Year: 1888

page_text: I, JOSEPH SOUTHALL, of the Firm of Hardy and Padmore, of Worcester Foundry,
in the County of Worcester, Engineer, do hereby declaro 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 :-
My invention relates to gas motor engines of the kind described in my Specifications
No. 12424 of 1885 and No. 15472 of 1886.
In a gas motor engine according to my present invention, I employ two equal
cylinders each closed at both ends placed horizontally side by side and having their
piston rods passing through stuffing boxes and linked to the same crank on a crank
shaft. The cylinders have ports and passages governed by valves for the admission of
gaseous mixture, and the discharge of products of combustion, to and from each of
their four spaces that is to say the spaces on both sides of the two pistons. These
valves are so operated that the four strokes constituting a complete cycle, one for
drawing in the charge. one for compressing the charge, one for propelling by the
firing of the charge, and one for expelling products of combustion, are performed
successively in each of the four spaces these four operations being so timed that at
each stroke, a different operation goes on in each of the four spaces simultaneously,
the action of the engine being thus to a large extent equalized.
The two front spaces communicate by passages governed by valves worked by the
engine, with a reservoir, and the two hinder spaces communicate in like manner with
another reservoir, and the valves are so timed that during the first part of a stroke,
while one piston is compressing the charge of gaseous mixture behind it and the other
is expelling products of combustion, a portion of the charge undergoing compression
is forced into one of the reservoirs and is there retained till the pistons have reached
the ends of their strokes. A valve is then opened, allowing compressed fluid from the
reservoir to rush into the space whence products of combustion have just been
expelled, driving out residue of these, and taking their place as part of the next
charge. By these arrangements each of the four spaces is in its turn cleared of
products of combustion, and is charged with combustible mixture which is not vitiated
to any appreciable extent by admixture of residue from previous combustion.
I will describe a gas motor engine according to my invention referring to the
accompanying drawings. Figs. 1 and 2 are respectively a side elevation and a plan
of the engine, the cover of the valve box in Fig. 2 being removed. Fig. 3 is an

page_text: enlarged horizontal section of the cylinders, shewing the gas and air inlet valves.
Fig. 4 is a vertical longitudinal section through one of the cylinders, the upper and
under valve chambers and the reservoirs. Fig. 5 is a transverso section through
both cylinders and one of the gas and air inlet valves with the reservoir and passages
leading therefrom. Fig. 6 is a sectional plan of the upper valve chamber, a similar
section applying to the lower valve chamber. Fig. 7 is an enlarged part section about
midway in the length of a cylinder shewing arrangements for regulating the engine by
a governor and for lubricating the piston. Fig. 8 is a plan partly in section shewing
an arrangement for igniting the charge. Similar reference letters and numerals are
used in the several figures to indicate corresponding parts.
The two horizontal cylinders M³ M² are placed near together side by side. They
have, as usual water casings W, and their pistons P P are connected to one crank P
on the flywheel shaft S which by suitable skew gear within a casing G drives the
counter shaft A at half the speed of S.
When the pistons P¹ P' are in the positions shewn in Fig. 3, that is to say at
the extreme ends of their instroke, the space C contains the combustible charge,
and the space 2 contains products of previous combustion. As the piston P" performs
the first part of its outstroke it forces a portion of the combustible charge from C
by the passages 10 and 11, the valve V₁ being then open, into the reservoir 12, where-
upon the spring valve V' is closed. The piston Pl advancing to the end of its out-
stroke, compresses the remaining portion of the charge in the space C. During the
same outstroke the exhaust valve L being open, the piston P2 drives out products of
combustion from the space C to the exhaust pipe E. The valve V governing the
passage from the reservoir 12 to the space C being now opened, combustible mixture
from the reservoir 12 rushes into the space, expelling the remaining products of
combustion, and itself forming a portion of the next charge of C. The exhaust
valve of being now closed, the compressed charge in C is ignited and the
pistons are propelled inwards. During the instroke of the piston P it draws in a
fresh charge of air through the valve FI along with gas issuing from a number of holes
in the valve seat leading from an annular chamber 16 supplied with gas. The mixed
charge enters the reservoir 12 and passes to the space C, the valve V2 being then
open. The operations described in respect of the spaces 0 and 2 are repeated
inversely in respect of C2 and C³, and similarly in respect of C3 and CC, and thus
the four strokes of the cycle for drawing in the charge, compressing the charge,
firing the charge and expelling products of combustion are performed successively in
each of the four spaces 0, 0, 0, 0, each of these four operations taking place, one
in one of the spaces, another in another of the spaces, and so on, simultaneously so
that there are two propelling strokes in each revolution of the crank.
The four exhaust valves L L L L one for each of the spaces C1 C2 C3 C¹¹ are
situated in a casing K under the cylinders and the valves V1 V2 V3 V4 are in a
casing N above the cylinders. The eight valves L' L² L³ and L^, V1 V2 V³ and V4
are worked as shewn from four eccentrics on the shaft A, each eccentric working two
of the valves.
As shewn in Fig. 6, there are in cach of the casings K and N two three armed
levers 8 and 9, each having one of its arms worked by a transversely sliding rod B.
The other arms act on the stems of the spring valves opening thom alternately.
Two of the eccentrics on the shaft A are linked directly to the sliding rods B of
the lower casing K, and the other two eccentrics work through bell cranks B₁ the
sliding rods B of the upper casing N.
The arrangement for lubricating the pistons is shewn in Fig. 7. A tube 3 leading
into each cylinder is fitted with a spring valve 4 having oil passages bored in it. The
lubricant is supplied from a chamber 5 in quantity regulated by a screw plug 1, so
as to drop into a cup on the stem of the valve 4. An arm 2 projecting from one of
the levers 8 or 9 has at its end an incline, which bearing on the top of the stem
of the valve 4 at each stroke, pushes the valve down, and allows a little lubricant
to flow into the cylinder this action being timed so as to take place during the exhaust
stroke.

page_text: For igniting the charges in the four cylinder spaces, any known suitable igniting
apparatus may be employed. In Fig. 8 I shew a convenient arrangement as applied
to the two back spaces CC, it being understood that a like arrangement is applied to
the corresponding front spaces C¹ C. Each of the three armed levers 8 and 9 works.
another three armed lever I which alternately opens the spring valves governing small
passages such as from the cylinder spaces, making communication from these
respectively to a heated tube T.
The regulation of the speed of the engine may be effected by a governor applied as
shewn in Fig. 7. An ordinary centrifugal governor Q as its speed varies moves a
lever causing an arm R to swing to and fro horizontally, this arm being suspended
from one end of a lever Z and having on it stops projecting under the arm of each
of the bell cranks B' which arm has on it projections bb. The other arm of Z is
linked to a sliding bush X fitted in a slot of each of the rods B.
While the speed of the engine is normal, the upper end of the bell crank B¹ being
engaged within the bush X gives the rod B its full stroke, but when the speed of the
engine becomes too great, the arm R is moved outwards by the governor so that its
lower stop comes under the lower projection and the bell crank arm B₁ then pushes
down the arm R thereby causing the bush X to move upwards, so that the upper arm
of the bell crank B¹ fails to move the rod B, and therefore does not open the valve
by which the charge is supplied to the cylinder. When the speed of the engine is
thus reduced, the upper stop is acted on by the upper projection b so as to bring the
bush X back to its normal position.
Although in what precedes I have described both pistons connected to a single
crank, they might obviously be connected to cranks opposite to one another, the valvo
gear being suitably arranged to time the valves to the described cycle of operation.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a gas motor engine having two double acting cylinders and having valve
gear so timed that during each half revolution of the crank shaft, one of the four
cylinder spaces receives charge, in one the charge is compressed, in one it is fired,
and from another products of combustion are expelled, providing reservoirs and
passages so controlled by valves that part of each compressed charge is forced into one
of the reservoirs, and that a portion of the contents of this reservoir passes into the
space which is under exhaustion to expel therefrom residue of products of combustion,
substantially as described.
2. In a gas motor engine operating in the manner referred to in the preceding
claim, in combination with a shaft driven at half the speed of the crank shaft, the
four eccentrics with the rods and levers connected therewith for working the four_
reservoir valves and the four exhaust valves, substantially as described and illustrated
by the drawings.
3. In a gas motor engine of the kind above referred to, the appliance for lubrication
of the cylinders herein described with reference to Fig. 7.
4. In a gas motor engine of the kind above referred to, the governing apparatus
herein described with reference to Fig. 7.
Dated this 30th day of May 1888.
ABEL & IMRAY,
Agents for the Applicant.