External control type fan-coupling device

Abstract

To reduce the size/weight and the power consumption of a fan-coupling device and to provide an external control type fan-coupling device intended to improve a fan rotation controllability. A fan-coupling device, in which the inside of a sealed housing borne on a rotary shaft fixing a drive disk thereon is divided by a partition into an oil sump and a torque transmission chamber housing the drive disc, so that the drive torque may be transmitted to a driven side with the oil fed into the torque transmission chamber and so that the communication passage of oil may be opened/closed and controlled by a valve member to be activated by an electromagnet. In the fan-coupling device, a magnetic member of either an integral structure or a split structure composed of a plurality of parts and assembled integrally is arranged between the electromagnet and the valve member (or armature), and the magnetic member is so assembled in the sealed housing that the magnetic flux of the electromagnet may be transmitted through the magnetic member to the armature.