Year: 1885

page_text: of manufacture. The mode of spinning these cups is as follows: I place a sheet of
tin of the requisite size in one or more metal frames B in the following manner:
A frame B is made ef angle tin, with a lid of the same construction but made to
fit over the frame B and hinged at one end. Some of these frames B are made
one fifth longer and two-thirds wider than the tin plate A in which it is intended
to spin the cups. I place in this frame B a sheet of tin A of the requisite size
between the frame B and the lid, and secure it by shutting the lid and holding it
closed in this position by a spring catch or other suitable device. To prevent the
tin-plates from moving I fill up the spaces not occupied in the said frames B at one
end with a piece of tin plate of corresponding size to the vacant space fitted with
a double edge, so as to grip the tin plate intended for spinning; and the sheet of
tin A about to be spun and the spare piece with double edge then occupy the whole
length of the frame B. above described. This is done so that the sheet of tin A.
which is being spun may be shifted in the frame B as required so as to bring each
row of cups over the centre of the metal chuck C hereafter described. In this
case the spare piece of tin with the double edge is moved in like manner to fill up
the spaces in the frame B where required. In the centre of such frame B or at
such other point as is required I attach a metal chuck C with four arms or stays
which are bolted securely to the stays on the frame B as shown in the drawings.
The chuck C being screwed on the spindle of the lathe and being revolved at the
rate of about 500 times a minute the frame B and chuck C above described
revolves with it. One side of the metal chuck C is hollowed out the exact size
which it is intended to make the cups, and the shut of tin A being fixed in the
said frame B so that the place where it is intended to spin a cup is exactly over the
hollowed out or concave side of the metal chuck C The whole is revolved round
at a considerable speed by steam or manual power The centre of the concave
chuck C being the pivot on which the whole frame revolves.
A tool with a round or ball end is then pressed against the sheet of tin A over
the concave or hollowed side of the said metal chuck C and by continuing that
pressure for a few seconds the metal plate gradually assumes the form of the
concave chuck C without cracking or injuring the tin A.
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.) The making or sinking holes in tin-plates for the purposes aforesaid by
spinning instead of by hammering them out on an anvil or otherwise.
(2.) The method of revolving metal chucks C with frames B attached thereto
which shall carry the plates so that any position of such tin-plates can be brought
over the centre or pivot of such chuck C. and allow of them being pressed or sunk
to take the form of the concave side of such chuck or casting.
(3.) Hollowing out such chucks or castings and attaching them to metal frames
as and for the purposes above-described.
Dated this 20th day of June 1886.