IMPROVED MEANS FOR PREVENTING THE RACING OF MARINE ENGINES
Year: 1877

page_text: LETTERS PATENT to William Alexander Brice, of 53, Chancery Lane, in the
County of Middlesex, for the Invention of "IMPROVED MEANS FOR PREVENTING
THE RACING OF MARINE ENGINES."
Sealed the 8th May 1877, and dated the 10th March 1877.
PROVISIONAL SPECIFICATION left by the said William Alexander Brice
at the Office of the Commissioners of Patents on the 10th March 1877.
WILLIAM ALEXANDER BRICE, of 53, Chancery Lane, in the County of Middlesex.
"IMPROVED MEANS FOR PREVENTING THE RACING OF MARINE ENGINES."
My Invention relates to improved means of govering the speed of marine
engines to prevent what is known as "racing" when the screw is momentarily
raised out of the water.
The Invention consists in a centrifugal governor of any suitable construction
driven by toothed gear direct from the screw shaft, and operating a throttle valve
of any kind in one of two steam pipes, by which for the purpose of my Invention
steam is supplied to the engines, that is to say, where one pipe has been used before
to convey steam from the boiler to the engines, I use two pipes, and in one of
them I apply a valve operated by the governor, as above described, so that imme-
diately the screw commences to turn at a higher speed the valve will be closed and
the steam cut off through that pipe.
If the sectional areas of the two pipes be equal half the steam supply is thus cut
off, the other half through the other pipe being intended to keep the engines in
motion at the same speed; but I do not limit myself to pipes of equal size, but use
pipes of such relative dimensions as may enable that object to be attained.

page_text: My Invention relates to improved means of governing the speed of marino
engines to prevent what is known as "racing" when the screw is momentarily
raised out of the water.
The Invention consists in a centrifugal governor of any suitable construction
driven by toothed gear direct from the screw shaft, and operating a throttle valve
of any kind in one of two steam pipes, by which for the purposes of my Invention
steam is supplied to the engines, that is to say, where one pipe has been used
before to convey steam from the boiler to the engines I use two pipes, and in one
of them I apply a valve operated by the governor, as above described, so that
immediately the screw commences to turn at a higher speed the valve will be closed
and the steam cut off through that pipe.
If the sectional areas of the two pipes be equal half the steam supply is thus cut
off, the other half through the other pipe being intended to keep the engines in
motion at the same speed; but I do not limit myself to pipes of equal size, but use
pipes of such relative dimensions as may enable that object to be attained. The
throttle valve may if desired be placed in the exhaust pipe with the same object.
The accompanying Drawing represents one arrangement of my Invention.
A is the screw and B the screw shaft; C is an ordinary ball or other kind of
governor driven at a considerably higher speed than that of the shaft B by a bevel
wheel D keyed on said shaft gearing with a bevil pinion E on the governor spindle or
by any other arrangement of gearing. The sliding collar of the governor which is acted
on by the balls in the usual way is connected through a series of levers and rods F, G,
or other connections with a lever H of a throttle or other valve in one, K, of the two
pipes which convey steam from the boiler to the engine. By this arrangement the
governor being driven direct by the screw shaft and at a much higher speed than the
shaft, when the screw commences to turn faster than its normal speed the speed of
the governor will be almost instantaneously increased and to a much greater extent;
thus the increase of speed of the screw shaft for even a fraction of a revolution is
sufficient to make the governor balls fly out, operate valve, and cut off the steam
through the pipe K, thereby limiting the supply to what is necessary to maintain
the engine at the normal speed until the screw again dips in the water, whereupon
the valve is again opened to adinit the full supply steam to the engine.
Instead of two steam pipes I may use a single steam pipe made two part by a
longitudinal division plate; it will then be observed that I furnish a certain constant
supply of steam that will always suffice to drive the machinery at a moderato speed,
while the governor only affects the speed above that by curtailing, or in the event
of the screw being thrown out of the water, cutting off entirely the steam passing
through the governor valve pipe.
Having described the nature of my said Invention, and the manner of performing
the same, I declare that what I claim as my Invention to be protected by the
herein-before in part recited Letters Patent is, in a marine engine, the combination
of a two part steam pipe or its equivalent with a steam valve, governor, and screw
shaft with intermediate connecting and driving mechanism, substantially as
described.
In witness whereof, I, the said William Alexander Brice, have hereunto set my
hand and seal, this Nineteenth day of July, in the year of our Lord One
thousand night lundred and seventy-seven
WILLIAM A. BRICE. (L.S.)