IMPROVE- MENTS IN MACHINERY FOR THE MANUFACTURE OF SCREW CAPS OR STOPPERS. AND HOLLOW SCREWS
Year: 1876

page_text: ⋅
LETTERS PATENT to Thomas George Fonnereau Dolby, of 22, Camberwell
Green, in the County of Surrey, Manufacturer, for the Invention of "IMPROVE-
MENTS IN MACHINERY FOR THE MANUFACTURE OF SCREW CAPS OR STOPPERS.
AND HOLLOW SCREWS."
Sealed the 7th April 1876, and dated the 14th January 1870.
PROVISIONAL SPECIFICATION left by the said Thomas George Fonnereau
Dolby at the Office of the Commissioners of Patents on the 14th January 1876.
THOMAS GEORGE FONNEREAU DOLBY, of 22, Camberwell Green, in the County of
Surrey, Manufacturer, "IMPROVEMENTS IN MACHINERY FOR THE MANUFACTURE OF
SCREW CAPS OR STOPPERS AND HOLLOW SCREWS."
The chief object of my Invention is to construct machinery by means of which
screw caps or stoppers can be accurately made, and it is intended to apply more
particularly to caps or stoppers of sheet metal, such, for example, as gold, silver,
copper, brass, iron, tin plate, German silver, and others.
My machinery consists of three main parts, viz., a female screw die, a male screw
die, and a screw box, in which the screw shaft which carries one of the dies works.
These three parts must all correspond, that is to say, the pitch of the female
and male screws and of the screw box and shaft must be the same, their centres
must all be in the same line, and the relative positions of the male and female dies -
must be such that the male die will properly enter the female die. The difference
in the diameter of the male and female dies corresponds with the thickness of the
metal or material from which the cap or stopper is to be made.
The operation is as follows:--A plain hollow cap is placed at the entrance to the
female die or on the male die, the male die is then brought down, and entering the
female die carries the cap with it, and owing to the rotary motion which the male
die has in its descent, it follows that the cap rotates on it, and is forced into the
threads of the female and male dies. The cap has thus both an external and an
internal screw formed thereon. Upon reversing the motion the male die rises,
generally taking the cap with it, or sometimes the cap remains in the female die; in
either case it can be removed by hand or by a suitable hand tool.
By means of machinery constructed as before described caps or stoppers can be
economically made from sheet metal, which can be employed in lieu of caps or
stoppers, such as now cast, of unnecessary weight.
17.7++

page_text: Although I have herein-before referred to the manufacture of caps or stoppers,
the machinery is also capable of manufacturing hollow screws, a plain tube being
in this case placed upon one of the dies.
Dies of various diameters can be substituted one for another in the same machine
as required, provided always that the pitch of the screw is the same.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas George Fonnereau Dolby in the Great Seal Patent Office on
the 13th July 1876.
THOMAS GEORGE FONNEREAU DOLBY, of 22, Camberwell Green, in the County of
Surrey, Manufacturer. "IMPROVEMENTS IN MACHINERY FOR THE MANUFACTURE OF
SCREW CAPS OR STOPPERS AND HOLLOW SCREWS."
The chief object of my Invention is to construct machinery by means of which
screw caps or stoppers can be accurately made, and it is intended to apply more
particularly to caps or stoppers of sheet metal, such, for example, as gold, silver,
copper, brass, iron, tin plato, German silver, and others.
My machinery consists of three main parts, viz., a female screw die, a male screw
die, and a screw box, in which the screw shaft which carries one of the dies works.
These three parts must all correspond, that is to say, the pitch of the female and
male screws and of the screw box and shaft must be the same, their centres must all
be in the same line, and the relative positions of the male and female dies must be
such that the male die will properly enter the female die. The difference in the
diameter of the male and female dies corresponds with the thickness of the metal or
material from which the cap or stopper is to be made.
Figures 1 and 2 of the annexed Drawings are sectional clevations taken at right
angles to each other of a machine constructed according to my Invention.
a is the frame and b the bed of the machine; c is a vertical screw shaft working
in the screw box d and guide o; fis the male screw die secured to the end of the
shaft c; and g is the female screw die secured to the bed b.
The pitch of the screw of the screw box d, of the male die f, and the female die g
must, as has been already explained, be the same, their centres or axes must be in
the same line, and the difference in the diameter of the male and female dies must
correspond with the thickness of the metal from which the cap or stopper is to be
made.
The operation is as follows:-A plain hollow cap (such, for example, as that
shewn full size in section in Figure 3) is placed at the entrance to the female die g
or on the male die f, the male die is then brought down by rotating the handle h,
and entering the female die carries the cap with it, and owing to the rotary motion
which the male die has in its descent, it follows that the cap rotates on it, and is
forced into the threads of the female and male dies. The cap has thus both an
external and an internal screw formed thereon, as seen in the sectional view,
Figure 4. Upon reversing the motion the male die rises, generally taking the cap
with it, or sometimes the cap remains in the female die; in either case it can be
removed by hand or by a suitable hand tool.
By means of machinery constructed as before described caps or stoppers can be
economically made from sheet metal, which can be employed in lieu of caps or
stoppers, such as now cast, of unnecessary weight.
Although I have herein-before referred to the manufacture of caps or stoppers,
the machinery is also capable of manufacturing hollow screws, a plain tube being
in this case placed upon one of the dies.
Dies of various diameters can be substituted one for another in the same machine
as required, provided always that the pitch of the screw is the same.
And having now described the nature of my said Invention, and in what manner
the same is to be performed, I declare that I claim, constructing machinery for

page_text: manufacturing screw caps or stoppers and hollow screws, substantially as herein-
before described and represented in the annexed Drawings, that is to say, with
male and female screw dies and a screw shaft, arranged and working together as
and for the purpose explained.
In witness whereof, I, the said Thomas George Fonnereau Dolby, have hereunto
set my hand and scal, this Eleventh day of July, One thousand eight hundred
and seventy air
T. G. F. DOLBY. (LS.)