| 摘要 |
PURPOSE:To prevent knocking by introducing a Venturi and a suction negative pressure into both negative pressure chambers of a diaphragm device to change the reference point of a cooling-liquid control thermostat for setting a set temperature in a low-speed and high-load area at a low temperature control area. CONSTITUTION:A thermostat 2 is provided on the way to a cooling-liquid 1 of an internal-combustion engine, and its shaft 8 is in contact with a rod 9 connected with a diaphragm 21 of a diaphragm unit 20. A negative pressure chamber 23 in which a suction negative pressure P1 of a suction pipe 26 in the downstream of a throttle valve 15 is introduced, is provided on the upper part of the diaphragm 21, while on the lower part, a Venturi negative pressure chamber 22 in which a Venturi pressure Pv of a Venturi part 17 is introduced, is furnished. At the time of low speed and high load of an engine when the suction negative pressure P1 is small and the Venturi negative pressure Pv is large, the diaphragm 21 is moved downward to lower the set temperature of the thermostat 2. |
