Improvements in Mining Machines.
Year: 1893

page_text: Date of Application, 2nd Nov., 1893-Accepted. 17th Feb., 1894
CUMI LEIE DI MUITIVATION.
[Communicated from abroad by JOSEPH ANDREW JEFFREY, of Columbus,
County of Franklin and State of Ohio, in the United States of America,
Manufacturer.]
Improvements in Mining Machines.
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane in the
County of London Chartered Patent Agent 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 :-
Fig. 1 is a side elevation showing the general outlines of the principal parts of
the machine when in operation.
Fig. 2 is a side elevation on a larger scale showing more of the details.
Fig. 3 is a longitudinal section, the motor being removed.
Fig. 4 is a plan view showing more particularly the shafting and gearing at the
rear end of the machine.
Fig. 5 is a cross section on the line x-x, Fig. 2.
Fig. 6 is a plan of the machine.
Figs. 7 to 35 show details.
Inasmuch as those details of the machine which pertain to the cutter bar, the
cutters, the driving chain, the carriage, the mountings on the carriage for the
cutter bar, the bed, the platform or plate which supports the gearing and shafting,
have been clearly illustrated and fully described in my earlier Patent Application
No. 19714 of 1893, it will not be necessary to here, again, describe such details, the
present invention relating mainly to the new and useful features incident to the use
of a motor of the sort herein.set forth.
Reference may be made to the aforesaid earlier Patent for such description
concerning said parts and which may be considered as a part hereof for the purpose
of getting a full understanding of the corresponding elements in the present
machine.
However, I will summarise the same as follows.
There is a bed having grooved side bars A, A, which are joined by cross
bars B, B, B. There are longitudinal top bed bars B carrying downward turned
racks C, and bolted to the top edges of bars A, A. The bed rests on shoes B³ B³,
and can be readily moved on the ground by applying crow bars to the cross bar T
having hooked projections t, t.
In this bed a sliding carriage is mounted, it having side bars E, E, cross bars E³, E³,
and zig zag bars E¹.
F is the cutter bar at the front end of the carriage and mounted on the
bars E, E, in two bearings, it being provided with cutters which are thrust
directly forward, and are rotated in vertical planes. H is the cutter bar driving
chain, having links with curved edges, engaging with sprocket teeth cut in
the bar F.
The cuttings are drawn out by the chain H, and by special chains I', 1', the
latter being supported on the cleaner shaft I, just behind the cutter bar. The
cleaner chains l'extend back to the supporting wheels 1'in the hangers 1* adjustably
secured to the rod I held on the front side of the motor.
J is a plate or platform secured to the rear end of the carriage bars E.
It carries the motor and all the shafting and gearing, it being formed with a central
aperture J' which permits the gearing to be lowered.. This part and all those

page_text: supported thereon can be adjusted relatively to the cutter bar by the screws at e, so
that the chains can he kept properly taut.
K is the chain driving shaft having chain teeth k for chain H. and wheel K' for
chain I. It is mounted in bushings set in recesses on platform J. It carries
wheel K driven by shaft P, and wheel P.
When shaft K is revolving, it will turn the cutters in the direction of the
arrow.
The carriage must be advanced on the bed when the cutter bar is operating
and such advancing is effected as follows. L is a second shaft on platform J,
having a worm' to give slow speed for feeding the carriage, and a bevel wheel
for rapid speed to pull the carriage back. Shaft M is driven by worm slowly
through worm wheel m, and carries a worm m¹. This shaft is mounted in a tubular
bracket M'. O is a faster shaft for receding the carriage, it also being driven by
shaft L through bevel gears and o, and it is provided with a worm o', its tubular
bracket being shown at O¹.
The slow motion of shaft M and the rapid motion of shaft O are alternately
taken to the reversible carriage moving shaft N. This carries a clutch N', and
pinions N2, the latter engaging with the aforesaid racks C. Shaft N also has two
loosely mounted worm wheels n and n' which are continuously driven at different
speeds and in opposite directions by the aforesaid worms m' and o'.
Q is a lever keyed to a shaft Q1, and having a pinion Q² engaging with a rack
plate Q3, the latter having a pin Q in the groove of clutch N'. The operator
with these can exert a powerful leverage in moving the clutch, and this is necessary
when the parts are under pressure. The clutch can be automatically moved by the
lever R arranged to impinge on the abutment R', in the manner described in the
aforesaid Patent.
From fifteen to twenty horse power is necessary to rotate the cutters, and force
them forward. A power mechanism of twenty horse at a slow speed makes the
machine very heavy. But it cannot be heavy as the whole apparatus must be
moved every few minutes by a man and a boy. Hence a high speed power mechanism
is necessary.
The only mechanism for this prior to the present invention comprised two
high speed, reciprocating, steam engines, with pistons making six hundred to eight
hundred strokes per minute. The jars and blows of this great number of strokes
make it always difficult and sometimes impossible to operate the machine, for the
engine strokes throw the cutters back from the coal, and interfere with the exertion
of a steady and continuous pressure.
After long experiment, I have found that a perfectly smooth rotation of the
cutter bar can be attained by use of a continuously rotating armature actuated by
electro-magnetism, as such armature will not only apply motion continuously, but
moreover, have a high momentum which is experienced through all of the movable
parts, including each of the heavy chain links at h, h' and the cutter bar, notwith-
standing its short radius. In machines having the reciprocating engines, the cutters
frequently stop the engine entirely, when they strike an unusually hard substance
as there is no momentum in such engines. It is impracticable to apply a fly-wheel
as the machine must be of little weight, and very compact so that they can be
manipulated in the low rooms of the mines.
Hence even with high power reciprocating engines, the cutters rotate unevenly, and
as said, frequently stop the whole machine. I have found that the continuously
rotating armature of an electric engine of considerably less power than that of the
reciprocating power engines not only imparts sufficient energy to the cutter bar, but
particularly compels it to rotate uniformly even though layers of slate in the bed of
coal are struck by the cutters, as the momentum of the rotating armature overcomes
the tendency of the numerous chain links, the cutters and other parts to respond to
the variations in resistance met by the cutters.
The motor is indicated by S, it having an armature S¹ as large as is practicable,
so as to impart momentum as well as rotation. The armature shaft carries pinion-S³.

page_text: which revolves at a very high speed, so that a light motor can be used. To reduce
this speed the large wheel P1 is used, it being situated outside of the bed, so that it
can extend below the top of it without interference.
It will be seen that the motor is arranged so as to preserve the balance of the
machine, and hold it steady on the ground. The motor acts as a brace for the
carriage frame and the shafts thereon, and also as an abutment for the reactionary
thrust of the cutters. It covers and protects the gearing on platform J, and prevents
the entrance of cuttings or material that might choke the wheels. It moves
forward with the cutter bar at a fixed distance therefrom, and therefore always
applies power uniformly.
Notwithstanding the fact that the armature is rotated with high speed, and
cannot be reversed without detriment, yet the carriage can be reversed in its
movements ou the bed very easily by the clutch lever, and the power multiplying
device at Q, Q³ and Q.
I prefer the arrangement of the motor shown, as I can thereby have the
commutator and its adjuncts extend in one direction, and the armature gearing
extend in the opposite direction, transversely of the bed. Moreover, I can take
the power down to the shafting beneath the motor, through the medium of straight
spur gearing which conveys it with the utmost economy, avoiding the necessity
of bevel gearing, or of worms, either of which is wasteful of power, as is well
known. And in a machine of this class every unit of power must be saved which
is available.
It will be seen that the motor is, in another respect, advantageously arranged,
namely in respect to the carriage moving shaft N and its adjuncts, they being
behind the motor, so that the operator can have ready access both to the lever Q,
and to the current controlling devices. The latter comprise a resistance box V
which is secured to the rear side of the motor, and the lever V', which is in easy
reach of the operator when standing where he can control the movements of the
carriage through the lever Q.
Having now particularly described and ascertained the nature of the aforesaid
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
1. In a mining machine of the class described, the combination of the bed, the
carriage, the rotary cutter bar across the front end of the carriage, the chain
driving said cutter bar, speed reducing gearing driving said chain, and the electric
motor on the carriage having a continuously rotating armature, in contradistinction
to a reciprocating power mechanism, connected to said gearing, whereby continuous
motion and momentum are imparted to the rotary cutter bar.
2. In a mechanism of the class described, the combination of the bed, the cutter
bar at the front, the sliding carriage supporting the said cutter bar in two bearings,
the driving chain for the bar, the platform at the rear end of the carriage for the
motor and gearing, the chain shaft on said platform, the intermediate shaft above
the chain shaft and projecting beyond the sides of the bed, the electric motor
having a continuously rotating armature shaft geared to the intermediate shaft
outside of the bed.
3. In a mining machine of the class described, the combination of the portable
bed, the carriage sliding on said bed, the cutter bar at the front end of the
carriage and supported thereon in two bearings, the plate or platform at the rear of
the carriage, the electric motor on said carriage having a continuously rotating
armature shaft, the chain driving shaft and the carriage moving shaft both beneath
the motor, and the intermediate shaft extending from points outside of the motor
to points beneath the same, and geared to the aforesaid shafts under the motor,
substantially as set forth.
4. The combination of the bed, the carriage sliding thereon, the cutter bar at the
front end of the carriage, the chain for actuating said bar, the electric motor, having
a continuously rotating armature shaft arranged transversely of the carriage,

page_text: whereby the commutator can extend in one direction over the bed, and the gearing
can extend in the opposite direction, and whereby straight spur gearing can be
employed to transmit the power from the armature to the gears and the shafting
beneath the motor, substantially as set forth.
5. The combination of the bed, the carriage sliding thereon, the cutter bar at the
front of the carriage, the motor secured upon the carriage at the rear end, the
carriage advancing mechanism situated behind the motor, the shafting beneath
the motor, the continuously rotating armature shaft, and the intermediate shaft,
conveying power from outside of the motor downward to the shatting under the
motor, substantially as set forth.
Dated this 2nd day of November 1893.
ABEL & IMRAY,
Agents for the Applicant.