IMPROVEMENTS IN GAS ENGINES
Year: 1884

page_text: I JOHN EDWARD ROGERS of Poplar Street Smethwick in the County of Stafford
Machinist, do hereby declare the nature of my invention for IMPROVEMENTS IN
GAS ENGINES to be as follows:-
On a Bed Plate similar in design to those used in an ordinary Horizontal Steam
Engine with Bearings to receive the Crank Shaft, which Crank Shaft according
to my Invention would be double Cranked and set at opposite ends of their
Strokes, so, that when one Crank had completed it outward Stroke, the other one
would have completed its inward Stroke; each of theso Cranks would have its
distinct Connecting Rod, Piston and Cylinder.
The Pistons according to my Invention would be of the design known as the
Trunk Piston and of the same diameter the whole of their length and their length
for the purpose of carrying out my Invention would exceed the stroke of the
Engine.
The Cylinders would have an outer or Water Caseing.
The design of Engine according to my Invention, that I am now describing
would consist of two distinct Cylinders with their Trunk Pistons, Connecting
Rods, and Cranks set in the positions before mentioned, viz, at the opposite ends
of their stroke. On one of the Cylinders the Slide Valve works for distributing
and igniting the Gases motion being given to it from an eccentric fixed on the
Crank Shaft, and all mounted on a suitable Bed-Plate.
The design of my Invention being understood to explain the working of the
same I shall hereafter describe one Cylinder as the Cold Cylinder and the other as
the Hot Cylinder.
The Cold Cylinder Piston having been brought to the end of its stroke outwardly
it has uncovered passages through the Cylinder for the admission into it of the
required proportions of Gas and Air to form the explosive mixture used in working
the Engine. The Cold Cylinder Piston then returns to the inward end of its
stroke and compresses the mixture taken in at the outward end of its stroke by
which time the Slide Valve that works on the Hot Cylinder has opened communi-
cation between the two Cylinders through a passage fitted with a Back Pressure
Valve acting as an auxilliary to the Slide Valve and against the Cold Cylinder,
that is the explosive mixture has a free passage from the Cold to the Hot Cylinder
but cannot return.

page_text: When the Slide Valve is in a position for admitting the compressed explosive
mixture from the Cold to the Hot Cylinder the Hot Cylinder Piston would be at
the outward end of its stroke and in an opposite position to the Cold Cylinder
Piston, and would have uncovered passages through the Hot Cylinder communi-
cating with the atmosphere for the purpose of exhausting the Hot Cylinder.
The position of the parts of the Engine being as stated the compressed explosive
mixture in the Cold Cylinder would pass into the Hot Cylinder and expand, this
expanding of the Gases would have a beneficial influence in the working of the
Engine by absorbing a portion of the heat caused by the explosions in the Hot
Cylinder.
(1.f
1.1.14
The Hot Cylinder Piston then commences to return to the back end of its
Cylinder, and again compresses the charge of explosivo mixture that it has received
from the Cold Cylinder, and when the explosive mixture is under pressure in
the Hot Cylinder the Slide Valve has been brought with its ignition port in
communication with the explosive mixture in the Hot Cylinder and explodes it,
thus giving motion to the Engine and the same round of charging compressing,
expanding, again compressing and exploding is repeated in the working of an
Engine constructed according to my Invention.
This design of Engine may be varied without departing from the nature of my
Invention.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same be performed I declare what I claim is
1 The use in a Gas Engine of the method of taking up the explosive mixture for
working the same that is to say the taking up of the explosive mixture through a
Port or Ports uncovered by the Piston in its stroke either way substantially as
shewn and described (see Ports H and L Figure (3).
2 The taking up of the explosive mixture through air Valve G in combination
with Gas Port H substantially as shewn and described.
Dated this 25th day of February 1885,
JOHN EDWARD ROGERS,
Poplar Street, Smethwick,
County of Stafford,
Machinist.