US2750070A - Keys for canning tins - Google Patents

Description

June 1956 P. A. FOLEY KEYS FOR CANNING TINS Filed Oct. 26. 1954 INVENTOR Philip A. Foley.

BY W f ATTORNEY ilnited States Patent KEYS FOR CANNING TINS Philip A. Foley, Kittery, Maine Application October 26, 1954, Serial No. 464,810

Claims. (Cl. 22052) This invention relates to improvements in keys for opening vacuum pack canning tins, and the like, and, more particularly, to keys incorporating flat guide strips bendable to receive tear-strips, or so-called lift strips, from cans, as the strips are removed in opening the cans.

A major difiiculty encountered with conventional removal keys is the tendency of the tear-strip reel or coil, as wound up on the key, to be axially displaced, and slip to one side or the other. Sometimes the coil has to be unwound and rereeled. Cuts frequently occur as a result of contact with axially displaced, sharp exposed edges of the winding band.

To overcome these difficulties, it has been proposed to provide specially formed keys incorporating guide sections for the reeled-up tear-strip. Other proposals include the use of separate guide attachments for the conjoint reception of a conventional key and the coiled-up tear-strip, as reeled off a can. In all these prior art devices, expensive sets of dies and forming equipment are required, with the result that the cost of the individual keys and auxiliary items is unduly high and uneconomical in the tonnage lots normally required.

I have now found that conventional keys can be modified, at slight cost, and in a most practical manner, to incorporate guide means for tear-strips, and yet retain the generally flat-against-the-can position normally assumed by keys spot-welded to cans, the keys being formed with a weakened stem portion to facilitate its removal from the can, when the can is to be opened by coiling up a tear-strip on the key. By the improvements of the present invention, a flat, bendable guide strip, suitably slotted, is welded, or otherwise fixedly secured on and over the slotted portion of a conventional key. With the guide strip lying flat on the shank, at the start of the can-opening operation, the free end, or starting tab of the tear-strip of a can is threaded through the key slot, and two full turns of the key are desirably made, before bending up the free ends of the guide strip to form a guideway for the tear-strip. Under these conditions, the key is directly opposed to the can, and a maximum gripping of the tear-strip is secured, resulting in an increase in the pressure available to break the seal of the tear-strip.

When the initial turns of the key have been made, both ends of the bendable guide strip are turned up, at right angles to the key, to form a reel or frame for receiving the tear-strip, and the key is wound on itself until the tear or binding strip is removed from the can. The center section of the guide strip, as noted, is welded to the shank of a key, and the bendable ends can be rounded or indented, so as to prevent injury to the user, and also to make possible a firm grip. With the guide strip lying fiat on a key, and the key welded onto a can, there are no projects or protuberances on a can, particularly if it is of the vacuum-pack type with a rolled or beaded sealing rim The size of the opening in the key for receiving the starting tab, the key, and the lift guide, or guide strip,

ice

may be varied, as desired, to adapt the novel key combination herein for any particular use.

It is, therefore, among the objects of the present invention to provide improved key means for removing tear or lift strips from vacuum-pack tins, or the like.

It is another object of the invention to provide a key which will insure the complete removal of a tearable sealing strip from a can Without any danger of the spiral winding slipping axially off the end of a key.

A further object of the invention is to provide a key embodying a deformable flat guide strip adapted to be bent to form a rail or guide to control a tear or sealing strip as it is removed from a can, whereby the strip may be removed without becoming fouled up, and without danger of cutting the person removing the strip.

The above and other desirable objectsand advantages of the present invention will be more readily appreciated by reference to the specification and attached drawings, which disclose a preferred embodiment of the invention, which is shown by way of illustration only, as it is not intended to be limited to the form shown, except as such limitations are clearly imposed by the appended claims.

In the drawings, like numerals refer to the similar parts throughout the several views, of which Figure l is a side elevation of a vacuum can with a key in the act of winding the tear strip thereon;

Figs. 2 and 3 are a plan view and a side elevation, respectively, of the novel composite key herein;

Fig. 4 is a view similar to Fig. 3, showing the ends of the guide strip raised in tear strip-guiding and -receiving position;

Fig. 5 is a section taken on line 55 of Fig. 4, and

Fig. 6 is a view similar to Fig. 5, showing a wound-up tear-strip on a key.

Turning now to the drawings, there is shown in Fig. l, a vacuum-pack can 1, having a beaded lid 2, a tear-strip 3, integral with the cover and can and adapted to be severed or torn from its attachment to the can along spaced lines of weakness 4, 5, formed on the sides thereof. The tear-strip has a starting tab or free end 6, having a rounded tip 7, the end being conformed to the can and lying snugly thereagainst.

The tearing strip can be of any suitable width, depending on the size and type of can used. As noted, the tearstrip may be formed by spaced lines of weakness in the cover, or a separate strip may be soldered in place. When the tear-strip is to be removed, its free end 6 is bent outwardly from the can, and is threaded into the slot in the novel key shown in Figs. 35.

The key 10, as shown, is formed of a single piece of stiff wire having a shank 11, and is bent on itself at one end to form a flat butterfly grip'lZ. The free end of the shank 11 is flattened, in the plane of the grip 12, as indicated at 13, and the flattened end is punched, or otherwise slotted to form a narrow slot 14, adapted to freely receive the tab end 6 of the tear-strip. Up to this point, the key and tear-strip combination is conventional and well known in the art.

The improvement of the present invention forming the feature of novelty thereof, is a bendable, flat metal strip 15, desirably formed with rounded ends 16, 17, and having a central section 18, welded or otherwise fixedly secured to and made integral with the flattened end of the key. The section 18 is slotted, as indicated at 19, to register with slot 14 in the key. If desired, a single slot may be formed in the composite key, after the guide strip has been aflixed. The flattened end 13, may be extended, in the usual manner, and provided with a transverse indentation or line of weakness, whereby when the novel key is spot welded on to a can at the elongated portion of the key, it may be broken off readily when the can is to be opened. The improved guide strip 15 may be aiiixed to the key before the latter is secured in place on a cat, or the key and guide strip can be simultaneously secured together, and the key onto the can, by a single spot-welding operation. While spot Welding is the preferred method of joining the key parts, it will be understood that the parts may be soldered together any suitable manner.

The operation of the device herein is simple and ethcient. When the can is to be opened, the key is detached from the can, the tab end 6 of the tear-strip 3 is bent up, and the compound slotted key is fitted on and over tab end 7. To insure optimum operation, the slotted key 10 is desirably given two full turns, whereby the free end of the coiling tear strip is secured and the tear strip is started and torn from the can. The direct apposition of the .key to the can permits of a maximum starting tearing effort. By making two complete turns of the key, the tear strip starts to coil tightly on the key. At this point, the lugs or free ends 16, 17, of guide strip are bent up from the key, and form a reel or annular guide channel with section 18 to receiving the remaining turns of the wound up tear strip. The tear strip is Wound up as a flat coil, as shown in Fig. 6, with the turns firmly held and restrained from any undesired axial displacement or movement.

While the preferred mode of operation is indicated above, it will be understood that the lugs 16, 17 of the guide strip may be bent up before the key is fitted on and over the free end of the tear strip.

There has been described and illustrated a device capable of performing all of the specifically mentioned objccts of this invention, as well as others which are appareat to those skilled in the art. Various uses of the present invention may be made employing the described structure. Accordingly, it is apparent that variations as to operation, size and shape, and rearrangement of elements may be made without departing from the spirit of the invention. Accordingly, limitation is sought only in accordance with the scope of the following claims.

Having thus described my invention, What is claimed 1. A key for removing a tear strip from a can comprising a strand of stilt Wire bent on itself to form a bandle at one end, and flattened at the other end; a flat bendable strip apposed to the flattened end of the key, whereby the ends of the strip can be bent up to .define a tear-strip guide therebetween; and a tear-strip receiving .slot in the flattened end of the key and the apposed guide strip.

2. A tear strip-removing key according to claim 1, characterized by the fact that apposed guide strip is autogenously bonded to the key.

3. A tear strip-removing key according to claim 1, characterized by the fact that the apposed guide strip is integrally joined to the key.

4. A tear strip-removing key according to claim 3, characterized by the fact that the apposed guide strip is antogenously joined to the key.

5. A tear strip-removing key according to claim 4, characterized by the fact that thc apposed guide strip is spotwclded to the key.

6. A tear strip-receiving and guiding key for use in opening vacuum-pack cans, comprising a slotted key and a fiat, bendable guide strip on the key, the ends of said strip being bendable into substantially U-shaped form to form a tear strip-receiving guide.

7. A device of the character described, comprising a can opener key and a fiat, bendable strip on the key, said strip welded to said key to define a central section rigid with the key, and end sections bendable to form a tear strip guide therebetween, and a tear strip-receiving slot in the said central section of the guide strip and the apposed section of the key.

8. The combination of a vacuum-pack can, a tear strip incorporated in the can and having a key-engaging extension; a key detachably secured on the can; and a fiat, bendable guide strip integral with the key at the guide strips central section and bendable at both ends, whereby the tear strip is axially constrained on the key when the guide tabs are bent up and the key is fitted over the free end of the tear strip and is rotated to coil up the tear strip as it is removed from the can.

9. A tear strip-receiving and guiding key of high mechanical advantage for use in rapidly opening vacuumpack cans, comprising a slotted key and a bendable guide strip attached intermediate its ends to the key, the free .nnattachable ends of such strip being bendable to form a tear strip-receiving guide.

10. A device of the character described, comprising a can opener key mounting a bendable guide strip, said device being slotted to receive the starting tab of a tear strip of a can, said guide strip ends being bendable to define parallel guides positioned substantially normal to the plane of the key to define parallel safety guides for the ragged edges of the severed tear strip whereby increased mechanical advantage of the key and accelerated severance of the tear strip and contemporaneously the tear strip is safely axially constrained on the key as it is wound up and removed from the can.

References Cited in the tile of this patent UNITED STATES PATENT 172,759 Mentzel Jan. 25, 1876 510,787 Harris Dec. 12, 1893 516,189 Dixon Mar. 13, 1894 753,976 Goss Mar. 8, 1904 2,326,191 Zabler Aug. 10, 1943 2,552,961 Grossenbach May 15, 1951 2,649,990 Lyle Aug. 25, 1953

Images