A convertible check valve having a pair of valve body sections, each of which includes a central passageway extending through it is disclosed. Each passageway terminates at an elliptical port. A moveable flapper is located within the check valve between the valve body sections and is movable between a between a closed state and an opened state, and vice versa, to effect the selective closing and opening of the ports. The valve body sections are configured to be rotated 180 degrees with respect to each other so that they are in an either an axially aligned state or in an elbow state. The interface between the passageways is formed by two elliptical shaped planar surfaces, each extending at an angle of 45 degrees to the central axis of the associated passageway. The valve also includes a pressure relief assembly.

A convertible check valve having a pair of valve body sections, each of which includes a central passageway extending through it is disclosed. Each passageway terminates at an elliptical port. A moveable flapper is located within the check valve between the valve body sections and is movable between a between a closed state and an opened state, and vice versa, to effect the selective closing and opening of the ports. The valve body sections are configured to be rotated 180 degrees with respect to each other so that they are in an either an axially aligned state or in an elbow state. The interface between the passageways is formed by two elliptical shaped planar surfaces, each extending at an angle of 45 degrees to the central axis of the associated passageway. The valve also includes a pressure relief assembly.

An assembly for actuating a double-acting shift cylinder of a shift assembly of an automatic transmission of a motor vehicle includes a hydraulic fluid reservoir having a motor-driven hydraulic pump and two control valves that are each connected to a pressure supply line of the hydraulic pump and to a return line to the hydraulic fluid reservoir. The shift cylinder has two pressure chambers that are each connected to one of the control valves. The control valves each connect one pressure chamber of the shift cylinder to the pressure supply line of the hydraulic pump or to the return line to the hydraulic fluid reservoir. The actuating assembly includes at least one pressure-limiting valve that connects the pressure supply line to the return line if a hydraulic over-pressure is present. The control valves can be 3/2-directional valves having integrated pressure-limiting valves.

An assembly for actuating a double-acting shift cylinder of a shift assembly of an automatic transmission of a motor vehicle includes a hydraulic fluid reservoir having a motor-driven hydraulic pump and two control valves that are each connected to a pressure supply line of the hydraulic pump and to a return line to the hydraulic fluid reservoir. The shift cylinder has two pressure chambers that are each connected to one of the control valves. The control valves each connect one pressure chamber of the shift cylinder to the pressure supply line of the hydraulic pump or to the return line to the hydraulic fluid reservoir. The actuating assembly includes at least one pressure-limiting valve that connects the pressure supply line to the return line if a hydraulic over-pressure is present. The control valves can be 3/2-directional valves having integrated pressure-limiting valves.

A shoe in form of a slipper or sandal, includes a body 100 adapted to have a first fluid casing 12 and a second fluid casing 14, each having an elastic property, embedded in the front and rear portions of the body, respectively, and an instep strap 120 supported to the body in such a way as to be rotated in a specific section. A rotating shaft 16 is rotated in conjunction with the instep strap, and it includes a first connecting portion connected to the first fluid casing and a second connecting portion connected to the second fluid casing and an internal passage having respective check ball seating portions formed on the inside of the first and the second connecting portions, and with check ball received in the internal passage. When the rotating shaft is inclined by rotation of the rotating shaft, the check ball closely adheres to any one of the check ball seating portions by gravity or buoyancy and regulates a fluid flow to any one of the first and the second connecting portions.

A valve assembly includes a linearly moving main slider, a pilot valve, a control oil inlet, and a control oil return. The pilot valve is designed as a 4/3 proportional directional valve, via which a first end face and an opposite second end face of the main slider can be fluidly connected selectively to the control oil inlet or the control oil return so that the main slider (20) is hydraulically movable by adjusting the pilot valve. The pilot valve is electrically adjustable depending on a target current. A position sensor is provided, with which an actual position of the main slider can be measured. A positioner is provided, with which the actual position can be regulated by adjusting the target current to a predefinable target position. The pilot valve is connected to the control oil return via a check valve. The check valve only permits fluid flow from the pilot valve toward the control oil return. The check valve is preloaded to a closed position by means of a first spring so that it opens at a predetermined opening pressure. The leakages at the pilot valve from the control oil inlet toward the check valve are designed to be so large that if the pressure at the control oil inlet exceeds the opening pressure by at least 2 bar, the opening pressure of the check valve is present immediately upstream of the check valve.

An arrangement for managing a liquid medium, such as water, combines a pressure-reducing valve with two backflow prevention valves. Both the pressure-reducing valve and the two backflow prevention valves may be integrated into a common housing, specifically with both backflow prevention valves in an inlet chamber of the housing, wherein the inlet chamber and an outlet chamber of the housing are either fluidly coupled or isolated from one another by the pressure-reducing valve depending on the outlet chamber pressure prevailing in the outlet chamber. In some instances, a manually actuatable shut-off valve may be integrated into the housing. The manually actuatable shut-off valve may selectively keep the pressure-reducing valve in a closed position or allow the automatic opening and closing of the pressure-reducing valve depending on the outlet chamber pressure prevailing in the outlet chamber.

A major challenge for the general use of “lab-on-a-chip” (LOAC) systems and point-of-care (POC) devices has been the generally complex and need for sophisticated peripheral equipment, such that it is more difficult than anticipated to implement low cost, robust and portable LOAC/POC solutions. It would be beneficial for chemical, medical, healthcare, and environmental applications to provide designs for inexpensive LOAC/POC solutions compatible with miniaturization and mass production, and are potentially portable, using compact possibly hand-held instruments, using reusable or disposable detectors. Embodiments of the invention address improved circuit elements for self-powered self-regulating microfluidic circuits including programmable retention valves, programmable trigger valves, enhanced capillary pumps, and flow resonators. Additionally embodiments of the invention allow for the flow direction within a microfluidic circuit to be reversed as well as for retention of reagents prior to sale or deployment of the microfluidic circuit for eased user use.

A major challenge for the general use of “lab-on-a-chip” (LOAC) systems and point-of-care (POC) devices has been the generally complex and need for sophisticated peripheral equipment, such that it is more difficult than anticipated to implement low cost, robust and portable LOAC/POC solutions. It would be beneficial for chemical, medical, healthcare, and environmental applications to provide designs for inexpensive LOAC/POC solutions compatible with miniaturization and mass production, and are potentially portable, using compact possibly hand-held instruments, using reusable or disposable detectors. Embodiments of the invention address improved circuit elements for self-powered self-regulating microfluidic circuits including programmable retention valves, programmable trigger valves, enhanced capillary pumps, and flow resonators. Additionally embodiments of the invention allow for the flow direction within a microfluidic circuit to be reversed as well as for retention of reagents prior to sale or deployment of the microfluidic circuit for eased user use.

Flow control valves may be positioned downstream of water meters to increase pressure and compress entrained water vapour passing through the meters. However, turbulence within such valves can cause the valve's head to move radially, bending a shaft within the valve which may break. Accordingly, there is provided a flow control valve comprising: a housing having a flow passage; a valve seat defined within the flow passage; a valve head moveable to a closed position to engage the valve seat and seal the flow passage; a shaft secured to the valve head; a support slidingly mounting the shaft within the housing; a spring biasing the valve head to the closed position and configured to maintain the valve head in the closed position until a predetermined pressure is applied; and a guide assembly extending along at least a portion of the flow passage to constrain radial movement of the valve head.