An Improved Rotary Engine.
Year: 1892

page_text: Date of Application, 25th Apr., 1892
Complete Specification Left, 31st Jan., 1893-Accepted, 22nd Apr., 1893
PROVISIONAL SPECIFICATION.
An Improved Rotary Engine.
We HARRY WILLIAMS, of 134 Somerset Street, Richmond, in the Colony of
Victoria, Engineer, and THOMAS LANGSTON FISHER, of Spring Villa, Lennox
Street, Hawthorn, in the colony aforesaid, Mechanic, do hereby declare the nature
of this invention to be as follows:-
Our present object is to provide a rotary engine in which→
Firstly-The form or shape of the cylinder and the arrangement of a piston
with a drum will admit, during the expansive working of one induction of steam,
of a second induction prior to the opening of the exhaust.
Secondly-The arrangement of the piston will permit it to be quickly increased
and diminished in area so that the maximum degree of work may be obtained from
the steam before it exhausts from the engine.
Thirdly The construction and arrangement of said piston and its drum so
that both ends of the former will be in constant contact with the bore of the engine
cylinder.
Fourthly:-The arrangement of the drum eccentrically within the cylinder
whereby the piston may have a considerable leverage and an equal balance
during each revolution. The following is a brief outline of the combination
and arrangement of the parts of our engine. It consists of a cylinder having its
steam inlet situated at right angles to the exhaust which lies in a vertical direction.
The cylinder is provided with two end covers and has a peculiarly formed bore
within which is eccentrically arranged a drum. The circumference of said drum
touches the bore surface of the cylinder and in order to take up the circumferential
wear, there is a gunmetal strip provided with a steel spring which is conveniently
sealed in a recess formed in the cylinder body. Two discs form the end of said
drum so that the latter may carry a piston which slides inwardly and outwardly at
right angles to its axis and whilst working rotates the drum. For the purpose of
rendering the piston steam tight within the drum there are two metal springs and
strips arranged longitudinally and in contact with the engine shaft. The ends of
the piston are fitted with suitably hinged or jointed blocks or plates which adapt
themselves to the bore of the aforesaid cylinder.
Within the said drum there are arranged four anti-friction rollers between each
pair of which slides the aforesaid piston. The arrangement of the piston is such
that it forms two pressure chambers during each revolution of the beforementioned
drum. Each of said chambers becomes of a greater area as the piston moves
around to the vertical diametrical line of the cylinder to permit of the expansion
and exhaustion of steam. The two sides of the piston are fitted each with a steel
strip and a spring to effect a steam tight joint between the piston and the end covers
of the cylinder.
The steam is admitted to the cylinder by means of a rotary valve which is fitted
to work in a chest cast with or secured to the cylinder aforesaid. This valve is
operated by a rod to which a reciprocating motion is imparted by means of a disc
crank secured to the shaft of the engine. This shaft is divided into two parts by
the interposition of the aforesaid drum. The cylinder previously referred to is
lined out by drawing two lines across its roughly cast bore to form four right angles
the bisecting point of which serves as a centre for the purpose of scribing the piston
for the drum.
A certain length of the piston is then determined upon and a horizontal line is
drawn through the centre of the drum and across the cylinder to represent the

page_text: piston. At two points namely one near each end of said piston line we strike an
arc which touches the top of the drum and also the two ends of the piston line.
Whatever may be the desired size of the drum or the length of the piston the
bore contour with the exception of the arc portion can be obtained by following
said arc with one end of a template piston and scribing the contour by means of
the other end of said template. The foregoing method of lining out the bore of the
cylinder permits of either the size of the drum or the length of the piston to be
varied. The longer the piston when used with a drum of a certain size so
there will be a lesser depth of arc; the shorter the piston is made without
altering the size of the drum, the cylinder will be nearer the form of a circle.
The arrangement of the parts permits of the engine being easily converted
into either a pump or a blower or a reversing engine. When the engine
is to be used as a pump, a shorter piston would be required to gain the leverage
on the drum, but when used as a blower the blocks or plates jointed to the ends of
the piston would be replaced by rollers carried by suitable joints whilst for a
reversing engine suitable gear, consisting of two slide valves would be arranged in
conjunction with a dead plate situated between the main valves and the cylinder
and coupled direct with the governors.
Dated this 25th day of April 1892
W. P. THOMPSON & BOULT,
Agents for the Applicants.
COMPLETE SPECIFICATION.
An Improved Rotary Engine.
We, HARRY WILLIAMS, of 134 Somerset Street, Richmond, in the Colony of
Victoria, Engineer and THOMAS LANGSTON FISHER, of Lennox Street,
Hawthorn, in the Colony of Victoria, Mechanic, 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 :—
Our present object is to provide a rotary engine in which,-
Firstly: The form or shape of the cylinder and the arrangement of a piston
with a drum will admit, during the expansive working of one induction of steam,
of a second induction prior to the opening of the exhaust.
Secondly-The arrangement of the piston will permit of two pressure chambers
to be quickly increased and diminished in capacity so that the maximum degree
of work may be obtained from the steam before it exhausts from the engine.
Thirdly: The construction and arrangement of said piston and its drum so
that both ends of the former will be in constant contact with the bore of the engine
cylinder.
Fourthly:-The arrangement of the drum eccentrically within the cylinder
whereby the piston may have a considerable leverage and an equal balance during
each revolution.
But in order that our invention may be better understood we will now refer to
the accompanying sheet of drawings.
Figure 1 is an end elevation of our engine.
Figure 2 is an end vertical section through the cylinder, sliding piston, piston
drum, and an oscillating steam valve.
Figure 3 is a side vertical section through Figure 1.
Figure 4 is a side elevation of the sliding piston which is shewn partly in
section.
Figure 5 represents a full end elevation of the sliding piston shewn at Figure 4.
Figure 6 is a side elevation of the flat sliding piston without the hinged blocks
and intermediate pieces at each end.
Figure 7 is an end elevation of the piston shewn at Figure 6.

page_text: Figure 8 is a sectional plan of piston shewing its sides and also the front and
rear faces provided with steam-tight gun metal strips and steel springs.
Figures 9 and 10 are elevations of the intermediate pieces which are fitted to
each end of the sliding piston to carry the hinged blocks.
Figure 11 represents an end elevation of one of said intermediate pieces of the
sliding piston.
Figure 12 is an end elevation of one of the blocks hinged upon the intermediate
piece of the sliding piston.
Figure 13 is an end elevation of the piston drum illustrating the bearings which
carry the antifriction rollers.
Figure 14 is an end section of the piston drum and antifriction rollers, and
Figure 15 represents a sectional elevation of Figure 14.
Figure 16 a diagram illustrating the various points from which is lined out the
contour of the cylinder bore.
The drawings are prepared to a scale of two inches which equal one foot.
Like letters of reference represent like parts in all the views.
In the drawings A is the cylinder carried by a suitable bed B. C is the steam
inlet communicating with the passage D.
Said inlet C is situated at right angles to the exhaust D'.
With said exhaust D 'communicates the passage D'. The cylinder aforesaid is
provided with two end covers E and F which are secured to the faced cylinder
ends by means of a suitable number of stud bolts similar to G. H and H are
two shaft glands fitted upon the covers E and F to prevent any leakage of water
or steam which may at any time occur through the cylinder. The cylinder afore-
said has a peculiarly formed borc (as hereinafter described) within which is
eccentrically arranged a drum termed "the piston drum." J and J are two shafts
between which is interposed the piston drum hereinafter described. K is the
piston which slides inwardly and outwardly at right angles to the axis of said
drum.
Lis the gun metal strip arranged in a longitudinal channel formed in the
cylinder A as shewn at Figures 2, and 3. M and M represent two steel springs
seated in two recesses formed above the longitudinal recess which contains the
transverse strip L. Said strip forms a joint to prevent the steam passing between
the contact surfaces of the drum and the cylinder. M¹ and M' are two piston
rings sprung in grooves formed in the circumference of the piston drum as
illustrated in Figures 3, and 15.
M² and M² are similar rings sprung into the before described cylinder covers E
and F as at Figure 3. N represents the blocks which are hinged one to each end
of the piston body as at Figures 2, 3, 10 and 12. Each block is made with two
tubular eyes P and P which carry a pin similar to O. A space is left between
said eyes to receive the tongue R projected from the intermediate piece as shewn
in Figures 9 and 10. This tongue R also forms shoulders upon the intermediate
piece Q to fit into the cross shaped gulleted ends of the flat piston body K.
In each end of said piston body K are formed three recesses in which are arranged
three spiral springs similar to R', R' and R³, for the purpose of keeping the hinged
blocks N steam-tight with the contour of the cylinder. S represents the piston
drum to the ends of which are bolted the flanged discs T and T suitably secured to
the shafts J and J. Said discs and piston drum S are secured together by means of
four stud bolts similar to T' as in Figure 3. U and U are two dowels formed upon the
inner faces of the flanges or discs T to project into the cylindrical recesses provided
one in each end of the piston drum, and bear_upon the springs X hereinafter
described as at Figure 3 and between each disc T and the shaft bearings are placed
the collars V and V. Within suitable recesses formed in the drum shewn at
Figures 2, 13 14 and 15 there are arranged four antifriction rollers similar to Y
between each pair of which slides the aforesaid piston K. Said rollers are made
hollow and their ends are reduced to work in metal bearings or bushes suitably
secured in the piston drum.

page_text: For the purpose of rendering the sliding piston K steam-tight within the drum S
there are four metal strips similar to W and W arranged around the piston K as
shewn at Figures 2, 3, and 8. Each of said strips is made in the form of a right
angle and they are laid in two rows. The ends of each strip are cut at any suit-
able angle and at the four connecting points of said ends we provide corner pieces
similar to W' as represented in Figure 8.
Said strips W are seated or otherwise fitted into recesses or channels similar
to U' formed in the metal part of the piston drum S as illustrated at Figures 14
and 15.
Said strips engage the front and rear faces as also the sides of the piston K and
in order to press said strips W against the faces and sides there are springs similar
to X arranged two for each of said faces and sides of the piston as shewn at
Figure 8. Z and Z are two metal strips fitted one in each of the recessed sides of
the piston K. The ends of said strips engage the eyes P of the hinged blocks N.
Three steel springs similar to Z' are arranged in recesses formed in the ends of the
piston drum to press the strips Z against the inner faces of the drum so as to effect
a steam tight joint. a is a steam chest cast with or secured to the cylinder A.
Within said chest is arranged the oscillating or semi-rotary valve 6 of any well
known class. This valve is operated by a rod c jointed to an arm on shaft f to
which rod a reciprocating motion is imparted by means of the eccentric d secured
to the shaft J. e is a door attached to said chest a. f is a horizontal shaft
carried by the two bearings g, h, is a steam tight gland for the chest a.
The
following method is adopted in order to obtain the bore contour of the cylinder,
which contour is illustrated at Figure 16.
We take the cylinder and line out the contour by drawing two straight
lines A B C D forming four right angles and intersecting each other at E.
From E as centre we describe a circle equal to the determined diameter of the
drum F, G, H, I, then upon the line A, B, and from point E as a centre we set
off the point K L equal to the length of piston determined upon.
An arc is then described intersecting K, G, L, then with a proper template of
piston drum and rollers (the template drum working on centre B with one end of
said template piston following the arc KG L) we describe the differential
curve L M K with the other end of said template piston to complete the contour.
The foregoing method of lining out the bore of the cylinder permits of the size
of the drum or the length of the piston being varied.
The longer the piston when used with a drum of a given size, so there will
be relatively a lesser depth of arc L M K, the shorter the piston is made without
altering the size of the drum the cylinder will be nearer the form of a circle.
The boring of said cylinder is effected by means of a cam arranged upon a
spindle centred in a boring lathe.
Said cam has a contour which corresponds with the bore of the cylinder but its
size is less by one half.
The boring lathe employed carries a compound slide and a face plate to which the
cylinder is attached in an ordinary manner.
.
In order to bore said cylinder the screw of the upper slide is removed so that
it may be operated and be controlled by means of a metal bar hereinafter
described.
The lock nut of the leading screw is placed in the latter so as to rigidly secure
the saddle or base slide way upon the lathe shears.
To said saddle or base slide way of the lathe is affixed a vertical bracket which
is of a greater height than the tool rest. One end of the aforesaid straight metal
bar is pivoted to the upper end of said bracket whilst the other end of the bar is
jointed to the slide bed carrying the tooth rest.
Said bar is arranged to bear upon the surface of the cam so that when the latter
is rotated said bar will impart an inward and outward movement to the slide rest
and boring tool which movement corresponds with the bore contour to be cut or
formed in the cylinder.

page_text: The principal parts of our invention operate as follows,-
When live steam is admitted through the inlet C and valve 6 it passes through
the passage D thence into the cylinder A. After the piston passes the inner end
of said inlet D a pressure chamber is at once formed between the drum S and the
rear face of the piston. As the latter reaches the exhaust D' its upper end passes
the inlet D and forms a second pressure chamber. The expanded steam in the
first pressure chamber then escapes through the exhaust D¹ and any steam that
may not have escaped will be cushioned after the piston passes the said exhaust ;
this cushioned steam will escape through the passage D' and pass through the
exhaust D'. As the piston K revolves it rotates the drum S which is kept steam-
tight with the cylinder by means of the strip L and as it slides inwardly and
outwardly the four rollers Y reduce friction thereof to a minimum, whilst the
various springs serve to render the piston K steamtight within the piston drum S.
It will now be seen that the arrangement of the piston is such that it forms two
pressure chambers during each revolution of the before mentioned drum, and,
further that each of the said chambers becomes of a greater capacity as the piston
moves around to the vertical diametral line of the cylinder to permit of the expansion
and exhaustion of steam.
It may be here explained that we construct the cylinder A, rollers Y, and
intermediate pieces Q, of cast iron, piston K of cast steel, and the hinged blocks N
and bearings of the rollers of gunmetal.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is
:
Firstly A cylinder having a bore contour formed in the manner hereinbefore
described and the steam inlet C and D and exhaust passages D' and D² situated
so that the piston will admit, during the expansive working of one induction of
steam of a second induction prior to the opening of the exhaust D'.
Secondly: In a rotary engine the combination with a drum S of a piston K
arranged to slide through the axis of said drum, substantially as hereinbefore
described and as illustrated in our drawings.
Thirdly: The combination with the piston K of a steam tight band W and W,
and four antifriction rollers seated in recesses formed in the piston drum S,
substantially as hereinbefore described, and as illustrated in our drawings.
Fourthly: In a rotary steam engine a piston K constructed with ends consisting
of intermediate pieces Q springs RR' and R2 and the hinged blocks N, substantially
as hereinbefore described and as illustrated in the accompanying drawings.
Dated this 30th day of January 1893.
W. P. THOMPSON & BOULT,
Agents for the Applicants.