metal for the major part and a band of triple layer thickness at the upper end, said :1-

body wall being joined by a lock seam from said band to the lower end of the can only and the inner and outer members of said triple' layer being in simple overlapping -relation at the joint with the intermediate layers abutting at their ends.'

3. A. -can of the character described havt ing a body wall formed of a single thickness of metal for the majo-r part and a band of triple llayer thicknes at the upper end. said body wall being joined by a lock seam from said band to the lower end of the can only and the inner and outer members of said triple layer being in simple overlapping relation at .the joint with the intern'iediate layers abutting at their ends at a line extending at an angle to said seam.

4. In a can of the character described a plurality of layersof metal forming the side wall at one end thereof, a tearing strip circumferentially Aformed around the 'outermost of said layers arranged to release upon removal an end lid fitting said can, said lid being held against accidental displacement by a localized soldered area adapted for breaking by lifting the opposite edge of ICO lll-5

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