Improvements in and relating to Jars for Preserving Fruit and other Substances.
Year: 1897

page_text: Date of Application, 20th Apr., 1897-Accepted, 22nd May, 1897
COMPLETE SPECIFICATION.
Improvements in and relating to Jars for Preserving Fruit and other
Substances.
I, KATHERINE ELLMAKER GUNKLE, Spinster, residing on The State Road,
Hamlet of Frazer, in the County of Chester and State of Pennsylvania, United
States of America, Agriculturist, do hereby declare the nature of this invention,
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The object of this invention is to furnish a jar for fruit, preserved vegetable
matter and for other uses, which may be readily sealed in an air-tight manner, and
which, also, may be readily unsealed or opened.
In carrying out my invention, I have endeavoured to compensate for variations
in the mouth of the jar incident to the production of blown or molded glass jars,
by making such mouth with a very slight taper and by making the flange or skirt
of the cover almost straight, that is to say, essentially cylindrical, so that a cover
fitted to such mouth, with a yielding gasket between, may extend down about such
mouth to a greater or less extent, according as the variation is less or more, and
yet be air-tight. The gasket is designed to extend beyond, that is to say, below
the cover so as to be accessible for unsealing the jar. The cover may be enameled.
The jar is adapted to be sealed by the combined action of the internal rarefied air
and external atmospheric pressure.
Having thus set forth in a general way the principle of my invention, I will
proceed now to describe the best mode in which have contemplated applying that
principle, and then will particularly point out and distinctly claim the part,
improvement or combination which I claim as my invention.
In the accompanying drawings illustrating my invention, in the several figures
of which like parts are similarly designated, Figure 1 is an elevation with the
parts disassembled. Figure 2 is sectional elevation, greatly exaggerated, of the
mouth end of the jar, with the cover in position, as the same will be when the jar
is sealed.
The body a of the jar may be of glass, and of any approved form, but I prefer
to make the mouth of the jar as large as permissible, so as to facilitate the filling
and emptying of the jar. The mouth 6 is divided from the jar by a very slight
shoulder c, and it is provided with a slight bead or lip d, which, in conjunction with
the shoulder forms a groove or cavity e for the reception of a gasket or other
suitable packing ring f. For purposes presently appearing, I prefer to give a
Elight taper or curve to this surface of the mouth of the jar.
The gasket f may be a flat tube or ring of rubber, which is held upon the mouth
of the jar and within the groove e thereof, by means of its own elasticity, and in a
vertical position, as shown.
The cover g is made of metal, preferably sheet metal stamped to shape, by
means of dies, so as to insure practical uniformity in their production. The
flange or skirt 9 of the cover is nearly straight, that is to say, it is essentially
cylindrical, although the drawing shows it curved the better to delineate its
conformation.
As is well known, in the production of blown glass jars in molds, there is more
or less hot air or gas trapped in the mold, which not being expelled produces a
cushion which prevents the glass from entirely filling the mold, and the result is
that in the manufacture of jars from a single mold there will be considerable
variation in their size, and this variation is so great, that covers designed to fit a

page_text: jar of a given size will be found too large for some, and hence it is impossible to
seal with such covers in such manner as to make the jars air-tight. Now, by
the provision of the externally tapered mouth with its packing and a cover having
its flange or skirt practically straight or cylindrical, it will be seen that a cover
designed for a jar of the full size, and to fit down upon the mouth of such jar
substantially to the extent shown in Figure 2, or even higher up upon the mouth
of the jar, may be fitted to the jars of the same size whose mouths are of less.
diameter, it being necessary simply to crowd down the cover further upon the
mouth.
In using the jar, it is filled with the hot substance, the gasket f having first
been applied, and then the cover is pressed down over the gasket until it meets
with sufficient resistance to be held in place. The hot air or gas trapped within
the jar, upon cooling, exerts a sort of suction upon the cover, which, aided by
external atmospheric pressure, insures the air-tight sealing of the jar.
In order to unseal the jar it is well to catch hold of the projecting edge of the
gasket and pull it down from under the cover, so as to admit air beneath the cover,
when the cover may be readily displaced; and this operation may be greatly
expedited by heating the metal cover, the cover becoming hot and thus expanding
more rapidly than the glass. And this fact of the difference in expansion between
glass and metal, affords an additional reason why I prefer to use a metal cover on
a glass jar.
Jar covers have been made heretofore with porcelain and other linings of non-
oxidizable character, and while I may so line my cover, I prefer, for economical
and other reasons, to enamel the cover in accordance with the well known processes
of enamelling sheet metal, particularly iron.
The cover may be provided with a lug h in order to afford a finger hold upon,
the cover to aid in applying and removing it.
am
I am aware that glass jars have been provided with glass covers, secured to the
jar through the intervention of a rubber gasket, and I am also aware that glass
vessels have been supplied with metal covers forced upon their mouths; and I
also aware that a glass vessel has been provided with a tapering and grooved neck
supplied with a rubber gasket and having a tapering metal cover forced thereon
and held frictionally by the rubber gasket. My invention differs from all these in
that I use a metal cover having an essentially straight, that is to say, cylindrical
skirt or flange in combination with a flat gasket immovably fixed to the mouth of
the jar, and a jar whose mouth is slightly curved and tapering.
The cap or cover may be lined with cotton, for purposes of making it air-tight,
and therefore microbe proof; such a lining having the additional advantage of
being inexpensive.
Instead of a rubber gasket I may use a gasket of felt.
The invention is not limited to the kind of lining or to the kind of gasket.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what
I claim, is :-
As an improved article of manufacture, the herein-described jar having its mouth
of essentially the diameter of the body of the jar and with a slightly curved taper
externally, and provided with a flat circumferential gasket applied vertically to
said tapered portion of the mouth, combined with a metal cover having its skirt or
flange essentially cylindrical, whereby said cover is adapted to be applied to the
gasket upon the mouth of the jar whether the jar's mouth be of the exact size of
the cover or not, substantially as described.
Dated this 20th Jan of
1007
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.