IMPROVEMENTS IN GOVERNORS APPLICABLE FOR GOVERNING: STEAM ENGINES A
Year: 1882

page_text: LETTERS PATENT to William Phillips Thompson, of the Agency for Foreign
Patent Solicitors, 6 Lord Street, Liverpool, in the County of Lancaster and
of 323 High Holborn, in the County of Middlesex Civil Engineer for an
Invention of "IMPROVEMENTS IN GOVERNORS APPLICABLE FOR GOVERNING:
STEAM ENGINES A communication to him from abroad by Franklin D.
Cumnver of Detroit in the County of Wayne and State of Michigan one of
the United States of America
"
COMPLETE SPECIFICATION filed by the said William Phillips Thompson
at the Office of the Commissioners of Patents on the 23rd October 1882.
WILLIAM PHILLIPS THOMPSON, of the Agency for Foreign Patent Solicitors,
6, Lord Street, Liverpool in the County of Lancaster, and of 323, High Holborn,
in the County of Middlesex, Civil Engineer, IMPROVEMENTS IN GOVERNORS
APPLICABLE FOR GOVERNING STEAM ENGINES Communicated to me from abroad:
by Franklin D. Cumnver of Detroit in the County of Wayne and State of
Michigan one of the United States of America.
This invention in a governor consists essentially in combining with flying
weights arranged to revolve in a vertical plane, a stationary weight, operating
to furnish a centripetal force, that may be easily adjusted to equal, or nearly
equal, as may be desired, the centrifugal force of the flying weights when
they are at their inner position and revolving at the desired speed: also in certain
other novel features of construction as will be hereinafter more particularly
pointed out and specified in the claims.
In the drawings:—
Fig. 1, presents a view in section and elevation of an engine governor embodying
the features of this invention.
Fig. 2, is a seperate view illustrating the arrangement of the flying weights.
It is well known that the office of a governor is not to hold the engine against
any variation in its speed; but is designed simply to restore the speed quickly and
as nearly as possible to its normal state when any variation has taken place.
ID 637

page_text: The difference between the normal or desired speed and that obtained or main-
tained by the governor and the time required by the governor to adjust itself to
the changes in speed chiefly occasioned by change of load or pressure, are the true
and best measures of the value that the governor may possess.
It is the object of this invention to produce a governor of that type wherein the
flying weights revolve in a vertical plane, which shall respond quickly to any
change of speed, in which the centripetal mechanism shall not itself revolve with
the flying weights and in which the increased or decreased centrifugal force of the
flying weights as their radial distances increase or decrease, is compensated so that
at all speeds the conditions in the governor shall be constant, or more fully that
under all conditions the centrifugal and centripetal forces shall increase or decrease
in the same ratio, or as nearly so, as may be desired.
To this end. A is a shaft, B is an eccentric which ordinarily moves the main
admission valve C is a concentric shaft sleeved upon the shaft B: D is an annular
case which contains the Bying weights: it is permanently attached to the shaft B,
to which is also attached the gear C' by which the governor is operated. E is a
plunger or thrust rod at the centre of the shaft B. It revolves in a step which is
pivotally attached to the end of the short arm F' of the lever E.
Connected to the end of the long arm F is suspended a weight or weights F³:
G is a spring which is preferably provided with means G³ for varying its initial
tension.
The hub of governor case D and the shaft B are slotted at c for the passage of
the cable or band H³ and cross-bar Z. H represents the flying weights pivoted
ath to the case, and at their free ends connected by rods II with the eccentric
sleeve C, so that, as the motion of the weights is accelerated and by their centri-
fugal action they recede from the shaft, they will in the usual way operate to
slightly turn forward the sleeve C, or in the reverse direction should the speed
decrease, and vary the relative position of the eccentric C which governs the
cut-off valve.
His a cable or band preferably of steel which is secured to the weights and
extending radially towards the centre it passes over pulleys or quadrants H and
through the slots cover the cross-bar where it exerts à longitudinal pressure
against the plunger rod E.
The operation of the device is briefly as follows:
The weights F are increased or diminished to correspond with the required
speed:
Now should the speed relax, the weights F³ assisted by the spring G will
respond instantly, draw back the flying weights toward the shaft: rotate the
eccentric B thus giving more steam to the engine, and will thereby restore within
a very small fraction of a revolution the normal speed..
The spring G is of such tension that it will exactly compensate for the increase
or decrease of centrifugal force as the flying weights increase or decrease their
radial distance. It is thus seen that the mechanism for bringing the flying
weights back towards the shaft, or in other words for exciting the requisite
centripetal force, is practically stationary beneath the engine and does not revolve
with the weights. It therefore always operates under like conditions and without
danger of becoming disordered whereas in those constructions that carry the
centripetal mechanism in the case with the flying weights, its ability to respond is
measureably varied as the speed varies; and the apparatus is very liable to get
out of order.
Thus. avoiding the use of the usual centripetal springs and the necessity of
maintaining so high and distinctive an initial tension upon such springs.
By this apparatus one is also enabled to readily change the speed while under
motion by simply adding or subtracting weights at F and the disposition of the
weights beneath the engine as shown is also very convenient.
It should be understood that the invention is not confined to a spring G for the
purpose described but that any device may be employed which will operate in

page_text: combination with the weights F³ and yield a variable centripetal force which, shall
compensate for the increased or decreased centrifugal force of the flying weights as
their radial distance is varied."
For instance instead of the spring G the well F might be partially filled with
liquid so that the increased or decreased buoyancy, as the weights F³ are immersed
to a greater or less degree, would accomplish the same end; or the end of the
arm E may be provided with a spiral bearing for the cable f³ so that as the
weights rise or fall the lever arm F2 will be correspondingly lengthened or shortened
and so compensate as above explained.
The liquid or the spring however is preferable rather than the varying lever arm,
since the latter might communicate a pendulous movement to the weights F³. So
also the same effect of the spring G might be accomplished by causing the arm F2
to lift, in addition to the weights, a chain, several links of which rest upon the
floor beneath so that the resistance of the chain would vary with the number of
links suspended above the floor,
It should also be understood that the invention is not confined to any peculiar
arrangement of the flying weights nor to any particular means for communicating
their centrifugal action to the weights F³.
Having now described this invention as communicated to me I wish it to be
understood that what I claim is :-
1st In a governor, the combination with a shaft arranged to operate a main
steam supply valve of a sleeve and eccentric arranged to rotate upon said shaft, a
pair of flying weights pivoted to a support projecting from said shaft, means for
communicating a rocking motion to said sleeve from said weights, a thrust rod
arranged loosely and centrally within said shaft, means for imparting a longitudinal
motion to the thrust rod from the weights, and a variable resistance arranged to
oppose the thrust of the thrust rod substantially as described.
2nd The combination with the centrally bored shaft A, carrying the eccentric for
operating the main valve, of the sleeve C surrounding said shaft and provided with
means for receiving rotary motion, the casing D, fixed upon said shaft, the flying
weights pivoted in said casing, the thrust rod E, arranged centrally within said
shaft, means for communicating a rocking motion from said weights to said shaft,
and a longitudinal movement from said weights to the thrust rod, the lever F
having its end provided with a step in which said thrust rod turns, and means for
opposing a variable resistance to the movement of said lever substantially as
described.
3rd The combination with the lever F, having the step on one arm and a weight
attached to the other arm, the thrust rod having one end in said step, the flying
weights and means, substantially as described, for transmitting motion from said
weights to the eccentric on the shaft and to said thrust rod of adjustable means
for automatically varying the resistance of the said lever to the thrust of. said
thrust rod.
In witness whereof I the said William Phillips Thompson have hereunto
set my hand and seal this Twentyfirst day of October in the year of
our Lord one thousand eight hundred and eighty two