Membrane pump device, wherein the membrane pump device comprises a housing, and the housing contains a first and a second chamber, wherein the first chamber is separated from the second chamber by a movable membrane, while a liquid being pumped can be introduced in the first chamber, and a drive liquid can be introduced into the second chamber, wherein the second chamber has an outlet opening, and the outlet opening is present on an outer side of the housing. The membrane pump device is characterized in that the membrane pump device comprises a valve, while the valve is arranged at the outlet opening and closes off the second chamber from the outside.

A water pump assembly includes a lower housing configured for being positioned within a well. The lower housing includes a bladder therein. The bladder expands to force water within the housing into an outlet of a valve apparatus and the bladder contracts to draw water into the housing. A cylinder and piston fluidly coupled to an inlet of the valve apparatus and the inlet is fluidly coupled to the bladder. A one way valve is positioned within the valve apparatus and fluidly connects an inlet chamber including the inlet to an outlet chamber including the outlet. The one way valve allows water to flow from the outlet chamber into the inlet chamber and restricts water from flowing from the inlet chamber into the outlet chamber. An outlet conduit is fluidly coupled to the outlet of the valve apparatus to carry the water where desired.

A water pump assembly includes a lower housing configured for being positioned within a well. The lower housing includes a bladder therein. The bladder expands to force water within the housing into an outlet of a valve apparatus and the bladder contracts to draw water into the housing. A cylinder and piston fluidly coupled to an inlet of the valve apparatus and the inlet is fluidly coupled to the bladder. A one way valve is positioned within the valve apparatus and fluidly connects an inlet chamber including the inlet to an outlet chamber including the outlet. The one way valve allows water to flow from the outlet chamber into the inlet chamber and restricts water from flowing from the inlet chamber into the outlet chamber. An outlet conduit is fluidly coupled to the outlet of the valve apparatus to carry the water where desired.

A fluid filtration assembly includes a filter housing having a first end for fluid connection with a fluid storage vessel. A filter cartridge is disposable within the filter housing, and a plunger pump is coupled at a second end of the filter housing. The plunger pump includes a housing having a rigid portion and a flexible portion. The flexible portion has a plunger-engaging portion for coupling to the plunger of an actuator. The flexible portion selectively movable with respect to the rigid portion via the actuator. The filter cartridge can be a hollow fiber filter. The plunger pump can be configured to induce alternating tangential flow in at least a portion of the assembly. The fluid filtration assembly can be provided as a disposable single-use arrangement.

A fluid filtration assembly includes a filter housing having a first end for fluid connection with a fluid storage vessel. A filter cartridge is disposable within the filter housing, and a plunger pump is coupled at a second end of the filter housing. The plunger pump includes a housing having a rigid portion and a flexible portion. The flexible portion has a plunger-engaging portion for coupling to the plunger of an actuator. The flexible portion selectively movable with respect to the rigid portion via the actuator. The filter cartridge can be a hollow fiber filter. The plunger pump can be configured to induce alternating tangential flow in at least a portion of the assembly. The fluid filtration assembly can be provided as a disposable single-use arrangement.

A hydraulic pumping system in accordance with embodiments comprises a breast interface operably coupled to an actuatable assembly by means of an actuatable assembly interface. The breast interface comprises a distal membrane coupled to a housing to form a fluid reservoir therebetween. The actuatable assembly interface comprises a proximal membrane. The distal and proximal membranes are fluidly coupled via a tube carrying a driving fluid. The actuatable assembly interface is configured to removably couple to the actuatable assembly, in order to operably couple the actuatable assembly to the breast interface. The actuatable assembly interface comprises a fluid shut off mechanism to reversibly shut off fluid communication between the breast interface and the actuatable assembly interface when the actuatable assembly interface is decoupled from the actuatable assembly.

The present invention relates to a method of determining a system compressibility value of a medical membrane pump drive, wherein a first and second pressure level are moved to and a first and second operating parameter value of the membrane pump drive are detected; wherein the system compressibility value is determined on the basis of the detected operating parameter values; and wherein the membrane of the membrane pump drive is supported at a rigid surface during the determination of the system compressibility value.

The present invention relates to a method of determining a system compressibility value of a medical membrane pump drive, wherein a first and second pressure level are moved to and a first and second operating parameter value of the membrane pump drive are detected; wherein the system compressibility value is determined on the basis of the detected operating parameter values; and wherein the membrane of the membrane pump drive is supported at a rigid surface during the determination of the system compressibility value.

The present disclosure provides an oil scavenge pump, which includes a cap member, a piston member and a resilient member. The cap member and the piston member are connected to each other and with the resilient member therebetween. The cap member includes a cap head, a valve connected to the cap head, a resilient unit disposed between the cap head and the valve, and a first sphere disposed between the resilient unit and the valve. The piston member includes a valve stopper, a main portion, a second sphere, a rod portion, a first-seal ring and a second-seal ring. The main portion has two ends respectively connected to the valve stopper and the rod portion. The second sphere is disposed between the valve stopper and the main portion. The first-seal ring and the second-seal ring respectively surround the main portion and the rod portion.

The present disclosure provides an oil scavenge pump, which includes a cap member, a piston member and a resilient member. The cap member and the piston member are connected to each other and with the resilient member therebetween. The cap member includes a cap head, a valve connected to the cap head, a resilient unit disposed between the cap head and the valve, and a first sphere disposed between the resilient unit and the valve. The piston member includes a valve stopper, a main portion, a second sphere, a rod portion, a first-seal ring and a second-seal ring. The main portion has two ends respectively connected to the valve stopper and the rod portion. The second sphere is disposed between the valve stopper and the main portion. The first-seal ring and the second-seal ring respectively surround the main portion and the rod portion.