Patent ID: 7540170

Claim:
A liquid pressure-feed device comprising; a closed vessel, the closed vessel having a working fluid inlet port, a working fluid discharge port, a liquid inlet port and a liquid discharge port; a float, a change-over valve and a snap mechanism provided within the closed vessel; wherein the snap mechanism comprises; a pivot shaft supported within the closed vessel, a float arm and a sub-arm both adapted to rotate about the pivot shaft, a first shaft supported by the float arm, a second shaft supported by the sub-arm, and; a spring mounted between the first and second shafts; wherein the float is connected to the float arm; wherein the change-over valve is connected to the sub-arm through a power transfer shaft; and wherein a stopper shaft is supported within the closed vessel, there being formed in the float arm a first window through which the stopper shaft extends such that the stopper shaft and the first window cooperate to restrict a rotational range of the float arm with floating of the float, and there being formed in the sub-arm a second window through which the stopper shaft extends such that the stopper shaft and the second window cooperate to restrict a rotational range of the sub-arm with descent of the float.