Improvements in Rotary Engines.
Year: 1889

page_text: Date of Application, 26th Oct., 1889
Complete Specification Left, 26th July, 1890-Accepted, 30th Aug., 1890
PROVISIONAL SPECIFICATION.
Improvements in Rotary Engines.
We, ALEXANDER FRANCIS GARDEN BROWN of Swindridge Muir, Dalry in the
County of Ayr, Gentleman, and GEORGE ANDREW GRANT of Broad Street, Mile End
in the City of Glasgow, Cotton Spinner and Manufacturer, do hereby declare the nature
of this invention to be as follows:-
This invention has for its object improvements in the rotary engine for which
Letters Patent of the United Kingdom of Great Britain and Ireland have been
granted to Alexander Francis Garden Brown bearing date the 2nd day of
February 1888, No. 1555, and the improvements constituting the present invention
relate to the rotating piston G, to the exhaust in conjunction with the arms H,
and to improved arrangements or constructions of the said arms. Under the
present invention the piston instead of resting upon and rotating around glands E,
and having a crank arm F, keyed to the main shaft C, extending into a recess at
the interior is made with a hoss which is keyed direct to the said shaft C. The
packing strip a, extending across the breadth of the piston and the similar strips
extending down the ends of the piston are made in two pieces dovetailed or
rebatted into each other at the centre and at the said joints springs are inserted
the tendency of which is to force the two parts of the strips asunder so as to
ensure that notwithstanding tear and wear of the parts the strips shall always bear
steam tight against the interior of the cylinder. Under the strip a and within
the end strips a thin plate is situated the springs referred to in the said previous
specification bearing against the said plates. To obtain a quicker exhaust with arms
arranged and constructed as described in the Specification filed in pursuance of the
said Letters Patent, the exhaust passages through the said arms instead of communi-
cating directly with exhaust ports communicate with passages formed in the cylinder
casing and leading to the distributing valve casings from which ports conduct the
exhaust steam away from the engine. The distributing valve used may be an ordinary
slide, a piston, or an oscillating valve and in any case it is so arranged that previously
to or simultaneously with opening the steam port leading from the valve casing to the
recess in the cylinder at the back of the arm it uncovers the exhaust port and ensures
a quicker exhaust for the spent steam.
With the improved arrangement or construction of arms embraced by this invention
exhaust passages through the arms may be dispensed with the arms being solid
throughout. Under the improvement each arm has two horns or branches extending
in opposite directions from its boss, and in single acting engines a steam passage com-
municating with the distributing valve casing is made in the recess of the cylinder
behind one of the said branches as before whilst an exhaust passage is made at a part
of the cylinder which is covered by the end of the other branch of the arm when it is
not necessary that the said passage should be open for the exhaust of steam.
With this construction as the piston rotates and the horn or branch in front of one
steam passage is thrown out against it the other horn or branch of the said arm is
thrown back so as to uncover its exhaust passage whilst at the same time the piston

page_text: moves out the corresponding horn or branch of the other arm to cover its exhaust
port. In reversing engines steam admission and exhaust passages are provided as
described in conjunction with both horns or branches of each arm the arrangement in
either case having the effect of lessening or preventing shock and noise in working the
engine.
Under a modification the arms otherwise constructed as above described may have
exhaust passages through their bosses as in the previous Patent the exhaust passages
in the cylinder at the ends of the arms being in that case dispensed with and with
either modification to ensure that the arms shall only move at the proper times a bolt
is or may be provided in conjunction with the steam distributing horn of each arm the
said bolt being connected to a rocking lever so worked by a crank from the main shaft
as to be entered into and withdrawn from the point of the said horn or branch at the
required times or the bolts may be situated within the said distributing horns or
branches of the arms and furnished with springs whose tendency is to force them out-
wards into recesses in the cylinder the bolts being withdrawn when required by the
live steam admitted through the distributing valves acting on pistons formed on or
attached to the bolts; or the arms on opposite sides of the piston may be connected
together at their extremities by a link working either in a recess made in the inner
side of one end of the cylinder or situated outside the cylinder. The arms are carried
on spindles or studs which are packed steam tight in the cylinder ends.
Dated this Twenty-third day of October 1889.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.
COMPLETE SPECIFICATION (AMENDED).
Improvements in Rotary Engines.
We, ALEXANDER FRANCIS GARDEN BROWN, of Swindridge Muir, Dalry, in the
County of Ayr, Gentleman, and GEORGE ANDREW GRANT, of Broad Street, Mile End,
in the City of Glasgow, Cotton Spinner and Manufacturer, 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 for its object improvements in the rotary engine for which
Letters Patent of the United Kingdom of Great Britain and Ireland have been granted to
Alexander Francis Garden Brown bearing date the 2nd day of February 1888 No. 1555
and the improvements constituting the present invention relate to the rotating piston-G,
to the exhaust in conjunction with the arms H, and to improved-arrangements-or
constructions of the said arms. The present invention is illustrated by the several
figures on the accompanying drawings, figure 1 being an elevation with the end or
cover of the casing or cylinder removed and figure 2.a horizontal section on the line a-x
figure 1 of one arrangement. Figures 3 and 4 are respectively sections of modified
arrangements whilst figures 5, 6 and 7 are detailed views hereinafter more particularly
referred to. Under the invention The piston G, instead of resting upon and rotating
around glands E, and having a crank an arm F, keyed to the main shaft C, extending
into a recess at the interior is keyed direct to the said shaft C. The packing
strip a, extending across the breadth of the piston and the similar strips extending
down the ends of the piston are as seen at figures 5, 6, and 7, made in
two pieces dovetailed or rebatted into each other at the centre and at the
said joints springs a', are inserted the tendency of which is to force the two parts of
the strips asunder so as to ensure that notwithstanding tear and wear of the parts the
strips shall always bear steam tight against the interior of the cylinder and more
particularly in the corners. Under the strip a, and within the end strips a thin
plate b, is situated the springs referred to in the said previous specification bearing
against the said plates. With the arrangement shewn by figures 1 and 2, the arme

page_text: Aaps or abutments H, are constructed substantially as described in the Specification
filed in pursuance of the said Letters Patent and the exhaust passages d, through
the said arms flaps or abutments communicate directly with exhaust ports e, but
instead of this arrangement and to obtain a quicker exhaust the passages d, through
the arms flaps or abutments may be dispensed with and as seen at figure 3, the
exhaust may take place through passages e, formed in the cylinder casing and
leading to the distributing valve casings J, from which ports J, conduct the exhaust
steam away from the engine. The distributing valve used may be an ordinary slide,
a piston, or an oscillating valve and in any case it is so arranged that previously to or
simultaneously with opening the steam port J, leading from the valve casing to the
recess in the cylinder at the back of the arm abutment H, it uncovers the exhaust
passage e, and port J', and ensures a quicker exhaust for the spent steam.
Figure 4, illustrates an arrangement in which a modified construction of arms
abutments H, is employed and wherein in consequence of such construction exhaust
passages through the arms abutments may also be dispensed with the arms abutments
being solid throughout. Each arm abutment H, has two horns or branches extending
in opposite directions from its boss and in single acting engines a steam passage 1,
communicating with the distributing valve casing J, is made in the recess of the
cylinder behind one of the said branches as before whilst au exhaust passage 2, is
made at a part of the cylinder which is covered by the end of the other branch
of the arm when it is not necessary that the said passage should be open for the
exhaust of steam.
With this construction as the piston G, rotates and the horn or branch in front of
one steam passage 1, is thrown out against it the other horn or branch of the said arm
is thrown back so as to uncover its exhaust passage 2, whilst at the same time the
piston moves out the corresponding horn or branch of the other arm to cover its exhaust
port 2. In reversing engines steam admission and exhaust passages are provided as
described in conjunction with both horns or branches of each arm the arrangement
in either case having the effect of lessening or preventing shock and noise in working
the engine.
Under a modification the arms abutments otherwise constructed as above described
may have exhaust passages through their bosses as in the previous Patent the
exhaust passages in the cylinder at the ends of the arms abutments being in that
case dispensed with and with either modification to ensure that the arms abutments
shall only move at the proper times a bolt 3, is or may be provided in conjunction
with the steam distributing horn of each arm abutment the said bolt being connected
to a rocking lever 4 so worked by a crank or eccentric from the main shaft as to
be entered into and withdrawn from the point of the said horn or branch at the
required times.
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. In a rotary engine of the class set forth-keying the rotating piston C, direct
to the main shaft as described with reference to figures 1 and 2 of the annexed
drawings
2. In a rotary engine of the class set forth the improved packing for the rotating
piston substantially as described with reference to figures 5, 6 and 7 of the
accompanying drawings.
3. In a rotary engine of the class set forth the improved means for providing a
quick exhaust substantially as described with reference to figure 3 of the drawings
appended.
1. In a rotary engine of the class set forth the arrangement in combination with solid
abutments H of distributing valves and ports as described with reference to Figure 3.
42. In a rotary engine the combination of a rotating piston G, with double
branched oscillating arms abutments H, and with means for locking and unlocking

page_text: the said arms abutments so as to cause them to cover and uncover steam admission
and exhaust ports substantially as described with reference to figure 4 of the drawings
annexed.
Dated this Twenty-fifth day of July 1890.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.