Year: 1898

page_text: 1, FRANÇOIS ARNAUD, of 9, Faubourg Montmartre, Paris, France, Engineer, do
hereby declare the nature of this invention to be as follows:-
The present invention relates to steam,-gas,-petroleum-or other hydrocarbon-
engines and the special object thereof is is to provide a rotary engine with which
the moving power produced by explosion or expansion of fluid is directly trans-
mitted to the main-shaft by the cylinder of the engine without using a crank and
a connecting-rod or other parts of same character.
This engine is essentially composed of a fly-wheel mounted on the main shaft
and provided with one, two or more cavities forming cylinders, the longitudinal
axis of which being placed at a distance from the center of the fly-wheel equal
to the stroke of the pistons.
Within the cylinders are arranged the pistons, composed of a metallic cylinder,
provided peripherally with holes to ensure greasing and with circular grooves in
which are arranged elastic segments to prevent all escape of the motor-fluid.
Moreover, these pistons are closed by a plug screwed on the fore-part of said pis-
tons and provided with two projections, in which journals the axle-pin of a
grooved-pulley, rolling on an outer independent rail. This guiding rail, formed
of two equal parts in the shape of a hyperbolic spiral and provided with an inner
rib on which are rolling the grooved-pulleys of the pistons.
The guiding rail, by means of the grooved-pulley, serves as supporting point to
the pistons, to limit and to regulate the stroke of these pistons, the longitudinal
axis of which being always perpendicular or nearly perpendicular to the curvature
of the said rail.
The two parts forming the rail are connected with each other by means of
cramps and bolts and by a hinge allowing the upper part of the rail to be turned
aside; moreover, the rail carrys two crossbars, on the middle part of which are
arranged two bearings held by cap-pieces and in which journals the main shaft.
With this engine the distribution is effectuated by a slide-valve secured to one
of the crossbars and provided with inner suitable passages for admission and
exhaust of the motor-fluid. The passages of the distributing slide-valve com-
municate with the openings or ports arranged in the bottom of the cylinders by
means of metallic tubes, located in cavities made in the fly-wheel, said metallic
tubes being provided with a shoulder rubbing against the cylinder and the upper
face of which is pressed by a spiral spring to insure the tightness.
The engine being acted by gas, petroleum or any hydrocarbon, the inflamma-
tion of the explosive mixture is operated by a small pin with inner curved point,
passing through the wall of the cylinder and insulated from this wall by a tube
of porcelain or other insulating substance.
At its outer end this pin carries a catch acted by a cam of suitable shape secured
to a disk of black dyed caoutchouc or other insulating substance and arranged on
the distributing slide-valve. The lighting cam communicates with one of the

page_text: poles of a pile or any electrical supply, the other pole of which being connected
with the body of the engine, in such a way that, the lighting catch being no
longer acted by the cam, the lighting pin leaves the body of the engine and thus
causes production of a spark.
With this engine the motor fluid is acting by its pressure as with other engines;
but the forward stroke of the piston being limited and regulated by the guiding
rail, forming a fixed supporting point, the fluid produces its action on the bottom
of the working cylinder and thus communicates to the fly-wheel a movement of
rotation of reversed direction with regard to the movement of the piston.
The admission, expansion, compression and exhaust of the steam or gas is 1
operated with this engine as is done with ordinary engines.
Dated this 7th day of April 1898.
L. DUVINAGE, & Co.,
Patent Agent, 8, Rue des Princes, Brussels, Belgium.
1, FRANÇOIS ARNAUD, 9, Faubourg Montmartre, Paris, France, 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 present application relates to a rotary engine, worked with carburetted air,
compressed air, steam and the like, and in which the motive power, produced
by the explosion or expansion of these fluids is transmitted direct to the motor
shaft by the rotation of the motor cylinder or cylinders around this shaft. This
arrangement obviates the use of the connecting rod and of the crank. The motor
is not exposed to the prejudicial effect of the dead points, which are got rid of,
and consequently it is possible to secure great uniformity of working and con-
siderable speed of rotation.
These advantages result from the piston being forced, when in motion, to
follow the outline of a fixed cam a description of which will be given farther on.
In my Provisional Specification it is stated that: the piston rollers in running
are constantly supported against the interior concave surface of a suitably curved
rail.
I wish it to be understood that I may employ an alternative form of construction
which consists in causing these rollers to run, supported against the exterior con.
vex surface of the rail.
The annexed drawing illustrates, by way of example, a four-cylinder motor
actuated by carburetted air.
Fig. 1 shows the motor in elevation with its four cylinders; of which only one C
is seen with its distributing tube T and its piston P (Figs. 1 and 2).
Fig. 2 is a partial section of a cylinder as well as another section on a plane
passing through the line X' Y and through the axis of the motor shaft.
In the first of these sectional views, the piston P is seen and the cam K, the
outline of which is likewise seen in Fig. 1.
The respective axes of the four cylinders C C C C (Fig. 1) are situated in
one and the same plane, perpendicular to the axis of the motor shaft, and tangential
to a circle E F (Fig. 1) the centre of which is on the axis of the same motor shaft.
In each cylinder, a piston P (Figs. 1 and 2) moves. It consists of a cylindrical
body furnished with segments B (Fig. 2).
Two appendages m borne by the body of this piston, support, at their extremities,

page_text: a roller G which is moveable around an axis A, as also two other rollers g which
are moveable around their axes h:
During the rotation of the motor, the roller G rests constantly against the
cam . The extended (or continued) outline of this cam is composed of four
involutes of circles D, D¹, D2, D³, (Fig. 1).
The parts D and D₁ which relate to the motive and suction phases are parallel
to the involute of the circle E F enclosed by the different positions of the axes of
the cylinders.
Each of the two other parts D2 and D³ is parallel to the involute of a circle,
the diameter of which is suited to the duration of the exhaust and to the degree
of compression which it is desired to obtain.
The explosion chamber is formed by a tube T which comes against the bottom
of each cylinder and corresponds with a cylindrical distributing valve F furnished
with passages and ports H suitably arranged for the introduction of the explosive
mixture and the escape of the products of combustion.
The valve F and the cam K are fixed to a fixed hollow shaft I, around which
the cylinders rotate.
The valve is made air-tight by means of a spring L resting in part on the ledge
or shoulder M of the tube T and in part on the stuffing box N, and thus forcing
the tube T to rest constantly on the periphery of the valve F.
This system of distribution may be replaced by any other such as a set of
valves for instance. In like manner, the ignition of the explosive mixture may
be effected by means of an incandescent tube, or in any other way.
Electrically The fixed shaft I carries a disc made of insulating material, capable
of rotating around it. This disc has a flexible metallic plate R, which is joined
to one of the poles of the secondary current of a coil, the other pole communicating
with the body of the motor.
The tube T of each cylinder carries an igniting candle O. At each revolution
of the motor, the metallic part S of this candle comes into contact with the plate R
whence there is a closing of the current, and production of a spark between the
platinum wires n of the candle O which ignites the gaseous mixture.
Ignition being effected, the pressure produced in the interior of the cylinder
acts in part on the piston and in part on the bottom V, of the cylinder. As the
piston is maintained by the cam, the cylinder will rotate in the direction of the
arrow, in consequence of the leverage strain a, b.
During the motive and suction phases corresponding to the parts D, D', of the
cam (Fig. 1), the latter is normal, to the different positions of the axes of the
pistons. As the axis of each piston and that of its roller are in one and the same
plane it follows that the whole (piston-roller) for each cylinder is displaced on the
cam as on a horizontal plane, consequently without resistance.
Moreover, the expansive force of the fluid acts tangentially to the circle en-
closed by the different positions of the axis of each cylinder.
Thus by the combination of the parts mentioned above, this expansive force is
utilised to the utmost extent.
Each cylinder is four-cycle, but the four cycles are completed in a single
revolution of the motor.
If the roller of a piston passes over the part D1 of the cam, the explosive mixture
will be drawn into the cylinder. If the roller of a piston passes over the part. D³
of the cam, the explosive mixture will be compressed in the cylinder.
If the roller of a piston passes over the part D of the cam, the explosive mixture
will ignite and expand in the cylinder. If the roller of a piston passes over;
the part D3 of the cam the products of combustion in the cylinder will escape.
There is thus an act of impulsion for each revolution and for each cylinder.
For setting, the motor in action it is accordingly sufficient to cause the roller
When the
of one of the pistons to pass over the parts D₁ and D³ of the cam.
part D is entered on there will be an ignition and expansion, whence a rotation of

page_text: the corresponding cylinder. In consequence of the acquired speed, the suc-
cessive phases will be renewed.
One means of effecting the suction of the mixture of gas consists in the employ-
ment of a supporting rail U, the outline of which is parallel to that of the part D₁
of the cam (Figs. 1 and 2) and with which rail, during the time of the suction
phase, the two rollers g g supported by the before-mentioned appendages m of the
piston come into contact.
It is on this cam that the pistons of the cylinders find their support during the
motion of the motor, which thus transforms the reciprocating motion of its piston
or pistons into a continuous rotary motion.
I reserve the right of constructing motors according to this system, in any
size and of any material.
Further the pistons are guided by two slide bars X X in which the append-
ages m engage.
Une or more cylinders may be arranged with their axis or axes in one and the
same plane perpendicular to the axis of the motor shaft, and the axis or axes of which
are tangential to one and the same circle having its centre on the axis of the
motor shaft. But a series of several other cylinders may also be arranged, the
axes of which are situated in different planes, but parallel to the first, the rollers
"making contact" or not on one and the same shaft.
I would also observe that if the cylinder or cylinders are fixed and the cam and
its shaft moveable, a motor will be obtained similar in principle to the foregoing,
but rotating in a reverse direction to the same.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I claim
is:—
1. The arrangement of one or more cylinders having their axis or axes placed
in one and the same plane which is perpendicular to the axis of a shaft to which
such cylinder or cylinders are materially connected, the said axes being moreover
.tangential to a given circle having its centre on the axis of this shaft, as herein
described and set forth.
2- In combination with the foregoing the employment of a cam, the extended
or continued profile of which is composed of two involutes of circles corresponding
to the phases of motion and suction, and parallel to the involute of the circle
above mentioned, as well as of two other circle involutes parallel to the involute
of two circles the diameters of which are suited to the period of exhaustion and
to the degree of compression which it is desired to obtain, as herein described and
set forth.
3. The improved rotary engine constructed and operating substantially as herein
described and set forth.
+
1900
S. S. BROMHEAD.
Patent Agent, 171, Queen Victoria Street, London, E.C.