IMPROVEMENTS IN GAS MOTOR ENGINES
Year: 1883

page_text: LETTERS PATENT to Francis William Crossley of Great Marlborough Street
Manchester in the County of Lancaster for an Invention of "IMPROVEMENTS
IN GAS MOTOR ENGINES"
PROVISIONAL SPECIFICATION left by the said Francis William Crossley
at the Office of the Commissioners of Patents on the 21st June 1883.
FRANCIS WILLIAM CROSSLEY of Great Marlborough Street Manchester in the
County of Lancaster "IMPROVEMENTS IN GAS MOTOR ENGINES"
My Invention relates to an arrangement and construction of double or multiplo
gas motor engines of the kind commonly known as the "Otto" type, the main
object which I have in view being to equalise the action of such engines whilst
retaining a compact and simple form. For this purpose I place side by side within
one water casing two working cylinders, and connect both their pistons to a single
crank. I provide for the two cylinders a single slide for supply and ignition, so
arranged that while the piston of the one cylinder is making its outstroke drawing
in the combustible charge, the piston of the other, also making its outstroke, is
being propelled by the combustion of the charge previously drawn in, and while
the former piston is making its instroke compressing the charge in its cylinder, the
other, also making its instroke, is discharging exhaust. Four cylinders may be
thus made to act successively in the cycle of operation, and in such a case it is
convenient to connect all four pistons to ono crank, two of the cylinders being
arranged on one side of the crank shaft and two on the opposite side, so that the
outstrokes of the pistons of the one pair correspond with the instrokes of the
pistons of the other pair.
The slide valve employed for the pair of cylinders is made with a supply passage
in its middle which opens to the supply ports of the two cylinders alternately, and
with igniting passages near the ends of the slide by which the charges of the
cylinder are alternately ignited.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Francis William Crossley in the Great Seal Patent Office on the
19th December 1883.
FRANCIS WILLIAM CROSSLEY, of Great Marlborough Street Manchester in the
County of Lancaster "IMPROVEMENTS IN GAS MOTOR ENGINES"
My invention relates to an arrangement and construction of double or multiple
gas motor engines of the kind commonly known as the "Otto" type, the main
object which I have in view being to equalise the action of such engines whilst
retaining a compact and simple form. For this purpose, I place side by side, within
one. water casing, two working.cylinders, and connect both their pistons to a single
crank. I provide for the two cylinders a single slide for supply and ignition, so
arranged that, while the piston of the one cylinder is making its outstroke drawing
in the combustible charge, the piston of the other, also making its outstroke, is
being propelled by the combustion of the charge previously drawn in, and while
the former piston is making-its instroke comprossing the charge in its cylinder, the.
other, also making its instroke; is discharging -exhaust. Four cylinders may be
thus made to act successively in the cycle of operation, and. in such a case, it is
convenient to connect all four pistons to one crank, two of the cylinders being
arranged on one side of the crank shaft, and two on the opposite side, so that the
outstrokes of the pistons of the one pair correspond with the instrokes of the
pistons of the other pair.
The slide valve employed for the pair of cylinders is made with a supply passage
in its middle which opens to the supply ports of the two cylinders alternately, and
with guiting passages near the ends of the slide by which the charges of tho
cylinder are alternatoly ignited.
DESCRIPTION OF THE DRAWINGS
Fig. 1 is a side elevation and Fig. 2 is a plan of a twin gas motor engine
according to my invention; Figs. 3 and 4 shew to an enlarged scale respectively,
an end view, and a sectional plan of the cylinders, slide and working gear for the
slide and valves. The one crank A is linked by connecting rods B to the pistons
of the two cylinders C and D so that those two pistons always move together.
The two cylinders C and D are placed side by side within one water casing E.
Each cylinder has at its end a port or passage F, G for admission and ignition of
its charge, and has also a passage H I leading to an exhaust valve. The facing of
the ports F G has a central gas and air supply passage J, divided by a mid-rib.
The slide K is pressed against the casing by a cover L pressed by springs . In
the slide, there is a central supply cavity M and through it there are also two
ignition passages N O, and in the cover L there are two cavities P Q in which
external flames are kept burning. The slide K is caused to reciprocate by connec-
tion with a crank on a countershaft R which is driven by gearing at half the
speed of the engine shaft, so that the slide K makes a stroke in one direction during
one revolution of the crank, and a stroke in the opposite direction during the next
revolution of the crank. On the shaft R there are a pair of cams, which, acting
successively on a roller mounted on a lever S open the gas supply valve in opposi-
tion to a spring 8. The gas valve communicates with the passage J in which the
mixture of gas and air takes place. The roller on the lever S can be slid to and
fro along its axle by a lever I worked by the governor so as either to come in the
path of the cams when the engine is working.at moderate speed, or to be moved
out of range of the cams when the engine works too fast, in which case, the gas

page_text: supply valve is not opened. On the countershaft R there are two other cams U
and V, which, by acting on rollers mounted on levers and v open the two exhaust
valves by which the passages II and I communicate with the discharge. The
cavity M and the ignition passages NO in the slide K are so situated relatively to
the ports F G and J, and to the cavities PQ, and the movements of the slide K and
of tho levers u v are so timed, that, while the two pistons are making their forward
stroke, the one is drawing into the one cylinder C, a charge of fluid supplied to it
from J through one branch of M, and the other is being propolled by the expansion
of the charge in its cylinder D, resulting from its ignition by passage of flame
from through O. When the pistons are making their back strokes, that in C is
compressing the charge previously drawn in, while that in D is expelling the
products of previous combustion by the passage I, the valve of which is then open.
During the next forward and backward strokos of the pistons, D receives its supply,
and then has it compressed, while C has its piston propelled by expansion of its
charge, and then has the products of combustion expelled. Thus, when the engine
is normally working, in every revolution of the crank there is one active propelling
stroke of the one or the other of the two pistons. By widening somewhat the
crank A room may be obtained for the ends of two connecting rods extending, in
the direction opposite to those marked B, to the pistons of two cylinders operating
like C and D, so that in each revolution of the crank there may be two propelling
piston strokes, one in each direction.
Having thus described the nature of my invention and in what manner the saine
is to be performed, I claim in respect of gas motor engines of the kind known as
the "Otto" type :―
First. In combination with one crank, two pistons moving together in two
cylinders placed side by side in one casing and having their ports and passages so
governed that in each forward stroke, when normally working, one of the two
pistons is propelled by the expansion of the cylinder charge, substantially as and
for the purposes herein sot forth.
Second. In a twin gas motor engine of the kind referred to in the precoding
claim, the arrangement of ports and passages in combination with a single slide so
moved as to alternate the action of the two cylinders, substantially as horein
described.
Third. The construction of twin gas motor engines substantially as herein
described and shewn by the accompanying drawings.
In Witness whereof I the said Francis William Crossley have hereunto set my
hand and seal this fifteenth day of December in the year of our Lord One
thousand eight hundred and eighty three.
FW CROSSLEY (1.s)