Accumulator

PURPOSE:To prevent the excessive deformation of a flexible diaphragm and always adsorb pressure fluctuation well, by causing the pressure accumulation chamber of an accumulator body to receive the fluid pressure of a pipe by two parts which are the flexible diaphragm and a movable partition wall. CONSTITUTION:A working oil flows from a plug 19 to another 18 through an annular passage between an oil pressure pipe 2 and an outer pipe 4. When pulsating flow takes place in the pipe 2 in that state, the pulsating flow thrusts a flexible diaphragm 7 through a hole 5 against a coiled spring 8. Pulsation is absorbed by the volume change of an opening 13 due to the deformation of the diaphragm 7. When the pressure conditions in the pipe 2 change and the working oil flows with high pressure through the pipe 2, a piston 9 is displaced along the an inner pipe 6 by the working oil introduced into the pipe 6 through perforated holes 18a, 11a to compress a gas sealed up in openings 14, 13. This results in preventing the flexible diaphragm 7 from being excessively deformed.