Improvements in Milling Cutters and Means for Fixing the Work on the Table of a Machine Tool.
Year: 1898

page_text: Date of Application, 6th Apr., 1898
Complete Specification Left, 30th Dec., 1898-Accepted, 18th Feb., 1899
PROVISIONAL SPECIFICATION.
Improvements in Milling Cutters and Means for Fixing the Work on
the Table of a Machine Tool.
I, WILLIAM HILLMAN, of 7, The Quadrant, Coventry, in the County of Warwick,
Engineer, do hereby declare the nature of this invention to be as follows:-
The object of my invention is to provide a simple means or apparatus for holding
a piece of metal or work on the table of a machine tool while it is cut or shaped
to the desired dimensions and to produce a milling cutter having detachable and
adjustable cutting tools which may be ground on an ordinary tool grinder or a
grindstone the said tools being so arranged in the body of the cutter that their
cutting edges present acute angles to the work which they enter with greater
facility than do the teeth of ordinary milling cutters.
In carrying my invention into effect as applied to a milling cutter for facing
metal I form the body or holder having a hub with arms, the hub being bored
to fix on an arbor in the usual way..
On one side of each arm I cut a curved V groove in the line of the axis of rota-
tion of the cutter.
The cutting tools are triangular in section and curved to fit the grooves in the
arms in which they are held by bolts, holes being bored for the said bolts through
the arms so that the boring passes through part of the curved V grooves. I cut a
groove or notch in the said bolts by means of which the cutting tools are drawn
tightly down into their grooves.
By varying the radius of the curvature of the cutting tools I am enabled to get
a more or less acute angle for the cutting edges of the cutting tools according to
the toughness of the metal required to be cut that is to say:-
For cast or wrought iron a comparatively small radius for the curve of the cutting
tools may be used giving a more acute angle than the larger radius to which I
should curve the cutting tools for metals such as steel.
When applying my invention to a hollow milling cutter for reducing the diameter
of rods of metal I use the same form of cutting tools and grooves and hold them
in the same manner as described for face milling, but the curved grooves I cut
across the face of the body and the body I form dise shaped with a shank or arbor
attached and bore a hole therethrough of suitable size. This cutter may be rotated
upon the work or the work rotated and the cutter held stationary.
I may form the said milling cutters so as to use straight cutting tools instead of
curved ones in which case I cut the V grooves at an angle with the axis of the
body by which means I get the required angle for the cutting edges of the cutting
tools.
My apparatus for holding work to be shaped or cut
tool consists of a screwed sleeve having a flange for its
the table by means of an ordinary nut and bolt in the
Upon the said screwed sleeve I mount a steel plate
thread to fit the screwed sleeve.
on the table of a machine
base and is held firmly on
slot of the said table."
which I bore and screw

page_text: One end of the plate I curve eccentrically to the axis of the screwed sleeve, and
the edge so curved I cut with sharp grooves or serrations and harden them.
In operation the said plate will generally be screwed down on the screw sleeve
to within about one thread of its lowest limit the eccentric end of the plate being
close to the work to be held.
The plate being turned with a spanner or other lever the hardened serrations
bite into the work and as the plate revolves on the screwed sleeve the work is not
only jammed laterally but also forced tightly upon the table.
On large pieces of work I prefer to use several sets of my apparatus in pairs with
right and left handed screw threads on their sleeyes.
Dated this Cith day of Anril 1808
HARRIS & MILLS,
23, Southampton Buildings, London, W.C.,
Agents.
Improvements in Milling Cutters and Means for Fixing' the Work on
the Table of a Machine Tool.
I, WILLIAM HILLMAN, of 7, The Quadrant, Coventry, in the County of Warwick,
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 my invention is to provide a simple means or apparatus for holding
a piece of metal or work on the table of a machine tool while it is cut or shaped
to the desired dimensions, and to produce a milling cutter having detachable and
adjustable cutting tools which may be ground on an ordinary tool-grinder or a
grindstone, the said tools being so arranged in the body of the cutter that their
cutting edges present acute angles to the work, which they enter with greater
facility than do the teeth of ordinary milling cutters.
My invention is illustrated in the accompanying drawings, in which Fig. 1 is a
face view and Fig. 2 is an edge view of a milling cutter for facing metal, one
curved cutting tool only being shown in position.
Fig. 3 is an edge view of a nut and bolt used for holding the cutting tools in
position.
Fig. 4 is an edge view of a similar milling cutter to that shown at Figures 1
and 2, but having straight cutting tools.
Fig. 5 is a face view of a hollow milling cutter for reducing the diameter of a rod
of metal, and Fig. 6 is a side view thereof but only showing one curved cutting
tool in position.
Figures 7 and 8 are views of a cutter similar to that shown at Figures 5 and 6,
but having straight cutting tools.
Fig. 9 is a plan and Fig. 10 is a side view partly in section showing the appar-
atus for holding the work to be shaped or cut on the table of a machine tool.
In all the figures like parts are indicated by similar letters of reference.
In carrying my invention into effect as applied to a milling cutter for facing
metal, as shown at Figures 1 to 4, I form the body or holder with a hub a and
arms a¹, the hub a being bored to fit on to an arbor and be fixed thereon in the usual
manner. On one side of each arm a¹, I cut a V groove a², which may be curved
as shown in Figures 1 and 2, or straight as shown in Fig. 4.
The cutting tools bare triangular in cross section and formed either curved or

page_text: straight to fit the grooves a² in the arms a', in which they are held by bolts c,
holes a being bored for the said bolts c through the arms a¹ so that the boring
passes through part of the V grooves. I cut a groove or notch c¹ in the said bolts c
to fit the cutting tools b, by means of which the said cutting tools bare drawn
tightly down into their grooves a² by the nuts 2. By varying the radius of the
curvature of the cutting tools b and grooves a² I am enabled to get a more or less
acute angle for the cutting edges of the cutting tools, according to the toughness
of the metal required to be cut, and when employing straight cutting tools as
shown in Fig. 4, a like effect may be obtained by varying the angle of the grooves a²
to the axis of rotation. It will be understood that for cast or wrought iron, a com-
paratively small radius may be used for the curve of the cutting tools b giving
a more acute angle than the larger radius to which I curve the cutting tools for
metal such as steel.
In Figures 5 and 6 I have shown a hollow milling cutter for reducing the
diameter of rods of metal. For this class of apparatus I use the same form of
cutting tools and grooves and hold them in the same manner as above described,
but the grooves a² are cut across the face of the body a* which is formed of disc
shape, and to which is attached a shank or arbor a with a hole a bored there-
through of suitable size.
With milling cutters of this description the radius of the curvature of the grooves
may be varied in a similar manner to that above described to obtain a more or less
acute angle for the cutting edges according to the toughness of the metal it is
intended to cut:
-
In Figures 7 and 8 I have shown another form of hollow milling cutter in which
straight cutting tools are used, in which case I cut the V grooves a² at an angle
as shown, by which means I get the required angle for the cutting edges of the
cutting tools, which angle may be varied according to the class of metal intended
to be cut thereby.
Hollow milling cutters made according to Figures 5, 6, 7, and 8 may be rotated
upon the work, or the work may be rotated and the cutters held stationary.
In Figures 9 and 10 I have shown the apparatus for holding the work to be
shaped or cut on the table of a machine tool. It consists of an externally screwed
sleeve having a flange for its base, which is held firmly on the table g by
means of an ordinary bolte and nut f in the slot g¹ of the said table g. Upon
the said screwed sleeve I mount a steel plate h, which is bored and screw
threaded to fit the screwed sleeve . The outer end of the plate his curved
eccentrically to the axis of the screwed sleeve, and the edge is cut with sharp
grooves or serrations h² which are hardened. In operation the plate h will generally
be screwed down on the screwed sleeve to within about one thread of its lowest
limit, the eccentric end of the plate being close to the work to be held. The
plate is then turned by a spanner or other lever and the hardened serrations 2
bite into the work, and as the plate h revolves on the screwed sleeve d, the work
is not only jammed laterally but also forced tightly down on to the table 9. The
plate is preferably recessed to receive the flange of the screwed sleeve 7, so
that the said plate h will come down nearly into contact with the face of the table
if necessary.
On large pieces of work I prefer to use several sets of my apparatus in pairs with
right and left handed screw threads on their sleeves.
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:-
1. A milling cutter having V shaped grooves to receive cutting tools of triangular
cross section held in position by means of grooved bolts and nuts, substantially as
herein shown and described.
2. A milling cutter formed with a central hub and a number of projecting arms,
cach of which has a groove to receive a cutting tool of triangular cross section held

page_text: in position by means of a grooved bolt and nut, substantially as herein shown and
described.
3. A hollow milling cutter having a disc shaped body with a number of grooves
cut in its face to receive cutting tools of triangular cross section held in position
by means of grooved bolts and nuts, substantially as herein shown and described.
4. An apparatus for holding work on the table of a machine tool, consisting of a
perforated screw threaded plate, having an eccentric edge, capable of being rotated
upon a screwed sleeve, held firmly on the table of the machine tool by suitable
means, substantially as herein shown and described.
5. In an apparatus for holding work on the table of a machine tool, the com-
bination of a perforated screw threaded plate having an eccentric edge formed
with hardened threads thereon, with a screwed sleeve having a flange and capable
of being held on the table of the machine tool, substantially as herein shown
and described.
Dated this 20th day of December 1898
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents,