IMPROVEMENTS IN GOVERNORS FOR MARINE ENGINES
Year: 1872

page_text: LETTERS PATENT to William Bruce Thompson, of Dundee, in the
County of Forfar, North Britain, for the Invention of “IMPROVEMENTS
IN GOVERNORS FOR MARINE ENGINES."
Sealed the 16th May 1878, and dated the 21st November 1872.
PROVISIONAL SPECIFICATION left by the said William Bruce Thompson
at the Office of the Commissioners of Patents, with his Petition,
on the 21st November 1872.
I, WILLIAM BRUCE THOMPSON, of Dundee, in the County of Forfar,
North Britain, do hereby declare the nature of the said Invention of
"IMPROVEMENTS IN GOVERNORS FOR MARINE ENGINES," to be as follows, that
is to say :-
This Invention relates to an arrangement of mechanism to be em-
ployed in lieu of or in conjunction with the ordinary governors of marine
engines, whereby the "racing" of the engines is more effectually
prevented.
The mechanism constituting the Invention consists of a shaft sup-
ported in brackets or in a framing, and on one extremity of which a
pulley is situate, the opposite extremity of the shaft being connected to

page_text: a rod which communicates with the spindle of the throttle valve or with
the engine governor. A fly wheel is also placed on the shaft, the boss
of which is at one side extended outwards, and formed with a bore wide
enough to receive a collar fixed on the shaft. Spiral or helical grooves
are formed at each side of the collar, into which pins fixed in the boss of
the fly wheel enter. Communication is effected between the apparatus
herein-before set forth and the main shaft of the engine by means of a
rope or band passed round a pulley on the said shaft, and also round the
pulley herein-before referred to.
66
"
Whilst an engine to which the apparatus constituting this Invention
is applied continues to work regularly a similar motion is communicated
by the rope or band to the apparatus, but when the engine begins to
race the acceleration of speed of the driving shaft due thereto is
communicated by the rope or band to the shaft of the apparatus herein-
before described, whereby the shaft is caused to revolve faster than the
fly wheel situate thereon. This has the effect of causing the pins in the
boss of the fly wheel to act in the spiral or helical grooves in the collar
on the shaft in such a manner as to effect a horizontal motion of the
shaft, which being communicated to the rod in connection with the
throttle valve or with the governor causes the said rod by means of a
bell crank or its equivalent to partially close the throttle valve, and
thereby diminish the supply of steam to the engine. When the engine
again becomes loaded, the momentum of the fly wheel of the apparatus
being at that instant greater than that of the shaft, the pins in the boss
of the said fly wheel acting in the spiral or helical grooves in the collar
on the shaft cause a horizontal motion of the shaft the reverse of that
herein-before set forth, whereby the rod is made to open the throttle
valve to an extent sufficient to supply the requisite amount of steam to
perform the work of the engine.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of November, in the
year of our Lord One thousand eight hundred and seventy-two, in the
36th year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said William Bruce Thompson, Her special
license that I, the said William Bruce Thompson, my executors, adminis-
trators, and assigns, or such others as I, the said William Bruce
Thompson, my executors, administrators, or assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN GOVERNORS FOR MARINE ENGINES," upon the condition
(amongst others) that I, the said William Bruce Thompson, my
executors or adminstrators, by an instrument in writing under my
hand and seal, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said William Bruce Thompson, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to
say:―
My said Invention relates to an arrangement of mechanism to be em-
ployed in lieu of or in conjunction with the ordinary governors of marine
engines whereby the "racing" of the engines is more effectually
prevented.
And in order that my said Invention may be properly understood I
now proceed more particularly to set forth the system, mode, or manner
in or under which the same is or may be used or practically carried into
effect, that is to say :-
On the Sheet of Drawings hereunto appended Figure 1 is a vertical
section of my improved governor for marine engines, and Figure 2 is a
plan of a detached portion of the same, as shewn by these Figures.

page_text: "
The governor consists of a shaft A supported in bearings a formed in a
bracket B. On one end of the shaft A a pulley C is situate, whilst a
portion of the shaft A at the opposite end is constructed hollow, and with
a slot D therethrough. Within the hollow end of the shaft A is a second
shaft E, one extremity of which is attached to a loose collar F placed on
the shaft A. The extremity of the shaft E is attached to the collar F by
means of a key G which passes through the shaft E and slot D into the
collar F. The other extremity of the shaft E is connected by means of
a swivel joint H to one end of a rod I, which is attached at the other
end to the spindle of the throttle valve of the engine. A fly wheel J is
placed loose on the shaft A, and is kept in position thereon by means of
collars b, one of which is formed on the shaft A, whilst the other is
attached thereto, as shewn. The boss K of the fly wheel J is at one side
extended outwards, and formed with a bore wide enough to receive the
collar F. The collar F is provided at each side with a spiral or helical
groove L, each of the grooves L traversing in contrary directions halfway
or thereabouts round the circumference of the collar F, as shewn more
particularly at Figure 2, which is a plan of the collar F, the groove L
situated at the under part thereof being shewn in dotted lines. At the
outward part of the boss K. two pins or studs M are situated, the pins or
studs M projecting at the inside of the boss K far enough to enter into
the spiral or helical grooves L. Communication is effected between the
governor and the main shaft of the engine by means of a rope or band
passed round a pulley on the said shaft, and also round the pulley C
situated at the end of the shaft A.
Whilst the engine to which the governor constituting this Invention
is applied continues to work regularly, an uniform motion is com-
municated by the rope or band to the governor; but when the engine
begins to "race" the accelerated speed of the driving shaft is thereby
communicated by the rope or band to the shaft A of the governor,
whereby the shaft A is caused to revolve faster than the fly wheel J
situate thereon. This has the effect of causing the pins or studs M in
the boss K of the fly wheel J to act on the spiral or helical grooves L in
the collar F on the shaft A in such a manner as to cause the collar F to
slide along the shaft A, thereby moving the shaft E longitudinally, and
the shaft E being coupled to the rod I in connection with the spindle of
the throttle valve causes the rod I, by means of a bell crank or its
equivalent to partially close the throttle valve, and thereby diminish the

page_text: supply of steam to the engine. When the engine again becomes loaded
the momentum of the fly wheel J of the governor being at that instant
greater than that of the shaft A, the pins or studs M in the boss K
acting in the spiral or helical grooves L in the collar F cause it to slide
on the shaft A in a reverse direction to that herein-before set forth, when
the rod I is caused to open the throttle valve to an extent sufficient to
supply the requisite amount of steam to the engine.
Having now described and particularly ascertained the nature of my
said Invention, and the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, I would observe
in conclusion that what I consider novel and original, and therefore claim
as the Invention secured to me by the herein-before in part recited
Letters Patent is, the arrangement and construction of steam engine
governor herein-before described and shewn on the accompanying Sheet
of Drawings, or any mere modification thereof.
In witness whereof, I, the said William Bruce Thompson, have
hereunto set my hand and seal, this Sixteenth day of May, One
thousand eight hundred and seventy-three.