摘要 |
<p>ENGINE TEMPERATURE CONTROL SYSTEM The operating temperature of an internal combustion engine is maintained within desired limits by employing a single coolant temperature sensor (10) for controlling and coordinating the operation of three different temperature control devices (45,46,47) for the engine coolant. When the sensed coolant temperature is in a relatively low range a flow control valve (45) controls the amount of coolant diverted from the engine jacket to a radiator (48) to dissipate heat absorbed by the coolant from the engine. If the coolant temperature exceeds that low range, even though the control valve (45) is fully open and all of the coolant is circulated through the radiator (48), the sensor (10) then effects the opening of radiator shutters (46) to cause ram air to impinge on the radiator (48) to increase the cooling of the coolant. If the temperature still continues to rise after the shutters (46) are fully open, the coolant sensor (10) causes operation of a variable speed fan drive (47) to blow a sufficient amount of air through the radiator (48) to cool the coolant back down to the desired operating range. Such sequential operation of the three control devices (45,46,47) provides close temperature control within a relatively narrow range despite wide variations of external conditions and load on the engine, resulting in higher efficiency and longer engine life.</p> |