US 674530 A
Description (OCR text may contain errors)
No. 674,530. Patented May 2|, I901.
SCREW CAP FOR CANS.
(Application filed July 16. 1900.
- UNITED STATES PATENT OF icE GEORGE WILOOX, OE LOS ANGELES, CALIFORNIA.
SCREW-CAP FOR CANS.
SPECIFICATION forming part of Letters Patent No. 674,530, dated May 21, 1901.
Application filed July 16, 1900. Serial No. 23,765. (No model.)
To all whom, it may concern:
Be it known that I, GEORGE WILOOX, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, haveinvented certain new and useful Improvements in Screw-Caps for Oans, of which the following is a specification.
Metal screw-caps for cans have heretofore been formed with depressions stamped in them for the reception of a knife-blade or screw-driver, whereby they may be turned for tightening or loosening. A cap has also been provided with two holes in its flat top and countersunk immediately therearound to receive headed pins, which project up above the surface in the form of lugs, be-
tween which a lead-pencil, knife, or other handy object may be applied as a lever to turn the cap. Both of these constructions lack in essential particulars, the first because the stamping or striking up of the metal is apt to weaken it at the angles and start crevices in the tinning through which the body may be attacked by the acid contents of the can, and the second on account of the liability to leak at the joints between the pins and the body and also on account of the pins working loose with usage.
To obviate these and other defects is the object of my present invention, which consists in spinning up the engaging lugs from the substance of the cap itself in the form of two conical or conoidal projections, all as hereinafter described and claimed.
In the drawings, Figure l is aperspective View of a screw-cap constructed according to my invention. Fig. 2 is a plan view of the cap, and Fig. 3 is a diametrical section vertically therethrough on a line bisecting both of the lugs.
Referring to said drawings, A is the screwcap, and a indicates the two upstanding lugs placed on a diameter therethrough. These lugs are of conoidal form and are spun up from the substance of the metal in such way as to be of practically uniform thickness and strength with the body. To this end the spinning-tool is first applied at a point a some distance removed from the base of the metal, and the spinning is continued from this point inward toward the apex, thus crowding sufficient metal into the lugs to substantially equalize their thickness with that of the body. Constructed in this way it is evident that the lugs will be seamless, of great strength, and without abrupt angles and that therewith the tinning or acid-resisting coating will be evenly spread over the whole surface without crack or crevice through which the corrodible backing may be attacked.
I claim- A metallic screw-cap for cans, having the upstanding lugs a spun up from an initial point a in the body removed from the base of said lugs, substantially as herein described.
GEORGE WILOOX. Witnesses:
G. G. JOHNSON, L. S. PORTER.