Improvements in Striking or Hammering Mechanism.
Year: 1890

page_text: Date of Application, 18th Nov., 1890-Accepted, 25th Apr., 1891
COMPLETE SPECIFICATION.
Improvements in Striking or Hammering Mechanism.
I, THEODORE WELD STERLING, Gentleman, of Union League Club, Fifth
Avenue, in the City, County and State of New York, United States of America,
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 striking or hammering mechanism.
The object is, in an efficient manner, with proper conservation of mechanism, and
with selection of the proper period of time, to deliver blows with certainty.
The invention resides, essentially, in a striking or hammering device, and consists
of two hammers adapted to reciprocate in the direction of the blow to be given,
that is, in the direction of impact, and also to be reciprocated to and from the line
of impact bringing each hammer alternately into position, with time to strike its
object.
The invention may be embodied in various forms, the hammers to be reciprocated
to and from the line of direction of the blow in straight or curved path, and is
applicable to any use where blows are to be struck with certainty upon a given
point.
I illustrate the invention by a rectilinear reciprocation of the hammers to and
from the line of direction of the blow, and have elected to show its operation by
application to a percussion rock-drill of a device embodying it.
The special device for retaining the machine in position on its supporting
standard, and also constructions for effecting the partial rotation of the drill-tool and
other operations, are not designed to be covered in the present application, as they,
together with other details of construction, herein shown or described, and not
claimed, form the subject-matter of another application for Patent.
In the accompanying drawings,
Figure 1) is a view in perspective representing the striking device applied for
mere illustration of a mode of use, to rock-drilling mechanism, the top of the housing
of the striking-mechanism being removed to display the disposition of the operative
parts.
Figure 2) is a view, in vertical, longitudinal section, taken through the housing
of the striking mechanism and through the rock-drilling mechanism attached
thereto; leaving the hammers in elevation to display their shape, and leaving, also
in elevation, their springs, the stem seen of one, and its tube (more fully shown in
Figure 8) furthermore, a part-gear wheel for operating with mechanism (not
shown) to rotate the drill-tool; and, finally, a feed-screw for the drill-shaft, the
end of the drill-shaft and its casing being broken off beyond the sleeve.
Figure 3) is a view, in elevation, representing the rear of the striking
mechanism, the end of the housing being removed to display the parts.
Figure 4) is a view in perspective, representing the main driving shaft of the
striking-mechanism.
Figure 5) a view, in side elevation, the housing being removed, representing the
manner of drawing back the hammers against their springs.
Figure 6) is a view, in perspective, representing, in detail the means of moving.
the arm up and down to reciprocate the movable frame.
Figure 7) is a longitudinal section, vertically through the center of the box,
and transversely through the second shaft, leaving a gear-wheel beyond the box in
elevation.
Figure 8)-is a view, in vertical longitudinal section, taken through the fore part
of the stationary frame and the rear portion of the movable frame in the line of a

page_text: stem, each, for the upper and lower hammers, leaving the stems (broken away
towards the hammers) in elevation, as well as locking-levers or roller pawls, pawi-
springs, and a guide-bar, the casing being removed to display the parts.
Figure 9) is a view in elevation being a detail view of one of the lower locking
levers or roller-pawls.
Figure 10) is a vertical, longitudinal section of the same.
Figure 11) is a view, in perspective, representing the greater portion of the
stationary frame or the block, in a front recess or jaw of which the inovable frame,
carrying the hammers, slides.
Figure 12) is a view, in perspective, representing the greater portion of the
movable frame, in which the hammers are mounted.
It is desired to state, at the outset, that this invention is not limited, in its
application, to any specified form of object to be struck. For the purpose merely
of showing and explaining the principles of operation and use of the invention, its
application will be described in the form shown in the drawings as adapted to a
percussion rock-drill.
In the drawings,
A. A designate two hammers, having enlarged portions or heads a a² provided
with pins a a, and one or more reduced portions, each, or stems a³ aº, provided with
outward-facing, rounded notches a' as near their ends. The hammers are mounted
one above the other, but free to slide independently lengthwise, in a movable
frame B, consisting of two portions, an upright portion and a forward extension
portion, the extension having, at the side of each hammer, an inward-projecting,
longitudinal tongue or guide rib, which takes into a corresponding groove a, to
steady each hammer and hold it in proper position against individual displacement
or from the line of stroke, that is, in the present embodiment, against displacement
up or down, as the hammers, in this instance, are shown one above the other,
(though they may be side by side), the movable frame, having furthermore,
tubes fixed. in the front face of the main portion b, toward the hammers, and
which the ends of the stems of the hammers enter, free to slide therein. Upon the
stems of the haminers, are spiral springs C, C2, which abut at one end against the
front face of the movable frame, over the tubes, and, at the other, against the enlarge-
ments or heads of the hammers, these springs being the hammer-actuating springs.
The movable frame has grooves 6, in the sides of the upright portion, to permit
the frame to be guided in its movement, and has, furthermore, an arm 6, fixed in
it near its top and projecting backward beyond its rear face, by which arm the
frame can be moved, and recesses in the rear face, respectively, from above
downward and from below upward, each recess ending in a rounded opening into
which a tube is set, the recesses containing locking-levers or pawls 6102, to engage
the notches in the stems of the hammers, as shown in Figure 8, the levers carrying
rollers that enter the notches, in order that upon pressure of the levers outward,
the pawls may readily slip out of the engagement with the hammers and release
them to be actuated by the springs, and having their free ends projecting beyond
the plane of the rear face of the movable frame, to be struck and thrown out of
engagement with the notches. Behind the movable frame, is the stationary frame
or the block D, consisting of a main portion d, and upright strips or pieces d²,
confining the shafts at their bearings in the frame, the main portion d, having a
recess or jaw, d³, into which the movable frame is set with its grooves upon guide-
bars d', and with its arm in a cleft d. Projecting into the jaw from the top and
bottom of the block, are springs, de d', which, being opposite the recesses in the
movable frame, are in position to act against the locking levers as required, the
locking-levers being thrown out of engagement with their notches in the hammers
by striking against stops d.
Set into the block, at the rear, and at its lower part, is a main shaft E, having
spur gear wheels e e², and cranks or crank-bends e e¹, also a cam e', and, above the
main shaft E, with spur-gear wheels f, the gear-wheels e and fand es and f
respectively on the two shafts intermeshing, cranks f³ f, at the ends of the shaft

page_text: and a crank, between the gear wheels, or intermediate in the length of the shaft,
the two shafts being so geared that the cranks or crank-bends on the main-shaft and
the cranks on the ends of the second shaft, will be respectively in position relatively
diametrically opposite, and the cranks carrying links G G2, which turn on them at
one end (the rear end) and at the other end take over the pins on the hammer-
heads, the cranks on the main-shaft bearing the links which take over the pins on
the head of the lower hammer; and those on the second shaft carrying the links
which take over the pins on the head of the upper hammer. It will be obvious
that as the main-shaft revolves, the hammers will be drawn back one after the
other, by the links.
Upon the intermediate crank of the second shaft, is journaled a box f6, into
which an arm 7 passes, through the cleft, the box sliding slightly but freely on
the arm.
It will be obvious that as the second shaft is turned and its intermediate crank or
crank-bend revolves, with its box, the arm will be moved up and down, carrying
with it the movable frame, which is in this matter moved up and down, whereby
the hammers by it carried, will be reciprocated and there will be a period of rest at
the end of each movement up and down, before the opposite movement begins, it
being clear that the period of rest may be made greater or less by well known
means, for example, greater by having the box larger in vertical diameter than the
end of the arm.
As already described, the stems of the hammers are provided, near their ends, with
notches, and the movable frame, with pawls. Now the intermediate crank on the
second shaft is so set that when the upper hammer is drawn back, with its spring
or springs compressed to the fullest extent, the movable frame will be at its
uppermost limit of motion, bringing the upper pawl into the notch or notches of
the upper hammer, retaining it until, upon movement of the frame in its contrary
direction, about centrally, the pawl or pawls will strike against the stop on the
stationary frame, and, releasing the stem or stems, the upper hammer will be shot
forward by the actuating spring or springs, to deliver its blow; while when the
lower hammer is drawn back with its spring or springs compressed to its fullest
extent, the movable frame will be at lowermost limit of motion, bringing the lower
pawl or pawls against the lower pawl-spring or springs and forcing the
pawl into the notch or notches of the lower hammer, retaining it until,
upon movement of the frame in the contrary direction about centrally, the
pawl or pawls will strike against the projection on the stationary frame,
and releasing the stem or stems, the lower hammer will be shot forward
by the actuating spring or springs to deliver its blow. Otherwise stated,
the shafts are so geared with each other that they act upon the respective actuating
springs through their cranks and connecting links alternately, and the box
mounted upon the shaft is so arranged with relation to the other moving parts of
the machine, and its operation is so timed, that each hammer respectively is at the
outward limit of the motion of the frame farthest removed from the drill-tool or
part holding the drill-tool when its spring is compressed and the notch in the
hammer is entered by its pawl, and it is carried to a point opposite the drill tool
when its locking-lever is moved from the hammer releasing it.
It may be here noted that delivery of a blow takes place at a time when the
reciprocatingly-moving frame having reached its extreme position in one direction
or the other, is about to retrace its course, that is, at a moment when it is
deprived of motion, having no motion either in one direction or the other. The
delivery of the blow being practically instantaneous under the quick action of the
springs, it may be said that the movement of the hammer at that time is all, in one
direction, that is, in the direction of the object to be struck.
The advantage of reciprocation of the operative part to and from the line of
direction of its action is, first, that, by reciprocation,, more than one hammer can be
employed, instead of having to use a single hammer, thus dividing the labor and
consequent wear and tear; and, secondly, that, by reciprocation, or alternation, as

page_text: distinguished from constant motion onward, or succession, a period of rest is afforded,
at the end of each movement, namely just before return, and just then the striking
can be performed.
The drill-shaft of the rock-drilling mechanism to which the striking device is
here applied, is marked H, and is in a tube which extends from the housing of the
striking mechanism and is supported upon a standard F by a collar i and sleeve h
which permits the drill shaft and consequently the drill to be swung up or down, to
be turned or shifted around, and also to be moved longitudinally or to slide, there
being a rock-shaft K outside of the housing of the striking mechanism to cause
rotation of the drill-shaft, and, thereby the drill, the rock-shaft having an arm k, at
one end, projecting laterally into the housing and toothed at its end (not shown) to
push the gear (not shown) at the drill-shaft; and having a lateral extension k² at
its, other end, taken under by the cam on the main-shaft of the striking
mechanism, there being at the upper end of the drill-tool, at its upper bearing,
free, part-gearing spur-wheel by which (with intermediate or ratchet-feed, not
shown), a ratchet pawl projecting inward from the collar and a ratchet-wheel being
fixed on the end of the drill-shaft p-the drill is rotated, the drill to be advanced
or drawn back in the standard, by having fixed to the sleeve h, a screw-threaded
tube L, free to slide in another tube M, in the housing of the striking mechanism,
and entered by a screw N, free to turn in the housing, but fixed against longitudinal
motion.
AL
It will be obvious that the screw-device may be employed for causing the
striking-device to advance or recede by itself.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare what 1
claim is :-
1.) In a striking device, in combination, a pair of independently reciprocating
hammers, and mechanism for reciprocating simultaneously both hammers in a line
crossing that of impact, substantially as described.
2.) A striking device, consisting of two hammers in combination with mechanism
operating to reciprocate each in the required direction of impact, and with
mechanism operating to reciprocate them to and from the line of direction
of impact, alternately, substantially as described.
3.) A striking device, consisting of two hammers in combination with actuating
springs, and mechanism for drawing back the hammers to compress the springs and
to reciprocate each hammer in the required direction of impact, and mechanism
operating to reciprocate them to and from the line of direction of impact alternately,
substantially as described.
4.) A striking device, consisting of two hammers, and a reciprocatingly movable
frame in which the hammers are mounted, in combination with mechanism operating
to reciprocate each hammer in the required direction of impact, and with
mechanism operating to reciprocate the frame in a direction crossing the line of
direction of impact, substantially as described.
5.) A striking device, consisting of two hammers in combination with actuating
springs and mechanism for drawing back the hammers and for compressing the
spring, to reciprocate each hammer in the required direction of impact, hammer
locking and releasing devices, and mechanism operating to reciprocate the hammers
to and from the line of direction of impact, alternately, substantially as described.
Dated this 18th day of November 1890.
THEODORE WELD STERLING.
Per G. G. M. Hardingham,
191, Fleet Street, London, E.C., Associate Agent.
THEODORE WELD STERLING.
Per G. G. M. Hardingham,
191, Fleet Street, London, E.C., Associate Agent.