Abstract: A flow sub for use with a drill string includes: a tubular housing having a longitudinal bore formed therethrough and a flow port formed through a wall thereof; a bore valve operable between an open position and a closed position, wherein the bore valve allows free passage through the bore in the open position and isolates an upper portion of the bore from a lower portion of the bore in the closed position; and a sleeve disposed in the housing and movable between an open position where the flow port is exposed to the bore and a closed position where a wall of the sleeve is disposed between the flow port and the bore; and a bore valve actuator operably coupling the sleeve and the bore valve such that opening the sleeve closes the bore valve and closing the sleeve opens the bore valve.

Abstract: A production assembly includes a tree body, in which the tree body includes a main production bore formed about an axis and a wing bore extending through the tree body from the main production bore. The tree body may further include a wing valve in fluid communication with the wing bore to control the flow of fluid through the wing bore, in which at least a portion of the wing bore is angled from perpendicular with respect to the axis of the main production bore.

Abstract: A valve comprises a housing including a first chamber, a second chamber, and a neutral chamber. In addition, the valve comprises a stem disposed within the housing. Further, the valve comprises a first valve member at least partially disposed in the first chamber and connected to the stem and a second valve member at least partially disposed in the second chamber and connected to the stem. The first valve member has a closed position seated in a first annular valve seat and an open position spaced apart from the first valve seat. The second valve member has a closed position seated in a second annular valve seat and an open position spaced apart from the second valve seat. Moreover, the valve comprises a biasing member configured to bias the second valve member to the closed position and the first valve member to the open position.

Abstract: A method for drilling a wellbore includes drilling the wellbore by injecting drilling fluid into a top of a tubular string disposed in the wellbore at a first flow rate and rotating a drill bit. The tubular string includes: the drill bit disposed on a bottom thereof, tubular joints connected together, a longitudinal bore therethrough, a port through a wall thereof, and a sleeve operable between an open position where the port is exposed to the bore and a closed position where a wall of the sleeve is disposed between the port and the bore. The method further includes moving the sleeve to the open position; and injecting drilling fluid into the port at a second flow rate while adding a tubular joint(s) to the tubular string. The injection of drilling fluid into the tubular string is continuously maintained between drilling and adding the joint(s).

Abstract: A shuttle valve 8 includes a valve body 9, a shuttle 10, and an actuator mechanism 11. The shuttle valve 8 includes inlet ports 37 and 39 and outlet port 40. The shuttle 10 moves between first and second at rest positions to selectively connect one of the inlet ports to the outlet port and isolate the other inlet port from the outlet port. The actuator mechanism 11 includes first and second springs 63 and 66 and moves the shuttle 10 from one of its positions to another when a set pressure differential is attained between the inlet ports. The actuator mechanism 11 moves a partial stroke distance to move the shuttle 10 between its at rest positions and moves a full stroke distance to additionally open fluid communication between one of the inlet ports and the shuttle 10.

Abstract: A hydraulic system (1) for actuating at least one shifting element (2) of a transmission. The hydraulic system comprises a regulating valve device (3) that can be preset and has a regulating valve slide (8), and a shifting valve device (4) which can also be preset and has a shifting valve slide (6). The shifting valve device (4) interacts with the regulating valve device (3). The regulating valve slide (8) and the shifting valve slide (6) are coaxially aligned with one another and move in opposite longitudinal directions within a common boring (24) of a housing (25). Each of the slides has a control surface (5, 14) which faces toward one another and can be pressurized with a pressure signal (p_VS) via a common pressure chamber (26).

Abstract: A water supply system that supplies water to a plumbing system from either a mains supply, or an auxiliary supply. In a default state, a shuttle valve is pressure balanced and couples water from the mains supply to the plumbing system via mains inlet port and outlet port, and in another state the shuttle valve is pressure unbalanced and moved so that auxiliary water is coupled to the plumbing system via an auxiliary inlet port and the outlet port of the shuttle valve. Water is drawn from an auxiliary tank and coupled to the plumbing system when two conditions exist, namely when water is demanded, as sensed by flow sensor, and when water is available from the auxiliary supply, as sensed by float system. Water pressure at the auxiliary inlet port causes the shuttle to move from the default state and couple water from the auxiliary inlet port to the outlet port and thus to the plumbing system.

Abstract: An air conditioning drain cleaning system with an automated blow-out cycle to clean out an evaporator pan drain pipe. The system has a pneumatic valve assembly, a controller, a float level switch assembly and a plurality of air lines in a manifold for actuating the pneumatic valve assembly and blowing out the drain pipe. The controller directs the system to initiate or repeat a blow-out cycle until the drain pipe is clear. The pneumatic valve assembly bisects the drain pipe to selectively close the pipe for cleaning with a pair of high pressure air shots, one shot toward each pipe end to dislodge a clog. The float level switch assembly signals the controller if the condensate level in the drain pan drops. If the condensate level does not drop, the controller initiates a further blow-out cycle at increased pressures until the line is clear.

Abstract: A check valve includes a valve body defining an internal chamber and a valve seat disposed within the internal chamber adjacent to one of the first and second ends of the valve body. A poppet is mounted for linear movement along a poppet axis within the internal chamber between the first and second ends of the valve body and has a predetermined cross-sectional shape in a direction transverse to the poppet axis, a peripheral rim defining a movement guiding surface, a frustoconical surface provided in one axial end of the poppet and oriented in a direction toward the one end of the valve body, a sealing bead disposed on the frustoconical surface, and a predetermined plurality of passages formed in a predetermined pattern through at least one of the peripheral rim and the frustoconical surface in open communication with an opposed axial end of the poppet.

Abstract: A gas turbine engine valve is disclosed. In one form the valve includes two inlets in fluid communication with an outlet. The valve can include a spool having two lands capable of selectively closing either of the two inlets. The valve can include energy storage devices that initially position the spool within a valve housing. A temperature motor is provided to position the spool based upon a temperature of a mixture of working fluid from the two inlets. A working fluid flowing into the first inlet can be in fluid communication with a second end of the valve; and a working fluid flowing into the second inlet can be in fluid communication with a first end of the valve. A relatively high pressure condition at one or the other of the inlets can be used to alter a position of the valve.

Abstract: Described are water-on-water valves for use in reverse osmosis filtration systems. The water-on-water valves are regulated by the pressure in a product line, which contains fluid from a product line of the filter module and/or the product side of a water-on-water storage tank. Exemplary valves are shuttle valves that are regulated by the pressure downstream of the product side of a reverse osmosis filter module. The valves may comprise a piston within a housing, and an end of the piston may have an enlarged diameter relative to the maximum diameter of the remainder of the piston.

Abstract: A regulated automatic changeover valve is provided. A device engages the first and second high pressure gas source for providing a lower pressure gas source downstream of the changeover valve. An eccentric is provided between two valve assemblies, with each valve assembly having a piston with a valve arm projecting therefrom. The eccentric moves a block selectively closer to one of the two valve assemblies. Each valve assembly is engaged to a high pressure source, such as a tank of compressed gas. When a first tank begins to run low, the valve will automatically begin drawing from the second valve assembly. A tank that has run low of compressed gas may be changed out while the second, non-exhausted gas continues to feed the downstream device at a regulated gas pressure.

Abstract: An automatic vacuum-relief apparatus for liquid suction systems includes a vessel defining a chamber filled with liquid in communication with a liquid flow line, a rotary shaft extending through the chamber to support a valve device adjacent to the liquid flow line and to move the valve device to open a relief-air flow channel to relieve increased suction caused by inlet blockage, and a piston on the rotary shaft responsive to suction increases within the liquid flow line and chamber to actuate shaft rotation. The valve device, chamber and relief-air flow channel are configured and arranged to cause a spurt of liquid from the chamber into the inlet while the valve device is moving from its isolating position toward its opening position upon inlet blockage, whereby the spurt of liquid pushes the blockage away from the inlet and the relief air reduces the suction.

Abstract: The present invention presents various novel approaches to solving the problems inherent in measuring biological pressures in high pressure systems. Thus, to protect a pressure transducer exposed to fluid flows at higher pressures than its overpressure rating, a novel valve is used that closes a protected leg in which the transducer is located. The various exemplary embodiments of such valves each have a high pressure input, one or more low pressure inputs, and an output. In operation, when a high pressure fluid flow occurs at a high pressure input, such valves automatically close the low pressure inputs. Alternatively, a novel transducer system is presented, which automatically limits the effective pressure sensed by a transducer to a certain maximum.

Abstract: A lubrication system includes an auxiliary lubricant tank 48, a supply conduit 58 extending from a source of lubricant 26 to the auxiliary lubricant tank. A reduced-G bypass line 108 branches from the conduit and enters the auxiliary tank at a first elevation E1. The system also includes an auxiliary tank discharge conduit 116, a portion of which resides within the tank. The resident portion has an opening 122 at least partially at a second elevation E2 higher than the first elevation.

Abstract: A system for regulating pressure supplied to a transmission control element, includes a control pressure source and line pressure source, a latch valve that opens and closes communication with the line pressure source in response to control pressure, and a regulator valve including a spool for regulating line pressure and producing control element pressure when the latch valve is closed, and an auxiliary piston responsive to line pressure and contacting the spool for connecting line pressure to the control element when the latch valve is open.

Abstract: A shuttle valve 10 includes a valve body 11, a first inlet port 12, a second inlet port 13, an outlet port 14, and a shuttle poppet 15. The inlet ports 12 and 13 may be connected to different sources of fluid pressure, and the shuttle valve 10 connects the higher pressure one of the inlet ports 12, 13 to the outlet port 14 and isolates the lower pressure one of the inlet ports 12, 13 from the outlet port 14. First valve members 26, 46 selectively open and close fluid communication between the first inlet port 12 and the outlet port 14. Second valve members 27, 47 selectively open and close fluid communication between the second inlet port 13 and the outlet port 14. The shuttle valve 10 includes cushioning cavities 50 and 51 and feedback passages 56, 59 and 60 to reduce shock or water hammer in the system.

Abstract: A fuel valve for a turbine engine, the valve has a fuel inlet connected to a supply of fuel and a purge inlet connected to a supply of purge air. Opening and closing apparatus within the valve selectively supplies air or fuel to a valve outlet. The opening and closing apparatus are movable in sequence from a first position where both the purge air and fuel to the outlet is disabled to a second position where the purge air is enabled and the fuel is disabled to a third position where the purge air is disabled and the fuel is enabled.

Abstract: A flow actuated valve includes a valve body, a diverter member, an actuator member, and a check disk. The valve body defines a first upper aperture, a second upper aperture, and a lower aperture. A check disk member connects to the actuator member to control the flow of fluid depending upon the direction of the flow of the fluid through the valve. When the check disk member is closed, the diverter member engages the actuator member to allow a first fluid to flow through the first upper aperture or to allow a second fluid to flow through the second upper aperture. In operation, the fluid is selected by changing the directional flow of the fluid to close the check disk member which causes the actuator member to engage the diverter member to either allow the first fluid source or the second fluid source to flow therethrough.

Abstract: A shuttle valve useful in connection with operation of underwater blowout preventers employs soft seals sealing an annulus between an inlet bore and the outer periphery of the shuttle to provide hydraulic function control from a high pressure low flow supply source such as a low volume positive displacement pump on a remotely operated vehicle without losing opposing inlet sealing and hydraulic fluid dump the opposing inlet during a return stroke of the pump.

Abstract: [Problem] The present invention provides a gas supply method by which a gas in a gas container can be effectively utilized. [Means for Solving the Problem] On the basis of: the maximum flow rate (a first preset flow rate (Q1)) and the minimum flow rate (a second preset flow rate (Q2)) at the place where the gas is used; a first preset pressure (P1) at which the gas can be supplied at a first preset flow rate (Q1); a second preset pressure (P2) at which the gas can be supplied at a second preset flow rate (Q2); a third preset pressure (P3) which is higher than the first preset pressure (P1); residual pressures (PA, PB) in gas containers (SA, SB); a supplied gas flow rate (Q); and the relationship between the residual pressures (PA, PB) and suppliable gas flow rates (QPA and QPB, respectively), the residual pressures (PA, PB) and the supplied gas flow rate (Q) are monitored and the gas supply is switched between the first gas container (SA) and the second gas container (SB).

Abstract: A unitary stacked shuttle valve body assembly 100 is disclosed that may be used in a well drilling blow out preventer circuit. The assembly includes substantially similar shuttle valves 9, 109 and 209 that may be assembled and arranged in various configurations to accommodate the requirements and restrictions of the particular circuit in which the assembly 100 may be used. The inlet ports 70, 170, 270 and the outlet ports 72, 172, 272 are substantially coaxial and are assembled with central seal connectors 76, 176 and 276 that permit rotation of the valve bodies 10, 110, 210 relative to one another. Feed passages 56, 156, 256, connector passages 59, 60, 159, 160, 259 and 260, and main passages 25, 125, 225 are provided with plugs of different configuration to permit changing port configuration to accommodate the requirements and restrictions of the circuit in which the assembly 100 is used.

Abstract: A fluid distribution control element for use in a ball check valve assembly having a valve housing defining a valve chamber and a first inlet opening spaced from a second inlet opening. The control element is arranged inside the valve housing to transition along a substantially linear path of displacement. The control element includes first and second obstruction elements each being configured to respectively fluidly seal the first and second inlet openings. The control element also includes a web portion, having a web length, which secures the first obstruction element to the second obstruction element. The web length is configured to restrict one of the first and second obstruction elements from sealing a respective inlet opening when the other obstruction element is sealing the other respective inlet opening. The web length is further configured to minimize the seat-to-seat distance the control element must travel along the linear path of displacement.

Abstract: A gas pressure sensor assembly for a gas regulator includes a plurality of selectable inlets, an outlet and a gauge. Each inlet receives pressurized gas from a different one of a plurality of pressurized gas storage containers. The outlet supplies gas to an appliance. The gauge senses a selected gas pressure in an inlet corresponding to the selected gas storage container and visually indicates a pressure of that gas storage container. The gas pressure sensor assembly includes a cooperating member at least partially housed within the gauge, a disc member rotatably responsive to a gas pressure and an sensing device. The sensing device is releasably connected to the gauge, is selectively actuated by movement of the disc member and is configured to provide an audible signal indicative of a generally empty status of the gas storage container.

Abstract: A check ball valve assembly is used to regulate fluid flow from two separate fluid sources to a single fluid outlet. The assembly utilizes a single check ball alternating between two check ball seats in two separate fluid passages. A check ball guide is installed at the intersection of the separate fluid passages and deflects the check ball from the pressurized passage to the non-pressurized passage to prevent backflow into the fluid source.

Abstract: In certain embodiments, an apparatus includes a control valve for regulating fuel flow. The apparatus can include a burner and a valve assembly. In some embodiments, the valve assembly includes a housing, which can define a first fuel input for receiving a first fuel from a first fuel source and a second fuel input for receiving a second fuel from a second fuel source. The housing can define a first fuel output for directing fuel toward the control valve, and can define a third fuel input for receiving a portion of either the first fuel or the second fuel from the control valve. The housing can define a first egress flow path and a second egress flow path, each for directing fuel to the burner. In certain embodiments, the apparatus includes a valve body configured to selectively permit fluid communication between the first and second inputs and the output and between the third input and the egress flow paths.

Abstract: A valve (1) with a AND gate function has a valve member (2) cooperating with moving passage members (23a and 23b) in a valve housing (3) in order to control connections between one outlet (A) and two inlets (E1 and E2). If the pressure difference present at the input side goes above a threshold value, the valve member (2) can thrust back one of the passage members (23a and 23b) against the stressing force of the stressing means (34a and 34b) in order to separate the outlet (A) simultaneously from both inlets (E1 and E2). Accordingly a safety and/or a logic function may be implemented.

Abstract: A product comprising a phase transfer valve, and wherein said phase transfer valve comprises an actuating valve housing having a housing interior; a liquid hydrogen inlet, a gaseous hydrogen inlet and a hydrogen outlet provided in said valve housing; an actuating valve slidably mounted in said housing interior; and wherein said actuating valve is moveable between a first position for sealing said gaseous hydrogen inlet from said hydrogen outlet and a second position for sealing said liquid hydrogen inlet from said hydrogen outlet.

Abstract: A valve for use between a first fluid side and a second fluid side is disclosed herein. The valve comprises a pair of subassemblies, each one slidable between a closed position and an open position. Each subassembly comprises a first component comprising a first component main body, a first component first end and a first component second end opposite the first component first end. A first component first extension is formed on each first component first end, the first component first extension comprising a diameter that is less than the diameter of the first component main body. Hydraulic pressure causes one subassembly to slide to its closed position, and causes it to engage the second subassembly, sliding the second subassembly to its open position.

Abstract: A selector valve selects between the supply of a primary pressure supply and a secondary pressure supply to a downstream use. The selector valve moves between a first position at which it supplies fluid from a primary line to the use, and a second position at which it supplies fluid only from a secondary line to the use. The selector valves moves through an intermediate position at which fluid is supplied from both supplies to the use.

Abstract: Check valve assemblies and related methods are described. A valve assembly comprises a housing having at least a first inlet passage and an outlet passage. A flow channel is disposed within the housing, with at least a portion thereof extending inward from the first inlet passage. A first check member is disposed within the first inlet passage and is movable along the flow channel between a closed position in which the first check member is disposed against a first valve seat and an open position in which the first check member is spaced from the first valve seat. In varying examples, movement of the first check member from the closed position to the open position is unopposed. Optionally, the housing can include at least a second inlet passage wherein a second check member is disposed. In an example, the second check member is continuously biased toward a closed position.

Abstract: A pressure balanced supply valve for use in a vehicular braking system. A housing defines a first chamber, a second chamber, a first fluid conduit for connection to a master cylinder, a second fluid conduit for connection to a hydraulic pump, and a third fluid conduit connected between the first and second fluid conduits. The second fluid conduit communicates with both the first chamber and the second chamber. A valve seat is defined in the third fluid conduit. A movable valve element is movable to a first position sealing against the valve seat to prevent fluid flow between the first and second conduits through the third conduit, and to a second position permitting fluid flow between the first and second conduit through the third conduit. The movable valve element is exposed to pressures in both the first and second chambers so as to be pressure balanced in operation.

Abstract: The present invention presents various novel approaches to solving the problems inherent in measuring biological pressures in high pressure systems. Thus, to protect a pressure transducer exposed to fluid flows at higher pressures than its overpressure rating, a novel valve is used that closes a protected leg in which the transducer is located. The various exemplary embodiments of such valves each have a high pressure input, one or more low pressure inputs, and an output. In operation, when a high pressure fluid flow occurs at a high pressure input, such valves automatically close the low pressure inputs. Alternatively, a novel transducer system is presented, which automatically limits the effective pressure sensed by a transducer to a certain maximum.

Abstract: A bypass/flushing valve for a hydrostatic system includes a valve body including a central bore, a shuttle valve located in the central bore, and a valve spindle disposed within the central bore. The valve body includes four ports each in communication with the central bore. The shuttle valve blocks flow through the central bore between a first port and a second port. When pressure at the second port is higher than at the first port, the shuttle valve moves to allow flow passage between the first port and the third port. When pressure at the first port is higher than at the second port, the shuttle valve moves to allow flow passages between the second port and a third port. The spindle is movable between a first position to block communication between the second port and the fourth port and a second position to allow for communication between the second port and the fourth port.

Abstract: The present invention presents various novel approaches to solving the problems inherent in measuring biological pressures in high pressure systems. Thus, to protect a pressure transducer exposed to fluid flows at higher pressures than its overpressure rating, a novel valve is used that closes a protected leg in which the transducer is located. The various exemplary embodiments of such valves each have a high pressure input, one or more low pressure inputs, and an output. In operation, when a high pressure fluid flow occurs at a high pressure input, such valves automatically close the low pressure inputs. Alternatively, a novel transducer system is presented, which automatically limits the effective pressure sensed by a transducer to a certain maximum.

Abstract: A fluid supply system or plumbing assembly includes a tap with at least one fluid inlet and a fluid outlet, and a diverter valve unit. The diverter valve unit is spatially separated from the tap and is connected to at least two different fluid sources, such as mains water and treated water. The diverter valve unit has at least two user selectable flow paths by means of which a selected fluid source can be supplied to the tap inlet.

Abstract: A shuttle valve useful in connection with operation of underwater blowout preventers employs soft seals sealing an annulus between an inlet bore and the outer periphery of the shuttle to provide hydraulic function control from a high pressure low flow supply source such as a low volume positive displacement pump on a remotely operated vehicle without losing opposing inlet sealing and hydraulic fluid dump the opposing inlet during a return stroke of the pump.

Abstract: In a directional control valve device, a first passage connects a second port with a first port by using a part of a movement path of a moving valve element when the moving valve element is in a position of a first end. A second passage connects the second port with the third port by using an internal passage of the moving valve element when the moving valve element is in a second end. The moving valve element is provided with a first check valve for permitting a flow in the internal passage only in the direction from the third port to the second port. When a fluid pressure is applied to the third port, the fluid pressure presses the moving valve element toward the second end so that the first passage is closed, and the first check valve is opened to open the second passage.

Abstract: Check valve assemblies and related methods are described. A valve assembly comprises a housing having at least a first inlet passage and an outlet passage. A flow channel is disposed within the housing, with at least a portion thereof extending inward from the first inlet passage. A first check member is disposed within the first inlet passage and is movable along the flow channel between a closed position in which the first check member is disposed against a first valve seat and an open position in which the first check member is spaced from the first valve seat. In varying examples, movement of the first check member from the closed position to the open position is unopposed. Optionally, the housing can include at least a second inlet passage wherein a second check member is disposed. In an example, the second check member is continuously biased toward a closed position.

Abstract: An apparatus for connecting a respiratory device with a patient is provided, including a breathing tube for insertion into a patient's trachea, an inflatable cuff positioned around the breathing tube, a connection tube connected to the cuff for providing inflating air flow thereto, a pressurized air reservoir, and a valve connected to the pressurized air reservoir and to the proximal end of the connection line. The valve includes an entry port associated with an entry differential force chamber, a first exit port associated with a first differential force chamber and coupled with the connection line, a second exit port associated with a second differential force chamber and coupled with the pressurized air reservoir, and a flexible membrane selectively sealingly separating the differential force chambers. The flexible membrane is configured to selectively connect the first and second differential force chambers to maintain a substantially constant air pressure in the cuff.

Abstract: When the pressure in a main fluid supply channel is lower than a no-load operation start pressure, the spool moves against the biasing force of a biasing member, and the area of opening of a auxiliary fluid supply channel is reduced with regards to opening of the internal flow channel. When the pressure in the main fluid supply channel rises and reaches a no-load operation start pressure, the area of opening in the auxiliary fluid supply channel with regards to opening of the internal flow channel becomes smaller and while connected to the main fluid supply channel, the auxiliary fluid supply channel is connected to the return flow channel. When the pressure in the main fluid supply channel rises above the no-load operating start pressure and reaches a no-load operation pressure, the auxiliary fluid supply channel is cut off from the main fluid supply channel.

Abstract: A double piston and belt type continuously variable transmission comprises a primary pulley provided with a primary piston chamber and a primary clamp chamber; a secondary pulley provided with a secondary piston chamber and a secondary clamp chamber; and an endless belt operatively put around the primary and secondary pulleys. A switching circuit is arranged to connect both the primary and secondary clamp chambers to either one of the primary and secondary piston chambers, which shows a higher hydraulic pressure than the other.

Abstract: The present invention presents various novel approaches to solving the problems inherent in measuring biological pressures in high pressure systems. Thus, to protect a pressure transducer exposed to fluid flows at higher pressures than its overpressure rating, a novel valve is used that closes a protected leg in which the transducer is located. The various exemplary embodiments of such valves each have a high pressure input, one or more low pressure inputs, and an output. In operation, when a high pressure fluid flow occurs at a high pressure input, such valves automatically close the low pressure inputs. Alternatively, a novel transducer system is presented, which automatically limits the effective pressure sensed by a transducer to a certain maximum.

Abstract: A gas supply apparatus including: a tank unit that includes a tank storing a gas and a discharge mechanism discharging the stored gas to the outside of the tank at a reduced pressure of the stored gas; a temperature detector that detects a temperature of the tank; and a supply regulator that regulates supply of the gas from the tank according to the detected tank temperature.

Abstract: A gravity controlled lubrication system for aircraft engines to supply a lubricant from a tank to a circulating system permitting lubricant to flow when the aircraft changes to an inverted flight condition.

Abstract: A valve system for use in a system including a first source of a first pressurized fluid and a second source of a second pressurized fluid includes a valve housing including a first inlet port adapted to be placed in fluid connection with the first source, a second inlet port adapted to be placed in fluid connection with the second source and an outlet port. The valve system further includes a backflow prevention system to prevent flow of the first pressurized fluid through the second inlet and to prevent flow of the second pressurized fluid through the first inlet port. The valve system is adapted to provide a fluid path between at least the first inlet port and the outlet port to enable fluid to be drawn from the outlet port to the first inlet port. Several of the valve systems of the present invention provide for flow from the first inlet port to the outlet port and concurrent flow from the second inlet port to the outlet port.

Abstract: The present invention provides methods and apparatus for mixing samples in-line in a microfluidic system, comprising methods of and means for introducing a first fluid sample into a flow-tube at a first end at a first velocity via a first conduit; methods of and means for introducing a second fluid sample into the flow-tube at the first end at a second velocity, the second velocity different from the first velocity, via a second conduit, wherein the first fluid sample and the second fluid sample converge in the flow tube to form an interface; whereby the first fluid sample and the second fluid sample mix at the interface within the flow-tube, wherein fluid flow at the first end of the flow-tube is laminar and fluid flow at a second end of the flow-tube is laminar, and wherein the flow-tube has a constant diameter between the first end and the second end of the flow-tube.

Abstract: The present invention presents various novel approaches to solving the problems inherent in measuring biological pressures in high pressure systems. Thus, to protect a pressure transducer exposed to fluid flows at higher pressures than its overpressure rating, a novel valve is used that closes a protected leg in which the transducer is located. The various exemplary embodiments of such valves each have a high pressure input, one or more low pressure inputs, and an output. In operation, when a high pressure fluid flow occurs at a high pressure input, such valves automatically close the low pressure inputs. Alternatively, a novel transducer system is presented, which automatically limits the effective pressure sensed by a transducer to a certain maximum.

Abstract: A pressure regulator (10) includes a changeover regulator (12) with plural inlets (16, 18). Inside the regulator, each inlet has a closure member (62) connected to a diaphragm (100) for control of the closure members (62) in response to pressure inside the regulator (12). Biasing members (56) are stabilized in position by either an apertured plate (102), a cup (104) or both. A changeover handle (19) depresses one spring (56) or the other to bias one closure member (62) open to admit gas from the associated inlet (16 or 18).

Abstract: A valve (10) comprises a housing (12) with a valve element (14) which normally fluidicly couples a low pressure operating device, such as a transducer (30) and tubing (34) to be coupled to a patient (36) along a first flow path (42) including a flexible control wall (58) which normally interrupts a second flow path (72) between a high pressure generating source such as an injector syringe (32) and the tubing (34), but which flexes, in response to high pressure excursions from the syringe (32) to allow the second flow path (72) to open as it flexes into the first flow path (42) to thereby restrict same thus providing protection to the transducer (30) during the high pressure excursion from the syringe (32).