IMPROVEMENTS IN TURNING TOOLS AND IN MACHINERY OR APPARATUS THEREFOR
Year: 1871

page_text: LETTERS PATENT to William Spence, of 8, Quality Court, Chancery
Lane, in the County of Middlesex, Patent Agent, for the Invention
of "IMPROVEMENTS IN TURNING TOOLS AND IN MACHINERY OR APPARATUS
THEREFOR."-A communication from abroad by John Fensom, of
Toronto, in the Dominion of Canada, Engineer.
Sealed the 7th May 1872, and dated the 30th November 1871.
PROVISIONAL SPECIFICATION left by the said William Spence at the
Office of the Commissioners of Patents, with his Petition, on the
30th November 1871.
I, WILLIAM SPENCE, of 8, Quality Court, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of the
said Invention för "IMPROVEMENTS IN TURNING TOOLS AND IN MACHINERY OR
APPARATUS THEREFOR," (being a communication to me from abroad by
John Fensom, of Toronto, in the Dominion of Canada, Engineer,) to
be as follows:-

page_text: shafting and similar articles, and to an improved mode of constructing
the bed of lathes employed for turning such articles.
The improvement in the cutter or die consists in making the front
cutting edge of the same like a chaser or screw cutter, the thread of
which gradually diminishes in depth until it runs completely out, leaving
the back portion a broad cutting edge, which is in the same plane as
the innermost parts of the first thread. In this manner the thread
which is commenced by the first cutting edge is utilized or caused to
operate as a feeder for the cutter, but is gradually cut away as the
threads in the cutter become less deep, and is completely removed
by the back cutting edge. The effect produced by a cutter of this kind
is that of distributing the cutting points, and thereby reducing the
friction upon them, while at the same time the cutter is self-feeding.
The improvement in the bed of the lathe consists in constructing the
same in the shape of a trough, and without the ordinary heads, the
spindles fitting through each end of the lathe bed in such a manner
that the centres or holding parts are immersed in water when this trough-
shaped lathe bed is filled therewith. The object of this arrangement
is to keep the iron well lubricated and cool while under the operation
of turning.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Spence in the Great Seal Patent Office on
the 30th May 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
SPENCE, of 8, Quality Court, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of November, in the
year of our Lord One thousand eight hundred and seventy-one, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Spence, Her special
licence that I, the said William Spence, my executors, administrators,
and assigns, or such others as I, the said William Spence, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term

page_text: therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
TURNING TOOLS AND IN MACHINERY OR APPARATUS THEREFOR," being a com-
munication to me from abroad by John Fensom, of Toronto, in the
Dominion of Canada, Engineer, upon the condition (amongst others)
that I, the said William Spence, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said William Spence, do hereby declare
the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the Drawings hereunto
annexed, and to the letters and figures marked thereon (that is to say) :-
This Invention of "Improvements in Turning Tools, and in Machinery
or Apparatus therefor," relates to an improved cutter or die for turning
shafting and similar articles, and to an improved mode of constructing
the bed of lathes employed for turning such articles.
The improvement in the cutter or die consists in making the front
cutting edge of the same like a chaser or screw cutter, the thread of
which gradually diminishes in depth until it runs completely out,
leaving the back portion a broad cutting edge, which is in the same
plane as the innermost part of the first thread. In this manner the
thread which is commenced by the first cutting edge is utilized or caused
to operate as a feeder for the cutter, but is gradually cut away as the
threads in the cutter become less deep, and is completely removed
by the back cutting edge. The effect produced by a cutter of this kind
is that of distributing the cutting points, and thereby reducing the
friction upon them, while at the same time the cutter is self-feeding.
The improvement in the bed of the lathe consists in constructing the
same in the shape of a trough, and without the ordinary heads, the
spindles fitting through each end of the lathe bed in such a manner
that the centres or holding parts are immersed in water, when this

page_text: DESCRIPTION OF THE DRAWINGS.
Fig. 1 is a front view of an ordinary blacksmith's stock holding a pair
of cutters or dies, and Fig. 2 is a transverse vertical section of the same
in the line x, y, of Fig. 1.
A, A, are the cutters or dies, which in Fig. 2 are represented as
performing the operation of turning a piece of shafting. It will be seen
on reference to this Figure that the front part a of the cutter A com-
mences with a full thread, but which gradually becomes less deep until
it runs completely out, and leaves the back part 6 a broad cutting edge,
which entirely removes the thread produced by the front part a, and
leaves the shafting plain and smooth, and reduced in diameter, as shewn
at C. It will thus be seen that blacksmiths and others who do not
usually possess machinery for turning can with these dies or cutters A, A,
utilize their ordinary stock for that purpose. The said dies or
cutters A, A, may be applied in various ways, either singly or in any
number to common or bolt cutting lathes, either with or without the
usual feeding gear as may be required. Cutters on this principle can
be used for every description of turning.
Fig. 3 shews an ordinary screw cutting die connected to a cutter,
which will answer in a rough way the purpose of the cutter or die A.
Fig. 4 is a transverse vertical section, shewing the improvement in
the bed of the lathe herein-before referred to. It will be understood
that the revolving spindle passes through the end of the bed D, which
is of course fitted with proper journal boxes and requisite bearings. The
tool rest E must also be shaped so as to admit of the shafting or other
iron under operation being held in the position shewn at F, that is to
say, in a position immersed in the water contained in the trough-shaped
bed D. Both the bed D and the tool rest E may be varied in form,
provided they are respectively adapted for the purpose described of

page_text: keeping the iron well lubricated and cool, while under the operation of
turning..
Having thus described the nature of the said Invention communi-
cated to me from abroad as aforesaid, and in what manner the same is
to be performed, I hereby declare that what I claim as the said Inven-
tion is,―
First. The use of a cutter or die with the front cutting edge formed
with a deep thread like a chaser, and with the cutting thread diminishing
in depth till it runs completely out, leaving the back part a broad
cutting edge as represented at Fig. 2, as and for the purpose described.
Secondly. In connecting a screw cutting die with a cutter, so that
the two combined will roughly answer the purpose of the two parts a
and b of the said cutter or die.
And, lastly. The construction of lathe beds trough shaped, and the
centres or holding parts suitably formed to admit of shafting or other
articles being turned while immersed in water for the purpose described.
In witness whereof, I, the said William Spence, have hereunto set
my hand and seal, the Thirtieth day of May, in the year of
our Lord One thousand eight hundred and seventy-two.
Witness,
W. A. JACKSON,
8, Quality Court,
Chancery Lane.
WILLIAM SPENCE. (L.S.)