A Double Acting Gas Engine.
Year: 1896

page_text: Date of Application, 24th Feb., 1896-Accepted, 4th Apr., 1896
A Double Acting Gas Engine.
I, SAMUEL SIDNEY BROMHEAD of 97 Newgate Street London, Patent Agent, (a
communication) 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 refers to an improved gas engine, which will work equally well
with ordinary lighting gas, or with gas deficient in carbon, or with any mixture of
air and carburetted hydrogen.
The explosion cylinder is closed at each end similarly to the cylinders of steam
engines, and the piston receives alternately at every two revolutions, an explosion
at each of its two faces.
When
The admission of the explosive mixture occurs only at one end of the cylinder,
and lasts during the whole stroke of the piston; but on the return of the piston the
two ends of the cylinder, being put in communication, part of the mixture is
driven back from one end of the cylinder and drawn into the other end.
the mixture is thus divided into two nearly equal parts, the communication is
interrupted. Then the piston continuing its course compresses the first portion of
the mixture as far as the dead point where the ignition occurs. The piston then
driven by the explosion performs its work, by the expansion of the heated gas,
which extends to double its original volume, and at the fourth motion of the piston
the gasses are expelled.
During the third motion and whilst the expansion of the first portion is taking
place, the second portion is similarly compressed, and then ignited at the dead
point, after which it expands and finally is expelled as before stated.
The regulating control is obtained by the action of the governor, either by
modifying the richness of the explosive mixture or by suppressing the flow of gas
altogether.
I will now describe the invention with reference to the accompanying drawings,
in which
Fig. 1 shows a longitudinal elevation partly in section.
Fig. 2 shows an end elevation and partial cross section.
The same letters denote the same parts in both figures.
The motor is composed of a cylinder A in which the piston B works, the rod of
which is connected to a crank and axle not shown.
The admission of the explosive mixture is provided for thus; the air enters by
the valve D, and the gas by the valve E.
The outlet for the spent gas takes place by the valves G, the first portion escaping
by the valve in the chamber H and the second by that in the case I.
The communication between the two ends of the cylinder, takes place by means
of the valves F and J and the passage connecting their chambers.
The inlet valve D is actuated by the lever K partly shown, which receives its
motion from a cam not shown, mounted on the axle L arranged to make one
revolution while the crank axle makes two.
This lever K carries at M a tappet which in its rising movement and during the
opening of the valve D, meets the arm N of the angular lever N, O, and thus opens
the gas valve E, to which it is attached.

page_text: Analogous levers and cams to K and its cam actuate at the time required the
valves F, J. Two levers P and two cams Q operate also in due time the outlet
valves G of the chambers H and I.
The centrifugal governor R when the speed of the motor is excessive, raises the
rod S, which by the nuts T fixed thereto lifts the arm O of the lever of the gas
valve and disengages the arm N of the tappet M of the lever K thus leaving the
air valve D only open.
But before the lever N has travelled its entire course
which disengages it from the tappet M, the rod S of the regulator operates at V
a lever VX, shown in dotted lines in Fig. 1, moving at X a valve which diminishes
the orifice by which the gas enters, and thus decreases the richness and effective
force of the explosive mixture, and it is at the limit of the weakness of this
mixture that the nuts T of the rod S commence to act upon the lever N, O, and
suppress the admission of gas.
The ignition of the explosive, mixture, is produced by the inbe Y heated to a
red heat by an ordinary blow pipe. This tube is placed in communication at the
proper time with the interior of the cylinder by the opening of the small valve Z,
operated by a lever and cam mounted on the axle L." The exhaust pipe of the
valve in the chamber I, communicates with passage to the exterior formed for the
expulsion of the spent gas by means of the pipe I, at about the centre of which
there also terminates the tube H' from the exhaust valve in chamber H. When
the exhaust in chamber I is on the point of terminating that in His commencing,
and its action causes by its strong pressure a suction at its mouth in the tube I",
and consequently in that part of the cylinder where the explosive mixture is required
to enter.
At this moment only the air valve D, being open, the partial vacuum created in
the cylinder creates a need of air which continues to flow in up to the moment when
the valve in the chamber I, closes in order to replace the products of combustion
expelled by the suction in the pipe I¹. It results from this that the explosive
mixture drawn in being composed almost entirely of pure air and gas to the exclusion
of the consumed products it will thus have its combustion facilitated and will
augment the power and action of the motor.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is
1. In a gas engine the arrangement of a cylinder closed at both ends so that
while admitting the explosive mixture on one side of the piston two explosions are
obtained by distributing the mixture in two nearly equal parts, one on each side of
the piston, thereby increasing the force of the motor by the prolonged expansion of
the burnt gas, which expands to about double its primitive volume, as herein described
and set forth.
2. In a gas engine the arrangement whereby the action of the governor diminishes
in case of excessive speed the force of the explosive mixture, by the partial
suppression of the supply of gas, and is further enabled to shut off the gas
altogether, as herein described and set forth.
3. In a gas engine the arrangement of the exhaust pipes in the form of an ejector,
so disposed that the second exhaust produces a suction in the passage of the first
and also in the part of the cylinder where the explosive charge is required, ensuring
at the same time a mixture of pure air and gas almost entirely free from the products
of combustion of the preceding charge, as herein described and set forth.
Dated this 24th day of February 1896.
S. S. BROMHEAD,
97 Newgate Street, London, Patent Agent.