Improvements in Tools and Tool-holders for use in Lathes and other Machine Tools.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Tools and Tool-holders for use in Lathes and
other Machine Tools.
I, WILLIAM MURPHY, of Stainton Terrace, Deansgate Lane, Timperley, in
the County of Cheshire, Engineer, do hereby declare the nature of this invention
to be as follows:-
-
This invention has for its object, improvements in swivel toolholders for use
in lathes and other machine tools, and this invention is designed to provide
for the use of an advantageous section of bar steel for the tools or cutters, as
regards the cutting angles of the said tools or cutters. The said section of bar
steel having its top or cutting face bevilled, so as to give a good cutting angle
at its high edge. This invention also provides for using the one section of bar
steel, for either right hand, or left hand cutting tools, according to which end of
the steel is ground, no grinding on the top face of the tools being required, and
the one toolholder being suitable for either right or left hand cutting tools. This
invention also provides for the easy and rapid adjustment in the height of cutting
edge. of the tools or cutters.
The tools or cutters are made of section that is wider at the top, than at the
bottom, and the thickness of the top of this steel is greater than its thickness at
the bottom, in such a proportion, that the two sides slope towards each other at
an inclination of about 1 in 6. And the top face of the steel is bevilled, so that if
the section of steel were placed with its bottom face horizontal, then its top or
cutting face would be inclined to the horizontal at an angle of about thirty
degrees, or other suitable angle with the horizontal, so as to form a good average
angle for cutting, at its high edge.
...I make the toolholder with a shank of square or other suitable section, and at
one end of the shank I make a cylindrical boss. Through this cylindrical boss
I make a cylindrical hole for the reception of a cylindrical piece which said
cylindrical piece being screwed at one end, I will term the swivel bolt. I make
the said cylindrical hole in such manner, that its axis, and consequently the axis
of the said swivel bolt when in the hole, is inclined at an acute angle with the top
of the shank of toolholder. And the said acute angle is of such magnitude or
degree as will, when the tool or cutter is fastened in the said swivel bolt, cause
the said tool or cutter to be presented to its work, with a good average cutting
angle in the direction of the front of the toolholder.
The said inclination of axis of the swivel bolt, also provides for the adjustment
of the height of cutting edge of the tools or cutters.
Through the swivel bolt, a slot is made, of suitable shape for the section of
steel used for the cutters, and the said slot is made at right angles with the axis
of the said swivel bolt, so that it is immaterial which end of the slot is to the
front of toolholder. Over the tool, and between it and the under surface of the
cylindrical boss, is a collar, and this collar has an angular notch or groove, cut
diametrically across its lower face the said notch or groove being of a right-

page_text: angled triangular shape, so as to suit the section of the steel bars from which
the tools or cutters are made. In using the toolholder, the forward end of the
tool or cutter is ground to the desired shape, and when set to the required position
in the holder, all the parts are tightly bound together by screwing up the nut
of the swivel bolt, which said nut bears on the top face of the cylindrical boss.
And when it is desired to change the tools from right hand to left, or from left
hand to right hand, it is only necessary to turn the swivel bolt and collar, or
the collar alone, through half a revolution on its axis.
My invention is illustrated by the accompanying drawings, in which Fig. 1
is a side view. Figs. 2 and 3, front views showing the different positions of
collar for right and left hand tools, and Fig. 4, is a plan. The reference letters
used denote the different parts as follows:-A is the shank. B the swivel bolt.
C the collar, and T the tool or cutter. In the plan T T and T are intended
to show how the tools can be swiveled round to any desired position.
Dated this 26th day of March 1898.
Improvements in Tools and Tool-holders for use in Lathes and
other Machine Tools.
I, WILLIAM MURPHY, of Stainton Terrace, Deansgate Lane, Timperley, in
the County of Cheshire, 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:-
This invention has for its object, improvements in swivel toolholders for use
in lathes and other machine tools, and this invention is designed to provide
for the use of an advantageous section of bar steel for the tools or cutters, the
said section being made advantageous or improved as regards the cutting angle
of the said tools or cutters, the shape of the said section of bar steel having its
top or cutting face bevelled, so as to give a good cutting angle at its high or
forward edge. This invention also provides for using the one section of bar
steel for either right-hand or left-hand cutting tools, without requiring the
cutting face of the tools to be ground specially for that purpose, and the one tool-
holder being suitable for holding either right-hand or left-hand cutting tools.
This invention also provides for the easy and rapid adjustment of the height of
cutting edge of the said tools or cutters.
My invention is illustrated by the accompanying drawings, in which Fig. 1, is
a side view of a toolholder for holding the tool so that the cutting point is below
or behind the bottom face of the shank of toolholder. Fig. 2, is a side view of a
toolholder for holding the tool so that the cutting point is higher than the
bottom face of the shank of toolholder. Fig. 3, is a plan or top view showing the
manner in which the tools may be swivelled round. Fig. 4, is an end view
showing the holder adapted for and holding a right-hand cutting tool. Fig. 5
shows the same holder with the loose collar turned through half a revolution
from the position shown in Fig. 4, and thus adapted for holding a left-hand
cutting tool. Fig. 6, shows the shape of transverse section of tools made accord-
ing to my invention. Fig. 7, Fig. 8, Fig. 9, and Fig. 10, show different forms
of section of the toolholder shank, and the sectional shape of packing pieces used
when the tools have to be swivelled round to any considerable extent.
In carrying my invention into effect, the tools or cutters (t) are made of
uniform transverse section throughout their length, the said section being wider,

page_text: at the top or cutting face (a¹) than at the bottom (a2), for the purpose of giving
clearance underneath the cutting edge, and the top or cutting face (a¹) being
bevelled, so that if the section of steel were placed in such manner that its two
longer sides (a³) would be equally inclined to the vertical, and the narrow
face (a2) at bottom, then the top or cutting face (a¹) would be inclined upwards
to the horizontal at an angle of about thirty degrees or other suitable acute angle,
for the purpose of giving a good cutting angle at its high edge. An illustration
of the above form of section is shown by Fig. 6, on the accompanying drawing.
Preferably, toolsteel bars of the aforesaid form of section are produced by
rolling, but they may be made by cutting or otherwise removing the requisite
portion of metal from toolsteel bars of rectangular section, or which are already
wider on one edge than on the other, but are not bevelled on the wider edge.
I make the toolholder shank (A) of rectangular, circular, or other suitable
form of transverse section, and at one end of the shank (A), I make a cylindrical
boss, through this boss I make a cylindrical hole for the reception of a cylindrical
piece (B), which piece being screwed at one end and fitted with a screwnut (N)
I will hereinafter refer to as the swivelbolt (B). I make the said cylindrical
hole in such manner that its axis, and consequently the axis of the swivelbolt (B)
when in the hole, is inclined at an acute angle (20) (Fig. 2) to the top of the
toolholder shank (A), and this acute angle (0) is of such magnitude or degree as
will, when the tool or cutter (t) is fastened in the swivel-bolt (B), enable the tool
or cutter (t) to be presented to its work with a good cutting angle, so far as con-
cerns front top-rake, in the direction of the front of toolholder, as the tool or
cutter (t) will then have its top or cutting face inclined forward and upwards to
the horizontal. The aforesaid inclination of axis of the swivelbolt (B), also pro-
vides for the adjustment in the height of cutting edge of the tools or cutters (t),
according as the tools (t) are projected more or less through the slot in swivel-
bolt (B). Through and at right angles to the axis of the swivelbolt (B), a slot
is made of suitable shape for the reception of the tools or cutters (t). The swivel-
bolt (B) is fitted with a loose collar (C), which is placed over the tool (t) and
between the tool (t) and the under surface of the cylindrical boss, and the
collar (C) has an angular notch or groove (g) cut diametrically across its lower
face, so that one side of the angular notch or groove will correspond to the
bevelled top or cutting face on tools which are of similar transverse section to
that herein before described. In using the tools and toolholder, the tools having
been severed in suitable lengths, from toolsteel bars of the aforesaid section, the
end of the tool as required for left-hand or right-hand cutting, is ground to the
desired shape of point, and when set to the required position in the holder, all
the parts are firmly bound together by screwing up the nut (N) on swivelbolt (B),
the said nut (N) tightening against the top face of the cylindrical boss. By
turning the notched collar (C) through half a revolution on its axis, the toolholder
is made suitable for holding the opposite hand of cutting tool, to that held before
the half revolution of collar. When it is required to use the tools swivelled
round sideways to any considerable extent, there is placed under the toolholder
shank, a packing piece which has a face inclined transversely to its length, so as
to compensate for the reduction in upward inclination of the tools, which is
caused by turning about the axis of the swivelbolt. Fig. 7, shows a very con-
venient and efficient form of packing piece, and the form of shank (A¹) provides
a top face which is parallel to the under face of the packing piece, so that no
packing piece is needed for the top face of the shank. Fig. 8 and Fig. 9 show
a rectangular shank (A²) and a pair of packing pieces, the inclination to either
hand being reversed by turning the packing pieces end for end. Fig. 10 shows
a circular shank (A³) with a pair of hollow packing pieces, this arrangement not
being so firm as in Figures 7, 8, and 9, but extremely convenient for light work
and screwcutting.

page_text: Having now particularly described and ascertained the nature of my said in-
vention, and in what manner the same is to be performed, I declare that what I
claim is:-
Firstly. A tool or cutter which is of uniform transverse section throughout its
length, the shape of the said section being wider at the top or cutting face than
at the bottom, and having the top or cutting face bevelled so as to make a more
acute angle at one edge of the top or cutting face than at the other edge of top
or cutting face, substantially the same as described in the foregoing specification,
and for the purpose stated.
Secondly. A toolholder constructed substantially the same as described in the
foregoing specification, and illustrated by the accompanying drawings, and for the
purpose stated.
Thirdly. A swivel toolholder shank which has a hole for the reception of the
swivelbolt, formed at its end in such manner that the axis of the hole is inclined
at an acute angle with the top face of toolholder shank, substantially the same
as described in the foregoing specification, and for the purpose stated.
Fourthly. The combination with a toolholder of the character herein described,
of a tool or cutter which has a similar shape of transverse section throughout its
length, to that herein described, and for the purpose stated.
Dated this 30th day of November 1898.
WILLIAM MURPHY.