An Improved Method of Milling or Corrugating Metal Screw Caps 'or Stoppers for Bottles, Jars, and the like.
Year: 1890

page_text: Date of Application, 22nd May, 1890-Accepted, 12th July, 1890
AAMI LEIN DIEUIFICATION.
An Improved Method of Milling or Corrugating Metal Screw Caps
'or Stoppers for Bottles, Jars, and the like.
THOMAS SUTCLIFFE Stopper Manufacturer 4 & 6 Blundell Street Caledonian Road
London Middlesex 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 :-
My improvement consists in the Milling or Corrugating of tinned iron or other
metal Screw Caps or Stoppers for bottles, jars and the like. The said milling or
corrugating being performed on the cap, before the screw thread is impressed on
the said cap.
According to the present method of milling or corrugating these screw caps, the
milling is performed after the screw thread is made on the said cap, this is not only
a very difficult task but the milling of the harder metal caps has never been a success,
because after the cap has been screwed or threaded, the said screwed cap cannot be
milled deep enough to allow the hand a firm grip, and unless there is a firm grip
for the hand a woman or girl could not unscrew the cap off the neck of the bottle,
jar or the like, as it is necessary for the cap to form an airtight joint with the bottle
neck to keep the contents from spoiling, and, to get an airtight joint the cap must be
screwed well on to the neck of the bottle.
By my improvement however I do not merely mill the outer edge of the thread
of the screw cap but I mill the sides of the cap throughout, therefore the whole
of the thread is milled affording a very firm grip for the hand which has never
yet been attained in tinned iron or other hard metal caps, I do not however allude
to those screw caps where there is an additional screw thread placed inside a milled
or corrugated cap, as I know these are in use, but my improvement relates to a
screw cap made from a single piece of tinned iron or other sheet metal as herein-
after described.
The operation is as follows:-I first stamp out the cap in the ordinary way
either with a plain cap die or with a corrugated cap die the latter of course corrugating
the whole of the sides of the cap. In the former case I should mill or corrugate
the plain cap with a suitable milling tool, as usual with plain milled caps, but
in the latter case the cap is already milled or corrugated. The cap being milled is
now screwed with a suitable screwing or threading tool, and then I have a screw
cap with the sides milled throughout which is a great advantage because not
only is the outside of the thread milled but the whole of the thread improving
the appearance of the cap and giving an extra grip for the hand.
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 :-
The improved method of Milling or Corrugating metal screw caps or stoppers
for bottles, jars and the like before the said screw caps have been screwed or
threaded.
Dated Mo 99nd 1890
THOMAS SUTCLIFFE.