An Improved Machine for Shaping, Sizing, and Cutting or Sharpening the Drills of Rock Drills or other Tools.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
An Improved Machine for Shaping, Sizing, and Cutting or
Sharpening the Drills of Rock Drills or other Tools.
I, WALTER EDWARD KIMBER, Engineer, of Johannesburg, in the South African
Republic, at present residing at Steventon, in the County of Berks, England, do
hereby declare the nature of this invention to be as follows:-
This invention relates to an improved machine for shaping, sizing, and
cutting or sharpening, the drills of rock drills or other tools, in a more efficient
manner than has hitherto been effected, and with a great saving in labour, and
consequently in the cost of these operations.
The machine can be driven by steam or other power, and it consists broadly of
a frame composed of two uprights rising from the base plate. At the
upper end
of the uprights bearings are formed to receive a power shaft provided with fly-
wheels, and also fast and loose pulleys by which such shaft is driven.
The part of the power shaft between the uprights of the frame is made slightly
eccentric, the throw of the eccentric being but small, say 16th inch. The eccen-
tric revolves in a sleeve or sheave, the lower end of which is rounded, such
rounded part entering a hollow or recess formed in the upper end of a slide,
mounted so that it can move vertically in guides formed in the lower end of the
uprights of the frame. Springs rest on the base plate of the frame and bear
against the under side of each end of the slide, so as to force same upwards and
keep it in contact with the rounded end of the eccentric sleeve or sheave. The
connection between the slide and the eccentric sleeve or sheave thus forms a toggle
joint, and when the power shaft is actuated the eccentric thereon will cause the
slide to move up and down in the guideways in the uprights of the frame to the
extent of 1/8th inch.
The tools for shaping and sizing the drills are inserted between the lower end
of the slide and the upper surface of the base plate of the frame, the upper tool
being secured to such slide and the lower tool to the base plate of the frame.
When the tools are fixed in position, a sufficient space will be left between same
for the insertion of a bar of steel of the requisite thickness to form the drill, the
opposed surfaces of such tools having the necessary configuration to impart to
such bar the required form. When the bar. of steel is inserted between the tools
and the machine is started, the upper tool as it reciprocates with the slide will, by
its repeated blows upon such bar; squeeze or flatten same out.
The opening between the tools forms a taper with the smaller end at the back,
and another taper runs from near the centre of the tools to the front, the latter
taper not extending across the whole surface of the tools, but forming a groove,.
so that when the red hot steel is placed between the tools it will be flattened to
the same taper as the tools at the back end, the grooved part of the tools having
no effect whatever for the moment. The steel is then drawn forward until its

page_text: end is opposite the groove running from the centre of the tools to the front, when
a quarter turn is given to the bar, and the continued action of the upper tool
will reduce the width of the bar (which is continued to be pulled forward) until
the necessary reduction in width has been effected, and the drill thereby sized
and shaped as required. The first operation is therefore to flatten the drill, thus
expanding it in width, and the second operation, when it is placed on edge in the
taper groove and drawn towards the front, reduces the width to the necessary size.
When this has been effected the drill is again given a quarter turn and withdrawn.
It now remains to cut or sharpen the drill, and for this purpose I employ the
following mechanism. A top cutter is secured to the under side of the recipro-
cating slide, while an under cutter is mounted below same in the manner to be
hereinafter presently described. For the purpose of adjusting the upper cutter
so that its cutting surface or edge is in absolute alignment with that of the lower
cutter, I secure such cutter to the lower end of the slide by means of bolts and set
screws. If for instance the top cutter requires to be set a little more forward, the
bolts are slackened and the set screws then tightened, while if, on the contrary,
the cutter requires to be set further back, the set screws would be slackened and
the bolts then tightened.
The lower cutter is mounted in a holder or arm pivotted to the frame, and the
under surface of its forward end rests upon the upper surface of a wedge, which
can be moved in either direction so as to cause it to travel along a corresponding
incline in the bed of the frame. The movement is imparted to the wedge by
means of a pivotted lever acting in conjunction with an adjustable stop for the
purpose of regulating the extent of movement of such wedge and consequently
the height to which the holder of the lower cutter is raised when such wedge
is moved forward. When the lever is thrown back the wedge is withdrawn, and
the holder of the bottom cutter falls by its own weight, carrying such cutter
with it away from the upper cutter.
The object of making the bottom cutter capable of rising and falling at will is,
firstly, that as the top cutter only descends 8th inch for each stroke, it would
be impossible. to cut anything off of greater thickness if the bottom cutter was
a fixture, while if the slide was allowed a greater stroke it would not be powerful
enough to compress the steel in the operation of shaping and sizing, without
having resort to the employment of gear wheels such as are employed in punching
and shearing machines. Further, if drills or like tools are hammered by sharp
quick blows it improves the lasting qualities of the steel, and it will therefore
be seen that by raising the bottom cutter and holding it in position while the
top cutter ascends and descends rapidly, the cutting process is accomplished by a
succession of sharp, quick, decisive blows, which also improves the cutting edge
of the drill. In the third place as the bottom cutter drops free from the top
cutter when not in actual use, the edges are saved from becoming blunt and also
have an opportunity of cooling.
It will be readily understood that the operation of sharpening or cutting the
drill is effected by inserting the portion of the drill to be cut or sharpened
between the two cutters, then raising the lower cutter by operating the pivotted
lever, and the action of the upper cutter as it ascends and descends in con-
junction with the action of the lower cutter, will remove the portion of metal
which is requisite to sharpen such surface.
It will also be readily understood that the machine may be employed either for
forming and sharpening new drills or other tools, or for re-sharpening drills or
other tools which have been already employed.
Dated this 4th day of December 1897.

page_text: An Improved Machine for Shaping, Sizing, and Cutting or
Sharpening the Drills of Rock Drills or other Tools.
I, WALTER EDWARD KIMBER, Engineer, of Johannesburg, in the South African
Republic, at present residing at Steventon, in the County of Berks, England, 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 relates to an improved machine for shaping, sizing, and
cutting or sharpening, the drills of rock drills or other tools, in a more efficient
manner than has hitherto been effected, and with a great saving in labour, and
consequently in the cost of these operations.
The machine can be driven by steam or other power, and a suitable form of
constructing same is illustrated in the accompanying drawings, in which
Fig. 1 is a side elevation partly in section of such machine,
Fig. 2 an end elevation of same,
Figs. 3 and 4 respectively a side and end elevation of the shaping and sizing
tools,
Fig. 5 a vertical section through the cutting or sharpening tools, and
Fig. 6 a plan view of Fig. 5.
The machine consists broadly of a frame composed of two uprights A A rising
from a base plate A'. At the upper end of the uprights A A bearings B are
formed to receive a power shaft C provided with fly-wheels 1 D, and also fast
and loose pulleys E E by which such shaft is driven.
The part of the shaft C between the uprights A A is made slightly eccentric
as shown at c, the throw of the eccentric being but small, say 1/16th inch. The
eccentric c revolves in a sleeve or sheave F, the lower end of which is rounded as
shown at f, such rounded part entering a hollow or recess g, formed in the upper
end of a slide G, mounted so that it can move vertically in guides formed in the
lower end of the uprights A A. Springs H H rest on the base plate A¹ and bear
against the under side of each end of the slide G, so as to force same upwards and
keep it in contact with the rounded end f of the eccentric sleeve or sheave F.
The connection between the slide G and the eccentric sleeve or sheave F thus
forms a toggle joint, and when the power shaft C is actuated the eccentric c will
cause the slide G to move up and down in the guideways in the uprights A A
to the extent of 1/8th inch.
The tools for shaping and sizing the drills are inserted between the lower end
of the slide G and the upper surface of the base plate A' of the frame, the upper
tool I being secured to such slide G and the lower tool I' to the base plate AT of
the frame. When the tools I I' are fixed in position, a sufficient space will be
left between same for the insertion of a bar of steel of the requisite thickness to
form the drill, the opposed surfaces of such tools having the necessary configura-
tion to impart to such bar the required form. When the bar of steel is inserted
between the tools and the machine is started, the upper tool I as it reciprocates
with the slide G will, by its repeated blows upon such bar, squeeze or flatten
same out.
It will be seen in Figs. 3 and 4 that the opening between the tools forms a taper
with the smaller end at the back, and that another taper runs from near the
centre of the tools to the front, the latter taper not extending across the whole
surface of the tools, but forming a groove as shown by the dotted lines, so that

page_text: when the red hot steel is placed between the tools it will be flattened to the same
taper as the tools at the back end, the grooved part of the tools having no effect
whatever for the moment. The steel is then drawn forward until its end is
opposite the groove running from the centre of the tools to the front, when a
quarter turn is given to the bar, and the continued action of the upper tool will
reduce the width of the bar (which is continued to be pulled forward) until the
necessary reduction in width has been effected, and the drill thereby sized and
shaped as required. The first operation is therefore to flatten the drill, thus
expanding it in width, and the second operation, when it is placed on edge in the
taper groove and drawn towards the front, reduces the width to the necessary
size. When this has been effected the drill is again given a quarter turn and
withdrawn.
It now remains to cut or sharpen the drill, and for this purpose I employ the
mechanism shown in detail in Figs. 5 and 6. It will be seen that a top cutter K
is secured to the under side of the reciprocating slide G, while an under cutter K¹
is mounted below same in the manner to be hereinafter presently described. For
the purpose of adjusting the upper cutter K so that its cutting surface or edge
is in absolute alignment with that of the lower cutter K¹, I secure such cutter
to the lower end of the slide G by means of bolts k, and set screws k¹. If for
instance the top cutter requires to be set a little more forward, the bolts k are
slackened and the set screws then tightened, while if, on the contrary, the
cutter requires to be set further back, the set screws k¹ would be slackened and
the bolts then tightened.
The lower cutter K¹ is mounted in a holder or arm L pivotted to the frame at
as shown, and the under surface of its forward end rests upon the upper surface
of a wedge M, which can be moved in either direction so as to cause it to travel
along a corresponding incline in the bed A. The movement is imparted to the
wedge M by means of a pivotted lever N acting in conjunction with an adjustable
stop O for the purpose of regulating the extent of movement of such wedge and
consequently the height to which the holder L of the lower cutter K is raised
when such wedge is moved forward. When the lever is thrown back the wedge
is withdrawn, and the holder L of the bottom cutter K¹ falls by its own weight,
carrying such cutter with it away from the upper cutter K.
The object of making the bottom cutter capable of rising and falling at will is,
firstly, that as the top cutter only descends th inch for each stroke, it would be
impossible to cut anything off of greater thickness if the bottom cutter was a
fixture, while if the slide was allowed a greater stroke it would not be powerful
enough to compress the steel in the operation of shaping and sizing, without
having resort to the employment of gear wheels such as are employed in punch-
ing and shearing machines. Further, if drills or like tools are hammered by
sharp quick blows it improves the lasting qualities of the steel, and it will there-
fore be seen that by raising the bottom cutter and holding it in position while
the top cutter ascends and descends rapidly, the cutting process is accomplished
by a succession of sharp, quick, decisive blows, which also improves the cutting
edge of the drill. In the third place as the bottom cutter drops free from the
top cutter when not in actual use, the edges are saved from becoming blunt and
also have an opportunity of cooling.
It will be readily understood that the operation of sharpening or cutting the
drill is effected by inserting the portion of the drill to be cut or sharpened
between the cutters K K', then raising the lower cutter by operating the lever N,
and the action of the upper cutter K as it ascends and descends in conjunction
with the action of the lower cutter K' will remove the portion of metal which is
requisite to sharpen such surface.
It will also be readily understood that the machine may be employed either
for forming and sharpening new drills or other tools, or for re-sharpening drills
or other..tools which have been already employed.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
In a machine for shaping, sizing, and cutting or sharpening the drills of rock
drills or other tools
1. The combination with an eccentric shaft driven by steam or other power
and revolving within a sheave or sleeve the lower end of which engages the
upper end of a vertical slide, of shaping and sizing tools secured respectively to
the lower end of the slide and to the base plate or bed of the frame of the machine,
and of cutting or sharpening tools, one of which is secured to the lower end of
such slide while the other is mounted in a holder pivotted to the frame and
actuated by means to enable same to be moved towards or away from the upper
cutter, all substantially as and for the purposes specified.
2. The combination with a vertically reciprocating slide of shaping and sizing
tools, one of which is secured to the lower end of the slide while the other is
supported in the base plate or bed of the frame of the machine, such tools being
formed with a taper opening between them with the smaller end of the taper at
the back, and also with another taper running from near the centre of the tools
to the front thereof, but not extending across the whole surface of such tools,
all substantially as specified, and as shown in the accompanying drawings.
3. The combination with a vertically reciprocating slide of cutting or sharpen-
ing tools, one of which is secured to the lower end of such slide, preferably in such
a manner that same may be adjusted forward and backward as desired, and of
a lower cutter mounted in a pivotted arm or holder the forward end of which
rests upon a wedge working in conjunction with a corresponding inclined surface
in the bed or frame of the machine, and operated by a pivotted lever, all sub-
stantially as and for the purpose specified.
Dated this 5th day of September 1898.