Improvements in or relating to electrically driven fans

Abstract

Abstract 594,165. Ventilators. AKTIEBOLAGET ELEKTROLUX. May 29, 1945, No. 13406. Convention date, July 12, 1944. [Class 137] [Also in Group XXVI] In a ventilating unit for mounting over a wall duct comprising an electrically driven fan and an adjustable damper operated together with the motor control, the fan is carried in a box - like casing 10 comprising front and rear walls provided with openings, the rear wall being mounted on the building wall so as to lie adjacent thereto with the casing outside the duct. The fan wheel 14 is contained in a chamber 12 and the motor 13 projects through the rear casing wall. The damper 11 co-operates with the front opening and its regulating mechanism together with a motor control member are enclosed in a dust-proof manner within the casing and are actuated simultaneously by remote control means such as a cord 29. In the form shown, the fan motor is controlled by a one-way rotary switch (not shown) having two open positions, one position for half-speed and one for full-speed, and a cam disc 35 rotates therewith to actuate a lever 27 to open and close the damper which is pivotally supported at 24 by a lazy-tongs device 125, 128. In a modification, the motor control member comprises a sliding plate reciprocated by two draw cords and having a conducting tongue co-operating with laminated contact springs, and a curved groove is provided to receive the lever 27. The damper may be maintained at an angle to the plane of the wall when open by means of a torsion spring and/or an adjustable chain. As shown, a torsion spring 50 causes the damper 11 to bear resiliently against the arms 128 of the lazy-tongs. These arms are not shown in other forms of the damper supports. A coloured indicating device may be provided to show the position of the motor control member.

Inventors

No inventors recorded.

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