Improvements in Boring Apparatus for Deep Borings.
Year: 1893

page_text: Date of Application, 4th Aug., 1893-Accepted, 16th Sept., 1893
COMPLETE SPECIFICATION.
Improvements in Boring Apparatus for Deep Borings.
I, ANTON RAKY, of Dürrenbach, Elsass, in the German Empire, 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 :-
This invention relates more particularly to that class of boring apparatus for deep
borings in which rigid boring rods are employed actuated from a crank and has for
its objects, apart from the variable speed transmitable by the said crank, to improve
the action of the boring tool and prevent the rods breaking. The first object is
attained by slackening the belt (chain or rope) which drives the crank after the
rods have commenced descending and whereby the descent of the rods and the
chisel remains unchecked. The breakages are obviated by mounting the beam
elastically.
And in order that my invention may be more fully understood I have caused to
he appended hereunto one sheet of drawings marked with letters of reference
indicating like parts in the various figures.
Fig. 1 is a front view and Fig. 2 a plan of the apparatus constructed in accordance
with my invention.
Figs. 3-5 are various modifications of the driving gear of the same.
m is the heavy rod which has attached the chisel n.
The heavy rod m, by means of the rods o, is connected with the beam B, which
latter is connected through the rod p with the crank lever u. The latter is driven
by the motor pulley 7, by means of the belt on the pulley T. The latter revolves
in the direction of the arrow.
In contact with the part of the belt which does not drive is arranged the
tightening pulley P, which is carried by a lever E having its fulcrum at f and
carrying a weight g.
On the pulley T is employed adjustably the segment h which comes into contact
with the corresponding segment d arranged in connection with the tightening
pulley P, when the rods have commenced their descent and thereby depressing the
pulley P and thus slackening the belt b.
The action of the device described is as follows:-
The boring tool lifted at a gradually increasing speed, reaches its highest point
at a slowly decreasing speed and drops afterwards at a constantly increasing speed
until the blow takes place.
As soon as the segment has pressed the tightening pulley P down the belt b is
slackened, so that it slips on the pulley a. In consequence of this the rod m, on
account of its weight and force, pulls the rods o and being unchecked in its descent
turns the crank and pulley T quicker, which latter is free to revolve at an increased
speed owing to the belt & riding loose. The boring chisel arriving at its working
position operates at its highest speed and is therefore more effective, than that
actuated by the ordinary crank, as by the same the final speed on the descent is nil.
The advantage thus attained compared with the crank where the whole of the stroke
is not utilized, consists in utilizing the power more rationally.
Fig. 3 shows how the tightening pulley may be moved back selfactingly by the
belt. As described when the boring tool drops, an increased speed of the pulley T
is attained so that the lower part of the belt becomes operative. This causes the
lower part of the belt b to draw the tightening pulley P downwards and the belt to
slip at times and release the pulley T, as is the case in the previously described
arrangement.
Fig. 4 shows a pulley P which is mounted eccentrically and receives rotary motion

page_text: from the crank shaft, through the chain k in lieu of the tightening pulley operated
by a weight, the effect being the same in both cases.
The modification shown in Fig. 4 represents the driving belt substituted by a
chain, the wheels are considerably smaller than in the former arrangement so that
the slipping is unnecessary and the use of a chain rendered possible. The tightening
pulley in this case is also formed as a chain wheel and otherwise mounted
eccentrically.
To prevent breakage the following device is employed
The boring rods as connected to the beam B as described and can be adjusted as
usually by means of a screw S, .e. according to the progress of the boring the set
of the chisel may be altered.
The drop of the chisel being unchecked great danger of breakage exists if the
chisel is not set very accurately. If the chisel is set too deep it will rebound and
cause the lowest rod to break, whilst on the other hand when set too high it exerts
to great a pull on the beam, owing to the force of the descending boring rods not
being checked and thus the beam or crank caused to break.
These dangerous defects are obviated by mounting the beam B clastically. As
will be seen from Fig. 1, the pivot of the beam is mounted in a bearing which
rests on springs s and will thus give, the chisel must however be set so that it will
not touch the bottom of the boring in its lowest position when at rest.
The action is thus as follows:-
By an unchecked descent of the heavy rod, owing to the weight thereof, the chisel
is thrown further down although it does not quite touch the bottom of the boring
when at rest, to which movement the beam yields owing to being mounted elastically,
the boring rods are thus only subjected to pull, so that danger of breakage is
obviated. The beam and crank themselves are built strong enough not to break.
The pressure in the boring is equalized by the extraordinary heavy boring rod.
It will be evident that in this manner the beneficial effect is greatly increased,
the prevention of shocks being well known to ensure said effect.
Having now particularly described and ascertained the nature of this inveu-
tion and in what manner the saine is to be performed, I declare that what I
claim, is-
1st. In a boring apparatus for deep borings in which the boring rods are rigid
and actuated from a crank, a crank motion in which the belt (chain or rope) which
drives the crank a is slackened after the boring rods have commenced to descend,
which effects an unchecked drop of the heavy rod m and chisel n, substantially as
set forth, with reference to Figs. 1-5.
k
2nd. In a boring apparatus for deep borings in which the boring rods are rigid
and actuated from a crank, a crank motion, in which the belt (chain or rope) which
drives the crank a, is under the influence of a tighting pulley P which, after the
commencement of the descent of the boring rods slackens the belt b and thereby
effects an unchecked drop of the heavy rod m and chisel n, substantially as
set forth.
3rd. In a boring apparatus for deep borings in which the boring rods are rigid
and actuated from a crank, a crank motion in which the belt (chain or rope) which
drives the crank is under the influence of a tightening pulley P, which is depressed
after the commencement of the boring rods by the segment hon and rotating with
the pulley T, whereby the belt b is slackened and thus causes the drop of the heavy
rod m and the chisel n to take place unchecked, substantially as set forth and with
reference to Figs. 1 & 2.
4th. In a boring apparatus for deep borings in which the boring rods are rigid
and actuated from a crank, a crank motion in which the belt & (chain or rope) which
drives the crank a, is pressed down by the belt itself which effects the slackening of
the same and unchecked drop of the heavy rod m and chisel n substantially as set
forth and with reference to Fig. 3.
5th. In a boring apparatus for deep borings in which the boring rods are rigid

page_text: and actuated from a crank motion in which the belt (chain or rope) is under the
influence of a tightening pulley P, which is mounted eccentrically and performs one
revolution to one turn of the belt, so that owing to the eccentricity of the tightening
pulley the belt is slackened after the commencement of the descent of the boring
rods and thereby the drop of the heavy rod m and chisel n, substantially as
set forth.
6th. In boring apparatus for deep borings au elastically mounted beam B for the
purpose of preventing breakage, substantially as set forth and with reference to
Figs. 1 & 2.
7th. In boring apparatus for deep borings an elastically mounted beam B which
is actuated by means of a connecting rod p from the rotating crank a, substantially
as set forth and with reference to Figs. 1 & 2.
Dated this 3rd day of August. 1893.
F. BOSSHARDT & Co.,
4, Corporation Street, Manchester, Agents to Applicant.