IMPROVEMENTS IN THE ELECTRICAL REGULATION OF STEAM AND OTHER POWER ENGINES AND PUMPS, AND IN APPARATUS TO BE USED THEREFOR."
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Arthur William Lovell Reddie at the
Office of the Commissioners of Patents on the 5th September 1882. Com-
municated to him from abroad by Alexander Krásza and Josef Schaschl both
of Gratz in the Empire of Austria.
ARTHUR WILLIAM LOVELL REDDIE of the Office for Patents 66 Chancery Lane
in the County of Middlesex, Patent Agent "IMPROVEMENTS IN THE ELECTRICAL
REGULATION OF STEAM AND OTHER POWER ENGINES AND PUMPS, AND IN APPARATUS
TO BE USED THEREFOR."-[Communicated to him from abroad by Alexander Krásza
and Josef Schaschl both of Gratz in the Empire of Austria]
The operation of the electrical regulator which forms the subject of the present
invention is based upon the effect produced by a coil of wire or solenoid, when a
current is passed through it, upon a rod of iron.
This effect as is well known is to cause the iron rod to be drawn within the coil
and held fast therein, so soon as the midway points of the axes of the rod and the
solenoid respectively coincide.
If the rod be subjected to the action of two solenoids suitably placed with respect
to the iron bar, and an electric current be passed alternately through the solenoids
the rod will receive a reciprocating motion.
If now two such iron rods or bars are affixed to the sides of a valve and the
solenoid is suitably adapted thereto, it is clear that the motion of the valve will be
dependent upon the time of the entry, and the duration of the action of the electric
current, which will be alternately sent through the coils.
The timing of this action will be regulated by current dividers of known
construction, the proper position of which (according to circumstances) will be
ensured by fixing the same on the main shaft (or on an auxiliary shaft) of the
engine (as for instance in locomotives, marine engines, pumps, blowers and the
like), or for the purpose of regulating expansion, will be brought automatically
into position by means of governors.
The valves in disc-valve steam engines and pumps will be operated by means of
iron spindles, whilst clack valves, cocks, and rotary valves may be operated by
means of iron rods specially adapted thereto, and set in action by means of the
electric current passing through the solenoids.
The electric current may be obtained from any source of electricity or it may be
delivered from a dynamo electric machine which may be driven either by the

page_text: engine to be regulated or by an auxiliary motor. As, however, an electric current
must be ready to hand in order to start the machine in the first place, this should
be obtained by means of an auxiliary motor which may be dispensed with later,
or the current required in the first instance may be taken from a Faure battery.
When the steam engine and with it the electric machine brought into action, a
small portion of the current generated by the electric machine is led into the Faure
battery until it is again fully charged.
In applying the invention to a disc valve steam engine the inlet and outlet
valves are situated near each other; one pair of such valves at each end of the
cylinder. Between each pair of valves is fixed an upright having two vertically
adjustable cross pieces carrying solenoids which surround the valve rods. A flat
metal spring is fixed at its centre to the top of the upright, and is adjustably
connected by screw nuts with the ends of the valve rods, so as to operate the same
either by tension or pressure.
By suitably adjusting the arms which carry the solenoids, or by equivalent means,
the action of the valves may be precisely regulated.
The current divider consists of two discs and a drum of non conducting material
on which are fixed contact plates of copper or other good conductor.
Against the contact discs and the drum rub brushes of copper wire from which
conducting wires lead to the solenoids. The other ends of the solenoid coils lead to
a common return wire connected to one pole of the dynamo, or other source of
electricity, whilst the contact discs and current distributing drum above referred
to are connected by a spring with the other, or positive, pole of the electric
generator.
The discs are connected rigidly to the spindle of the rotary governor and as they
serve to lead the current to the solenoids of the exhaust valves, their operation is
not variable; whereas the drum is mounted on a sleeve and is always held in such a
position by the action of the governor that the duration of contact of the brushes
will correspond to the degree of expansion required.
The copper contact surfaces on the drum are so disposed that as the drum is
raised or lowered on the governor spindle, the position of the fixed brushes with
respect to the contact plates will be varied, and the effect of this on the solenoids
will be that the electric current will excite them for a longer or a shorter time.
دو
If desired the brushes may be made movable according to the motion of the
governor, and the drum be made rigid. By this arrangement instead of using the
slowly rotating Watt governor the more sensitive governors known as the
"Cosine" or "Porter governors may be employed. The current dividing drum
can then be arranged vertically or horizontally. It is only necessary that it should
make the same number of revolutions, or an aliquot part thereof, as the engine to be
regulated. In the latter case the number of sets of contact plates must be made to
correspond.
This electric system of regulation offers at least the same amount of exactitude
as that secured by the best kinds of precision governors, as the operation is
extraordinarily rapid and thus the "steam diagram" of the engine comes very near
to the theoretically perfect. The movement of the valves will not only be very
rapid, but will also be effected without any concussion and without the necessity
of employing for this purpose the usual complicated and expensive arrangement of
link rods which in the best kinds of precision regulators, cost more than a small
dynamo machine. An engine provided with this electric regulator requires,
moreover, scarcely any attention.
In adapting this invention to an ordinary three port slide valve, the said valve is
preferably made somewhat longer than usual, so that the steam which has entered
may act expansively before the exhaust port is closed. The brushes which slide
over the current distributing drum lead the current to the solenoids through
which the valve rods pass in such a manner that first one and then the other in
each pair of solenoids is excited, whereby the valve is moved backwards and
forwards

page_text: In applying the electric precision regulator to locomotive engines perforated or
grid valves are employed, and each cylinder is provided with two inlet and two
outlet valves, a solenoid being adapted to each side of each valve and the current
being passed alternately through that solenoid towards which the corresponding
valve is to be moved.
A current distributing drum of somewhat more elaborate character is required
for the locomotive engine.
It is provided with three distinct sets of contact plates, the collecting brushes
being so arranged that by the movement of a switch lever the current from the
generator may be sent through any one of the three sets. One set of contact
plates is intended for the forward motion of the engine, and on the current being
passed it will be led by the brushes of this set to the proper solenoids for operating
the valves and admitting steam in the sense required. The lower set of plates is
arranged for giving a backward motion to the engine, and the central set of contact
plates is arranged in case it is required to suddenly use the back pressure of the
steam to check the impetus of the engine.
It will be understood that when the solenoid adapted to one side of the valve
becomes operative, the corresponding solenoid on the other side will cease to act,
the electric current having been cut off from the same.
In this arrangement all the brushes are adjustable together, being mounted on
four rods which are connected to, or carried by, a ring or plate of metal. The
brushes maintain their relative positions with respect to each other, while all the
brushes can be adjusted simultaneously to effect any desired degree of expansion.
The current distributing drum with its three sets of contact plates insulated
from each other will derive rotary motion from the driving shaft of the locomotive
engine by means of suitable gearing, and will make the same number of rotations,
or an aliquot portion thereof.
If during work it is required to reverse the engine and check its progress, it will
only be necessary to slightly shift the switch lever twice; the current passing first
through the central set of contact plates on the current distributing drum,
whereupon the main driving wheel will be checked and partially shifted in the
reverse direction; and next through the contact plates corresponding to the
required new direction of motion.
The distribution of the steam in compound or other engines in which these
special requirements must be provided for can obviously be effected by means of
suitably arranged contact plates.
As saturated steam at a pressure of 14 atmospheres has a temperature of less
than 200° C, and as at this temperature the intensity of the electric current is only
slightly diminished it will be possible to pass the wires steam-tight into the
regulator case, and the solenoids merely covered by a jacket of suitable material,
may be arranged in the steam space.
Valve stuffing boxes and packing are thus rendered unnecessary and without
any complication of the form of the steam cylinder an entire jacketing may be so
arranged that even the valve cases themselves may be surrounded by the cylinder
jacket.
The above are given as examples merely, but they will suffice to show the way in
which the invention may be applied to other kinds of engines, and pumps.
In the case of direct acting engines pumps and blowers, the contact cylinders
may be conveniently adapted to the cross head. In other cases they are preferably
adapted to the main shaft.