IMPROVED MEANS OF WORKING THE WASTE COCKS OF ENGINE CYLINDERS
Year: 1871

page_text: PROVISIONAL SPECIFICATION left by Robert Francis Fairlie at the
Office of the Commissioners of Patents, with his Petition, on the
14th October 1871.
I, ROBERT FRANCIS FAIRLIE, of 9, Victoria Ohambers, in the City
of Westminster, Engineer, do hereby declare the nature of the said
Invention for "IMPROVED MEANS OF WORKING THE WASTE COCKS OF ENGINE
CYLINDERS," to be as follows:-—
My Invention consists of improved means of working the waste cocks
of engine cylinders, and is as follows :—
Adjoining the engine cylinder is a small cylinder, the piston rod of
which carries two valves one at each end of the engine cylinder. The
small cylinder is in communication with the boiler, so that as long as
the
the pressure of steam or water is maintained in the small cylinder,
said valves are kept in such a position as to close the outlets formed for
waste water at each end of the engine cylinder. But when the pressure
of steam or water in the small cylinder is removed by the communication
with the boiler being cut off in any suitable manner, a spring the force

page_text: of which has previously been overcome by the steam or water pressure,
acts upon the piston rod so as to force back the valves. The waste
water outlet at each end of the engine cylinder is thus opened, allowing of
the escape of the wasto water or steam. To compensate for the expansion
of the piston rod due to the heat of the engine cylinder, the length of
the rod may be made adjustable by means of a screw. If thought
desirable two small cylinders may be employed, one for each end of the
engine cylinder, and both being in communication with the boiler they
may have distinct or separate piston rods, cach rod being provided with
a spring.
According to another arrangement by which the waste cocks of two
engine cylinders may be worked by one small cylinder, I connect waste
water outlets at each end of cach engine cylinder with distinct outlet
orifices in the small cylinder, and I employ a chambered piston in the
small cylinder, there being one chamber opposite the small pipe leading 1
to each end of each cylinder, and opposite the outlet or exhaust orifice
in the small cylinder, so that when the pressure from the boiler is kept
up in the small cylinder, the communications otherwise open through
the orifices in the small cylinder, and passing through the chambered
piston and small connecting pipes to each end of cach engine cylinder 2
are closed; but when the said pressure is removed the piston is forced
back by a spring, bringing the chambers or recesses in the piston again
opposite the small pipes communicating with each end of each engine
cylinder, consequently the communications are opened from each end of
each engine cylinder to exhaust the waste water in the cylinders, and i
let it drain away.
The cock which shuts off the pressure from the boiler to the small
cylinder opens an outlet orifice, so that not only the pressure may be
removed from the piston in the small cylinder but any condensed water
will also drain away, therefore the cocks communicating with the boiler a
and small cylinder should be placed low enough to prevent any con-
densed water remaining in the pipes, that all shall drain away.