air in device here more energy can be stored in the pressure water vessel 1 u2032 and the flush performance can be better as shown in fig1 the present invention includes a pressure water vessel 1 an infill valve 2 a combination valve 3 a flush valve 4 and an open valve 5 the infill valve 2 is fixed at the bottom of the pressure water vessel 1 the combination valve 3 is fixed on the top of the pressure water vessel 1 the flush valve 4 is fixed through the pressure water vessel 1 and the open valve 5 can be fixed at any position of the ceramic toilet tank 6 namely the front side or top of the toilet tank below is the detailed description of all these sub assemblies the pressure water vessel 1 is a sealed container made of high strength and high stability material an opening 11 is centered on the top of the pressure water vessel 1 the outlet 12 is set under the opening 11 and some external threads are set in the peripheral lower section of the outlet 12 to connect with the inlet of the toilet tank a locating plate 13 is set at the top of the outlet 12 an outlet 14 is set under the locating plate 13 and inside the upper section of the outlet 12 and its inner.