Improved Means for Ventilating Enclosed, or Partially Enclosed, Electric Motors.
Year: 1898

page_text: Improved Means for Ventilating Enclosed, or Partially Enclosed,
Electric Motors.
I, WILSON HARTNELL, of Volt Works, Kirkstall Road, in the City of Leeds,
Yorkshire, Engineer, do hereby declare the nature of this invention. to be as.
follows:-
I divide the space within the motor into two chambers, and also provide fan
blades which revolve with the armature. The suction side of the blades is 'con-
nected to one chamber, and the delivery side to the other. Both chambers are,
in general, connected to the outside air by means of suitable openings. The
chamber containing the armature and magnet windings may form the delivery
side, the air circulating through it; or this chamber may form the suction side,
in which case the air can be drawn through special openings so as to impinge
upon certain parts such as the brushes, formers, or magnet windings. Air holes
may be made in the magnet poles, or armature spindle; or internal pipes may be
used.
1
In some cases the air openings may be placed in the upper part of the motor,
or connected by pipes to a higher level, or connected to another room or place.
The openings may be protected by surfaces of wire gauze, or other suitable
material, placed outside the motor, easily detached for cleaning. In other cases,
the air holes may be connected to passages containing wire gauze, shot, or other
suitable material, so arranged that air can permeate through, but flammé cannot
pass. Where no connection with the external air is desirable, the air passages may
be connected to a cooling chamber through which the air circulates.
The advantages of these arrangements are that the motor can be cooleil by
mechanical, or forced circulation of air in a most efficient manner.
There is a further advantage in that the ventilation of the motor can be main-
tained under adverse external conditions, such as, liability to be flooded, the
presence of explosive gases, or inflammable particles, the presence of injurious
dust, or fluffy material, or even of an atmosphere which may not circulate
through the motor.
"
23
Thus, by means of this invention, the efficient ventilation of electric motors
can be effected, whether the motors be working in mines, in mills, on tram-cars,
or under any other conditions.
Dated this 14th day of June 1898

page_text: Improved Means for Ventilating Enclosed, or Partially Enclosed,
Electric Motors,
J, WILSON HARTNELL, of Volt Works, Kirkstall Road, in the City of Leeds,
Yorkshire, 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-
I divide the space within the motor into two chambers, and also provide fan
blades which revolve with the armature: The suction side of the blades is con-
nected to one chamber, and the delivery side to the other. Both chambers are,
in general, but not always, connected to the outside air by means of suitable
openings.
In order more fully to explain my invention, I have appended drawings which
are herein described.
In Figs. 1 & 2 the fan (or fan blades) I is placed close to the armature of which
it may form a part. The suction chamber S is connected to the outside air by
means of suitable openings 00-and the delivery chamber D which contains
the armature and the magnet windings by 0, O₁. The circulation of the air is
shewn by the arrows.
י
In Fig. 3, the fan l' is placed apart from the armature. The suction chamber S
in this case contains the armature and the magnet windings, and the delivery
chamber D is connected to the outside air. The circulation of the air is shewn
by the arrows. The air can be drawn in through openings 0, 0, specially arranged,
so that it may impinge upon particular places such as the brushes. Air holes O₁₁
may also be made through the magnets.
In Fig. 4, the air in the motor is not connected to the outside air. The air is
circulated inside by means of the fan F, the suction chamber S and the delivery
chamber D. By means of pipes P, P', it can be made to impinge upon any par-
ticular place such as the armature and commutator.
In Figs. 5 & 6 also, the air in the motor is not connected to the outside air.
The air is circulated inside by means of the fan F, the suction chamber S, and the
delivery chamber 1) and directed, as required, by means of the pipes P, P. The
internal air is assisted to cool the motor by means of the internal pipes P1, P
through which external air is circulated by means of the fan F₁, the suction
chamber S, and the delivery chamber D.
In some cases, the motor may be advantageously connected by pipes (Fig. 7)
to a higher level, such as when the motor is in a place liable to be flooded.
In other cases, such pipes (Fig. 7) may be arranged to draw air from another
place Pr
By this means, although the air surrounding the motor may contain inflammable
particles, injurious dust, fluffy material, steam, or any other impure atmosphere
which should not circulate through the motor; yet the circulation of fresh air
can be provided if pipes can be taken from the motor to a sufficiently pure supply
elsewhere. For example, a tram-car motor can thus be safely ventilated by
drawing comparatively pure air from inside the car.
The openings 0, 0 (Figs. 2, 3, 4, 5 & 6) may be protected by surfaces of wire
gauze, or other suitable material placed inside, or outside, the motor, easily
detached for cleaning.
In other cases, air chambers may be connected to passages containing wire
gauze, shot or other suitable material, so arranged that air can permeate through,
but flame cannot pass.

page_text: Where no connection to the external air is desirable, air passages-1, P Fig. 7‚—
may be connected to an enclosed cooling chamber through which the air circulates.
Although I have shewn 4-pole continuous-current motors in the drawings, my
invention is applicable to any form of enclosed motor, whether bi-polar or multi-
polar, whether for continuous, or alternating current. The fan may be placed
at either end of the armature.
Thus by means of this invention, the efficient ventilation of electric motors can
be maintained, whether the motors be working in mines, mills, on tram-cars, or
under any other conditions.
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
(1) Generally the formation of a suction and delivery chamber (or their equiva-
lent) in an enclosed electric motor, whether bi-polar, or multipolar, in connection
with a fan on the armature so as to secure mechanical ventilation, or circulation,
in any direction desired, substantially as herein described.
(2) The particular arrangement for discharging air into an enclosed electric
motor, substantially as shewn in Figs. 1 & 2.
(3) The particular arrangement for sucking air out of an enclosed electric
motor and directing the inflow to special places substantially as shewn in Figs. I
& 3.
(4) The means of circulating the air within an enclosed electric motor, and
directing the current to special places substantially as shewn in Fig. 4.
(5) The means of circulating air through the motor which may be drawn from
some other place than that in which the motor is situated by means of pipes in
connection with the fan and motor chambers herein described, as indicated on
Fig. 7.
(6) The means of circulating the air through an independent cooling arrange-
ment as indicated by Fig. 7, which is not open to the atmosphere, by means of
pipes in connection with the fan and motor chambers herein described.
Dated this 23rd day of February 1899.
WILSON HARTNELL.