Yamada Yuki Seizo Co., Ltd.

Yamada T.s. Co. Ltd.

Yamada Corporation

501 Yamada Yuki Seizo Co., Ltd.

Kazumasa Yamada

Minoru Murata

A restarting device of a pump including a center rod defining fluid delivering chambers and driving chambers and . The restarting device of the pump further includes: a change-over valve for switching a direction for the center rod to move, and a restarting hydraulic circuit which, when a supply of the driving fluid from the change-over valve to the driving chambers and in both sides is stopped, detects the supply of the driving fluid into the driving chambers and in both sides having been stopped and then causes the driving fluid to flow into the change-over valve, thereby restarting the supply of the driving fluid into the driving chambers and

Restarting device for a fluid operated double diaphragm piston pump

A diaphragm pump is provided with a diaphragm defining a pump chamber and a drive chamber in the pump housing, a driving fluid is supplied to the drive chamber and a pump fluid is expelled from the pump chamber. The diaphragm pump is provided with pressure control means which, when the pressure in the pump chamber surpasses the pressure in the drive chamber neighboring the pump chamber across the diaphragm, controls the pressure of the driving fluid based upon output signals from pressure sensors in such a manner that the pressure in the fluid chamber will become higher than the pressure in the neighboring drive chamber. This makes it possible to prevent a diaphragm reversal phenomenon, wherein a diaphragm that should expand toward the pump chamber contracts toward the drive chamber instead during reciprocation of the diaphragm.

Diaphragm pump

A diaphragm assembly has a center disk in which use of a metal member is not required. The center disk comprises first and second center disk members, made of resin, embracing a resin diaphragm between them. The first center disk member has an inwardly directed inner flange on an inner peripheral wall defining a resin charging space, and the second center disk member comprises a resin-molded body, formed by charging a resin, and has an outwardly directed outer flange. A portion of the diaphragm is clamped between the inner flange and the outer flange.

Diaphragm assembly and method of manufacturing same

The objective of the present invention is to provide a reciprocation switching device for a pump which will solve problems of conventional devices such as that, because coil springs are used for activating by their snap action valve operators or switching operators serving to control the pressure of pump working fluid in relation to reciprocating action of the pump, such devices require the numerous number of parts including spring fitting shafts, the structure to attach such fitting shafts, parts for spring holders, etc.; and that the assembling of those parts is troublesome. A device according to the present invention uses one or two wire springs made into a C-like shape as the springs for the aforementioned purpose and calls for fitting said springs directly between the spring fitting section(s) and the valve operator or the switching operator.

Switching device for reciprocating pumps

The objective of the present invention is to provide a reciprocation switching device for a pump which will solve problems of conventional devices such as that, because coil springs are used for activating by their snap action valve operators or switching operators serving to control the pressure of pump working fluid in relation to reciprocating action of the pump, such devices require the numerous number of parts including spring fitting shafts, the structure to attach such fitting shafts, parts for spring holders, etc.; and that the assembling of those parts is troublesome. A device according to the present invention uses one or two springs made into a C-like shape as the springs for the aforementioned purpose and calls for fitting said springs directly between the spring fitting section(s) and the valve operator or the switching operator.

Spool type switching valve device

A pressure chamber of a diaphragm pump having an outer chamber improved so that it is free from stress concentration. The inner wall surface of the pressure chamber is recessed in a mero-spherical shape. In order to support this chamber wall from its rear side, an outer ring rib is provided along the outermost periphery of the outer surface of the chamber, and an inner ring rib is circumferentially disposed at the inner side of the outer ring rib. Further, radial ribs are provided so as to connect together the outer and inner ring ribs in the radial direction.

Growing community of inventors

Tokyo, Japan

Kazumasa Yamada