Improvements in Gas or Internal Combustion Engines.
Year: 1893

page_text: Date of Application, 1st Dec., 1893
Complete Specification Left, 1st Sept., 1894-Accepted, 6th Oct., 1894
PROVISIONAL SPECIFICATION.
Improvements in Gas or Internal Combustion Engines.
We, FRANCIS WILLIAM CROSSLEY of Crossley Brothers, Limited, Openshaw,
Manchester, Engineer, and JAMES ATKINSON of Amherst, Fallowfield, Manchester,
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to the valve gear of gas or other internal combustion
engines working on what is known as the "Otto" cycle, and its object is to operate
the necessary valves in an improved manner, preferably directly from the crank-
shaft, instead of from a sideshaft driven by gearing at half the speed of the engine
as is now commonly done.
It also relates to means for keeping the exhaust valve cool.
The valves necessary to an engine of this type are the charging valve, the gas
valve, and the exhaust valve; and our invention is for the purpose of satisfactorily
controlling these by means of one or more. eccentrics, or cams, which make a
complete movement once for every revolution though the engine requires two
revolutions to complete its cycle.
With respect to the charging valve, this may be allowed to be sucked open by
the outward movement of the piston during a suction or charging stroke, and as
the gas valve is shut off from the cylinder by the charging valve, it may be
opened every revolution without disadvantage so long as working strokes are to be
niade.
The exhaust valve, which is operated by an eccentric, must not be opened at
each revolution, being always left closed on the inward or compression stroke
following a suction stroke, during which suction stroke a combustible mixture has
been drawn in, and for the purpose of preventing the opening of the exhaust valve
at improper times we provide a connection operated preferably by the stem of the
charging valve, which acts upon a catch or distance piece in such a manner that
each time the charging valve is opened the catch or distance piece is moved aside,
80 that the eccentric which operates the exhaust valve does not open it at the
following stroke.
If only one eccentric is used for opening both exhaust, gas valve, & charging
valve, the motion which operates the exhaust valve may be taken off from the
eccentric at a different angle from that which operates the gas & charging valves,
so that each may thus be suitably timed.
Any suitable governor may govern the engine by deciding whether the gas valve
shall be opened during charging strokes, or miss opening it when the engine runs
too fast. When the gas valve is not opened the piston of the engine may be
allowed to draw air only into the cylinder, to be compressed, re-expanded, and
then exhausted. Otherwise, by another arrangement, when the gas valve is not
opened the same gear may be so adjusted by the governor that the charging
valve is opened mechanically instead of the gas valve, at about the commencement
of the charging stroke, and kept open for almost a complete revolution; in this
case, on the return stroke,-which would in the other arrangement be a com-
pression stroke, the air is driven back into the air pipe or chamber from which it
was drawn; the charging valve having been opened the exhaust valve is not
operated, and the engine thus continues drawing in and expelling air until the
governor deciding that a working stroke is required to keep up the speed opens the
gas valve instead of the charging valve.
The latter arrangement has the advantage of allowing a working stroke to follow
an idle stroke a revolution earlier than it might by the other arrangement or than

page_text: in the case of engines as usually constructed with the valves operated in a cycle of
two revolutions.
There may be an additional valve in the gas pipe to prevent gas passing into the
air pipe when the gas valve moved by the governor is open, but while suction is
not taking place.
In oil or vapour engines the oil or vapour valve takes the place of the gas valve,
and is operated in the same manner.
The exhaust valve in gas or oil engines being usually of the mushroom type
frequently gets very hot in working, and, especially in large engines, is sometimes
so hot as to fire the charge prematurely. To prevent this we arrange that its head
moves in a cavity which protects it from direct contact with the rapidly moving
hot gases during exhaust and partly also from the heat during the working stroke.
The metal forming the cavity may be water jacketed. This improvement may be
applied to any gas or oil engines in which such exhaust valve is employed.
Dated this 30th day of November 1893.
COMPLETE
SPECIFICATION.
Improvements in Gas or Internal Combustion Engines.
We, FRANCIS WILLIAM CROSSLEY, of Crossley Brothers Limited, Openshaw,
Manchester, Engineer, and JAMES ATKINSON of Amherst, Fallowfield, Manchester,
Engineer, 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 :-
This invention relates to the valve gear of gas or other internal combustion
⚫ engines working on what is known as the "Otto" cycle, and its object is to operate
the necessary valves in an improved manner, preferably direct from the crank
: shaft, instead of a side-shaft driven by gearing at half the speed of the engine as
is now commonly done.
It also relates to means for keeping the exhaust valve cool.
To enable our invention to be clearly understood we append drawings of an
engine constructed with our improvements in which
"
Fig. 1 is an end elevation, Fig. 2 a plan partly in section, Fig. 3 an end
elevation, Fig. 4 an elevation of one side and Fig. 5 an elevation of the other
side partly in section.
In these views like letters apply to like parts.
The usual valves in an engine of this type are the charging valve B, the gas
valve F, and the exhaust valve C. Our invention is for the purpose of satisfactorily
controlling these by one or more excentrics, or cams, (the arrangement shewn in
the drawings is by means of two excentrics) which make a complete movement once
for every revolution though the engine requires two revolutions to complete its
cycle.
With respect to the charging valve B this may be allowed to be sucked open by
the outward movement of the piston G during a suction or charging stroke and as
the gas valve F is shut off from the cylinder by the charging valve B it may be
opened every revolution without disadvantage so long as working strokes are to be
made it being understood that a suitable regulating arrangement is applied to the
gas supply which prevents the gas being at any material pressure above atmospheric
pressure.
The exhaust valve C, which is operated by the excentric R, must not be opened
at each revolution, being always leit closed on the inward or compression stroke
following a suction stroke during which suction stroke a combustible mixture has
been drawn in and for the purpose of preventing the opening of the exhaust valve C

page_text: at improper times we provide a connection preferably operated by the stem of the
charging valve B, which acts upon a catch or distance piece T in such a manner
that each time the charging valve B is opened, the lever M operating through the
shaft N, lever and distance piece S, moves the catch T aside, so that the
'excentric R which operates the exhaust valve C does not open it at the following
stroke.
If only one excentric is used for opening both exhaust valve C, gas valve F and
charging valve B, the motion which operates the exhaust valve C may be taken off
from the excentric at a different angle from that which operates the gas valve' F,
and charging valve B, so that each inay thus be suitably timed.
Any suitable governor may govern the engine (in the drawings an inertia.
governor is shown) by deciding whether the gas valve shall be opened during
charging strokes, or miss opening it when the engine would otherwise run too fast.
When the gas valve F is not opened the piston G of the engine may be allowed to
draw air only into the cylinder, to be compressed, reexpanded, and then exhausted.
Otherwise, by another arrangement (and this is the arrangement shewn in the
drawings,) when working strokes are not to be made the gas valve F is not opened
by the striker P of the governor Q, but this striker P being thrown upwards by
the action of the governor at the reversal of the motion at the end of the stroke
into the position shewn in Fig. 5 opens the charging valve B mechanically, instead
of the gas valve F, at about the commencement of the suction stroke. When thus
opened the charging valve B is kept open during almost the whole of a complete
revolution of the engine, so that on the return inward stroke no compression takes
place, the air previously drawn in is driven back through the valve B into the air
pipe or chamber from which it was drawn. The charging valve B having been
opened the exhaust valve C is not operated. The engine thus continues drawing
in and expelling air until the governor Q deciding that a working stroke is required
to keep up the speed; the striker P is allowed to open the gas valve F, instead of
the charging valve B, in which case the suction of the piston automatically opens
the charging valve B, draws in an explosive charge which is compressed on the
return inward stroke, ignited so as to give a working pressure on the outward power
stroke, and then exhausted by the following inward stroke, the exhaust valve C
being opened because the charging valve B was not opened on the previous power
stroke as previously explained. Power strokes will be given at each second
revolution so long as the striker P opens the gas valve F but idle revolutions only
when the charging valve B is opened instead.
The latter arrangement has the advantage of allowing a power stroke to follow
an idle stroke a revolution earlier than it might by the other arrangement, or than
in the case of engines as usually constructed with the valves operated in a cycle of
two revolutions.
There may be an additional valve in the gas pipe to prevent gas passing into the
air pipe when the gas valve F is open but while suction is not taking place. This
valve may be a lightly loaded self-acting valve.
In oil or vapour engines the oil or vapour valve takes the place of the gas valve F
and is operated in the same manner.
The exhaust valve C being usually of the mushroom type frequently gets very
hot in working, and, especially in large engines is sometimes so hot as to fire the
charge prematurely. To prevent this we arrange that its head, or a substantial
projection on its head, as shewn moves in a cavity which protects it from direct
contact with the rapidly moving hot gases during exhaust and partly also from the
heat during the working stroke. As shewn in Fig. 2 the cavity in which the
valve head moves is constructed in the cover to the valve and is water jacketted.
The large projection being cooled by contact with water jacketted metal cools the
valve head by conduction. In extreme cases it may be necessary to make the
projection as large in diameter as the valve head itself, but in most instances a
smaller projection as shewn will be sufficient. This improvement may be applied
to any gas or oil engine in which such an exhaust valve is employed.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. In a gas or internal combustion engine the operation of the exhaust valve C
and the charging valve B by means of one or two excentrics or cams in such a
manner that the opening of the charging valve B during a suction stroke by means
of suitable mechanical connections prevents the exhaust valve C from being opened
during the next following return stroke as and for the purpose described and
illustrated.
2. In a gas or internal combustion engine so constructed that the opening of the
charging valve B during a suction stroke prevents the opening of the exhaust
valve C during the next following exhaust stroke, the arrangement whereby the
governor opens either the charging valve B to give idle revolutions or the gas
valve F to give working revolutions, as described and illustrated.
3. The general arrangement of gas or other internal combustion engines as
described and illustrated:
Dated this 31st day of August 1894.