FIRSTLY, FOR CASTING STEAM CYLINDERS OF STEAM ENGINES IN THE FORM OF A SEGMENT OF A CYLINDRICAL RING OR CIRCLE; AND, SECONDLY, FOR THE MACHINE FOR BORING THEM TRULY CYLINDRICAL, AND RETAINING THE LINE OF THE BORE ON THE CURVE OF A TRUE CIRCLE
Year: 1863

page_text: LETTERS PATENT to William Henry Cole, of No. 52, Gracechurch Street,
in the City of London, Merchant, for the Invention of "FIRSTLY, FOR
CASTING STEAM CYLINDERS OF STEAM ENGINES IN THE FORM OF A SEGMENT OF
A CYLINDRICAL RING OR CIRCLE; AND, SECONDLY, FOR THE MACHINE FOR BORING
THEM TRULY CYLINDRICAL, AND RETAINING THE LINE OF THE BORE ON THE CURVE
OF A TRUE CIRCLE."-A communication from abroad by Samuel Woodruff
and Henry B. Beach, both of Hartford, in the County of Hartford and
State of Connecticut, in the United States of America.
Sealed the 26th January 1864, and dated the 9th December 1863.
COMPLETE SPECIFICATION filed by the said William Henry Cole at the
Office of the Commissioners of Patents, with his Petition and Decla-
ration, on the 9th December 1863, pursuant to the 9th Section of the
Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HENRY COLE, of No. 52, Gracechurch Street, in the City of London,
Merchant, send greeting.
WHEREAS I am in possession of an Invention, "FIRSTLY, FOR CASTING
STEAM CYLINDERS OF STEAM ENGINES IN THE FORM OF A SEGMENT OF A CYLINDRICAL
RING OR CIRCLE; AND, SECONDLY, FOR THE MACHINE FOR BORING THEM TRULY
CYLINDRICAL AND RETAINING THE LINE OF THE BORE ON THE CURVE OF A TRUE
CIRCLE," and have petitioned Her Majesty to grant unto me, my executors.
administrators, and assigns, Her Royal Letters Patent for the same, and
have made solemn declaration that the same has been communicated to me
from abroad by Samuel Woodruff and Henry B. Beach, both of Hartford,
in the County of Hartford and State of Connecticut, in the United States
America

page_text: NOW KNOW YE, that I, the said William Henry Cole, do hereby declare
that the following Complete Specification under my hand and seal fully
describes and ascertains the nature of the said Invention, and in what manner
the same is to be performed, in and by the following statement and accom-
panying Drawings, that is to say :-
1st, in casting steam cylinders of steam engines in the form of a segment
of a cylindrical ring or circle; and, 2nd,in the machine for boring them truly
cylindrical, and retaining the line of the bore on the curve of a true circle.
Figs. Nos. 1 and 2 on the Drawings annexed show a plan and side view
respectively of a steam engine with a segmental cylinder, of which the fol-
lowing is a description.
(A) is the steam cylinder fastened through flanges to the bed plate or frame
(B) on the casting; with the cylinder are cast two stands or bearings (C,C,) the
centres of which when bored coincides exactly with the radii point of the circle
which forms the centre line of the cylinder. The steam chest (D) is also a
part of the same casting as the cylinder. The steam piston is made in the
usual form with packing rings, springs, &c.; a piston rod (E) is attached to
each end of the piston head, and passes out through a stuffing box made in
each cylinder head (F, F',) and abut together at a point above in the piston
rod, arm, or carrier (G), to which it is securely fastened, and completes the
circle, of which the centre line of the bore of the cylinder forms a part. The
forked end of the connecting rod (H) is attached to pins in the carrier arm (G),
and the other or single end is connected to the crank pin of the crank (I) on
the crank shaft (K). The chord of the arc described by the connecting rod
pin in the carrier arm (G) is of course just equal to the diameter of the circle
described by the crank pin, and when the piston is at half stroke in the
cylinder the right line passing through the centres of the carrier arm (G)
and the connecting rod pin, and the line passing through the shaft and
crank pin are nearly parallel, and the ends of the connecting rod form almost
a right angle with each respectively. When the crank (I) is on the dead
centre (as it is called), or in the position shown by the dotted lines in red,
the connecting rod still makes an angle with the imaginary line passing
through the pin in the carrier arm and centres of its journals (C, C,) and as
the direction of the power is on the circumference of a circle passing through
this angle, or, in other words, as the power is applied at the extremity. of a
lever forming an angle with the end (L) of the connecting rod (H), and
having its fulcrum at (M), the crank is moved over the dead point as-smoothly
and with as much apparent ease as over any other point in the crank circle.
In ordinary engines, having their cylinders horizontal, when theerank is on the

page_text: dead centre, the direction of the power is in a horizontal line coincident with
the right line passing through the piston rod, connecting rod, and crank pin,a
condition that never can occur with the segmental cylinder engine. Again, as
the motion of the piston is on the circumference of a true circle, and sus-
pended and vibrating in bearings located at its centre, the cylinder is relieved
of the weight of the piston, and the wear is alike on all sides, whereas in large
horizontal straight cylinders the weight of the piston, which is considerable, is
received on the bottom part of the circumference, making the wear irregular
and involving the necessity of re-boring, or the substitution of a new cylinder
to keep it true with the other working parts. With a segmental engine, such
as above described, the crank shaft can be located at almost any point outside
of the cylinder, above or below, or at either end of it, without in any way
interfering with its efficiency, or destroying any of the advantages peculiar to
it, and thus making its adaptation to locality universal. It is peculiarly fitted
for marine vessels when the moving power is steam, but more particularly to
ships propelled by screws, as the entire machinery can be placed below the
water line, and for this class of vessels its utility can scarcely be overrated.
A pair of these engines can be placed side by side on the same side of keel,
and connected direct to cranks at right angles with each other on the shaft
without any guides, side rods, or cross heads, indispensable auxiliaries of the
usual form of marine screw engines; or a single segmental engine can be
placed on each side of keel and connected direct to the same crank pin,
producing the same combination attained in the prevailing class of ship
engines using double cranks, and neutralizing the dead point as effectually
as when two cranks are used, guides, side rods, and cross heads being dis-
pensed with as in the other case.
Boring machine.-The machine for boring the cylinder is represented in
plan and elevation, Figs. 3 & 4, and consists of the frame or table (F), and
the segmental arbor (a) that holds the cutting tool (k), and the device for
obtaining the circular and feed motion to the tool itself.
Description. The arbor (a) shown in section and operating on a cylinder
is made hollow, and is a segment of the same circle as that of the cylinder,
but its diameter is made smaller than the bore of the cylinder, so as to permit
the chips to fall down between its periphery and the edge of the cutting tool;
one end (b) is elongated and forms a solid bent arm, having a hub (c) on its
extreme end, which it is suspended in the bearings (C, C,) cast on the
cylinder. A forked arm (d, d,) is also cast on this end of the arbor. Near
the other extreme end of the arbor an opening (0) is left out to admit the
introduction of a pair of bevel wheels (e, e'.) The spindle (f) of one of these

page_text: wheels has its bearings (g, g',) cast on the arbor, the other wheel is keyed to
a spindle (h), the end (i) of which forms the tool post, into which the cutting
tool (k) is inserted and held in place by a set bolt (w). On the shaft (m),
upon which the arbor is hung,a spur wheel (') with a long hub revolves loose
on the shaft. On this hub is keyed two driving pulleys, the small one (p)
and the large one (p'). This spur geer (n') drives another (n) of the same
size on the countershaft (r), having its bearings fastened to the arbor; on this
countershaft is a bevel wheel (s), which drives another (s') on the end of the
spindle (f), which in turn gives the proper rotative motion to the cutting
tool (k) through the bevel wheels (e, e'.)
Feed motion. The small pulley (p) ou the shaft (m) drives the counter-
shaft (a) hung in bearing on the frame (F), and this in turn drives the
countershaft (t) by the pulleys (3, 1.) On the countershaft (t) is keyed a
bevel wheel (u), which drives another (u'), the spindle of which has its
bearing in the yoke (V). This spindle has a square-threaded screw cut on
it for nearly its whole length, and works into a nut (N) hung on journals in
the forked arm (d) on the end of the boring arbor, producing a slow longi-
tudinal movement to it around its centre (m), which is the requisite feed
motion in that direction.
Segments of cylindrical rings or steam cylinders of the form named herein
can also be bored perfect and true by reversing the operation as described in
the foregoing, that is, the arbor carrying the cutting tool can be moved
throughthe cylinder longitudinally, making a cut its wholelength, thendrawn
back to the place of starting and adjusted for the next cut, and so on, until
the boring is completed; this action, it will be seen, is identical with that of
an ordinary power planer, with this exception, that the tool cuts on a curved
instead of a horizontal plane, and is fed around on the periphery of the
cylinder under operation.
In witness whereof, I, the said William Henry Cole, have hereunto set
my hand and seal, this Ninth day of December, in the year of our
Lord One thousand eight hundred and sixty-three.
WILLM. H. COLE. (L.B.)