IMPROVEMENTS IN ROTARY ENGINES
Year: 1863

page_text: PROVISIONAL SPECIFICATION left by William Clark at the Office of the
Commissioners of Patents, with his Petition, on the 16th May 1863.-
A communication from abroad by Adrien Jules Alexis Dumoulin, of
29, Boulevart St. Martin, Paris, Civil Engineer.
I, WILLIAM CLARK, of 53, Chancery Lane, in the County of Middlesex,
Engineer and Patent Agent, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN ROTARY ENGINES," to be as follows:-
This Invention relates to improvements in steam engines in which the
steam or other elastic fluid is discharged successively into spaces at a lower
and lower pressure, the principle of which is already known to science. These
improvements consist in the novel application of this principle, and in the form
and arrangement of the different parts, as follows:-1st, I make the steam to
pass through a series of passages a, b, c, d, e, f, g, h, of any suitable form, the
sections of which increase in determined proportions, and connected with a
series of annular concentric compartments A, B, C, D, E, F, G, H, so arranged
as to form a continuous channel for the steam. These channels, formed by
the circular walls or partitions m, n, o, p, q, r, s, are themselves of continually
increasing size in direct proportion to the volume occupied by the same weight.
of steam in connection with the pressure in each compartment. By reason of
the progressive increase in the size of these spaces the pressure decreases from
the central compartment A to the last one H. With the same initial pressure,
whether it be high or low, the successive expansion deducted from the
respective sections of each supply passage takes place by atmospheres or
fractions of atmospheres themselves, either at a constant or progressive pres-
sure, as, for example, 1 atmosphere, or it may be a half, a third, or a fourth
part of an atmosphere, until complete expansion takes place. The annular
compartments are consequently.inore or less numerous; according to the final

page_text: degree of expansion proposed to be obtained in order to produce the greatest
possible useful effect.
The second arrangement, which is alike essential, consists in returning the
steam by radial passages, after it has expended its force and has become com-
pletely expanded, towards the centre of the engine, whence it escapes to
the atmosphere or into a condenser. This arrangement has for object to
neutralize the effect of centrifugal force on the fluid motor during its action
on the engine, and consequently avoid, notwithstanding the speed of rotation,
the augmentation incident in the amount of fluid produced thereby, as also
the creation of an artificial counterpressure in the outer compartment H.
This pressure, which is also due to centrifugal force increasing with the angular
speed, maintains itself continually in equilibrium with the former, whatever
may be the speed of rotation; the one and the other are, in fact, of equal
intensity, but acting in contrary directions. This arrangement is, further,
entirely novel, as the increase in the supply of fluid which it obviates would
be not only pure loss, but would be inevitably detrimental to the useful effect
produced by the previous supply due to the natural initial pressure of the
steam.
I
I may also obtain the same result, although less completely, by means of two
other arrangements, which are, however, very difficult to realize in practice.
The first means consists in reversing the arrangement of the supply channels,.
as above described, as also that of the direction of motion of the fluid, by in-
creasing the size of said channels from the outer circumferential compartment H-
and causing the steam to flow from thence to the central compartment A,
which prevents the realization of other very important conditions.
The other method consists in allowing the steam to escape at the periphery
at an orifice of reduced size, so that it only allows during the movement of
the flow of the weight of steam admitted by the first orifice a in a unit of time,
notwitstanding the excess of pressure exerted by the centrifugal force. But
as this artificial pressure, created by centrifugal force in increasing the density.
of the fluid, varies with the angular speed of the engine, in order that the
equilibrium and the supply should be constant the section of the orifice
should vary with the speed of the motor, which is difficult to realize in
practice. The accumulation of water of condensation is prevented by means of
very small orifices x, x, by which it escapes by the action of centrifugal force.

page_text: The steam is admitted into the driving shaft o, o, which is bored for that
purpose, and furnished with a stuffing box and otherwise connected with the
supply pipe, whence it passes, by opening u and pipe v to the first passage a,
escaping at an orifice in said passage tangentially to the circumference into the
first annular compartment A, where it expands the fraction of an atmosphere
adopted, and thence passes, successively expanding in a similar manner, into
each of the compartments B, C, D, E, F, G, H, a reaction will thus be pro-
duced at each of the orifices a, b, c, d, e, f, g, h, the intensity of which depends
on the speed of the supply created by the difference of pressure existing in
each of the consecutive compartments till it reaches the outer one H, whence
the steam returns through the eight orifices M, M, and passages t, y, N,
towards the centre, where it finally escapes at the four openings K, K, either
into the atmosphere or into a condenser. The reaction produced by the flow
of the steam through the whole series of passages, being all exerted in the
same direction with regard to the axis, will effect the rotation of the whole
system, and the sum of these reactions, compared with the dynamic radius of
the apparatas, constitutes the motive power produced.
The apparatus may also be differently arranged without interfering with its
principal conditions; thus, the compartments, while remaining concentric, may
be placed at the same distance from the centre, that is to say, disposed late-
rally in the same plane of revolution, I, however, prefer the arrangement
represented as being more simple and satisfactory.
.
Instead of steam, any other fluid, either elastic or otherwise, may be used in
this apparatus (water, for example,) in all cases where this improved motor
may be usefully employed. This apparatus is especially applicable, from its
simplicity, small size, weight, and speed, for driving all kinds of machinery.
requiring to rotate at high speeds, as, for example, screw propellers, blowing
machines, turbines employed in refining sugars, hydro-extractors, and others.
In this case the rotary apparatus is mounted direct on a shaft common with
the apparatus it is to actuate. Its axis may be either arranged vertically or
horizontally, as the case may be. I also reserve its application for producing,
without adhesion or fulcrum, a rectilinear movement, such as that of railway
trains or boats. .