An Improved Method of and Means for Governing or Controlling the Speed of Marine Engines.
Year: 1894

page_text: Date of Application, 27th Nov., 1894
Complete Specification Left, 11th July, 1895-Accepted, 12th Oct., 1895
PROVISIONAL SPECIFICATION.
An Improved Method of and Means for Governing or Controlling
the Speed of Marine Engines.
I, GEORGE LEONARD ADDENBROOKE, of the Camera Club, Charing Cross
Road, in the County of London, Electrical Engineer, do hereby declare the nature
of this invention, as communicated to me by R. Macdonald, Dental Surgeon, of
Brisbane, Queensland, Australia, to be as follows
-
This invention relates to an improved method of and means for governing or
controlling the speed of the main engines used in propelling a vessel at sea, whereby
the so-called "racing" of the propeller (when the resistance due to its immersion is
reduced) is prevented or lessened.
In order to render the governing or controlling action more rapid and reliable
than other marine engine governors now in use, I employ the action of gravity,
electric and electro-magnetic energy, and mechanical means for the object in view,
aranged and operating in the following manner.
A bath of mercury is arranged in a tubular vessel placed longitudinally with the
ship and approximately horizontal or parallel with its water line. A cup or
enlarged part is added to each end of the tube, so that the pitching of the vessel
causes the mercury to flow to and fro in the tube, and to rise in one cup while it
falls in the other. Each cup is closed with a tight lid through which passes au
adjustable contact pin, insulated from the vessel, and forming part of an electric
circuit adapted to act upon and energize (through a relay) two powerful electro
magnets, respectively mounted on the steam and exhaust boxes of an auxiliary
steam engine cylinder. The electric circuit operates through the mercury in the
tube connecting the cups, and when the said cups are level (or parallel to the
required line of immersion) the mercury is tree of the contact pins, and the circuit
is broken. In this normal position of gravity, therefore, no electrical action
takes place; and no control is exercised upon the speed of the main engines,
which may also be considered as normal; but if pitching of the vessel occurs so as
to raise the propeller wholly or partially out of the sea, "racing" takes place,
contact occurs between the mercury and the corresponding contact pin, the electric
circuit is established, and the speed of the engine is controlled by means described
hereinafter. The contact pin of each mercury cup is preferably a screw spindle
passing through a nut in the lid of the cup, with an actuating hand wheel for
adjustinent.
When the electric circuit is completed, current flows round the cores of an
electro magnet and attracts an armature against the action of a spring, bringing
the relay into action which causes the main current to circulate through the
The
windings of the magnets mounted on the steam and exhaust boxes aforesaid."
poles of these magnets pass through brass covers to attract an iron piston in each
box, which piston is thus adapted to act as an armature to the poles of each magnet,
and also as a dash-pot. The attraction of each piston armature raises a spindle.
(against the action of a spring) and with the spindle an upper and a lower double
seated pot lid valve, thus arranged and operating to open the top and close the
lower valve in each box. The steam on the supply box enters between the valves,
and passing the upper valve enters the top of the cylinder through the upper
port, acting upon the piston to drive it down, which-in doing so-partially

page_text: closes the main engine throttle valve through the intervention of a connecting
rod and lever operating the throttle valve spindle; thus checking the speed of the
main engines. When the ship returns to its normal position of gravity and the
electrical circuit is broken the piston armature drops slowly (owing to its dash-pot
character) but assisted by the action of the valve spindle spring to overcome friction,
and the top valve closes, thus shutting off steam from the top of the cylinder
but admitting it at the bottom of the cylinder, to drive the piston upward and open
the throttle valve on the main steam pipe.
But
The valves in the exhaust box act in a similar manner, and by means of crossed
exhaust passages, the valves properly control the exit of the exhaust steam.
the exhaust ports are placed at some distance from the ends of the cylinder so that
the piston covers them in its travel, in order to promote cushioning, and to prevent
jer from the sudden action.
It will be seen that the pot lid valves require but a short stroke to give a
large opening to the steam, and therefore are well adapted for use with the
small range of action of the magnets; and by putting the poles of the latter
through the brass covers, outside stuffing boxes and their attendant friction are
avoided..
"
It has been found desirable, in some cases,, to slightly anticipate the "racing"
period, in order to check the speed of the engines when the vessel is rising
at the stern, and to do so a "guard" point is fixed by trial at which the contact pin
is so adjusted ae to make electrical contact in the manner already described.
But when the stern is falling, is found that the "racing "period' is prolonged
to a point slightly lower than the "up" "guard" point; and to meet these
conditions a valve is placed in the mercury tube, so arranged and adapted that
it allows the mercury to flow freely in the proper direction when the stern of the
ship is rising to the "guard" point, but retards the flow of the mercury when the
stern is falling, by which means the steam is shut off until the desired point
is reached, when the steam is freely admitted to produce the normal speed of
the engines.
Dated this 26th day of November 1894,
FAIRFAX & WETTER,
433 Strand, London, Agents for the Applicant.
An Improved Method of and Means for Governing or Controlling
the Speed of Marine Engines.
1, GEORGE LEONARD ADDENBROOKE, of the Camera Club, Charing Cross
Road, in the County of London, Electrical Engineer, do hereby 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 :-
This invention, as communicated to me by R. Macdonald, Dental Surgeon, of
Brisbane, Queensland, Australia, relates to an improved method of and means for
governing and controlling the speed of the main engines used in propelling a vessel
at sea, whereby the so-called "racing "of the propeller (when the resistance due
to its immersion is reduced) is prevented or lessened.
In order to render the governing or controlling action more rapid and reliable
than other marine engine governors now in use, employ the action of gravity,
electric and electro-magnetic energy, and mechanical means for the object in view.
These elements are arranged in the manner shown in the accompanying drawings,
to which reference is made in the further description of the invention.
Fig. 1 is an elevation of a vessel containing mercury;

page_text: Fig. 2 is an clevation of an electrical relay apparatus ;
Fig. 3 is an elevation of an auxiliary steam engine, with the electrical circuit
connections between these elements shown in dotted lines.
Fig. 4 is an enlarged view of the auxiliary engine, shown principally in section.
A bath of mercury is arranged in a tubular vessel a, of suitable length, placed
longitudinally with the ship and approximately horizontal or parallel with its water
line. A cup or enlarged part a' is added to each end of the tube, so that the
pitching of the vessel causes the mercury to flow to and fro in the tube, and to rise
in one cup while it falls in the other." Each cup a is closed with a tight lid,
through which passes an adjustable contact pin a', (or it may be through one of
the lids only, as shown), insulated from the mercury vessel, and forming part of an
electric circuit b, which embraces a source of electricity 6', and a relay device c.
The electric circuit is not completed when the vessel is upon an even keel, or in its
normal position, as the mercury is then free of the contact pin or pins, and no
control is exercised upon the speed of the main engines which is also considered as
normal; but if pitching of the vessel occurs so as to raise the propeller wholly or
partially out of the sea beyond' a certain degree then "racing" takes place, contact
occurs between the mercury in the cup a¹ and the contact pin a² the circuit bis
made, and the relay coils c, c are energized to form an electro magnet in a manner
well known.
When the relay coils become energized they attract an armature d secured upon
a flat spring carrying at its extremity a carbon holder e, and by means of a similar
carbon holder et mounted above e, and two carbon electrodes e³, e, the main electric
circuit, having therein a powerful source of electricity fl is completed, and the
current flows round the cores of the electro magnet y placed on the cover h of the
valve box of an'auxiliary steam engine), as shown in Figs. 3 and 4.
The electro magnet g has its iron cores screwed through the gun metal cover h,
of the steam valve box as shown in the section Fig. 4; and when it becomes a
magnet it attracts an iron armature g', formed as a piston, which is adapted to work
vertically within the cylindrical cover h, and to act as a dash-pot.
The armature
piston g is secured to a valve rod which passes through an intermediate cover i
and on which are also secured an upper and lower double beat valve, 22 and 23
respectively. As shown in the section Fig. 4, steam is admitted between the
upper and lower valves, and as the electric circuit f is not completed, the lower
valve is opened and steam is admitted to the bottom of the piston which is shown
at half stroke in the cylinder j, and this denotes normal speed of the main
propelling engines. In the elevation Fig. 3 the piston rod j¹ of the cylinder ; is
shown as attached to a fork ended connecting rod, whose upper end works on
the pin of a crank arm secured to the spindle of a throttle valve (indicated by
dotted lines) in the main steam pipe k; the upper part of the piston rod j¹ sliding
in a guide, as indicated; but I do not confine myself to this arrangement or
mode of applying the power of the engine.
The steam is admitted by the valve to the bottom of the piston in the
cylinder j, as aforesaid, and flows therefrom to the upper part of the exhaust valve
box through the passage as indicated. The exhaust valve box is also provided
with double beat valres, electro magnet 9. iron armature piston within a gun
metal cover h, acting as a dash-pot; exactly as described for the steam valve
box . Consequently, when the pitching of the vessel raises the vessel out of the
sea to a pre-determined degree, the electrical circuits and fare completed as
aforesaid, and the electro magnets g, g, on the steam and exhaust boxes i and /
are energized and attract their corresponding iron armature pistons gl, thus opening
the upper and closing the lower double beat valves, and . The steam then
flows into the upper part of the cylinder j and drives the piston down, and through
the intervention of the piston rod j¹ connecting rod and crank arm
throttle valve is closed sufficiently to reduce the speed of the main engines.
the
When the ship returns to its normal position of gravity the electrical circuit is
broken by the mercury leaving the contact pin a³, whereby the relay circuit b and

page_text: coils c become inert, and cease to attract the spring armature b; thus breaking off
the main electric circuit by the parting of the carbon electrodes ², ². The arc
caused by breaking the circuit affects only the carbons which are renewable.
Consequently, the electro magnets g, g, cease to attract the iron armature piston g¹
within the covers h, of the steam and exhaust boxes i and respectively, and the
said armature pistons drop slowly within the covers howing to their dash pot
character, but assisted by a spring m around each valve spindle, to overcome
friction. The upper valves are thus closed (as shown in the section of the steam
box i, Fig. 4), and the lower valve opened, to reverse or balance the main piston
in the cylinder j, and permitting the escape of exhaust steam therefrom on the
exbaust side 1; while the throttle valve in the main steam pipe k has been
opened.
The "pot lid or double beat valves and require but a short stroke to give
an opening of large area, and are therefore well adapted for operation with the
necessary short range action of the magnets; while by putting their poles through
the brass covers, outside stuffing boxes, with their attendant friction, are avoided.
It has further to be noticed that while the steam passages lead to the extreine ends
of the cylinder, the exhaust passages are placed at some distance from the ends,
so that the piston covers them in its travel in order to produce cushioning and
prevent jar from too sudden action.
It is desirable in some cases-to slightly anticipate the racing period, in order
to check the speed of the engines when the vessel is rising at the stern. To do
this, a "guard" point is fixed by trial and adjustment of the contact pin a², so as
to make electrical connection in the manner already described. But when the
stern is falling, the "racing" period is prolonged to a point slightly lower than
the " up "guard" point; and to meet these conditions, a valve is sometimes
placed in the mercury tube a and adapted to let the mercury flow freely in the
proper direction when the stern of the ship is rising to the "guard" point but
retards the flow of mercury slightly when the stern is falling; by which means the
steam is shut off until the desired point is reached, when the steam is freely
admitted to produce the normal speed of the engines. No particular form of valve
is shown for thus retarding the flow of mercury in one direction, but many ways
will occur to engineers to meet the condition pointed out.
It is to be understood that I do not limit myself to the particular form of
auxiliary engine or valves shown, nor to the special application of the engine to
the throttle valve in the main steam pipe as shown, as the steam may be shut off in
the passages between the cylinders of compound or triple expansion engines; or
I may apply the power of the engine to work the link motion or other form of
reversing gear.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is ;-
1. The herein described improved method of governing or controlling the speed
of marine engines, consisting of the employment of the action of gravity in making
and breaking electrical circuits, electro magnets arranged and adapted to act upon
the valves of an auxiliary steam engine, and suitable connections between the
piston rod of the said engine and the throttle valve or other suitable part of
the main propelling engines of a vessel, substantially as aud for the purpose
described.
2. The herein described improved means for controlling the speed of marine
engines, consisting of a longitudinally arranged mercury vessel having one or more
contact pins, a relay device, and source of electricity combined in an electrical
circuit; and a main electrical circuit having therein a powerful source of
electricity, electro magnets, and contact device operated to make or break the
circuit by the said relay device; an auxiliary steam engine with connections to
operate the main throttle valve or other suitable part of the main engines, and

page_text: having its steam and exhaust valves operated in one direction by the said electro
magnets, substantially as and for the purpose specified.
3. The combination of a steam or exhaust box having a cover of non-magnetic
metal with an electro magnet mounted thereon and with its core protruding through
to the inside of the said cover and an iron armature piston connected to the steam
or exhaust valves, substantially as and for the purpose herein described.
4. The combination of two electric circuits with the mechanical parts arranged
substantially in the manner shown in the accompanying drawings Figs. 1 to 4 and
adapted to operate substantially as and for the purpose herein described.
Deted thie 10th day of July 1895
FAIRFAX & WETTER,
433 Strand, London, Agents for the Applicant.
FAIRFAX & WETTER,
433 Strand, London, Agents for the Applicant.