Abstract: A valve arrangement structure of a control valve unit includes a control valve body to which oil is supplied from a main pump. The valve arrangement structure includes a pressure regulator valve that is arranged in the control valve body and regulates a pressure of discharged oil from the main pump to a line pressure, a pressure control valve that is arranged in the control valve body and regulates the pressure of the oil to a required pressure with the line pressure as a source pressure, and a first oil passage that is provided in the control valve body and connects the main pump and the pressure regulator valve. The pressure control valve is arranged on a second oil passage branched from the first oil passage.

Abstract: Provided is an oil feed type air compressor which can increase the determination accuracy regarding a deterioration state of oil. An oil feed type air compressor 1 includes a compressor main body 3, a separator 6 that separates oil from compressed air discharged from the compressor main body 3, and an oil feeding system 8 that feeds the oil separated by the separator 6 into a compression chamber of the compressor main body 3. The oil feeding system 8 includes a temperature control valve 20 that adjusts a diversion ratio for an oil cooler 18 and a diversion ratio for a bypass pipe 19 according to a temperature of the oil.

Abstract: A compact, modular dosing pump system that is capable of microdose and macrodose volume flow rates, reduces or eliminates the need for additional flow control components such as temperature and pressure sensors, and utilizes a wider operational flow range than existing systems while maintaining the level of accuracy and precision exhibited by conventional dosing pump systems is provided. The dosing pump utilizes a a control system to deliver a range of fluid volumes. The control system monitors the motor emf voltage, calculates the flow rate, and makes adjustments to the pump motor voltage to precisely maintain the desired flowrate.

Abstract: An inter-stage coupling for a multi-stage vacuum booster pump may include a first coupling face configured to be received by a first adjacent stage of the multi-stage vacuum pump; a second coupling face configured to be received by a second adjacent stage of the multi-stage vacuum pump; and a recirculator comprising a recirculation inlet aperture formed in the first coupling face, a recirculation outlet aperture formed in the first coupling face, and a recirculation conduit having a recirculation valve configured to selectively fluidly couple the recirculation inlet aperture with the recirculation outlet aperture. In this way, the pressure in a stage can be relieved by fluidly coupling the outlet aperture with the inlet aperture in order to recirculate built-up gas from one part of the first stage pump to another part of the first stage pump in order to reduce the strain on the rotor.

Abstract: What is concerned is an eccentric screw pump having at least one stator (1), a rotor (2) rotating in the stator, a drive (3) for the rotor, a pump housing (4) which is connected to the stator (1) and has at least one inlet opening (6) for the medium to be conveyed, a connection housing (14) arranged between the pump housing (4) and drive (3), a connection shaft (9) which is connected to the drive (3) and is arranged at least in certain regions in the connection housing (14), and a coupling rod (10) which is arranged in the pump housing (4) and is connected to the connection shaft (9) via a drive-side joint (11) and to the rotor (2) via a rotor-side joint (12). The drive-side housing connection piece (16) can be demounted in such a way that the drive-side joint (11) can be exposed for maintenance or demounting.

Abstract: A compressor may include a shell assembly, first and second scrolls, and a valve assembly. The shell assembly may define a discharge chamber. The first scroll may be disposed within the discharge chamber and may include a first end plate and a first spiral wrap. The first end plate may include a discharge passage in communication with the discharge chamber. The second scroll may be disposed within the discharge chamber and may include a second end plate and a second spiral wrap. The first and second spiral wraps define fluid pockets therebetween. The second end plate may include a port selectively communicating with one of the fluid pockets. The valve assembly may be mounted to the second scroll and may include a valve member that is movable between open and closed positions to allow and restrict communication between the port and the discharge chamber.

Abstract: Systems, methods, and devices are described for providing a brace having an inflation control. The control directs fluid flow from an inflation component to one or more inflatable cells of the brace. The inflatable cells are independently inflated and deflated by the inflation component through the control. The control allows a user to create a fluid path between the inflation component and one of the inflatable cells by positioning the control in an orientation corresponding to the desired inflatable cells. Each inflatable cell is independently inflated and deflated in various orientations of the control.

Abstract: Techniques are provided for protecting a twin screw positive displacement pump, that include a signal processor that receives signaling containing information about power, torque, speed, viscosity and specific gravity related to the operation of the twin screw positive displacement pump; and determines whether to enter an enhanced pump protection mode for the twin screw positive displacement pump based on a relationship between an actual corrected tune ratio and a tuned ratio set point (Tune Ratio SP). In operation, the signal processor determines if the actual corrected tune ratio is<=the actual corrected tune ratio set point (Tune Ratio SP), and if so, then enters the enhanced pump protection mode, else continues to use a basic pump protection mode, and also determines the actual corrected tune ratio based on a ratio of an actual corrected torque (TAcorr) divided by a tuned corrected torque (TTcorr) at a specific operating speed.

Abstract: A center section/motor sub-assembly for use in a hydrostatic transmission includes a center section having a pump running face for interfacing with a pump, and a motor running face for interfacing with a motor. The center section and the motor are configured for the hydraulic separating forces of the motor to be reacted only into the center section. The center section has two internal passages between pump kidney ports and motor kidney port, and the motor kidney ports are raised in elevation relative to the pump kidney ports. The internal passages run parallel to each other as they rise in elevation. A hydrostatic transmission includes the sub-assembly enclosed by a housing, in combination with a pump and output shaft assembly. For installation, the output shaft assembly is configured as a separate component from the sub-assembly of the center section and the motor.

Abstract: A slide valve forming a part of a bore and movable in an axial direction of the rotors, foot sections on a discharge side end face of the slide valve, and discharge ports and on a discharge chamber side of the slide valve in order to discharge compressed gas taken into a compression operation chamber from the suction chamber and compressed. At a discharge side end portion of the slide valve, first discharge channels and lead the compressed gas discharged from the discharge port and lead the compressed gas to the discharge chamber and second discharge channels are provided on a radial direction outer side of the first discharge channel and opened to the first discharge channels and the discharge chamber to lead a part of the compressed gas flowing in the first discharge channels and feed the part of the compressed gas to the discharge chamber.

Abstract: An air pump includes a barrel and a pumping device moving with respect to the barrel when the air pump is operated. A joint assembly fluidly connecting to the air pump is disposed on the barrel and includes a first hole to receive air from the air pump, a connecting device including a rotatable adaptor, and a second hole extending through the rotatable adaptor and fluidly connecting to the first hole. A pressure gauge connects to the joint assembly on the rotatable adaptor, includes an air inlet hole fluidly connecting to the second hole, has a first side thereof including a first dial with a first measuring range and a second side thereof including a second dial with a second measuring range different from the first measuring range, and is rotatable between use positions thereof.

Abstract: A lubricant vane pump for providing a pressurized lubricant for an internal combustion engine includes a pump housing, a pump chamber, a shiftable control ring comprising a pressure-relief-valve, a pump rotor, a pretensioning element which pushes the control ring into a high pumping volume position, a control chamber, and a pump outlet cavity fluidically connected to the control chamber. The pump chamber comprises pump compartments which rotate from a charge to discharge zone. The control ring envelops the pump chamber. The pump rotor comprises radially slidable vanes which rotate in the control ring to provide the pump chamber with the pump compartments. A high lubricant pressure in the control chamber moves the control ring into a low pumping volume direction against the pretensioning element. The pressure-relief-valve of the control ring connects or disconnects the control chamber with one of the pump compartments between the charge zone and the discharge zone.

Abstract: A stator for eccentric screw pumps with a stator casing for an elastomer body for accommodating a rotor, the elastomer body being provided with at least one collar, wherein the collar is disposed in a recess between the stator casing and a connection body, wherein the fixing of the elastomer body in the stator casing is to be improved. The stator casing includes for this purpose open cavities, recesses and/or elevations at least at one side on the end face.

Abstract: An upper back pressure type scroll compressor is provided having a back pressure chamber. The scroll compressor may include a casing, a discharge cover, a main frame, a first scroll supported by the main frame, and a second scroll forming a suction chamber, an intermediate pressure chamber, and a discharge chamber together with the first scroll. The scroll compressor may also include a back pressure plate coupled to the second scroll. The back pressure plate may include a cavity with which the intermediate pressure chamber of the second scroll communicates. The scroll compressor may further include a floating plate movably coupled to the back pressure plate so as to seal an upper portion of the cavity.

Abstract: A system for monitoring wear of pump casing liners is disclosed. The system may include a wear sensor disposed in proximity to the pump casing liner so that the sensor wears at substantially the same rate as the lining. The wear sensor may include a plurality of circuit loops having different lengths. As the pump casing liner and the sensor wear during use, the plurality of circuit loops are sequentially breached. A control system monitors the signals from the plurality of circuit loops to develop liner wear information. This information is employed to signal a user when one or more predetermined wear thresholds are exceeded.

Abstract: A scroll compressor having a back pressure discharge is provided. The scroll compressor may include a casing, a discharge cover, a main frame, a first scroll supported by the main frame, and a second scroll forming at least a discharge chamber together with the first scroll. The second scroll may include a discharge opening through which an operation fluid may be discharged. The scroll compressor may also include a back pressure chamber assembly fastened to the second scroll with a Efastener, a back pressure discharge opening that communicates with the back pressure chamber, and a discharge path by which the discharge chamber and the discharge space communicate with each other. The scroll compressor may further include a check valve disposed at the back pressure discharge opening to prevent the operation fluid from being introduced into the back pressure chamber.

Abstract: A scroll compressor is provided. The scroll compressor may include a valve and a valve spring accommodated in a housing as one module, and the housing may be directly coupled to a fixed scroll. This may simplify assembly processes of the scroll compressor. Further, a sealing recess that communicates with a middle pressure chamber may be formed at the housing, thereby forming a damping space between a high pressure space and a low pressure space. This may prevent lowering of performance of the scroll compressor due to leakage of refrigerant inside the high pressure space to the low pressure space in a normal driving mode.

Abstract: A shoe, such as an athletic shoe, includes a pump assembly integral therewith. The pump assembly includes a pump which produces a stream of pressurized air and a delivery assembly which operates to deliver the stream of pressurized air to an end use location exterior of the shoe. The shoe may comprise an athletic shoe and may be utilized to inflate sports balls such as basketballs, footballs, and volleyballs.

Abstract: A bypass valve (1), in particular a compressor bypass valve, having a valve housing (2); a valve guide body (3), which is fixed in the valve housing (2); and a valve disk (4), which is guided between a closed position and an open position by the valve guide body (3) in the valve housing (2). The the valve guide body (3) and the valve disk (4) are in the form of plastic parts.

Abstract: A screw compressor includes a casing and a compression mechanism accommodated in the casing. The compression mechanism has a screw rotor, a gate rotor and a communication mechanism. The gate rotor has a flat plate shape. A rotational axis of gate rotor is orthogonal to a rotational axis of the screw rotor. The communication mechanism is arranged to communicate a high pressure space and a low pressure space in the casing.

Abstract: A compressed air supply installation for operating a pneumatic installation, especially an air suspension installation of a vehicle, includes an air supply unit and an air compression unit for supplying a compressed air supply unit with compressed air, a pneumatic connection, especially a bleeding line, comprising a bleeding valve and a bleeding port for bleeding air, and a pneumatic connection, especially a compressed air supply line having an air drier and a compressed air port for supplying the pneumatic installation with compressed air. The air drier has a drier container through which compressed air can flow and which contains a desiccant. The drier container has a wall forming a desiccant-free recess, and at least part of the bleeding valve system is arranged in the recess.

Abstract: A reciprocating cryogenic pump 2 comprises a piston reciprocable within a pumping chamber 44. The pumping chamber 44 has an inlet suction valve 48 for cryogenic liquid to be pumped and an outlet 32 for high pressure cryogenic liquid. The inlet valve 48 for the cryogenic liquid communicates with a cryogenic liquid reception chamber 46 in the cold end or head 6 of the pump 2. The pump head 6 is at least partially surrounded by a first jacket 8 retaining primary vacuum insulation. The first jacket 8 is itself at least partly surrounded by a second jacket 10. The jacket 10 defines a chamber for the reception of a coolant fluid such as liquid nitrogen and the second jacket has an inlet 20 and an outlet 22 for the liquid nitrogen. The thermal insulation can be further enhanced by a trapped gas space 73 between the first jacket 8 and an inner sleeve 52, the latter defining with an outer sleeve 50 vacuum insulation for the pumping chamber 44.

Abstract: The invention discloses an adaptor (10,50) for an air compressor (11,51). Adaptor (10,50) includes a manifold (14,52) having an inlet (20,74) adapted to be connected to the air exhaust of at least one air tool device (34) having an air motor connected, in use, to the air compressor (11, 51). An outlet (12,54) is adapted to be connected, in use, to the air intake of the air compressor (11,51), an air inlet (16,70) is open to ambient air and a valve mechanism (33,66) is adapted to, in use, close the air inlet (16,70) when a first predetermined pressure is reached by the air compressor (11,51).

Abstract: A compressor includes a housing; a suction region and a discharge region which are formed in the housing in a partitioned manner. The compressor also includes a shaft which is pivotally supported in the inside of the housing. The compressor further includes a compression mechanism which sucks a refrigerant from the suction region and discharges the refrigerant to the discharge region due to a rotational motion of the shaft. The compressor further includes a bypass passage which makes the suction region and the discharge region communicate with each other, a valve element 41 which is capable of closing the bypass passage 40 from a discharge region side, and a spring which biases the valve element toward the discharge region side.

Abstract: In an oil pump for an automatic transmission, a suction port is adapted to be connected to a first suction passage. The first suction passage is arranged in parallel with a second suction passage connected to an auxiliary pump. The first and second suction passages branch from an upstream suction passage leading to an oil strainer. A discharge outlet is adapted to be connected to a first discharge passage. An air vent hole is disposed downstream of the suction port and upstream of the discharge outlet. A communication passage is connected to the air vent hole and adapted to reach a predetermined oil level in an oil pan so as to communicate the air vent hole with inside of oil in the oil pan.

Abstract: In general, a piston-type pump includes a wash flow path that allows a wash liquid such as water to pass through to provide washing and cleaning as the pump operates. The pump may be used in precision liquid dispensing systems and particularly with liquid solutions that have a tendency to precipitate solid particulate. By washing a portion of the pump piston, the liquid solution being dispensed and any solid particulates may be carried away and removed from the pump.

Abstract: A variable oil pump capable of rapidly ejecting a required amount of working fluid using an oil pressure of the working fluid generated according to an engine RPM, and improving a lubrication effect to improve engine efficiency. Also described is a variable oil pump, in which a gap is provided between a plunger and a cylinder to easily operate the plunger using an oil pressure output from an oil pump, enabling more rapid supply of a required amount of oil using an oil pressure varied according to variation in an engine RPM. A variable oil pump is described in which the plunger is perpendicularly operated with respect to a flow direction of the working fluid, such that the plunger can be operated in a direction in which a pressure of the working fluid is applied to operate the oil pump.

Abstract: A pneumatic inflation device disposed within the sole of a shoe and comprising a pump with integral air release valve and which is entirely within the sole, a pump actuator which is entirely within the sole when not in use, and an inflatable bladder which is entirely within the sole and is operatively connected to the pump. Such a device can include a mechanism to lock the pump actuator within the sole such that the mechanism's cap is flush with the outer wall of the sole and finger-operable to allow the shoe-wearer to easily operate the inflation device and release air therefrom.

Abstract: A compressor includes a housing, a first scroll member, a second scroll member and a valve assembly. The first scroll member is positioned within the housing and includes a first end plate portion and a second end plate portion coupled to the first end plate portion and having a first spiral wrap extending therefrom. The first end plate portion and the second end plate portion define a discharge passage. The second scroll member is positioned within the housing and includes a second spiral wrap meshingly engaged with the first spiral wrap. The valve assembly is supported by at least one of the first end plate portion and the second end plate portion at a location radially outward from the discharge passage.

Abstract: A diaphragm pump for a seat adjusting device comprises a diaphragm and a valve member which define a pump chamber therebetween. An inlet valve and an outlet valve are formed on the valve member. A pressure chamber is in fluid communication with the outlet valve and receives fluid discharged from the pump chamber via the outlet valve. One of the diaphragm and the valve member comprises a valve membrane of a pressure relief valve integrated in the pump. The valve membrane is integrally formed with the one of the diaphragm and the valve member. The valve membrane is moveable between a first configuration in which the valve membrane closes a pressure relief channel and a second configuration in which the valve membrane opens the pressure relief channel to allow fluid to be discharged from the pressure chamber.

Abstract: A diaphragm metering pump includes a pump body having a head portion including a suction side and a discharge side defining a flow path. A valve seat is arranged at one of the suction side and the discharge side, and a check valve is arranged at the valve seat. A degassing system includes a check valve actuator operatively connected to the check valve. The check valve actuator is selectively activated to unseat the check valve from the valve seat to allow gases trapped in the head portion to pass through the discharge side.

Abstract: A combined debris catcher and pressure relief valve positionable between first and second ports of an inlet arrangement that is upstream of the main body of a vacuum pump. The debris catcher includes an open ended tube that is spring biased upwardly and in normal operation forms a seal with the inlet arrangement. In the raised or sealed position, incoming fluid from the system to be evacuated travels along a closed flow path through the first port of the inlet arrangement, through the debris catcher, and out through the second port of the inlet arrangement into the main body of the vacuum pump. If the inlet arrangement is hooked up initially or at any time to a system that is above atmospheric pressure, the above atmospheric pressure will overcome the upward force of the spring on the tube and cause the tube to move to an open position spaced from the inlet arrangement harmlessly venting the high pressure fluid to ambient air and avoiding potential damage or contamination to the pump.

Abstract: Disclosed is a hydraulic circuit for controlling booms of construction equipment, wherein working oil which is relieved from a large chamber of a boom cylinder passes through an orifice so as to prevent the boom from lowering if an overload is applied when the boom is not being operated.

Abstract: A screw compressor includes a pair of rotors housed in a rotor chamber. A gas sucked from an intake channel is compressed by the screw rotors and discharged from a discharge channel. A columnar space having a functional end face with an opening into an intermediate pressure section, which is an empty space in the rotor chamber and isolatable from both the intake channel and the discharge channel by the screw rotors. The functional end face has an opening into a bypass channel in communication with the discharge channel. A piston, inserted in the columnar space and brought into contact with the functional end face, separates the intermediate pressure section from the bypass channel when the piston contacts the functional end face. A pressure detection channel allows an area located on an opposite side of the functional end face in the columnar space to communicate with the discharge channel.

Abstract: A high-performance oil pump for pumping oil in an internal combustion engine that eliminates or greatly reduces cavitation in the oil pump, thereby increasing the efficiency and performance of the oil pump. The present invention provides a housing having an inlet for receiving a supply of oil and an outlet for discharging the oil. At least two gears rotatably and matingly are disposed within the housing for pumping the oil from the inlet to the outlet. A pressure regulation circuit is disposed within the housing for balancing oil flow pressure between the inlet and the outlet by redirecting a portion of the oil from the outlet to the inlet when said oil flow pressure reaches a predetermined level at the outlet in order to reduce or eliminate cavitation of oil in the oil pump.

Abstract: A hydraulic control system for preventing shortage of lubricant and coolant during charging of an accumulator is disclosed. The hydraulic control system is comprised of: a hydraulic pump; an accumulator for storing fluid from the pump; and a constant delivery site which is connected to the pump in parallel with the accumulator, and which requires hydraulic fluid constantly during activation of the hydraulic pump. A pressure level of the fluid discharged from the pump is regulated to a level possible to be delivered to the accumulator, and the fluid resulting from the pressure regulation is delivered to the constant delivery site. Meanwhile, a pressure higher than that required by the constant delivery site is stored in the accumulator. The hydraulic control system is characterized by a fluid increasing means that delivers additional fluid to the constant delivery site together with the fluid resulting from said pressure regulation, when delivering the fluid discharged from the pump to the accumulator.

Abstract: A compressor includes a shell assembly, first and second scroll members and a capacity modulation assembly. The first and second scroll members form a series of pockets. A first modulation port defined in the first scroll member is in communication with a first pocket. The capacity modulation assembly is in communication with the first modulation port and is operable in full, partial and first and second pulse width modulation (PWM) capacity modes. The full capacity mode includes the first modulation port isolated from a suction pressure region of the compressor, the partial capacity mode includes the first modulation port in communication with the suction pressure region, the first PWM capacity mode includes a capacity between full and partial capacity via PWM between the full and partial capacity modes and the second PWM capacity mode includes a capacity between full and zero capacity by providing PWM of the capacity modulation assembly.

Abstract: The invention relates to the oil-producing industry and can be used for extracting oil with a large content of gas in the liquid being pumped out. The well-drilling sucker-rod pump comprises a cylinder containing a hollow plunger, in the lower part of which a delivery valve is mounted. An inlet valve is mounted in the lower part of a pump chamber. The pump is equipped with a passageway having a floating valve which has a cut-off floating element and a seat arranged above the latter. The cylinder is stepped on the internal surface side, and the passageway having the cut-off floating element is formed in the lower part of a smaller cylinder step above the pump chamber. One passageway opening is connected to the upper part of the pump chamber and the other passageway opening is connected to the well. As a result, the pump efficiency is increased and gas generation in the pump chamber is reduced.

Abstract: A variable capacity type rotary compressor, in which a refrigerant sucked in via one suction pipe can be alternately sucked into each compression space via a communication passage between cylinders so as to reduce a number of components and a number of assembly processes, thereby reducing fabrication costs. A refrigerant within an idling cylinder is prevented from flowing back into another cylinder so as to improve performance of the compressor. A welding space can be ensured when connecting connection pipes so as to realize a welding automation, thereby further reducing the fabrication cost, and a mode switching valve is stably fixed to an appropriate position so as to attenuate noise due to vibration of compressor.

Abstract: A rotary compressor is provided, in which an inner diameter of a connection hole connected to a vane chamber and an outer diameter of a connection tube inserted into the connection hole are designated so that the connection tube can closely be adhered to the connection hole, thereby preventing a refrigerant from being leaked out between the connection hole and the connection tube so as to allow a fast and accurate mode switching of the vane, resulting in improvement of the performance of the compressor and prevention of noise caused by vibration of the vane.

Abstract: An apparatus is provided and may include a compression mechanism, a valve plate having a plurality of ports, a header, and a plurality of cylinders disposed within the header. A plurality of pistons may be respectively disposed in the plurality of cylinders and may be movable between a first position separated from the valve plate and permitting flow through the plurality of ports and into the compression mechanism and a second position engaging the valve plate and restricting flow through the plurality of ports and into the compression mechanism. A chamber may be disposed within each of the cylinders and may receive a pressurized fluid in a first mode to move the piston into the second position and may vent the pressurized fluid in a second mode to move the piston into the first position. One of the chambers may include a different diameter than the other of the chambers.

Abstract: A compressor safety valve releases an abnormal pressure to the outside through a discharge port when the pressure in a compressor has increased abnormally. The valve comprises a cap having an anchoring part integrally formed therewith and mounted on a head portion of a valve main body in an attachable and detachable manner. The valve further comprising an elastic body interposingly mounted between the cap and the head portion of the valve main body in a compressed state and in close contact with the head portion of the valve main body. The elastic body is interposed so as to cover the entirety of a peripheral surface of the discharge port and the cap is anchored to the head portion of the valve main body by the elastic repulsive force of the elastic body, so that the discharge port is closed by the elastic body and the cap.

Abstract: A control method and apparatus for critical rotational speed avoidance in a compressor-expander set in a gas refrigeration system. By varying an opening of an antisurge or recycle valve, a shaft power used by the compressor in the compressor-expander set may be varied, thereby varying the rotational speed of the compressor-expander set to move it away from its critical speed zone. Additionally, a feedforward signal may be provided by a compressor-expander set control system to cause an antisurge valve for a recycle compressor to open upon a trip or shutdown of one compressor-expander set.

Abstract: A fuel injection pump is provided which can be manufactured without an increase in the manufacturing cost and which is configured so that the sealing performance of an electromagnetic spill valve can be maintained with minimum maintenance cost.

Abstract: The invention relates to an air conditioning compressor (1) for a vehicle (24), in particular a motor vehicle (25), having a compression chamber (18) having an inlet (7) for a cooling medium to be compressed and an outlet (8) for the compressed cooling medium, wherein a wall of the compression chamber (18) is formed at least in sections by a translationally displaceable piston (3). According to the invention, the end of the piston (3) facing away from the compression chamber forms at least one wall region of a control pressure chamber (19). The invention further relates to a vehicle having an air conditioning apparatus.

Abstract: A pump includes a shell, an air-pumping device, a cover, a valve and a buoyant. The air-pumping device is used for pumping air out of the shell and therefore pumping liquid into the shell. The cover includes an opening and channel defined therein. The cover is attached to the shell and the air-pumping device. The shell is in communication with the exterior thereof via the opening. The shell is in communication with the air-pumping device via the channel. The valve is movable between a first position for releasing the channel and a second position for blocking the channel. The valve is in the second position as the pump is in an inverted position. The buoyant is used for moving the valve to the second position as the pump is almost full of liquid in an upright position.

Abstract: A diaphragm metering pump suitable for metering an effervescent gas. The pump has a pump head with a product chamber having an inlet end with a one-way inlet valve and an outlet end with a one-way outlet valve. A displaceable diaphragm member defines a boundary of the product chamber. The diaphragm member is capable of being reciprocated to cause pumping displacements. A discharge side is disposed downstream from the outlet valve. A passageway is disposed in fluid communication between the discharge side and the product chamber. A valve is disposed in the passageway. The valve is opened intermittently to allow liquid to re-enter the product chamber in an amount effective to purge gas from the product chamber to prevent loss of prime.

Abstract: A multi-cylinder dry-running piston compressor for generating compressed air. The piston compressor includes a crankcase having an interior and a crankshaft rotatably mounted in the crankcase. Also included are two connecting rods mounted in the crankshaft and configured to run counter to one another. Further included are two cylinders mounted in the crankcase and a piston arranged at an end of each of the connecting rods and configured to run in a respective one of the two cylinders.

Abstract: A compressor piston including a piston in a cylinder; a connecting rod connecting the piston to a crankshaft in a crankcase by a roller bearing; and an air inlet line and an air outlet line in a cylinder head. A tube connection between the air inlet line and the crankcase transports cooling air from the inlet line to the crankcase. The tube connection is exterior the cylinder. An inlet valve is connected to the tube connection which opens when the pressure in the crankcase is less than the pressure in the air inlet line; and an outlet valve is connected to the crankcase which opens when the pressure in the crankcase exceeds a predetermined value.

Abstract: An apparatus is provided and may include a compression mechanism, a valve plate including a plurality of ports in fluid communication with the compression mechanism, and a header disposed adjacent to the valve plate. A plurality of cylinders may be disposed within the header and a plurality of pistons may be respectively disposed in the plurality of cylinders and may be movable between a first position separated from the valve plate and a second position engaging the valve plate. A chamber may be disposed within each of the cylinders and may receive a pressurized fluid in a first mode to move the piston into the second position and may vent the pressurized fluid in a second mode to move the piston into the first position. One of the chambers may include a smaller volume than the other of the chambers.