IMPROVEMENTS IN APPARATUS FOR GETTING OR CUTTING MINERALS, AND IN APPARATUS FOR COMPRESSING AIR
Year: 1870

page_text: LETTERS PATENT to Alexander Morton Strathern, of Coatbridge, in
the County of Lanark, North Britain, Engineer, for the Invention
of "IMPROVEMENTS IN APPARATUS FOR GETTING OR CUTTING MINERALS, AND
IN APPARATUS FOR COMPRESSING AIR."
Sealed the 15th September 1870, and dated the 19th March 1870.
PROVISIONAL SPECIFICATION left by the said Alexander Morton
Strathern at the Office of the Commissioners of Patents, with his
Petition, on the 19th March 1870.
I, ALEXANDER MORTON STRATHERN, of Coatbridge, in the County of
Lanark, North Britain, Engineer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN APPARATUS FOR GETTING OR CUTTING
MINERALS, AND IN APPARATUS FOR COMPRESSING AIR," to be as follows, that is
to say:
:-
This Invention comprises various improvements in the kind of apparatus
for getting or cutting minerals in which the cutters are carried and
moved by an endless chain extended by a jib. And also improvements

page_text: in the apparatus for compressing the air by which such mineral getting
apparatus is usually worked, the latter improvements being also
applicable to apparatus for compressing air for other purposes.
The improved mineral getting apparatus comprises two cylinders
formed in the same line at the opposite ends of a casting, with their
inner ends open, and with a single-acting piston in each. The two
pistons are connected by rods to a tubular crank pin fixed to two discs
between which the rods work, and which are carried by means of external
journals. Through the tubular crank pin there passes a spindle having
three pinions fixed on it, and gearing with three internally toothed
wheels, one of which is fixed to or formed in the main casting,
whilst the second is fixed to or formed in the same casting with the
inner pulley of the endless chain, the third being on a pulley or barrel
which winds up a chain having one end fixed so as to produce the
progressive movement of the machine. The motion of the crank causes
the crank spindle to receive a rotatory motion from the fixed wheel, and
it imparts suitable motions to the other two wheels in consequence of
their differing from the fixed wheel in the numbers of their teeth. With
this gearing, which may of course be used with other reciprocating or
with rotatory engines, the requisite reduction of speed from the revolving
crank to the endless chain is obtained in a very direct and simple manner,
and with extreme compactness of parts. Piston valves are applied to
the cylinders, and instead of the valve rods passing through stuffing boxes
an additional piston is fixed on each rod to prevent communication
with the outside. Instead of the jib being forked at its outer end to
receive a single pulley, it is continued single to the extremity, and two
pulley discs are applied on each side of it, being fixed on a strong boss
turning in an eye in the jib end. This admits of the jib end being
shaped so as to give a much better and more extended support to the
endless chain.
In one modification the chain consists of single thick flat links
alternating with pairs of thinner links and jointed by pins held by
screwed in heads, but fitted so as not to turn in the eyes of the pair
links. The pulley discs are formed with projections which gear in on
each side of each single link and against the ends of the pair links. The
spaces between the pair links are thus left free and serve for inserting
and holding the shanks of the cutters, which are thus held in a superior

page_text: manner, and their cutting edges not requiring to overhang so much as
with other modes of fixing can be made more acute without risk of
running too far into the coal or other mineral as this is prevented by
the edges of the link, which are curved concentrically with the pulley
and bear against the previously cut surface of the coal. Packing rings
are applied to the pulley discs to prevent the access of coal dust to the.
inner working parts, which are also provided with oil reservoirs.
In another modification a common chain is employed and socket
pieces are welded into some of the links to receive the shanks of the
cutters, whilst the cutters are formed with shoulders to be supported on
guides at the sides of the chain and fixed to the jib. Two single acting
cylinders arranged as herein-before described are used as pumps for
compressing the air to work the mineral getting apparatus. The air
enters at the inner open ends and through valves in the pistons or
plungers, and passes through valves in the bottoms of the cylinders to
the pipe conveying it down the mine, with which arrangement the air is
very completely expelled from the cylinders at each stroke. Or the two
cylinders may be formed upon or fixed to a sole plate at convenient
inclinations, say at right angles to each other, and at angles of 45 degrees
of the circle to the sole plate, and may be worked by a bell crank lever
having its bearing on the sole plate so as to save the expence of sup-
porting pillar or entablature. A third arm on the bell crank lever may
be connected to a fly wheel and to a steam cylinder by which the pumps
are worked, or one of the inclined cylinders may be the steam cylinder,
the other one constituting the only compressing pump.
filed by the said Alexander Morton Strathern in the Great Seal
Patent Office on the 17th September 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
30 MORTON STRATHERN, of Coatbridge, in the County of Lanark, North
Britain, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her

page_text: our Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Alexander Morton Strathern, Her special licence
that I, the said Alexander Morton Strathern, my executors, adminis-
trators, and assigns, or such others as I, the said Alexander Morton
Strathern, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN APPARATUS FOR GETTING OR CUTTING MINERALS, AND IN
APPARATUS FOR COMPRESSING AIR," upon the condition (amongst others)
that I, the said Alexander Morton Strathern, my executors or
administrators, by an instrument in writing under my, or their, or one
of their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said Alexander Morton Strathern, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement in writing, reference being had to the
accompanying Drawings, that is to say :-
My said Invention comprises various improvements in the kind of
apparatus for getting or cutting minerals in which the cutters are carried
and moved by an endless chain extended by a jib. And also improve-
ments in the apparatus for compressing the air by which such mineral
getting apparatus is usually worked, the latter improvements being
also applicable to apparatus for compressing air for other purposes.
And in order that my said Invention, and the manner of performing
the same, may be properly understood I have hereunto appended two
Sheets of explanatory Drawings, to be herein-after referred to, and
representing mineral getting and air compressing apparatus as constructed
with my improvements. In these Drawings the same reference numerals
are used to mark the same or like parts wherever they are repeated.

page_text: Figure 1, on Sheet 1 of the Drawings, is a longitudinal vertical section
of my improved mineral getting apparatus; Figure 2 is a horizontal
section; and Figure 3 is a sectional end elevation. The apparatus
comprises two cylinders 1, 2, formed in the same line at the opposite
end of a casting which forms the framing and encases the various
working parts. The cylinders 1, 2, have their inner ends open, and they
are provided with single acting pistons 3, 4, which are connected by
rods 5, 6, to a tubular crank pin 7 formed on and between two discs 8, 9,
between which the rods 5, 6, work, and which are carried by means of
external journals 10 working in bearings, one in the bottom of the frame
casting and the other in the boss of a wheel 11, herein-after referred
to. Through the tubular crank pin 7 there passes a spindle 12 having
three pinions 13, 14, 15, fixed on it and gearing with three internally
toothed wheels 16, 17, 11, one 16 of which is fixed to the frame casting,
whilst the second 17 is fixed to the inner pulley 18 of the endless
chain 19, the third 11 being fixed to a pulley 20 which winds up a
chain having one end fixed so as to produce the progressive motion of
the machine. The motion of the crank 7 causes the crank spindle 12
to receive a rotatory motion from the rolling of the pinion 13 round the
fixed wheel 16, and it imparts suitable motions to the other two
wheels 17, 11, in consequence of their differing from the fixed wheel in
the numbers of their teeth. With this gearing, which may of course be
used with other reciprocating or with rotatory engines, the requisite
reduction of speed from the revolving crank 7 to the endless chain 19 is
obtained in a very direct and simple manner and with extreme
compactness of parts. Piston valves 21 are applied to the cylinder ports,
and instead of the valve rods 22 passing through stuffing boxes an
additional piston 23 is fixed on each rod to prevent communication with
the outside. The valves are worked by a lever 24 having one end acting
between adjustable blocks on the connected valve rods 22, whilst a block
on a pin on the other end is entered into an eccentric groove 25 in one 8 of
the discs. Passages leading the compressed air or other motive fluid to
and from the valve cylinders are formed in the frame casting in connection
with a valve chest 26, in which a common slide valve 27 formed with a
rack on one side and having in gear therewith a pinion on a spindle
with a hand wheel 28 is provided for transposing the communications
and so reversing the motion of the engine when required. The jib 29 by
which the endless cutter chain 19 is extended instead of being forked at

page_text: its outer end as heretofore to receive a single pulley is continued single
to the extremity, and two pulley discs 30 are applied on each side of it,
being fixed on a strong boss turning in an eye in the jib end 31. This
admits of the jib end being shaped so as to give a much better and more
extended support to the endless chain 19. The jib end 31 is socketed
into the body 29 and can be adjusted by screw nuts 32 to tighten the
chain. The inner end of the jib body 29 is made with a flange 33 to
bear upon a segmental surface formed on the frame casting.
The pulley
each side of
The spaces
In one modification of the chain shown in side view in Figure 4, and
in edge view and section in Figure 5, it is composed of single thick flat
links 34 alternating with pairs of thinner links 35 and jointed by pins 36
held by screwed in heads 37, but fitted each with a square neck to one
of the pair links so as not to turn in the eyes of those links.
discs 30 are formed with projections 38 which gear in on
each single link 34 and against the ends of the pair links 35.
between the pair links 35 are thus left free and serve for inserting and
holding the shanks 39 of the cutters 40, filling up pieces 41 being
rivetted in on each side of the cutter shanks 39. The cutters are held
in place by nuts 42 on screwed ends formed on their shanks and are
secured in a superior manner. Their cutting edges do not require to
overhang so much as with other modes of fixing, and can consequently
be made more acute without risk of running too far into the coal or
other mineral, as this is prevented by the edges of the links 35 which
are curved concentrically with the pulley 30 and bear against the
previously cut surface of the coal.
In another modification shown in Figures 6 and 7 a common link chain
is employed and socket pieces 43 are welded into or forged on the single
links to receive the shanks 39 of the cutters 40, and in some cases the
cutters are formed with shoulders to be supported on guides at the sides
of the chain and fixed to the jib.
Two modifications of my improved air compressing apparatus are
shown on Sheet 2 of the Drawings. In one shown in sectional elevation
in Figure 8, two single-acting cylinders 1, 2, arranged as herein-before
described are used as pumps for compressing the air. The air enters at
the inner open ends and through valves 44 in the pistons or plungers 3,
4, and passes through valves 45, in the inner ends of the cylinders to
the pipe 46 conveying it down the mine, with which arrangement the

page_text: air is very completely expelled from the cylinders at each stroke. The
mode of working the pumps will be easily understood from the Drawing.
The pump pistons 3, 4, are connected by two rods 47 between which
there works one end of a three-armed beam 48 connected by a link to a
cross pin fixed to the rods. The other end of the beam 48 works between
a pair of steam cylinders 49 whose piston rods are fixed to a single cross
head 50 connected to the beam by a connecting rod in the middle. The
third arm of the beam 48 is connected to a crank on the shaft of a fly
wheel 51.
In another modification the two air pump cylinders may be formed or
fixed to a sole plate at convenient inclinations, say at right angles to
each other, and at angles of 45 degrees of the circle to the sole plate, and
may be worked by a bell-crank lever having its bearing on the sole plate
so as to save the expence of supporting pillar or entablature. A third arm
on the bell-crank lever may be connected to a fly wheel and to a steam
cylinder by which the pumps are worked, or one of the inclined cylinders
may be the steam cylinder, the other one constituting the only com-
pressing pump and being in that case double-acting. These last.
mentioned arrangements are adopted in the modification shown in
Figure 9, but for convenience a pair of small steam cylinders 49 are used
so that the connecting rod may pass between them to the crank of the
shaft of the fly wheel 51. The pistons of the steam cylinders 49 as well
as those of the air pump 52 have small trunks and are connected by
short rods to the bell crank 48, both arms of which are forked at their
outer ends. The end of the fly wheel connecting rod is jointed within
the fork on a strong pin which projects outside of each cheek to receive
the end joints of the steam cylinder rods.
Having thus particularly described my said Invention, and the manner in
which the same is to be performed, I have to state that I do not restrict
myself to the precise details herein described or delineated, but that what
I believe to be novel and original, and claim as the Invention secured to
me by the herein-before in part recited Letters Patent is,—
-
1. The arranging or combining together of the parts of motive-power
mechanism for mineral getting or cutting apparatus substantially in the
improved mode herein-before described.
2. The constructing of the jib end and outer pulley or pulleys in the
improved mode substantially as herein-before described.

page_text: 3. The combining of the chain links and cutters in the improved
modes substantially as herein-before described.
And 4. The arranging and combining together of the parts of air com-
pressing apparatus in the improved modes substantially as herein-before
described.
In witness whereof, I, the said Alexander Morton Strathern, have
hereunto set my hand and seal, this Sixteenth day of September,
in the year of our Lord One thousand eight hundred and
seventy.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
A. MORTON STRATHERN. (L.S.)