Improvements in Gas Motor Engines.
Year: 1890

page_text: Date of Application, 5th May, 1890
Complete Specification Left, 2nd Feb., 1891-Accepted, 7th Mar., 1891
PROVISIONAL SPECIFICATION.
Improvements in Gas Motor Engines.
1, JOHN FIELDING, of 39, Park Road, in the City and County of Gloucester,
Engineer, do hereby declare the nature of this invention to be as follows :-
The improvements to which this invention refers are in part more especially
applicable to engines of the four, and six, stroke cycles, and in part to gas motor
engines of other types.
The improvements may be divided under the following heads :-
Firstly. Improved means for obtaining greater expansion of the working charge.
Secondly. An improved form of admission and exhaust valve.
Thirdly. An improved governor for regulating the admission of gas.
Fourthly. Improvements in hot tube igniters.
Fifthly. An improved form of lubricator giving a constant delivery of oil.
Sixthly. Improvel methods and apparatus for facilitating the starting of gas
motor engines.
According to the first part of my invention I provide in connection with the
working cylinder, a separate chamber fitted with a valve, which at suitable times
opens or closes its connection therewith. The valve is operated by suitable means
such as a cam. Its action is as follows:-
Assuming that a charge has been drawn into the cylinder and that the piston is
about to perform its compression stroke, the valve will be opened allowing a portion
of the charge to enter the separate chamber, at any desired point of the compression
stroke the valve may be closed, the piston thereafter compressing the remaining por-
tion of the charge in the cylinder where it is ignited and on the following acting stroke
it expands to the full volume of the cylinder, the exhaust stroke then takes place,
expelling the products of combustion, and at some part of the next charging stroke,
the valve is re-opened permitting the pent up contents of the chamber to re-expand
into the cylinder. By retarding the opening of the admission valve, advantage may
be taken of whatever pressure may exist in the separate chamber to assist the forward
movement of the piston.
The amount of charge thus shut in the separate chamber may be varied for the
purpose of governing the engine by using a governor, acting on suitable stepped or
sloping cams to alter the timing of the valves.
The second part of my invention relates to a special form of combined admission
and exhaust valve consisting of a mitre valve working upon a seat preferably formed
on a removeable valve box bolted to the working cylinder, so that it opens inwards
to the combustion chamber. A spindle or stalk is formed on the valve, passing
through a sliding bush or collar held up to the under side of valve head by a spring
abutting upon a collar or shoulder on the valve spindle, the sliding bush is turned
at one part to fit freely in a bored part of the valve box separating an exhaust port
from the inlet port or chamber. At another part, viz. -where it abuts against the
underside of valve head it is reduced, leaving an annular space between the reduced
part and the inner diameter of the valve seat. The annular area permits the
passage of the waste products to the exhaust port when the valve is first raised
from its seat.
The shoulder formed at the junction between the larger and smaller diameters of
the sliding bush is caused to act as a valve for the purpose of closing the exhaust
outlet after the main valve has been raised through about two thirds of its total lift.
During this portion of the lifting movement the valve and sliding bush move
together until the shoulder comes in contact with a seat closing the exhaust, during
the remaining movement of the valve the sliding bush remains stationary and in

page_text: consequence a communication is formed through the sliding bush with the inlet
passage or chamber for the admission of the working charge.
The reverse motion of the valve first closes the admission, then re-opens the
exhaust, and finally closes all outer communication leading to the combustion
chamber.
The operations of the valve in relation to the movements of the piston are as
follows, riz.-
Assuming the piston to have reached the end of its acting stroke, the valve is
raised from its seat to about one third of its total lift, which allows the fullest area
for the escape of the waste products, whilst the piston is making its exhaust stroke.
At the end of this stroke the valve will have been raised another third of its lift,
closing the exhaust outlet, the remaining third admitting the fresh charge during
the suction stroke at the end of which the valve is quickly dropped to its seal
whilst the crank is passing the outer dead centre. Compression and ignition then
takes place whilst the valve remains closed.
According to the third part of my invention the governor consists of an unbalanced
rotating metal dise, which, as long as the normal speed is not exceeded is retained in
a concentric position by the pressure of a spring. Against the periphery of the disc
a wiper is so arranged that when owing to an excess of speed the dise assumes an
excentric position, it so acts upon the gas valve gear as to reduce or eut off the
supply of gas.
The dise is lightened or hollowed out over about one half of its surface, the other half
being suful, and it is either pivotted upon a pin carried by a flange on the shaft, or
it may be attached to a flai spring placed parallel with the shaft the spring being
secured at the other end to the side of the shaft.
According to the fourth part of my invention the lubricator consists of a closed
airtight chamber for containing the oil supply, having a tray or trough outside
formed in the same casting at the base of the chamber, a hole is drilled through the
wall of the chamber leading from its lower port into the tray, through this aperture
the oil escapes, maintaining a constant level in the tray, the oil is delivered from the
tray by a wiper, wick, or other suitable means, to the part to be lubricated. A
removable plug is provided for filling the oil chamber.
According to the fifth part of my invention in the Bunsen burner used for heating
the igniting tube, the mixture of gns and air issues laterally towards the centre from
an annular groove or chamber surrounding the tube thus inpinging directly upon it.
Air is supplied in suitable proportions below and above the flame to ensure perfect
combustion, the usual chimney or tube lined with non-conducting material is
provided above the burner which is arranged so that falling flakes or seals from the
tube may drop clear without danger of clogging up the gas or air passages, and
space is allowel beneath it to permit of a suitable tool being used to screw the tube
in or out.
To reduce the labour in starting gas motor engines it is frequently the practice to
provide some means of temporarily reducing the compression of the charge, and in
such enses where the timing of the ignition depends not upon the action of the
igniting valve, but upon the capacity of the tube beyond the heated part, it is
advantageous to have some convenient means, either- of increasing the space beyond
the heated part, or to reduce the distance between the heated part and the combus-
tion chamber, so that notwithstanding the lower compression the combustible mixture
will be able to reach the heated surface to effect ignition.
According to this part of my invention, on the outer end of the ignition the is
formel or attached a chamber of suitable capacity and a cork or screw plug is
provided for the purpose of opening or closing communication with the tube, thus
when starting with reduced compression, the cock would be opened until such time
as the engine had got up sufficient speed to permit of the full compression being
used when it would be shut.
Or in lieu of this arrangement, two passages, one longer than the other may be
arranged to lead from the hot tube to the cylinder, either, or both being fitted with

page_text: means for closing, when starting with low compression the long passage will be
closel, the other being open until the engine is fairly started and higher com-
pression used when the action of the passages may be reversed by closing the short,
and opening the long passage.
Thus in either case by suitably proportioning the parts, correct timing of the
ignition may be secured.
In cases where the engine is started under normal conditions of compression, the
chamber at one end of hot tube is also advantageous, but is employed in the reverse
manner, thus the cock is left open when engine is running, and closed for starting,
so as to retard the ignition until the crank has passed the dead centre, thus avoiding
the risk of premature ignition which might be dangerous to the attendant.
When for the purpose of starting gas motor engines, an explosive charge at or
slightly above the atmospheric pressure is introduced into the cylinder, the hot tube
as usually employed is unsuitable for igniting the charge and recourse is had to
electricity for this purpose, but according to a modification of the chamber fitted to
the end of the hot tube as already described such charges may be readily ignited,
this modification consists in the provision of an escape valve which may take the
form of a hinged flap opening inwards by gravity but arranged so that upon a sudden
pressure being created in the chamber it will shut.
The charge is ignited in the following manner : The pipe preferably placed
at the top of the cylinders and being at a bright red heat, the cock and flap valve
being both open, an explosive mixture is introduced to the cylinler under a slight
pressure.
As soon as the cylinder is filled, a draught being created in the tube by the heat,
the contents will rise up through the tube and escape by the valve until the
explosive mixture comes in contact with the heated surface of tube causing an
explosion, the pressure thereof shutting the valve and setting the engine into motion
with sufficient force to bring the ordinary cycle of operations into action.
The last part of my invention is for facilitating the manual starting of gas motor
engines of considerable power.
According to the usual practice, an engine has to be turned through one or more
complete revolutions, the power required to compress the charge being considerable,
particularly whilst the crank is passing the dead centre prior to ignition, so much
so, that various devices have been designed for the purpose of reducing the com-
pression during the starting operation. There is a further difficulty involved in
this method of starting when an engine is fitted with a hot tube igniter, and the
timing of the ignition depends upon the exact localization of the heated surface of
tube, in such cases there is a risk of the ignition taking place before the crank has
passed the dead centre prior to the commencement of the acting stroke involving
possible danger to the attendant owing to the engine being driven violently in the
wrong direction. According to this part of my invention the operation of starting
an engine will be as follows." It being assumed that the engine is standing with the
crank at the dead centre corresponding with highest compression no charge however
being in the cylinder, the valves all being closed, as will be the case under the
usual conditions of working.
The igniting tube being heated and the gas turned on, a suitable detent or pawl
is put into gear for the purpose of temporarily causing the air and gas valves to be
opened whilst the fly wheel is turned through about half a revolution which may be
done at a moderately slow speed, at the end of this movement, the engine auto-
matically throws the pawl out of gear allowing the valves to close, any desired
portion of a full charge may be drawn into the cylinder by suitably timing the
closing action. Now by turning the fly wheel backwards through say about one
quarter of a turn the charge will be ignited by the hot tube, and the consequent
explosion ill set the engine into motion, the ordinary cycle coming at once into
operation.
For very large engines, requiring more power than could conveniently be applied

page_text: direct to the fly wheel, suitable friction gear may be applied to its periphery for the
purpose of obtaining a purchase or leverage.
These improvements are applicable to internal combustion engines whether
operated by coal or oil gas, oil or spirit, vapour, or spray.
Dated this Third day of May 1890.
JOHN FIELDING.
COMPLETE SPECIFICATION.
Improvements in Gas Motor Engines.
I JOHN FIELDING late of 39 Park Road and now of Somerset Lawn in the City
and County of Gloucester 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 :—
The improvements to which this invention refers are in part more especially
applicable to engines of the four and six stroke cycles and in part to gas motor
engines of other types.
The improvements may be divided under the following heads riz.
Firstly. Improved means for obtaining greater expansion of the working charge.
Secondly. An improved form of admission and exlinust valve.
Thirdly. An improved governor for regulating the admission of gas, Th-
portion of the invention 1 now abandon,
Fourthly. Improvements in hot tube igniters.
Fifthly. An improved form of lubricator giving a constant delivery of oil.
Sixthly. Improved methods and apparatus for facilitating the Starting of gas
motor engines,
-
According to the first part of my invention, 1 provide in connection with the
working cylinder a separate chaualier fitted with a valve which at suitable time
opens or closes its connection therewith. The valve is operated by suitable means
such as a cam. The action is as follows
Assuming that a charge has been drawn into the cylinder and the piston is about
to perform its compression stroke the valve will be opened allowing a portion of the
charge to enter the seperate chamber. At any desired point of the compression
stroke the valve may be closed the piston thereafter compressing the remaining
portion of the charge in the cylinder where it is ignited and on the following acting
Stroke it expands to the full volume of the eylinder.
The exhaust stroke then takes place expelling the products of combustion and at
some part of the next charging stroke the valve is re-opened permitting the pent up
contents of the chamber to re-expand into the cylinder. By retarding the opening
of the admission valve advantage may be taken of whatever pressure may exist in
the separate chamber to assist the forward movement of the piston.
The amount of charge this shut in the separate chamber may be varied for the
purpose of governing the engine by using a governor acting on suitable stepped or
sloping cams to after the timing of the valves.
The second part of my invention relates to a special form of combined admission
and exhaust valve consisting of a mitre valve working upon a seat preferably formed
on a removable valve box holted to the working cylinder so that it opens inwards
to the combustion chamber, a spindle or stalk is formed on the valve passing through
a sliding bush or collar held up to the under side of valve head by a spring abutting
upon a collar or shoulder on the valve spindle, the sliding bush is turned at one part
to fit freely in a bored part of the valve box separating an exhaust port from the
inlet port or chamber, at another part riz. where it abuts against the underside of
valve head it is reduced leaving an annular space between the reduced part and the
inner diameter of the valve seat. The ammlar area permits the passage of the waste
products to the exhaust port when the valve is first raised from its sent.

page_text: The shoulder formed at the junction between the larger and smaller diameters of
the sliding bush is caused to act as a valve for the purpose of closing the exhaust
outlet after the main valve has been raised through about two thirds of its total lift.
During this portion of the lifting movement the valve and sliding bush move
together until the shoulder comes in contact with a seat closing the exhaust, during
the remaining movement of the valve the sliding bush remains stationary and in
consequence a communication is formed through the sliding bush with the inlet
passage or chamber for the admission of the working charge.
The reverse motion of the valve first closes the admission then reopens the
exhaust and finally closes all outer communications leading to the combustion
chamber.
The operations of the valve in relation to the movements of the piston are as
follows, ciz., assuming the piston to have reached the end of its acting stroke the
valve is raised from its seat to about one third of its total lift which allows the
fullest area for the escape of the waste products whilst the piston is making its
exhaust stroke at the end of this stroke the valve will have been raised another
third of its lift closing the exhaust outlet the remaining third admitting the fresh
charge during the suction stroke at the end of which the valve is quickly dropped
to its seat whilst the crank is passing the outer dead centre compression and ignition
then takes place whilst the valve remains closed.
The third part of my invention is now abandoned.
According to the fourth part of my invention the lubricator consists of a closed
air tight chamber for containing the oil supply having a tray or trough outside
formed in the same casting at the base of the chamber a hole is drilled through the
wall of the chamber leading from its lower port into the tray, through this aperture
the oil escapes maintaining a constant level in the tray, the oil is delivered from the
tray by a wiper, wick, or other suitable means to the part to be lubricated. A
removeable plug is provided for filling the oil chamber.
According to the fifth part of my invention in the Bunsen burner used for heating
the igniting tube, the mixture of gas and air issues laterally towards the centre from
an annular groove or chamber surrounding the tube thus impinging directly upon
it, air is supplied in suitable proportions below and above the flame to ensure
perfect combustion the usual chimney or tube lined with non-conducting material is
provided above the burner which is arranged so that falling flakes or scules from
the tube may drop clear without danger of clogging up the gas or air passages and
space is allowed beneath it to permit of a suitable tool being used to screw the tube
in or out.
To reduce the labour in starting gas motor engines it is frequently the practice
to provide some means of temporarily reducing the compression of the charge; and
in such cases, where the timing of the ignition depends not upon the action of the
igniting valve, but upon the capacity of the tube beyond the heated part it is
advantageous to have some convenient means either of increasing the space beyond
the heated part, or to reduce the distance between the heated part and the com-
bustion chamber, so that notwithstanding the lower compression, the combustible
mixture will be able to reach the heated surface to effect ignition.
According to this part of my invention on the outer end of the ignition tube is
formed or attached a chamber of suitable capacity and a cock or screw plug is
provided for the purpose of opening or closing communication with the tube, thus
when starting with reduced compression the cock would be opened until such time
as the engine had got up sufficient speed to permit of the full compression being
used when it would be shut.
Or in lieu of the arrangement two passages one longer than the other may be
arranged to lead from the hot tube to the cylinders either or both being fitted with
means for closing, when starting with low compression the long passage will be
closed, the other being open until the engine is fairly started and higher com-
pression used when the action of the passage may be reversed by closing the short,
and opening the long passage.

page_text: Thus in either case by suitably proportioning parts correct timing of the ignition
inay he secured.
In cases where the engine is started under normal conditions of compression the
chamber at one end of hot tube is also advantageous but is employed in the reverse
manner thus the cock is left open when engine is running and closed for starting so
as to retard the ignition until the crank has passed the dead centre thus avoiding
the risk of premature ignition which might be dangerous to the attendant. When
for the purpose of starting gas motor engines an explosive charge at or slightly
above the atmospheric pressure is introduced into the cylinder the hot tube as
usually employed is unsuitable for igniting the charge and recourse is had to
electricity for this purpose but according to a modification of the chamber fitted to
the end of the hot tube as already described such charges may be readily ignited,
this modification consists in the provision of an escape valve which may take the
form of a hinged flip opening inwards by gravity, but arranged so that upon a
sudden pressure being crented in the chamber it will shut,
The charge is ignited in the following manner, riz.,
The pipe preferably placed at the top of the cylinders and being ai a bright red
heat the cock and flap valve being both open an explosive mixture is introduced to
the cylinder under a light pressure.
As soon as the cylinder is filled a draught being created in the tube by the heat
the contents will rise up through the tube and escape by the valve until the
explosive mixture comes in contact with the heated surface of tube causing an
explosion, pressure thereof shutting the valve and setting the engine into motion
with sufficient force to bring the ordinary eyele of operations into action.
The last part of my invention is for facilitating the manual starting of
engines of considerable power. According to the usual practice an engine has to
be turned through one or more complete revolutions, the power required to compress
the charge being considerable particularly whilst the crank is passing the dead
centre prior to ignition, so much so, that various devices have been designed for the
purpose of reducing the compression during the starting operation.
gsmotor
There is a further difficulty involved in this method of starting when an engine
is fitted with a hot tube igniter and the timing of the ignition depends upon the
exact localization of the heated surface of tube in such cases there is a risk of the
ignition taking place before the crank has passed the deal centre prior to the com-
mencement of the acting stroke involving possible danger to the attendant owing to
the engine being driven violently in the wrong direction.
According to this part of my invention the operation of starting an engine will be
as follows.
It being assumed that the engine is standing with the crank at the dead centre
corresponding with highest compression no charge however being in the cylinder
the valves all being closed as will be the case under the usual conditions of
working.
The igniting tube being heated and the gas turned on a suitable detent or pawf
is put into gear for the purpose of temporarily causing the air and gas valves to be
opened whilst the fly wheel is turned through about half a revolution which may bo
done at a moderately slow speed, at the end of this movement the engine auto-
matically throws the pawl out of gear allowing the valve to close, any desired
portion of a full charge may be drawn into the cylinder by suitably timing the
closing action.
Now by turning the fly wheel backwards through say about one quarter of a turn
the charge will be ignited by the hot tube and the consequent explosion will set the
engine into motion the ordinary cycle coming at once into operation. For very
large engines requiring more power than could conveniently be applied direct to the
fly wheel suitable friction gear may be applied to its periphery for the purpose of
obtaining a purchase or loverage.
The improvements are applicable to internal combustion engines whether operated
by coal or oil gas, oil or spirit vapour or spray.

page_text: DESCRIPTION OF THE DRAWINGS.
Fig. 1 is a longitudinal section of the cylinder 1 of a gas motor engine, fitted
with my improvements. In this figure 2 is the expansion chamber and 3 the valve
in connection with same, shewn also at Fig. 3 which is an end elevation of the
cylinder shewing one method of working the valve 3 by means of a cam 4,
roller 5 and lever 6, the two projections 7 & 8 or cam 4 cause the opening of the
valve at the beginning of the compression and of the charging stroke, the shaft
rotating at half the speed of the crank shaft.
In Figs. 1, 2 and 4 the combined admission and exhaust valve is shewn at 9,
10 being the valve box, 11 the collar or sleeve held up against the under surface of
the valve by the spring 12, 13 is the exhaust passage and pipe, 14 the air inlet and
15 the gas valve working in gas chamber 16.
In Fig. 1 the valve is shewn closed, in the position occupied during the com-
pression and expansion of the charge.
In Fig. 2 the valve is in the position for exhaust, the waste products passing from
the cylinder under valve and out of passage and pipe 13. In Fig. 4 the valve is
raised to its highest position, the exhaust port being closed by the collar or sleeve 11,
the charge entering through the latter into the cylinder.
In Fig. 1, 17 is the igniting tube, 18 the Bunsen burner of which 19 is the
mixing chamber 20 and 21 respectively the air and gas inlets, 22 is the annular jet
for the issue of the flame, air joining same at 23 and 24 to assist combustion, 25 is
the chimney lined with non-conducting material.
Fig. 6 shews an igniting tube fitted with chamber 26, screw 27 and flap
valve 28.
Fig. 7 shews an igniting tube 29 connected to the cylinder by two passages 30
and 31 one of which is longer than the other, the communication being made to
either by means of a plug cock 32 or its equivalent.
In Fig. 1 are shewn at 33 the air tight oil reservoir 34 the tray forned with
saine, and at 35 the rotating wiper for delivering the oil from same into pipe 36
which conducts it to the cylinder.
In Figs. 2 and 5, 37 is the stud and 38 the strut used for temporarily opening the
air and gas valves, by means of the lever 39.
When the engine crank is at the dead centre corresponding with maximum com-
pression, the lever 39 will be in the position 394 and valves will be closed the stud
being at 37 but assuming that the engine has to be started, the strut must be placed
in position 384 so as to engage with the stud at 374, the valve still being closed.
Now on turning the flywheel forwards the valve shaft will turn in the direction
shewn by arrow the stud and strut will cause the valve lever to be depressed
opening the air and gas valves, until the position 37B and 38° are reached when the
piston will be at about half stroke and the valves will be fully open, further move-
iment will bring the stud and strut into position 37° and 38° when the piston will
have reached the end of its stroke and the valves will be closed, a slight continued
movement of the flywheel will move the stud sufficiently to clear the strut, allowing
the latter to fall out of gear into the position 38, the charge being now in the
cylinder is compressed by a backward movement of the flywheel into the igniting
tube and an explosion takes place setting the engine into motion.
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 motor engine the use of a chamber such as 2 separate from but con-
nected with the working cylinder such as 1 in combination with a valve such as 3
which (at suitable parts of the working cycle) opens and closes communication
therewith for the purpose of obtaining a greater expansion of the working charge,
substantially as described in reference to Figs. 1 and 3 in drawing.

page_text: 2. In a gas motor engine the use of the compound valve 9, 11, for the admission
and emission of the working charge, substantially as described in reference to
Figs. 1, 2 and 4 in the drawings.
3. In a gas motor engine the use of a single valve 1 for admission and exhaust
in combination with a loose valve box 10 substantially as described in reference to
Figs. 1, 2 and 4 in the drawing.
4. In a gas motor engine the use of a hot tube igniter having a Bunsen's flame
in the form of an anunlar jet surrounding the tube, such jet projecting laterally or
horizontally towards the centre and the tube, substantially as described in reference
to 22 Fig. 1 in the drawing.
5. In a gas motor engine the combination with an igniter tube of a chamber 26
and screw 27 or its equivalent either with or without the flap or equivalent back
pressure valve 28 substantially as described in referance to Fig. 6 in the
drawing.
6. The combination with an air tight reservoir 33 tray 34 and wiper 3.5 for use as
a lubricator for gas motor engines substantially as described in reference to Fig. 1
in the drawing.
7. Starting a gas motor engine by drawing into the cylinder a combustible charge
during what is normally the neting stroke of the piston and then by a backward
movement of the crank and piston causing the ignition of the charge by compressing
it into a hot tube igniter in the manner substantially as described.
8. For starting a gas motor engine the use of auxiliary gear for the purpose,
during the piston's normal acting stroke, of opening the air and gas admission
valves such apparatus being automatically thrown out of gear by the motion of the
engine to permit of the normal cycle being followed as soon as the engine is in
motion substantially as described.
9. In a gas motor engine, the employment for the purposes described in the two
preceding claims of the stud 37 and strut 38 in combination the lever 39 and
cam 40 substantially as described in reference to Figs. 3 and 8 in the drawing.
Dated this 31st day of January 1891.
JOHN FIELDING.