Improvements in Electrically Driven Fans.
Year: 1899

page_text: Date of Application, 10th June, 1899
Complete Specification Left, 21st Feb., 1900-Accepted, 31st Mar., 1900
DE MULTIVAL
Improvements in Electrically Driven Fans.
I, WILLIAM HARDING SCOTT, of Gothic Works, Norwich, in the County of
Norfolk, Engineer, do hereby declare the nature of my invention to be as
follows:-
This invention relates to electrically driven fans, especially suitable for use
for ventilation and forced draught on board ship where it is desirable that the
motor should be perfectly enclosed and watertight.
In order to shorten the motor and carry it as far into the centre of the fan
as possible to get the best cooling action I use either a multipolar, or a gramme-
ring, armature, as, with either of these, the bearing can be carried up into the
centre of the armature.
As the power required to drive one of these fans decreases very rapidly in
proportion to decrease of speed, it becomes practicable to use an extension of
the series-parallel system of connecting the field magnets for starting and con-
trolling, and my controller, together with the way it is arranged on the frame of
the motor, forms a simple method of connecting up four separate coils, or parts
of coils, either all in series, all in series-parallel, or all in parallel; a double pole
switch completely disconnecting the motor from the electric circuit can also be
included in the same mechanism. The ends of the four coils, or of the four parts
of the coil, as well as the brush connection and the terminals for main leads, are
all connected to two parallel rows of spring connections. Between these parallel
rows I place the controller drum, or cylinder, which has metal contacts fixed to
its surface, properly insulated, in such a way that, at the first, or off, position,
none of the spring connections touch any of the drum, or cylinder, contacts,
and the whole motor is disconnected except the actual terminals. On the second
position the spring connections touch certain of the drum contacts which are
arranged in such a way that all the four magnet coils are in series, on the third
position the drum contacts are so arranged that the four coils are two in series
and two in parallel and on the fourth position the four coils will be all in
parallel. In every case, except the first, the coils are in series with the armature.
The fan works well, and without excessive heating, or any material disarrange-
ment of the proper working conditions, in each of the three cases.
If the controller were fixed separately from the motor the connection would be
very complicated but by placing the controller in a box cast, or secured, to
the motor framing and communicating by an opening with the interior of the
motor I can take the connections direct from the coils to the controller and do
all the connecting between the controller and the different parts of the motor
in the factory. The controller is properly boxed in with preferably a separate
cover.
Dotad this 11th Jon of Tunn 1000

page_text: I, WILLIAM HARDING SCOTT, of Gothic Works, Norwich, in the County of
Norfolk Engineer, do hereby declare 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:-
This invention relates to electrically driven fans especially suitable for use
for ventilation and forced draught on board ship where it is desirable that the
motor should be perfectly enclosed and water-tight.
I will describe my invention with reference to the accompanying drawings
wherein Figure 1 represents partly in side elevation, and partly in longitudinal
section, an electrically driven fan constructed according to my invention and
Figure 2 is a transverse section of the same Figs. 3 and 4 are vertical sections
at right angles to each other of the speed controlling device and Figure 5 is
a diagram shewing the electric contacts of the controlling device in connection
with the motor.
In order to shorten the motor A and carry it as far into the centre of the fan B
as possible to get the best cooling action I use either a multipolar or a gramme
ring armature as, with either of these, the bearing 6 can be carried up into
the centre of the armature a. As the power required to drive one of these fans
decreases very rapidly in proportion to decrease of speed it bcomes practicable
to use an extension of the series-parallel system of connecting the field mag-
nets C, for starting and controlling, and my controller, together with the way it
is arranged, on the frame of the motor, form a simple method of connecting up
four separate coils D, or parts of coils, either all in series all in series parallel or
all in parallel a double pole switch completely disconnecting the motor from
the electric circuit can also be included in the same mechanism. The ends of
the four coils D, or of the four parts of the coil, as well as the brush connection
and the terminals for the main leads are all connected to two parallel rows of
spring connections dd. Between these parallel rows I place the controller
drum or cylinder E which has metal contacts e fixed to its surface properly
insulated in such a way that at the first or off position as shewn in the diagram
none of the spring connections touch any of the contacts c of the drum or
cylinder E and the whole motor is disconnected except the actual terminals.
In the second position the spring connections touch the rows of contacts
marker II on the drum or cylinder E which contacts are arranged in such a
way that all the four magnet coils D are in series. In the third position corre-
sponding to that marked III in the diagram contacts e on the drum or cylinder
touch such of the spring connections d d that the four coils 1) are two in series
and two in parallel and in the fourth position corresponding to that marked IV
in the diagram contacts e on the drum or cylinder E touch such of the spring
connections & d¹ so that the four coils D will be all in parallel. In every case
except the first the coils D are in series with the armature a. The fan works
well and without excessive heating or any material disarrangement of the
proper working conditions in each of the three cases. If the controller were
fixed separately from the motor the connection would be very complicated but
by placing the controller in a box F cast or secured to the motor framing and
communicating by an opening f with the interior of the motor casing I can
take the connections direct from the coils to the controller and do all the con-
necting between the controller and the different parts of the motor in the factory.
The controller is properly boxed in with preferably a separate cover G.

page_text: Having now described and particularly ascertained the nature of this
invention and in what manner the same is to be performed I declare that what
I claim is;
1. An electrically driven fan provided with a motor having the fan bearing
projecting into its centre and a series-parallel system of connection of the field
magnets and a controller in a box cast or secured to the frame of the motor and
arranged so that contacts can be so made that either the motor is disconnected
or the coils are in series or in series-parallel or in parallel substantially as here-
inbefore described.
2. The combination in an electrically driven fan of a motor and controller
arranged substantially as herein before described.
3. The combination of parts constituting an electrically driven fan as herein-
before described and illustrated in the accompanying drawings.
Dated this 21st day of February 1900.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.