US3142280A

US3142280A - Container and method of forming the same

Info

Publication number: US3142280A
Application number: US129775A
Authority: US
Inventors: Heinle Carl William
Original assignee: American Can Co
Current assignee: Primerica Inc
Priority date: 1961-08-07
Filing date: 1961-08-07
Publication date: 1964-07-28
Anticipated expiration: 1981-07-28

Description

Filed Aug. 7, 1961 INVENTOR. KARL W/LL/AM ///1VE ATTOE/VE'Y 3,142,280 Patented July 28, 1964 3,142,280 CONTAINER AND METHOD OF FORMING THE SAME Carl William Heinle, Short Hills, N.J., assignor to American Can Company, New York, N.Y., a corporation of New Jersey Filed Aug. 7, 1961, Ser. No. 129,775 3 Claims. (Cl. 113121) The present invention relates to improvements in easyopening containers of the type wherein a single score line is formed in the cover skirt in order to provide a tearing strip which may be torn away to eliminate the locking connection between the cover and the container body and thereby permit removal of the cover.

Containers of this general type have been long known in the art but have never attained very great popularity. However, with the recent trend toward the use of aluminum in containers, interest in this general type of container has been revived because of the fact that when this container cover is made of aluminum, it may easily be torn along the score line manually without requiring the use of a key.

In the usual version of this container, the tearing strip is formed in the cover flange prior to the time the flange is crimped onto the container body. As a result, there is the definite danger that this preformed score line will crack during the seaming operation. The present invention contemplates a method of overcoming this problem by forming the score line during the seaming operation so that a preformed score is not required. As an additional feature, the invention contemplates a seaming operation wherein both the cover flange and the body wall immediately inwardly of it are simultaneously deformed to provide interlocking grooves which secure the cover in place on the body. This eliminates the need for providing the body with a locking groove prior to the seaming operation.

An object of the invention therefore is the provision of an improved method of forming an easy open tear strip container.

A further object is the provision of a method of forming a scored tear strip in the depending skirt of a cover during the seaming operation.

A still further object is the provision of a container formed by utilization of the instant method invention.

Referring to the drawings:

FIGURE 1 is a side elevational view of an easy-opening container formed according to the method of the instant invention;

FIG. 2 is a fragmentary vertical section on an enlarged scale taken through the upper portion of the container of FIG. 1 and showing the peripheral body and cover portions as they appear prior to the seaming operation;

FIG. 3 is a view on an enlarged scale of the upper portion of the container of FIG. 2 after the completion of the combined seaming and scoring operations, the view also showing in cross section a portion of the combined seaming and scoring roll and the seaming chuck which cooperate to perform the method steps of the instant invention;

FIG. 4 is a fragmentary section taken substantially along the line 4-4 of FIG. 3;

FIG. 5 is a vertical section similar to FIG. 3 but showing the invention as utilized in conjunction with a slightly different form of container construction.

As a preferred and exemplary embodiment of the instant invention, FIG. 1 discloses an easy opening container which has been formed by the method of the instant invention. The container includes a cylindrical tubular body which comprises a body wall 11 and a bottom end closure 12. The body wall 11 may be made of any suitable thin metal such as aluminum or tin plate and may be formed with or without a side seam. It may also be formed of fibre or plastic. If desired, the body 10 may comprise a one-piece drawn shell of metal or other suitable material.

The top end of the body 10 is closed by means of cover 14 which preferably is formed of an easily tearable metal such as aluminum, but which also may be formed of other suitable materials such as tin plate, etc.

As seen in FIG. 2, the upper end of the body wall 11 is initially curled outwardly and then extended downwardly to form an open hem 16 which is spaced outwardly from the main body wall 11.

The cover 14 is provided with a depressed countersink panel 17 which at its outer edge is bent upwardly to form a countersink wall 18 which is formed with a central step 20, a lower wall portion 22, and an upper wall portion 24, the wall portion 24 being somewhat larger in diameter than the wall portion 22. At its upper end the countersink wall 18 is curved outwardly and then downwardly to form a downwardly extending skirt or flange 26 which is spaced slightly away from the body hem 16 when the cover is inserted in the open mouth of the body 10 preparatory to the seaming operation, as seen in FIG. 2. If a hermetic seam is desired in the sealed container, the interior surface of the cover skirt 26 is lined with a thin film of a suitable resilient lining compound 28.

In carrying out the method steps of the instant invention, the cover 14 is positioned on the body 10, and a seaming chuck 36 is then inserted into the cover 14. The seaming chuck 36 is provided with an annular step 38 so that its lower and upper portions fit snugly against the

stepped walls

22, 24 of the cover 14. After the seaming chuck 36 has thus been positioned, the cover skirt 26 is rolled inwardly by the upper portion 49 of a circular seaming roll which is pressed into pressured contact against the skirt 26 in any suitable manner. As a result of the inward pressure exerted by the seaming roll R the upper portion of the cover skirt 26 is pressed against the body hem 16 and the latter is collapsed into engagement against the upper portion of the body wall 11 to form a closed hem as seen in FIG. 3. The lining compound 28 which is carried by the cover skirt 26 is compressed between the skirt 26 and the hem 16 to form a hermetic seal. Simultaneously with this collapsing operation, the lower portion of the cover skirt 26 and the inwardly adjacent portion of the body wall 11 are deformed inwardly into the annular space 30 which is disposed between the cover wall portion 22 and the body wall 11 by an outwardly extending annular bead or projection 42 which is formed in the lower portion 44 of the seaming roll R (see FIG. 3).

The rolling action of the head 42 produces an indentation or groove 46 in the cover skirt 26 and a cooperating indentation or groove 48 in the body wall 11. As a result of the locking action of these interfitting

grooves

46, 48, the cover 14 is firmly secured to the upper end of the container body. It will be obvious that this seaming method will also work effectively when the body 10 is formed of fibre or other soft stock, for in such case the cover head 46 will compress the material of the body wall and embed itself therein.

It has been found that a body wall 11 made of single thickness stock can be readily deformed by the seaming projection 42. In the event the body wall 11 is formed with a multi-layered side seam (not shown) which would be difficult to groove during the seaming operation, it may be desirable to pre-groove the side seam area in alignment with the subsequently rolled

grooves

46, 48 in order to insure that the

grooves

46, 48 extend across the side seam in the finished container.

In order to permit the easy removal of the cover 14 from the container body 10, a circumferential score line J 50 is rolled into the cover skirt 26 during the seaming operation in order to form the bottom, grooved portion of the skirt 26 into an easily removable tearing strip 52. The score line 50 is produced by a scoring roll 54 which is disposed between the upper and

lower portions

40, 44 of the seaming roll R. Preferably, the

parts

40, 44, 54 are separate pieces which are suitably secured together. The scoring roll 54 is provided with a sharp edge portion 56 which projects outwardly beyond the adjacent wall portion of the seaming roll R a distance which is somewhat less than the thickness of the cover skirt 26 so that the depth of the score line 50 is accurately controlled. The tearing strip 52 is provided with a depending tearing tongue 58 and a notch 60 which is disposed adjacent one end of the tongue 60. When removal of the cover is desired, the tearing tongue 58 is grasped between the thumb and forefinger of the consumer and is pulled or twisted diagonally upwardly, to the right as seen in FIG. 1. This twisting action results in a tear which extends across the tearing strip 52 from the apex of the notch 60 to the score line 50. Thereafter the tongue 58 is pulled circumferentially around the container thus detaching the tearing strip 52 from the cover 14 along the score line 50 and destroying the beaded interlocking connection between the cover 14 and the body wall 11. Thereafter, the cover may be readily lifted upwardly to remove it from the container body 10.

It is desirable to form the portion of the chuck 40 immediately below the scoring roll 54 with an annular band of narrow serrations 62, the apices of which extend outwardly to the edge of the scoring knife 52 and create knurlings 63 (see FIG. 1) in the cover flange 26 just below the score line 50. These knurlings 63 have the effect of work hardening the cover stock in this area and serve to confine the line of tear to the score line 50 and prevent it from tearing out of the score line 50 and down into the tear strip 52 during the opening operation.

FIG. 5 shows the instant invention as applied to a modified form of container wherein the upper edge of the body wall 11 is not hemmed, the cover skirt 26 is not provided with the sealing compound, and the knurlings 63 are omitted. However, in all other aspects, the closure of this modified form of container is similar to that of the preferred form of FIGURES 1 and 3, inasmuch as the cover skirt 26 is indented into the body wall 11 during the seaming operation to form cooperating

locking beads

46, 48 and a score line 50 is formed in the cover skirt 26 to create a tearing strip 52.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction, and

arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. The method of forming an easy opening container, comprising the steps of positioning a cover in the open end of a container body, said cover having a peripheral skirt extending over the marginal portion of said body adjacent said container end, rolling interlocking grooves in said cover skirt and said marginal body portion in a seaming operation to secure said cover and said body together, and simultaneously with said seaming operation rolling a circumferential score line in the outer surface of said cover skirt between said interlocking grooves and said container end to create in said cover skirt a removable tearing strip containing the grooved portion of said skirt to facilitate opening of said container.

2. The method of forming an easy opening container,'

comprising the steps of positioning a cover in the upper open end of a container body which is provided with an outwardly and downwardly turned open hem, said cover having a peripheral skirt extending downwardly from said container end, pressing said cover skirt inwardly against said open hem to collapse the latter into engagement with said body, rolling interlocking grooves in said cover skirt and said body below said hem to secure said cover and said body together, and simultaneously with the formation of said interlocking grooves rolling a circumferential score line in said cover skirt above said interlocking grooves to create in said cover skirt a removable tearing strip to facilitate opening of said container.

3. The method of claim 2 wherein a narrow annular band of knurlings is formed in said cover skirt immediately below said score line simultaneously with the formation of said score line and said interlocking grooves.

References Cited in the file of this patent UNITED STATES PATENTS 1,689,605 Walter Oct. 30, 1928 1,741,918 Burbank Dec. 31, 1929 1,821,157 Hothersall Sept. 1, 1931 2,072,149 Young Mar. 2, 1937 2,159,325 Fabrice a May 23, 1939 2,351,550 Sebell June 13, 1944 2,443,185 Erb June 15, 1948 2,521,098 Sebell Sept. 5, 1950 2,902,075 Gray Sept. 1, 1959 FOREIGN PATENTS 60,656 Norway Apr. 3, 1939 261,793 Switzerland Sept. 1, 1949