GAS MOTOR ENGINE
Year: 1884

page_text: I, HENRY PERCY HOLT, of Openshaw, Manchester, in the County of Lancaster
Engineer, do hereby declare the nature of my invention for "GAS MOTOR ENGINE"
to be as follows:-
This invention relates to a construction of gas motor engine, in which the
passages for charging, igniting and exhausting are governed by the movements of
the piston, without requiring a separate slide."
The exhaust is so arranged that, towards the end of the outstroke of the piston,
the pressure in the cylinder is below that of the atmosphere. At this time, as the
piston is approaching the end of its outstroke, a port in the piston is brought
opposite to a port in the side of the cylinder communicating with the air and gas
supply, and a charge of gas and air is drawn into an open mouthed cavity in the
piston. As the piston makes its instroke, it closes the charging port, but an
exhaust passage opening outwards from the piston then for a time faces a port in
the side of the cylinder communicating by a longitudinal passage with the farther
end of the cylinder, and by this passage a portion of the gaseous products of
previous combustion is expelled as exhaust. The piston, continuing its instroke,
closes this exhaust port and then goes on compressing the contents of the cylinder,
consisting of the air and gas in the cavity of the piston, and of the residuary
products of combustion beyond the piston. At the end of the instroke, a port in
the piston faces an igniting port in the side of the cylinder and the charge is
ignited by contact with any known igniter. The increase of pressure and volume
resulting from the combustion of the charge propels the piston. The piston, in its
outstroke, first uncovers the exhaust port allowing a portion of the products of
combustion to escape, and then closes it, so that, a little before the end of the
outstroke is attained, the pressure is sufficiently reduced to effect the drawing in of
the fresh charge as above described. The gas supply is determined by a valve
regulated by a governor in a manner such as has been adopted in the Otto gas
motor engines.

page_text: "2
I, HENRY PERCY HOLT, of Openshaw, Manchester in the County of Lancaster,
Engineer, do hereby declare the nature of my invention for "GAS MOTOR ENGINE
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 a construction of gas motor engine in which the
passages for charging, igniting and exhausting are governed by the movements of
the piston, without requiring a separate slide, as I will describe referring to the
accompanying drawings. Fig. 1 is a longitudinal section of the cylinder shewing
the piston P at the extreme of its instroke, the dotted line p indicating the position
of the front edge of the piston at the extreme of its outstroke. Through the side
of the cylinder there are ports, A for admission of the combustible mixture, B for
discharge of exhaust, and C communicating with the igniter. There is also a
passage D extending back to the rear end of the cylinder. The piston P is made
with a cavity E having a lateral passage F, and it has also a recess G which at one
part of the stroke makes communication between D and B. The action is as
follows: Towards the end of the outstroke of the piston P, the pressure in the
cylinder behind it is below that of the atmosphere; the passage F then facing A, a
charge of combustible mixture is drawn into the cavity E. As P makes its
instroke, it closes A, but while G passes B and D a portion of the products of
previous combustion is expelled. After G has passed B and D, the piston continues
its instroke compressing the contents of the cylinder, consisting of the combustible
charge which is mostly in the cavity E and passage F and of such portion of the
products of previous combustion as had not been expelled at B.
When F faces the igniting passage C, the compressed charge. in F and E is
ignited, and the increase of pressure and volume resulting from the combustion of
the charge propels the piston. During the outstroke of the piston, as G passes D
and B, a portion of the products of combustion is allowed to escape, then G having
passed still farther outwards so that B and D are closed, the residue of the contents
of the cylinder become somewhat rarefied, so that, when F faces A, a fresh charge
is drawn in, and the action is repeated.
Fig. 2 shews a somewhat modified arrangement, where the chamber E is not
within the body of the piston P, and where the communication to the outlet
exhaust B is made by extending G to the rear end of the piston.
When it is desired that there should be no escape of products by the port B
as the piston makes its return stroke inwards, a spring valve may be applied
to B this spring being adjusted so that the valve will not open except when
there is a pressure within the cylinder exceeding that of the atmosphere by several
pounds.
I have shewn a single inlet A for gas and air, the gas supply being regulated in
the usual way,

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
The construction of gas motor engine having passages for charging, igniting and
exhausting governed by the movements of the piston, substantially as herein
described.