System for controlling cooling water temperature for water-cooled engine

Abstract

A system for controlling cooling water temperature for an engine has a radiator, a cooling water passage communicating a water jacket in the engine with the radiator, and a thermostat provided in the cooling water passage. The system is provided with a bypass for bypassing the thermostat, a bypass valve provided in the bypass for closing the bypass; and a solenoid operated valve for actuating the bypass valve. Switch circuits are connected parallel to the solenoid operated valve means. The switch circuits comprises a low temperature switch responsive to low cooling water temperature to effect the operation of the solenoid operated valve for closing the bypass valve of the bypass, a high temperature switch responsive to high cooling water temperature to effect the operation of the solenoid operated valve for closing the bypass valve, a light load switch responsive to the light load operation of the engine to effect the operation of said solenoid operation valve for closing the bypass valve, and a heater switch connected to the high temperature switch in series, whereby the cooling water temperature is controlled according to the engine operation and the heater operation.

Dependencies are inferred from the claim text.