IMPROVEMENTS IN ROCK PERFORATING MACHINES
Year: 1883

page_text: LETTERS PATENT to Martin Macdermott of 25 and 26 Pudding Lane in the
City of London Architect and William Glover of the Albert Iron Works,
Saint James' Road Bermondsey Engineer for an Invention of “IMPROVEMENTS
IN ROCK PERFORATING MACHINES"
PROVISIONAL SPECIFICATION left by the said Martin Macdermott and
William Glover at the Office of the Commissioners of Patents on the 5th July
1883.
MARTIN MACDERMOTT of 25 and 26 Pudding Lane in the City of London
Architect and WILLIAM GLOVER of the Albert Iron Works Saint James' Road
Bermondsey Engineer "IMPROVEMENTS IN ROCK PERFORATING MACHINES
"
This invention has for its object improvements in machines in which hand labour
is employed for boring rocks by percussion.
The frame of the machine contains a tubular carrier to which a reciprocating
movement is imparted in the manner described in the specification of a former
Patent granted to us N° 4008 in the year 1881 that is to say the carrier has at its
end a roller and cam projections on the face of a rotating disc or plate operate
against the roller drawing the carrier towards the axis of the plate cam and then
releasing it and admitting of the return motion being effected by a spring. Usually
it is convenient to employ two of these plate cams one on either side of the carrier.
The axes of the plate cams are furnished with fly wheels and handles. The carrier
bas a collar upon it against which a coiled spring contained in a spring box forming
part of the frame abuts. The carrier also at its inner end (or that furthest from
the plate cams) is enlarged into a box in which a nut is contained and a tube with
a screw thread upon it passes through the carrier from end to end and through this
nut. Within the screw again the drill bar is carried in such a manner that it is
free only to turn, it partakes of the reciprocating motion which the tubular screw
receives through the nut in the box at the end of the carrier. At each reciprocation
the end or edge of the drill bar strikes upon the rock. In the latter part of the
stroke a trigger mounted upon the carrier upon the side of the nut box comes into
[Price Rd1

page_text: contact with a stationary tappet upon the frame. The trigger then gives move-
ment to a lever carrying a pawl engaging with a ring of ratchet teeth upon the
nut. A spring connected with the pawl lever brings this lever back during the
return stroke of the machine and turns the nut thereby advancing the hollow screw
and the drill bar. The amount of the advance depends upon the distance the drill
penetrated at the last impact for the trigger is operated upon only in the latter
part of the stroke and if the stroke is brought to an early conclusion by the
The screw is
resistance of the rock the trigger is moved but little or not at all.
prevented from turning with the nut by a feather or tooth entering a groove cut
longitudinally in the screw. This feather or tooth is in the collar upon the carrier
against which the spring abuts, it is capable of being retracted out of the groove in
the screw for a purpose to be explained further on. In the interval between the
strokes which the drill bar is thus caused to make against the face of the rock it is
necessary that the drill bar should be turned partly round so that the edge of the
drill bar may not always strike in the same place.
.
This is effected by means of a bevilled pinion upon the head of the bar engaging
with another similar pinion upon the same axis with a ratchet the edge of the cam
plate is itself made into a cam and it operates to move a bell crank lever acting
with this ratchet and bevilled gearing.
When the hole in the rock has been drilled to the full depth required the drill
bar has to be run back out of the hole and to effect this conveniently the drill bar
is connected with, the screw through, which, it passes. By shooting a small bolt
provided for this purpose at the same time the feather or tooth which prevents the
Screw turning is withdrawn and then the drill bar can be turned by means of a
handle applied at its upper end and the desired.result attained..
::

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Martin Macdermott and William Glover in the Patent Office on
the 5th January 1884.
MARTIN MACDERMOTT of 25 and 26 Pudding Lane in the City of London
Architect and WILLIAM GLOVER of the Albert Iron Works Saint James', Road,
Bermondsey, Enginéer "IMPROVEMENTS IN ROCK PERFORATING. MACHINES
"
This invention has for its object improvements in machines in which hand labour
is employed for boring rocks by percussion.
The annexed drawings show a rock perforating machine constructed in accordance
with the invention.
Figure 1 is a side elevation with some of the parts.removed.
Figure 2 is a front elevation partly in section.
The frame a of the machine contains a tubular carrier b to which a reciprocating
movement is imparted. The carrier has at its end a roller and cam projections on
the face of a rotating disc or plate operate against the roller, drawing the carrier
towards the axis of the plate cam, and then releasing it and admitting of the return
motion being effected by a spring. Usually it is convenient to employ two of these
plate cans one on either side of the carrier.
In the drawings d is the axis to which the handles are applied e. e. are the plate
cams and el. e. the cam projections upon them.
The axis of the plate cans is furnished with fly wheels. The carrier b has a
collar 6' upon it against which a coiled spring of contained in a spring box a*
forming part of the frame a abuts. The carrier also at its inner end (or that
furthest from the plate cams) is enlarged into a box b* in which a nut h is
contained and a tube i with a screw thread upon it passes through the carrier b
from end to end and through the nut h. Within the tubular screw i the drill
bar j is carried in such a manner that it is free only to turn it has on it at one end
a socket j' in which the tool j* is clamped. Also beyond the screw i in the opposite
direction the drill bar j has a collar j² fixed upon it.
The drill bar partakes of the reciprocating motion which the tubular screw i
receives through the nut in the box 6x at the end of the carrier. At each
reciprocation the end or edge of the tool carried by the drill bar strikes upon the
rock. In the latter part of the stroke a trigger k mounted upon the carrier upon
the side of the nut box 6x comes into contact with a stationary tappet l. upon the
frame a. The trigger then gives movement to a lever m carrying a pawl engaging
with a ring of ratchet teeth upon the nut h. A spring connected with the pawl
lever brings this lever back during the return stroke of the machine and turns the
nut thereby advancing the hollow screw i the drill bar j and the drill jx. The
amount of the advance depends upon the distance the drill penetrated at the last
impact for the trigger is operated upon only in the latter part of the stroke and
if the stroke is brought to an early conclusion by the resistance of the rock the
trigger is moved but little or not at all. The screw i is prevented from turning
with the nut h by a feather or tooth b'x entering a groove cut longitudinally in
the screw.
This feather or tooth is in the collar b¹ upon the carrier b against
which the spring fabuts, it is capable of being retracted out of the groove in the
screw for a purpose to be explained further on. In the interval between the strokes
which the drill bar jis thus caused to make against the face of the rock it is
Decessary that the drill bar should be turned partly round so that the edge of the
drill or tool j* may not always strike in the same place. This is effected by means
of a bevilled pinion p upon the head of the bar j engaging with another similar

page_text: pinion q¹ upon the same axis q with a ratchet wheel q². The edge of the cam
plate e is itself made into a cam at e* as the drawing shows and it operates to
move a bell crank lever r driving by means of a pawl s.this ratchet q² and bevelled
gearing.
When the hole in the rock has been drilled to the full depth required the drill
bar has to be run back out of the hole and to effect this, conveniently the drill
bar, is connected with the screw through which it passes by shooting a small
bolt t provided for this purpose. At the same time the feather or tooth 61* which
prevents the screw turning is withdrawn and then the drill bar can be turned
by means of a handle applied at its upper end and the desired result attained:
Having thus described the nature of our said. invention 'and the manner of
. performing the same we would have it understood that we claim-
-
First Our improved rock perforating machine substantially as described.
Second-The means for rotating the drill bar consisting of an additional
cam surface ex formed upon the plate came which imparts the reciprocating
movement.
Third The means for rapidly rotating the screw i to withdraw the drill bar j
by locking the screw fast with the drill bar freeing it from the carrier 6 and then
rotating the drill bar substantially as described.
Fourth-The feed gear substantially as described.
In witness whereof I the said Martin Macdermott have hereunto set my
hand and seal this first day of January in the year of our Lord One thousand
eight hundred and eighty four.