IMPROVEMENTS IN ROCK DRILLING MACHINES, PARTS OF WHICH INVENTION ARE APPLICABLE TO OTHER MACHINERY
Year: 1875

page_text: ETTERS PATENT to George Haseltine, of the "International Patent
Office," Southampton Buildings, London, Doctor of Laws, for the
Invention of "IMPROVEMENTS IN ROCK DRILLING MACHINES, PARTS OF
WHICH INVENTION ARE APPLICABLE TO OTHER MACHINERY." -A communi-
cation from abroad by Edward Stevens Winchester, of Boston, and
Henry Willis Phelps, of Springfield, both in the State of Massa-
chusetts, United States of America.
COMPLETE SPECIFICATION filed by the said George Haseltine at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 9th February 1875, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HASELTINE, of the "International Patent Office," Southampton
Buildings, London, Doctor of Laws, send greeting.

page_text: WHEREAS I am in possession of an Invention for
IMPROVEMENTS
IN ROCK DRILLING MACHINES, PARTS OF WHICH INVENTION ARE APPLICABLE TO
OTHER MACHINERY," and have petitioned Her Majesty to grant unto me,
my executors, administrators, and assigns, Her Royal Letters Patent
for the same, and have made solemn Declaration that it has been
communicated to me from abroad by Edward Stevens Winchester, of
Boston, and Henry Willis Phelps, of Springfield, both in the State of
Massachusetts, United States of America.
NOW KNOW YE, that I, the said George Haseltine, do hereby declare
that the following Complete Specification, under my hand and seal, fully
describes and ascertains the nature of the said Invention, and in what
manner the same is to be performed in and by the following state-
ment, reference being had to the accompanying Drawings forming a
part of this Specification :-
In the present construction of steam hammers, rock drills, and other
engines, where mechanism directly connected with the piston is employed
for giving a blow, it is customary to place the packing around the piston
and attach it thereto, to prevent the leakage of steam or air between
it and the cylinder. This construction is objectionable for the reason
that the concussion is communicated to the packing which soon becomes
broken, rendering it necessary to remove the same, and to substitute a
new packing therefor, which involves the loss of considerable time and
labor. To obviate the above mentioned difficulty is the purpose of this
Invention, which consists, first, in placing the packing within a groove
extending around the interior of the cylinder in contradistinction to
attaching it to the piston as heretofore, the cylinder being either made
in sections for the reception of a continuous packing, or in one piece
for the reception of a packing formed in sections, or the cylinder may
be bored out large enough to receive a packing made in a single piece
kept in place by a bushing or sleeve extending from it to the cylinder
head, a piston being employed of such length that it will not pass out
of contact with the packing during any portion of the stroke, by which
construction the packing is allowed to remain at rest and the con-
cussion received by the piston is kept from being communicated
thereto.

page_text: the cylinder for a projection on the piston to strike against, in order to
cushion the blow in either direction.
And the said Invention furthermore consists in interposing an elastic
washer or spring between a projection or shoulder on the feed screw and
the plate by which its rear end is supported, in order to relieve the 5
screw from the jarring and concussion to which it would otherwise be
subjected by the movement of the piston.
PP
drill engine constructed in accordance with this Invention representing 1
the manner of applying the packing thereto.
Figure 2 is a perspective view of the piston and a portion of its rod.
Figure 3 is a longitudinal section through the centre of the portion
of the cylinder, shown in Figure 1, with the piston, shown in Figure 2,
applied thereto.
Figure 4 is a perspective view of a portion of one of the sections of
which the cylinder is composed.
Figure 5 is a longitudinal section through a cylinder, illustrating in
its construction a modification of this Invention.
1
Figure 6 is a longitudinal section of a cylinder of somewhat different-2
construction, showing the valve, steam passages, and ports with the
piston in elevation.
Figure 7 is a longitudinal section through the piston shown in Figure 6;
Figure 8 is an end view of the same.
Figure 9 is a section representing a valve of somewhat different con- 2
struction to that shown in Figure 6, applied to the cylinder of a rock drill
engine.
Figure 10 is an enlarged section of the valve shown in Figure 9
(detached).
.
Figure 11 is a sectional elevation representing the feeding and g
rotating devices of a rock drill engine, constructed in accordance with
this Invention; Figure 12 is a rear elevation of the same.

page_text: Figure 13 is a sectional elevation representing the device employed
for cushioning the blow of the piston in either direction.
In Figures 1, 2, 3, and 4, A represents the cylinder of a rock drill
engine cut longitudinally through the centre and composed of three
sections a, b, c, two outer sections a and c, and a middle section b. The
inner ends of the outer sections a, c, are provided with projecting lips
or flanges 20 which fit into corresponding grooves 21 (Figure 4) in the
outer ends of the middle section b, the several sections snugly fitting
into or overlapping each other, by which construction they are kept
from separating laterally, while bolts B passing through the entire
length of the three sections prevent their longitudinal separation, and the
union of their surfaces is thus effected in such manner as to insure a
tight joint as required. The interior surface at both ends of the section b.
is recessed out in order that when the several sections are properly united
and secured together, annular grooves d may be formed therein of a
width sufficient to receive the packing rings h for preventing the escape
of steam between the cylinder and the piston C, which is made of
sufficient length to extend over both packing rings in any position of
the piston during any portion of its stroke. Channels i, i, cut in the
inner surface of each of the outer sections a, c, of the cylinder, and
extend to the packing and down the sides of each of the grooves d in
which it is placed, the purpose of the channels being to allow of steam
being conducted under the packing to force it snugly up and around the
piston, whereby all leakage between it and the cylinder is avoided.
From the foregoing it will be seen that owing to the packing being
placed within the cylinder it remains permanently in one position, where
the concussion received by the piston cannot be communicated thereto,
and consequently the frequent breaking of the packing incident to the
former construction, where it was attached to the piston, is entirely
avoided. This method of constructing the cylinder in sections, and
making the joints at the points where the recesses for the packing arc to
be located, simplifies and cheapens its construction, as by this plan the
joint for the union of the sections and the recess for the packing ring
can both be turned with ease in a lathe without removing the sections.
The groove 21 for the joint and the recess d for the packing, both being
at the end of the section, are easily accessible by ordinary tools. With
equal facility the lips or flanges 20 can be formed on the other sections
by simply turning off their outer surfaces in a lathe.

page_text: It is obvious that any number of sections and of packing rings may
be used, but in all cases the length of the piston should be such that its
ends will not pass the rings.
Where a single packing ring is employed, the cylinder requires to be
made in two sections only, the groove being formed at their junction.
In this manner we are enabled to construct an engine that is especially
adapted for use with rock drills, steam hammers, and the like, and
that will remain in order much longer than those heretofore in use,
and which at the same time is very simple and cheap to construct.
Instead of making the cylinder in sections for the reception of a con-
tinuous packing, the said cylinder may be made in one piece, provided
with one or more grooves for the reception of a packing formed and
introduced in sections.
Figure 5 represents a modification in which the cylinder A is con-
structed in a single piece, and is bored out to receive a packing ring 22, 1
made in a single piece, and kept in place by a bushing or sleeve 23
extending therefrom to the cylinder head.
2
In Figure 6 the cylinder A¹ is made with an opening centrally.
on one side, over which is formed a steam chamber B¹, that may be
complete or formed by bolting in a cap, as represented. The steam
passages, as shown in the Drawing, extend from near the ends of
the cylinder, and terminate in ports c¹ and o¹ on the inner walls of
the chamber B¹, near its apex, one on each side, this portion of the
chamber having on its inner face the form of an arc of a circle, and
being made true and smooth. Within the chamber B¹ is pivoted 2
an oscillating valve I, which is provided with two radial wings
and ¹, as represented in Figure 6, these wings constituting the valves.
proper to close and open the ports c₁ and o¹. From the valve I' a
lever b¹ extends inward through the opening in the cylinder to near its
centre, where it rests loosely in a recess or groove extending around the 3
piston P¹ at its centre, and by which the valve is operated by the move-
ment of the piston. The steam or air is admitted to the chamber B¹
through a pipe C', which may enter the chamber at any point under-
neath the valve or between it and the piston, and escapes through a
hole D¹.
3

page_text: When engines of this class are used for drilling in mines or tunnels,
and similar places under ground, they are often operated by compressed
air instead of steam, and as heretofore constructed much difficulty has
arisen from the formation of ice in or about the pipes or passages
through which the air escapes after having performed its work, in con-
sequence of its sudden expansion on being liberated, and its absorption
of heat from surrounding objects, in accordance with well-known laws.
It will be observed that by the arrangement of valve and exit port,
shown in Figure 6, the air escapes from the valve chest when liberated
by simply passing out through the hole D¹, no pipe or passage being
used beyond this hole, and thus this difficulty is obviated. By keeping
the central space around the piston filled with live steam or air there
will be no escape of steam or air from the ends of the piston into the
central space, the pressure at the centre being the same as at the end of
the cylinder into which the steam or air is admitted.
The manner in which this part of the said Invention operates is as
follows: As represented in Figure 6, the piston has completed its
stroke in one direction, and in so doing it shifted the valve to the
position indicated, whereby the live steam or air is admitted from the
chamber B through the port o' into the cylinder behind the piston to
force it back, the wing that the same time passing the mouth of the
port c¹, thus shutting off communication between this port and the live
steam or air in the chamber B', and permitting the steam at the front
end of the piston to pass through the port c¹ into the space between the
wings and , and thence out through the hole D¹, as indicated by the
arrows.
When the piston has moved a certain distance it shifts the valve,.
thereby reversing the flow of the steam through the ports, and thus the
operation is made continuous.
The distance that the piston moves before operating the valve depends
upon the width of the groove a¹, or in other words upon the amount of
lost motion between the piston and the valve lever 6', which by means
of any adjustable device attached to the end of the lever may be varied
at will if such variation be desired. In pistons of this kind, which are
made unusually long in order to afford a large bearing surface to prevent
rapid wear it is apparent that if the piston were made solid it would be
very heavy. This difficulty is obviated by boring a series of holes longi-

page_text: tudinally into it from the ends and then filling these holes with wooden
plugs n², as shewn in the right end of Figure 7 and in Figure 8, or the
piston may be made with a single cavity, which after being filled with
wood may have a screw cap J' fitted therein, as shewn in Figure 7. By
filling these holes with wood the accumulation of fluid therein is pre-
vented which would otherwise occur by condensation were the piston
simply left hollow. In this way is made a piston which has a long
bearing and yet is not excessively heavy.
In Figures 9 and 10 is represented a valve of slightly different con-
struction to that above described. C* indicates the cylinder; P³, the
piston; and V the valve of an engine such as is used for rock drills.
The valve in this case is an oscillating one, and is operated by direct
contact of its arm or lever with the piston, as shewn in Figure 9. This
arm or lever is composed of two spring bars e, e, both being rigidly
connected to the valve V², and of suitable length to reach down into the
annular recess at the centre of the piston. The free or lower ends of
these spring arms e² are curved or rounded so as to present a fair bearing
against the shoulder of the piston in whatever position the valve may be,
and so as to produce a rolling rather than a sliding motion when the
parts come in contact. The extreme ends of these spring arms are
curved inward, and are directly opposite each other, but a little distance
apart, as represented in Figure 10, by which it will be seen that when
the piston first comes in contact with one of the arms it may yield
slightly, at the same time exerting a force tending to start the valve, and
when it has moved a distance equal to the space between the ends of the.
two arms it will come in contact with the other arm, when the force will
be transmitted through both together. It will thus be seen that the
valve is started and stopped with much less of the jarring or concussion
than it would have if operated by a rigid instead of a yielding or spring
arm, while the wear of the parts is materially diminished and their
action made more smooth and easy.
In Figures 11 and 12 A³ represents the rear head of the cylinder, and
B³ a plate connected therewith by posts f³; D³ is the feed screw by which
the drill is fed. The rear end or smooth portion of this screw passes
through the plate B³, and has attached to it outside of this plate a gear
wheel c³, which engages with an intermediate gear wheel 6³, revolving on
a stud projecting from the plate B³. This latter gear wheel 68 engages
with another gear wheel a³, which is provided with an elongated

page_text: bearing, that revolves in a suitable bearing * in the plate B³, the said
wheel being provided with a flange m³ to keep it in place.
Through the gear wheel a³ is formed a square opening, in which slides
a correspondingly shaped bar G³, provided at its outer end with a
handle H³, by which it can be rotated by hand as desired; M³ is a rod
which extends through the rear head of the cylinder, and is kept from
any longitudinal motion by a flange p³ and a collar 9. The end of the
rod M³ within the cylinder enters an opening made to receive it in the
piston (not shewn) which slides over this rod, and is at all times in con-
Otact therewith, the piston being kept from turning independently of the
rod M³ by a spline and feather, and thus as the rod M³ is rotated in a
manner to be presently explained the piston and drill are turned as
desired. The rear end of the rod M³ extends up close to the end of the
gear wheel a³, and has a square opening of corresponding shape, and
3 directly in line with that passing through the gear wheel, and thus as
the rod G is moved forward through the gear wheel a³ it enters the
opening in the end of the rod M³, which is thereby coupled with the gear
wheel, and thus through the connections described as the gear wheel a³
is revolved; by turning the handle H³ the feed screw and the piston are
rotated at the same time, the relative proportion of the gear wheel being
such as to give the desired amount of feed as the drill is turned.
When it is desired to feed forward the drill or withdraw it from the
hole without rotating the piston, the bar G³ is moved back to withdraw
its end from the opening in the rod M³, when the feed screw can be
turned either way, forward or backward, independently of the piston by
means of the handle H³.
Near the rear end of the feed screw D³, between its smooth and
threaded portions, is a collar or enlargement &, which fits into the open
end of a hollow washer ³ surrounding the smooth portion of the screw,
between its rear support B' and the collar &. Within the hollow washer
us is placed an elastic washer or spring &³ of leather, rubber, or other
suitable substance, against which the collar is drawn firmly by a nut.
to outside the gear wheel c³, and by thus interposing an elastic cushion.
or spring between the collar and the support B³, the collar is kept
from being battered and destroyed by the concussion to which it would
otherwise bo subjected by the movement of the piston,

page_text: central space around the piston is kept filled with live steam or air, as
above set forth.
Also, the piston P¹ having a cavity or cavities formed therein and
filled with wooden plugs n¹, substantially as shown and described.
Also, an oscillating valve provided with an elastic arm constructed to
operate, as above described.
Also, the oscillating valve V provided with the spring arm or lever,
composed of the two arms e³, e², constructed to operate as above set
forth, whereby the two shall come into operation successively as
described.
Also, the combination of a semi-rotating valve provided with an
elastic stem, and a piston having a recess for the reception of the end of
the valve stem, as shown and described.
Also, connecting the rod M³ by which the piston is rotated with the
feed screw D³ by gear wheels, substantially as described.
Also, the coupling device G³, ³, in combination with the gear wheels
as, bs, cs, the feed screw D³, and the rod M³ by which the piston is
rotated, as above set forth.
Also, the elastic buffers B+ placed outside the cylinder in combination
with the collar or enlargement A' on the piston, as above set forth and
for the purpose specified.
Also, an elastic washer or spring interposed between a collar or
enlargement (³ on the feed screw and its support B³, as herein set forth
and for the purpose described.
In witness whereof, I, the said George Haseltine, have hereunto set
my hand and seal, this Ninth day of February, in the year
of our Lord One thousand eight hundred and seventy-five.
GEORGE HASELTINE. (L.S.)
Witness,
HY. JA'. NOONE.