摘要 |
<p>A shear fluid, temperature responsive fan drive coupling for the radiator cooling fan of an internal combustion engine. The drive coupling, conventionally, carries a temperature responsive valve which controls the degree of rotary coupling between the engine and the radiator cooling fan by controlling the quantity of shear fluid between a driving disc and a driven housing carrying the fan. The disc and the housing are parts of the coupling. The specific improvement of this invention relates to the provision of accumulator grooves in -the walls of the drive chamber. These grooves allow an increase in the volume of shear (torque-transmitting) liquid in the coupling. The coupling exhibits modulated torque transmitting action in passing from partial to full engagement as temperature is varied.</p> |