IMPROVE- MENTS IN ROCK-BORING MACHINES
Year: 1883

page_text: LETTERS PATENT to Edward Thomas Hughes of the firm of Hughes and Son,
Patent Agents, N° 5 Chancery Lane, London, for an Invention of "IMPROVE-
MENTS IN ROCK-BORING MACHINES" communicated to him from abroad by
William Frederick Heshuysen, of Amsterdam, Holland.
PROVISIONAL SPECIFICATION left by the said Edward Thomas Hughes at
the Office of the Commissioners of Patents on the 20th September 1883.
EDWARD THOMAS HUGHES of the firm of Hughes and Son, Patent Agents,
N° 5 Chancery Lane, London, "IMPROVEMENTS IN ROCK-BORING MACHINES
A communication to me from abroad by William Frederick Heshuysen of
Amsterdam, Holland.
و"
My Invention relates to improvements in the feed or advance of the drill
employed in Rock-boring Machines.
On the accompanying Drawing,
Figure 1 is a horizontal section of this improved feeding apparatus.
a is the drill bar, ba tube in which the drill bar freely works. c is a circular
block fixed on the tube b. d is a circular disc through the centre of which passes
the drill bar a, and is attached to the block c by means of small bars i. i. which
bars regulate the distances between the block cand circular disc d. e is the working
axle, on which are fixed the principal cam f two auxiliary cams g. g. and two
wedges h. h. attached to the disc d sliding along the drill bar a.
Figures 2 and 3 are views of the two auxiliary cams g. g. and the principal cam f
respectively; and Figure 4 a cross section, showing the drill bar a, disc d, block c
with the tube b, and the centres of the cams ƒ and g. g. fixed on the working
axle e.
The action of the machine is as follows:-
:-
The working axle e being rotated by means of hand or any other power on the
left hand side, the block c is forced backwards a short distance say of an inch,
by the two auxiliary cams g. g., the peculiar form of these cams keeping the block
in position; the principal cam f then forces the discd with the wedges h. h. towards
the block c.

page_text: The moment that the wedges act on the drill bar, they grip it firmly and hold it
as in a vice, the drill bar a, disc d, and block c with the tube b forming one solid
mass. Following the rotation of the working axle e the motive power (whether air,
spring or otherwise) will act on the dril bar a, the moment the principal cam f
leaves the disc d. Power then being exerted on the whole solid mass, it strikes the
rock or the material to be perforated.
The shock of the drill on the rock disengages the wedges, and leaves the drill bar
entirely free, while all the other parts resume their former positions, and are ready
to act again in the same manner as described, at the next half revolution of the
working axle.
Consequently if the resistance offered by the material to be perforated is less of
an inch at each blow of the drill, the drill will always remain at the bottoin of the
socket at each half revolution of the working axle. Thus by this arrangement, the
feeding or advance of the drill is absolutely automatic according to the resistance
offered by the material to be perforated, that is to say, the drill bar a being
perfectly free after each blow, remains at the bottom of the socket, and is only
raised when the disc d being forced backwards of an inch, the pressure on the
block causes the wedges g. g. to act on the drill bar. The bluck c has been
previously forced back by the two auxiliary caus g. g. and the drill bar has thus
been lengthened inch at each half revolution of the working axle e.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edward Thomas Hughes in the Patent Office on the 20th March
1884.
EDWARD THOMAS HUGHES of the Firm of Hughes and Son, Patent Agents,
5 Chancery Lane, London "IMPROVEMENTS IN ROCK-BORING MACHINES." A com-
munication to me from abroad by William Frederick Heshuysen, of Amsterdam,
Holland.
My Invention relates to improvements in the feed or advance of the drill
employed in Rock-boring machines.
On the accompanying Drawing, Figure 1 is a horizontal section of this improved
feeding apparatus.
a is the drill bar, b a tube in which the drill bar freely works, c a circular block
fixed on the tube b-d a circular disc through the centre of which passes the drill
bar a, and is attached to the block c by means of small bars i. ., which bars
regulate the distances between, the block c and circular disc d. e is the working
axle, on which are fixed the principal cam f two auxiliary cams g. g. and two
wedges h. h. attached to the disc d, sliding along the drill bar a.
Figures 2 and 3, are views of the two auxiliary cams g. g. and the principal cam f
respectively, and Figure 4 a cross section, shewing the drill bar a, disc d, block c
with the tube b, and the centres of the cams f and g. g. fixed on the working
axle e.
The action of the machine is as follows:-
The working axle e being rotated by means of hand or any other power on the
left hand side, the block c is forced backwards a short distance say of an inch,
by the two auxiliary cams g. g, the peculiar form of these cams keeping the block
in position, the principal cam f then forces the disc d with the wedges h.h. towards
the block c.
The moment that the wedges act on the drill bar, they grip it firmly and hold
it as in a vice, the drill bar a, disc d, and block c with the tube b, forming one solid
mass. Following the rotation of the working axle e, the motive power (whether air,
spring or otherwise) will act on the drill bar a, the moment the principal cam f
leaves the disc d. Power then being exerted on the whole solid mass, it strikes the
rock or other material to be perforated. The shock of the drill on the rock disengages
the wedges and leaves the drill bar entirely free, while all the other parts resume
their former positions, and are ready to act again in the same manner as described,
at the next half revolution of the working axle.
Consequently if the resistance offered by the material to be perforated is less of
an inch at each blow of the drill; the drill will always remain at the bottom of the
socket at each half revolution of the working axle. Thus by this arrangement the
feeding or advance of the drill is absolutely automatic according to the resistance
offered by the material to be perforated, that is to say, the drill bar a, being
perfectly free after each blow, remains at the bottom of the socket, and is only
raised when the disc d being forced backwards of an inch, the pressure on the
block c causes the wedges g. g. to act on the drill bar. The block c has been
previously forced back by the two auxiliary cams g. g. and the drill bar has thus
been lengthened of an inch at each half revolution of the working axle e.
Having thus described the nature of my Invention and shewn by drawings how
the same is to be performed, I would have it understood that I claim :-
Firstly. The cams g for pushing backwards the block c after each forward motion
of the drill.

page_text: Secondly. The cam f operating on the block d and gripping jaws h by the
combined action of which the bar is gripped in a different place after each stroke.
Thirdly. The general construction of apparatus for feeding the drill bar at a rate
proportional to its perforating power, substantially as herein shewn and described.
In Witness Whereof I the said Edward Thomas Hughes have hereunto set my
hand and seal this nineteenth day of March in the year of our Lord One
thousand eight hundred and eighty four.
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