IMPROVEMENTS IN STOCKS AND DIES FOR SCREWTHREADING PIPES AND OTHER ARTICLES, ALSO APPLICABLE TO SCREW CUTTING MACHINES
Year: 1878

page_text: LETTERS PATENT to Harry Oscar Choles, of Upper Clapton, in the County of
Middlesex, for the Invention of "IMPROVEMENTS IN STOCKS AND DIES FOR
SCREWTHREADING PIPES AND OTHER ARTICLES, ALSO APPLICABLE TO SCREW
CUTTING MACHINES."
Sealed the 14th March 1879, and dated the 24th December 1878.
"
PROVISIONAL SPECIFICATION left by the said Harry Oscar Choles at the
Office of the Commissioners of Patents on the 24th December 1878.
HARRY OSCAR CHOLES, of Upper Clapton, in the County of Middlesex.
IMPROVEMENTS IN STOCKS AND DIES FOR SCREWTHREADING PIPES AND OTHER
ARTICLES, ALSO APPLICABLE TO SCREW CUTTING MACHINES."
My Invention relates to stocks and dies for screw threading gas and other pipes,
bolts, or rods; it is also applicable to screw cutting machines.
My Invention has for its object, 1st, to remove the "burr" thrown up on the end
of the pipe in cutting it to length, and also the hard outer surface of the pipe in
advance of the screw-cutting die, but at the same operation, in order to prepare the
pipe for the action of the die; 2ndly, to provide a leading screw to feed the die
along the pipe as it cuts the screw thread, thereby facilitating the operation by
relieving the die of this part of its work, and ensuring the formation of a perfectly
true screw-thread.
According to my Invention I provide the guide, through which the pipe passes
before entering the die, with a cutter or ring of cutters on the interior at the upper
Duins B17

page_text: The
end or that next the die, whereby on rotating the stock in the ordinary way of
cutting the screwthread the "burr" and hard outer skin are removed from the pipe
just before it enters the die and at one and the same operation as the cutting of the
screw thread, instead of a previous operation by means of a file as usual.
guide is connected to the stock by being flanged at the upper end, and keyed in a
recess in the stock in the usual way, and the lower end of this guide is screw
threaded to screw in or on a screw formed on or connected to a collar firmly clamped
on the pipe. This screw is of exactly the same pitch as the screw to be cut on the
pipe by the die, and as the guide screws upon it, it thus forms a feed or leading
screw to feed the die along the pipe when in work.

page_text: Figure 1 is an elevation of a die stock provided with the improvements of my
Invention; Figure 2 is a top view thereof; and Figure 3 is a central section of the
same on line 1-1, Figure 2, showing all the parts in position; Figure 4 is a top
view of the stock, the die and its locking devices being removed therefrom, showing
the ring of cutters on the guide; Figure 5 is a similar view of the stock alone,
showing the socket in which the said guide is received; lastly, Figures 6, 7, and 8
are respectively a top end view, elevation, and bottom end view of the guide
alone.
The same letters of reference indicate the same parts in all the Figures.
A is the stock and B the die locked in its recess therein by milled nuts C
screwing on pins c, fixed in the stock in recesses formed partly in the stock
and partly in the die in which the nuts are received, all as usual; D is the tubular
guide provided with a flange d at one end, received in a correspondingly rebated
socket in the stock A, and keyed therein by half round notches d' in the flange d,
embracing corresponding bosses a formed on the stock A, and projecting into the

page_text: rebate of the socket. The die B and its nuts C hold the guide D securely in place.
So far the guide is much the same as usual.
E is an interior ring of cutters formed on the guide D at the end next the
die B.
Their form is clearly shewn in Figure 4, and they give passage to the pipe F to
be screw threaded after removing the "burr" and hard outer skin therefrom. The
remainder of the guide D is enlarged internally so as not to touch the pipe, and is
screw threaded internally to screw upon an externally threaded tubular portion g
of a collar G, which fits loosely on the pipe F, and is firmly clamped thereto by
means of a set screw H. The pipe F being fixed in a vice or otherwise held, as
usual, it will be readily seen how on rotating the stock the guide D is caused to
traverse the screw g, thereby feeding the cutters E and the die B along the tube,
the action of the cutters preceding that of the die, as above explained.
It will be obvious without further illustration that the guiding screw may be on
the exterior of D, and on the interior of g if the latter be made large enough to
receive the former within it.
Having described the nature of my Invention and the manner of performing the
same, I would observe that although the Invention may be used in screw cutting
machines I do not claim it as applied thereto, but what I do claim as my Invention
to be protected by the hereinbefore in part recited Letters Patent is,-.
1st. The combination with a hand screwing stock and die of an internal ring of
cutters placed beneath the die so as to precede it in its action on the pipe, substan-
tially as and for the purpose specified.
2nd. The combination with a screwing stock and die of a guide adapted to screw
on or in a leading or feed screw fixed to the pipe to be screw threaded, substan-
tially as and for the purpose specified.
3rd. The combination with a screwing stock and die of a tubular guide having
an internal ring of cutters at its end next the die, and of a leading or feed screw
formed partly on the other end of the said guide, and partly on a collar fixed to the
pipe to be screw threaded, substantially as and for the purpose specified.
In witness whereof, I, the said Harry Oscar Choles, have hereunto set my
hand and seal, this Eighteenth day of June, in the year of our Lord One
thousand eight hundred and seventy-nine.
CHOL TO
H. C. CHOLES. (L.S.)