ACCURATELY SHAPING AND SHARPENING THE CUTTING EDGES OF ROUND NOSED, SINGLE AND DOUBLE ANGLED, FLAT, SIDE CUTTING AND OTHER TOOLS USED FOR ORNAMENTAL TURNING AND OTHER PURPOSES
Year: 1885

page_text: 37 3
i'
THOMAS JOHN ASHTON; gentleman, of No 20 Park Square East N.W. and JoHN
JACOB HOLTZAPFFEL, Engineer of N° 64: Charing Cross S.W. both in the County of:
Middlesex do hereby declare the nature of their invention for ACCURATELY
SHAPING AND SHARPENING THE CUTTING EDGES OF ROUND NOSED, SINGLE AND
DOUBLE ANGLED, FLAT, SIDE CUTTING AND OTHER TOOLS USED FOR ORNAMENTAL
TURNING AND OTHER PURPOSES, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
☑
I
The apparatus comprises a grinding wheel and a
wheel and a pedestal w
two rectilinear
and one circular movements for holding the different tools. The grinding wheel
may be of arkansas or other stone, of emery or corundum or of brass or other
metal supplied with a grinding powder, and oil; such metal wheels being partially
surrounded with a guard of metal to catch any of the said abrasive material or oil,
which may be thrown off from them. The wheel may be mounted to run between
centers or in a lathe, but by preference its spindle is carried horizontally, or it may.
be carried vertically or at any angle, in a bearing fixed on, a slide which has a
slight lateral reciprocatory motion, imparted to it by'a cam or eccentric worked by
a worm wheel driven by a pulley on a tangent screw, with the object of, causing.
an equal wear of the active surface of the grinding wheel. The same tangent,
screw spindle also drives the grinding wheel by means of a pair of bevil wheels
The pedestal to carry the tool consists of a longer slide at right angles to the
axis of the grinding wheel, which is traversed by a screw of 10 threads to the inch
provided with a micrometer, to read to decimal divisions of the inch. The upper i
portion of this slide carries a flat plate which rotates on a center towards the one.
end nearest the grinding wheel, and this end of the plate which is semicircular and
graduated both ways into degrees of a circle, also has its surface at a slightly lower
level, from à diametrical line passing, through its axis of rotation; and it is,
provided with a clamping screw to temporarily fix the plate at any required angle.
3.1..
71

page_text: At the opposite end and at a convenient distance from the axis of rotation, the
plate terminates in a vertical socket into which fits the stem of the receptacle or
tool box; the latter is raised or lowered by means of a rack on the stem actuated
by a toothed wheel fixed in the socket, and the stem is graduated to show the
cutting angle at which the tool is being ground, the stem may be. clamped by a
screw at the side of the socket. The receptacle or tool box itself is arranged to
receive tools, drills and cutters with stems of flat, square or other section and it also
receives a piece with a circular movement, having its axis in the direction of its
length, for shaping and grinding conical, triangular and other facetted tracing point
tools. The tool box is further provided with a power of horizontal traverse by a 1
slide, usually required parallel with that of the slide below at the base, which is
provided with a screw of 10 threads to the inch with a micrometer to read to
decimal divisions of the inch.
J.,&1
.
To shape and grind the cutting edges of round tools to accurate semicircles of
definite radii, the tool is first clamped in the tool box with its extreme end
precisely over the axis of rotation of the plate, as tested by a two legged steel
square temporarily applied upon the before mentioned lowered surface of the plate;
the tool box is then raised to the height that will grind the required cutting bevil,
and the pedestal is advanced by the lower slide until the tool touches the grinding
wheel, the lower slide is then withdrawn by its screw a quantity equal to the
required radius to be ground, and it thenceforth remains at that position, after which
adjustments the tool is readvanced into contact with the wheel by the upper slide,
and the pedestal is partially rotated upon the axis of the circular movement to
grind the perfect curvature.
To grind and shape angular tools, the circular movement is moved round to and
fixed at the required angle marked upon the semicircular edge, and the tool is
advanced to the grinding wheel by the lower slide, If the tool has a double facial
angle, when the one side has been ground as last described, the rotating plate is
then thrown over to the opposite side to the corresponding angle and refixed, after
which the tool is readvanced by the lower slide and' to precisely the same extent
as before, as determined by the revolutions of the screw and the divisions of the
micrometer, by which means the point of a double angular tool is ground exactly
centrally to the width of its stem. The cutting edges of flat and side cutting tools
are produced after the same manner; and conical, triangular and other facetted
tracing points by the complete or partial rotation of these tools within the tool
box.
:
In order that our said invention may be most fully understood and readily
carried into effect,
we will proceed to describe the drawing hereunto annexed,
1. "
DESCRIPTION OF THE DRAWING.
Figs 2 and 4 represent the complete machine in plan and side elevation; fig 3 a
front view of the pedestal and fig 1 a front view of the grinding wheel; a, a, a, is
the grinding wheel and its reciprocating frame and bearings; b, b, b, the tangent
screw and its' driving pulley which both rotates the grinding wheel and drives
the wormwheel and eccentric, c, c, c, to give the reciprocating movement..
d, d, is the tool box with its slide, screw and micrometer; e, e, the stem with
the rack and pinion by which it is raised or lowered; f. f, the rotating plate moving
on the center, g; h, h, is the lower slide, its screw and micrometer and i, i, is the
base of the machine.
E
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is
First. The combination of the pedestal with its two slides, its circular move-
ment and vertical adjustment for the shaping and grinding of any round tools to
accurate semi circular profiles by causing the tool to rotate upon the axis of its
fi

page_text: curvature; the shaping and grinding of any flat tools, angular or side cutting tools
and drills and of conical and facetted tracing points to definite forms both as to
their facial angles and cutting bevils; and also for grinding the points of double
angular tools precisely centrally to the widths of their stems or shafts.
Second. The combination of the reciprocatory motion given to the grinding
wheel by means of the tangent screw, wormwheel and eccentric or cam to equalize
the wear upon and to maintain the grinding wheel in condition for use.
Third. A compact machine for the purposes as hereinbefore described, which may
be used in combination with an ordinary lathe or as a distinct and separate
machine.