Centrifugal fan control

In a vehicle of the type including an engine having a crankshaft mounted therein for rotation about an axis and a fan having an input shaft defining an axis about which the fan rotates, the improvement comprising:

• means mounting the engine and fan with the axes transversely spaced apart and substantially parallel to each other and allowing the spaced apart distance between the axes to vary in response to variations in engine load;
• drive means connecting the input shaft with the crankshaft, said drive means including a drive belt and tensioning means for maintaining a relatively constant tension on said belt as said spaced apart distance varies;
• means for sensing the cooling requirements of the engine;
• and
• means drivingly interposed between the crankshaft and the fan for varying the rotational speed of the fan with respect to the rotational speed of the crankshaft in response to the sensed cooling requirements of the engine.

In a vehicle of the type including an engine having a crankshaft mounted therein for rotation about an axis and a fan having an input shaft defining an axis about which the fan rotates, the improvement comprising:

• means mounting the engine and fan such that the axes are disposed transverse to the longitudinal axis of the vehicle, substantially parallel to each other, and spaced apart with respect to the longitudinal axis, said mounting means allowing the spaced apart distance between the crankshaft and fan axes to vary in response to engine load;
• said fan being a cross-flow fan;
• drive means connecting the input shaft with the crankshaft, said drive means including a drive belt and tensioning means for maintaining a relatively constant tension on said belt as said spaced apart distance varies;
• and
• means drivingly interposed between the crankshaft and the fan for varying the rotational speed of the fan with respect to the rotational speed of the crankshaft in response to the cooling requirements of the engine.

In a vehicle of the type including a frame, an engine having a crankshaft mounted therein for rotation about an axis, means mounting the engine on the frame such that the crankshaft rocks transverse to the crankshaft axis in response to varying engine load, and an engine cooling fan having an input shaft defining an axis about which the fan rotates, the improvement comprising:

• means mounting the fan with the fan axis laterally spaced from and substantially parallel to the crankshaft axis and fixed against movement relative to the frame, whereby the spaced apart distance between the fan and crankshaft axes varies in response to varying engine load;
• drive means connecting the input shaft with the crankshaft, said drive means including a drive belt and tensioning means for maintaining a relatively constant tension on said belt as said spaced apart distance varies;
• and
• a viscous coupling drivingly interposed between the crankshaft and the fan for varying the rotational speed of the fan with respect to the rotational speed of the crankshaft in response to the cooling requirements of the engine.