Improvements in Rotary Engines, applicable also as Pumps.
Year: 1899

page_text: Date of Application, 2nd Aug., 1899
Complete Specification Left, 2nd May, 1900-Accepted, 28th July,
1900
PROVISIONAL SPECIFICATION.
Improvements in Rotary Engines, applicable also as Pumps.
We, DAVID CARTER, Engineer, of 6, Ashtree Road, Stirchley, near Birming-
ham, and CHARLES JOHN SMITH, Carriage Builder, of Godalming, in the County
of Surrey, do hereby declare the nature of this invention to be as follows:-
This invention relates to rotary engines of that class in which two cylinders
on parallel shafts are geared together the circumference of one cylinder being
in contact with the other for the greater part of their revolution--and in which
one cylinder has a radial piston extending from it at one part of its circum-
ference and the other (which forms a rotating abutment) has a recess in its
circumference which allows the piston to pass as the cylinders revolve-and in
which also a cylindrical casing surrounds the rotating cylinders the piston on
the one cylinder fitting to the interior of one portion of the casing and the
remainder of the casing fitting around the cylindrical abutment.
According to this invention two such engines are formed together end to end.
The cylinders which carry the pistons are upon one shaft which extends through
both the cylindrical abutments are upon another shaft which also extends
through both and the piston of one division of the engine is set on the opposite
side of the shaft to the piston of the other division so that when one piston is
passing the abutment which works with it the other has upon it a full pressure
of steam.
For admitting steam to and allowing it to pass from the annular space around
which the radial piston of each division travels two passages are formed opening
into the annular space of that division on either side of and close to the abut-
ment. The passages lead to a directing or reversing valve by which steam can
be supplied to either passage whilst the other is opened to the exhaust accord-
ing to the direction in which the engine is to be driven. Steam is supplied to
this directing valve through a second cylindrical valve which is geared to and
revolves with the other revolving shafts, and is so formed as to cut off the steam
supply to either division of the engine at the time when the radial piston of
that division is passing the abutment which works with it.
One reversing valve and one rotating cut off valve serve for both divisions of
the engine.
The cut off valve is cylindrical and hollow-a portion of its circumference is
exposed to steam in a steam space along one side of it. It has two opposite
ports in its side one near each end. Steam passes to the interior of the valve
through one of the ports in its side and through the other port passes to one or
other end of the directing or reversing valve to be directed by it either to the
channel leading to one side of the abutment or the other of one of the divisions.
Similarly when the cut off valve has made a half turn steam is directed to the
other division.
in
The directing or reversing valve is also cylindrical and hollow with ports
its side and inclined partitious by which when the valve is turned into one

page_text: position steam is directed to one or other of the channels leading to the annular
channels whilst the other is opened to the exhaust.
Similar cut off and directing or reversing valves can be used with undupli-
cated single engines.
T
D. CARTER.
C. J. SMITH.
improvements in Rotary Engines, applicable also as Pumps.
We, DAVID CARTER, Engineer, of 6, Ashtree Road, Stirchley, near Birming-
ham, and CHARLES JOHN SMITH, Carriage Builder, of Godalming, in the County
of Surrey, 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:-
;--
This invention relates to rotary engines of that class in which two cylinders
on parallel shafts are geared together the circumference of one cylinder being
in contact with the other for the greater part of their revolution and in which
one cylinder has a radial piston extending from it at one part of its circum-
ference and the other (which forms a rotating abutment) has a recess in its
circumference which allows the piston to pass as the cylinders revolve--and in
which also a cylindrical casing surrounds the rotating cylinders the piston on
the one cylinder fitting to the interior of one portion of the casing and the
remainder of the casing fitting around the cylindrical abutment.
According to this invention two such engines are formed together end to end.
The cylinders which carry the pistons are upon one shaft which extends through
both the cylindrical abutments are upon another shaft which also extends
through both and the piston of one division of the engine is set on the opposite
side of the shaft to the piston of the other division so that when one piston is
passing the abutment which works with it the other has upon it a full pressure
of steam.
For admitting steam to and allowing it to pass from the annular space around
which the radial piston of each division travels two passages are formed opening
into the annular space of that division on either side of and close to the abut-
ment. The passages lead to a directing or reversing valve by which steam can
be supplied to either passage whilst the other is opened to the exhaust accord-
ing to the direction in which the engine is to be driven. Steam is supplied to
this directing valve through a second cylindrical valve which is geared to and
revolves with the other revolving shafts, and is so formed as to cut off the steam
supply to either division of the engine at the time when the radial piston of
that division is passing the abutment which works with it.
One reversing valve and one rotating cut off valve serve for both divisions of
the engine.
The cut off valve is cylindrical and hollow a portion of its circumference is
exposed to steam in a steam space along one side of it. It has two opposite
ports in its sides one near each end. Steam passes to the interior of the valve
through one of the ports in its side and through the other port passes to one or
other end of the directing or reversing valve to be directed by it either to the
channel leading to one side of the abutment or the other of one of the divisions.
Similarly when the cut off valve has made a half turn steam is directed to the
other division.
The directing or reversing valve is also cylindrical and hollow with ports in

page_text: its side and inclined partitions by which when the valve is turned into one
position steam is directed to one or other of the channels leading to the annular
channels whilst the other is opened to the exhaust.
Similar cut off and directing or reversing valves can be used with undupli-
cated single engines.
The above improvements are shewn in the drawings annexed.
Figure 1 is a side elevation of the engine, Figure 2 is a vertical transverse
section through one division of the engine. Figure 3 is a horizontal section
through the valves. Figure 4 is a modification of the engine in which the two
valves are placed one above the other in place of side by side.
AA are two portions of a cylinder on a shaft A2-each portion carries a radial
piston A³ the piston carried by the portion A being on the opposite side of the
shaft to the piston carried by the other portion A¹.
BB are the cylindrical abutments on the shaft B². C is a casing enclosing
the piston carrying cylinder and cylindrical abutment of each division of the
engine. D is the reversing valve and E the continuously revolving valve for
controlling the admission of steam first to one division of the engine and then
to the other. The spindle of this valve and the shafts A2 B2 are all geared
together by gear wheels F so that they revolve at the same speed. GG are
passages leading from opposite sides of the casing of the valve D to the interior
of the portion of the casing surrounding the cylinders A A' and opening into
these portions of the casing on opposite sides of the cylindrical abutments.
There is one pair of such passages for each division of the engine.
His an
exhaust passage extending from the centre of the valve casing and serving for
both divisions of the engine. II are steam admission ports in the valve casing.
Steam is supplied alternately first to one and then to the other by the con-:
tinuously revolving valve E. Packing rings may be placed around the central
portions of the abutments BB and cylinders AA' as indicated by dotted lines
in Figure 1.
The valve D is cylindrical-it has ports or openings formed through it corre-
sponding with the ends of the passages G and ports or openings at each end
corresponding with the ports I and other ports or openings corresponding with
the exhaust passage H. JJ are inclined partitions placed across the interior of
the valve D.
When the valve is in the position shewn in Figure 3 steam entering by one
admission port I passes to one passage G belonging to one division of the
engine whilst the other passage G belonging to this division is open to the exhaust
passage H and the engine would be driven in one direction but if a half turn
is given to the valve the passage G which was before open to the steam supply
will now be open to the exhaust and the one which was open to the exhaust will
be open to the steam supply and the engine will be driven in the opposite
direction.
The steam admission valve E is cylindrical and closed at its ends, it has two
ports E formed through its sides one near each end and on opposite sides of its
axis and one capable of being brought to correspond with one port I and the
other with the other port I.
The casing which surrounds the valve E is so formed that a steam space is
left between it and the outer side of the valve. When one of the ports E' in
the valve is open to the steam in this space steam passes through the valve and
through the other port E to one division of the engine and when the valve has
made a half turn steam is similarly supplied to the other division of the engine.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that
what we claim is:-
1. The construction of rotary engines substantially as herein before described
and illustrated in the drawings annexed.

page_text: 2. In a double rotary engine, each of the two divisions of which has two pas-
sages leading to it, one for admission of steam and the other for exhaust, the
combination of the steam chest, the valve seat within it in the form of a seg-
ment of a cylinder, the hollow revolving cylindrical valve fitting to the seat,
the two steam ports in the valve seat one near each end, the hollow cylindrical
reversing valve with two inclined divisions across its interior and ports in its
sides by which when this valve is turned into one portion the two steam ports
in the seat of the steam admission are put into communication with one of the
passages leading to each division, whilst the other passages are put into commu-
nication with the exhaust, and the engine is driven in one direction, and when
the reversing valve has had a half turn given to it the passages which were
before supplied with steam are put into communication with the exhaust and
those which were in communication with the exhaust are supplied with steam,
and the engine is driven in the opposite direction.
3. In valve mechanism for supplying steam alternately to the two divisions
of a double rotary engine the combination of a steam chest, a valve seat in the
form of a segment of a cylinder within the steam chest, an outlet port formed
through the valve seat near each end one leading to the interior of one division
of the engine and the other to the other--a revolving hollow cylindrical valve
fitting to the seat and having a port formed through it near each end which can
be brought opposite to the corresponding port in the valve seat and the port at
one end being on the opposite side of the cylinder to the port at the other end
so that as the valve rotates steam passes first to one division of the engine and
then to the other.
4. Cut off and directing or reversing valves for rotary engines constructed
substantially as hereinbefore described.
Dated this 26th day of April 1900
D. CARTER.
C. J. SMITH.