Improvements in Percussion Drills and other Percussion Tools Worked by a Rapidly Rotating Motor.
Year: 1893

page_text: Date of Application, 14th Dec., 1893
Complete Specification Left, 31st Aug., 1894-Accepted, 6th Oct., 1894
[Communicated from abroad by Messrs. SIEMENS & HALSKE, of Berlin, in
the German Empire, Electrical Engineers.]
Improvements in Percussion Drills and other Percussion Tools
Worked by a Rapidly Rotating Motor.
We, SIEMENS BROTHERS & Co. LIMITED, of 12 Queen Anne's Gate,
Westminster, in the County of Middlesex, Electrical Engineers, do hereby declare
the nature of this invention to be as follows:-
For driving transportable percussion tools such as percussion drills operating
with reciprocating rectilinear motion, there have heretofore only been employed
with advantage motor engines which directly produce a reciprocating rectilinear
motion, such as compressed air engines and electro magnetic solenoid motors.
The application of rotative motors, such as ordinary electro motors, cannot be
effected with advantage in the ordinary way, on the following grounds.
The percussion work practically excludes, even with the use of suitable elastic
transmission, such for example as that described in the Specification to Patent
No. 14794 of 1891 the use of toothed wheel transmission. The motor must
therefore be made to act directly upon the crank or other similar mechanism for
producing the reciprocating motion of the tool, and it must therefore make as many
revolutions as the tool makes operation strokes. The motors however, and in
particular the electro motors give a very low efficiency with a slow speed such as
is determined by the speed at which the percussion tool operates usefully, and they
have consequently to be made of considerable weight, and such weight, added to
that of the percussion tool renders the transport of the entire apparatus very
difficult if not prohibitive in particular in mines.
The use of light motors running at a high speed would obviate this difficulty,
but it is only possible if the considerable percussion action of the working tool be
prevented from being transmitted to the gearing or the transmission devices
whereby the motion of the motor is transmitted at a reduced rate of speed to the
tool. The transport will be still farther facilitated if the motor is entirely separated
from the percussion apparatus, and the transmission of the driving power is effected
by a suitable transmitting device that can be readily disconnected from the one or
other part, and which is sufficiently flexible to allow of variations in the relative
positions of the two parts.
But even this arrangement cannot be employed if it is not protected against the
action of violent concussions.
The present invention relates to a construction of such apparatus whereby it is
rendered possible to employ a rapidly working motor and to arrange the same
separate from the percussion tool apparatus.
For this purpose there is provided on the driving shaft of the percussion
apparatus a fly wheel which is driven by a quick speed motor through the medium
of a flexible or jointed transmission shaft and suitable speed reducing gearing the
energy thus stored in the flywheel being expended in imparting the percussion
motion to the tool. The momentary reduction of the speed of the fly wheel by the
transmission of this energy is so slight, and the recovery thereof during the
remainder of the revolution by the transmission of energy from the motor is so
gradual that no material reaction of the percussion upon the driving gear and
motor is perceptible. The transmission shaft which effects the transmission of the
energy is so arranged as to be readily connected to and disconnected from the motor,
TU 71

page_text: and it is in addition of such a nature as to allow of its assuming a curved form or
other shortened form when the work of percussion drilling is first started and to
straighten out or extend so as to follow the forward motion of the percussion tool
as the work proceeds; it also allows of the motor being placed in such varying
positions relatively to the working apparatus as the exigencies of the locality may
require. Specially well adapted for this purpose is any known construction of
flexible shaft but other forms of shafting such as telescopic shafts with universal
joints may be employed.
In the arrangement employed by preference, the motor shaft carries a spur pinion
gearing with a spur wheel on the end of the transmission shaft, proportioned so as
to impart the requisite reduced speed to the latter; the other end of the trans-
mission shaft is connected by a readily detachable coupling or clutch to the short
shaft of a bevil wheel, gearing with another bevil wheel on the driving shaft of the
percussion tool.
This shaft is carried in a tubular stem forming part of the framing of the
apparatus, and upon this stem is rotatably mounted a box frame carrying the shaft
of the bevil wheel to which the transmission shaft is coupled, so that when setting
up the machine the said box frame can be turned upon the tubular stem until the
end of the transmission shaft is brought into the position which will give it the
least possible amount of bend, after which the box is secured on the stem by a
setting screw.
The flywheel may for facility of transport be secured in a detachable manner,
such as by a jam nut and dowel pins, on the boss of the second bevil wheel.
The motion of the driving shaft of the percussion tool is imparted to the latter
by a crank excentric or other known device in any suitable manner such as that
described in the said Specification No. 14794 of 1891.
The advance of the per-
cussion tool as the work proceeds may be effected either by hand or by any known
automatic mechanism:
Dated this 14th day of December 1893.
ABEL & IMRAY,
Agents for the Applicants.
עם VVI
DI MUITICATION.
Improvements in Percussion Drills and other Percussion Tools
Worked by a Rapidly Rotating Motor.
We, SIEMENS BROTHERS & Co., LIMITED, of 12- Queen Anne's Gate,
Westminster, in the County of Middlesex, Electrical Engineers, 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:-
For driving transportable percussion tools such as percussion drills operating
with reciprocating rectilinear motion, there have heretofore only been employed
with advantage motor engines which directly produce a reciprocating rectilinear
motion, such as compressed air engines and electro magnetic solenoid motors.
The application of rotative motors, such as ordinary electro motors, cannot be
effected with advantage in the ordinary way, on the following grounds
-
The percussion work practically excludes, even with the use of suitable elastic
transmission, such for example as that described in the Specification to Patent
No. 14794 of 1891, the use of toothed wheel transmission. The motor must
therefore be made to act directly upon the crank or other similar mechanism for
producing the reciprocating motion of the tool, and it must therefore make as
many revolutions as the tool makes operation strokes. The motors however, and
in particular the electro motors give a very low efficiency with a slow speed such as
is determined by the speed at which the percussion tool operates usefully, and they

page_text: have consequently to be made of considerable weight, and such weight, added to
hat of the percusssion tool renders the transport of the entire apparatus very
lifficult if not prohibitive in particular in mines.
The use of light motors running at a high speed would obviate this difficulty,
out it is only possible if the considerable percussion action of the working tool be
prevented from being transmitted to the gearing or the transmission devices
whereby the motion of the motor is transmitted at a reduced rate of speed to the
tool. The transport will be still farther facilitated if the motor is entirely
separated from the percussion apparatus, and the transmission of the driving
power is effected by a suitable transmitting device that can be readily disconnected
from the one or other part, and which is sufficiently flexible to allow of variations
n the relative positions of the two parts.
But even this arrangement cannot be employed if it is not protected against the
action of violent concussions.
The present invention relates to a construction of such apparatus whereby it is
rendered possible to employ a rapidly working motor and to arrange the same
separate from the percussion tool apparatus.
For this purpose there is provided on the driving shaft of the percussion
apparatus a fly wheel which is driven by a quick speed motor through the medium
of a flexible or jointed transmission shaft and suitable speed reducing gearing the
energy thus stored in the fly wheel being expended in imparting the percussion
motion to the tool. The momentary reduction of the speed of the fly wheel by
the transmission of this energy is so slight, and the recovery thereof during the
remainder of the revolution by the transmission of energy from the motor is so
gradual that no material reaction of the percussion upon the driving gear and motor
is perceptible. The transmission shaft which effects the transmission of the energy
is so arranged as to be readily connected to and disconnected from the motor, and
it is in addition of such a nature as to allow of its assuming a curved form or other
shortened form when the work of percussion drilling is first started and to
straighten out or extend so as to follow the forward motion of the percussion tool
as the work proceeds; it also allows of the motor being placed in such varying
positions relatively to the working apparatus as the exigencies of the locality may
require. Specially well adapted for this purpose is any known construction of
flexible shaft but other forms of shafting such as telescopic shafts with universal
joints may be employed.
The accompanying drawing shews a construction of percussion drill driven by
an electro motor separate from the drill according to the above described
invention.
Figure 1 shews a side view and Figure 2 a plan partly in section.
The motion of the electromotor M is transmitted at a reduced speed to a flexible
shaft W through the toothed pinion R' and wheel R*.
The shaft W is connected at its other end through a clutch V to the shaft of a
bevil wheel R gearing with another bevil wheel R on the boss of which is fixed
a fly wheel S, and the shaft K of which imparts reciprocating motion by means of
a crank and slot to the percussive drill in any suitable known manner, such as that
described in the Specification to the before mentioned Patent. The advance of
the drill may be effected either by hand as shewn or automatically as described in
the Specification to our application No. 24084 of 1893.
The flexible shaft W can be readily detached from the drill by means of the
clutch V.
As the drill requires to be capable of being mounted higher or lower and at
different angles, an arrangement is provided whereby the shaft W can be connected
without being bent too sharply.
part
For this purpose the wheel R³ is carried by a casing G that can be turned round
on the tubular T of the framing which carries concentrically the driving
shaft K of the drill, so that the casing G can be turned round to suit the best
position for the shaft W and be then secured by a setting screw D.

page_text: The weight of the fly wheel S need only be moderate; for convenience of
transport it may be made readily detachable from the bevil wheel R*, for which
purpose it is fitted loose on to the boss of the wheel, with a dowel pin d entering
a hole in the latter, and be secured by means of a screw nuts screwed on to the
threaded end of the boss of Rt.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what
we claim is :-
-
1. Driving percussive drills and other machines working with percussive tools
by means of a motor engine separate from the machine, to which the motion of the
motor is communicated by means of a flexible or articulated shaft operating in
combination with a fly wheel on the driving shaft of the machine, substantially as
described.
2. For imparting motion to a percussive tool from a separate motor, the com-
bination with a bevil wheel R* mounted on the driving shaft K, of a bevil wheel R³
connected by a clutch with a flexible or articulated shaft W, and carried by
casing G rotatable on a boss T of the framing that carries the driving shaft K, so
that the casing G and wheel R³ can be adjusted to suit the best position of the
shaft W, substantially as described.
Doted this 31at dex of August 1804
ABEL & IMRAY,
Agents for the Applicants.