System for controlling coolant temperature of internal combustion engine
AssigneeNissan Motor Co., Ltd.
InventorsShinichi Nagumo, Yoshio Toda, Yasuo Nakajima, Yoshifumi Hase
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Abstract
A system for controlling a coolant temperature of an internal combustion engine comprises means for detecting operating condition of an engine, means for setting a different target coolant temperature for the detected operating condition, a flow control valve disposed in a coolant recirculating passage, and means for effecting a feedback control of opening degree of said flow control valve in such a manner as to adjust the actual coolant temperature toward the target coolant temperature.
Claims7
A system for controlling temperature of coolant circulating through an engine main body of an internal combustion engine having a plurality of operating conditions, comprising:
- a coolant circulating circuit including a radiator, an outlet passage passing a relatively hot coolant from the engine main body to said radiator, an inlet passage passing a relatively cool coolant from said radiator to the engine main body and a bypass passage having one end connected to said outlet passage and an opposite end connected to said inlet passage for passing the relatively hot coolant directly to the relatively cool coolant bypassing said radiator;
- a temperature sensor means, disposed in said coolant circulating circuit, for sensing an actual coolant temperature of the coolant in said coolant circulating circuit and generating an actual coolant temperature indicative signal indicative of the sensed actual coolant temperature;
- means for storing coolant temperature values corresponding, respectively, to said plurality of operating conditions of the engine;
- means for detecting a present operating condition of the internal combustion engine and generating an operating condition indicative signal indicative of the detected operating condition;
- means for retrieving the coolant temperature value corresponding to the detected operating condition of the engine indicated by said operating condition indicative signal and generating a target coolant temperature indicative signal indicative of said retrieved coolant temperature value;
- means for comparing said actual coolant temperature indicative signal with said target coolant temperature indicative signal and generating a result indicative signal indicative of the result of said comparison;
- and
- means responsive to said result indicative signal for controlling the flow rate of coolant passing through said radiator in such a manner as to decrease a difference between said actual coolant temperature indicative signal and said target coolant temperature indicative signal.
Dependencies are inferred from the claim text.