PURPOSE: To make large of deformability of a diaphragm and miniaturize the same while making it possible to laminate a plural number of sheets by using characteristics of a cone for making continuous operation possible even when a small number of sheets are broken by making the diaphragm conical.

CONSTITUTION: A hydraulic plunger 1 and a cam shaft 2 are respectively housed inside a pump body 6, while among those, are respectively equipped with a connecting metal 3, a cylindrical pin 4 and terminal stud 5. Again, a conical diaphragm 8 laminated a conical base material in plural numbers of sheets is housed and equipped via a diaphragm cassette 9 inside the pump body 6. Moreover, conical mesh 9' is formed on a part of the diaphragm cassette 9 for deciding the bottom dead center of the conical diaphragm 8 while preventing overdeformation. The conical diaphragm 8 is made to deform with hydraulic pressure generated by the hydraulic plunger 1, and therewith is pressed water situated on opposite side to the diaphragm to deliver the same from a delivery valve 15.