Improvements in Electric Rock-drills.
Year: 1889

page_text: COMPLETE SPECIFICATION.
Improvements in Electric Rock-drills.
I, IMLE E. STOREY, of Boulder in the County of Boulder and State of Colorado
United States of America, Electrician, 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 :-
My Invention relates to electric drills with particular reference to drills in which
the tool rotates in distinction from those in which the tool reciprocatos. The
object of the Invention is to provide a device of this kind which shall be as compact
as possible, easy of manipulation, simple in construction and adapted to feed the
drill either automatically or by hand.
The Invention consists briefly of a rectangular frame having mounted upon it on
suitable ways a supplemental sliding frame carrying an electric motor. The drill
tool is connected directly with the armature shaft of the motor and is hollow to allow
the passage of water or other lubricant to the drill point. The details of construction
and operation will be clearly set forth in the following description reference being had
to the accompanying drawings, in which
Fig. 1 represents a side olevation of the apparatus parts of the same being shewn in
section.
Fig. 2 represents a plan of the device; and
Figs. 3, 4, and 5 represent details.
Referring to the drawings by letter, A represents the main frame of the apparatus.
It is supported upon a tripod from trunnions A¹ centrally located. There is mounted
within this frame a second or supplemental frame B, which slides or reciprocates
within the frame- A. To facilitate the sliding movement, anti-friction wheels or
rollers are located at the four corners of the frame B, and they bear upon tracks
formed in the frame A. The electric motor C, is rigidly mounted in the frame B.
The field magnets Care secured to an annulus c, the latter in turn being bolted to
the frame B, as shown at c', c. The drawing shews but two field magnets. It is
obvious however that any desired number may be placed radially within the ring
and secured in the same manner as the two mentioned.
This
The armature C is mounted on a hollow shaft C³ and this shaft passes through
bearings in each end of the frames A and B. The lower bearing on the frame B is
a double one, one part being a ball bearing to receive the thrust from the tool and
the other being a smooth bearing in which the shaft rotates. The tool D, which is
ordinarily diamond pointed is secured to the shaft by screw threaded connections or
clamped in any suitable way. At the upper end of the frame A, the shaft C³ passes
through a water tight stuffing box e into a sleeve or water chamber E.
chamber has a fitting at the upper end for connecting a hose pipe leading from
any suitable water supply. The extreme upper end of this shaft is provided with
a valve e as shewn in Fig. 4. This valve has a seat within the shaft and its
upwardly extended stem is surrounded by a spring the tension of which may be
adjusted by a nut e*. This spring normally tends to hold the valve against its seat,
but the pressure above forces the valve from its seat and allows the water to pass
into the passage below and thence to the drill point. Thus the quantity of water
admitted to the hollow shaft and to the drill point may be regulated by adjusting the
spring controlling the valve.
shewn in Fig. 2 for the
The said shaft is provided
length below the bearing.
threaded jaws f, Fig. 5,
The frame A, at the top, has a lateral extension a,
purpose of supporting a bearing for a shaft F Fig. 3.
with a hand wheel F¹, and is screw threaded its entire
The shaft passes downward through a pair of internally
which are pivoted to a bracket f' bolted to the annulus c which supports the field
ID 1

page_text: maguets. There is also hung on this. bracket a disk 2 which is provided with
eccentric slots f³ engaging with studs in the outer ends of the pivoted jaws f. The
disk has a handle by which it may be rotated to throw the jaws out or away from the
screw shaft in an obvious manner. By this arrangement of screw and clutch, the motor
and its supporting frame together witli the shaft and tool may be fed back and forth by
hand as fast as the nature of the case requires. When it becomes necessary to
change the tools or to remove the whole apparatus, or for any other purpose, the
pivoted jaws may be thrown out of engagement with the screw and the motor frame
moved back and forth at will.
Besides this hand feeding device, I have also provided an automatic feed which
ordinarily will be used in preference to the hand feed. This consists in a roughened
disk Fig. 3 rigidly secured to the drill shaft. Upon the upper face of this disk
bears a friction roller g' of leather or other suitable material, which is mounted on
the end of a short shaft g secured in bearings to a bracket from the frame B. The
shaft is provided with a worm which gears into an exterior sprocket formed
upon an internally threaded sleeve g. Through this last mentioned sleeve the shaft F
passes and is adjusted up and down by means of the motion communicated from the
disk 9 in an obvious manner.
It is designed to cover the whole apparatus with a suitable covering or casing of
sheet metal, leather, or other suitable material, to prevent dust and water from falling
upon the machinery.
It is obvious that the details of construction of the machinery may be varied
somewhat without departing from the principle of my Invention.
I therefore
wish it to be understood that I do not limit myself to the precise construction
described.
. Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is :-
(1) In an electric drill; a main frame provided with tracks or ways and an
upwardly extending water reservoir a supplementary frame capable of sliding in the
main frame, an electric motor provided with a hollow shaft and mounted in the
supplemental frame, and a drill tool, all constructed and arranged and operating
substantially as herein before described with reference to the accompanying
drawings.
(2) In an electric drill; a main frame provided with a water chamber in
combination with a supplemental frame adapted to slide within the main frame and
carrying an electro-motor having a hollow shaft extending beyond the supplemental
frame and entering the water reservoir; substantially as described with reference to
the accompanying drawings.
(3) In an electric drill; the combination and arrangement with a sliding frame
carrying the rotating tool, of a friction disc, a friction wheel and suitable worm
gearing operated by the rotary shaft and connected to the sliding frame in such a
manner that the rotation of the shaft will cause the sliding movement of the said
frame; substantially as herein before described.
Dated this 5th day of August AD 1889
WILLIAM E.. HEYS,
Agent for the Applicant.