AN IMPROVED ROTARY ENGINE."
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Charles Ménard at the Office of the
Commissioners of Patents on the 20th March 1880.
16
CHARLES MÉNARD, of Paris, 33, Ruo des Écoles, in the Republic of France.
AN IMPROVED ROTARY ENGINE."
This improved motor is enclosed within a hermetically closed metallic casing, and
turns within it round a shaft, which serves as its axis, by the action of compressed
air or any gas.
This shaft which passes through the inetallic and hermetically closed casing is
hollow, and made of either cast or forged iron, and is furnished with stuffing
boxes.
The principal part of this motor is a motive wheel mounted on the said
shaft, and provided with two slido valves which are diagonally opposito one
another.
These two slido valves do not in any way influence the action of the motive
wheel, for being completely independent and isolated from the wheel they may
be considered as being suspended in space. The pressure exerted on their surface
is counterbalanced by the resistance of rods which turn round two fixed cylinders.
So as to prevent all penetration of air or gas under the slide valves they are
provided with a packing of india-rubber or other suitable substance.
Two discs serving to support the motive wheel are also fixed to the main shaft,
and are placed one on the right and the other on the left of the wheel.
Two shafts diametrically opposed are fixed on the two discs and serve as supports
to two levers. To one of the extremities of each of these levers is fixed an iron
rod connected with one of the slide valves of the motive wheel, and at the other
extremity of the said levers is fixed an iron cross-pieco or bar, which carries at each
extremity two metallic rods. These two rods fixed to the cross-piece or bar
surround two fixed knobs round which they have a rotary motion, at the same
time resisting the pressure exerted on the slide valve.
The two flat surfaces contiguous to the slido valves exercise a continual pressure
tending to make the whole of the mechanism turn round the axis or hollow shaft,
and they have only to overcome the resistance of the collars against the fixed
cylinders.

page_text: A tube called a discharge pipe puts each of the slide valve chests in communi-
cation with the hollow shaft so as to prevent the accumulation of pressure under
the slide valves.
The pressure being normally exerted on the surfaces in the middle surrounding
the two flat conical surfaces of the slide valves have only to overcome the resistance
of the collars.
Now as it is well known that a shaft turning in bearings exercises a resistance
equal to one tenth of the weight it supports, consequently the resistance to be
overcome by the two surfaces contiguous to the pistons is equal to one tenth
of the pressure exerted on the piston, that is to say, one tenth of the power is lost.
In ordinary machines as much as one half of the power is lost.
This mechanical motor enclosed in a hermetically closed casing is moved in a
rotary manner by the aid of compressed air or gas, and has only to compensato for
the inevitable losses by the pores of the casing and the joints.
"
This apparatus being very simple its-employment realises great advantages over
existing machines, and when once charged it will operate several days without any
necessity of renewing the provision of air or gas.
It may be employed in all cases where machines actuated by steam or other
motive force are now used, and is destined to replace ordinary cylinders.