IMPROVEMENTS IN GOVERNORS FOR CONTROLLING STEAM ENGINES OR OTHER MOTORS DRIVING DYNAMO MACHINES
Year: 1885

page_text: I PETER WILLIAM WILLANS of Thames Ditton in the County of Surrey
Engineer do hereby declare the nature of my invention for "IMPROVEMENTS
IN GOVERNORS FOR CONTROLLING STEAM ENGINES OR OTHER MOTORS DRIVING
DYNAMO MACHINES " and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:-
This Invention has for its object improvements in governors for controlling
steam engines or other motors driving dynamo machines.
In order to supply an electric circuit for lighting or other purpose it is
frequently convenient to employ dynamos driven by two or more separate steam
engines, it may be at places a considerable distance apart.
Up. to the present time there is not any convenient and reliable method of
governing the speed of the motors under such circumstances so as at once to
maintain the requisite difference of potential between the electric leads and to
ensure that each dynamo does its proper share of the work.
I effect this by the employment in connection with cach motor of a governor
having two separate solenoids the coils of one I connect with the terminals of the
dynamo or with the two points in the circuit between which a constant difference
in potential is desired (the current passing through this will vary with any change
in the difference of potential between these terminals) and the coils of the other
solenoid I introduce between one of the terminals of the dynamo and the main lead
with which the same is connected or in the case of a large current a portion only
of the current might be taken through these coils the main lead being divided for
the purpose. The current through this latter solenoid will then vary with the
amount of work done by the dynamo in question. I connect the cores of these
solenoids by a lever and link or in any other equivalent manner with the valve of
a fluid relay by which movement is given to the throttle valve or other regulating
part of the steam engine or motor.
The arrangement is such that so long as the current generated is well within the
limit the governing is effected mainly or entirely by the solenoid which has its coils
between the terminals of the dynamo, as the difference of potential between these
terminals increases, the throttle valve of the engine is closed and as it diminishes
the throttle valve is opened wider so as in the one case to check the engine and in
the other to increase its speed.

page_text: Whilst the engine is thus working the other solenoid produces little or no effect;
it may be that its core is held by its spring against a stop or abutment; but when
the amount of current delivered by the dynamo is as large or nearly as large as it
is safe to permit, the core of this solenoid is drawn further into its coils thereby
moving the lever or parts by which it is coupled with the valve of the fluid relay,
and so causing the throttle valve to be partially closed and the speed of the engine
to be checked notwithstanding that the difference of potential between the terminals
of the dynamo may be less than the other solenoid of the governor has been adjusted
to maintain.
Or in place of the fluid relay I employ an electric relay consisting of a small
electro motor which will rotate in either direction according to the direction of the
current transmitted through it. I gear this motor by means of a worm and worm
wheel or in other convenient manner with the throttle valve of the engine. In
connection with this relay I use a circuit closer having two related parts, one part
is moved by the solenoids or it may be by a single solenoid and the other part is
moved by gearing connecting it with the electro motor and thottle valve or other
regulating part of the engine or motor.
When the normal current is passing in the coils of the solenoid the part of the
circuit closer which is connected with the solenoid will be intermediate between the
contacts of the other part, but without resting on either of them; a movement of
the solenoid brings the two parts together on the one side or the other, and the
circuit is then closed through the electro motor. The movement of the throttle
valve or other regulating part of the engine or motor then takes place and
simultaneously there is a corresponding movement of the second part of the
circuit closer which brings it back to the same position relatively to the first part
which it had at the commencement of the operation. The direction which the
current passes through the dynamo and consequently the direction in which the
throttle valve is moved, that is to say, whether it is opened or closed, depends upon
the direction of the initial motion of the solenoid, and the extent of the opening or
closing depends on the distance travelled by the core of the solenoid.
The electro motor relay can be applied to governors having two solenoids, as
already described or to governors having but a single solenoid.
In order that my said Invention may be most fully understood and readily
carried into effect I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a vertical section of a duplex solenoid governor with hydraulic relay.
a a are the coils of the solenoids which connect the poles of the dynamo or other
points in a circuit between which a constant difference in potential should be
maintained. a¹ is the core of the solenoid, a² is the spring by which it is
suspended. b are the coils of the other solenoid conveying the current from
one pole of the dynamo to the main lead. b¹ is the core of this solenoid and b² its
spring the upward movement of the core b¹ is limited by a stop bx. The spring of
this solenoid is so adapted that it does not yield until the current flowing in its
coils is nearly as great as it is desirable to maintain. c is a lever connecting the
cores a¹ and b¹, from it also is suspended by a rod d the valve e which is a light
tube with four rings el upon it fitting but moving quite freely within the tubular
piston rod f g is a piston fast upon the rod and working in the cylinder h. The
rod passes through the ends of the cylinder by stuffing boxes. i is a passage by
which water from a main or elevated cistern is admitted and constantly supplied to
the cavity around the piston and also by holes bored in the piston to the space c²
between the upper and lower pairs of rings e¹. f¹ and f' are upper and lower ports
through the side of the hollow piston roi f; when the valve is in normal position
these ports are not in communication with the space e² of the valve but when the
valve is shifted away from its normal position one or other set of ports receives
water from this space and conveys it into the cylinder h to one or other end and

page_text: the pressure exerted by this water causes a movement of the piston g. The other
ports are at the same time uncovered to the exhaust and water passes out of the
cylinder by them, it ascends the hollow rod fand passes freely away at f'. k is a
stem connecting the hollow rod in which are the ports f and f2 with the double
ring throttle valve 1. The valve works in a cylinder m. The steam or fluid
actuating the engine or motor driving the dynamo enters at n and passes inward
through the ports m¹ in the sides of the cylinder into the passage o which leads to
the engine; or the flow of the steam may be in the reverse direction. It will be
seen that a downward movement of either solenoid core produces a downward
movement of the valve e and this results in a downward motion of the piston g
which continues until the normal relation of the valve e and its ports f¹ and ƒ³
is restored. The downward movement of the piston pivotally closes the steam
ports m' and checks the engine. On the other hand an upward movement of the
solenoid core a' will result in a like movement of the throttle valve and more steain
is given to the engine, unless indeed the upward movement should be excessive
such as would result from a breakage in the circuit, in such a case the steam would
be cut off from the engine by the steam ports being covered by the lower ring of
the throttle valve l.
It is not essential that the valve e and its ports f¹ and ƒ2 should be both move-
able, the ports may be stationary and the valve e may be connected through a lever
so as to receive from the throttle valve or a part connected therewith a movement
opposite to that which it receives from the solenoid. The relay also may operate
the throttle valve through interposed parts instead of by a direct connection as the
drawing represents-this is sometimes convenient where a long movement of the
throttle valve is desired.
.
Figure 2 illustrates the arrangement of a duplex solenoid governor with an
electro motor relay.
The arrangement of the solenoids is as already described. A contact maker E
with contact pieces E' E' upon it now takes the place of the valve e and upper and
lower contacts F1 and F2 take the place of the ports f¹ and f2.
The contacts F and F are carried upon the screw stem K upon which is also the
throttle valve. The parts E¹ E' and F¹ F2 are shown in the drawing in their
normal positions, that is to say, they are not in contact and the apparatus is at rest,
P is a worm wheel working as a nut on the screw stem K and as this wheel is held
in stationary bearings the stem receives a longitudinal movement when the wheel
is rotated. Qis a worm on the axis of an electro motor and in.gear with P. This
motor is so constructed that it begins to run when a current is passed through its
coils and in a direction dependent on the direction of the current. R R are the
commutator brushes of this electro motor each is connected with an upper contact F
and a lower contact F2.
+ and
are the two main leads and these are coupled
with the pieces E' and E' of the contact maker.
The result of this arrangement is the same as the preceding that the throttle
valve receives a movement proportioned to that of the solenoid core. I use a like
arrangement of electro motor relay with a single solenoid.
I would remark that electro motors have before been employed to move thottle
valves and like parts but not so combined with a solenoid that the movement of
the solenoid gives rise to a proportioned motion of the motor and regulating
mechanism of the engine.
I have described the governor as one used for regulating the speed of an engine
driving one dynamo. If the engine or motor drives two or more dynamos the coils
of the solenoids b b might be traversed by the whole or a portion of the current
generated by the group of dynamos.
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. My improvements in governors for controlling steam engines or other
motors driving dynamo machines consisting in the employment therein of two

page_text: separate solenoids connected through levers and links or other intermediate parts
with the valve or contact maker or equivalent part of a relay by which the throttle
valve or other regulating part of the steam engine or motor is operated, one of such
solenoids having its coils between the terminals of the dynamo or between any
other two points in the circuit between which it is desired to maintain a constant
difference of potential, and the other having its coils interposed between one
terminal of the dynamo and the electric lead with which this terminal is connected
substantially as described.
Second. The combination in an electric governor of a solenoid, an electro motor
geared with the throttle valve or other regulating part of the engine or motor, and
a two part circuit closer, one part moved by the solenoid, and the other part moved
by the electro motor, the whole being so arranged that the activity of the electro
motor or electric relay depends upon the disturbance of the normal relative positions
of the two parts of the circuit closer by the movement of the part connected with
the solenoid and that thus a movement of the electro motor is brought about which
restores the normal relation between the two parts of the contact maker as herein
described.