Year: 1887

page_text: Date of Application, 7th Nov., 1887
Complete Specification Left, 2nd Aug., 1888
Complete Specification Accepted, 7th Sept., 1888
We WILLIAM TOMKINS STURGESS and EDWARD TOWLSON both of Saint Michael
at Coslany in the City of Norwich in the County of the same City Engineers do
hereby declare the nature of this invention to be as follows:-
In suitable Cylinders as shewn in the accompanying drawing are two fine pitched
genred wheels on each of which is a larger projection or tooth which are the pistons
of the engine and which the pressure on admission drives in opposite directions.
This larger projection or tooth "A" on each wheel is made to gear into a corre-
sponding recess "B" in the opposite wheel so that while the said projections are the
pistons proper the two wheels are free to revolve on their separate shafts while the
teeth being machine cut form a tight steam joint between the two wheels thus
preventing the steam or pressure from blowing through.
A
Metallic packing rings are provided for each end of both wheels and covers.
steam joint is also made between the outside of teeth and cylinders by metallic
packing so as to prevent all leakage of steam or pressure.
Having by these arrangements made a perfectly tight rotating piston a cut off
expansive valve "C" is applied for the expansive use of steam, or gases, worked by
short stroke eccentric "D."
Dated this Sawanth day of Novambor 1887
WILLIAM TOMKINS STURGESS.
EDWARD TOWLSON.

page_text: An improved Rotary Expansive Steam Engine or Pump.
WO WILLIAM TOMKINS STURGESS and EDWARD TOWLSON, both of Saint Michaels
at Coslany, in the City of Norwich, in the County of the same City, Engineers 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 has reference to improvements in the construction of rotary engines
wherein the motive fluid can be used expansively.
In a rotary engine according to this invention two wheels or hubs, each provided
with a single tooth or projection to serve as a piston, and with a recess to permit the
tooth or projection of the other to pass, are mounted to rotate in opposite directions in
a pair of cylinders or chambers provided with supply and exhaust ports, the said
wheels or hubs being caused to rotate in unison by toothed gear that serves also to
prevent escape of fluid between the wheels or hubs. Metallic packing forms a fluid
tight joint between the ends of the said wheels or hubs and the covers, and between
the peripheries of the pistons and the interiors of the cylinders or chambers in which
they work.
An expansion valve worked by an eccentric enables motive fluid to be used
expansively.
Apparatus according to this invention may be used as a pump, the expansion valve
being then dispensed with.
In the accompanying sheets of drawings which illustrate a rotary engine constructed
according to this invention:
Fig. 1 is a plan or top view, and
Fig. 2 a transverse section on the line A B Fig. 1.
Fig. 3 is a longitudinal section on the line C, D, Fig. 2, of one of the wheels or
hubs and adjacent parts of the cylinder or chamber in which it rotates.
1 and 2 are wheels or hubs geared together by fine pitched teeth 3 extending
almost entirely around the periphery of each; they are each provided with a single
tooth or projection 4 that serves as a piston and with a recess 5, so formed that the
two wheels or hubs may roll together. These wheels or hubs are each secured upon
a shaft 6 and mounted to revolve in opposite directions within a cylindrical chamber 7.
8 is an inlet port for motive fluid and 9 an exhaust port. The teeth 3 may be machine
cut in order that they may form a fluid tight joint between the wheels or hubs and
prevent the motive fluid passing direct from the supply port to the exhaust port
without operating the pistons, 10, 10 are split metal packing rings of conical form
externally and arranged within correspondingly formed recesses in the end covers 11
of the chambers 7; these rings in expanding are forced end wise (in consequence of
their conical formation) into close contact with the ends of the wheels or hubs which
are thus caused to make a.fluid tight joint with the end covers of the chambers.
Each piston 4 is formed with a recess into which are fitted two plates 12 cach
capable of slight radial and end wise movement. These plates 12 work in close contact
with the interior of the chamber 7 in which they revolve by centrifugal force. 13 is a
spring arranged between each pair of plates 12 for forcing them endways and making
a tight joint with the end covers. 14 is an expansion valve of oscillating cylindrical
type for cutting off the supply of motive fluid to the chambers 7 at any desired part
of the stroke or revolution of the engine. This valve, which is mounted to partly
rotate on a cylindrical seat 15 is formed with a port 16; it is operated by an

page_text: eccentric 17 which is secured to one of the shafts 6 and engages with a lever 14"
secured to the valve spindle as shewn in Figure 1. The point of cut off will depend
upon the position of the eccentric as well understood. The teeth 3 in addition to making
a fluid tight joint between the wheels or hubs may also serve to cause the said wheels
or hubs to rotate correctly together in unison so that the pistons shall pass each other.
In order however to relieve the teeth of the strain and consequent rapid wear that
would take place if used alone for the latter purpose it is preferred to also gear the
shafts together by external toothed wheels 18 as shewn in Fig. 1. 19, 19 are
driving pullies secured to the shafts 6; they may also serve as fly wheels. 20 is the
inlet pipe for motive fluid and 21. the outlet for exhaust fluid. When motive fluid is
admitted to the chambers 7 the wheels or hubs 1 and 2 are rotated in opposite
directions the motive fluid working expansively after further supply thereof has been
cut off, until the pistons open communication with the exhaust. The remainder of the
rotation of each wheel or hub is effected by the fly wheel or wheels.
When using the improved motor as a pump the wheels or hubs 1 and 2 are rotated
in opposite directions by external means; it may be by a similar apparatus acting as
a motor and driving direct. The expansion valve and the means for operating the
same are then dispensed with and the delivery and supply pipes may be provided with
suitable lift and delivery valves for controlling the passage of the fluid to be
pumped.
When the pistons are used for pumping fluids they displace the air in front of them
at starting and create a partial vacuum behind them into which the fluid to be
pumped flows; during the revolution this fluid is lifted or forced into the delivery
pipe being prevented from returning to the pump after the piston has passed the
outlet opening by a delivery valve. At each succeeding revolution fluid will be drawn
into and forced from the pump.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. A rotary engine or pump constructed with two wheels or hubs mounted and
geared to rotate in unison in opposite directions within cylindrical chambers and to
form a fluid tight joint between them, each such wheel or hub being provided with one
tooth or projection that serves as a piston and with a corresponding recess to admit of
the passage or rotation of the piston of the other wheel or hub substantially as
hereinbefore described and shown.
2. In a rotary engine or pump of the kind referred to in the preceding claim
providing the teeth or projections that serve as pistons with plates capable of limited
radial and end wise movement for preventing passage of fluid between the said pistons
and the internal surfaces of the chambers in which they rotate substantially as
hereinbefore described.
3. A rotary engine such as referred to in claim 1, provided with an expansion
valve having a fixed cut off substantially as herein before described for the purpose
specified.
4. The improved rotary engine constructed and operating as hereinbefore described
with reference to and shown in the drawings annexed.