An Improved Rotary Pressure Engine.
Year: 1898

page_text: An Improved Rotary Pressure Engine.
SAMUEL ARTHUR EINEM HICKSON, of Fulford, in the County of York, a Major
in the Royal Engineers, do hereby declare the nature of this invention to be as
follows:-
My invention relates to an improved motor which may be actuated by liquids
or gases under pressure that is to say by water, steam, compressed air carbonic
acid, or by the explosion of coal or other gases or explosives or other like forces.
In my invention the said steam or the like is used to obtain motion in a shaft
by its pressure between a moveable crank or crosshead revolving in a circular
chamber-co centric with shaft--and two sliding abutments. That is to say the
steam or other motive power is made to enter and expand alternatively first
between one abutment and the crank and then between the other abutment and
the crank the shaft revolving with the crank.
A circular metal ring or wheel to which this crank or crosshead is fixed closes
and revolves in, one side of the circular chamber, and the crank is further geared
by eccentrics to the two abutments in such a manner that when the other abut-
ment closes the chamber and through its valves on the one side admits and on the
other side exhausts the steam liquid or gas--the other abutment withdraws clos-
ing its valves, cutting off steam and allowing the crank or crosshead to pass.
This reciprocating motion between the abutments and crank is imparted by
connecting the shaft and crank with eccentrics fixed to and rotating with the shaft
and having two arms or connecting rods one of which is attached to the end of
either abutment.
I prefer broadly to construct my machine as follows. I make two castings con-
taining the circular chamber with its steam ports, and the horizontal slot in which
the abutments move.
The ring or wheel with the crosshead fixed to it is enclosed within these two
castings. The whole is then screwed together, the shaft passing through the
centre with the excentries fixed to it just where it emerges from the castings.
To reduce friction the abutments may further be constructed as piston valves
actuated by an excentric on the shaft.
It will be seen that in my machine I treat steam much in the same way as the
motive power of a clock, the abutments forming the escapement.
All the chief objections to the ordinary piston and rod are thus eliminated, more
especially the dead point whilst there is no need for cushioning. At the same
time increased power, speed and economy are secured.
Dated this 29th day of December 1898
SM. HICKSON,
Major, R.E.

page_text: I, SAMUEL ARTHUR EINEM HICKSON, Major, Royal Engineers, of Ash Villa,
Fulford, in the County of York, 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 an improvel rotary engine or motor which may he
driven by fluid pressure, such as steam, or may be used as an explosion engine,
or driven by gas compressed by mechanical means.
In carrying out this invention the cylinder of the engine comprises an annular
chamber which may be formed within a casting, one side of the casting being
open. This open side of the casting is closed by a disc, hereinafter called the
crank disc, carried fast upon the engine shaft which passes through the casting
within which the annular chamber is formed, being arranged concentric with the
said chamber, the disc is provided with a crank pin or piston which is made to
accurately fit the chamber or cylinder within which it travels carrying with it
the crank disc to which it is attached. The crank pin or piston is propelled by
admitting steam, for instance, on one side of it whilst all pressure is removed
from the opposite side. To effect this one or more sliding buttons are provided
which are alternately projected across the cylinder behind the piston, the steam
being admitted between any one such abutment and the piston so that the piston
is propelled forward in the chamber, an exhaust being opened on that side of the
abutment towards which the piston is travelling. As the piston nears the abut-
ment, which now projects across its path, the abutment is withdrawn, being
replaced after the piston has passed that point.
To avoid a dead centre two abutments are preferably used which alternately
project across, and are withdrawn from, the annular chamber or cylinder, and to
avoid end thrust on the crank disc and its shaft two chambers may be arranged
one on either side of the disc. The disc is in this case provided with two pistons,
the other parts of the machine being duplicated. Slide valves may be used to
regulate the admission of steam to the annular chamber or cylinder and also to
exhaust, or the abutments may themselves be used as slide valves for this purpose
and they may be reciprocated either mechanically or by steam or other pressure.
In the accompanying drawings which illustrate one method of carrying out this
invention more particularly in view of the engine being driven by steam:
Figure 1 is a side elevation of the engine,
Figure 2 is a horizontal section of Figure 1 on the line 2-2,
Figure 3 is a vertical section of Figure 2 on the line 3-3, and
Figure 4 is a transverse central section of Figure 3 viewed as indicated by an
arrow.
Like letters indicate like parts throughout the drawings.
The engine framing or casing comprises two castings A having each an annular
chamber B. The chamber B in each case is accurately bored, a core A' which is
part of the casting A being left in its centre; the castings A are each provided
with lugs A with which they may be bolted together so that the two chambers B
form one common chamber, which, however, is divided again into two separate
chambers by a crank disc C carried by its shaft C¹. The shaft C¹ passes through
both of the castings A being carried in suitable bearings in the same, and projects
beyond the outside of each; the crank disc C carries on either side of it a crank
pin or piston C2 which is made to exactly fit the chamber B. In each chamber
in a horizontal plane passing through the axis of the shaft C' are arranged two

page_text: sliding abutments 1) one on either side of the shaft which when in their forward
position project across the chamber 13 and enter slots or ways D₁ in the core A¹
of the casting A. These abutments D are made to exactly fit the chamber B, so
that when one abutment is closed its chamber is divided into two steam-tight com-
partments each limited by the abutment and the piston or crank pin C² respec-
tively. The abutments are each provided with an extension 11*, those on one
side of the shaft being connected together by a cross head 12, those on the other
side being similarly connected by a cross-head D³. The cross-heads are carried
in guides which may be of any convenient construction and secured in any
well-known manner to the castings A; also the abutments 1) have tenons on
their outer edges which run in grooves in the faces of the castings A and serve
to guide the abutments in their reciprocation across the chambers B.
on the other
The ends of the cross heads D2 D3 are provided with journals D whereby they
are connected by connecting rods 16 to double eccentrics D on the engine
shaft C. By this means as the shaft C₁revolves the abutments on
one side of the shaft are made to advance, whilst those
simultaneously retire. Within each casting are formed ports each of which com-
municates with one of the chambers B, the ports E being arranged
to admit live steam to the cylinder or chamber B, whilst the ports
are connected with the exhaust. The faces of the abutments I) are recessed at 18
so that when either abutment is in the forward position the ports EE are in
free communication with the chamber B, the steam and exhaust ports being thus
both open whilst both are again immediately closed as the abutment is withdrawn.
Within the core A¹ a balance chamber A3 is formed around the shaft and com-
municates with the slots or ways D¹, so that the same pressure is maintained upon
the ends of the abutment on the right as upon those on the left of the shaft. To
prevent steam from the balance chamber A escaping between the shaft C and its
bearings in the castings A stuffing boxes and glands of any well known con-
struction may be provided all though none such are shown in the drawings.
To regulate the admission of steam to the ports E and to control the exhaust El
they may be brought together at the top and bottom of the engine and enclosed
by a steam box F, the steam box F' communicates with a steam pipe F, and
within it is arranged in the usual well-known manner a slide_valve f. In the
particular construction shown in the drawings the slide valves are not regularly
reciprocated, but are controlled by any convenient mechanism, such as a worm
and worm wheel device G whereby they may be either made to open or close the
admission ports relatively to the exhaust ports; or in case of it being required
to reverse the direction of the engine the ports E may be converted into exhaust
ports, while those marked E may be made the admission ports.
The operation of the engine is as follows:-
Steam being admitted by the port E, as indicated by the arrow in Figure 3.
it is unable to escape from between the abutment on the right of the shaft and
the crank pin or piston C, both of which are made to be steam-tight fittings
within the chamber 13, so that the abutment being immovable the piston C³is pro-
pelled forward expelling any steam which is in the front of it by the exhaust E¹.
On, however, approaching the abutment which projects across its path the eccen-
tric D, which is carried on the shaft C, withdraws the said abutment by means
of its cross-head 2 and connecting rod 16 and at the same time projects the
abutment on the left across the chamber B and into the core A by means of its
cross-head 1). The ports on the right of the engine are thus closed while those
on the left are open. By this means steam is again admitted behind the piston
whilst an exhaust is opened on that side towards which the piston is travelling,
therefore the piston continues its motion in the same direction as before. As the
abutments on one side of the shaft are connected to the cross-head D2 and those
on the other side to the cross-head D³ it is obvious that the operations in each
chamber B will take place at the same time, so that an equal pressure will be
maintained upon either side of the crank disc C.

page_text: It will be understood that the engine described above may be considerably
modified, for instance, in place of using two chambers B one only may be used,
a thrust bearing being provided for the shaft C to take the pressure of the steam
against the side of the disc C; also should it be desired to reduce vibration the
crank pin or piston on one side of the disc may be placed on the opposite side
of the shaft to that on the other side of the disc, the abutments being then so
operated that whilst one is approaching the shaft the other on the same side is
retiring from it and vice versa, or the crank on one side may be set at any desired
angle relatively to that on the other side according to different requirements,
thrust bearings being introduced when necessary.
Further in place of the abutments D acting as slide valves, the ports EEI may
communicate direct with the chamber B, the slide valves 12 being, in this case,
regularly reciprocated by any well-known means the arrangement of the ports
being adapted to circumstances. Again the invention may be modified by pro-
viding the abutments D) with slide valves H reciprocated by means of valve
rods H engaging with eccentrics H2 mounted on the shaft C. These valves H
when arranged as shown in the drawings serve only as auxiliary valves for
exhausting any steam which creeping round the abutments D) may collect at
their rear.
This steam is made use of as the abutment comes forward the slide
valve being then in such a position that the port is closed whilst as the abutment
returns the slide valve opens the port and the steam is exhausted. If preferred,
however, each of the slide valves H may be provided with two ports and the
abutments provided, with a head or piston so that steam may be admitted first on
one side and then on the other side of each head or piston thus operating the abut-
ments without the aid of the eccentric rods De and eccentrics D. When the
abutments are reciprocated by this means the steam is preferably admitted direct
to the annular chamber or cylinder B by the slide valve F2 as described above.
To prevent leakage of steam between the wall of the chamber and the outer
circumference of the crank disc C, the latter may be provided with a packing
ring of any well known construction; also for the same purpose the crank pin C³
may comprise a central pin fixed to the disc C and surrounded by two approxi-
mately semicircular portions provided with packing between the two respective
parts in any well known manner.
Having now particularly described and ascertained the nature of my sail
invention and in what manner the same is to be performed, I declare that what
I claim is
1. In a rotary engine the combination with an annular chamber or cylinder
within which revolves a crank pin or piston of one or more abutments which
slide across the path of the piston and divide the chamber at stated intervals sub-
stantially as and for the purpose described.
2. In a rotary engine the combination with an annular chamber or cylinder
closed on one side by a crank disc which carries a crank pin or piston arranged
within the chamber of one or more sliding abutments which serve as slide valves
operating substantially as and for the purpose described.
3. In a rotary engine the combination with an annular chamber having an
inner core A¹ with or without a balance chamber A3 of a crank disc C with its
pin or piston C and one or more reciprocating abutments arranged to slide across
the chamber and enter the core serving or not as slide valves substantially as and
for the purpose described.
4. In a rotary engine the combination with ene or more sliding abutments D
of one or more slide valves FF2 which may be arranged as regulating, operating
or reversing valves substantially as described.
5. In a rotary engine the combination with one or more sliding abutments D
of slide valves H substantially as and for the purposes described.
6. In a rotary engine the combination with an annular chamber B divided by a
crank disc C having a double crank pin or piston C² which operates in conjunction

page_text: with sliding abutments D with or without the aid of valves FF2 or H substan-
tially as described.
7. The complete rotary engine substantially as described or illustrated in the
accompanying drawings.
Dated this 28th day of August 1899
BOULT & WADE,
Agents for the Applicant.