Abstract: A hydraulic shock damper comprises a hydraulic cylinder and a piston having apertures and dividing the cylinder in upper and lower chambers. Through a flow channel the upper chamber of the cylinder is connected to a dashpot accomodating a partition element. The space being enclosed between the partition element and the closed end of the dashpot is filled with a pressurized fluid. Spaced around the said cylinder a second cylinder is provided, an open connection between the lower chamber of the first mentioned cylinder and the space between both cylinders being provided. Two branch lines are connected to the flow channel and emerge into a single line which in turn emerges into said space. In each branch line an externally controllable closure means and a non-return valve are arranged. Both non-return valves open in opposing fluid flow directions.

Abstract: An aspiration assembly having dual co-axial check valves for pumping medical fluids with a hypodermic syringe, the assembly having a main body with two passageways in offset relationship to each other, with the passageways coming together at a large central cavity within the main body, a central support structure mounted within the central cavity of the main body, a pair of flexible resilient valve disks engaged by the central support structure, and a body cap having an outlet passageway therein for complementarily enclosing the central cavity of the main body and for retaining the central support structure and dual valve disk in co-axial relationship.

Abstract: A valve structure according to the present invention is used for a hydraulic buffer provided with a member for partitioning the interior of a cylinder into two liquid chambers and having a plurality of ports for affording communication between both liquid chambers. The valve structure includes a valve body formed annularly of a leaf spring for opening and closing the ports and secured to the member on an inner peripheral portion thereof, a spring for biasing the valve body toward the member and a spring seat disposed movably between the spring and the valve body and having an abutting portion projecting toward the valve body at a side contacting the valve body. The valve body can flex about an outer peripheral edge of the abutting portion and an outer peripheral edge of the fixed portion.

Abstract: For use in pressurized fluid lines, an anti-siphon and back-flow prevention valve. A conduit is tapped into the line upstream of an outlet terminating in a ball-shaped housing. The housing receives check valve means arranged for insuring that fluid does not escape during normal operation of the line, but for admitting vacuum-breaking air in the event of line pressure loss.

Abstract: A check valve for disposition between a vacuum operated device and the intake of an auxiliary vacuum pump of an automobile which discharges into the crankcase of the engine of the vehicle. The check valve includes an elastomeric umbrella valve having a flexible lip which is self-biased to a closed position preventing backflow of air to the vacuum operated device and which is flexed to a normal open position by a pressure difference corresponding to pump operation with the integrity of the auxiliary vacuum system intact. A larger pressure difference corresponding to operation of the vacuum pump with the integrity of the auxiliary vacuum system breached flexes the lip of the umbrella valve to a control open position wherein airflow is restricted to only a control orifice of the valve the flow area of which orifice is predetermined to limit airflow to less than the rate at which air is scavenged from the crankcase of the engine.

Abstract: A faucet valve 10 includes a ball valve 28 seated in a valve chamber 18. The ball valve 28 has a plurality of apertures 46 circumferentially spaced about the control stem 32 which extends through an opening 60 in the cap assembly 48 of the valve housing 16. A check valve 66 is formed within the hollow interior 62 of the ball valve and includes a disc section 70 that mounts a flap valve 78. A shield formed by a cylindrical wall 80 downwardly depending from the disc section 70 and a snap ring 84 fitted on the lower end of the cylindrical wall protects the flap valve from undue water turbulence. Negative pressure in the supply inlet opens the flap valve 78 to draw air through passageway 64 formed by the apertures 46 and auxiliary opening 60 and hollow interior 62 of the ball valve seated in the valve chamber 18.

Abstract: A normally closed, one-way check valve having a body composed of two cylindrical containers which complement each other, each of said containers having a tubular projection with a liquid opening therethrough, one of said cylindrical chambers provided with a plurality of longitudinally extending ribs therealong for preventing sticking of a valve disc as contained within an assembled valve device, also further including a traverse bar for pressing against a valve disc. The other body component is provided with a pointed triangular support and also a plurality of radially extending ribs for preventing a valve disc from opening so far as to close off the egress port provided with said second element, together with a rubber resilient valve disc which is retained between the pointed triangular support and the traverse bar when the unit is assembled by sonic welding into a permanently assembled device.

Abstract: A preloaded check valve disposed in a valve body between an ink reservoir and a printhead has a valve opening pressure or "cracking" pressure at least sufficient to overcome the hydrostatic pressure due to gravity of ink in the reservoir. This prevents depriming or leakage of ink at the orifices of the orifice plate forming part of the ink ejecting mechanism. Ejection of ink during printing creates a pressure differential across the valve sufficient to cause it to open and replenish the ink supply at the ink ejecting mechanism.

Abstract: A mouthpiece for the inlet tube of a spirometer is formed to engage the inlet end of the tube and has a radially extending part or parts for preventing reverse fitting. An apertured valve seating has a valve diaphragm of flexible material for obstructing the return flow of air to the patient's mouth. The seating may have a projecting rim for engagement with the peripheral region of the diaphragm, and the diaphragm is preferably mounted so that it is planar on first engagement therewith. A ring may be arranged to be contacted by the diaphragm after initial bulging by back-pressure. Further deformation of the diaphragm is thereby controlled so that its peripheral region remains in engagement with the rim.

Abstract: A piezoelectric fuel injector for use in fuel injection systems of spark-ignition engines is provided with a normally closed valve assembly in the form of a reed valve. The valve assembly includes a valve plate having one or more outlet ports having an overall cross-sectional flow area sufficient to ensure an unobstructed flow path therethrough. The valve assembly also includes a generally flat, thin, resilient closure member cooperating with the valve set of the valve plate. The pressure wave created in the fuel in the pumping chamber upon excitation of the piezoelectric actuator propagates into the outlet ports to directly reach the thin closure member, which readily resiliently yields to permit a desired amount of fuel to be injected into the engine cylinders. The fuel injector is particularly suitable to be operated by a high-frequency drive signal in order to ensure precise metering of fuel quantity over a wide range of engine operating conditions.

Abstract: A non-return valve element comprises a one piece moulding of resilient rubber material, for example a synthetic rubber, which is shaped to include a relatively thick and hence rigid planar rib 1 of which the upper edge 1a includes a cylindrical protuberance 2 forming a reinforcement against longitudinal and transverse deflections. The lower edge 1b of the rib has two integral laterally extending wings 3 and 4, each of which is semi-circular in plan. The wings together in planform are circular and are designed to fit a cylindrical bore 5 provided in a fluid flow channel. The bore 5 is delimited from a narrower cross-section bore 6 by means of a shoulder 7 forming a seating for the wings 3 and 4, and an abutment for the ends 8 and 9 of the edge 1b of the rib 1.

Abstract: A hydraulic control apparatus, more particularly for operating a motor vehicle clutch release mechanism, comprising a master cylinder, a slave cylinder and a conduit connecting the master cylinder to the slave cylinder. The apparatus is in the form of separate modular units which are separately, but simultaneously, filled with hydraulic fluid after simultaneous evacuation of atmospheric air from the apparatus modular units and test of the integrity of the modular units, and the pre-tested and prefilled modular units are shipped unconnected to a user.

Abstract: A hydraulic control apparatus, more particularly for operating a motor vehicle clutch release mechanism, comprising a master cylinder, a slave cylinder and a conduit connecting the master cylinder to the slave cylinder. A leakproof quick-connect connector is placed between the master cylinder and the slave cylinder, preferably at the end of the conduit where it connects to the master cylinder or the slave cylinder, one member of the connector forming part of the master cylinder or slave cylinder. The apparatus, after assembly, is filled with hydraulic fluid, the two members of the connector being held momentarily engaged. After filling, the connector is broken, and the filled components are shipped to a user. After installation of the apparatus for operation of a mechanism such as a clutch release mechanism, the two connector members are reconnected, and the connector members having been provided with a one-way locking member can no longer be separated such as to preserve the integrity of the system.

Abstract: Several projected stripes, extending at regular intervals along the direction of fluid flow, are provided over the entire outer surface of a conical diaphragm except its outermost edge and neighboring section, and this diaphragm is set in a fluid-flow path with its outermost edge in tight contact with the wall of the fluid-flow path. The set of projected stripes not only arranges uniform flow of fluid but also prevents the diaphragm from being deformed under the fluid pressure.

Abstract: A flexible resilient valve disc is mounted in a valve body and is biased by its own resilience against an annular valve seat surrounding an inlet cavity in an inlet body member. The valve disc is adapted to be deflected away from the valve seat into an outlet chamber and an outlet body member. Mating pin and socket formations are formed axially on the body member. The valve disc has a central mounting hole which is received with an interference fit on the pin formation. Initially, the disc is flat, but is deflected into a cupped shape by engagement with the valve seat, when the valve members are assembled and bonded together. The inlet and outlet body members have inlet and outlet connections with inlet and outlet passages therein. The inlet and outlet connections are offset in a radially outward direction from the central axis of the valve.

Abstract: A small, reliable diverter valve that maintains a relatively constant flow through a spray nozzle in spite of water supply pressure fluctuations and that positively terminates flow from the faucet spout during hand spray operation. A variable elasticity cup seal keeps constant area passageway to the spray nozzle in spite of water supply fluctuations. A normally open path, moreover, enables air to flow from the spout into the water supply system in conditions of negative supply pressure and thereby assists the cup seal in preventing backflow from the spray nozzle into the fresh water supply.

Abstract: A hydraulic control apparatus, more particularly for operating a motor vehicle clutch release mechanism, comprising a master cylinder, a slave cylinder and a conduit connecting the master cylinder to the slave cylinder. The apparatus is in the form of separate modular units which are separately filled with hydraulic fluid, and the filled modular units are shipped unconnected to a user. Each modular unit is provided with a leakproof quick-connect connector member, through which filling of the modular unit may be effected, and which mates with a complementary leakproof quick-connect connector member of another modular unit, such that after installation on a utiization device, a motor vehicle for example, complementary connector members are reconnected, thus opening ports in each connector member placing each member in fluid communication with the other. Preferably, the two connector members are provided with a one-way locking arrangement preventing separation of the connector members after coupling.

Abstract: An exhaust valve for a diving suit includes a valve seating disc having a concave annular valve seat sealing surface adjacent its rim, and a flexible diaphragm sealingly disposed adjacent the sealing surface. An axially resilient sleeve is attached at its ends to the inlet portion of the housing and the seating disc. Axial compression of the sleeve moves the disc and diaphragm away from a normally contacting annular rim in the housing to permit air under pressure to exit the diving suit and flow radially between the sealing rim portion of the diaphragm and the sealing surface of the disc, then to exit the valve.

Abstract: A fluid-pressure-operable device 1 includes two relatively-movable components 2, 3 defining a variable-volume working chamber 9. A sealing element 5 of elastomeric material is carried, or formed, by one of the components and is in sliding and sealing engagement with the other of the components normally to resist escape of fluid under pressure from chamber 9 to the exterior thereof. That face 15 of element 5 remote from the chamber is so provided with channel 16 that as pressure in the chamber increases the element is permitted progressively to deform and some of the material of the element thus displaced is then accommodated by the channel. When the pressure exceeds a predetermined value, deformation of the element is such that sealing engagement of the element with the other of said components is broken so that the pressure in chamber 9 is relieved to the exterior thereof.

Abstract: A valve plate for a plate-type non-return valve includes at least one valve closure portion and at least one resilient flexible guide arm connecting with the valve closure and the guide arm or arms are configured to include a continuously curved portion generally extending as a spiral from a central hub.

Abstract: A variable-delivery compressor of a swashplate type having compression chambers wherein compression is effected by reciprocating movements of double-headed pistons slidably engaging a rotating swashplate in a cylinder block. The cylinder block defines compression chambers in cooperation with front and rear valve plates which have discharge ports communicating with front and rear discharge chambers one of which serves as delivery-adjusting discharge chamber. Delivery-adjusting discharge valves are disposed in the delivery-adjusting discharge chamber and carried by an actuator member which is movable between operative and inoperative positions at which the delivery-adjusting valves are operative and inoperative to close and open the discharge ports in the corresponding valve plate. The corresponding valve plate comprises a portion defining a recess opposite to each delivery-adjusting discharge valve.

Abstract: Integrated flapper check valve assembly consisting of cylindrical flapper check valve housing with valve seats and air passage ports, cylindrical flapper check backer with air passage ports, and intermediate flapper check valve with flat multi-leaf design.

Abstract: A pumping apparatus for pumping heavy viscous chemicals and the like. The apparatus has a pump means having means for attachment to a container of the viscous chemicals and the like, and has driving means including a motor and means for detachably connecting the driving means to the pump means so that the pump means and driving means are separable, and the driving means may be used with other pump means.

Abstract: Stage for a system for distributing pneumatic control signals by electrical means, comprising a large number of associated stages. Each stage comprises a removable electrical valve (141) having an electro-magnet (33) of very low power, and a fixed socket (5) into which it fits: a pneumatic amplifier (57) is housed in the body (51), of the socket and feeds relatively large amounts of fluid to an outlet connector (26) when it is activated by the outlet of a low flow pneumatic switch (40); a non-return valve (88) protects the amplifier against pressure perturbations in the discharge duct (4). Numerous thin stages of a thickness close to 17.5 mm. can with advantage be used as an interface between a pneumatic installation (28) and a control center (24) supplying low level electrical signals.

Abstract: A fluid check valve has a disk shaped resilient valve element mounted along the flow path of the valve to permit the flow in one direction only. The disk is maintained normally in a dish shape, with dished disk being biased toward and against the valve inlet to normally bias the valve in a closed configuration. The operating characteristics of the valve, such as cracking pressure and minimum flow rate, are adjustable by a disk mount which enables the biasing force to be varied. The mount supports the disk and enables slight adjustable movement of the disk axially toward and away from the inlet so as to vary the degree of dishing of disk and, therefore, its resilient biasing force. In another aspect of the invention the valve is provided with improved outlet characteristic which minimize the back pressure of the valve and enable it to be responsive quickly even at very low flow rates and pressure differentials.

Abstract: A rotary pump for pumping liquid which includes a rotor combination in the form of a vane pump or gear and rotor with pumping chambers disposed circumferentially around the rotor. The chambers progressively increase in the inlet area and ensmall in the outlet area. Resilient means are interposed between the ensmalling chambers and an outlet to block backflow of the pressurized outlet liquid into pumping chambers containing vaporized liquid instead of solid liquid, thus reducing the pump noise under conditions of vaporization termed "cavitation".

Abstract: A ventilator device for allowing escape of air from enclosed spaces such as a building includes a unitary housing provided with an insert for controlling the flow of fluid therethrough. The insert comprises a pair of insulative, tubular sleeves between which there is sandwiched a flow control valve. The valve may include a fabric-like foraminous membrane which permits passage of moisture laden air outwardly through the ventilator but prevents moisture in the form of liquid or droplets from returning into the building through the ventilator. Alternatively, the valve may comprise a flexible member which deflects in response to a pressure differential within the housing to allow rapid escape of air from the roof to the surrounding environment.

Abstract: A normally closed, one-way check valve having a body composed of two cylindrical containers which complement each other, each of said containers having a tubular projection with a liquid opening therethrough, one of said cylindrical chambers provided with a plurality of longitudinally extending ribs therealong for preventing sticking of a valve disc as contained within an assembled valve device, also further including a traverse bar for pressing against a valve disc. The other body component is provided with a pointed triangular support and also a plurality of radially extending ribs for preventing a valve disc from opening so far as to close off the egress port provided with said second element, together with a rubber resilient valve disc which is retained between the pointed triangular support and the traverse bar when the unit is assembled by sonic welding into a permanently assembled device.

Abstract: The check valve is used to control the flow of fluid through a cylindrical passageway having a cylindrical wall surface and comprises an elongate umbrella valve member having a frusto-conical shaped skirt extending radially outwardly and axially of the valve member. The skirt is positioned to extend in the downstream direction of the flow of fluid through the passageway and in frictional, sealing engagement with the cylindrical wall surface of the passageway but yet being flexible enough to deflect inwardly under fluid pressure to allow fluid to flow downstream past the skirt.

Abstract: A check valve assembly is disclosed having a valve chamber with an inlet port and an outlet port. An elastomeric umbrella valve is contained in the chamber between the ports and is attached by an integral stem in a preloaded condition to normally close the inlet port and be deflectable in response to differential fluid pressure acting in one direction to open same to permit forward fluid flow therethrough past the valve and through the chamber to the outlet port. An inwardly projecting retention arrangement formed in the chamber retains the valve in operational relationship with the inlet port in the event the valve becomes unattached so that any backward flow from the outlet port still forces closure of the valve on same. A bypass channel arrangement also formed in the chamber maintains forward fluid flow past the valve to the outlet port in the event the valve becomes unattached.

Abstract: A liquid reservoir for a hydraulic master cylinder, having a body with a detachable cap for refilling the reservoir, and a diaphragm secured in position by the cap and dividing the reservoir into an air chamber, vented to atmosphere via a hole in the cap and a liquid chamber connected to the master cylinder. An inlet port is provided in the wall of the reservoir for initial charging of the liquid into the liquid chamber without removal of the cap, the port being closed by a plug after the liquid reservoir has been filled. The method of filling a hydraulic control system which has such a reservoir is by the application of vacuum to the system via the inlet port, introducing liquid into the system through the port and subsequently sealing the port with the plug.

Abstract: A variable delivery compressor having therein a plurality of compression chambers is adapted for compressing a refrigerant gas of a cooling circuit. The compressor has a first delivery chamber communicating with the compression chambers by way of a fixedly arranged valve and a second delivery chamber communicating with the compression chambers by way of a movably arranged delivery valve. This movable valve is formed to include a base portion, a plurality of reed portions formed to radially extend from the outer circumference of the base portion and arranged to face delivery ports, and at least one protrusion formed to radially extend from the outer circumference of the base portion for suppressing the warp of the base portion.

Abstract: A liquid reservoir for a hydraulic master cylinder, having a body with a detachable cap for refilling the reservoir, and a diaphragm secured in position by the cap and dividing the reservoir into an air chamber, vented to atmosphere via a hole in the cap and a liquid chamber connected to the master cylinder. An inlet port is provided in the wall of the reservoir for initial charging of the liquid into the liquid chamber without removal of the cap, the port being closed by a plug after the liquid reservoir has been filled. The method of filling a hydraulic control system which has such a reservoir is by the application of vacuum to the system via the inlet port, introducing liquid into the system through the port and subsequently sealing the port with the plug.

Abstract: An overpressure safety valve assembly for use during heart surgery is disclosed. The assembly comprises an elongated tubular body portion having an inlet end, and an outlet end and an unidirectional valve disposed therebetween. A relief valve portion is joined to and in flow communication with the tubular portion. The relief valve portion includes a first relief valve configured to open if the pressure within the overpressure safety valve diminishes below a predetermined level, and a second relief valve configured to open if the pressure adjacent the outlet end exceeds a predetermined level.

Abstract: A damping force generating mechanism in a hydraulic damper includes a housing containing therein oil and an oil chamber partitioning member such as a piston. The mechanism includes a communicating passage provided in the oil chamber partitioning member and defining an annular valve seat on one end thereof and an annular valve plate provided on one end of the communicating passage and being deflectable toward and away from the valve seat for permitting the oil to flow in the communicating passage in one direction. The plate valve consists of a plurality of mutually overlapping annular plates, and at least one of the annular plates is deflected in the direction separating from the valve seat by a projection member which also is one of the annular plates.

Abstract: A liquid-flow control valve with pressure-sensitive gas-bleed apparatus having a debris-catching feature. Included is a disc sealingly seatable selectively against a valve seat to open and close the valve. Apertures, which extend through the disc, remain open when the disc is seated on the seat. An aperture closure device, disposed adjacent the disc on the side from which fluid normally flows, has a pressure-responsive flex web biased by natural internal relaxed-state memory to form, in cooperation with the disc, a cavity which communicates with the apertures. The web has openings which are offset from the apertures when viewed along the adjustment axis of the valve and which communicate with the cavity. The web is moveable under the influence of liquid pressure from within the body toward the disc to collapse the cavity and to close the apertures when the disc is seated on the seat.

Abstract: A reed valve assembly is provided with a reed sandwiched between two base members, e.g. a valve plate and a cylinder head of a compressor. The reed is clamped between the two members at a central part whereby both free ends of the reed can flex. The base members are so structured that one free end of the reed forms an intake valve members and the other a discharge valve member, whereby a single reed serves both as an intake valve member and as a discharge valve member. The invention also avoids rivets or the like elements by securing the reed to the base solely by the clamping action of properly recessed faces of the two base members.

Abstract: A breathing valve for the selective entry of a gas to be inhaled and for the exit of exhaled gas, which utilizes a rolling diaphragm and flapper valves for its workings which are quiet and are constructed so as to be unlikely to freeze up or become sticky.

Abstract: A respirator face mask formed from a silicone or other vulcanized rubber with a multi-compound curved face seal having a superior configuration for facial fit. The mask is held by four support buttons and two straps attached thereto having a reverse leverage pulldown effect to pull the mask into contact with the facial area. The four attachment means for the straps are eccentric buttons having an undercut that overrides a loop that can be easily disassociated when the attachment loop is reversed and pulled over the button. A concave configured sealing diaphragm on the exhalation valve provides for substantially uniform opening with less effort than is normally encountered in such valves. A staggered anti-inversion rib on the concave underside of the exhalation valve prevents the diaphragm from inverting to a convex configuration. The valve includes an exhalation valve stack and vent that can be covered at a sharply chamfered opening to provide for a pressure fit test.

Abstract: The invention relates to a damper valve for arrangement in a liquid conduit to control flow through the conduit in both directions, and of the kind comprising an apertured port plate with resilient flaps covering the ports so that fluid flow can only take place unidirectionally through a flap covered port. The valve also has a pair of main bump ports (11) covered by a centrally anchored elongate metal leaf (12) disposed on a first side of the port plate (10); a pair of rebound ports (13) similarly covered by a centrally anchored elongate metal leaf (14) disposed on the second side of the port plate (10); said pairs of bump and rebound ports (11 and 13) being of generally similar size.

Abstract: An infant's feeding bottle employing a valve to assure approximately atmospheric pressure within the bottle during feeding, the valve and valve stem being of like material and of simple unitary construction whereby to avoid numerous problems such as rust, sticking, and development of unsanitary conditions associated with other valves under like conditions of use.

Abstract: This invention is directed to a dispenser for viscous fluids.

Abstract: The invention relates to a shock absorber mounted between a suspended part and an unsuspended part of a vehicle and specifically a telescopic hydraulic shock absorber comprising a damping piston slidingly mounted in a cylinder. A compensation piston cooperates with the cylinder in order to maintain the damping piston and the cylinder in a given relative position during a variation in the load or centering of the vehicle. The compensation piston has at least one passage controlled by at least one valve sealing the passage to permit the normal operation of the shock absorber during a rapid deformation of the latter as a result of unevennesses of the road. One or more return springs maintain the damping piston at rest in a middle position relative to the cylinder facing a given zone of the latter.Application to vehicle shock absorbers.

Abstract: An oil separator in combination with an oil lubricated vacuum pump. The separator includes a hollow housing having one end disposed adjacent the suction opening of the pump and the other end adapted for attachment to a vacuum line. A valve seat comprises an internal surface of the housing, and a resilient elastic sealing element having a relatively low mass is positioned under tension on the valve seat between the seat and the suction opening. The sealing element permits a stream of air from the vacuum line to enter the suction opening of the pump while preventing oil from the pump from passing into the vacuum line.

Abstract: The present invention describes a vented check valve for use with post-mix carbonators. The vented check valve is a fail safe device which will vent carbon dioxide or carbonated water to the atmosphere when a back flow condition occurs. The vented check valve of the present invention includes a flexible valve diaphragm having a first valve seat portion around the annular portion of the diaphragm and a second valve seat portion in the center thereof. The first valve seat portion is utilized to open and close the main water inlet by permitting the edges of the diaphragm to flex in response to the pressure of water flowing in a first direction. The second valve seat portion is disposed in cooperation with a vent passage and seats firmly on the vent passage while water flows in the first direction, but unseats from the vent passage permitting the water to flow out of the valve, through the vent passage to the atmosphere when a back flow condition occurs, i.e.

Abstract: A synthetic leaflet aortic and mitral heart valve for use in replacement of diseased natural heart valves having a flexible, curved framework, a flexible membrane attached to the framework and fixation means for attaching the valve to the tissue annulus. The framework consists of at least three curved flexible valve struts, each joined together at one end to a common central point of the valve and extending in the same direction radially at equal angles so that the free ends are unattached and at a distance from one another. The free ends are provided with sewing pads for artificial attachment of each free end separately to the natural tissue annulus or to an artificial annulus reconstruction ring which itself is sutured to the tissue annulus to restore its symmetry.

Abstract: In a fluid reservoir for a brake master cylinder, a cap member of elastic material is coupled over the upper opening of a casing, and a diaphragm seal member is coupled within the cap member to subdivide the interior space of the casing into upper and lower chambers. The seal member is provided at its outer periphery with an inlet check valve assembly and at its inner periphery with an outlet check valve assembly. The inlet check valve assembly is characterized by an annular valve seat in the form of a lower stepped portion in the cap member, a cylindrical retainer secured to the outer periphery of the seal member and having an annular flange facing to an upper stepped portion in the cap member, an annular lip of elastic material integral with the flange of the retainer, and a spring loading the retainer toward the upper stepped portion.

Abstract: A rotary fluid pump of a non-lubrication type having a pump cavity formed within a cylindrical stator housing and a pair of recessed end head assembles. A drive shaft is eccentrically journalled in the end heads with a rotor mounted thereon with vanes slidably disposed in radial grooves in the rotor. A pair of sealing plates disposed between the ends of the stator having and the end heads divide the pump cavity into a pair of end chambers and an intermediate rotor chamber. An outlet port provides fluid communication between the rotor chamber and a discharge hole in one of the end chambers so that fluid passage for discharge to the atmosphere is provided through the rotor chamber, outlet port, end chamber and discharge hole.

Abstract: A blood sampling device having a valve assembly which prevents the backflow of blood into a patient, and which is especially suitable for multiple sample collection. The valve assembly includes a mounting structure for a valve member, a chamber to house the valve, and a valve which has a resilient skirt allowing fluid flow only in one direction. The valve member is prevented from cocking by a protruding portion which fits within a recess of the mounting structure and by valve positioning members within the valve chamber.

Abstract: A combination vacuum lift pump and siphon for handling liquids, comprising a pump cylinder having an inlet disposed near one end and an outlet adjacent to but spaced from the other end, a piston reciprocatable in the cylinder, and a plunger and handle connected therewith, and a pair of check valves, one of which is associated with the piston and is operable to be closed when the plunger is lifted in the cylinder, and the other of which is disposed at the cylinder inlet and is operable to be closed when the plunger is lowered in the cylinder. The outlet of the cylinder is spaced a short distance from the upper end thereof, such that for siphon operation the piston and its check valve can be moved to a position in the cylinder which is beyond the location of the outlet. Accordingly, the flow of liquid by-passes the piston check valve completely, and the latter thus does not act in such a manner as to restrict the siphon flow, as was the case in many other constructions.