Improvements in or relating to Gas or Vapour Engines.
Year: 1894

page_text: Date of Application, 11th May, 1894
Yomplete Specification Left, 11th Feb., 1895-Accepted, 16th Mar., 1895
PROVISIONAL SPECIFICATION.
Improvements in or relating to Gas or Vapour Engines.
I, WILLIAM DICKINSON of Park House, Sunderland in the County of
Durham, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention has reference to improvements in or relating to gas or vapour
engines and has for its object the design and construction of a double acting
engine of this class that is to say a gas or vapour engine having or capable of
having a cycle of operations analogous to an ordinary high pressure steam engine
with two impulses per revolution.
To effect my purpose I arrange in connection with the motor cylinder gas and
air pumps adapted to compress these fluids to any required ratio of pressures and I
further construct the piston of the motor cylinder of a length approximately
equal to the stroke minus the width of the air port afterwards described.
I further arrange a central air port or ports and terminal exhaust ports to the
motor cylinder and gas ports may likewise be arranged in suitable positions
towards either end of the motor cylinder so that on the piston travelling in one
direction it shall finally uncover the central air port or ports and a scavenging
charge under pressure from the air pump entering thereat behind the piston shall
drive out the products of combustion through the exhaust and on the return of the
piston at a certain point the exhaust valve closes and a portion of the scavenging
charge behind the products of combustion is trapped or retained into which gas
or a mixture of gas and air is forced by a pump the whole mixture being then
further compressed by the motor piston until ignition whether by light flame hot
tube or spark or other suitable means takes place to again drive out the piston.
It will be observed that the piston acts as a valve to the central air port which
delivers its scavenging charge at a pressure alternately in reverse directions to the
exhaust at the opposite ends of the cylinder and the precise timing of the various
openings and closings of the exhaust gas admission and other valves will be set to
suit the particular conditions or requirements of the case.
In all other general particulars the engine may resemble ordinary practice and
where gas is named as being used the vapour or spray of oil is intended to be
included in that terin.
All ordinary details of construction not herein specially alluded to may be of
any ordinary and approved type.
Dated this 10th day of May 1894

page_text: improvements in or relating to Gas or vapour Engines.
I, WILLIAM DICKINSON, of Park House, Sunderland in the County of
Durham, 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 has reference to improvements in or relating to gas or vapour
engines and has for its object the design and construction of a double acting
engine of this class that is to say a gas or vapour engine having or capable of
having a cycle of operations adapted to produce two impulses per revolution.
To effect my purpose I arrange in connection with the motor cylinder gas and
air pumps adapted to compress these fluids to any required ratio of pressures and
I further construct the piston of the motor cylinder of a length approximately
equal to the stroke minus the width of the air port device afterwards described.
I further arrange a central air port or ports and terminal exhaust ports to the
motor cylinder and gas ports may likewise be arranged in suitable positions towards
either end of the motor cylinder so that on the piston travelling in one direction
it shall finally uncover the central air port or ports and a scavenging charge under
pressure from the air pump entering thereat behind the piston shall drive out the
products of combustion through the exhaust port and on the return of the pistou
at a certain point the exhaust valve closes and a portion of the scavenging charge
behind the products of combustion is trapped or retained into which gas or a
mixture of gas and air is forced the whole mixture being then further compressed
by the motor piston until ignition whether by light flame hot tube or spark or other
suitable means takes place to again drive out the piston.
It will be observed that the piston acts as a valve to the central air port
which delivers its scavenging charge at a pressure alternately in reverse directions
to the exhaust at the opposite ends of the cylinder and the precise timing of the
various openings and closings of the exhaust, gas admission and other valves will
be set to suit the particular conditions or requirements of the case.
In all other general particulars the engine may resemble ordinary practice and
where gas is named as being used the vapour or spray of oil is intended to be
included in that term.
All ordinary details of construction not herein specially alluded to may be of
any ordinary and approved type.
I will fully describe my invention with reference to the accompanying drawings
in which Figure 1 shows a longitudinal vertical section, Figure 2 a sectional plan and
Figure 3 a transverse section of machinery showing how I carry my invention
into practical effect and in the following description like marks of reference
designate like parts.
Referring to the drawings M is the motor cylinder, A the air pump cylinder
and G the gas pump cylinder.
The connecting rods from these three cylinders may be coupled to the crank
shaft in any convenient manner.
The valves in connection with the gas and air pump cylinders may likewise be
arranged in any convenient manner that is to say there will obviously be required
suction and delivery valves at each end of these cylinders and their exact position
or design is immaterial to my invention.
The motor cylinder must have at its central point an air-inlet port or ports A.
Four of such ports are shown in the drawings.
Gas-inlet ports V V₁ may be provided as shown to the motor cylinder whose
exhaust ports E E' will be at opposite ends of the cylinder.

page_text: The piston P of the motor cylinder must be constructed of a length equal or
approximately equal to the length of the stroke minus the width of the central air
port or ports aforesaid as shown in the drawings.
A cycle of operations may thus be as follows:
Assuming the piston of the motor cylinder to be at the extreme left-hand end
of the cylinder the exhaust valve E¹ will be open and the air-ports A will have
been uncovered by the piston and air compressed by pump A will rush from air-
storage chamber C into the cylinder to drive out the products of combustion of
the previous stroke through the right-hand exhaust port E¹. As the piston
advances from left to right it gradually covers and closes the air-ports and at a
certain point in its stroke the exhaust port E¹ is closed and immediately there-
after the gas-inlet valve at V₁ will be opened to allow gas to enter the motor
cylinder and mix with the air which had entered through ports A. The gas and
air will then be compressed by the advancing piston in the right-hand end of the
cylinder and at the required moment the mixture will be fired in any convenient
manner as above described to again actuate the piston; when however the piston
has advanced sufficiently far towards the right-hand end of the cylinder, its
opposite or left-hand end will have again uncovered the medial air-ports A,
through which air will again rush in the contrary direction to drive out the
products of combustion from the opposite end of the cylinder through exhaust
port E and the piston returning to the left the operations already described will
be repeated at the left-hand side of the piston.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A double acting gas or vapour engine having two impulses per revolution
consisting of a motor cylinder with air and gas pump cylinders, the motor cylinder
having central air ports adapted to be alternately covered and uncovered by the
reciprocating piston which is constructed of a length approximately equal to the
length of the stroke minus the width of the medial air port the parts being
arranged to effect a cycle of operations substantially in the manner and for the
purposes herein set forth.
2. The combination of parts forming a double acting gas or vapour engine,
arranged, constructed, and adapted to work substantially as herein set forth.
Dated this 9th day of February 1895.
A. CRAWHALL CHAPMAN,
3, St. Nicholas Buildings, Newcastle-on-Tyne, Patent Agent.