A valve for hydraulic control of fluid flow rate, comprising: a body provided with an inlet opening, an outlet opening and an actuating opening; a rotating hollow shutter rotatively housed inside said body, said rotating shutter being configured to be crossed by a fluid and to change the passage cross-section inside the valve, in which the rotating shutter comprises at least one first opening rotatively cooperating with at least one mated second eccentric opening, said rotating shutter being configured to be manually actuatable inside the body so that a rotation of said first opening with respect to said second opening is matched by a variation of the fluid passage cross-section in a direction substantially coinciding with the rotation axis.

A medical device includes a constant-flow pump configured to pump a fluid through a fluid conduit and a rotary valve fluidically connected to the pump. The rotary valve includes at least one rotatable valve member configured to be operatively connected to and rotate relative to the fluid conduit. The rotatable valve member includes at least one aperture. The rotatable valve member is capable of being positioned in a plurality of positions relative to the conduit. The position of the at least one first aperture of the rotatable valve member controls fluid flow through the rotary valve, and thereby through the conduit.

A disc for a multiple orifice valve includes a disc body and a disc orifice extending through the disc body. A disc surface of the disc body includes a recessed portion and a raised portion that at least partially circumferentially surrounds the recessed portion. The recessed portion is configured not to contact an opposed disc when the disc is assembled within a housing of the multiple orifice valve, and the raised portion is configured to contact the opposed disc when the disc is assembled within the housing of the multiple orifice valve.

An eclipse valve includes at least two obturator plates captured in a sealed housing that are driven to move in opposite directions relative to each other within the sealed housing. The obturator plates fill the width of a cavity within the housing and can be moved between aligned and unaligned positions. Each of the obturator plates have an opening through the plate, and when the obturator plates are aligned, the openings through the plates are aligned with each other, and with front and rear openings in the housing, allowing flow through the valve. The plates can be moved to reduce the overlap of the openings through the plates within the housing in an eclipse manner to adjust the rate or amount of flow, and to shut off flow by completely un-aligning the openings.

Variable flow characteristic valves are disclosed. A disclosed example valve for controlling a flow characteristic therethrough includes a first plate having a first aperture pattern, a second plate proximate the first plate, the second plate having a second aperture pattern, and a rotator to rotate the second plate relative to the first plate to vary a degree of alignment between the first and second aperture patterns.

A fallback prevention valve apparatus, system and method is described. An electric submersible pump (ESP) fallback prevention system includes an ESP assembly positioned in a downhole well, the ESP assembly including production tubing extending between a centrifugal pump and a surface of the downhole well such that during operation of the ESP assembly production fluid flows upward from the centrifugal pump through the production tubing to the surface, the production tubing including a fallback valve actuatable by the flow of production fluid, the fallback valve actuatable between an open position, wherein production fluid flowing upward through the fallback valve actuates the fallback valve into the open position, and a closed position, wherein production fluid flowing downward through the fallback valve actuates the fallback valve into the closed position, the closed position blocking sand carried by the production fluid from falling into the centrifugal pump.

A pressure gauge system for a tank with a variable flow rate that provides a user with an indication of how much usable time is left in a pressurized gas tank given a particular selected flow rate or operational condition and what pressure of gas is left in the tank.

An eclipse valve includes at least two reciprocating obturator plates captured in a sealed housing. The obturator plates fill the width of a cavity within the housing and can be moved between aligned and unaligned positions. Each of the obturator plates have an opening through the plate, and when the obturator plates are aligned, the openings through the plates are aligned with each other, and with front and rear openings in the housing, allowing flow through the valve. The plates can be moved to reduce the overlap of the openings through the plates within the housing in an eclipse manner to adjust the rate or amount of flow, and to shut off flow by completely un-aligning the openings.

A valve in which the flow control element includes a fixed disk and a rotatable disk, and a motor operable to rotate the rotatable disk. The motor is disposed in the bore of the valve, aligned with the long axis of the valve body and the axis of rotation of the rotatable disk.

Flow modulator (10) for a fluid like combustion gas, comprising: a housing (11), a modulator body (14) positioned with the housing (11), and a valve body (18) positioned with the housing (11). The modulator body (14) has a flow channel (15) and an opening (16) providing together a flow passage (17) for the fluid. The valve body (18) is provided by a foil element (19), wherein the foil element (19) has an opening (20) for the fluid, wherein the foil element (19) is rotatable relative to the modulator body (14) to modulate the flow of the fluid by adjusting an overlap between the opening (20) of the valve body (18) and the flow passage (17) of the modulator body (14), and wherein the foil element (19) is positioned up-stream of the modulator body (14) such that an inlet pressure of the fluid presses the foil element (19) against the modulator body (14) thereby providing a sealing level between the foil element (19) and the modulator body (14).