Abstract: A suction valve for a positive displacement pump. Two springs are used to actuate a valve plug. A first spring has an uncompressed length greater than a distance between a spring retainer and the valve plug, providing a preload force closing the valve. A second spring has an uncompressed length less than the distance between the retainer and the plug, providing closing force to the plug only after a preselected valve lift. The first spring is relatively light and permits rapid opening of the valve to avoid cavitation. The second spring increases the effective spring constant when the valve is open to prevent flutter and to assist in closing of the valve upon commencement of a discharge pump stroke.

Abstract: Disclosed is a hydraulic pump for a brake system including a piston installed in a bore formed in the modulator block having an inlet and an outlet such that the piston can reciprocate and having a channel communicating with the inlet, a plug installed in the bore for dividing the inside of the bore into a pressure chamber, in which the piston is located, and a discharge chamber communicating with the outlet and having an orifice communicating the pressure chamber and the discharge chamber with each other, and a discharge valve installed in the discharge chamber for opening and closing the orifice, wherein a filter for filtering oil, fed into the bore through the inlet, is installed in the bore, and surrounds the outer surface of the piston so as to guide the piston. Since the filter for filtering the oil serves as a guide member guiding the piston as well as a filtering member, the hydraulic pump reduces the number of components and reduces an occupied space.

Abstract: A compressor may include a compressor body defining a compression cylinder, a compressor head coupled to the compressor body, and a valve plate assembly disposed between the compressor head and the compressor body. The valve plate assembly may include a first valve plate formed as a unitary casting and defining a suction chamber exposed to a suction pressure region of the compressor.

Abstract: A hermetic compressor having an improved discharge valve assembly to efficiently limit deformation of a stopper caused by a reed valve while achieving efficient opening operation of the reed valve. The hermetic compressor includes a compression chamber and a discharge valve assembly.

Abstract: A suction structure is provided for allowing refrigerant from a suction pressure region in a piston type compressor. The compressor includes a rotary valve. The suction structure includes a shifting device which shifts between a connecting state and a disconnecting state. In the connecting state an outlet of a supply passage of the rotary valve is connected to a suction pressure region and in the disconnecting state the outlet of the supply passage is disconnected from the suction pressure region. The shifting device includes a valve body, a return spring, and a permanent magnet. The valve body is movable between a connecting position and a disconnecting position. The return spring urges the valve body from the connecting position toward the disconnecting position. The permanent magnet attracts the valve body by magnetic force from the connecting position toward the disconnecting position.

Abstract: This invention relates to the use of elastomers with the sealing element of reciprocating gas compressor valves to increase the reliability of the gas tight seal within the reciprocating gas compressor valve and to increase the useful life of reciprocating gas compressor valve. The elastomeric material is either used as a coating layer on the sealing element of the reciprocating gas compressor valve, or as the entire sealing element. The elastomeric material acts as a cushion to reduce the wear on the sealing element, provides a superior gas tight seal, and is more tolerant of entrained dirt or liquids in the gas stream thereby increasing the operable life of the reciprocating gas compressor valve. Reducing the mean time between reciprocating gas compressor valve failures results in longer reciprocating gas compressor run times for the user, increased revenue generation for the user and safer operation of said equipment.

Abstract: A fuel pump includes a pump housing having a compression chamber. A plunger is axially movable in the pump housing for pressurizing fuel in the compression chamber. A discharge valve is configured to open to supply fuel from the compression chamber to an internal combustion engine when pressure in the compression chamber is more than predetermined pressure. A fuel passage is configured to communicate a downstream of the discharge valve with an upstream of the discharge valve. An in-passage member is accommodated in the fuel passage. The in-passage member includes multiple members, which are combined to define a throttle portion for restricting fuel, which returns from the downstream of the discharge valve to the upstream of the discharge valve.

Abstract: A valve mounting arrangement for a refrigeration compressor which presents a compression chamber closed by a valve plate having a suction orifice closed by a valve element having a mounting end portion. The mounting arrangement comprises: a first retaining means to retain the mounting end portion of the valve element inside a receiving recess of the valve plate; and at least one orientation projection carried by receiving recess and/or the mounting end portion of the valve element and to be fitted into an orientation recess in the other part; and/or a second retaining means provided between the receiving recess and the mounting end portion of the valve element, so as to avoid the latter from moving from the receiving recess before mounting the first retaining means.

Abstract: A housing for use in high-pressure fluid applications, comprising a first passage defining a first axis (P1) and a second passage defining a second axis (P2), wherein the first and second passages intersect at an opening defined by an intersection at one end of the second passage. When sectioned on a plane normal to the second axis (P2) and not intersecting the first passage, the intersection defines an ellipse (E) in the plane and centred on the second axis (P2), the ellipse having a major axis equal in length to the width (D2) of the intersection and a minor axis equal in length to the height (D1) of the intersection. A wall of the intersection describes a curve in the plane, the curve passing through the points where the major and minor axes of the ellipse (E) meet the perimeter of the ellipse (E), and through points which lie outside the ellipse (E) and which are offset from the ellipse (E) by an offset distance (K).

Abstract: The high-pressure pump has at least one pump element which has a pump plunger which is driven in a reciprocating motion and defines a pump working space into which fuel is drawn in from a fuel feed via an inlet valve during the suction stroke of the pump plunger and from which fuel is displaced into a high-pressure region via an outlet valve during the delivery stroke of the pump plunger. The inlet valve and/or the outlet valve has a valve member at least approximately in the shape of a ball which interacts by means of a sealing surface with a valve seat arranged in a valve housing. By means of the valve member, in the open state, when said valve member is lifted with its sealing surface from the valve seat, a first cross section of flow is cleared between the valve member and the valve seat, and downstream of the first cross section of flow, a second cross section of flow is formed between the valve member and the valve housing.

Abstract: A pump (60, 160) has a pair of working members (preferably diaphragms 1, 2, 101, 102) and a pump chamber (3, 4, 103, 104) associated with each working member is communicated via check valves (32-35, 132-135) to a suction manifold (30, 130) and to an outlet manifold (31, 131). A drive mechanism (10, 110) couples the working members so that they reciprocate together and a first of the working members performs an outlet stroke while a second of the working members performs a suction stroke. The suction and outlet manifolds (30, 130, 31, 131) are incorporated in a manifold assembly that connects the pair of diaphragms (1, 2, 101, 102) for coordinated reciprocation. A pair of manually-operated levers (J, 8, 107, 108) are connected together for opposite reciprocation and are drivingly connected to the working members (1, 2, 101, 102).

Abstract: A double-acting, simplex, fluid handling pump is designed to facilitate an optional configuration as either a plunger pump or a diaphragm pump. An injection molded plastic pump body comprises two bilaterally symmetrical halves that include internal pockets and grooves for clamping and retaining first and second generally identical valve assemblies at opposing end portions of the pump body. When configured as a plunger pump, first and second plunger are arranged to move 180 degrees out-of-phase with respect to one another within stationary guide sleeves that are clamped within the pump body where one plunger effecting a suction stroke while the other effects a compression stroke. When configured as a diaphragm pump, the plungers are removed from the connecting rods and replaced by diaphragms and a change is made in the valve casing employed but a majority of the remaining parts of the pump assembly remain unchanged from what is used in the plunger pump.

Abstract: A priming pump for fluid delivery arranged with a base defining a flow inlet, a flow outlet, and a control valve positioned therebetween. The priming pump includes a housing assembled to the base with an inlet flow valve positioned in an inlet valve compartment and an outlet flow valve positioned in an outlet valve compartment. The valve compartments are in communication with a plunger chamber including an axially movable plunger. A spring-biased control knob is assembled to the plunger and to the control valve for controlling its position between either a direct-flow orientation or a by-pass orientation. With the control valve in the by-pass orientation, upward movement of the control knob draws fluid into the inlet valve compartment and into the plunger chamber. The down stroke of the control knob pushes the fluid out of the plunger chamber.

Abstract: A linear compressor has a hollow piston with crown and sidewall. The piston reciprocates in a cylinder. A piston rod connects the piston to a spring. A connection between the piston rod and the piston transmits axial forces directly to the piston crown. The connection transmits lateral forces to the piston at an axial location away from the piston crown. The connection allows rotational flexibility between the piston and the piston rod transverse to and uniformly around the piston reciprocation axis. Other improvements in or relating to linear compressors are disclosed and claimed.

Abstract: An apparatus and method for compressing a cryogenic media is disclosed. A compressor includes a compressor chamber surrounded by a cylinder wall in which a compressor piston is moved in a linear manner, a suction valve and a pressure valve, which are arranged in the region of the lower end position of the compressor piston, and a liquid chamber which at least partially surrounds the compressor chamber. The cylinder wall defines at least one opening, which corresponds to the liquid chamber, and at least one opening, via which the gaseous medium can be extracted from the compressor chamber, where the openings are located at points on the cylinder wall that are passed by the compressor piston.

Abstract: The present invention is aimed to provide a pump which can not only obtain high discharging pressure and large capacity but obtain a substantially non-pulsating flow with a miniaturized configuration and even if the pump is operated with low power.

Abstract: The invention relates to an outlet connection of a fluid high-pressure light, in particular a high-pressure line for fuel, and comprises an outlet bore, an outlet valve that is situated in said bore, the valve element of which can be displaced in said bore and can be controlled by the pressure prevailing in the high-pressure line in opposition to the action of a spring element, a spring retainer inserted into the outlet bore and fixed in the latter and on which the spring element is supported, and an external thread.

Abstract: A rotary pump for producing a pressure medium flow for a consumer, includes a pump housing in which a curved ring is inserted. A rotor is rotatably borne on a drive shaft in the curved ring. The rotor carries displacement elements at a tangential distance to one another which form a pump chamber between the rotor and the curved ring with a suction opening. A pressure medium-activated adjusting device is operable for changing the eccentricity of the curved ring relative to the rotor, and includes a first pressure chamber and a second pressure chamber fluidically and tangentially distanced from the first pressure chamber The pressure in the first and second pressure chambers is controlled by a flow control valve, the low pressure chamber of which communicates with a first control line on a downstream side of a metering orifice.

Abstract: The invention provides a compressor that can reduce occurrence of vibration and noise due to self-induced vibration of an suction valve at the time of a low flow rate surely with an inexpensive structure. In the compressor according to the invention, an opening regulating valve 40 provided in a refrigerant suction channel 13c to a cylinder 11a is formed by an elastically deformable spiral member 41, and intervals of spiral portions 41a of the spiral member 41 are changed according to a flow rate of a refrigerant, whereby an opening of the channel 13c is regulated. Thus, it is possible to reduce occurrence of vibration and noise due to self-induced vibration of an suction valve 14c at the time of a low flow rate surely, and it is possible to simplify a structure of the opening regulating valve 40.

Abstract: A pump powered partly by a mechanical drive and partly by a pressurised fluid flow, offering energy savings up to 90% in reverse osmosis systems. The pump consists of one or more piston-in-cylinder assemblies. One face of each piston provides a pumping action while a pressurised driving fluid flow is applied to the opposite piston face, thus supplementing the drive force applied to each piston via a piston rod. Input and output of the pumped flow is controlled by pump valves of a non-return poppet type operated by the pumped flow. Input and output of the driving fluid is controlled by poppet-type valves controlled by connection to the pump valves. There are means to control piston movement relative to the cylinder and to the piston rod, and a two-part pump valve to simplify connection to the motor valves.

Abstract: A fluid discharge pumping apparatus includes: a drive mechanism; a cylinder; an outflow valve mechanism and an inflow valve mechanism coupled to the cylinder; a piston member inside the cylinder; and a piston-supporting member attached to the piston member driven by the drive mechanism to move the piston member. The inflow valve mechanism opens when the interior of the cylinder is depressurized, whereas the outflow valve mechanism opens when the interior of the cylinder is pressurized.

Abstract: A hydraulic piston pump in which a cylinder port (4b) can be communicated with a discharge port (9) after a system pressure (Po) and a chamber pressure (Pi) in a cylinder bore are in an equilibrium state. A through-hole (16) opened in that surface of a valve plate (7) on which a cylinder block (3) slides is communicated with one end surface (21a) side of a balance valve (20), and the system pressure (Po) on the discharge port (9) side is supplied to the other end surface (21b) of the balance valve. A balance piston (21) is built-in in the balance valve, and the balance piston (21) slides by a pressure difference between the chamber pressure (Pi) in the cylinder bore (4) and the system pressure (Po). Before a cylinder port (4b) is communicated with an oil guiding groove (15), the chamber pressure (Pi) and the system pressure (Po) can be brought into an equilibrium state by actuation of the balance piston (21).

Abstract: A fluid end for a high-pressure pump including a unitary body with a plurality of horizontal passages each for receiving a reciprocating plunger at one of its ends and a pressure relief valve at the other of its ends. The body is provided with a corresponding number of vertical passages each of which intersect one of the horizontal passages and contains a suction valve at its bottom and a discharge valve at its top. A suction manifold is hingedly attached to the bottom of body to provide a flow of fluid into the body via the suction valves. A discharge passage intersects the vertical passages and receives fluid pressurized by the plungers via discharge valves and ports such from the fluid end.

Abstract: The invention relates to a device for pumping a fluid into a bioreactor. Polsatile pumping is made possible by valve arrangement so that growth of the cells in the bioreactor is increased. Pumping function can be achieved though several mechanisms. A piston can be displaced in a cylinder, especially by an electromagnet, wherein a permanent magnet or likewise an electromagnet can be arranged in the piston. The piston can also be displaced by compressed air. An elastic, hollow body can also be provided, wherein said hollow body can be deformed by mechanical electromagnetic forces so that pumping function is achieved by a change in volume. The pumping device can also be used as implant for assisting or replacing heart function.

Abstract: A diaphragm is provided in a pump case so as to define a pump chamber communicated with an external member having an air chamber. A motor actuates the diaphragm to introduce air to the air chamber. An exhaust valve exhausts air in the pump chamber to lower a pressure in the air chamber. In the exhaust valve, an exhaust port is communicated with the pump chamber. A flexible valve body having a larger size than the exhaust port is disposed so as to close the exhaust port from a side facing the pump chamber. An actuator is disposed in an opposite side to the valve body relative to the exhaust port, and driven by the motor so as to be movable between a first position retracted from the exhaust port and a second position passing through the exhaust port so that the valve body is actuated so as to open the exhaust port. An urging member always urges the actuator to the first position thereof.

Abstract: A universal air pump includes a pump; a head mounted to the pump and having a central hole and an air inlet at a side wall thereof; a cylindrical block pivotably fitted in the central hole of the head and having a central chamber, an annular channel on an outer surface thereof, which faces to the air inlet of the head, and at least one air hole defined through an underside of the annular channel and communicating with the central chamber; a fixing seat having a stub tube engaged with the central chamber of the cylindrical block, and an axially-extended through hole communicating with the central chamber; and an air delivery tube mounted to the fixing seat and communicating with the axially-extended through hole. Thus the air delivery tube can rotate relative to the head so as to allow the air pump to be operated at any angle.

Abstract: A diaphragm is provided in a pump case so as to define a pump chamber communicated with an external member having an air chamber. A motor actuates the diaphragm to introduce air into the pump chamber and to supply the introduced air to the air chamber. An exhaust valve exhausts air in the pump chamber to lower a pressure in the air chamber. The exhaust valve is provided with a valve body and an actuator which is driven by the motor to actuate the valve body so as to open or close an exhaust port communicated with the pump chamber.

Abstract: A liquid pump includes an electronically controlled throttle inlet valve to control pump output. With each reciprocation cycle, a plunger displaces a fixed volume of fluid. When less than this fixed volume is desired as the output from the pump, the electronically controlled throttle inlet valve throttles flow past a passive inlet check valve to reduce output. As a consequence, cavitation bubbles are generated during the intake stroke. Cavitation damage to surfaces that define the inlet port passage are avoided by a specifically shaped and sized cavitation flow adjuster extending from the valve member of the passive inlet check valve. By positioning the cavitation flow adjuster in the inlet port passage, a flow pattern is formed in a way to encourage cavitation bubble collapse away from surfaces that could result in unacceptable cavitation damage to the pump.

Abstract: A pump apparatus is provided which comprises a first displacement pump and a ceramic valve construction formed of a ceramic rotor, a ceramic stator having flat surfaces which are positioned in sealing relationship and a second displacement pump having check valves. The first displacement pump comprises a reciprocating first piston within a housing having an interior wall spaced apart from the piston. The position of the first piston and the position of the rotor are controlled to effect desired fluid flow through the stator. The first piston and a second piston of the second displacement pump are reciprocated by a common motor.

Abstract: A pump apparatus is provided which comprises a plurality of displacement pumps each connected to a check valve apparatus. The displacement pumps each comprises a reciprocating piston within a housing having an interior wall spaced apart from the piston. The check valve apparatus comprises two check valves that control fluid flow under pressure exerted by the reciprocating piston from a fluid reservoir to a point of use of the fluid. Pistons of the displacement pumps are driven by a common motor.

Abstract: In a reciprocating pump, drive power of a drive-power supply member is transmitted to a diaphragm within a diaphragm drive chamber via operating fluid. An operating-fluid-flow regulation chamber for regulating the flow of operating fluid is located between the drive-power supply member and the diaphragm drive chamber. A first gas discharge member and a second gas discharge member are respectively located in an upper part of the inside of the operating-fluid-flow regulation chamber and an upper part of the inside of the diaphragm drive chamber. The first gas discharge member is held in fluid communication with the second gas discharge member so as to constitute a single gas discharge mechanism. This single gas discharge mechanism is provided with a reverse-flow prevention member for preventing a reverse flow of fluid from the first gas discharge member to the second gas discharge member.

Abstract: A suction and discharge valve arrangement for a small hermetic compressor of the type presenting a compression cylinder (1), which has an end closed by a valve plate (10) and which has a suction pipe (5) adjacent to the valve plate (10) and substantially orthogonal to the cylinder axis, the valve plate (10) being provided with a discharge orifice (11) substantially centralized in relation to the axial projection (20) of the internal contour of the compression cylinder (1), and with at least one suction orifice (12), which is internal to said axial projection (20) of the internal contour of the compression cylinder (1), and defining at least part of the extension of a suction passage (P), with an end opened to the inside of the compression cylinder (1) and an opposite end opened and connected to the suction pipe (5) by means of a transition portion (T), which is configured to minimize load losses.

Abstract: A reciprocating compressor including cylinder block with a plurality of cylinder bores. A piston is positioned in each bore and mounted to move in response to the a crankshaft, causing each piston to reciprocate within the cylinder bore. The compressor further includes a cylinder head, which includes bores corresponding to the bores in the cylinder block, and a suction port in fluid communication with a source of compressible gas and a plurality of suction plenum. Protrusions or ribs extend into the suction plenum. The cylinder head also includes a discharge plenum in communication with the outlet ports of the valve plate. Interposed between the cylinder head and the cylinder block is a valve plate assembly having a discharge valve, and a discharge valve retainer having a pair of radii assembled to the valve plate by snap fitting a cylinder head gasket over the discharge valve and retainer.

Abstract: A compressor assembly including a compressor mechanism, a compression chamber and a discharge chamber. A discharge port provides fluid communication between the compression chamber and the discharge chamber. A valve seat circumscribes the discharge port. A discharge valve member having a valve head, a biasing section and a valve support is provided and may be formed out of a single integral part. The valve head is engageable with the valve seat. A non-threaded coupling member may mount the valve support to the cylinder block of the compressor mechanism. A guide member engageable with the biasing section of the valve member may also be provided. The valve head may include a second concave surface positioned opposite the surface engageable with the valve seat and have an effective area larger than the discharge port area. The valve head and valve seat may each be partially spherical surfaces having a common radius.

Abstract: A discharge valve mechanism has a plurality of discharge openings. The discharge openings are placed in an open or closed state by a plate-like valve element. Each of the discharge openings is formed at a respective location between a base end side and a leading end side of the valve element. The number of discharge openings to be placed in the open state is varied depending on the pressure and the flow rate of gas refrigerant discharged from a compression chamber.

Abstract: An improved structure of an air inflation device is disclosed. External air is drawn to the motor and cylinder to provide rapid cooling so that the efficiency of the motor is maintained. In the present invention, a plurality of air filters is used to filter air. Thereby the air inflation device is useful and practical.

Abstract: An exemplary system and method for manufacturing micropump systems having integrated piezoresistive sensors is disclosed as including inter alia: a substrate, an inlet channel, an outlet channel, a pumping cavity, a first valve for permitting fluid flow from the inlet channel to the pumping cavity and restricting backflow of purged fluid from the pumping cavity to the inlet channel; a second valve for permitting fluid flow from the pumping cavity to an outlet channel and restricting backflow of purged fluid from the outlet channel to the pumping cavity; a pump actuator element; a pressure sensing cavity surface capable of at least partial mechanical deformation; a plurality of piezoresistors disposed within the sensing cavity; a plurality of contact pads; a plurality of conductive pathways connecting the piezoresistors and the contact pads; and a substantially monolithic device package, wherein the sensing cavity is substantially contained within the micropump device package.

Abstract: A hand held an portable pump has a housing with an inlet on the bottom and an outlet on its side. A central tube extends up from the housing and has a bulb attached at its end. An inlet gate is positioned proximate the inlet to operate between a closed position in which the flow of liquid there through is inhibited and an open position in which liquid may flow through the inlet. The outlet has an outlet gate that is positioned to inhibit the flow of liquid into the housing in its closed position and to permit the flow of liquid out of the housing and into a discharge tube in the open position. The bulb is operated between an at rest position and a deflected or compressed position to urge fluid into and out of the bulb and in turn draw liquid through the inlet into the housing and to urge the liquid out of the outlet and into the discharge tube.

Abstract: A micropump has two chambers separated by an actuator for causing fluid to flow in the chambers. Each chamber is equipped with a ball that acts as a valve for allowing flow in a desired direction. The balls are heavier than the fluid being pumped, and reside at an interface between the chambers and passages feeding fluid into the chambers and provide a tight seal between the chambers and passages feeding the chambers when fluid pressure forces the fluid back toward the feeding passages.

Abstract: A compressor includes a compression chamber for compressing working fluid within an inside thereof, a discharge port, through which the working fluid flows out from the compression chamber, and a discharge valve for opening or closing the discharge port. The discharge valve includes a valve seat portion provided in the discharge port and having a tapered surface, so that a cross-section area of the discharge port comes to be large from a side of the compression chamber. The valve has a projection portion having a tapered surface in contact with the tapered surface of the valve seat portion. A spring is provided on a member formed in one body with the valve seat portion, for positioning the valve to the valve seat portion, wherein clearance volume of the discharge port is reduced, so as to improve the performances thereof.

Abstract: A compressor check valve having a valve bolt and a valve bolt cover for noise reduction and mitigation of impact from a valve bolt on the valve bolt cover. A bolt insertion hole is provided in the cover to receive the valve bolt. A pressure conduction hole penetrating from the side of the valve bolt insertion hole of the cover through the exterior of the cover is provided on the cover to connect the high pressure chamber through the valve bolt insertion hole. A buffer section is formed on a top of the valve bolt insertion hole so that the valve bolt is forced by a high pressure coolant to move above and block the pressure conduction hole, the buffer section contains high pressure coolant prevented from being discharged through the pressure conduction hole to create a buffer action when the valve bolt moves upward so as to avoid direct impact against the valve bolt cover.

Abstract: A piston pump for brake systems the region of the outlet valve is provided with a pressure chamber an opposing chamber, and a flexible wall that divides the pressure chamber from the opposing chamber. The flexible wall has an elastically resilient diaphragm that is supported in an elastically flexible body.

Abstract: A suction and discharge valve arrangement for a small hermetic compressor of the type presenting a compression cylinder (1), which has an end closed by a valve plate (10) and which has a suction pipe (5) adjacent to the valve plate (10) and substantially orthogonal to the cylinder axis, the valve plate (10) being provided with a discharge orifice (11) substantially centralized in relation to the axial projection (20) of the internal contour of the compression cylinder (1), and with at least one suction orifice (12), which is internal to said axial projection (20) of the internal contour of the compression cylinder (1), and defining at least part of the extension of a suction passage (P), with an end opened to the inside of the compression cylinder (1) and an opposite end opened and connected to the suction pipe (5) by means of a transition portion (T), which is configured to minimize load losses.

Abstract: The invention relates to a device for pumping a fluid into a bioreactor. Polsatile pumping is made possible by valve arrangement so that growth of the cells in the bioreactor is increased. Pumping function can be achieved though several mechanisms. A piston can be displaced in a cylinder, especially by an electromagnet, wherein a permanent magnet or likewise an electromagnet can be arranged in the piston. The piston can also be displaced by compressed air. An elastic, hollow body can also be provided, wherein said hollow body can be deformed by mechanical electromagnetic forces so that pumping function is achieved by a change in volume. The pumping device can also be used as implant for assisting or replacing heart function.

Abstract: The invention relates to a feed pump for delivering fluid media, wherein the pump bearings are lubricated by the feed medium itself. Connecting channels with valve devices are provided on the suction side and on the pressure side upstream and downstream, respectively, of a displacement element and link the bearing area of the pump with the production channel. Said connecting channels are configured as straight bores in the pump housing. The valve devices are configured as tappets that are disposed in the associated connecting channel sections so as to be displaced while being tight with respect to suction.

Abstract: A reciprocating piston compressor having a suction muffler and a pair of discharge mufflers to attenuate noise created by the primary pumping frequency in the primary pumping pulse. The suction muffler is disposed along a suction tube extending between the motor cap and the cylinder head of the compressor. The discharge mufflers are positioned in series within the compressor to receive discharge gases from the compression mechanism and are spaced one quarter of a wavelength from each other so as to sequentially diminish the problematic or noisy frequencies created during compressor operation. The motor/compressor assembly including the motor and compression mechanism is mounted to the interior surface of the compressor housing by spring mounts. These mounted are secured to the housing to define the position of the nodes and anti-nodes of the frequency created in the housing to reduce noise produced by natural frequencies during compressor operation.

Abstract: The present invention relates to microfluidic systems, including valves and pumps for microfluidic systems. The valves of the invention include check valves such as diaphragm valves and flap valves. Other valves of the invention include one-use valves. The pumps of the present invention include a reservoir and at least two check valves. The reservoir may be of variable volume. The present invention also relates to a flexible microfluidic system. The present invention additionally relates to a method of making microfluidic systems including those of the present invention. The method includes forming a microfluidic system on a master, connecting a support to the microfluidic system and removing the microfluidic system from the master. The support may remain connected to the microfluidic system or the microfluidic system may be transferred to another substrate. The present invention further relates to a method of manipulating a flow of a fluid in a microfluidic system.

Abstract: A vacuum pump non-return valve comprises a valve body that defines a through-passage having an inlet side and an outlet side. A valve seat is disposed intermediate said inlet and outlet sides of the through-passage. The valve seat is defined by an insert made of an elastomeric material. The non-return valve has a ball arranged to seat against the valve seat to prevent the passage of gaseous fluids from the outlet side to the inlet side. The ball is displaceable, in use, from valve seat by pressurised gaseous fluid in the inlet side of the through-passage to permit passage of gaseous fluid from the inlet side to the outlet side of the through-passage.

Abstract: A discharge valve assembly of fluid machinery is provided. The discharge valve assembly of fluid machinery includes a valve housing connected to a discharge side of a compression chamber, forming a valve holding space for holding a valve, forming a discharge hole on one side of the valve holding space, forming a back current hole in the other side of the valve holding space to be separated from the discharge hole, and fixedly installed in a discharge chamber, and a sliding valve positioned between the discharge side of the compression chamber and the discharge hole of the valve housing so as to open and close the discharge hole while sliding according to the pressure of the compression chamber and the pressure of the discharge chamber and inserted into the valve holding space to slide. The sliding valve completely opens the discharge side of the compression chamber and the discharge hole of the valve housing when compressed refrigerant gas is discharged.

Abstract: A cylinder head for reciprocating compressor comprises a frame including a insertion groove unit so as to make a concentric circle with a through hole penetrated in the body unit; a cylinder in which a cylinder body unit and a flange unit is coupled so as to be located at the through hole of the frame and the insertion groove unit respectively; a discharge cover in which the flange unit formed in the plenum unit is contacted on the step surface of the frame insertion groove; a plurality of volts connected to the step surface; and a valve body for switching the compressing space in the cylinder, thereby the assembling process of components can be simplified and productivity of the assembly can be increased by raising assembling accuracy.