Improvements in Gas Engines.
Year: 1892

page_text: Date of Application, 11th Apr., 1892
Complete Specification Left, 30th Jan., 1893-Accepted, 11th Apr., 1893
PROVISIONAL SPECIFICATION.
Improvements in Gas Engines.
I, HENRY THOMAS DAWSON, of Salcombe, in the County of Devon, Gentleman,
do hereby declare the nature of this invention to be as follows:-
Though ignition tubes of porcelain or other earthenwares give rapid and certain
ignition rendering such tubes specially suitable for high speeds and while these
materials possess the additional advantage of practical permanence under the
necessary heat yet their liability to fracture constitutes a serious drawback to
their use.
With the object of remedying this defect and for the further improvement of
ignition apparatus such as is described and shewn in my Specification No. 6407 of
the year 1890 and No. 9865 of the year 1891, I make ignition tubes of porcelain,
earthenware or metal in sections jointed to each other so that one or more sections
may be replaced while greater freedom of expansion is allowed to each part of the
tube.
The sections forming the tube are held together tightly by a spring pressing upon
the end section through a plug or block as in the Specification No. 9865 of the
year 1891 which block may be of metal or the same material as the tube and which
may be chambered to contain the foul gases that first enter from the ignition port.
In some cases I corrugate the ignition tube. I further protect the ignition tube
by an envelope or sheath of tubular form upon which the heating flame plays
directly while the heat reaches the tube within by conduction and radiation. This
protecting envelope may be of metal or porcelain or such refractory material, and
may be corrugated in any suitable manner, with the object of further regulating the
passage of heat to the ignition tube within it, I sometimes arrange the envelope so
as to slide upon the ignition tube, to protect the latter while being heated, but when
sufficiently heated the envelope may be wholly or partially withdrawn, the flame
then acting directly upon the ignition tube. I may also use a suitably modified
Bunsen burner for heating the ignition tube.
This improved ignition tube and apparatus may be applied to other than the class
of gas engines described in my above named Specifications, with the object of
accelerating their ignition and thus increasing the speed and power at which such
engines may be worked.
For the application of my improved ignition apparatus to gas engines having a
slide valve I put the apparatus upon or construct it as part of the slide cover.
The
gas and air to supply the heating flame may be led to the point of combustion
either through passages in the slide valve or its cover or through exterior pipes as
may be convenient. The apparatus is to be so placed that the slide opens communi-
cation between the ignition tube and the compressed charge at the proper moment,
an arrangement being made for ventilation.
In gas engines having no slide valve I place the igniting apparatus in a position
upon the cylinder clear of the piston's travel. A valve is arranged in combination
with the apparatus which opens and closes the entrance from the combustion
chamber to the ignition tube at the proper times. The valve is worked from a
countershaft or other suitable moving part of the engine, by an eccentric, cam, or
other device.
My improvements thus enable me to bring the heated part of the igniting tube
in closer and more direct communication with the compressed charge than is usually
done thereby attaining higher speed and greater efficiency.
In applying these improvements to engines not fitted with an air compressor

page_text: I sometimes take a blast from the cylinder for heating the tube as shown in my
Patent 9865-1891.
I also improve upon the method of ignition shewn in my Specification No. 9865
of the year 1891, with this object I line the ignition chamber with refractory
non-conducting material arranged so as to take up the greatest heat from the
burning gas within the chamber and at the same time conduct it away as slowly as
possible. This may be done in a variety of ways all tending to present thin edges
or points to the flame and at the same time dividing the material into air spaces.
Preferably a series of thin discs or washers of fireclay or other refractory material
are employed so arranged as to have air spaces between them-the holes through
them being serrated or star shaped. The outer end of the chamber is closed by a
valve or door which may be opened for lighting and then fastened tightly to its seat
or which may be made to slightly open for ventilation when the chamber is closed
to the cylinder and close tightly when ignition is required by means of a lever and
cam arrangement worked by the engine-or a separate ventilating valve may be
similarly operated. An interior tube or plug serves to further confine and collect
the heat. The interior of the chamber is heated by the combustion of gas and air
supplied under pressure-when the engine attains a certain speed the heat of its
explosions will retain the igniter in a state of incandescence and the separate supply
of gas and air may then be cut off.
With the object of reducing the number of joints in a piston constructed according
to my Specification No. 9865 of the year 1891 I make the tube or shell of the
piston in one piece and fasten a cup shaped piston head or diaphragm within it in
such a manner that expansion of the diaphragm cannot affect the tube. The cup
like piece is fastened to the piston tube by its lip and the diaphragm being made
somewhat smaller than the interior of the tube, its expansion is spent upon the
elastic walls through which only it is connected with the piston tube, which is thus
left unaffected by heat applied to the diaphragm. A cover is provided forming
part of the connecting rod joint with the piston, and to lessen the metal required
for strength, a pillar or support projecting under the joint, touches the piston
diaphragm's inner face, so that the force of the explosions is transmitted directly to
the connecting rod.
I also interpose asbestos or other non-conducting material to prevent radiation of
heat from the diaphragm injuriously acting upon the joint of the connecting rod
with the piston.
I sometimes form the joint of the connecting rod with the piston as a portion of
a ball providing a considerable area to take the thrust of the piston, while the
tension strains are carried by a universal joint or gimbals, consisting of a ring or
frame through which the centre lines of two pairs of trunnions pass at right angles,
and these lines intersect one another at the centre of the ball, part of which forms
the thrust bearing so that the arrangement works freely but without slack.
The spherical part is seated upon the cover of the piston cup casting, while one
pair of trunnions are fixed to projections formed upon the cover, and the other pair
are formed upon the connecting rod, both pairs fitting into bearings formed at right
angles in the frame so that while the connecting rod can rotate the piston it can
also vibrate freely in every direction.
For more conveniently and efficiently governing high speed engines I use a
governor consisting of two or more arms or levers acting as weights, pivoted at one
end to a flywheel or other revolving part of the engine, and connected at their other
ends by rods, to lugs upon a sleeve fitting easily upon the shaft carrying the
governor, so as to give the sleeve partial rotation when the weights approach or
retreat from the centre. This partial rotation is converted into longitudinal move-
ment of the sleeve by spiral slots in which friction wheels or feathers work-or by
swing levers so arranged as to produce the required longitudinal movement.
Spiral springs extend from the lugs upon the sleeve or from some other con-
venient points, to the pins connecting the weight arms with the rods that move
the sleeve, so that the springs tend to resist divergence of the arms or weights,

page_text: and the adjustment of the engine's speed is effected by moving the pins and with
them both the springs and rods, along the weight arms, thereby increasing or
diminishing their leverage both over the springs and the rods.
A cam or cams are formed upon the governor sleeve, by which the admission
is controlled, or the governor may operate to regulate the opening of a valve, as
a throttle valve.
With the object of constructing gas engines of large power in order to obviate
irregular cavities in the combustion chambers such as valve boxes and to improve
the accessibility of the valves I construct the combustion chambers as much as
possible without corners, of a partially domed or bell shape, the proportions
varying with the size and requirements of the engine.
I use valves opening directly into the combustion chamber, so that when closed
they do not materially alter the interior form of the chamber.
I construct the valve seats and exterior connections so that each valve with its
seat and fittings can be withdrawn in one piece, and I may water jacket the exhaust
valve passage, or line it with non-conducting material to prevent the working parts
thereon becoming overheated.
The admission and exhaust valves are of mushroom type and are actuated by an
eccentric or eccentrics upon a shaft geared with the crank-shaft, revolving once for
each cycle of the engine, to which shaft the eccentric is fastened by an adjusting
clip similar to that shewn in my Patent 9865º¹.
The eccentric if only one is used, is so placed in relation to the admission and
exhaust valves that rods from it work the valves at the proper times and the rods
act upon levers fitted upon rocking shafts which work in bearings formed upon the
valve spindle casing. These shafts carry short arms or levers which bear upon
collars it may be furnished with friction rollers, fitted upon the valve spindles.
These arms are of such a shape as to lift the valve at first very slowly, then
quickly open it wide and nearly close it but finally bring it again very slowly
to its seat so as to allow quick running without the valves knocking upon their
seats.
The valve spindles fit. loosely in the collars upon them, which collars bear
against small shoulders formed on the spindles, so that while pressure upon the
collars can open the valves, the spindles and valves are free to turn round while
working or be turned by hand or otherwise to ensure the valves wearing truly
and keeping an accurate fit upon their seats.
The valves are normally kept closed by springs.
The igniting valve its spindle and the socket or bearing carrying the spindle
are so formed that they can be withdrawn together. The spindle has a collar
upon it forming a tight joint with the socket in which it works, and a spring washer
or other equivalent holds the collar to its bearing. The socket passes through
and is fitted in the walls of the combustion chamber, and it may carry packing
around the ignition valve spindle forming a gland. The igniting valve spindle is
preferably oscillated by a lever in connection either with the main valve eccentric
or a separate eccentric or cam upon the same shaft, with similar means to that
before described for adjusting the timing of the valve-and the spindle carries at the
end within the combustion chamber a bent arm upon which the igniting valve is so
attached that it is free to some extent to adjust itself and fit its seat accurately.
The igniting valve is kept open during the working and exhaust strokes for
ventilating the igniting apparatus. This may be of the kind described in my
Patent 98651 or of the modified forms herein described but in the construction of
gas engine now referred to the reel shaped plug forming part of the ignition
apparatus, has its inner end flush with the interior of the combustion chamber, and
the seat of the igniting valve is formed around the ignition aperture upon the inner
end of the plug.
The governing apparatus may be that shewn and described in my Patent 9865º¹.
Or the gas valve may be operated by the admission valve gear while the governor
through the medium of right and left handed screws moving a sleeve upon the

page_text: cycle shaft, is caused to interpose and shift a taper or stepped piece between the
adjoining parts of the gas and main admission valve gears, so that the gas valve is
either opened wholly or partially or not at all according to the work upon the
engine. I may use other methods of governing the engine's speed.
The gas after passing through the gas admission valve enters an annular passage
around the air admission port from which a series of small passages lead into and
distribute the gas evenly to the air supply. The gas supply is preferably cut off
just before the air so that the port outside the main admission valve is swept clear
of gas. The admission valve may be closed before the end of the charging stroke
to admit of greater expansion from the cylinder not being wholly filled with the
charge to atmospheric pressure.
To obtain a purer gaseous charge I sometimes admit a portion of air under
pressure just before the exhaust closes when the piston has already displaced most
of the burnt products, and this air further reduces the proportion of foul gases left
in the cylinder.
An automatic air valve it may be of any elastic material is placed in the air
passage outside the point of admission of the gas to the air, to prevent gas escaping
from the apparatus.
The piston may be of ordinary construction with rings or may be made in a
similar manner to that previously described, a trunk without rings being so attached
by a cup shaped piece to the piston face, as to be free from expansion by the heat
of the piston.
This engine being designed for high speeds for such purposes as driving dynamos
without belting is preferably made inverted and the crank and working parts are
lubricated by lubricant placed in an enclosed crank chamber, as in my Patent 9865º¹
but the engine may be made either vertical horizontal or otherwise and lubricated
in any suitable way.
When more power is desired than convenient from the use of a single cylinder
I couple a pair to drive one mainshaft, while one cycle shaft with one eccentric
may be arranged to drive the admission and exhaust valves of both cylinders and
the governor may similarly control the gas supply to both cylinders.
These improvements are designed to apply to an engine of the "four cycle"
type but may be used for other cycles.
Deted this 11th day of Aneil 1000
HENRY T. DAWSON.
COMPLETE SPECIFICATION.
Improvements in Gas Engines.
I, HENRY THOMAS DAWSON, of Salcombe, in the County of Devon,
Gentleman, 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 :-
My invention relates in part to improvements in gas engines having pistons
which rotate within the working cylinder and serve as valves, controlling the
admission of gas and air to the cylinder, the ignition of the charge therein and
the expulsion therefrom of the products of combustion; such engines are described
in the Specifications of former Patents granted to me especially in the Specifications
No. 6407 of the year 1890 and No. 9865 of the year 1891.
My invention relates in part also to gas engines in which the piston does not
rotate within the working chamber and separate valves control the admission,
ignition and expulsion of the charge and its products.
Some parts of my improvements also are applicable to engines of either class.
I will in the first place describe a gas engine of my invention in which the piston
has a reciprocating movement giving movement to the crank without itself rotating
and in which separate valves are provided for the admission ignition and exit.

page_text: After the
This engine is of the four cycle type, that is to say it takes its charge during the
outstroke of the piston, it compresses the charge during the instroke; whilst
the ignition takes place at the commencement of the next outstroke.
effective stroke and during the next instroke the products of combustion are
expelled. I generally arrange the engine with the cylinder inverted and vertically
over the crank but these arrangements are not essential.
I provide a combustion chamber upon the outer end of the cylinder and I
arrange the valves to open into this combustion chamber. The valves are
controlled by an eccentric and a cam upon a shaft parallel to the cylinder which
rotates once during the cycle of the engine. In connection with this axis also a
governor is provided for regulating the speed by controlling the gas admission.
I will proceed to describe the construction of the engine more in detail by
reference to the annexed drawings.
Figure 1 is an elevation and Figure 2 is a plan of the engine.
Figure 3 is a vertical section and Figure 4 is an horizontal section of the valve
and parts in connection therewith for admitting gas and air into the combustion
chamber of the engine.
Figure 5 is an elevation partly in section of some of the parts shown in Figure 4.
Figure 6 is an horizontal section of the combustion chamber and ignition apparatus.
Figure 7 is an elevation partly in section of the ignition valve and parts in
connection therewith.
Figure 8 shows a part of the ignition apparatus.
The
a is the cylinder of the engine, in it a piston works reciprocating but not rotating
and this piston by a connecting rod drives a crank upon the shaft b. bb² 63 are
fly wheels and belt pulley upon the crank shaft. The crank is enclosed in a
chamber containing oil or oil and water into which the crank dips. is an
eccentric upon the shaft which by gearing c such as is shown in my former
Specification No. 9865" gives motion to a piston in an air pump cylinder d.
air pump compresses a mixture of air and gas for the supply of the ignition
apparatus; it takes in air at the inlet d' and it also sucks a small quantity of gas
which is supplied by a pipe el connected with the gas main e. e is a regulating
cock with an indicator. The mixed gas and air is forced by the air pump down
the pipe past the stop cock finto the chamber y in the base of the engine where
it is stored under pressure as is described in my former Specification. g₁ is a
ventilating pipe and catch box in connection with the chamber y as before. his
a pipe leading the mixed gas and air to the ignition apparatus. is a vertical
shaft which call the "cycle" shaft, it is geared with the crank shaft at its lower
end; and rotates once for each cycle of the engine; it has at its upper end an
eccentric and a cam . The eccentric controls the admission of gas and air
to the cylinder and the exit of the products of combustion. The cam controls
the ignition valve.
The gas for the supply of the engine passes from the main e by the stop cock k
into the valve chamber and thence into the chamber m of the admission valve.
is a double beat valve in the chamber.
The valve is pressed to its seats by the spring but it is opened more or less
when the engine is running, being displaced by the rod n which is under the control
of the governor and the rollers p on the main valve stem. The end of the rod n
is inclined or it might be cut in steps.
o is the combustion chamber on the outer
end of the cylinder a, both it and the cylinder are kept cool by a water jacket o' ;
oo are pipes in connection with the water jacket. The combustion chamber o
has an aperture in its side into which a nozzle projecting from the valve chamber m
is fitted.
The gas after passing the valve enters by
valve chamber m and from thence when at suitable
opened, it passes into the combustion chamber.
pressure in the combustion chamber o is below
the perforations m' into the
times the main inlet valve is
When the valve p opens the
atmospheric pressure and the

page_text: indraught then causes gas to enter the combustion chamber together with air
which is drawn in at the inlet pl. The valve p is on a stem p' and a coiled
spring på holds the valve to its seat at the inner end of the nozzle of the valve
chamber m. In order to open the valve p at the proper times the fingers p' are
provided; they press against the rollers p mounted on a block p through which
the stem p passes; there is a shoulder on the stem against which the block presses
and this causes the opening of the valve. The spindle p² is free to turn in the
block and cross handles are provided for turning the valves. The fingers p
are on an axis p' and an arm p³ on the axis is connected by the eccentric rod with
the eccentric .
It will be observed in respect to the fingers p and the rollers that the fingers
are so formed that when the valve is closed, as is represented in the figure, that it
is the part of the finger near to the axis which bears upon the roller but as the
valve is progressively opened parts of the finger more and more remote from its
axis come into contact with the bowl and the opening of the valve is consequently
accelerated. Hence although the opening of the valve is sufficiently prompt it
will be moving but slowly at the moment when it is lifted from or replaced in its
seat; this improvement ensures a silent action.
The stem of the outlet valve passes through a valve chamber q; it is similar
to the inlet valve p and is opened by the same eccentric but at a different time.
The gases after leaving the combustion chamber and the valve chamber
away by a pipe g¹.
9 are led
There is an aperture and socket formed in the side of the combustion chamber o
to receive the ignition apparatus, which consists of a holder r containing fire clay
discs packed close one against the other also a perforated tube of refractory
Gas and air
material. One of these discs is shown separately at Figure 8.
passes from the pipe / past the stop valve into annular grooves formed around
the holder r and perforations opening from the grooves lead into the central cavity
of the holder r amongst the discs r. The gas and air is burnt in contact with
the discs and tube which consequently become highly heated. There are
openings at the ends of the holder r, that at the outer end is usually kept closed
by a door which is opened only for lighting and whilst the discs are warming.
The aperture at the other end of the holder r is opened and closed during the
The valves is
working of the engine, the ignition valves being seated upon it.
loosely jointed to an arm s¹ on the lower end of a spindle ; this spindle turns
in a bearing which is screwed into the combustion chamber and a coiled spring s³
presses the spindle outwards and holds a valvular enlargement upon it against the
lower end of the bearing and so makes a gas tight joint. An arm s¹ is fixed on
to the spindle and this is jointed to a rods which receives movement from the
cam. The rod has a bowl upon it which is held against the cam by a spring
not shown in the drawing. The valve s opens at a time when the gaseous charge
in the combustion chamber is compressed so that a portion of the charge
immediately enters amongst the discs r¹ and ignition ensues; the valve closing
before the next charge admitted.
The shaft by means of pulleys and a belt or otherwise drives a governor
consisting of an axis t carrying a disc t' which revolves with the axist and can
move along it. The weighted levers are jointed to the disc and as the weights
diverge by the centrifugal action, the shorter arms of the levers press upon a
collar upon the axis and the disc t¹ is thereby raised compressing the spring t³ and
moving the T form lever t about its fulcrum at t. Upon the head of the lever t
are teeth which when the lever is in mid position stand clear of the sleeve t which
is able to slide upon the shaft i but at other times the teeth engage with one or
other of the screw threads or worms which the sleeve has upon it. The worms are
right and left handed and according as one or other is engaged the sleeve as it
rotates slides to or fro. The weight of the sleeve if vertical supported by a
spring t. An angle lever to transmits the end wise movement of the sleeve to a

page_text: bar which is tapered or inclined at the end. The rollers on valve spindle p³
press upon the bar when valve p opens, and when the engine is running too
slowly bears against the end of the rod n, and unseats the valve 1; as the
speed of the engine increases the bar t' is withdrawn, and the valve opens less or
not at all.
Figure 9 shows another arrangement for the ignition apparatus and valve. An
aperture is formed in the side of the combustion chamber and in this there is
seated a metallic bobbin shaped block , such as is described in my former
Specification No. 9865" (see Figure 10). At the inner end of the block u, there
is an opening to which a porcelain or other ignition tube v is adapted; the tube v
is held in position as before by the pressure of a spring upon a block v¹ which
rests against its outer end. The block u is lined with fire clay, and gas and air
are supplied to the annular cavity u' around it. The gaseous mixture passes by
perforations into the interior of the block u, where it is burnt in contact with the
tube v, which is thus heated. u is wire gauze wound around the block to prevent
flame passing back. 20 is a chimney which carries off products of combustion.
is a valve within the combustion chamber o it is carried by an arm a¹ having a
globular end serving as a fulcrum, and which is held gas tight against a seat by a
spring y. The valve is moved as before by a cam upon the shaft i. By arranging
the block u as described with its face exposed in the combustion chamber,
the ignition tube is brought nearer to the charge to be ignited than would
otherwise be possible.
Figure 10 shows an ignition apparatus such as is described in my former
Specification but with improvements.
The porcelain or other ignition tube v is made in several separate ring like pieces
which are held together by the pressure of the block o at their outer end, this
renders the tube less liable to break, and if a ring should break it is more cheaply
replaced than the entire tube would be. Another improvement is that the tube
is corrugated externally, this renders it better able to endure sudden change of
temperature as when the gas is first ignited. In consequence of the action of the
ribs, the heat penetrates more gradually to the body of the tube. A third
improvement is that the ignition tube is surrounded by a shield v³, of metal or
refractory material, which shelters it to some extent when the gas is first turned
The shield should be corrugated in such manner preferably that its corrugations
cross those of the tube so that contact between the two occurs only at points,
the passage of heat from one to the other, is thus retarded and rendered more
equable.
on.
When the tube is warmed through, the shield can be drawn back so as to
expose the tube directly to the flame; is a stem attached to the shield v³ and
which serves to move it along the ignition tube. Gas and air are supplied by the
pipe h.
Figure 11 shows an ignition apparatus in which the ignition tube is heated by a
Bunsen burner z using gas at ordinary low pressure and atmospheric air urged
either by a chimney or by a blast. In the arrangement here shown the bobbin
like block u is dispensed with, the ignition tube abutting upon the wall of the
cylinder or combustion chamber of the engine.
Figure 12 shows my ignition apparatus applied to an engine in which a slide
valve is used to open the ignition port. A is the slide valve, B is the ignition port
in the wall of the combustion chamber. C is the slide valve cover, in and upon
the slide valve cover the ignition apparatus is mounted Ignition apparatus such
as I have described may be employed in engines of various types.
Figure 13 is a longitudinal section and shews part of a piston suited for an
engine of the class described in the Specifications of my former Patents,
No. 64070 and No. 9865". D is the piston tube in which are the apertures
serving to control the passage of the gases into and from the cylinder and also the
ignition of the charge. The tube D has within it a shoulder D', and this supports
the cup form diaphragm E. This diaphragm rests by its rim or edge upon the

page_text: shoulder D' and its sides do not touch the interior of the tube D, thus the head of
the diaphragm is free to expand under the heat to which it is exposed by the com-
bustion of the gaseous charge in contact with it. Stems E¹ E¹ connect the
diaphragm with the cover plate F. G is a disc of asbestos felt which is inserted to
impede the passage of heat; it is carried by the stems E' E' and by the pillar F¹.
The pillar F supports the diaphragm, and conveys the impulse given by the
explosion to the joint of the connecting rod, which is on the lower side of the cover
plate F.
Figure 14 shows a piston similar to Figure 13, and with it the joint and upper
end of the connecting rod. The joint is so formed that the pressure from the com-
bustion of the charge may be received upon a working surface of large area, whilst
at the same time suitable provision is made for the rotation of the piston together
with the head of the connecting rod H is the lower part of the connecting rod,
this part does not rotate, but it has a bearing upon it, in which the rotating
head H' is held, as is clearly shown and explained in the Specification No. 9865º¹.
On the upper end of the part H¹ there is a globular surface, which fits into a
corresponding recess at the underside of the piston. H'H' are trunnions projecting
from the part H₁; they are received into bearings in the gimbal ring I which
itself can rock upon trunnions II' which are held by the parts F' F' on the under
side of the piston all the bearing centre lines passing through the ball centre.
Figure 15 shows an underside view of the joint without the connecting rod. The
arrangements above described constitute a combined ball and socket and gimbal
joint the ball and socket parts support the pressure resulting from the ignition of
the charges whilst the gimbal parts receive the tension strains and ensure the piston
turning with the head of the connecting rod.
:
Figure 16 shews a front view and Figure 17 a side view of a governor suitable
for controlling the gas admission valve of a gas engine. K is an axis driven by
the engine and K' is a disc on the axis L L are two weight arms jointed to the disc
at L' L' they are drawn inwards towards the axis by coiled springs M M and are
driven outwards by centrifugal action. N is a sleeve loose on a boss at the centre
of the disc K' it has on it a series of cams N' N N N one or other of which by
operating on the bowl O moves the lever carrying the bowl and this opens and
closes the gas valve giving to the charge supplied to the engine more or less or no
gas as may be required. P is a pin furnished with a friction roller fast in the
boss upon the disc K¹ and passing through the inclined slot N in the sleeve
N N are lugs upon the sleeve which by the springs M and by links Q are connected
with the weight arms L L. The movement of the weight arms upon the
fulcra L'L' turns the sleeve N relatively to the disc K' and thence by the action
of the inclined slots N° and the pin P an end wise movement of the sleeve is
produced which causes one cam to pass out of action and another to take its place.
In place of the slot and pin, a link or links R may be substituted as is indicated in
Figure 18.
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 gas engine with a combustion chamber forming part of the cylinder and
which contains valves opening inwards for the passage of the gases into and from
the combustion chamber and for the ignition of the charge substantially as
described.
2. In a gas engine the combination of parts for the admission of gas to the
combustion chamber consisting of the valve p its stem p² the chamber m the
spring p the collar p" and the fingers p' suitably controlled to thrust the valve
open when required.
3. The like combination of parts to that mentioned in the second claiming clause
to control the outlet of the gases from the combustion chamber.
4. In a gas engine, valves opening inwards into the combustion chamber, held to

page_text: eir seats by springs and moved at suitable times by fingers in axes which are
sed partially to rotate and which fingers operate at short radius when the valve
bear to the seat and at longer radius when the distance of the valve from its seat
greater whereby more silent working at high speeds is obtained.
5. In a gas engine, the combination of parts consisting of a combustion chamber
ming part of the working cylinder and inlet, outlet and ignition valves in
nection with the combustion chamber such valves being controlled by an
centric and a cam on a shaft parallel to the cylinder, and revolving in time with
e engine's cycle.
6. In a gas engine a governor which through the medium of right and left
nded screws moves a sleeve and thereby shifts an inclined or stepped bar or
rt which by other gear receives a reciprocating movement and imparts the same
a gas admission valve, thereby suitably regulating the movement of the
d valve.
7. An ignition apparatus for a gas engine consisting of a holder containing.
cs of fire clay or other suitable pieces of refractory material and arrangements
admitting to the midst of the discs or pieces a mixture of gas and air which
ng burnt heats the discs or pieces; and arrangements by which the said heated
cs or pieces are enabled to ignite the charge in the combustion chamber of the
gine; the opening of a valve permitting a portion of the charge to pass to the
ated surfaces.
8. In an ignition apparatus of a gas engine consisting of a tube heated externally
a flame and from time to time opened to the charge
(a) Making the said tube of several separate rings held together by the
pressure of a block and spring.
(b) Providing a shield of metal or refractory material around the tube making
the said tute with external corrugations whereby when used in combination
with a shield it is rendered less liable to be fractured by sudden changes in
temperature.
(c) Providing a shield around the tube which when no longer required can be
withdrawn.
(d) Corrugating the shield to assist in regulating the passage of heat to
the tube.
(e) The combination with the said tube of a heating apparatus consisting of
a modified Bunsen burner using gas at low pressure with or without an air
blast.
(f) Combining such ignition apparatus with a slide valve mounting it in and
upon the cover of the valve.
(g) Combining with such ignition apparatus a valve within the combustion
chamber opening and closing the entrance to the ignition tube.
(h) Mounting the ignition tube upon a reel shaped block or plug and fitting
the same into an aperture in the combustion chamber with its face exposed
within the combusion chamber.
9. In a gas engine a reciprocating and revolving piston consisting of a tube
ting the interior of the cylinder and closed by a cup shaped diaphragm which is
e to expand without deforming the piston tube.
10. In a gas engine having a piston in accordance with the preceding claim, the
lar or support F1 transmitting the force of the explosion from the diaphragm to
e head of the connecting rod.
11. In a gas engine connecting a reciprocating and revolving piston with the
nnecting rod by a combined ball and gimbal joint.
12. In a gas engine a governor consisting of a disc with weight arms jointed to
and controlled by springs; a series of cams to actuate the gas admission valve
unted on the same axis with the disc and free to turn and to move end wise
ereon; links connecting the weight arms and the cams and a connection between
cams and the axis such as to compel the turning and end wise movements of
B

page_text: the cams on the axis to take place simultaneously. the whole so arranged that
when the weights move under the influence of centrifugal force the cams slide
along the axis and one passes into and another out of action.
Dated this 30th day of January 1893.
HENRY T. DAWSON.