ELECTRO-MAGNETIC MARINE GOVERNOR
Year: 1886

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I, GEORGE ALEXANDER SMITH, of 64 Alexander Street, Goole, Yorkshire, Officer
in Her Majesty's Customs do hereby declare the nature of my invention for
"ELECTRO-MAGNETIC MARINE GOVERNOR " and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
My Invention relates to a novel method of automatically controlling the speed
of marine engines by the agency of an electric current, such control always being
relative and corresponding to a certain degree of immersion of the screw propeller
or other device employed for the propulsion of vessels.
The principle upon which an efficient, reliable, marine governor ought to be
chosen, should be that which is based upon the direct motion of the wave-line of
the vessel and not upon any application of centrifugal and centripetal force set up
by the motion of the engines as in the ordinary governors used for regulating the
speed of stationary engines on land. In a marine governor, the varying depth of
the water line at the stern of the vessel must be instantly transmitted as motion
to open or close valves which shall regulate the admission of steam into the
cylinders of the engine or vary the area of emission of steam into the condensers
by throttling the eduction. Now in carrying out the regulating action above
mentioned, I employ in accordance with my Invention, a current of electricity as
the actuating agent, inasmuch as its conversion into magnetic. force and motion is
practically instantaneous, and irrespective of the distance between the varying
water line and the point of application of the governor in the engine room of the
vessel. For the generation of said electrical current I prefer to employ a dynamo-
electric generator of suitable construction and of a calibre proportionate to the
work required to be done. It is necessary, in order to ensure the proper working
of the apparatus in accordance with my Invention that the polarity of the field
magnet of the aforesaid dynamo electric generator shall be constant, and therefore
in order to attain this result, I employ the method of winding the exciting coils of
said field magnets ordinarily known as "Shunt winding" or I may use a compound
of "shunt" and "series" or a "separately excited" field, or again I may use a
permanent magnet to form a magnetic field of unchangeable polarity, or a com-
bination of any of the aforesaid methods of winding the exciting coils I arrange
the dynamo-electric generator aforesaid in such a manner that motion is imparted

page_text: to it from the engines by means of belts, friction gear, ordinary toothed gearing, or
by the intervention of any other means which shall ensure a proper rate of speed
being attained.
In order that the contrivance according to my Invention may be the more
readily understood, and to illustrate the application of same, I have appended the
accompanying sheet of drawings. Figure 1 represents a side elevational view of
the dynamo-electric generator, and its electrical connection with the propelling
apparatus at the stern of the vessel, and Figure 2 represents a plan view of the
same.
The same letters of reference are employed to denote like or corresponding parts
in each of the views.
The vertical framing a a which supports the bearings of the armature spindle b
of the generator is so constructed as to extend beyond the flat polar surface c. c. of
the field magnet; and, attached to it and extending across the polar surface afore-
said is a plate d of brass or other non-magnetic material. To said plate d two
electro-magnets e et are suspended. These latter are of special form and are so
arranged as to be free to turn over the face of the polar surface c. c aforesaid.
The points of free suspension of the electro-magnets e e¹ consist of suitable metal
spindles, which passing through the plate d, have attached thereto-by keys or
other suitable method for ensuring rigidity-two pinions f, f¹, of equal diameter
and pitch.
Placed centrally between said pinions f; f¹, on the upper side of the plate d, is
the axle of a corresponding toothed quadrant g. forming the segment (or segments)
of a circle the diameter of which bears a given ratio to the pinions. f, f¹ aforesaid.
Said toothed quadrant g carries a projecting slotted arm h which is connected by
suitable rods, or other mechanical appliances, direct to the valves in the steam and
eduction pipes. Or, in the case of large engines where the pressure upon such
valves is great, the slotted arm h above mentioned may be caused to operate the
slide valve of a small hydraulic or steam cylinder, the piston of which would in
such case be attached to the regulating valves, and by its motion control them.
On the under side of the plate & are fixed suitable blocks i of vulcanite or other
non-conducting material, to which are attached the brushes j, bearing upon the
commutators or collectors k and suitable connections placed thereon for passing a
current of electricity around the helices of the suspended electro-magnets e, e¹,
during half a revolution.
The above described apparatus may be placed in any convenient part of the
engine room to allow of the dynamo-electric generator being driven from the main
shaft of the engine, and where the requisite connections between the slotted arm h
and the valves aforesaid can be conveniently arranged.
As near as can be arranged to the stern of the vessel, and on a plane co-incident
with that of the propeller shaft, I fix a metal cylinder l, of suitable dimensions, in
a vertical position, and in such a manner that its. lower end is open and in free
communication with the sea. Said cylinder contains within it a smaller oylinder
or float m (shewn in dotted lines in the drawings) filled with air and hermetically.
sealed.
The cylinder or float m is free to move up and down within the containing
cylinder, and may be furnished with suitable guides to keep it in a central
position without interfering with its freedom of motion in a vertical plane. The
cover of the cylinder is furnished with a stuffing box and gland n, through. which
passes a rod o which is attached to and moves with the float m, and is also
furnished with an adjustable metal arm p which is fixed at right angles to said
rod o.
Attached to the side of the cylinder but electrically insulated from it and from.
each other, are two metallic rods q and r, so arranged that the metal arm p afore-
said makes contact with one rod q in its upward movement, and with the other
rod r in the downward movement of said arm p. All points of contact are tipped
with platinum or other conducter of electricity not subject to oxidisation,.,and

page_text: terminal connecting screws, or binding posts, may be fitted to each of the insulated
metallic rods q and r aforesaid. The cylinder may be in electrical contact with
the metal forming the ship's side and is also furnished with an air pipe s leading
well above the normal water level.
"
The device or contrivance in accordance with the foregoing description is put
into automatic electric and mechanical action as follows:-The wire leading from
the positive brush of the generating armature is coupled by a branch wire with
one brush of each suspended electro-magnet e, e¹, above the polar surface c, c of the
field magnet. Two wires suitably insulated, lead, from each of opposite brushes of
the suspended electro-magnets e, e aforesaid, through the propeller shaft tunnel or
alley to each of. the insulated rods q and r. The wire leading from the negative
brush of the generating armature may be led to the nearest mass of metal which is
in electrical contact with the ship's side, or I may carry it direct to the cylinder
in the stern of the yessel; taking care to insulate said wire throughout its length.
The contacts q and r are so arranged that as the stern of the vessel is lifted by
the action of the waves to such an extent as to cause the engines to "; race the
float m falls within the cylinder to a degree proportionate to the diminishing
water level, until the arm p is brought into contact with the insulated rod r when
an electrical circuit is established through the system, whereby the cores of the
suspended electro-maguets e, e¹ are magnetised. These being so wound as to
present poles of similar sign to those of the polar surface of the field magnet
beneath it. This magnetic polarity produces motion, the electro-magnet e having
a tendency to get its polar extremities opposite to its normal position by reason of
the attraction of unlike poles and repulsion of like poles, thereby producing half
a revolution of the magnet e and consequently motion is imparted to the segmental
wheel through the pinion f. The commutator k upon the spindle of the sus-
pended electro-magnet e then changes the direction of the current through the
coil again, and rotatory motion is continued in the same direction while the
electric current is complete or until the segmental wheel g has moved through half
of its entire travel.
The regulating valves,-which are not shewn, but which may be balanced
valves of any suitable type-are closed by the action of the slotted lever or arm h,
either direct, or by the interposition of a hydraulic, or steam cylinder, as before
mentioned. The increased speed of the engines due to the decreased load, is thus
checked, until the stern of the vessel falls and the propeller is again immersed,
when the water rising in the cylinder lifts the float m until the arm or lever h is
in contact with the insulated rod 9 when the electrical circuit is established
through the other suspended electro-magnet e¹, the coils of which are so wound
and the brushes upon the commutator, adjusted with such "lead" as to cause
the direction of rotatory motion of said electro-magnet e¹, to be opposite to that of
the electro-magnet e first referred to.
Similarly this rotatory motion is transferred to the segmental wheel or quadrant g
and slotted lever or arm h which latter now moves in the opposite direction and
thereby opens the valves and again admits full steam to and from the cylinders of
the engines.
"
The electro-magnet e being electrically "cut out of circuit is non-magnetic,
save by induction from the constant polar surface, and being thus neutral, is easily
revolved by the other electro-magnet el which is in action through the toothed
gear aforesaid. The slot in the end of the arm or lever h allows of the degree of
opening or closing the valves to be regulated to any desired extent.
In cases where the dynamo-electric generator is used for electric lighting or
other purposes on board ship in addition to the automatic regulation of the speed,
and under circumstances which would render impracticable the use of the field
magnet of the generator as the polar surface before mentioned, I may use an
independent electro-magnet, the exciting coils of which may be placed in " multiple
arc" with the main circuit of such a dynamo-electric generator, in which case the
apparatus would be substantially the same in construction and in the method of

page_text: operating same, as in the case of the device in accordance with my Invention as
herein before described excepting only the revolving generating armature within
the field herein before referred to.-Also under other conditions, I may employ a
permanent magnet to maintain the constant polar surface before referred to; but,
in all cases, the suspended electro-magnets and the intermediate gearing connected
therewith, as also the cylinder and float hereinbefore referred to and described,
remain substantially as herein set forth.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is:-
First For controlling the speed of marine engines, the method adopted for
ensuring automatic electrical contact dependent upon the motion of the vessel,
substantially as herein described and shewn.
Secondly The application of intermittent magnetism for controlling the
opening and closing of valves and so regulating the rate of supply of steam to and
from the cylinders of marine engines, substantially as herein described and shewn.
Thirdly-In an electric system of automatic regulation of speed, the com-
bination of a movable and variable electro-magnet or electro-magnets, with a
stationary and constant magnet, and mechanical devices or contrivances for trans-
ferring the motion thereby obtained, to the valves of a marine engine, substantially
as herein described and shewn.
Fourthly The combination of a dynamo-electric generator and automatic
regulator substantially as herein described and shewn.
Dated this Third day of June 1886.
JAMES STEVENSON,
Agent for Applicant.