Improvements in Means or Apparatus for Actuating Hammering, Caulking, Rock-boring, or like Percussive Machinery by the Aid of Electricity.
Year: 1891

page_text: Date of Application, 29th Apr., 1891
Complete Specification Left, 29th Jan., 1892-Accepted, 5th Mar., 1892
PROVISIONAL SPECIFICATION.
Improvements in Means or Apparatus for Actuating Hammering,
Caulking, Rock-boring, or like Percussive Machinery by the Aid
of Electricity.
We REGINALD BOLTON of 110 Leadenhall Street in the City of London, Civil
Engineer, and WILLIAM CHARLES MOUNTAIN of Close Works, Newcastle-on-
Tyne in the County of Northumberland, Electrical Engineer do hereby declare
the nature of this invention to be as follows:-
Our invention relates to improvements in means or apparatus for actuating
hammering, caulking, rock-boring, or like percussive machinery by the aid of
electricity wherein a hammer, tool, jumper, drill-bit or other implement attached
to a piston is thereby caused to reciprocate and to strike a blow on the work
or rock.
According to our improvements we obtain the said reciprocation by the tractive
drawing power of electro-magnets or solenoids acting upon a soft iron ring, bar, or
part attached to the reciprocating parts by an elastic or flexible connection,
whereby the shock of the blow or of the over-running of the reciprocating parts is
taken from the electrical working parts, and the resulting stroke is variable in
extent and the blow thereof is of an elastic or springy nature.
This is a most important feature in rock perforation and by its means we are
enabled to attain an electrical reciprocation of a fixed distance, with a variable
reciprocation of the drill rod.
In one arrangement of apparatus embodying this invention and designed for use
as an electrical percussive rock drill we provide a drill piston and rod which may
be (say) of a similar form to that in common use on drills propelled by a com-
pressible fluid. This piston is enclosed in a small cylinder with a sliding fit, and
may be provided with piston rings, grooves or equivalent packing.
Air is admitted into either end of the interior by small holes circumferentially
drilled at convenient points such as near the centre and so located that a supply of
air at a suitable part of each stroke is admissible.
It will be evident that the air enclosed at each end of the cylinder acts as a
buffer or cushion to the drill or hammer piston at the end of each stroke.
At the same time a spiral or other spring rubber cushion or buffer may be
equally employed for the purpose.
The reciprocating motion from the electrical apparatus is imparted to the
cylinder; the drill piston receiving its motion from the elastic or other medium
provided in either end thereof, and is not directly attached to the electric parts nor
dependent for the exact length of its stroke thereupon.
In fact the drill tool strikes against the rock by an elastic medium behind it and
should its blow not be received by the rock its momentum is taken up by the
elastic medium in front of it which it compresses.
We provide a further cushion or relief upon which the motion of the reciprocating
cylinder itself is arrested by means of a recess at either end of the casing into
which the end of the reciprocating cylinder forces itself.
Into this recess we introduce air, a spring or rubber cushion or like device.
The electrical apparatus consists of a ring or bar of soft iron attached rigidly to
the reciprocating cylinder by screwing or bolting thereto; the latter being pre-
ferably made of gun metal or other material not affected by magnetic or electric
influence.
The reciprocation is effected by alternate pulsations of electric energy produced
either by an alternating dynamo or by switching a direct current passing through
coils wound on iron cores in a well known manner, suitably arranged and attached

page_text: to the interior of the end covers of the apparatus or otherwise in such a manner
that their attractive force alternately acts in opposite directions upon the soft iron
ring which is attached to the reciprocating cylinder.
The whole apparatus may be enclosed in a strong circular case or cover of
suitable form, and the same may contain the usual apparatus for the rotation of the
drill piston, by means of a rifle-bar, nut, ratchet-wheel and pawls or equivalent.
The feed may be attained by an abutment attached to the entire apparatus being
connected by a nut to a fixed screw in a well known or other convenient manner.
By mounting the apparatus as described upon a suitable framing the same will
form an electrical hammering tool, or in a compact and portable form of suitable
dimensions it becomes suitable for use in caulking the seams of boilers and tanks.
In the adaptation of the apparatus to the requirements of electrical hammers
wherein a longer stroke may be required and in which the blow may be very
severe we use the following arrangement:
The reciprocation of the cylinder is effected by a lever, preferably of steel, which
may be formed of laminated springs in a well known manner attached by links to
the cylinder and the fulcrum of which is made fast to any convenient point in the
framing.
This lever is provided with the soft iron bar or ring previously described and is
thereby reciprocated by the action of the magnets arranged conveniently on
opposite sides thereof.
This arrangement enables a short play of the magnetic parts to be translated at
the end of the lever into a lengthened motion of the percussive parts.
It is evident that the magnets described may by a simple arrangement be made
into solenoids and, by winding them on a hollow sleeve or socket and providing the
reciprocating parts with a pole or plunger of corresponding diameter entering and
fitting therein, the said plunger or pole may be made to do duty as the secondary
cushioning apparatus, the appropriate holes for admission of air being drilled in the
sleeve or socket.
It is evident that by an inverse arrangement the hammer head or drill-bar may
be attached directly to the cylinder, and the same may be operated by the recipro-
cation of the interior piston, by attaching thereto a piston rod extending out at the
rear end, or even by trunnions extending through slots in the side of the cylinder
and operated by the reciprocating electrical parts.
We are aware that the reciprocation of a percussive rock drill by electrical sole-
noidal and magnetic reversal has been before described and used with limited
success but we are not aware that such electrical reciprocation has ever been
accompanied by connection of the parts by an elastic or fluid connection.
By these means we are enabled to attain in a hammer, caulking tool, rock-drill,
or other like percussive machine, the following advantages:
:-
The use of electro magnets producing a reciprocating motion and imparting the
same to the tool or implement by an elastic medium.
Also an elastic and variable stroke of a tool or implement produced by electrical
reciprocations from electro magnets.
In an electrical rock drill or hammer the combination of electro magnets recipro-
cating a cylinder and operating the drill bar or hammer head by fluid or elastic
connection.
The arrangement of an electrically reciprocated drill cylinder, a free drill bar
elastically impelled thereby, and an elastic buffer or cushion to receive the recoil or
over running of such drill bar and cylinder.
The arrangement of electro-magnets axially disposed around a reciprocating
drill cylinder and impelling the same by alternate electro-attractions on a soft iron
ring, bar or part connected to such cylinder.

page_text: COMPLETE SPECIFICATION.
Improvements in Means or Apparatus for Actuating Hammering,
Caulking, Rock-boring, or like Percussive Machinery by the Ald
of Electricity.
•
We REGINALD BOLTON of 110 Leadenhall Street in the City of London Civil
Engineer, and WILLIAM CHARLES MOUNTAIN of Close Works, Newcastle-on-
Tyne in the County of Northumberland, Electrical Engineer 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 :—
Our invention relates to improvements in means or apparatus for actuating
hammering, caulking, rock-boring, or like percussive machinery, by the aid of
electricity, wherein a hammer, tool, jumper, drill-bit or other implement attached
to a piston is thereby caused to reciprocate and to strike a blow on the work
or rock.
G
According to our improvements we obtain the said reciprocation by the tractive
drawing power of electro-magnets or solenoids acting upon a soft iron ring, bar, or
part attached to the reciprocating parts by an elastic or flexible connection,
whereby the shock of the blow or of the over running of the reciprocating parts is
taken from the electrical working parts, and the resulting stroke is variable in
extent and the blow thereof is of an elastic or springy nature.
This is an important feature in rock perforation and by its means we are enabled
to obtain an electrical reciprocation of a fixed distance, with a variable recipro-
cation of the drill rod.
In one arrangement of apparatus embodying this invention and designed for use
as an electrical percussive rock drill we provide a drill piston and rod which may
be (say) of a similar form to that in common use on drills propelled by a com-
pressible fluid.
This piston is enclosed in a small cylinder with a sliding fit and may if desired
be provided with piston rings, grooves or equivalent packing but we have not
usually found such to be requisite.
Air is admitted into and emitted from either end of the interior by means of
holes of restricted area provided at convenient points such as near the centre and
so located that passage of air during a determined part of each stroke is permitted,
whilst such passage is arrested during the final portion thereof; thereby creating
a cushion of air.
It will be evident that this air enclosed at each end of the cylinder acts as a
buffer or cushion to gradually arrest the drill or hammer piston in one direction,
and as an expansive medium to restart in the opposite direction.
A spiral or other spring, rubber buffer or mechanical equivalent either in
substitution for or in addition to the air may be employed for these purposes, but
we find the employment of air simpler and more effective, there being no com-
pressible material liable to be destroyed by heat or over compression.
The reciprocating motion from the electrical apparatus is imparted to the
cylinder; the drill piston receiving its motion from the elastic or other medium
provided in either end thereof, and is not directly attached to the electric parts nor
dependent for the exact length of its stroke thereupon.
The impact of the drill tool against the rock is attained by the intervention of an
elastic medium behind it, and should its blow, not be received by the rock its
momentum is taken up by the elastic medium.
A further cushion or relief upon which the motion of the reciprocating cylinder
itself is arrested by means of recesses at either end of the casing may be provided.
into which recesses containing air, a spring or rubber cushion or like device, the
ends of the reciprocating cylinder are forced.
The electrical apparatus consists of a ring or bar of soft iron suitably attached to

page_text: the reciprocating cylinder or part; the latter being preferably made of gun metal
or other material less affected by magnetic or electric influence.
The reciprocation is effected by alternate pulsations of electric energy produced
either by an alternating dynamo or by switching a direct current passing through
coils wound on iron cores in a well known manner, suitably arranged and attached
to the interior of the end covers of the apparatus or otherwise in such a manner
that their attractive force alternately acts in opposite directions upon the soft iron
ring which is attached to the reciprocating cylinder or part.
The whole apparatus may be enclosed in a strong circular case or cover of
suitable form, and the same may contain the usual apparatus for the rotation of the
drill piston, by means of a rifle-bar, nut, ratchet-wheel and pawls or equivalent
arrangement.
The feed may be attained by an abutment attached to the entire apparatus,
connected by a nut to a fixed screw in a well known or other convenient manner.
By mounting the apparatus as described upon a suitable framing the same will
form an electrical hammering tool.
A compact and portable caulking tool for seams of boilers and tanks may be
attained.
For electrical hammers wherein a longer stroke may be required and in which
the blow may be very severe we find the following arrangement very useful.
The reciprocations of the cylinder are transmitted to the hammer by a lever,
which may be formed of laminated steel or other springs in a well known manner
attached by links to the cylinder and the fulcrum of which is made fast to any
convenient point in the framing.
This lever is attached to the soft iron bar or ring previously described with
which the cylinder is provided and is thereby reciprocated by the action of the
magnets arranged conveniently on opposite sides thereof. This arrangement
enables a short play of the magnetic parts to be translated at the end of the lever
into a lengthened motion of the percussive parts.
The magnets described may be made into solenoids by winding them on a hollow
sleeve or socket and by providing the reciprocating parts with a pole or plunger of
corresponding diameter entering and fitting therein, the said plunger or pole may be
made to do duty as the secondary cushioning apparatus, the appropriate holes for
admission of air being provided.
Figure 1 is a horizontal sectional view of an arrangement of the invention as an
electrical percussive rock drilling machine.
Figure 2 is a side elevation of another arrangement of the invention for operating
hammering mechanism.
Figure 3 is a sectional side view of a portion of the apparatus indicated in Fig. 1
with the exception that a modification is made in the addition of projections p, p², p³, p³
to the ring P.
One arrangement of apparatus, designed for use as an electrical percussive rock
drill, and embodying this invention is shown in Fig. 1, which is a horizontal section
through the centre of a rock drilling apparatus. In this A is a wooden casing of
circular form, closed at either end by metal covers B and C. The cover B is that
nearest the working or drilling end, and is provided with a gland or guide socket D
through which the drill piston-rod R slides.
The guide D is made in halves in a well known manner bolted together round
the rod R by bolts in bolt holes E E¹.
The rear cover C is provided with an extension C¹ in which is fitted the rotating
apparatus commonly in use in percussive rock drills, and consisting of the spirally
grooved rod Fenlarged at the rear end into a boss F¹ in which is fitted the pawl or
cam G pressed outwards by the spring G¹, and engaging in one direction with the
teeth in a ratchet ring H provided with internal teeth.
This ring H is held strongly, but not absolutely rigidly by the cover plates J, J₁
pressed together by a laminated spring K, secured to the cover C by bolt and
nuts L. This rotative arrangement is a well-known one, and the grooves in the

page_text: rod F engage in a corresponding nut M screwed into the drill rod, which is thus
partially rotated during its movement in one direction, but itself rotates the rod F,
during its movement in the reverse direction.
Upon each cover B and C are mounted several, and preferably 6 or 8 magnetic
coils of wire N wound in any usual or convenient manner as electro-magnets, each
upon a core or bar n secured to the covers B and C respectively by nuts O. These
coils are connected to the electro-leads in any well known or convenient manner,
and by a switch or other mechanism the coils are supplied with a current of
electricity, and when excited they cause a reciprocatory motion to the ring of soft
iron P which is free to vibrate between them first in one direction and then in the
other. This ring P is attached rigidly to the cylinder Q provided at its front end
with a screw cap Q' and a guide piece Q' made in halves, embracing the drill piston
rod R. The rod R is enlarged at its upper end and forms a piston in which is
secured the nut M.
A free space is left between the ends of the piston R and the ends of the
cylinder Q, and through the casing are bored small air-holes S, which admit a
supply of air to the interior of the cylinder Q. The air is compressed between the
cylinder and piston on any movement of one or other, and the piston is reciprocated
upon the vibration of the cylinder, by means of the compressed air. Inversely, at
the end of a stroke of the cylinder, the piston is arrested by the compression of the
air in front of it, which takes place as soon as the edge of the piston has passed the
air hole S.
A very similar arrangement of air cushioning is provided to arrest, elastically,
the movement of the cylinder Q which fits and slides in recesses bored out in the
covers B and C and which are like wise provided with air-holes T.
The apparatus described is carried in a slide U¹ upon a saddle U which saddle in
practice, as is commonly the practice, is attached by a bridle piece to a nut V
indicated in dotted lines. A screw W is fitted in the nut the end of which is
secured to a lug or abutment X preferably screwed to the cover C. By turning the
screw W with a handle or spanner the apparatus is fed towards its work or retired
therefrom.
The end of the piston rod R is enlarged at R' to receive a drill-bit or tool in a
well known manner.
An adaptation of the apparatus to the uses of an electrical hammer is shown in
Fig. 2, in which a is the casing, b and c the end covers, d the guides or gland, r the
piston rod, which rod r is for the sake of extraguiding surface extended out at the
rear end through a hole in the cover c.
The rotating arrangement is here dispensed with, and the rod r secured by hinged
connection e¹ to a laminated spring e, vibrating upon a pivot bearing f, situated upon
the main framing 9.
This main framing 9 provides a support for the electrical apparatus, and is pro-
vided also with an anvil face y', and a guide-arm g' in a bearing in which reciprocates
a hammer rod h armed with a tup or hammer head j. The rod h is attached to the
vibrating spring e, by hinged connection e³, and thus the vibration of the electric
piston rod is imparted to the hammer j.
By the admission of a current of greater or less intensity, at the will of the
operator by means of a switch combined with a rheostat or resistance coil of well-
known form, a blow varying in severity may be given.
Fig. 3 shows a modification of the vibrating mechanism described in Fig. 1.
In this case the magnetisable ring P is provided with a number of projections p³,
corresponding and fitting closely into holes p2 bored in the interior of the magnet
cores n. Small air holes m are provided communicating with the atmosphere, and
on over-running these, the confined air is compressed by the projections p', and the
motion of the ring P is softly and gradually arrested.
At the same time they form solenoids in connection with the coils surrounding
the cores, and at the commencement of a stroke are nearer to (and in fact are
within) the magnetic influence. This arrangement may be additional to the air

page_text: cushions already described, or be used to avoid those in the end covers B
and C.
We are aware that the reciprocation of a percussive rock drill by electrical
solenoidal and magnetic reversal has been before described and used with limited
success but we are not aware that such electrical reciprocation has ever been
attained by connection of the parts with the aid of an elastic or fluid connection.
By these means we are enabled to attain an electrically actuated hammer,
caulking tool, rock-drill, or other like percussive machine having an elastic cushion
or medium intervening with the advantages already indicated.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1: The arrangement or combination and use of electro magnets for producing a
reciprocating motion and imparting the same to the tool or implement with the
intervention of an elastic medium, substantially as and for the purposes hereinbefore
set forth.
2: The combination or arrangement of the parts of a percussive tool or
implement the strokes of which are produced by electrical reciprocation, so that
such strokes may be made elastic and variable by the intervention of an elastic
cushion or medium.
3: In a percussive drill or hammer the combination or arrangement and use of
an electrically reciprocated drill cylinder, a free drill bar elastically impelled
thereby, and an elastic buffer or cushion to take up the over-running and facilitate
the restarting of such drill bar and cylinder, substantially as set forth.
4: The combination or arrangement and use of electro magnets suitably
disposed around a reciprocating cylinder or part (which part they, by alternate
electro-attractions, operate) with the intervention of elastic media substantially as
set forth.
Dated the ZALO DAY OF TRADE.ry 105%.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicants.