Improvements in Governors for Marine Engines.
Year: 1895

page_text: Date of Application, 2nd Nov., 1895
Complete Specification Left, 19th Mar., 1896-Accepted, 30th May, 1896
Improvements in Governors for Marine Engines.
HERBERT JOHN MARSHALL, late Lieutenant R.N. and CHARLES CUTHBERT
MARSHALL, Mining Engineer both of Gayton Hall Ross Herefordshire, do hereby
declare the nature of this invention to be as follows:-
:-
By means of a pendulum hung to swing fore & aft for screw engines, or athwart
ships for paddle engines, to prevent the engines racing by cutting off steam,
partially or entirely, before the screw or paddle is lifted out of the water, the
amount of the cut off to be under the control of the engineer and easy of alteration
as circumstances require. For this purpose a length of the steam pipe (a) is fitted
with a balanced disc valve (b) connected by an arm (b) with the cross head
(running in guides (k)) of a small engine (c), the slide valve of which is actuated
by the lever (d) attached to the pendulum (e), arranged in the drawing to cause a
full stroke of the valve on the passage of the ship through one degree of inclination,
but variable at pleasure. The small engine (c), along with the air compressor (f),
is carried on suitable brackets cast on, or attached to, the length of steam pipe (a),
either at right angles to the pipe, or alongside as required by the position occupied
by the length of steam pipe.
The stroke of the engine (c) is controlled by the opening or closing of the three
air cocks in the compressor, so that for a certain degree of pitch the engineer can
arrange a certain amount of cut off of steam from the engines; and to provide
for an extreme pitch beyond this point a similar pendulum and segment are
attached to the leading air cock, which can be arranged to open the same and let
the engine (c) complete its stroke and close the valve (6) should the ship exceed
the pitch expected & provided for.
The pendulum (e) should be hung on pivots (9) where space permits, to prevent
its resting on either guide when the ship rolls (in the case of screw engines) or has
a list. The compressor is of sufficient diameter to ensure the air pressure being
sufficient to balance the steam pressure in use plus the condenser vacuum, and is
provided with an inlet valve at each end.
The steam cylinder is steam-jacketed.
The pendulum is set by means of set screws on the graduated arc to cut off or
throttle at any angle of inclination or pitch found necessary.
Dated this 31st day of October 1895.
H. J. MARSHALL.
CHARLES C. A
MADOTT ATT
COMPLETE SPECIFICATION.
Improvements in Governors for Marine Engines.
We, HERBERT JOHN MARSHALL late Lieutenant R.N. and CHARLES
CUTHBERT MARSHALL, Mining Engineer, both of Gayton Hall, Ross, Hereford-
shire do bereby 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 :-
According to this invention a throttle valve in the main steam pipe of the engine
We, HERBERT JOHN MARSHALL late Lieutenant R.N. and CHARLES
CUTHBERT MARSHALL, Mining Engineer, both of Gayton Hall, Ross, Hereford-
shire do bereby 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 :-
According to this invention a throttle valve in the main steam pipe of the engine

page_text: is opened and closed by the piston rod of a small steam cylinder controlled by an
air buffer cylinder, the slide valve of the steam cylinder being operated by a
pendulum.
Figure 1 is a side elevation showing a governor constructed according to this
invention.
Figure 2.is a transverse section on the line 2-2 Figure 1 (the steam and air
cylinders being omitted) and
Figure 3 is a transverse section on the line 3-3 Figure 1.
a is the main steam pipe and 6 is a throttle valve in it mounted on a spindle 61
passing out through a stuffing box and having a slotted arm & fixed at its outer
end. c is a small steam jacketed steam cylinder (the valve and valve box cover
heing removed to show the ports) and c is its piston rod which also forms the
piston rod of the air cylinder d. Steam is preferably supplied to the cylinder c
from the steam pipe a and the exhaust is preferably led to the main condensers so
as to prevent the escape of steam into the engine room. ddd are regulating
cocks in the air cylinder. The piston rod c¹ carries a block sliding between
guides and having fixed to it a pin working in a slot in the arm . eis the
valve rod of the steam cylinder. f is a triangular frame supported on hollow
trunnions f1f1 fixed to it which work in bearings a carried by the steam pipe a
9 is a pendulum pivotted at g' to the frame f. f is a slide on the segment forming
the base of the frame f and secured to it in any position by set screws f³. hh
are levers pivotted at to the slide and slotted to receive pins g³ and e³ fixed
respectively to the pendulum 9 and a sleeve el free to turn but not to move
longitudinally on the valve rod e. j is a frame supported on trunnions j¹¹ working
in bearings a carried by the steam pipe a. One of the trunnions is hollow to
receive the end of the valve rode which also passes through the hollow
trunnions f¹.
The frame carries a weight j' by which it is kept vertical. k is an ordinary
ball governor mounted on a vertical spindle k¹ working in bearings in the frame i
and carrying a pulley k driven by a band from a pulley on the top of a vertical
shaft l. is a bell-crank lever pivotted at k to the frame j. One end of the
lever ³ engages with a grooved pulley which is caused to rise and fall on the
spindle by the governor balls and its other end is slotted to receive a pin e*
on the valve rod e. The shaft works in fixed bearings and has fixed to its
lower end. a bevel wheel gearing with a bevel wheel m¹ on a shaft m.
shaft m has at its other end a friction wheel m' and works in bearings n' n¹ in a
frame n. pivotted at n². o is a set screw working in a fixed nut and having its end
bearing against the frame n. By turning the screw o the frame n is turned about
its pivot and the friction wheel m³ is pressed into contact with the screw shaft
of the engine.
The
P
The action of the apparatus is as follows:--If the stern of the vessel (which is
to the right of the drawing) rises and so brings the screw out of water the slide f
moves to the right relatively to the pendulum g and causes the levers / to pull
the valve rode to the left admitting steam to the right hand end of the cylinder c
moving the piston rod c¹ to the left and closing the valve b. The stroke of the
cylinder c is controlled by opening or closing the valves d' d' d' which can be so
set that a certain angle of pitch produces a certain degree of cut off of steam to
the engines. For an extreme pitch beyond this point a similar pendulum and
segment may be provided to open the air cock d' allowing the cylinder c to take a
full stroke and completely close the valve b immediately a certain angle of pitch
is exceeded. This may also be done by a slide valve. The angle of pitch at
which the apparatus begins to work is determined by the position in which the
slide is set on the segment. Free admission of air to the buffer cylinder is
provided by a valve opening inwards at each end of the same.
In some cases, especially with long ships, the screw may race when there is no
pitching, when this takes place the accelerated speed of the screw shaft causes the
balls of the governor k to diverge thus pulling the. valve.rod.e to the left and
.

page_text: closing the valve 6 as above described and this also takes place in case of the
fracture of the screw shaft; or the boss of the propeller.
It will be understood that the apparatus is applicable to paddle as well as to
screw engines being set in this case transversely instead of longitudinally to the
ship.
Having now particularly described and ascertained the nature of our said inven
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. The combination of a buffer cylinder with a cylinder whose valve is governed
by a pendulum and which opens and closes a throttle valve.
2. The combination with apparatus such as is referred to in Claim 1 of regulating
cocks on the buffer cylinder.
3. Operating the cocks of the buffer cylinder by means of a second pendulum.
4. The combination with pendulum governors of levers h substantially as
described.
5. Governors for marine engines substantially as described and shown in the
drawings.
Dated this Eleventh day of March 1896.
H. J. MARSHALL,
Carpmael & Co.,
Agents.