IMPROVEMENTS IN THE APPARATUS FOR CONTROLLING the speeD OF ENGINES
Year: 1884

page_text: I RALPH HENRY CHRISTOPHER NEVILE of Wellingore in the county of Lincoln
Esquiro do, hereby declare the nature of my invention for IMPROVEMENTS IN THE
APPARATUS FOR CONTROLLING the speeD OF ENGINES to be as follows:-
This invention consists in the application to a governor formed by a core &
solenoid in which the said core is attracted within the solenoid by an electrical
current of an arrangement whereby the pressure of steam in the boiler is made to
assist the said governor in closing the controlling valve in such a way that when
the pressure of steam in the boiler rises it requires less force than would be
otherwise the case to be exerted by the governor to close the valve & consequently
instead of the engine running at an increased speed with a heavier pressure of
steam by properly adjusting the apparatus the speed may be obtained nearly
uniform The method by which this additional force is obtained is a piston
working in a cylinder into one side of which steam is admitted at the boiler
pressure the other side may be open to the atmosphere or if deemed advisable may
be in communication with the steam in the valve chest when a controlling valve is
fixed between the boiler & the valve chest-The same end may also be obtained
by using two pistons & two cylinders acting in contrary directions the one cylinder
being in connection with the steam in the boiler & the other with the steam in the
valve chest-In most cases however the one cylinder in communication only with
the steam in the boiler will prove sufficient-The piston rod or rods are so arranged
as to press either directly or by a system of levers upon the core of the solenoid
in such a manner that when the steam in the boiler rises or when the difference of
pressure between the steam in the boiler & that in the valve chest increases the
solenoid will attract the core with greater ease & so compensate for the increased
force which would otherwise cause the engine to run faster.
This apparatus may be applied to a governor of the above description whether
it actuates a throttle valve or equilibrium valve controlling the admission of steam
to the steam chest or whether the governor actuates a variable expansion gear but
it is more especially applicable to the former-It is of course especially applicable
to engines driving dynamo electric machines as the current for the electrical
governor may then be derived from the main machine but it can also be used for
TD 077

page_text: engines driving other machinery by using a small dynamo electric machine driven
by the engine specially to furnish the necessary current for the electrical Governor.
The mechanical details of the apparatus may of course vary and the size of the
cylinder or cylinders will of course do so in each case to suit the special controlling
arrangement of the governor-The main feature of the invention being the
application of a piston or pistons actuated either by the steam pressure from the
boiler alone or by the difference of steam pressure between the boiler & valve chest
to assist an electrical governor of the type above described in controlling the
engine & keeping it at the same speed under varying heads of steam. When the
Electrical Governor is used to maintain a current either of constant quantity or of
constant electro motive force from a dynamo machine with varying speed of
engine the same apparatus will also apply the quantity or electro motive force as
required being maintained more constant than it would otherwise be under varying
pressures of steam.
I RALPH HENRY CHRISTOPHER NEVILE of Wellingore in the county of Lincoln ?
Esquire do hereby declare the nature of my invention for IMPROVEMENTS IN THE
APPARATUS FOR CONTROLLING THE SPEED OF ENGINES and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention consists in the application to a governor actuated by electricity 2
of an apparatus whereby the action of the said electrical governor may he kept
uniform during variations of steam pressure in the boiler or generator and also
during variation of the work done by the engine or motor which the governor
controls. The drawings attached hereto show two ways in which this may be
effected in Figures 1 & 2 are shown one of Richardsons electrical governors 3
cousisting of two solenoids A A¹ & B B¹ within which are two iron cores C C' & D D'
these are actuated by the influence of the electrical current passing through the
solenoid in such a manner that when the current increases the cores are drawn up
raising the long arm of the lever E the short arm thereof being then caused to
press down upon the spindle of the valve and thereby partially to close it-In 3
Figure 1 I prolong the spindle of the valve upwards allowing the short arm of the
lever to work in a slot therein and upon the top of the spindle I place a roller F
which may be of steel, Phosphor Bronze or other suitable material-A lever G. H.
with fulcrum at K is arranged on any suitable stand one arm of this lever presses

page_text: upon the roller F and upon the other arm of the lever a piston rod M furnished
with a cap and small roller L acts. This piston rod is connected to a piston N and
this works in a cylinder and to this cylinder on the under side of the piston steam
is admitted from the boiler-The space above the piston may be in communication
with the atmosphere or it may be in communication with the steam chest or steam
space on the side of the regulating valve furthest from the boiler-The action is as
follows when the boiler pressure rises or when the difference between the boiler
pressure and steam chest pressure increases the piston N is pressed upwards & this
acting on the piston rod M and lever G H tends to press down and close the
regulating valve thereby assisting the solenoid in the work it has to perform--The
Bize of the Piston N and the relative distances of the roller F and the roller L from
the fulcrum & must be adjusted in accordance with the species of the regulating
valve used (in the form of valve shown in dotted lines upon the drawing and
known as a double beat Cornish valve these proportions will depend upon the
respective areas of the upper and lower valve face and the area of the valve
spindle). This is easily determined by ascertaining by experiment the different
pressures exerted upon the valve by different pressures of steam in the boiler &
calculating the area and ratio of leverage in accordance with the data thus
obtained-By properly adjusting these it may be arranged that the quantity of
current passing through the solenoid to operate the regulating apparatus will be
almost precisely the same whatever be the boiler pressure. If required a weight
may be hung upon the lever G H at or near the point this may in some cases
be necessary to prevent the force exerted by the piston N entirely closing the
regulating valve the amount of this weight is best ascertained by experiment-In
Figure 2 the same description will apply but the cylinder and piston is in this case
placed upon the other side of the fulcrum and as the boiler pressure rises tends to
raise the cores of the solenoids instead of acting directly upon the valve spindle.
In this case F is a roller upon the end of a bar which is attached to the cross piece
connecting together the two cores, In other respects the same description applies
to both.
It will be seen that the principle is the same in both cases as in the latter case
the compensating force is transmitted through the lever which is attached to the
cores of the solenoid, to the valve spindle.
It will be understood that I do not restrict myself to the particular governor
described or to the particular method of attachment or transmission of the power
obtained by the piston which forms are used as an illustration of the method in
which it may be applied and which can be varied according to the form of the
governor and to meet any special requirements. Nor do I confine myself to the
use of one piston & cylinder only as I can also use two cylinders and pistons
the upper parts of both cylinders being in communication with the atmosphere and
the lower part of one cylinder being in communication with the steam in the boiler
and the lower part of the other in communication with the steam on the side of
the regulating valve further from the said boiler-In this case the two pistons
would act upon the lever H but one will act upon one side and one on the other
side of the fulcrum K or they may both act upon the same side and one of them
be inverted to act in a contrary direction-I may also use instead of pistons and
cylinders as above described any apparatus such as two elastic diaphragins between
which the steam is admitted or a coil, coils, or portion of a coil of copper or other
tube into which steam is admitted or any similar suitable apparatus which by ita
tendency to alter its form on variation of internal or external pressure will exert a
force of a similar description to that exerted by the Piston,
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
1st The use in conjunction with an electrical governor acting upon the regulating
mechanism of an engine or other motor of a piston and cylinder the cylinder on

page_text: one side of the piston being in communication with the boiler or reservoir of steam
or other elastic fluid which actuates the said motor and on the other side open to
the atmosphere in such a manner that the force exerted by the piston will act
upon the governor or valve so as to counteract and compensate for the variation
which would otherwise occur owing to the variation of pressure in the said
reservoir of elastic fluid substantially as above described.
2nd The use in conjunction with an electrical governor as described in claim 1 of
a cylinder and piston one side of the cylinder being in communication with the
reservoir of elastic fluid and the cylinder on the other side of the piston being in
communication with the elastic fluid on the side of the regulating valve furthest
from the said reservoir so as to counteract and compensate for the variation which
would otherwise occur owing to variations in the difference of the pressure of the
elastic fluid in the said reservoir and on the other side of the said regulating valve
substantially as above described.
3rd The use in lieu of one cylinder of two cylinders and pistons one actuated by
the elastic fluid in the reservoir and the other by that on the further side of the
regulating valve substantially as described.
4th The use of elastic diaphragms or of a coil, coils, or portion of a coil of copper
or other tube or any such similar apparatus as will by the variation of internal or
external pressure have a tendency to alter its form and so give a similar force in
replacement of the pistons and cylinders as above described.
5th The use of the Electrical governor with the compensating apparatus sub-
stantially as above described.