IMPROVEMENTS IN STEAM PLOUGHING, TRACTION, MINING, PORTABLE, AND OTHER ENGINES."ATION left
Year: 1875

page_text: LETTERS PATENT to David Greig and Max Eyth, both of the Steam
Plough Works, Leeds, in the County of York, for the Invention of
"IMPROVEMENTS IN STEAM PLOUGHING, TRACTION, MINING, PORTABLE, AND
OTHER ENGINES."
PROVISIONAL SPECIFICATION left by. the said David Greig and Max
Eyth at the Office of the Commissioners of Patents, with their
Petition, on the 23rd February 1875.
We, DAVID GREIG and MAX EYTH, both of the Steam Plough Works,
Leeds, in the County of York, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN STEAM PLOUGHING, TRACTION, MINING,
PORTABLE, AND OTHER ENGINES," to be as follows:-
This Invention has for its object improvements in steam ploughing,
traction, mining, portable, and other engines.

page_text: reversing lever. But it has hitherto been found impossible to obtain
with such gears very high degrees of expansion and also a late cut off or
full steam if required. Thus especially when employing single cylinder
engines working with a high degree of expansion, the crank was liable
to stop in positions in which it was impossible to admit steam on either
side of the piston and the engine could only be started again by turning
the fly wheel by hand.
For engines which have to be stopped, reversed, and started frequently,
such as traction, steam ploughing, or mining engines, this defect is very
serious, and prevents the employment of highly expansive engines.
The first part of our Invention consists in such arrangements of the
reversing and expansion gear, that the gear not only admits of a high
degree of expansion, but also of giving full or nearly full steam after
stopping or reversing the engine for the purpose of starting the same
again, mainly in connection with steam ploughing, traction, mining, or
other engines which require frequently to be reversed.
In preference to other means for accomplishing this we employ a
valve carrying a plate on its back. The valve contains three chambers,
the central one leading away the exhaust steam, the two lateral ones
communicating alternately with the two ends of the cylinder. The ports
in the back of the valve are alternately opened and closed by the plate.
This plate moves freely with the valve as long as it is not prevented
from doing so by certain fixed stops which arrest its movement in the
direction in which the valve travels. The valve itself is moved by an
eccentric, working a rocking link, the link acting on the valve rod through
a block sliding in the usual slot.
The position of the block in the slot being altered, the valve can not
only be reversed in its motion, but also the length of its throw can be
changed, and this will cause the moment of the "cut off" to change
fromto of the stroke. The shorter the throw of the valve the
later the cut-off will take place, but when shortened beyond the length
necessary for admitting the steam during half of the stroke the plate
will no more close the ports in the back of the valve at all, and steam
will be admitted during the whole stroke. Thus by merely working the
block in the link, the engine can be reversed, the highest degrees of a
expansion can be given, and whilst reversing or at any other moment,
also full steam can be admitted to the cylinder.

page_text: The second part of our Invention consists of an improved feed water
heater. Hitherto it has been impossible to utilise the most convenient
place for a feed water heater, viz., the interior of the smoke box, because
the space inside the smoke box had to be kept free for cleaning the
boiler tubes in boilers of the locomotive type.
Our Invention consists in combining the feed water heater with the
smoke box door, so that when the door is opened the feed water heater
is moving out of the way. For this purpose the door is formed of two
plates enclosing a water-tight chamber divided into an upper and lower
compartment; both compartments are connected by a series of bend
water tubes protruding into the interior of the smoke box. The feed
water passes through the bottom hinge into and through the top hinge
out of this feed water heater, each hinge being provided with a suitable
stuffing box.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said David Greig and Max Eyth in the Great Seal
Patent Office on the 23rd August 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, wc, DAVID
GREIG and MAX EYTH, both of the Steam Plough Works, Leeds, in the
County of York, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of February, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto us, the said David Greig and Max Eyth,
Her special license that we, the said David Greig and Max Eyth, our
executors, administrators, and assigns, or such others as we, the said
David Greig and Max Eyth, our 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 STEAM PLOUGHING, TRACTION,
MINING, PORTABLE, AND OTHER ENGINES," upon the condition (amongst

page_text: others) that we, the said David Greig and Max Eyth, our executors
or administrators, by an instrument in writing under our, or their
hands and seals, or under the hand and seal of one of us or them, 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 Max Eyth, on behalf of myself
and the said David Greig, do hereby declare the nature of the said
Invention, and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following
statement thereof, that is to say :-
This Invention has for its object improvements in steam ploughing,
traction, mining, portable, and other engines.
Reversing and expansion gears combined have been constructed so as
to give a variable degree of expansion by altering the position of the
reversing lever. But it has hitherto been found impossible to obtain
with such gears very high degrees of expansion, and also a late "cut
off" or "full steam" if required. Thus, especially when employing
single cylinder engines working with a high degree of expansion, the
crank was liable to stop in positions in which it was impossible to admit
steam on either side of the piston, and the engine could only be started
again by turning the fly wheel by hand.
For engines which have to be stopped, reversed, and started frequently,
such as traction, steam ploughing, or mining engines, this defect is
very serious, and prevents the employment of highly expansive engines.
The first part of our Invention consists in such arrangements of the
reversing and expansion gear, that the gear not only admits of a high
degree of expansion, but also of giving full, or nearly full steam after
stopping or reversing the engine for the purpose of starting the same
again mainly in connection with steam ploughing, traction, mining, or
other engines which require frequently to be reversed.
In preference to other means for accomplishing this we employ a
valve carrying a plate on its back. The valve contains three chambers,
the central one leading away the exhaust steam, the two lateral ones

page_text: communicating alternately with the two ends of the cylinder. The ports
in the back of the valve are alternately opened and closed by the
plate. This plate moves freely with the valve as long as it is not
prevented from doing so by certain fixed stops which arrest its move-
ment in the direction in which the valve travels. The valve itself is
moved by an eccentric working a rocking link, the link acting on the
valve rod through a block sliding in the usual slot.
The position of the block in the slot being altered the valve can not
only be reversed in its motion, but also the length of its throw can be
changed, and this will cause the moment of the "cut off" to change
from 1th to 12 of the stroke. The shorter the throw of the valve the
later the cut-off will take place, but when shortened beyond the length
necessary for admitting the steam during half of the stroke the plate
will no more close the ports in the back of the valve at all, and steam will
be admitted during the whole stroke, thus by merely working the block in
the link the engine can be reversed, the highest degrees of expansion can
be given, and whilst reversing or at any other moment also full steam can
be admitted to the cylinder.
The second part of our Invention consists of an improved feed water
heater. Hitherto it has been impossible to utilize the most convenient
place for a feed water heater, viz., the interior of the smoke box, because
the space
inside the smoke box had to be kept free for cleaning the
boiler tubes in boilers of the locomotive type.
Our Invention consists in combining the feed water heater with the
smoke box door, so that when the door is opened the feed water heater
is moved out of the way. For this purpose the door is formed of two
plates enclosing a water-tight chamber divided into an upper and lower
compartment. Both compartments are connected by a series of bent
water tubes protruding into the interior of the smoke box. The feed
water passes through the bottom hinge into and through the top hinge.
out of this feed water heater, each hinge being provided with a suitable
stuffing box.
For the purpose of further explaining our Invention we proceed now
to describe the accompanying Drawings.

page_text: readily be removed from the smoke box for the purpose of cleaning the
boiler tubes, substantially as described.
In witness whereof, the said Max Eyth, have hereunto set my
hand and seal, this Eleventh day of August, in the year of our
Lord One thousand eight hundred and seventy-five.