AN IMPROVED ROTARY ENGINE
Year: 1876

page_text: LETTERS PATENT to Pierre Bernard Martin, fils, of Bordeaux, Merchant, for tho
Invention of "AN IMPROVED ROTARY ENGINE."
PROVISIONAL SPECIFICATION left by the said Pierre Bernard Martin at
the Office of the Commissioners of Patents on the 13th December 1876.
PIERRE BERNARD MARTIN, fils, of Bordeaux, Merchant. "AN IMPROVED ROTARY
ENGINE."
My Invention consists in a novel construction of rotary motor engine to be
worked by steam or other fluid under pressure. Within an exterior fixed cylinder
I mount on a shaft which passes through packings at the ends of the cylinder an
inner rotating cylinder of smaller diameter than the former and eccentric to it, so
that it touches its interior at one side. To the rotating cylinder are jointed at
opposite points of its circumference two folding wings, which when folded inwards
lie in such a position as to form part of the circuinference of the rotating cylinder,
and can therefore pass its point of contact with the fixed cylinder, and when folded
outwards bear by their edges on the inner surface of the fixed cylinder. At the
end of the fixed cylinder is fitted a packing piece in the form of an annular piston,
behind which the working fluid is admitted, pressing it against the end of the rotat-
ing cylinder and thereby keeping the latter tight endways. Through a hole in this
packing piece the fluid passes into either of two grooves formed in the end of the
rotating cylinder, each of these grooves being of nearly semicircular form, extending
nearly half round the end of the rotating cylinder, and communicating with a
longitudinal groove extending lengthwise under each of the two folding wings.
The fluid entering by the hole in the packing piece into one of the grooves, presses
outwards the one of the folding wings and causes the inner cylinder to which it is
jointed to revolve, the one wing which is being pressed out by the fluid opening
out to accommodate itself to the eccentricity of the cylindrical surface on which its
edge bears, while the other wing is being folded inwards as it approaches the line of
contact of the two cylinders.
The supply of working fluid continues as long as any part of the semicircular
groove in the end of the rotating cylinder faces the supply hole in the packing piece.
By inserting a stop in any desired part of this semicircular groove the supply of
fluid can be cut off at any desired period of a revolution, permitting the fluid
D

page_text: already admitted to work expansively during the remainder of the revolution. The
fluid after having done its work, by pressing one of the wings round a great part of
a revolution, escapes by a discharge orifice in the side of the fixed cylinder near the
point of its contact with the rotating cylinder. Before however the one folding
wing reaches the point of discharge, the other has begun to be acted on by the
working fluid, and thus continued rotation of the inner cylinder is secured. In
order to render the line of contact of the inner and outer cylinders tight against the
leakage of the working fluid past it, notwithstanding wear, I mount in a cavity
provided in the outer cylinder at the line of contact a folding wing jointed so as to
fold in the opposite direction to those on the rotating cylinder, and I make a 1
communication by a small groove to the space under this wing, so that the
pressure of the working fluid always presses this wing against the surface of the
rotating cylinder.
Although I have described the admission of working fluid as taking place only
at one end of the cylinder, by the like arrangement of admission holes and 1
seinicircular grooves at the other end of the cylinder, the fluid may be admitted
also there.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Pierre Bernard Martin in the Great Seal Patent Office on the 12th
June 1877.
PIERRE BERNARD MARTIN, fils, of Bordeaux, Merchant. "AN IMPROVED ROTARY
ENGINE."
My Invention consists in a novel construction of rotary motor engine to be
worked by stean or other fluid under pressure. Within an exterior fixed cylinder
I mount on a shaft which passes through packings at the ends of the cylinder an
inner rotating cylinder of smaller diameter than the former and eccentric to it, so
that it touches its interior at one side. To the rotating cylinder are jointed at
opposite points of its circumference two folding wings, which when folded inwards
lie in such a position as to form part of the circumference of the rotating cylinder,
and can therefore pass its point of contact with the fixed cylinder, and when folded
outwards bear by their edges on the inner surface of the fixed cylinder. At the
end of the fixed cylinder is fitted a packing piece in the form of an annular piston,
behind which the working fluid is admitted, pressing it against the end of the
rotating cylinder and thereby keeping the latter tight endways. Through a hole in
this packing piece the fluid passes into either of two grooves formed in the end of
the rotating cylinder, each of these grooves being of nearly semicircular form,
extending nearly half round the end of the rotating cylinder, and communicating
with a longitudinal groove extending lengthwise under each of the two folding
wings. The fluid entering by the hole in the packing piece into one of the grooves,
presses outwards the one of the folding wings, and causes the inner cylinder to
which it is jointed to revolve, the one wing which is being pressed out by the fluid
opening out to accommodate itself to the eccentricity of the cylindrical surface on
which its edge bears, while the other wing is being folded inwards as it approaches
the line of contact of the two cylinders.
The supply of working fluid continues as long as any part of the semicircular
groove in the end of the rotating cylinder faces the supply hole in the packing
piece. By inserting a stop in any desired part of this semicircular groove the
supply of fluid can be cut off at any desired period of a revolution, permitting the
fluid already admitted to work expansively during the remainder of the revolution.
The fluid after having done its work, by pressing one of the wings round a great
part of a revolution, escapes by a discharge orifice in the side of the fixed cylinder
near the point of its contact with the rotating cylinder. Before however the one
folding wing reaches the point of discharge, the other has begun to be acted on by

page_text: the working fluid, and thus continued rotation of the inner cylinder is secured. In
order to render the line of contact of the inner and outer cylinders tight, against the
leakage of the working fluid past it, nothwithstanding wear, I mount in a cavity
provided in the outer cylinder at the line of contact a folding wing jointed so as to
fold in the opposite direction to those on the rotating cylinder, and I make a
communication by a small groove to the space under this wing, so that the
pressure of the working fluid always presses this wing against the surface of the
rotating cylinder.
Although I have described the admission of working fluid as taking place only
at one end of the cylinder, by the like arrangement of admission hole and
semicircular grooves at the other end of the cylinder, the fluid may be admitted
also thore.
Fig. 2.
Fig. 2 shews an end view of the engine with the cover removed.
Fig. 3 shews a cross section on line Y, Y.
Fig. 4 shews an inside view of the cylinder cover in which is fitted the piston
shaped packing.
Fig. 5 shews an end view of the engine with the cover removed as adapted for a
variable cut off.
Fig. 6 shews a part longitudinal section of the rotating cylinder.
The steam is supplied through the pipe O to the cavity Q between the cylinder
cover and the loose piston packing P which is thereby pressed against the end of
the rotating cylinder D, thus ensuring the steam-tight contact of the end surfaces
theroof with the outer cylinder. From the space Q, the steam enters the annular
space,, of the rotating cylinder D through the passage A. The cylinder D is
fixed on the shaft K eccentrically within the cylinder C, so that at one part of its
circumference it is contact with the latter. It has hinged to it at o, o¹, two
folding wings E, F, at opposite points, which when folded back as at E, fit into
corresponding recesses in the cylinder D, and when folded outwards as at F, bear
with their edges on the inner sarface of the cylinder C. Behind these wings small
channels a, a, are formed in the cylinder D, which communicate with the annular
spaces r,, so that the steam entering these will pass through such channels to the
back of the wings and tend to press these outwards against the cylinder C, and the
steam in filling the space between the two cylinders behind the wing will effect the
rotation of the cylinder. The annular space at the end of the cylinder D being
divided by radial partitions into two separate semicircular compartments, it will
be seen that when the one partition passes the inlet passage A, the steam supply
will be cut off from the one compartment, say ", and will enter the other, say 7L;
the steam is thus cut off from the space between the cylinders behind the wing F,
and when the cylinder D has rotated so far that the point of contact between F and
the cylinder C has passed beyond the exhaust passage M, the steam will escape
from the space behind F while it is entering the space behind E. The wing F will
at the same time by the rotation of the cylinder be gradully pressed back into its
recess as shewn at E. In order always to ensure a steam-tight contact between the
two cylinders, notwithstanding any wear, a flap N hinged to the cylinder C at oº,
and fitting in a cavity therein, is pressed against the cylinder D by steam pressure
which has access to the space behind it through a small channel c formed in the
cylinder C. The flap N hinged in the contrary direction to E and F, so that it
offers no obstacle to these in revolving. It will be seen that when the cylinder D
has revolved so far that the partition at r, in passing the steam port A, cuts off
the supply of steam to the space behind the wing F, the steam will then act
expansively in such space until it is made to communicate with the exhaust port as
described.
When it is required that the engine shall work with variable expansion, the

page_text: cylinder D is constructed as shewn at Figs. 5 and 6. The annular channels r, r¹,
have semicircular grooves g, g, h, h, formed in them for the reception of moveable
partitions G, G, so that in fitting these partitions in one or other of these grooves as
shewn, the supply of steam is limited to that portion of the channels 7, 1, between
the partitions G and the wings E, F.
In order not to have to remove the cover of the engine and packing piece A every
time the partition G requires to be shifted for varying the expansion, holes corre-
sponding with the form of the partition and closed by covers are made in the cover
and the packing, so that by turning the piston until the required grooves in the
channels r,, are brought opposite the holes, the partitions can be inserted through
them. The hinge joints of the wings E and F, and of the flap N, may either be
formned by a pin passing through eyes in the wings or flap as shewn at o², or they
may be more conveniently formed as at o¹ without any pin, the rounded parts being
merely forked so as to fit in between each other. The admission of steam behind
the piston packing P being limited to the annular space Q, the pressure exerted
thereby is only sufficient to maintain a steam-tight joint without producing any
such friction as would act as a brake on the cylinder D; the steam might however
be made to act upon the entire back surface of the packing if of low pressure.
The steam may either be introduced only at one end of the cylinder D, or at both
ends thereof, in which case both ends would be formed with the channels 7, 7º¹, as
indicated on the Drawing. A small notch is formed at f (Figs. 1 and 4) in the
packing P in order that the edge thereof may form no impediment to the motion of
the flap N.
Owing to the great speed at which the above described engine is capable of
running the steam might not be capable of expanding to the desired extent. In
this case two such engines might advantageously be arranged closely side by side,
the two revolving cylinders being fixed on one and the same shaft, and the exhaust
steam from the one engine be made to pass into the other engine to do duty therein
by expansion, as in ordinary compound engines.
Having thus described the nature of my Invention and in what manner the same
is to be performed, I claim,―
First. The construction of rotary engines wherein a revolving cylinder placed
eccentrically in a cylindrical casing has hinged to it two opposite wings, the free
ends of which are pressed against the surface of the casing by the fluid pressure
entering the space behind them from semicircular channels in the end or ends of the
cylinder, the steam being admitted to such channels through an inlet port in the
end surface of the cylindrical casing, substantially as herein described.
Second. The arrangement of the semicircular channels r, ¹, with fixed partitions
whereby the supply of steam is cut off, and with or without moveable partitions
whereby the expansive action of the steam may be varied.
Third. The arrangement of the piston packing P whereby the end surfaces of the
revolving cylinder are always made to work steam-tight.
Fourth. The use of the hinged flap N arranged and operating as described for
insuring the steam-tight contact between the circumference of the revolving
cylinder and the casing.
In witness whereof, I, the said Pierre Bernard Martin, fils, have hereunto set
my hand and seal, this Eighteenth day of May, in the year of our Lord
One thousand eight hundred and seventy-seven.
PIERRE BERNARD MARTIN, FILS. (L.S.)
Witness,
CH. ARMENGAUD,
Civil Engineer,
23, B. de Strasbourg,
à Paris.