Improvements in Sheet Metal Cans.
Year: 1898

page_text: Date of Application, 11th Jan., 1898-Accepted, 16th Apr., 1898
COMPLETE SPECIFICATION.
Improvements in Sheet Metal Cans.
I, JOSHUA ENTWISLE, of the Firm of E. K. Dutton & Co., of 5, John Dalton
Street, Manchester, in the County of Lancaster, Fellow of the Institute of Chartered
Patent Agents, do hereby declare the nature of this invention (communicated to
me from abroad by Olin Stephen Fellows, of Middletown, Orange County and State
of New York, United States of America, General Manager,) and in what manner
the same is to be performed to be particularly described and ascertained in and by
the following statement and accompanying drawings :-
:―
My invention relates to a sheet metal can designed to be opened by the removal
of a strip or zone by means of a strip-winding key. The object of my invention is
to provide means to sustain the strip-winding key during the stripping operation
against movement longitudinally on its longitudinal axis, and to thereby render the
stripping operation more safe convenient and accurate than heretofore.
As it is practically impossible under the conditions heretofore existing to rotate
the key on its longitudinal axis, to wind off the stripping zone of the can, without
moving the key more or less longitudinally also, it has required considerable skill
and care to effect the removal of a strip evenly, any considerable deviation in
alignment rendering the operation difficult and even dangerous to the fingers of the
operator. It will readily be seen that if the fingers of the operator are relieved of
the task of trying to maintain the position of the key longitudinally while rotating
the same the operation can be performed with less exertion, the energy being all
applied to the best advantage in effecting the severance of the metal along the
prescribed line, and a perfectly smooth, even winding of the strip being attained,
having no protruding sharp or ragged edges to endanger the fingers of the operator.
This I accomplish by my present invention which consists in forming the can
with a supporting surface for the end of a key of prescribed length at right angles
to the stripping portion, said rectangular supporting surface acting both as a gauge
and as a means of meeting pressure applied longitudinally and diverting it to aid in
the severance and winding of the strip.
My improvement may be applied to cans in which the stripping section consists
of either an inner or outer flange of an end plate; or of a portion of the can body
itself; the essential feature being a rectangular supporting surface at or below the
line of severance,-the strip-winding key being of corresponding length and
forming a feature of the invention in combination with a can of my special con-
struction.
In the accompanying drawings,
Figure 1, is an end elevation of a portion of a can in which the stripping portion
consists of an inside flange on the end plate, the stripping tongue being shown as
formed in one piece with the flange;
Figure 2, is a sectional elevation of the same structure;
Figure 3, a similar view showing the stripping tongue bent upward for engage-
ment with the strip-winding key;
Figure 4, a similar view illustrating the stripping operation;
11hon illustrating the strinning oneration.

page_text: Figure 6, a sectional elevation of one end of a can of slightly modified form;
Figure 7, a sectional detail illustrating the stripping operation on such a can;
Figure 8, a sectional elevation of one end of a can in which the outer flange of
the end plate constitutes the stripping portion ;
Figure 9, a sectional detail showing a structure in which the stripping portion
and the rectangular key-supporting surface are formed on the can body;
Figure 10, is an elevation of the strip-winding key.
It is to be understood that where I herein refer to key-supporting surface at right
angles to the stripping portion of the can, I mean a key-supporting surface at sub-
stantially right angles to the stripping portion, since any slight variation from a
right angle, though not so effective, would answer the same purpose in a measure.
A, represents the body of a sheet metal can, and B, one of its end plates. The
stripping portion s, which is to be removed to open the can by the release of the
end plate B, may consist of an interior flange of the end plate, as in the first seven
figures of the drawings; of an exterior flange of the end plate as in Figure 8; or
of a portion of the can body A, as indicated in Figure 9. In either case the adjoin-
ing part of the end plate or can body is formed with the key rest or bearing r,
extending at right angles to the width of the stripping portion
S.
The stripping portion is preferably weakened at the desired line of severance by
an incision, or other reduction in thickness, coinciding with or parallel to the
key rest or bearing surface r, and it is provided with a tongue t, for engagement
with the slot k¹, in the strip-winding key K.
The distance between the slot k¹, and the lower end k, of the key K, is such that
when the key K, is in engagement with the tongue and strip its lower end k, will
rest against the surface of the rest or bearing r.
As the strip s, and the rectangular surface r, are parallel it follows that the
bearing of the end k, against the surface r, insures perfect alignment during the
stripping operation, since the natural tendency of the operator to press downward
on the key will insure its continued contact with the rest ŕ.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is:
-
1. A sheet metal can formed with a stripping portion adapted to be removed by
means of a strip-winding key, and with a supporting surface for the said key at
right angles to said stripping portion, for the purpose and substantially in the
manner described.
2. A sheet metal can provided with a metallic stripping portion adapted to be
removed by means of a strip-winding key and with a flat supporting surface for
said key contiguous and at right angles to said stripping portion, substantially as
described.
3. A sheet metal can provided with a metallic stripping portion adapted to be
removed by means of a strip winding key, and with a supporting surface for said
key at right angles to the said stripping portion, substantially as described.
Dated this 10th day of January 1898