Device for controlling the means (1) for recirculating a cooling fluid in
engines (11a) in particular for vehicles and like, comprising a shaft (2)
actuating the impeller, means (3,3b) for generating the movement of said
shaft and means for transmitting the movement from the said generating
means (3,3b) to the said shaft (2) of the impeller (1), in which said
movement transmission means comprise a double-action coupling (30,40)
comprising: magnetic means (31) integral with a rotor (30;130;230) and
able to cooperate with corresponding magnetizable means (41;141;241) of a
support (40;140;240) rotationally connected to the shaft (2) of the
recirculating means and movable in an axial direction with respect
thereto, so as to determine a first speed of rotation of the
recirculating means (1), and electromagnetic means (22,22a) able to
co-operate with a ring (41a;141a;241a) integral with said support
(40;140;240) so as to determine a second and different speed of rotation
of the pump impeller (1).