IMPROVEMENTS IN OSCILLATING STEAM ENGINES
Year: 1867

page_text: LETTERS PATENT to Daniel Rankin, of the Firm of Rankin and Blackmore,
of Greenock, in the County of Renfrew, North Britain, Engineers and
Ironfounders, for the Invention of "IMPROVEMENTS IN OSCILLATING STEAM
ENGINES."
Sealed the 11th October 1867, and dated the 16th April 1867.
PROVISIONAL SPECIFICATION left by the said Daniel Rankin at the
Office of the Commissioners of Patents, with his Petition, on the 16th
April 1867.
I, DANIEL RANKIN, of the Firm of Rankin and Blackmore, of Greenock,
in the County of Renfrew, North Britain, Engineers and Ironfounders, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN OSCIL-
LATING STEAM ENGINES," to be as follows, that is to say :-
This Invention has for its objects to simplify the construction and render
more efficient the working of oscillating steam engines, and consists in novel
combinations of various parts.

page_text: In one modification each cylinder is fitted with two piston rods having one
eross bead, which is jointed on its inner side upon the crank pin, the bearing
brasses of the crank pin joint being tightened up by means of one or more
screws tapped through from the upper side and bearing on the upper block.
The screws are made tubular for the passage down them of lubricating matter
from cups formed or fitted on or connected to their upper ends. A simple
cut-off valve is applied outside the steam trunnion, whilst two slide valves are
adapted to the cylinder as close to the steam trunnion as possible in order to
reduce the passage between the cut-off valve and them, instead of such valves
being situated round at the other side as ordinarily. The eccentrics for
working these main slide valves are placed on the paddle or crank shaft
instead of the intermediate shaft.
In a second modification one or more of the herein-before described features
may or may not be used, but a single main slide valve is applied to the cylinder
just within the steam trunnion, and is actuated directly from one or more
eccentrics by means of a rod jointed to the buckle or valve frame or fastening
in or near the axis of oscillation of the cylinder, the oscillation being allowed
for by adapting to the buckle or frame a trunk working through a stuffing
box. By these arrangements a comparatively long stroke is more conveniently
obtained than in ordinary oscillating engines, whilst the valve gear is much
simplified; and when cut-off valves are used they are rendered more efficient
in action in consequence of the space between them and the main slide
valves being reduced to an extent which has hitherto only been attained or
approached by adapting complicated gear to work the cut-off valve on the
cylinder instead of outside the trunnion.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Daniel Rankin in the Great Seal Patent Office on the
15th October 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DANIEL
RANKIN, of the Firm of Rankin and Blackmore, of Greenock, in the County 3
of Renfrew, North Britain, Engineers and Ironfounders, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixteenth day of April, in the year of our Lord One
thousand eight hundred and sixty-seven, in the thirtieth year of Her reign,

page_text: did, for Herself, Her heirs and successors, give and grant unto me, the said
Daniel Rankin, Her special licence, that I, the said Daniel Rankin, my
executors, administrators, and assigns, or such others as I, the said Daniel
Rankin, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time, and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN OSCILLATING
STEAM ENGINES," upon the condition (amongst others) that I, the said Daniel
Rankin, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of
the said Letters Patent.
NOW KNOW YE, that I, the said Daniel Rankin, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following state-
ment in writing, reference being had to the accompanying Drawings, that is
to say:-
My said Invention has for its objects to simplify the construction and render
more efficient the working of oscillating steam engines, and consists in novel
combinations of various parts.
And in order that my said Invention, and the manner of performing the
same, may be properly understood, I have hereunto appended a Sheet of
explanatory Drawings to be herein-after referred to, and representing two modi-
fications of oscillating steam engines as constructed with my improvements.
Figure 1 is a plan, partly in horizontal section, of one modification, and
Figures 2 and 3 are corresponding vertical sections, taken as at right angles to
cach other. Only one cylinder 1 of the pair composing the engines is shown.
Each cylinder 1 is fitted with two piston rods 2, 3, which pass out through
stuffing boxes in the usual way, and which have their outer ends fixed to one
cross bead 4; this cross head 4 is jointed on the crank pin 5, being forged in
one piece, with a transverse opening for the crank pin to pass across, and to
receive the crank pin bearing brasses. These brasses are tightened up by
means of a screw 6 (or screws) tapped through the top of the cross head 4,
and bearing on the upper brass through the intervention of a cast-iron block.
The screw 6 is made tubular for the passage down it of lubricating matter

page_text: from a cup 7 formed or fitted on; or it might be connected to the upper end.
A simple cut-off valve 8 is applied outside of the steam trunnion 9, whilst
two slide valves 10, 11, are adapted to the cylinder 1 as close to the steam
trunnion 9 as possible, in order to reduce the passage between the cut-off
valve 8 and them, instead of such valves (10, 11,) being situated round at the
other side of the cylinder as ordinarily. The eccentrics 12 for working these
main slide valves 10, 11, are placed on the paddle or crank shaft 13 instead
of the intermediate shaft 14; they may however be placed on the latter, although
not so conveniently, as the bent levers for working the valves would have to
be of extra length.
A second modification is shown in Figures 4, 5, and 6, which are respectively
a horizontal section, a vertical section, and a side elevation. In this modifica-
tion a single main slide valve 15 is applied to the cylinder 1, just within the
steam trunnion 9, and is actuated directly from one or more eccentrics 12 by
means of a rod 16 jointed to the buckle or valve frame or fastening 17 in or
near the axis of oscillation of the cylinder, the oscillation being allowed for by
adapting to or forming in one piece with the buckle or frame 17, a trunk 18
working through a stuffing box 19 made of the same oblong form in cross
section as the trunk.
The arrangement of the main slide valve shown in Figures 4, 5, and 6,
and last herein-before described, may be used in combination with a cut-off
valve (8) applied just outside of the steam trunnion 9, or in combination with
the arrangement of piston rods (2, 3,) and cross head (4), or in combination
with both those arrangements herein-before described and shown in Figures 1, 2,
and 3.
By my improved arrangements thus described a comparatively long
stroke is more conveniently obtained than in ordinary oscillating engines,
whilst the valve gear is much simplified; and when cut-off valves are used
they are rendered more efficient in action in consequence of the space
between them and the main slide valve or valves being reduced to an
extent which has hitherto only been obtained or approached by adapting
complicated gear to work the cut-off valve on the cylinder instead of outside
of the trunnion.
Having thus particularly described my said Invention, and the manner in
which the same is to be performed, I have to state that I do not restrict
myself to the precise details herein described or delineated, but that what
I believe to be novel and original, and claim as the Invention secured to me
by the herein-before in part recited Letters Patent is, the arranging or com-

page_text: bining together of the parts of oscillating steam engines, substantially in the
improved modes herein-before described.
In witness whereof, I, the said Daniel Rankin, bave hereunto set my
hand and seal, this Eleventh day of October, in the year of our Lord
One thousand eight hundred and sixty-seven.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
DANIEL RANKIN. (L.S.)