Improvements in Mining Machines.
Year: 1895

page_text: Date of Application, 18th June, 1895-Accepted, 14th Sept., 1895
COMPLETE SPECIFICATION.
Improvements in Mining Machines.
I, JAMES ALEXANDER WIGGS, Junior, Manufacturer, of the City of
Birmingham, in the County of Jefferson, and State of Alabama, United States of
America, do hereby declare the nature of my invention for Improvements in
mining machines, 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 especially to mining machines which use a travelling
cutter-carrying chain fed automatically into the coal or other material which is to
be mined and withdrawn also by the feeding gear.
An important object of this invention is to supply simpler and more satisfactory
feeding and withdrawing mechanism and to lessen the wear and tear and risk of
breakage by permitting a part of the gearing to be inactive and therefore not
under strain.
Another important object is to keep the cutter-carrying chain and the pusher
head to which it is attached, fron shifting laterally out of its most effective
position.
:
To these ends and for the general improvement of the machine my invention
consists in the construction and combination of parts hereinafter particularly set
forth and claimed.
In the accompanying drawings:
Fig. 1. represents a perspective view of a machine embodying my invention;
Fig. 2 represents a transverse vertical sectional view, on a larger scale, of
the feeding and withdrawing mechanism, some of the parts being shown in
elevation;
Fig. 3. represents an elevation of a part of said mechanism, taken at right
angles to Fig. 2. 3
Fig. 4. represents a detail perspective view of the three gear wheels which mesh
together and the parallel shafts which carry them, the latter being broken away;
Fig. 5. represents an external view of the combination clutch and gear;
Fig. 6. represents a transverse vertical section through the fixed frame and
sliding frame of the machine, showing in elevation a part of the devices carried by
the latter frame and especially the feeding pinions engaging the racks;
Fig. 7. represents a side elevation of the pusher head, cutter-carrying chain and
sprocket wheel; and Figs. 8, 9, 10, and 11 represent detail views illustrating the
devices for preventing the lateral shifting of the pusher head or cutter head.
A designates the relatively fixed frame of the machine provided on the inner
faces of its sides with guide flanges a for the longitudinal movement of the sliding
frame B toward and from the coal that is to be cut. Cogged racks a parallel
with the said flanges, are also formed with or attached to the said inner faces.
C designates the two engines or other motors which are mounted on the said
sliding frame, as is also the driving shaft D, that they operate. This shaft carries
a bevel pinion E, which meshes with a large bevel gear wheel F, that is fast on a
shaft G at right angles to the said driving shaft and preferably vertical. This
shaft G like all those herein described, has its bearings in the said sliding frame, a
part of which appears in Fig. 2. It is provided with a metallic bushing g and an
annular facing, of similar material surrounds the reduced upper end of the said
shaft, being interposed between the hub of the said bevel wheel and the top of the
said bearing and bushing as well as the shoulder of the said shaft.
A sprocket wheel H is detachably secured, preferably by screw threads h, on

page_text: the lower end of this shaft and engages and drives a cutter-carrying chain I
provided with knives or cutters i and running between the upper and lower plates
of a pusher head J. These plates are at first bent. down at ; to the level of the
sprocket wheel, and then extend horizontally forward so that the cutting will be
parallel with the floor of the coal seam and at the lowest attainable level, wasting
none of the coal.
A downwardly facing bevel gear wheel K is fastened to the said bevel wheel F
and of course turns therewith, meshing continually with the bevel gear face L' of
combined gear and clutch L, that is loose on a shaft M arranged at right angles to
the said shaft G and provided with bushings M' at intervals. The middle part of
the outside of the said combined gear and clutch is provided with or constructed to
form a spur gear L2 and the end of it away from the said face L' is recessed
conically at L to form a clutch surface for receiving a conoidal sliding clutch N,
which is feathered on the said shaft M by a spline m, and of course turns therewith.
The middle part of this clutch is constructed with an annular groove N¹, to
receive a shifting lever O, and the other end of the said clutch is provided with a
projecting part N2 adapted to enter a corresponding recess p in the side of a large
gear wheel P which is loose on the said shaft, and thereby clutch the said wheel.
The spur gear L2 meshes with a gear wheel Q' on a shaft Q which carries also
a pinion Q2. A similar pinion Q³ on a shaft Q meshes continually both with the
pinion Q and the gear wheel P.
The shaft M carries also a worm R which is fast thereon and meshes with a
worm wheel S on a short transverse shaft St, provided at its ends with the feeding
pinions S which engage the fixed racks a' so as to feed the sliding frame and
cutter-carrying chain toward or from the coal, according to the direction of rotation
of the shaft M.
This is determined by the position of clutch N.
When the said clutch, as in
Fig. 2., engages the combined gear and clutch L, the shaft M. and worm R being
driven directly thereby, turn so as to feed the sliding frame forward and to cause the
cutter carrying chain to enter more and more deeply into the coal, while the gear
wheel P is loose on its shaft, and the intermediate gears QQQ³, though
continuously in engagement and rotation are under no strain.
When the clutch N is shifted into engagement with the wheel P, the combined
clutch and gear L' turns on the shaft M, without directly driving it, but drives the
said shaft in the reverse direction through the train of gears QQ² Q³ and P, the
latter being then fast on the said shaft by the said clutch engagement.
The shifting of the said clutch is automatically effected at the proper intervals
by the contact of the said shifting lever with stop T fixed on the stationary frame A
or otherwise supported. From the action of these and the devices before described,
it results that the cutter-carrying chain is first fed steadily forward into the coal
until the under cutting is complete, then withdrawn to its first position, these
reciprocatory actions being repeated as the machine is moved along the face of
the coal.
The main frame A of the machine has a cross bar A' extending under the front
part of it and attached at the ends to the side bars of the said frame on the outside
thereof. On this I attach a casting U having two upwardly extending guide
lugs u, as in Fig. 1, or two lugs u' similarly arranged, may be attached directly to
the said cross bar, as in Fig. 8. In either case the said lugs receive between them
the pusher bar or pusher head V of the guide chain. This bar extends to the
front of the said chain and is attached to the casing U¹ which protects the same and
in which the guide rollers U of the said chain are journaled. The front of the
said chain is open to allow the action of the cutters on the coal. The pusher bar
casing, rollers U and cutter carrying chain of course, all move together, with the
sliding frame or carriage B. The lugs prevent the pusher head from moving
laterally under pressure or strain, and thereby keep the cutter chain in position for
working properly. Such strain occurs when the cutters come in contact at one
point or another with a bed or mass of sulphur or other hard matter.

page_text: To further provide against such shifting, I supply to the middle or any other
convenient part of such casing a sprocket wheel W having journals W whic:
extend above and below its bearings therein, the extended ends being provided with
radial cutter blades X which cut two parallel straight grooves in the coal, on
groove being directly below and the other directly above the sprocket wheel Wa
the latter is driven by the said cutter carrying chain, and the said chain is fel
forward. Of course the walls of said grooves, as shown in Fig. 10 will preven..
the cutter or blades X from leaving them and will equally resist any sidewise
tendency of the said pusher head and chain.
This however, causes now and then an injurious strain on the cutters or blades X
and to relieve this and still more effectually to guard against shifting, I provide
the pusher head in the rear of the sprocket wheel W with guide blocks Y Z
attached to the same respectively above and below it in line with the said grooves
in the coal, on the proper level to enter the same, and of such width as to fill or
nearly fill them from side to side, though free to move easily forward and backward
therein. Of course either one of the said blocks may be dispensed with, as they
are duplicates of each other in construction, arrangement and function; but both
together are more effective.
Having now particularly described and ascertained the nature of my said inven--
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. In a mining machine, a combined clutch and gear having two sets of cog-teeth
and a friction clutch surface, in combination with a driving shaft and intermediate
gears engaging one set of such teeth, a gear wheel and an intermediate train of
gears meshing with the other set of the said cog teeth, a shaft on which the said
gear wheel and the said combined clutch and gear are loosely mounted, a clutch
feathered on the said shaft and adapted to engage the said gear wheel and the said
clutch and gear alternately, cutting devices, and mechanism driven by the said
shaft for feeding forward the said cutting devices and withdrawing them alternately
substantially as set forth.
2. In a mining machine a combined clutch and gear having two sets of cog-teeth
and a friction clutch surface, in combination with a driving shaft and intermediate
gears engaging one set of such teeth, a gear wheel and an intermediate train of
gears meshing with the other set of the said cog-teeth, a shaft on which the said
gear wheel and the said combined clutch and gear are loosely mounted, a clutch.
feathered on the said shaft and adapted to engage the said gear wheel and the said
combined clutch and gear alternately, cutting devices, mechanism driven by the
said shaft for feeding forward the said cutting devices and withdrawing them
alternately, a shifting lever engaging the said clutch and fixed stops arranged to
be struck by the said lever to cause the shifting of the clutch automatically from.
the said gear wheel to the said combined clutch and gear or back again as the
movable frame approaches either end of its travel, substantially as set forth.
3. In a mining machine, a combined clutch and gear having a set of bevel teeth,
a set of spur teeth and a friction clutch surface, in combination with a bevel.
wheel K engaging the said bevel teeth, a gear wheel F fast to and turning with
the said wheel K, a driving shaft and gear meshing with said wheel F, a loose
gear wheel P on the shaft M with the said combined clutch and gear, a gear
wheel Q engaging the spur gears of the latter, gearing from the wheel Q₁ to the
wheel P, a clutch arranged for alternate engagement with the wheel P and the
combined clutch and gear aforesaid and feathered on the shaft M between them, a
transverse shaft carrying pinions mounted in the movable frame which bears the
cutters and geared to this shaft M, and a pair of racks attached to the fixed frame
of the machine and arranged to be engaged by the said pinions, substantially as
and for the purpose set forth.
4. In a mining machine, a movable frame a pusher bar attached thereto,.
travelling cutters carried by the said pusher bar, and mechanism for actuating the

page_text: said movable frame and cutters, in combination with a fixed frame, provided with
guide ways for the said movable frame and also with a pair of raised lugs arranged
on each side of the pusher bar for bracing the same against lateral strain of the
cutters, substantially as set forth.
Dated this 25th day of April 1895.
JAMES ALEXANDER WIGGS, JR.