Improvements in Rotary Gas Engines, Parts of which Improvements are also applicable to Rotary Engines Driven by Steam, Air, Water, or other Fluid.
Year: 1889

page_text: Date of Application, 13th Dec., 1889
Complete Specification Left, 13th Sept., 1890-Accepted, 18th Oct., 1890
PROVISIONAL SPECIFICATION.
Improvements in Rotary Gas Engines, Parts of which Improvements
are also applicable to Rotary Engines Driven by Steam, Air,
Water, or other Fluid. ·
I, SAMUEL FORD, of 139 Hartington Road, South Lambeth, in the County of
Surrey, Engineer, do hereby declare the nature of the said invention to be as
follows:-
This invention relates more especially to improvements in rotary engines of the kind
in which a rotating drum revolves in a working cylinder on an axis eccentric to the said
cylinder, but concentric with the said drum, the said drum carrying with it two leaves
or slides forming the working pistons of the engine which said leaves or slides are
hinged on the axis concentric with the working cylinder and pass radially through
slots in the drum but always bear at their outer edges against the internal surface of
the working cylinder and the said improvements refer more especially to such engines
when employed as explosive or combustion gas engines; but they are also applicable
in part to such rotary engines when driven by steam, air, water, or other fluid.
One part of the invention consists in placing the inlet and outlet ports or passages
in rotary engines of the kind above mentioned at a distance apart of about one
quarter of the circuinference of the working cylinder, instead of being near together
as heretofore. By this means I am enabled to obtain, in gas engines or other engines
in which an elastic fluid is employed, a certain amount of expansive action of the
working fluid which cannot be obtained when the said ports or passages are placed
near together.
Another part of the invention more especially applicable to gas engines, consists in
certain mechanism for working the pump for forcing the charge of mixed gas and air
into the working cylinder, whereby the piston of the said pump is caused to move
faster at the latter part of its compression stroke than it would do by the ordinary
action of a crank or eccentric applied direct to the pump. The result of this is that
the whole charge of air and gas is forced out of the pump into the space behind the
leaf or slide by the time the said slide has reached the position where the charge is to
ignited. For this purpose I employ a crank on the central shaft of the engine and a
comparatively short connecting rod, one end of which takes on to the pin of the said
crank, and the other end of which is pin jointed to the end of an arm which oscillates
on a fulcrum pin, so placed with reference to the crank and connecting rod, that the
latter makes a smaller angle with the arm when the crank pin is describing one half
of its revolution than when it is describing the other half; the effect of which is that
the virtual leverage of the aforesaid arm is shortened during the time the pump piston
is making the latter portion of its compression stroke, whereby the speed of the said
piston is accelerated at that time. The aforesaid arm is connected to the piston of the
pump by any suitable mechanism such as levers, links and so forth.
For this
Another part of the invention, also more especially applicable to gas engines,
consists in certain arrangements of mechanism constituting a governor or regulator
for regulating the supply of gas to the engine according to the load.
purpose I employ a hit and miss arrangement for opening the valve admitting
gas to the air and gas compression pump, such hit and miss arrangement being
governed by a kind of air cataract. The gas valve is opened by a lever, and
closed by a spring. This lever is operated by a tongue piece moved to and fro
at. each revolution of the engine by means of a cam, lever, and spring. But,
interposed between the lever and the tongue piece is a moveable abutment piece,
the position of which with reference to the tongue piece is deperdent upon the
action of the aforesaid cateract. The cataract consists of a small pump the

page_text: -
plunger of which is connected with the abutment piece, and is actuated together
with the latter, by a cam and lever at each revolution of the engine. The pump
is furnished with an inlet valve and an outlet passage, the amount the latter is
allowed to open being regulated by means of an adjustable set screw. A weight
or spring tends constantly to force the cataract plunger, and its connected abutment
piece in one direction in opposition to the action of the actuating cam and lever.
Assuming now that the plunger has been raised by its cam and lever the abutment
piece will have been raised also into a position above the path of the tongue
piece. The raising of the plunger will have drawn into the barrel of the cataract
a charge of air. The weight or spring now begins to act to force down the
plunger and with it the abutment piece; but the speed with which the plunger
descends is dependent upon the speed with which the air below it can escape
through the outlet passage; and that speed is dependent upon the amount of
opening of the latter permitted by the regulating screw. If the plunger reaches
the bottom of its stroke in time to bring the abutment piece in line with the
tongue piece before the latter has completed its forward stroke, the tongue piece
strikes the abutment piece and thereby operates the lever which opens the gas
valve; but if the plunger does not reach the bottom of its stroke in time to bring
the abutment piece in line with the tongue piece before the latter has completed
its forward stroke, the tongue piece does not strike the abutment piece, and the
gas valve is not opened, consequently there is no explosion during the next revo-
lution, and the speed of the engine would be reduced until the time occupied in
a revolution is equal to that required to raise the plunger, and to allow it to
fall. So that whenever the engine, by reason of a reduction of its load, or from
other cause, exceeds the speed to which the cataract has been set, no gas is
admitted to the working cylinder until the speed has been reduced so as to conform
to, or correspond with that at which the cataract works. When the speed of the
engine falls below the normal the area of the outlet passage from the cataract is
to be increased by regulating the adjusting screw, the plunger then falls quicker,
and the speed of the engine increases in a corresponding ratio.
Another part of the invention, also applicable to rotary gas engines of the kind
above referred to, consists in placing an air inlet valve in the inlet port or passage to
the working cylinder; the object of this valve is to admit a charge of air behind the
second radial slide or piston to prevent on the one hand, the formation of a vacuum in
the working cylinder behind the said slide or piston, and to provide on the other hand
a. scavengering charge of air to sweep out any products of combustion that may have
remained in the inlet passage, or have passed into the space behind the second radial
slide or piston. It will be understood that the effort of the explosion is exerted only
on the first radial slide or piston, so that there is one explosion for each revolution
acting on one slide or piston, and a scavengering charge of air drawn in at each revo-
lution by the other slide or piston.
Another part of the invention, applicable generally to rotary engines of the kind
above referred to, relates to means for supporting the inner end of the fixed axis on
which the piston leaves or slides are hinged. For this purpose I provide a disc which
takes into a corresponding recess in the inner face of the end of the revolving drum,
and I pass the end of the aforesaid axis into a hole formed in the said disc, at a distance
from the centre thereof corresponding to the eccentricity or distance apart of the axes
of the working cylinder and of the revolving drum, and I secure the said end of the
aforesaid axis in the disc so that the latter cannot turn thereon, and, as the said axis
is also fixed so that it cannot turn, the revolving drum rotates on the aforesaid disc,
which is steadied in the recess in the end of the drum and becomes a support for the
otherwise unsupported end of the aforesaid fixed axis.
Dated this 13th day of December 1000

page_text: COMPLETE SPECIFICATION.
Improvements in Rotary Gas Engines, Parts of which Improvements
are also applicable to Rotary Engines Driven by Steam, Air,
Water, or other Fluid.
I, SAMUEL FORD, of 139 Hartington Road, South Lambeth, in the County of
Surrey, Engineer, do hereby declare the nature of the said 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 more especially to improvements in rotary engines of the kind
in which a rotating drum revolves in a working cylinder on an axis eccentric to the
said cylinder, but concentric with the said drum, the said drum carrying with it two
leaves or slides forming the working pistons of the engine which said leaves or slides
are hinged on the axis concentric with the working cylinder, and pass radially through
slots in the drum but always bear at their outer edges against the internal surface of
the working cylinder and the said improvements refer more especially to such engines
when employed as the explosive or combustion gas engines; but they are also
applicable in part to such rotary engines when driven by steam, air, water or other
fluid.
And in order that the said invention may be fully understood, I will proceed to
describe the same by reference to the accompanying five sheets of drawings, in
which
Figure 1 is a front elevation of a rotary gas engine constructed in accordance with
my invention;
Figure 2 a longitudinal section of same taken on line 1-2 of Figure 3;
Figure 3 a transverse section taken on line 3-4 of Figures 1 and 2;
Figure 4 an elevation of the right hand end of Figures 1 and 2;
Figure 5 a sectional elevation taken on line 5-6 of Figures 1 and 2; and
Figure 6 a partial plan.
A is the working cylinder, B the frame supporting same, C a frame carrying
the outer end of the main shaft D, E the flywheel, F the rotating drum cast with
or otherwise secured to the shaft D which is eccentric to the working cylinder A
but concentric with the said drum F. G G¹ are the two leaves or slides forming
the working pistons of the engine and hinged on the axis H secured at one end
in the cover A¹ of the working cylinder A and supported at the other end in a
disc I let into a recess in the end of the drum F as will be hereinafter more
fully described. The leaves or slides G G¹ pass radially through slots in the
drum F, as shown in Figure 3, but bear at their outer edges against the internal
surface of the working cylinder A, the varying angularity of the said leaves or
slides, caused by the eccentricity of the drum F with reference to the cylinder A,
being permitted by the segmental packing pieces J which are free to turn to the
required extent in cylindrical recesses bored longitudinally in the drum F as
shown clearly in Figure 3. K is the pump for forcing the charge of gas and
air into the working cylinder. L is the air inlet, M the chamber in which the
air and gas mix, N the valve for admitting gas to the mixing chamber M, O the
inlet valve to the pump for gas and air mixture, and P the delivering valve
between the pump and the working cylinder. All the parts so far described are
common to gas engines of the kind in question and I make no claim to them as
being of my invention.
One part of the invention consists in placing the inlet and outlet parts or passages
in rotary engines of the kind above mentioned at a distance apart of about one
quarter of the circumference of the working cylinder, instead of being near together
as heretofore. In Figure 3, A' represents the inlet port, and As the outlet port, the
latter being placed as shown a little more than a quarter of the circumference of the
working cylinder A away from the inlet port. By this means I am enabled to obtain,
in gas engines or other engines in which an elastic fluid is employed, a certain amount

page_text: of expansive action of the working fluid which cannot be obtained when the said ports
or passages are placed near together.
Another part of the invention, more especially applicable to gas engines, consists in
certain mechanism for working the pump for forcing the charge of mixed gas and
air into the working cylinder, whereby the piston of the said pump is caused to inove
faster at the latter part of its compression stroke than it would do by the ordinary
action of a crank or eccentric applied direct to the pump. The result of this is that
the whole charge of air and gas is forced out of the pump into the space behind the
leaf or slide G by the time the said slide has reached the position when the charge
is to be ignited, which is at or about the position shown in dotted lines in Figure 3.
For this purpose I employ a crank D¹ on the central shaft D of the engine, and a
comparatively short connecting rod D2, one end of which takes on to the pin D of the
said crank, and the other end of which is pin-jointed to the end of an arm D+ which
oscillates on a fulcrum pin D5 so placed with reference to the crank D¹ and connecting
rod D2, that the latter makes a smaller angle with the arm D', when the crank pin D³
is describing one half of its revolution, than when it is describing the other half; the
effect of which is that the virtual leverage of the aforesaid arm D is shortened during
the time the pump piston K¹ is making the latter portion of its compression stroke,
whereby the speed of the said piston is accelerated at that time. The aforesaid
arm D is connected to the piston K¹ of the pump K by any suitable mechanism such
as the connecting rod Do, lever arm D', weigh shaft Ds, lever arm K², and connecting
rod K³, for example.
Another part of the invention, also more especially applicable to gas engines,
consists in certain arrangements of mechanism constituting a governor or regulator
for regulating the supply of gas to the engine according to the load. For this purpose
I employ a hit and miss arrangement for opening the valve admitting gas to the air
and gas compression pump; such hit and miss arrangement being governed by a
kind of air cataract. The gas valve N is opened by a lever N₁ and closed by a
spring N2. This lever N¹ is operated by a tongue piece N³ moved to and fro at each
revolution of the engine by means of a cam N₁, lever N and spring No. But,
interposed between the lever N¹ and the tongue piece N³, is a moveable abutment
piece N, the position of which, with reference to the tongue piece N³, is dependent
upon the action of the aforesaid cataract. The cataract consists of a small pump N8
the plunger N° of which is connected with the abutment piece N', and is actuated,
together with the latter, by a cam N10 and lever N¹¹ at each revolution of the engine.
The pump is furnished with an inlet valve N12 and an outlet passage or valve N¹³, the
amount the latter is allowed to open being regulated by means of an adjustable set
screw N14. A weight N15, or a spring, tends constantly to force the cataract plunger N°
and its connected abutment piece N7 in one direction in opposition to the action of
the actuating cam N10 and lever N¹. Assuming now that the plunger N has been
raised by its cam N10 and lever N₁, the abutinent piece N' will have been raised also
into a position above the path of the tongue piece N³. The raising of the plunger
will have drawn into the barrel of the cataract N³ a charge of air. The weight N15,
or the spring, as the case may be, now begins to act to force down the plunger Nº,
and with it the abutment piece N'; but the speed with which the plunger descends is
dependent upon the speed with which the air below it can escape through the outlet
passage or valve N13 and that speed is dependent upon the amount of opening of the
latter permitted by the regulating screw N. If the plunger Nº reaches the bottom
of its stroke in time to bring the abutment piece N7 in line with the tongue piece N³
before the latter has completed its forward stroke, the tongue piece strikes the abut-
ment piece and thereby operates the lever N¹ which opens the gas valve N; but if
the plunger does not reach the bottom of its stroke in time to bring the abutment
piece in line with the tongue piece before the latter has completed its forward stroke,
the tongue piece does not strike the abutment piece, and the gas valve is not opened,
consequently there is no explosion during the next revolution, and the speed of the
engine is reduced until the time occupied in a revolution is at least equal to that
required to raise the plunger, and to allow it to full. So that whenever the engine,

page_text: by reason of a reduction of its load, or from other cause, exceeds the speed to which
the cataract has been set, no gas is admitted to the working cylinder until the speed
has been reduced so as to conform to, or correspond with, that at which the cataract
works. When the speed of the engine falls below the normal, the area of the outlet
passage from the cataract is to be increased by regulating the adjusting screw N14,
the plunger then falls quicker, and the speed of the engine increases in a corresponding
ratio.
If preferred the outlet passage or valve N¹s may be dispensed with and the air
caused to pass out of, as well as into, the pump barrel N8 through the inlet valve N12, the
latter being prevented from closing by the adjusting screw N15. The more closely
the valve N is allowed to close, the longer the time the plunger N° will occupy in
descending, and the slower will be the motion of the engine; and vice versâ the less
the valve N is allowed to close, the shorter the time the plunger N° will occupy in
descending, and the quicker will be the motion of the engine.
Another part of the invention, also applicable to rotary gas engines of the kind
above referred to, consists in placing an air inlet valve Q. in the inlet port or passage A²
to the working cylinder: the object of this valve is to admit a charge of air behind
the second radial slide or piston G' to prevent, on the one hand, the formation of a
vacuum in the working cylinder behind the said slide or piston and to provide, on the
other hand, a scavengering charge of air to sweep out any products of combustion that
may have remained in the inlet passage. It will be understood that the effort of the
explosion is exerted only on the first radial slide or piston G, so that there is one
explosion for each revolution acting on one slide or piston G, and a scavengering
charge of air drawn in at each revolution by the other slide or piston G¹.
Another part of the invention, applicable generally to rotary engines of the kind
above referred to, relates to means for supporting the inner end of the fixed axis H
on which the piston leaves or slides G G¹ are hinged. For this purpose I provide a
disc I which takes into a corresponding recess in the inner face of the end of the
revolving drum F, the said recess being concentric with the main shaft D, and I pass
the end of the aforesaid axis H into a hole formed in the said disc, as shown in
Figure 2, at a distance from the centre thereof corresponding to the eccentricity or
distance apart of the axes of the working cylinder and of the revolving drum, and
I secure the said end of the aforesaid axis in the disc so that the latter cannot
turn thereon, or I form the disc I in one with the end of the axis H and, as the said
axis H is also fixed to the cylinder cover A¹ so that it cannot turn, the revolving drum
rotates on the aforesaid dise I which is steadied in the recess in the end of the drum
and forms a support for the otherwise unsupported end of the aforesaid fixed
axis H.
It will be understood that the ignition of the charge of mixed air and gas in the
cylinder A may be effected by any of the usual means such as a red hot tube, an
electric spark, or, if the speed is not too great, by means of a gas burner in a slide ;
the moment of ignition may be governed by the passage of the leaf or slide G past a
hole G2 in one of the cylinder covers in communication with the means of ignition
employed.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
First In a rotary engine of the kind herein before referred to, placing the inlet
and outlet ports or passages at a distance apart of about one quarter of the circum-
ference of the working cylinder, as hereinbefore described, and illustrated in the
drawings, and for the purpose specified.
Second In a rotary gas engine of the kind herein before referred to, the mechanism
consisting of a crank D¹, a connecting rod D², and an oscillating arm D*, so connected
and arranged that the virtual leverage of the arm D' is shortened during the time the
pump piston is making the latter portion of its compression stroke, whereby the speed

page_text: of the said piston is accelerated at that time, substantially as herein before described,
and illustrated in the drawings, and for the purpose specified.
Third-In a rotary gas engine of the kind hereinbefore referred to, the governor or
regulator for regulating the supply of gas to the engine according to the load, con-
sisting of an air cataract, or pump and plunger acting on a movable abutment piece;
a reciprocating tongue piece which actuates the gas inlet valve by means of the
abutment piece, and mechanism for actuating the cataract, reciprocating tongue piece
and gas valve, combined, arranged, and operating substantially as hereinbefore
described, and illustrated in the drawings.
:
Fourth In a rotary gas engine of the kind herein before referred to, the use of an
air inlet valve in the inlet port or passage leading to the working cylinder, as herein-
before described and illustrated in the drawings, and for the purposes specified.
Fifth In a rotary engine of the kind hereinbefore referred to, the means of
supporting the inner end of the fixed axis H on which the piston leaves or slides are
hinged, consisting of the disc I taking into a recess in the inner face of the end of
the revolving drum F concentric with the main shaft, and having the inner end
of the said fixed axis secured eccentrically therein or formed therewith substantially as
herein before described, and illustrated in the drawings.
S. FORD.
Per W. H. Beck,
115, Cannon Street, London, Agent.