Improvements in Drill Shaping and Sharpening Machines.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Drill Shaping and Sharpening Machines.
I, GEORGE CROYDON MARKS, of 18, Southampton Buildings, Chancery Lane,
London, W.C., Consulting Engineer, (a communication from Alfred Smith, of
Johannesburg, South African Republic, Smith), do hereby declare the nature of
this invention to be as follows:--
My invention relates to a drill shaping and sharpening machine specially to
star drills such as are used in mining and quarrying operations.
The object of my invention is to speedily and accurately shape and sharpen
such tools at the mine or quarry without the necessity for skilled hand labour.
My machine consists of a suitable framing carrying two or more rollers or
discs geared to each other, the said rollers having opposing dies recesses or pro-
jections cut in their surfaces so shaped as to form the end of the drill, or steel,
when the steel from which the tool is to be formed, is passed through the rollers.
The steel is heated to a sufficiently high temperature to enable it to be dealt
with by the rollers, which may be driven by steam or hand power as may be
desired. The dies, recesses or projections on the opposing rollers are arranged
to produce the necessary configuration of the drill, and adjustable cutters or cut-
ting edges are sometimes applied to cut away the superfluous metal and leave
the edges of the drills in a sharp condition suitable for work.
When the star pointed drill, used in many drilling machines, is to be formed
and sharpened, four rollers are required, two of which work horizontally and two
vertically, and they are pressed or forced together either by weights and levers,
or screws and suitable gaps are formed to pass the drill as well as to form or cut
the point. The moulds, or dies are preferably made eccentric so that when the
rollers are in a position for working, a drill may be passed between them until
it touches a stop or gauge: the rollers are then revolved from the gauge, the dies
gradually nip the drill or hot steel and carry it forward, moulding and sharpen-
ing the point until, on passing the centre the waste portion of the steel is cut
away by the cutting edges, leaving a perfectly shaped cutting edge on the drill
or steel.
Improvements in Drill Shaping and Sharpening Machines.
I, GEORGE CROYDON MARKS, of 18, Southampton Buildings, Chancery Lane.
London, W.C., Consulting Engineer, (a communication from Alfred Smith, of
Prise 8dl

page_text: belting from any suitable source and which carries a fly wheel whereby energy
may be accumulated for the purpose of easy and effective working.
The rollers B B have each one or a series of recesses H provided circumferen-
tially upon their peripheries of a shape corresponding to the drill into which the
drill may be introduced for shaping and sharpening; and within these recesses
dies I are provided of suitable shape for the formation of the point of the drill J
into the actual form desired. The recesses H are prolonged beyond the rear
edge of the die at H¹ in order to receive the superfluous metal that is nipped
off; while in the opposite direction the recesses gradually grow shallow until
they issue upon the periphery of the roller. The dies I are preferably of the
shape illustrated in Figures 3 and 4 of the drawings. Their bases are let into
dovetail grooves formed to receive them upon the rollers and are capable of being
introduced or withdrawn for renewal or repair by means of intermediate grooves 133
(Figure 6) which upon the dies being laterally thrust forward therein can be
withdrawn but when the dies are fixed in position packing blocks K are intro-
duced into the grooves B and are held in position by means of screws K'.
Stop gauges L Figures 1, 2, 3, 7, and 8 are mounted in a frame M and in posi-
tion immediately in line with the recesses H and die I. These stop gauges L
act under the action of spiral springs L¹ which encircle them and abut against
the collar La secured thereto so that they may be forced back slightly for the
purpose of accommodating the drill that is introduced to abut against them to
an extent determined by the amount of metal which the workman intends to
cut away from the extremity of the tool.
In operation the rollers rotate in the direction indicated in Figure 3 and as
the recesses are opening out the extremity of the drill J is introduced to abut
against the stop gauge L thereupon the dies I come together and compress the
extremity of the tool and nip off any superfluous metal and the tool is then with-
drawn and tempered.
In the drawing three recesses and three sets of dies are shown for operation
upon three tools simultaneously, but it is obvious that one or any other number
of dies may be employed.
For the purpose of accurately adjusting the register of the rollers 13 131 so that
the cutting edge of the dies I may coincide upon rotation, means are provided that
are illustrated in Figures 9 and 10 consisting of a transverse arm N which passes dia-
metrically through the spindle 6 of the roller B', the gear wheel P by means of
which motion is communicated to the lower roller by engagement with a corre-
sponding gear wheel secured upon the spindle of the lower roller B has provided
upon its face lugs through which adjusting screws ppl are caused to pass
by means of which the angular position of the spindle and roller B₁ may be
adjusted in relation to the wheel P within narrow limits so as thereby to adjust
the opposing dies into coincidence.
For convenience in dressing and finishing the tool after shaping and sharpen-
ing an emery disc Q (Figure 11) having a conical face q may be fitted in position
upon the extremity of the shaft H* (Figure 1). The emery disc Q is fitted within
a boss Q against which it is retained by means of a screw and washer q¹² the
boss Q being in turn secured to the extremity of the shaft by means of a set
screw ³.
It is obvious that the ultimate shape of the drill point is determined by the
shape of the dies and that any suitable shape may be employed other than that
illustrated without departing from the invention.
In carrying the invention into effect in the production of a machine for shaping
and sharpening a star pointed drill as illustrated in Figures 12 to 16 of the
drawings four rollers or cutters SS, TT are employed having peripheries of
V shape, two of which TT work horizontally and two SSI vertically. The
rollers or cutters S S¹ are mounted upon horizontal spindles VV which are carried
within bearings W W, & W & W3 respectively, which are fixed to the lateral
frames XX supporting the mechanism. Gear wheels YY' are mounted upon

page_text: the provision of bevil wheels integral therewith or applied thereto substantially
as hereinbefore described with reference to Figure 12 of the drawings.
10, A drill shaping and sharpening machine substantially as hereinbefore
described and as illustrated in Figures 12 to 16 of the accompanying drawings.
11, A drill shaping and sharpening machine substantially as herein before
described