Improvements in and Connected with Gas and Vapour Engines.
Year: 1888

page_text: Improvements in and Connected with Gas and Vapour Engines.
We ARTHUR ROLLASON and JOHN HENRY HAMILTON both of 5 Grey Street,
Newcastle on Tyne in the county of Northumberland, Engineers, 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 relates to certain improvements in and connected with gas and
vapour engines and comprises constructional improvements in the appliances used in
connection with such engines for the purpose of facilitating starting, and of governing
and controlling the gas or vapour admission and pressure in such a manner as more
effectually to ensure the most economical consumption of such gas or vapour at all
times during working, and especially during variations of work and speed. The
improvements connected with the starting appliances constituting the first part of this
invention are applicable only to such engines as are provided with a reservoir for
containing a store of elastic fluid under pressure communicating with the working
cylinder of the engine, and which is charged with products of combustion or other
gaseous fluids by and during working of the engine, and from which a portion of such
accumulated gaseous fluid is admitted to the cylinder by valves in order to start the
piston from a state of rest: The improvements relate to the arrangement and dis-
position of the said valves and means of operating same when required for (1) charging
the reservoir and (2) starting the engine.
The improvements constituting the second part of our invention are applicable to
all classes of gas, vapour, or other fluid motor engines, and comprise improved con-
structions and arrangements of fluid admission and throttle valves and parts relating
thereto, and the invention also comprises improved means for operating the said
valves automatically to regulate the fluid supply in exact accord with the work being
done and the varying speeds of the motor: Such improved means consist of governors
and connections hereinafter set forth.

page_text: The invention also comprises improved means' whereby the gaseous fluid supply to
the engine may be rendered constant as far as practicable as hereinafter set forth.
We will now describe the first part of our invention referring in so doing to
figures 1 to 7 and diagram 8 of the accompanying drawings. Figures 1 and 2 are
respectively a back end and part left side elevation of the engine cylinder and storage
reservoir and connections. Figure 3 is an enlarged side elevation of valve casing and
operating gear. Figures 4 and 5 are vertical sections through centre thereof showing
operating gear in two different positions. Figure 6 is a horizontal section on
line 3. of figure 4. Figure 7 is a section through stop valve, and Figure 8 is a
diagram hereinafter referred to.
b
A is a receiver in which compressed gaseous fluid is stored during working of the
engine communicating by pipe C with combustion chamber or cylinder A¹ of the
engine, the stop valve B and valve casing D being interposed between the said reservoir
and the cylinder. The valve casing D communicates at its upper end through passage a
with the combustion chamber A of the cylinder, and at its lower end through
passage and pipe C with reservoir A. This casing contains two valves opening in
opposite directions, the upper valve c against the pressure in the cylinder and the
lower one d against the pressure in reservoir A. The space between the ends of the
valve stems is occupied by the end of a finger e attached to a spindle which latter
passes through a bush (see figure 6) and has secured to it an external crank arm g
which is connected by means of a connecting rod to a block h³ sliding in an
oscillating slotted link k; A handle may be attached to the end of connecting rod h
for convenience of altering its position and a catch y is fitted in connection with the
handle for retaining it in its end positions. The link k receives movement from a
cam E (figures 1, 2 and 5) on a rotary shaft driven by the engine through the medium
of a lever pivotted thereto and carrying a roller i. If the end of the connecting
rod be in the position shown in figure 4 then the cam E through the connection
aforesaid will lift the upper valve c, and if it be thrown over to the other end of
link the cam will cause the lower valve d to be pressed down and opened. The
upper valve e is suitably weighted and the weight causes it to return to its seat, but
a spring is used to close the lower one d. If it be desired to throw the apparatus
out of gear the free end of connecting rod h is placed at the middle of the link in
which position an angular movement imparted to the link does not cause either valve
to lift. The end of the link next the cylinder may then be pressed down and held
stationary by means of the retaining catch thus lifting the roller i clear of the cam
as shown in figure 5. Figure 7 is a section of the stop valve B. A hand wheel
attached to a screwed spindle which butts against the end of the retaining valve m as
shown is used when it is required to open this valve which is normally held up to its
seat by spring m³.
The action of the above described apparatus is as follows:-
To charge the reservoir A: The end of the connecting rod is pulled over by
means of the handle p figure 3 till it occupies the position shown in figure 4, and the
catch g figure 3 retains it in this position. The upper valve c will now be opened
by the cam E about the point of the piston stroke diagrammatically shown by 1 in
figure 8 and will remain open until the piston has reached the point 2 figure 8. The
gases from the cylinder at a high pressure as soon as the valve c is raised force open
the lower valve d and retaining valve m and thus a portion of the working charge
escapes into the receiver A; this goes on until the pressure therein is slightly below
that in the cylinder when the valve c opens. A pressure gauge may be attached to
the receiver A to indicate when the proper pressure is reached. The reservoir being
thus charged the end of connecting rod h may now be put into position shown in
figure 5 lifting the roller i clear of the cam E and the apparatus becomes idle as
described.
In order to start the engine: The end of connecting rod is to be placed at the
inner end of link k next the cylinder and the engine turned till the cam E just
begins to lift roller i and thus press down and open the lower valve d which occurs
when the piston comes to the point 1 figure 8 on its acting stroke. The retaining

page_text: valve m figure 7 is now opened by means of the hand wheel and screw and the gases
under pressure which were stored in the receiver A flow through the pipe Cand
lifting the valve crush into the cylinder and drive the piston forward. This operation
is repeated when the next acting stroke takes place unless the combustible mixture in
the cylinder should have ignited in which case the pressure in the cylinder being
higher than that below the valve c the pressure in the reservoir will not raise the
valve c and the engine continues to work without further exhausting the contents of
the reservoir. The next part of our invention refers to certain improved constructions
and arrangements of fluid admission and throttle valves their casings and connections.
Figure 11 is a horizontal section of one form and figure 12 a cross section through
valve casing and throttle valve. Figure 13 is a sectional plan of another form of
admission and throttle valve showing in plan operating connections to the governor
spindle, and figure 14 is a cross section through valves and casing of figure 13.
Figure 15 is an elevation of right hand side of figure 13 showing also the engine
cylinder and a governor partly in section.
A is the slide valve cover, a is a lift valve fitting closely and held by a spring d
against a seating in the casing b. This casing is provided with slots b₁ as shown in
the section figure 12. Enclosed in the same casing is the throttle valve e also provided
with wings and slots e¹ e' corresponding to those aforesaid and secured to a spindle f
capable of freely turning and also endway movement in a long bearing on the outer
end of the casing, and carrying on its outer end a sector g. This sector is operated
by the movement of the governor through connections best shown in figures 13 and 15.
The gaseous fluid enters through a passage in the slide valve cover and circulates
round an annular passage h. By the vibratory movement of the throttle valve the
area of the openings be is increased and diminished thus varying the fluid supply,
as required by the engine. The throttle valve e is not attached to the lift valve a and
does not touch the valve casing b thus being capable of moving very freely. By the
endway movement of the throttle valve spindle abutting against the valve stem the
valve a is opened at the periods required.
In the alternative construction of this appliance shown in figure 13 the fluid enters
from the cock k and the throttle valve e is of the form of a disc with portions e' cut
away and capable of turning freely. It does not fit tightly against the seating in
which the holes 61 for the passage of fluid are formed. The position of the throttle
is regulated by the position of the governor through the medium of connecting pieces
and gear shown in figures 13 and 15. A pin p attached to the sector g passes through a
sliding block and fork ended lever which in its turn is connected to the governor
and rises and falls with the latter, thus vibrating and partially closing or opening the
throttle valve e. For the purpose of opening lift valve a at the proper times a lever o
is centred on a bracket on the cylinder or governor, its lower end carries a roller o¹
which is actuated by a cam on the engine countershaft, the lever o carries at its
upper end a push piece 7 which pressing on the end of sector imparts the endway
motion which lifts the lift valve a. Should the governor rise to its highest
position the sector is lifted clear of the push piece q and the supply valve a is not
opened, on the other hand if the governor should fall below its working position a
pin lifting lever presses on one end of a lever m centred at m² on governor
bracket and carrying at its other end an adjustable counterweight m². Should the
speed of the engine still continue to fall the weight of the governor presses on the
end of the lever m raising the end carrying the counterweight m² at the same
time raising a pin s fixed on lever m off its seating in a catch t which when the
engine is working at its normal speed supports lever and counterweight m². The
continued downward pressure of the governor brings it to its lowest position in which
the top of the sector gis below the push piece y of lever o,
and thus should the engine
stop from any cause the fluid admission valve a will not be lifted or remain open.
The piece s on lever m may be placed in a recess on catch t in which case the catch
no longer supports the counter weight m² and the latter acting against the weight of
the governor body will lower the speed of the engine more or less according to its
position on lever m.

page_text: The invention also comprises certain improved constructions of governor. Figure 16
represents an enlarged half sectional elevation of one form of governor shown also on
a reduced scale in figure 15, and Figure 17 is a diagram illustrating the various
positions of arm and ball.
;
A is a heavy body with a loose cap C of suitable weight. B is one arm carrying
ball 6 the arm is centred on a pin E in a lug formed on spindle D. d d are oil
races. The upper surface of arm B is a portion of a circle which preferably passes
through the centre of pin E on which the arm works. The circular portion of the
arm bears against a flat surface a formed on the governor body A and as the arm
turns on the pin E the point of contact moves either towards or away from centre of
spindle D by properly adjusting the angle which this flat surface à makes with the
centre of the spindle D the arm B will roll upon this surface without any appreciable
slipping. Figure 17 is a diagram showing arm in middle and extreme end positions.
If the arm were to roll on this surface the centre of the pin E would trace out a
portion of a cycloid P, Q; the vertical line M N is a tangent to this cycloid at the
point E. The points of contact of arms in three positions are L L L" and the
moment of the weight of the body of the governor tending to turn the arm about
the centre of the pin E are proportional to distances between the points L' L L" and
the line M N. These distances may be made approximately proportional to the
moment of the centrifugal force of the ball and arm about the same point, in which
case the governor will be nearly isochronous and may be made as sensitive as
convenient by altering the curvature of the arm, the angle which the flat surface
makes with the vertical line, and the distance of point E from the centre line.
Another form of governing arrangement suitable for use where a throttle valve is
not required is illustrated in figures 18 and 19 which are respectively a part side and
back end elevation of engine cylinder and arrangements. In this the lift valve is
similar to valve a in figures 11 and 13 excepting that the stem a' of the valve is
prolonged and passes out through a bearing in the valve casing. The end of one
arm of a bell crank lever d opposite to the stem a' of the valve and the other arm
carries a roller b which is actuated from a cam plate (rotated with a shaft driven
by the engine.
The arrangement is shown in detail in figures 20 and 21 which are respectively a
front internal elevation of casing and governor and a cross section through centre
line.
The casing A is firmly fixed to the engine countershaft and within it riding freely
over the shaft and balanced on pins e and fixed in casing A is mounted the governor
body or frame d. This is of double curved or modified S shape as shown best in
figure 21 and to it is rigidly attached the cam plate C projecting through slot c' in
casing A. The tendency of the upper part of the S shaped frame d when rotated to
move in the direction of the arrow is resisted by a coiled spring s one end of which
is attached to frame D and the other to a star wheel capable of turning freely on
inner end of the pin e. The star wheel is held in any required angular position by
means of a flat spring t shown dotted in figure 21, which is secured to the
casing A.
The action of this governor is as follows:
The centrifugal force of the heavy parts of the frame D when the shaft is rotated
tends to move the cam plate C in the direction of the arrow; this centrifugal force is
resisted by the action of the spring s described above, but should the speed increase
nuly then the centrifugal force overpowers the action of the springs and the cam
riate will be moved in the direction shown by the arrow fig. 21 until it comes against
the side of its slot c¹ in casing A, as shown dotted fig. 21. In this position it misses
the roller 6 therefore the bell crank a is not operated and no fluid is admitted to the
Engine as the speed decreases the plate C moves back to the position to which it is
adjusted as in fig. 21, and the admission valve will be again lifted. If it is
desired to change the speed of the Engine the power of spring may be
altered by pressing down the end of the spring and turning the star wheel h
about its centre with any angular motion proportionate to the speed desired.

page_text: The improved means for rendering the supply of gaseous fluid to the Engine constant
as far as practicable in spite of variation of speed and work are illustrated in figs. 22,
23, 24. Fig. 22 is a cross section on centre line of one apparatus, and fig. 23 is a
side elevation of an alternative apparatus fig. 24 being an enlarged sectional view of
upper part thereof.
A is a casing of cast iron or suitable metal having supply port. E in which is
seated valve C and delivery port F. In the casing is fixed a flexible diaphragm B
upon which one arm d of a bell crank lever D presses; its other arm d' acts on the
base of the valve C as shown in Fig. 22. If the valve C be open fluid enters casing A
and by its pressure forces diaphragm B outwards and the weight of the valve Con
the end of horizontal portion of arm d' of Bell-crank D causes other arm of lever d
to follow the diaphragm and thus the valve is closed.
In the arrangement illustrated in figs. 23, 24 instead of a bell crank lever a
supplementary diaphragm g is introduced in connection with the gas passage E, and
in communication on its lower side with the cavity of casing A; the valve C being
interposed as shown.
Fluid entering through E passes valve if open and through E¹ into the
casing A. When pressure therein increases unduly it is exerted on the lower
surface of diaphragm g thus raising and partially or entirely closing valve C.
The upper surface of diaphragm g communicates with the atmosphere, and extra
weight may be placed on the stem of the valve C according to pressure required in
casing A.
Having now particularly described and ascertained the nature of our said Inven-
tion and the manner in which the same is to be performed we declare that what we
claim is :-
1. In a gas or vapour engine provided with a pressure reservoir such as A con-
nected with the engine Cylinder by a pipe having a retaining valve for the purpose of
starting the engine. The arrangement in an intermediate casing of 2 valves adapted
to be opened in opposite directions the upper one against the pressure in the Cylinder
the lower one against the pressure in the reservoir by means of link-work and levers
operated by one cam or equivalent driven by the Engine substantially as and for the
purposes set forth.
2. The combination with a reservoir A having retaining Valve m Engine Cylinder A¹
and connecting pipe C of valve casing D two valves c & d connections e, f, g, h, link k
and means of operating same at the times and for the purposes set forth in reference
to Figs. 1 to 8 of the accompanying drawings.
3. The improved constructions and arrangements for regulating the admission of
Gaseous fluid to gas and vapour engines substantially as hereinbefore described with
reference to Figs. 11 and 12, 13 and 14.
4. In an appliance for regulating the admission of gaseous fluid to an engine
Cylinder the arrangement of a Cylindrical or disc throttle valve adapted to vibrate
centrally in a casing with an annular space intervening in combination with a supply
valve adapted to be lifted both constructed as specified the former operated
by the Governor so as to vary the admission area in proportion to its motion and
the latter adapted to be operated by the Engine when required substantially as set
forth.
5. The improved construction and arrangement of Governor for Gas and vapour
engines substantially as described and illustrated in figs. 15. 16. 17.
6. In a Governor for Gas or vapour engines the use of arms and balls in com-
bination with a weighted body, the arms having their upper surfaces seginental and
adapted in action to roll in contact with a flat surface or surfaces on the said
weighted body and arranged and operating as described in reference to Figs. 16
and 17.
7. The improved arrangement of gear for communicating the movements of the
Governor to the throttle and lift valves e. a. herein before described and illustrated in
figs. 13 and 15, by which the throttle valve e receives movement from and varying

page_text: with the Governor, and the left valve through a lever from a shaft driven by the
Engine at the times and in the manner set forth.
8. In an appliance for ensuring constant fluid pressure supply to a gas or vapour
Engine the combination with a casing containing a flexible diaphragm of an internal
bell crank lever adapted to be actuated by said diaphragm so as to operate a valve at
the times and for the purpose set forth in reference to fig. 22.
9. The combination of parts forming the alternative construction of appliance
illustrated in figs. 23 and 24, for the purpose mentioned in the preceding claim.
1 1
2
1 1000
J. C. CHAPMAN,
70, Chancery Lane, London, W.C.,
Patent Agent.
J. C. CHAPMAN,
70, Chancery Lane, London, W.C.,
Patent Agent.