Improvements in and relating to Forming Screw-threads on Circular Objects and Cutting Off same.
Year: 1889

page_text: Date of Application, 31st Oct., 1889
Complete Specification Left, 28th July, 1890-Accepted, 20th Sept., 1890
PROVISIONAL SPECIFICATION.
Improvements in and relating to Forming Screw-threads on Circular
Objects and Cutting Off same.
We, JOHN TAYLOR of the Midland Foundry, Queen's Road Nottingham, Engineer
and HENRY WALKER HILL of 47 Hampden Street Nottingham, Engineer, do hereby
declare the nature of this invention to be as follows:-
The object of this invention is to truly cut screw threads on circular objects, and
to cut off these objects to any required length, by improved and simple means.
To effect this purpose, we have one or more cutting or chasing tools carried by
suitable means from a revolving table, on that side of the table nearest the vice or
gripping apparatus; which is so formed, as to hold the object to be screwed or cut,
centrally with this table.
This table revolves in a carrier or saddle, sliding freely on a suitable guide or
guides, attached to the vice or gripping apparatus before named; and the table is
turned by gearing and a handle or other suitable means-carried from the saddle.
The stalk or shank of the revolving table is made hollow; and, has formed on it
internally a screw thread-or in some cases is fitted with a bush having this screw
thread formed on same-in which screws a hollow screwed matrix or leading screw,
firmly fixed to that end of the guide furthest away from the gripping vice. This
matrix is made hollow, to admit of the object to be screwed or cut passing into it.
The screw thread on this hollow matrix, and the hollow shank of the table (or bush)
fitting on it, are both of the same pitch of thread as that required to be cut on the
object to be screwed; and by this means it follows, that as the table is turned round
by its driving gear, it is advanced along the screwed stationary matrix ; and the tool
or tools carried by the table, being brought up to cut the object to be screwed, are
advanced with the table, and truly cut on the object a thread or threads of the same
pitch as that on the matrix or leading screw.
For cutting off tubes or other circular objects, we either disengage the matrix
from the table; or, allow the matrix to slide freely along the guides, and firmly fasten
to the guides the saddle carrying the revolving table and cutting off tool; so that,
the tool or tools in being fed forward to cut off the tube or other object, do not
advance along the length of same, as in the screwing operation.
Dated this 29th day of October 1889.
HENRY WALKER HILL.
COMPLETE SPECIFICATION.
Improvements in and relating to Forming Screw-threads on Ciroular
Objects and Cutting Off same.
We, JOHN TAYLOR of the Midland Foundry, Queens Road Nottingham, Engineer
and HENRY WALKER HILL of 47 Hampden Street Nottingham, Engineer, 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 truly cut screw threads on circular objects, and
to cut off these objects to any required length, by improved and simple means.
To effect this purpose, we have one or more cutting or chasing tools carried by
suitable means from a revolving table, on that side of the table nearest the vice or
gripping apparatus, which is so formed, as to hold the object to be screwed or cut
centrally with this table.

page_text: :
This table revolves in a carrier or saddle sliding freely on a suitable guide or guides
attached to the vice or gripping apparatus before named ; and the table is turned by
gearing and a handle--or other suitable means-carried from the saddle.
The stalk or shank of the revolving table is made hollow; and, has formed on it
internally a screw thread--or in some cases is fitted with a bush having this screw
thread formed on same-in which screws a hollow screwed matrix or leading screw,
firmly fixed to that end of the guide furthest away from the gripping vice. This
matrix is made hollow, to admit of the object to be screwed or cut passing into it.
The screw thread on this hollow matrix, and the hollow shank of the table (or bush)
fitting on it, are both of the same pitch of thread as that required to be cut on the
object to be screwed; and by this means it follows, that as the table is turned round
by its driving gear, it is advanced along the screwed stationary matrix ; and the tool
or tools carried by the table, being brought up to cut the object to be screwed, are
advanced with the table, and truly cut on the object a thread or threads, of the same
pitch as that on the matrix or leading screw.
For cutting off tubes or other circular objects, we either disengage the matrix from
the table; or, we allow the matrix to slide freely along the guides, and firmly fasten
to the guides the saddle carrying the revolving table and cutting off tool; so that,
the tool or tools in being fed forward to cut off the tube or other object, do not
advance along the length of same, as in the screwing operation.
And in order that our invention may be fully understood, and readily carried out
and into effect; we will proceed to describe the accompanying sheet of drawings ;
reference being had to the letters and figures marked thereon.
Figure 1 is a side elevation-partly in section-of our improved screw-cutting
machine.
Figure 2 is an end elevation of the same at end X and partly in transverse
section.
Figure 3 is a plan of the machine also partly in section.
Figure 4 is an end elevation of the machine at the right hand end P (Fig. 1).
Figure 5 is an elevation of the revolving table F1, tool holder and tools.
Similar letters and figures refer to similar parts throughout the several views.
In these views J, J, are the cutting or chasing tools carried in the tool holder.H, K
from the revolving table F' on that side nearest to the vice M, M, which is so formed
as to hold the object or tube P-to be screwed or cut-centrally with this table F¹.
This table revolves in a carrier or saddle E which slides freely on the guides C, C
attached to the arms B, B of the vice case A; the table F¹ is formed-on the opposite
side of cutter box H, Kas a bevel wheel which gears into the bevel pinion F2,
attached to shaft U, turning in bearing S carried from the saddle E. Shaft U is
turned by handle Q. The stalk or shank F of the revolving table F¹ is made-hollow
as shewn, and has formed on it internally a screw thread-or screwed bush-in
which screws the hollow screwed matrix or leading screw T, firmly fixed by bolts X, X
to the cross-bar D which is carried by the guides C, C. This matrix is made hollow
to admit of the pipe P-or other object to be screwed or cut-passing into it.
The screw thread on the matrix T, and hollow shank F fitting on it, are both of
the same pitch of thread as that required to be cut on pipe P; and by this means it
follows, that as the table F¹ and shank F are turned round by handle Q, shaft U, and
pinion F; it is advanced along the screwed stationary matrix T, and the tools J, J
carried by the table F¹, being brought up to the pipe P by set screw L, are advanced
with the table F¹ along pipe P, and cut thereon a thread or threads of the same
pitch as that on matrix T.
For cutting off tubes or other circular objects, we either disengage the leading
screw 'T, from table F¹; or, allow the screw T and cross bar D to slide freely along
the guides CC by unscrewing screw R¹; and firmly fasten the saddle 'E by screw R
to the guides C, C. By this means the tools J, J being fed forward by screw 'L to cut
off the tube P, do not advance along the length of same as in "the screwing
operation.
We prefer to have a spring or other elastic substance between the ends of tools 'J*J,

page_text: and feeding screw I. The tools J J are made to cut the thread on pipe P when
turning the table F' in either direction.
For cutting off lengths of pipes &c. ordinary cutting tools are inserted in
holder H, K.
The gripping jaws M, M are opened or closed centrally from the axis of the
machine, by the right and left hand screw N and handle O.
In some cases, we prefer to have two or more cutter boxes H, K, on the opposite
side of table F¹; each fitted with suitable cutters, so as to act on the pipe P in two
or more points in its circumference at one time. In some cases also we make the
cutters J with two cutting edges W, one behind the other in each cutter.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed and constructed, we declare
that what we claim is :-
1-The combination, in a machine for forming screw threads, of a rotary cutter or
cutters J, J, having one or more cutting edges, with a gradually advancing rotary
table and screwed bush F¹ F and saddle E sliding on guides CC, all substantially
as set forth.
2-In a machine for forming screw threads the combination of the rotary table
and screwed bush F¹ F, and cutters J J with the stationary screwed hollow
matrix T, turning one on the other substantially as described.
3-The combination in a machine for forming screw threads of the rotary
cutters JJ, table and screwed bush F F and stationary hollow matrix T with a
centrally gripping vice M. N, substantially as shown and for the purposes specified.
4-The combination in a machine for forming screw threads, of the means of
fixing the saddle E-carrying the rotary table and bush F¹ F-to guides CC, by
means of screw R and of disengaging matrix T from the bush F for the purpose
of cutting off circular objects to any required length, all substantially as hereinbefore
described.
5 Machines for forming screw threads on circular objects and for cutting these
objects off to any required length substantially as described, and shown in the
drawings hereunto annexed.
Dated this 96th day of July 1800.
HENRY WALKER HILL,
Agent for the Applicants.