Improvements in Gas Motors.
Year: 1889

page_text: Date of Application, 4th Feb., 1889
.Complete Specification Left, 2nd Nov., 1889-Accepted, 7th Dec., 1889
Improvements in Gas Motors.
I, DAVID BRUCE PEEBLES, of Tay Works, Bonnington, Edinburgh, in the County
of Mid Lothian, North Britain, Engineer, do hereby declare the nature of this Inven-
tion to be as follows, that is to say :-
My said Invention has for its object to improve the construction and operation of
gas motors.
In carrying out Invention according to one modification I employ a long double-
acting plunger or piston the ends of which work in cylinders at the opposite ends of
a casting which may be internally a continuous cylinder from ond to end but which
has at its middle part a slot having projecting through it a strong stud fixed to the
middle of the plunger. I prefer to place the cylinder horizontally with the plunger
stud projecting up through the slot made in the upper side of the cylinder.
The plunger is, by means of its stud and a connecting rod, made to act on a crank
shaft placed with its axis at a level higher than the cylinder so that when the crank
is in its lowest position the connecting rod extends nearly horizontally just above the
cylinder. A mixture of air and gas is exploded twice at equal intervals during
every three revolutions of the crank shaft, once in each end of the cylinder; and
the cycle of operations at one end or cylinder is as follows,-1, outstroke taking in
gas and air, 2, instroke compressing, 3, outstroke exploding, 4, instroke expelling
products, 5, outstroke drawing in air to clear cylinder, and 6, instroke expelling
clearing air. When the explosion is taking place at one end the clearing air is being
expelled at the other end.
The valves employed are all by proference simple lifting conical-seated valves
worked by means of spindles passing through stuffing boxes where necessary and also
provided with springs whore desirable. The arrangement of the passages is the
same at both ends of the cylinder, and in each case there are three valves the
spindles of which extend downwards so as to be acted on by levers arranged below
the cylinder. The valve levers for both ends extend to a middle line below the
cylinder where they are acted on by tappets or cams on a rotating shaft driven from
the crank shaft so as to make one third the number of revolutions of that shaft.
The middle valve of each set of three is the exhaust valve and one side valve
is for admitting pure air, whilst the other side valve is for admitting the explosive
mixture of gas and air. The valve for admitting the mixture may be arranged to
simultaneously uncover suitably proportioned gas inlets and air inlets, or it may
have connected with it a separate annular or other valve for the gas inlets, the gas
and air inlets or passages being arranged so that the jets or currents are directed
across each other in order to obtain complete intermixture of the gas and air. In
one form of double valve the gas inlet is by an annular slit between two reversely
inclined conical surfaces and the valve is shaped to fit such surfaces and close the
annular slit.
Any suitable known igniting arrangement may be adopted, I however prefer to
employ a tube made red hot by an external Bunsen flame, with which tube there is
combined, with the view of preventing premature ignitions a small slide to close the
inner end of the tube except at the proper times for explosions. Or a plunger may
be arranged to enter the tube and to be withdrawn at the time for ignition. At
each end of the cylinder there is a space in which I fix one or more studs made of fire
clay or other refractory material for the purpose of retaining the heat in the
space.
For regulating the speed of the motor I employ a rotating governor connected
ith
ubo a ball invested in water To this is attached a cylindrical valve working

page_text: through a seat and made with angular or tapering openings. The motion of the
governor opens or closes the valvo if the normal speed of the engine increases or
diminishes. Or I may regulate the speed by means of a holl inverted in water
connected with a valve of the kind referred to. Beneath the hell there are two pipes
one being a discharge pipe communicating with the atmosphere the other a pipo
communicating with a pump or blower. A regulating valve is fitted on the discharge
pipe and is adjusted so that when the motor is working at the desired speed, the air
pumped in under the hell, passes out at the same rate, but if the speed increases, the
air is pumped in more rapidly than it can escape, which makes the hell rise or rice
rerai and shifts the gas valve accordingly. When starting the motor the gas vaive
being closed a bye-jass valve is employed to give a supply of gas direct until the
governing action is established.
Some of my improvements are applicable to single-acting motors.
Dated this Second day of February 1889.
EDMUND HUNT,
Applicant's Agent.
COMPLETE SPECIFICATION.
Improvements in Gas Motors.
I, DAVID BRUCE PEBBLES, of Tay Works, Bonnington, Edinburgh, in the County
of Mid Lothian, North Britain, 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, that is to say :-
My said Invention has for its object to improve the construction and operation
of gas motors; and is hereinafter describe with the aid of two accompanying sheets
of explanatory drawings, on which figure, 1, sheet, 1, is a plan of a gas motor
constructed according to one modification of my Invention, figure, 2, being a corre-
sponding vertical section. Figure, 3, on sheet, 2, is an enlarged horizontal section
of one end of the motor cylinder, and figures, 4, and 5, are transverse an I longitudinal
vertical sections. Figures, 6, 7, and 8, are sections of details and are hereinafter
described. In these drawings the same reference numerals are used to mark the same
or like parts wherever they are repeated.
In the modification of my improved gas motor shown in figures, 1, to 5, of the
drawings I employ a long double-acting plunger, 101, the ends of which work as pistons
in cylinders, 11, 12, at the opposite ends of a casting, 13, which may be internally a
continuous cylinder from end to end but which has at its middle part a slot having
projecting through it a strong stud. 14, fixed to the middle of the plunger, 10.
prefer to place the cylinders horizontally, as shown, with the plunger stud, 14,
projecting up through the slot made in the upper side of the cylinder casting, 18.
The plunger, 10, is by means of its stud, 14, and a connecting rod, 15, made to
act on a crank shaft, 16, placed with its axis at a level higher than the cylinders, so
that when the crank is in its lowest position the connecting rod, 15, extends nearly
horizontally just above the cylinders.
A mixture of air and gas is exploded twice af equal intervals during every three
revolutions of the crank shaft, 16, once in each cylinder, 11, 12; and the cyclo of
operations at one and or cylinder is as follows,-1, outstroke, taking in gas and
air, 2, instroke, compressing,-3, outstroke, exploding,-, instroke expelling
products, 5, ontstroke, drawing in air to clear the cylinder,and 6, instroke expelling
clearing air. When the explosion is taking place at one end or cylinder, 11 or 12,
the clearing air is being oxpelled at the other end or cylinder.
The valves employed are all, by preference, simple lifting conical-seated valves
worked by means of spindles passing through stuffing boxes where necessary, and
also provided with springs where desirable. The arrangement of the passages is the
same at both ends of the cylinder, and in each case there are three valves, 17, 18, 19,
the spindles of which extend downwards so as to be neted on by levers, 20, arranged

page_text: below the cylinder casting, 13. The valve levers, 20, for both ends extend to a middle
line where they are acted on by tappets or cam, 21, on a rotating shaft, 22, driven
from the crank shaft, 16, so as to make one third the number of revolutions of that
shaft. A pitch chain, 23, gearing with sprocket wheels on the shafts, 16, 22, is shown
in figures. 1, and 2, for transmitting the motion to the cans, 21; but any other
convenient gearing may be a lopted; and instead of the cam shaft, 22, rotating once
for every three revolutions of the crank shaft, 16, it may be arranged to rotate once
for every six (or other multiple of thre) revolutions of that shaft, the tappets or
cams, 21, being repeated a corresponding number of times. In one arrangement for
turning the cam shaft, 22, there is a ratchet wheel fixed on it and two pawl levers
worked from the crank shaft, 16, act upon it alternately.
The middle valve, 18, of each set of three is the exhaust valve, and one side
valve, 17, is for admitting puro air, whilst the other side valve, 19, is for admitting
the explosive mixture of gas and air. The side valves, 17, 19, are in lateral recesses
at the end of the cylinder, and a directing flange, 24, is provided between the inlet
valve, 17, for pure air and the exhaust valve, 18, to cause the entering current of
pure air to flow towards the piston so as to get between the piston and the remaining
used gasos, in order to expel the used gases us completely as possible.
The valve, 19, for admitting the mixture may be arranged to uncover suitably
proportioned gas inlets and air inlets, or it may have connected with it a separate
annular or other valve for the gas inlets, the gas and air inlets or passages being
arranged so that the jets or currents are directed across cach other in order to obtain
complete intermixture of the gas and air.
In the arrangement of combined gas and air inlets shown in figures, 4, and 5, the
gas is supplied by a pipe to a valve box, 25, in which there is a valve, 26, openod by
means of a spindle acted on by the same lever, 20, which opens the mixture inlet
valve, 19. The valve box, 25, communicatos with an annular passage, 27, in a
tubular piece, 28, the upper end of which forms the seat for the mixture inlet
valve, 19. At diametrically opposite points of the annular passage and at right angles
to the inlet into that passage it communicates with the lower ond of a passage, 29,
formed across the interior of the tubular piece, 28, and extending up nearly to the
top of it. The air which enters by a side passage, 30, passes up spaces, 31, on each
side of the middle gas passage, 29; and noar the top the gas issues from the middle
passage by sido openings and mixes with the air. Figure, 6, is an enlarged
horizontal section of the tubular piece, 28, as taken at the level of the openings through
which the gas issues.
In one form of double valve which is shown in section in figure, 7, the gas inlet
is by an annular slit, 32, between two reversely inclined conical surfaces forming a
seat to the valve, 33, which is shaped to fit on them and close the annular slit at the
same time that it closes the air passage, 31.
In figure, 2, the exhaust valve, 18, at the left-hand end or cylinder, 11, is shown
as open for the expulsion of the clearing air; and the tappets or cams, 21, shown as
acting on the levers, 20, are those which act on the levers of the valves at tho left-
hand end or cylinder, 11, whilst the relative positions of the tappets or cams for
neting on the valve levers of the right-hand end or cylinder, 12, are shown detached
at 34, below. Any suitable known igniting arrangement may be adopted, I however
prefer to employ a tube made red hot by an external Bunsen flame.
For regulating the speed of the motor I may use any suitable known arrangement
of gas-motor governor or I may employ a rotating governor connected with a valve
in the manner shown in figure, 8. In this arrangement a lever, 35, by which the
regulating action of the governor is transinitte is connected to a tube or bell, 36,
inverted in a liquid over another tube, 87, the bottom of which communicates with
the interior of a valve chamber, 38. To the top of the tube, 36, there is fixed by a
rod, 39, a cylindrical valve, 40, working through a valve seat, 41, to the upper side
of which the gas is supplied by a pipe, 42. The cylindrical valve, 40, the botto:n of
which is closed, is made with angular openings in its side, and when the speed
increases the valve is raised by which the supply is diminished as the gas has to

page_text: pass through the narrower parts in the openings into the space below the valve seat, Å1,
the gas proceeding thence by the pipe, 43, to the motor. A by-pass pipe, 44, with
a valve is provided to allow gas to pass without going through the regulating
valve, 40, whan the motor is being started. The valve rod, 39, may be passed through
n stuffing box if preferred.
Some of my improvements are applicable with single-acting motors; and the
double-acting motor may be worked as a single-acting one by removing the cams which
act on the valves at one end.
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. The improved combination of parts forming a double-acting gas motor, with
the cycle of operations at each end or cylinder extending over three revolutions of
the crank shaft, during one of which revolutions following one during which a charge
has been ignited and the larger part of the used gases expelled, pure or unmixed
air is drawn in and expelled preparatorily to the drawing in and compressing of the
next explosive charge, the parts of the motor being arranged and operating
substantially as hereinbefore described.
2. In a double-acting gas motor placing the crank shaft in a plane above or ou
of the plane passing through the axis of the cylinders and connecting the crank to
a stud projecting from the plunger or piston piece in the manner hereinbefore
described and as shown in the accompanying drawings.
3. The improved combination of parts comprising the valves and the parts or
gearing by which they are moved as hereinbefore described.
4. The improved combined air and gas inlet valve apparatus shown in figures, 4, 5,
and 6, of the accompanying drawings and hereinbefore described
5. The improved combined gas and air inlet valve shown in figure, 7, of the
accompanying drawings and hereinbefore described.
G. The regulating of the supply of gns to a gas motor by means of a rotating
governor combined with the valve apparatus shown in figure, 8, of the accompanying
drawings and hereinhefore described.
Dated this First day of November 1889.
EDMUND HUNT,
Applicant's Agent.