Improvements in Electric Machines for Drilling, Boring, Grinding, and the like.
Year: 1891

page_text: ate of Application, 16th Oct., 1891-Accepted, 28th Nov., 1891
COMPLETE SPECIFICATION.
Improvements in Electric Machines for Drilling, Boring, Grinding,
and the like.
I, OLOF LINDERS of Gothenburg in the Kingdom of Sweden, 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:-
My invention relates to an electric drilling or boring machine which has a spindle
adapted to be displaced relatively to the electric motor and passing through the
hollow armature shaft, the motion of the latter being transmitted to the said spindle
in such a manner that the speed of this spindle will differ from that of the
armature.
The accompanying drawing represents a side elevation partly in section of my
improved drilling or boring machine.
This machine comprises an electric motor having a frame and magnet formed of
two castings a and b and magnet cores c and d upon which the pole pieces e and f
are secured. The armaturet and commutators are fixed upon a hollow shaft g held
in bearings provided in the castings a and b.
By sending an electric current through the said motor the shaft g is caused to
rotate in one or the other direction, and thereby imparting rotary motion also to
the spindle h.
This spindle is adapted to rotate and to be displaced in the hollow armature
shaft g. The motion of the armature is transmitted by means of a toothed pinion i
fixed on the armature shaft and gearing with the toothed wheel & which is integral
with the pinion and fixed on the shaft o by means of a set screw v.
The pinion/
engages with the toothed wheel m driving the aforesaid spindle h which can be
displaced in the wheel m. A key is fixed in the wheel m and can slide in a groove
formed in the spindle h.
I feed the above mentioned spindle by means of a cap u screwed upon the tubular
projection on the bracket h². Upon this cap is fixed the hand wheel ŕ connected
with the spindle which may thus be fed by hand. An automatic feed of the spindle
is effected through the medium of the toothed wheels p and 9, of which the former p,
may be displaced on the shaft o which likewise turns the wheel and the latter
arranged on the cap u.
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If it is desired to increase the speed of the spindle in order to obtain the same
speed as that of the armature shaft, the screw is loosened and the wheels k and l
are displaced on the shaft o so that the wheel k shall also gear with the pinion n
which is made in the one piece with the wheel m the latter owing to the displace-
ment of the two wheels above mentioned being brought out of gear with the wheel l.
In this way a direct coupling of the armature shaft g and spindle h is effected which
uay be desirable for drilling small holes, or for fixing a circular saw, a grinding
wheel or the like upon the spindle h in order to use the machine for other purposes
than drilling or boring.
The pole pieces e and fare provided with trunnions x and y by which the machine
may be secured to the work through the agency of magnetism in case the work
consists of material adapted for this purpose. The machine is moreover supported or
suspended in a suitable manner depending upon the nature of the work and the
local conditions.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I claim is :-
3 *11
inding and the like characterized

page_text: by the spindie which can be displaced in the hollow armature shaft being adapted
to rotate by means of gearing connected with the said armature shaft at a speed
differing from the speed of the latter.
Second. In the machine characterized in the first claim the arrangement of gearing
between the armature shaft and the spindle characterized by the fact that the said
shaft and spindle are provided with pinions and n of the same size placed close to
each other the pinion n being integral with a toothed wheel m and that a toothed
wheel (k) fixed on an auxiliary shaft can be brought into gear with one or both
pinions and n when a pinion integral with the said wheel k either gears or does
not gear with the said wheel m for the purpose of enabling the spindle to be rotated
at the same speed as or at a different speed from that of the armature shaft.
Third. In the machine characterized in the first claim the device for feeding the
spindle either by hand or automatically, which comprises a cap a connected with
the end of the spindle and screwed upon a prolongation h¹ on one of the brackets
for the spindle this cap carrying a hand wheel and a toothed wheel with which may
engage a pinion fixed upon a shaft forming part of the gearing.
Dated this 16th day of October 1891.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.