节温器的作用是用来自动调节冷却水的循环。当发动机的冷却水温度低于正常工作温度时,它的主阀门关闭,旁通间打开,冷却水直接从旁通阀流回水泵不经散热器而进行小循环,使发动机温度迅速升高。当水温超过70℃时,主阀门逐渐打开,旁通阀逐渐关小,部分冷却水 Thermostat is used to automatically adjust the cooling water circulation. When the engine cooling water temperature is lower than the normal operating temperature, its main valve is closed, the bypass between the open, cooling water directly from the bypass valve back to the pump without the radiator and a small cycle, the engine temperature rose rapidly. When the water temperature exceeds 70 ℃, the main valve gradually opened, the bypass valve is gradually closed, part of the cooling water