Improvements in or connected with Electric Automatic Regulating or Controlling Apparatus.
Year: 1896

page_text: Date of Application, 8th Sept., 1896
Complete Specification Left, 23rd June, 1897-Accepted, 4th Sept., 1897
PROVISIONAL SPECIFICATION.
Improvements in or connected with Electric Automatic Regulating
or Controlling Apparatus.
We ALEXANDER BEWICKE BLACKBURN, Manager of the Electric Construction.
Company Limited of Wolverhampton in the County of Stafford, and WILFRID
L. SPENCE, Civil Engineer of Dunluce, Tettenhall Road Wolverhampton afore-
said, do hereby declare the nature of this Invention to be as follows:-
This invention relates to electric regulating or controlling apparatus, the
object of which is whenever a governing condition or function varies to auto-
inatically effect a corresponding change in another condition, or function. For
example, this Invention may be usefully employed to control the number of
transformers in circuit on a parallel system of electric distribution subject to
variations of load, or the field of a shunt dynamo, so as to produce an effect
similar to over-compounding, or the starting resistance in a motor circuit, an
integrating, or recording, device, an electric motor, or other stearing gear, a
steam engine stop valve, and the like, but the Invention is not limited to these.
It is thus differentiated from the more common form of governor which has
for its object to maintain constant one function notwithstanding variations in
another, as for instance the speed of an engine, or the pressure of a dynamo
under changes of load.
An arrangement for the purposes of this Invention may consist of a solenoid
and spring-supported core operating two sets of electrical contacts and forming
a controller by which an auxiliary motor (furnishing the power to operate the
regulator) is started, stopped and reversed.
The spring which supports the core is not suspended from a fixed point, as
in the ordinary form of electrical governor, but its support is arranged with a
traversing motion obtained from some portion of the gearing driven by the
motor, and further the travel of the core, under the action of the solenoid is
confined within small limits by the electrical contacts, or by fixed stops, so that
their relative positions do not materially alter. Any variation in the strength
of the governing current immediately brings one, or other, set of contacts into
play. An increase will, say, draw down the core upon the lower stops and start
the motor in a positive direction: this causes the traversing attachment to recede
from the solenoid, and elongate the spring, the motor continuing to run and work the
regulator until the balance is obtained between the opposing forces when the
contact is broken and the motor stopped. A diminution of current releases
the core which is raised by the spring against the upper contacts, so that the
motor is started in the negative direction, and the traversing support is caused
to approach the solenoid until the reduced tension of the spring balances the
diminished force of the current, at which moment the contacts will again be
broken and the motor stopped.
By thus retaining the core continually at the point of greatest sensitiveness,
the range of the apparatus is largely increased, and the method of obtaining a

page_text: balance by traversing the remote end of the spring has the further advantage of
affording means for instantly throwing the mechanism out of gear when the
necessary effect has been obtained.
It is not essential for the core and spring support to have a rectilinear motion.
They may for example be designed to produce a couple about an axis, in which
case a spiral opposing spring will be suitable. Such an arrangement would be
especially applicable for example for a controller gear at sea.
The form of motor may vary with the work to be done. Where the work is
light, such for example as operating a switch, or set of switches, a reciprocating
mechanism of the make and brake type will be suitable. One, or more, of these
may be employed in connection with an electro-magnetic clutch for reversal of
the motion. The clutch is preferably of the shell or iron-clad type with a disc
armaturè oscillated by a connecting rod from the reciprocating mechanism, the
stationary exciting and demagnetising coils being concentric with the shell
and supported by pillars projecting through slots in the oscillating disc.
For heavier work the usual form of rotary motor is suitable, and the solenoid
controlled contacts may then be used merely as a relay to operate the main
switches. In such cases it will be desirable to use another automatic controller
in the armature circuit of the motor for cutting out resistance as the electro-
motive force on the brushes rises and conversely for inserting resistance when
the pressure falls, or the current is cut off.
Where the apparatus is used only as a transmitter, or regulator, controlled by
hand, as for example in an electric motor steering gear, no auxiliary motor is
necessary, the traverse motion for the spring support being obtained direct from
some portion of the main rudder gear. Variations in the solenoid current for
controlling purposes can then be provided for by the insertion, or withdrawal,
of resistance, or (to compensate for alterations in the standard pressure) by a
differential resistance arrangement with two windings in the solenoid.
In general 'only one motor need be used except in those cases where the motion
to effect the regulation, or control, must precede movement of the principal motor;
for example in electric elevator controllers.
Datod this 8th day of Santambar 1906
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields London W.C., Agents.
Improvements in or connected with Electric Automatic Regulating
or Controlling Apparatus.
We, ALEXANDER BEWICKE BLACKBURN, Manager of The Electric Construction
Company Limited of Wolverhampton in the County of Stafford and WILFRID
L. SPENCE, Civil Engineer of Dunluce, Tettenhall Road, Wolverhampton
sforesaid, de hereby deare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement:-
For
This Invention relates to electric regulating, or controlling, apparatus, the
object of which is, whenever a governing condition, or function, varies, to auto-
matically effect a corresponding change in another condition, or function.
example this invention may be usefully employed to control the number of
transformers in circuit on a parallel system of electric distribution subject to
variations of load, or the field of a shunt dynamo so as to produce an effect
similar to over-compounding, or the starting resistance in a motor circuit, an

page_text: a
integrating, or recording, device, an electric motor, or other steering gear,
steam engine stop or throttle valve, and the like, but the invention is not limited
to these.
It therefore differs from the ordinary governor which merely maintains
constant one function notwithstanding variations in another function; as for
instance the speed of an engine, or the pressure of a dynamo, under changes of
load.
An arrangement fort he purposes of this invention may consist of a solenoid
(around which the governing current passes) and a spring-supported core operat-
ing two sets of electrical contacts and forming a controller by which an auxiliary
motor (furnishing the power to operate the regulator) is started, stopped and
reversed. The spring which supports the core is not attached to a fixed point, as
in the ordinary form of electrical governor, but its support has a traversing
motion obtained from some portion of the gearing driven by the auxiliary motor,
and the movement of the core, under the action of the solenoid, is confined
within small limits by the electrical contacts, or by fixed stops, so that the
relative positions of the core and solenoid do not materially alter. Any variation
in the strength of the governing current immediately brings one or the other
set of contacts into play. An increase in the governing current will, say, draw
down the core upon the lower contacts and start the auxiliary motor in a positive
direction; this causes the traversing attachment to the spring suspending the
core to recede from the solenoid, and elongate the spring, the auxiliary motor
continuing to run and work the regulator until a balance is obtained between the
opposing forces, when the contact is broken and the auxiliary motor stopped.
A diminution of current releases the core which is raised by the spring against
the upper contacts, so that the auxiliary motor is started in the negative direction,
and the traversing support of the spring is caused to approach the solenoid until
the reduced tension of the spring balances the diminished force of the current,
at which moment the contacts will again be broken and the auxiliary motor
stopped. By thus retaining the core continually at the point of greatest
sensitiveness the range of the apparatus is largely increased, and the method of
obtaining a balance by traversing the remote end of the spring has the further
advantage of affording means for instantly throwing the mechanism out of gear
when the necessary effect has been obtained.
It is not essential for the core and spring support to have a rectilinear motion.
They may for example be designed to produce a couple about an axis, in which
case a spiral opposing spring will be suitable. Such an arrangement would be
especially applicable for example, for a controller gear at sea.
The form of the said auxiliary motor may vary with the work to be done.
Where the work is light, such for example as operating a switch, or set of
switches, a reciprocating mechanism of the make-and-break type will be suitable.
One, or more, of these may be employed in connection with an electro-magnetic
clutch for reversal of the motion. The clutch is preferably of the shell or iron-
clad type with a disc armature oscillated by a connecting rod from the
reciprocating mechanism, the stationary exciting and demagnetising coils being
concentric with the shell and supported by pillars projecting through slots in
the oscillating disc. For heavier work the usual form of rotary motor is suitable,
and the solenoid controlled contacts may then be used merely as a relay to
operate the main switches.
In such cases it may be desirable to use another automatic controller in the
armature circuit of the main motor for cutting out resistance as the electro-
motive-force on the brushes rises, and conversely for inserting resistance when
the pressure falls, or the current is cut off.
When the apparatus is used only as a transmitter, or regulator, controlled by
hand, as for example, in an electric motor steering gear no auxiliary motor is
necessary, the traverse motion for the spring support being obtained direct
from some portion of the main rudder gear. Variations in the solenoid current

page_text: for controlling purposes, can then be provided for by the insertion, or withdrawal,
of resistance, or, (to compensate for alterations in the standard pressure) by a
differential resistance arrangement with two windings in the solenoid, or a
properly calibrated ammeter may be used in conjunction with the controlling
switch more fully described with reference to Figure 4 this latter arrangement
having the advantage of being entirely independent, within wide limits, of
alterations of the standard pressure as the ammeter, and not the resistance
switch handle then forms the helm or position indicator.
In general only one motor need be used except in those cases where the motion
to effect the regulation, or control, should precede movement of the principal
motor for example, in electric elevator controllers.
Figure 1 of the accompanying drawings shews diagrammatically the general
arrangement of an automatic controller arranged according to our invention to
insert in, and cut out from, the armature circuit of a motor, resistance in pro-
portion as the electro-motive-force at the brushes falls and rises. A governing
coil G is connected across the armature E M of the motor. F is a shunt field
coil. A spring S is connected at one end to a support carried by a traversing
nut N, the other end of the said spring supporting an iron core I, (or it may be
a permanent magnet or a solenoid) to which is attached a contact bar B or equiva-
lent device. The range of travel of the core I and bar B is limited by fixed
contacts a a b b which act as stops. The nut N is mounted on a screwed
spindle S which obtains its motion in any suitable way either mechanically or
electrically but controlled as to its direction of motion by the circuit made at
a a and b b,. respectively. At the lower portion of Figure 1 is shewn an electro-
magnetic clutch constituting a part of, or connection with, the aforesaid
auxiliary motor and consisting of an iron-clad shell magnet rotatable with the
vertical spindle S* and provided with magnetising and demagnetising coils M
and M. These coils are fixed and supported by pillars P projecting through
slots or holes H H (Figure 2) in an iron dise D, which is mounted loosely on the
screwed spindle S, and which, in operation, is oscillated through a small angle
by any suitable means. A convenient arrangement for operating the disc Dis
illustrated in Figure 3, and consists of a modified construction of trembling bell
mechanism.
The electro-magnets e eff and gghh are arranged as shewn, each being
wound with magnetising coils e e, and h h, and with demagnetising coils f f
and g g the swinging armature A A¹ of these magnets are connected by links A
to the disc D so that movement of the armatures oscillates the said disc D.
Contacts C C are arranged to complete the demagnetising circuit through the
coils ffgg when the armatures approach the cores, as will be understood by
those familiar with this class of mechanism. The circuits of the coils M M' of
the clutch are connected as shewn, and the action is as follows:-
When the motor E M Figure 1 is switched on the supply circuit, the nut N
is at the bottom of its travel on the screwed spindle S* and the whole of the
resistance R (which just allows the necessary starting current to pass) is in the
circuit. As the motor gets under way the electro-motive-force at the brushes
rises, which has the effect of drawing down the core I so that the bar B makes
the lower contact a a thereby magnetising the rigth hand magnets (Figure 3)
by the coils and the clutch by the coil M', the armature A is attached and
imparts through the disc D a partial rotation to the clutch and spindle S. As
the stroke approaches completion the contact C is made and the magnet and
clutch are de-magnetised by the coils y a and M respectively, the armatures are
released and are returned under the action of the springs shewn, no motion of
the spindle S being caused on the return stroke.
The cycle of operations continues so long as the electro-motive-force on the
armature brushes E M is rising thereby giving to the hpindle 8 intermittent
partial rotation causing the rut N to rise on the said spindle S and as it rises
to cut out more and more of the resistance R. It will be seen however that the

page_text: rising motion of the nut N causes increased tension of the spring S and this
would raise the core I and bar B, if the electro-motive-force did not continue to
rise so as to maintain the balance between the spring tension and pull of the
solenoid G on the core I. The moment that the motor is switched off, or that the
load becomes so great as to reduce the speed and electro-motive-force across the
brushes, the spring S raises the core I and bar B against the upper contacts bb
thus completing the circuit through the left hand magnet and reversing the
direction of rotation of the spindle S. The nut N is now lowered and
resistance R is inserted into the circuit so that the normal full load current cannot
be exceeded or in case of switching the motor off, the whole of the resistance is
again included.
It is obvious that instead of the resistance R means may be provided for
inserting in the circuit variable electro-motive-force.
It will be seen that this controller is particularly applicable to elevator or
hoist motors, as it is entirely out of the power of the operator to switch on current
too rapidly whilst he can by means of a switch worked by the hand rope switch
off quickly, or slowly, as desired.
It automatically comes into operation upon any change of load, or speed; and
stops immediately the conditions have been properly balanced.
The invention is capable of numerous other applications: For example, the
following may be the arrangement where it is desired to control, in an outlying
sub-station, the number of transformers in circuit under variations of load.
The governing solenoid, or electro-magnet, G, is wound with a series coil
carrying the whole, or a certain proportion of the, current passing through the
sub-station. The traversing nut N will either operate directly a set of switches
placed in line so as to be successively closed, or opened, as they are passed over
by the part operated by the nut N, or the said part so operated may, at certain
points of its travel, make electrical contact completing the circuit of an electro-
imagnet whose armature will pull over, or through a ratchet and pawl gear rotate,
a lever, so as to alternately open and close the corresponding switch.
Another application of very great value in certain cases is the control, at a
distance, of a secondary battery either directly by means of an end cell regulat-
ing switch, or indirectly by means of a booster transformer, whose generating
field can be varied both in strength and direction so as to charge as well as
discharge the battery.
Figure 4 illustrates diagramatically the application of our invention as a
transmitter in connection with a hand controlled steering gear.
The governing solenoid G, core I, spring S bar B and contacts a ab & operate
ns hereinbefore described. The solenoid G is, however, in this case, controlled
by hand through a combined rheostat and helm indicator, W. A reversing
switch R. S. is operated by one, or other, of the electro-magnets, shewn at X, Y.
E M is an electro-motor, driving, through worm gear, the chain c* and slider B*
connected to the rudder H. No auxiliary motor is required in this case, the
spring S being supported by a connection with the rudder chain at s or by any
other convenient part of the gear which moves in correspondence therewith.
The rheostat in the helm indicator W is in series with the solenoid G which is
therefore controlled by its movements.
The circuits of the electro-magnets X, Y, of the reversing switch R S are
shewn as being simply made and broken at a and b, but they may obviously be
arranged with demagnetising coils as in Figure 3, so as to minimise sparking at
the contacts. The connections of the reversing switch and motor armature are
clearly shewn. The field-coil is not shewn. It may be a shunt with constant
excitation. An auxiliary controlling gear is indicated at C G for regulating the
motor starting resistance as already described. The action is as follows:-
A movement of the contact in the helm indicator W to one side (say starboard)
will cut out resistance, the solenoid G will draw down the core I, the contacts a
will be made, the magnet Y excited and the reversing switch be thrown over to

page_text: the left hand contacts. The motor E M will be started in the direction (by
proper connection of the field to haul the chain C and slide B to the right
putting the helm over to starboard. The motor E M will continue to run until
the tension of the spring S is increased sufficiently to balance the attraction of the
solenoid G when the contacts will be broken and the swintch R S drawn to
the neutral position by a spring in connection therewith. On the other hand if the
contact in the helm indicator W be moved over to port, resistance is inserted,
the solenoid G releases the core I, the contacts are made, the magnet X is
excited, and the reversing switch R S is thrown on to the right hand contacts y.
The motor will now run so as to haul the chain C and the slide B to the left
putting the helm over to port. It will continue in this position until the tension
of the spring S is so far reduced as to break the contacts b b and cause the main
traversing switch R S to be drawn over, by its spring, to the neutral position.
It will be readily understood that the apparatus in accordance with our inven-
tion may be modified as regards details, and therefore we do not confine ourselves
to the actual details described and illustrated, for instance, the spring-supported
core may have a circular motion about an axis; the solenoid may he replaced by
an electro-magnet, and the core by a solenoid, a permanent magnet, or by another
electro-magnet. The spring may be replaced by a weight acting with a variable
leverage, the contacts by a mechanical clutch lever, the screwed spindle by a
toothed rack and gears, or by a plain spindle moving a contact maker over contacts
by a circular motion, in which case a cord, or band, wound on the spindle, would
give the necessary attachment for the spring, but in any case the traversing
attachment for the spring, or its equivalent, should be controlled, as
to the direction and duration of its motion, by the small relative movement
between a solenoid and its core (or the equivalents thereof), and the apparatus
should remain in action so long as the solenoid, (or its equivalent), and opposing
force do not balance, and the principal action stop so soon as the balance is
attained.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is :-
1. An electric regulating or controlling gear arranged to operate substantially
as hereinbefore described, and for the purposes hereinbefore indicated, or for
analogous purposes.
2. An electric regulating, or controlling, gear consisting of a solenoid, or
electro-magnet, spring opposed core, or armature, contacts made and broken by
the same, and controlling an electric motor, or an electro-magnetic clutch, a
traversing attachment for the spring, deriving its motion from the controlled
motor, or clutch and switches, or other devices, operated thereby; all
substantially as hereinbefore described.
3. In an electric regulating or controlling gear a traversing attachment for the
spring or the equivalent by which without considerable movement of the core,
or armature, but governed thereby the force of the spring or the equivalent is
made to counteract the changing force of the solenoid, or electro-magnet, and to
break the circuit of the working motor relay or clutch when a condition of balance
has been restored, substantially as, and for the purposes hereinbefore described.
4. An electric regulating, or controlling, gear, consisting of a solenoid, or
electro-magnet, a core, or armature, provided with a spring opposing the action
of the solenoid, or electro-magnet, contacts made and broken by the movements
of the said core, or armature, and controlling a motor reversing switch, or an
electro-magnetic reversing clutch, the said spring being connected with a travers-
ing attachment deriving motion from the controlled gear and a variable
resistance, or its equivalent, in circuit with the solenoid, the whole operating
substantially in the manner, and for the purposes, hereinbefore described.
5. In an electric regulating or controlling apparatus, the clutch gear, consist

page_text: ing of a vibrating iron disc, or its equivalent, a magnet of the shell type, and
exciting and demagnetising coils supported by pillars projecting through slots
in the disc; substantially as hereinbefore described.
6. In an electric regulating or controlling gear the combination of the motor
and the driving clutch, substantially as described and illustrated by Figures 1, 2
and 3 of the accompanying drawings.
7. The application of an elect: c controlling gear, substantially as herein before
described, to regulate, or adjust, at a distance from the controlling point, the
position of a body such for example as a switch bar, a rudder, a gun, a signal,
or a valve.
Dated this 23rd day of June 1897.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.