An Improved Rotary Steam Engine.
Year: 1891

page_text: Date of Application, 16th July, 1891-Accepted, 29th Aug., 1891
COMPLETE SPECIFICATION.
An Improved Rotary Steam Engine.
I, JOSEPH PIERRE COT of 34 Avenue d'Italie, Paris, in the Republic of
France, Grocer, 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 invention relates to an improved rotary steam engine, composed
principally of a central wheel carrying on its periphery a piston in the form of a
paddle or blade which moves under the action of the steam in a circular con-
centric space arranged between the wheel and the surrounding envelope or
cylinder.
This motor comprising amongst other things an appropriate distribution of steam,
will be well understood by aid of the accompanying drawing which represents a
sectional view of it.
As shown in the drawing, my motor is composed of a central wheel a fixed on a
horizontal shaft b, in the centre of a case or cylinder c, closed at the two ends by
caps or covers.
On the periphery of this wheel is a kind of piston d cast with it or connected
with it in any desired or convenient manner upon which the steam acts and thereby
causes the wheel to turn. For this purpose between the case or cylinder and the
wheel I have arranged a circular space e sufficient for the passage of the piston
and that of the steam which is to act on this piston to cause it to turn in this
space.
So that the steam may only act on one side of this piston I have arranged near
the admission cock, a kind of partition or abutment which divides the circular
space or chamber into two parts, but which at the desired time moves out of the
way to allow the piston to pass when it has completed its revolution.
For this purpose, on the shaft of the wheel, I have placed two cams g g
are keyed diametrically opposite to each other.
which
These cams are intended by the aid of connecting rods h. h to lift the partition
or abutment, in order to allow the piston to pass, and to allow it to fall again to
intercept the passage of steam in the reverse direction to that of the piston.
The connecting rods are guided in their motion by the rollers i. i.
The steam distribution cock f placed near the partition or abutment, is in com-
munication with the boiler by a tube.
The key of this cock is commanded by an arrangement of levers and connecting
rods j.j. which the central shaft puts in motion so that the cock is shut when the
piston has accomplished about three quarters of its course, in order that the steam
previously introduced behind the piston may expand during the remaining quarter
of the course of this piston.
The escape port formed by an opening & made through one of the ends, is placed
in relation to the partition or abutment, on the side opposite to that of the supply
cock, and the steam having completed its work escapes either into the open air or
is conducted into any suitable condenser.
The piston is furnished with any suitable kind of packing; this remark also
applies to the partition or abutment and to the periphery of the wheel.
A small blow out cock / is placed at the base of the motor.
The partition or abutment may be moved by any suitable mechanical arrange-
ment, such for instance as a rack &c. 1 will now explain the working of my
engine, supposing the parts to be in the position they occupy in the drawing, the
steam arriving by the distribution cock will act on the one side on the partition
or abutment g¹, and on the other side on the piston d; the partition or abutment
J

page_text: not being able to move, the piston will be pushed circularly, and when it has
arrived at about three-quarters of its course, the supply cock will be shut by the
arrangement of connecting rods above described.
The steam previously introduced will then expand and so cor plete its work on
the piston and it will finally escape by the escape port k.
A little while before the piston arrives at the partition or abutment, this latter
will be moved out of the way to allow it to pass, and in doing so will enter the
sheath m like a drawer and this piston will return to its first position and so on.
The piston d being solid with the wheel a as also with the horizontal shaft b
upon which it is mounted, it is sufficient to key on this shaft driving pulleys and to
provide the same with transmission straps in order to apply this motor to any
desired use.
It is well understood that I reserve the right to vary at will the form, details,
materials, dimensions, and accessories which may enter in my arrangement of engine
without departing from the peculiar nature of my invention
This motor can work by compressed air just as well as by steam.
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 :-
The new or improved rotary steam engine characterised by the arrangement of
a wheel a revolving in the interior of a case c by the action of steam which acts
upon a piston d on its periphery. This wheel being furnished with an arrangement
of cams g, keyed upon its shaft b so as to move by means of connecting rods ha
partition or abutment y¹ to retain the steam behind the piston d and to move it
out of the way to give passage to the piston at the required time. This engine
also comprises an arrangement of parts operated by an eccentric to regulate the
distribution of steam so as to secure an expansion of the latter, all substantially as
herein showu and described.
Dated the 16th day of July 1801