IMPROVEMENTS IN SHEET-METAL CANS, CASES, OR BOXES FOR PRESERVING FOOD AND OTHER PERISH- ABLE SUBSTANCES
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Frank Kingston at the Office of
the Commissioners of Patents on the 16th April 1878.
FRANK KINGSTON, of Greenwich, in the County of Kent.
"IMPROVEMENTS IN
SHEET-METAL CANS, CASES, OR BOXES FOR PRESERVING FOOD AND OTHER PERISH-
ABLE SUBSTANCES."
My Invention relates to improvements in cans, cases, or boxes for containing
preserved meat, fish, fruit, vegetables, and other articles of food and similarly
perishable substances.
The object of the said Invention is to furnish sheet-metal cans, cases, or boxes
which, while as strong and securely fastened and made air-tight as the ordinary tin
cans, cases, or boxes used for the above purposes, shall be free from the difficulty,
inconvenience, and danger heretofore experienced in opening such vessels.
It is well known that the only method of opening them in common use is that
of cutting the metal with an implement provided with a strong blade or knife, in
which operation great force has to be exerted, and the utmost care has to be exer-
cised to avoid injuring the hand with the said implement or with the ragged edges
of the metal, and also to avoid spilling the syrup, oil, juice, or other liquid contents
of such vessels.
I am aware that various contrivances have been suggested for avoiding these
inconveniences and to provide an efficient method of securing and hermetically
scaling these vessels in such a manner as to permit them to be easily and conve-
niently opened; but at present none of these contrivances have proved successful
to such a degree as to cause their introduction into common and general use.
by my Invention I provide means whereby I can securely close and hermetically
seal a sheet-metal can, case, or box in such a manner that it will remain perfectly
sound and air-tight for any desired length of time, and can be opened without a
knife or other implement.
But
In practising my Invention I take or construct a tin or other sheet-metal can,
case, or box, either round, square, or of any other shape, and fit a lid or cover on
the same in the ordinary manner. Then I place around or over the rim of the
[frive 2α.]

page_text: cover and the adjacent surface of the can, case, or box a band or strip of paper,
parchment, skin, india-rubber, or other like material, and affix the same to the can
or box and its cover by cement, varnish, glue, or otherwise, in such a manner that
it closes the seam or joint between the box and cover. Then I place over or
around this paper or other band or strip a band or strip of tin or other metal,
slightly wider than the said band of paper or other material. This metal band
will therefore overlap the paper at both edges, and these overlapping portions or
edges are soldered, one to the cover, and the other to the adjacent suface of the can,
case, or box. I prefer to make this metal band of such a length than when sol-
dered on the box, one end will extend over or overlap the other end. And this
outer end may be diminished in width and formed with a loop or eye to facilitate
its removal.
When it is desired to open the can, case, or box, this outer end of the metal band
or strip is detached or pulled away from the cover, and then with very slight force
the entire band or strip may be pulled or peeled off of the box and cover, the slight
extent or area of the soldered surface permitting this easy detachment or removal
of the said band or strip.
The cover or lid of the can or box may then be taken off like that of an ordinary
box or case.
And one very important feature of my Invention is the opening of
these cans or boxes without destroying or injuring them or their covers, so that the
same box and cover may be repeatedly used.
According to a modification of my said Invention I secure and hermetically seal
a sheet-metal can, case, or box, as follows, that is to say, I make the mouth or part
to which the cover is to be applied taper or conical, and I form the cover with a
conical or taper surface; I place around this conical surface of the cover a band or
ring of india-rubber, and then insert the cover in the taper mouth or aperture of
the can or box. When the vacuum or partial vacuum is produced in the same in
the ordinary manner the external pressure will force and keep the said cover tightly
in place.
I may form on the said cover or stopper small lugs or ears which project
over the sides of the case or box, and assist in keeping the cover in place in
.the same.