820results about "Pulse equalisation" patented technology

A microfluidic device comprises pumps, valves, and fluid oscillation dampers. In a device employed for sorting, an entity is flowed by the pump along a flow channel through a detection region to a junction. Based upon an identity of the entity determined in the detection region, a waste or collection valve located on opposite branches of the flow channel at the junction are actuated, thereby routing the entity to either a waste pool or a collection pool. A damper structure may be located between the pump and the junction. The damper reduces the amplitude of oscillation pressure in the flow channel due to operation of the pump, thereby lessening oscillation in velocity of the entity during sorting process. The microfluidic device may be formed in a block of elastomer material, with thin membranes of the elastomer material deflectable into the flow channel to provide pump or valve functionality.

A pumping system including a plurality of pumps each having a pump fluid outlet, a drive shaft, a prime mover, and fluid displacing members operatively coupled with the drive shaft. A common fluid conduit may be fluidly coupled with each pump fluid outlet. A control system of the pumping system includes position sensors operable to generate information relating to phase and / or speed of each pump, pressure sensors operable to generate information relating to fluid pressure spikes, and a controller in communication with the position and pressure sensors. The controller is operable to cause the prime movers to adjust the phasing of the pumps with respect to each other, based on the information relating to fluid pressure spikes, and synchronize the speed of the pumps.

A pumping system including a plurality of pumps each having a pump fluid outlet, a drive shaft, a prime mover, and fluid displacing members operatively coupled with the drive shaft. A common fluid conduit may be fluidly coupled with each pump fluid outlet. A control system of the pumping system includes position sensors operable to generate information relating to phase and / or speed of each pump, pressure sensors operable to generate information relating to fluid pressure spikes, and a controller in communication with the position and pressure sensors. The controller is operable to cause the prime movers to adjust the phasing of the pumps with respect to each other, based on the information relating to fluid pressure spikes, and synchronize the speed of the pumps.

A fluid pump has a pump body and a displacer which is adapted to be positioned at a first and at a second end position by means of a drive, the displacer and the pump body being implemented such that a pump chamber is defined therebetween, and the pump chamber being adapted to be fluid-connected to an inlet and to an outlet via a first opening and a second opening which are not provided with check valves. An elastic buffer bordering on the pump chamber is provided. The displacer is implemented in the form of a plate which is secured to the pump body, and the pump body is provided with a recess defining the pump chamber. The drive acts on the displacer substantially in the area of the first opening. The displacer closes the first opening when it occupies its first end position and leaves the first opening free when it occupies its second end position. The drive means moves the displacer so abruptly from the second to the first end position that a deformation of the buffer means is caused by the movement of the displacer.

Operating a pumping system includes moving a pumping element to transition liquid through the pump, and determining a value based at least in part upon inlet pressure and pumping speed that is indicative of a pressure of the liquid within a bore susceptible to cavitation. Pumping speed and / or inlet pressure can be varied responsive to the determined value to limit cavitation.

The invention provides a pump for liquid chromatography excellent in feeding liquid stably at an extremely low flow rate and in discharging bubbles at startup. In a pump for liquid chromatography including a cylinder and a plunger that reciprocates in the cylinder to suck and discharge fluid, the pump further includes a large-flow-rate pump that feeds liquid by the plunger, a small-flow-rate pump that feeds the liquid by the plunger, motion conversion means that converts the rotational motion of a motor to a reciprocating motion, an actuator that directly drives the plunger, and a drive part that drives the actuator, and selectively switches means for driving the plunger.

A modular fluid end for a multiplex plunger pump, each module machined from a single-piece steel forging with a plunger bore intersected by a linear suction / discharge bore and pumped fluid is discharged straight out through a top of the module into a discharge manifold made up using 1502 frac iron components. A compression clamp applies a crush load to opposed sides of the modules to extend service life.

Easily detecting cavitation to occur in a pump. A detection apparatus, a detection method, and a program are provided. The detection apparatus includes: a discharge pressure acquiring unit to acquire discharge pressure data indicating discharge pressure of a pump; and a detector to detect occurrence of cavitation in the pump based on a fluctuation amount of a time waveform of the discharge pressure data during a target detection period. The detector may have: a fluctuation amount calculator to calculate the fluctuation amount of the discharge pressure data during the target detection period; and a determining unit to determine, in response to the calculated fluctuation amount becoming the reference fluctuation amount or more, that cavitation has occurred in the pump.

A fluid pressure pulsation damper mechanism comprising: a metal damper having two metal diaphragms joined together with a hermetic seal for forming a sealed spacing filled with a gas between the two metal diaphragms, an edge part at which are overlapped along outer peripheries thereof; a main body having a damper housing in which the metal damper is accommodated; and a cover attached to the main body to cover the damper housing and isolate the damper housing from an outside air, the metal damper being held between the cover and the main body; wherein the cover is further comprising: a metal plate for making the cover, a peripheral edge of the cover being joined to the main body, a plurality of inner convex curved parts extending toward the main body and a plurality of outer convex curved parts extending in a direction away from the main body, and a plurality of the inner convex curved parts and a plurality of the outer convex parts being disposed alternately inside the peripheral edge of the cover at which the cover is joined to the main body; wherein the cover is attached to the main body, ends of the plurality of inner convex curved parts touch one side of the edge part of the metal damper, which are outwardly formed in radial directions of a part including the sealed spacing in the metal damper; and the metal damper is held between the cover and a metal damper holding part of a holding member placed on the main body.

The invention relates to a vehicle hydraulic brake system with electrohydraulic brake boosting by a piston pump. In order to reduce pressure pulsations on an intake side of the multi-piston pump, the brake system embodies a multi-piston pump, for example, as a six-piston pump with stepped pistons that are driven with an alternating phase shift of 30° and 90° in relation to one another. The phase shift of the drive of the stepped pistons is selected so that the intake volume flows have a uniform phase shift, by which the total intake volume flow of the multi-piston pump has a reduced amplitude of the pressure pulsation, which reduces the repercussions on a master cylinder.

An invention is claimed that enables the pumping of compressible fluids at high pressures when an accurate flow is desired. Two pressure sources, for example pumps plumbed in series, separate thermodynamic work, such as pressurization, at the first pressure source from a volumetric or matter metering function in the second pressure source. One example is a flowstream delivery for a chemical instrumentation system that is manufactured from relatively unsophisticated pumps yet delivers precise flows with low pulsation (<1 %) over pressures greater than 100 bar. An advantage of one embodiment allows the economical conversion of typical HPLC systems to state of-the-art supercritical fluid chromatography (SFC) systems with minimal modification to system components.

The invention provides a pump for liquid chromatography excellent in feeding liquid stably at an extremely low flow rate with high accuracy and in discharging bubbles at startup.At startup, a first plunger feeds solvent at a large flow rate to discharge bubbles in a pump and to fill the solvent into the pump in a short time and in a normal operation, the first plunger is stopped and the second plunger is pushed into a second pressure chamber at a low speed to feed the solvent at a low flow rate. When the second plunger reaches full stroke, the second plunger is pulled back at a high speed and at the same time the first plunger is pushed into a first pressure chamber in synchronization with the pullback of the second plunger to control the flow rate passing a discharge passage to a constant value at all times by a controller. Further, while the second plunger feeds the solvent, the first plunger is slightly pushed into the first pressure chamber to keep pressure in the first pressure chamber at pressure equal to or less than pressure in the second pressure chamber.

A self-tightening retaining system for securing a closure in position closing an access port of a pump housing. The system includes a retaining cover for obstructing removal of the closure from a bore of the access port. The cover has external threads interengageable with screw threads of the bore. A locking device is configured for being secured to the cover such that the locking device rotates together with the cover. The locking device has a fastener receivable in a hole of the closure and has external threads interengageable with threads of the hole. The threads of the cover and the threads of the fastener are spiraled in opposite directions such that when the cover rotates in a loosening direction, the fastener becomes tightened in the hole of the closure thereby stopping the rotation.

The present invention is a means and method for providing constant output flow from a fluid pump. The invention does this by controlling the radial speed of the pump motor during discreet segments of the motor's 360° angular / radial path through a revolution of the pump. The electric pump motor is controlled throughout the 360° radial path by employing a control means for controlling the speed of actuation of the radial steps of a stepper motor throughout the 360° path of rotation of the stepper motor. Control means for controlling the speed of the discreet steps of the stepper motor comprises at least a memory means, a counting means and an amplification means.

To obtain a small and high performance damper mechanism which reduces pressure pulsation in low pressure-side fuel in the high pressure fuel pump in a high pressure fuel supply system or a high pressure fuel pump provided with the small and high performance damper mechanism.Two metal diaphragms are welded together over the entire circumference to obtain a metal diaphragm assembly (also referred to as “double metal diaphragm damper”). The whole or part of the portion of the metal diaphragm assembly other than the weld (for example, the portion inside the weld) is clamped by a pressing member and thereby the assembly is secured in a housing enclosure. The housing enclosure may be formed integrally with the body of a high pressure pump.

A dispenser for dispensing at two flow rates eductively draws a chemical fluid such as a concentrated cleaning solution for diluting with a motive fluid such as water. Using eduction rather than gravity feed provides a consistent dilution ratio over a range of pressures of the motive fluid. A chemical reservoir contains the chemical fluid and a bottle insert assembly for interfacing to the dispenser. The bottle insert assembly seals an opening to the reservoir when the reservoir is not inserted in the dispenser, preventing leaks. Also, the bottle insert assembly includes dual pickup tubes, each with a purge accumulator, to allow dual rate flow at the same or different dilution ratios as well as drawing back unused chemical fluids from the dispenser to avoid carryover or contamination.

The invention relates to a piston pump for a slip-controlled, hydraulic vehicle brake system. In order to be able to simply and inexpensively produce the piston pump as a stepped piston pump, the invention embodies a piston as a tubular deep drawn part made of sheet metal, with an outwardly protruding circumferential bead. The bead is produced by axially compressing the piston. The bead constitutes an axial support for a guide ring and sealing ring placed onto the piston. A disk-shaped, abrasion resistant striking piece is press-fitted into an open end of the tubular piston, and is used by the piston for resting against a circumference of a cam element used for the stroke drive.

A feedback control loop for a high pressure pump modifies the accumulator velocity and pressure during solvent transfer. The accumulator velocity is adjusted to maintain the system pressure equal to the expected pressure to thereby eliminate the effect of the flow deficit created by a thermal effect.

A pump includes: a pump chamber for which a capacity is changeable; an inlet channel which allows a working fluid to flow into the pump chamber; an inlet side fluid resistance element disposed between the pump chamber and the inlet channel; an outlet channel which allows the working fluid to flow out of the pump chamber; and a pipeline element formed inside the outlet channel, wherein a rotational flow generation structure, which generates a rotational flow of the working fluid, is provided in the pump chamber, and wherein the outlet channel is located adjacent to the rotational center of the rotational flow.

A simple structured high-pressure fuel pump.A fuel pump comprises a reciprocably-supported cylinder, a pressurizing chamber using part of the outer surface of the cylinder as the wall surface which move to change the internal volume, a fuel intake passage forming a fuel passage which introduces fuel to the pressurizing chamber, a fuel discharge passage for the compressed fuel coming out from the pressurizing chamber. A fuel intake valve is provided in fuel intake passage. A fuel discharge valve is provided in said fuel discharge passage. A connecting passage connects upstream side of the intake valve in the fuel intake passage and the downstream side of it. A check valve which flows fuel from the fuel discharge flow passage to the fuel intake passage is provided in the connecting passage.

A cylinder block assembly for a reciprocating pump includes a block body having a piston chamber that receives a piston of the reciprocating pump. The cylinder block assembly has an outlet valve assembly positioned within the block body that is positioned in fluid communication with the piston chamber. An outlet valve retainer retains the outlet valve relative to the piston chamber. The cylinder block assembly includes an inlet valve assembly extending through a side of the block body to the piston chamber. An inlet valve retainer also retains the inlet valve assembly relative to the piston chamber. A discharge passage extends from the outlet valve assembly to another side of the block body. A portion of the discharge passage extends between the inlet valve assembly and the inlet valve retainer.

The invention relates to a piston pump with a piston received axially displaceably in a pump bore. To improve the aspiration performance of the piston pump. A cuff with a U-shaped annular cross section is provided, the cuff is inserted into the pump bore surrounding the piston, an outer lip forms a diaphragm, which rests against a wall of the pump bore and is acted upon on its outside with ambient pressure through a venting bore. The cuff is part of a fluid storage element, which makes an additional fluid volume available to the piston pump. The diaphragm acted upon by ambient pressure creates a pumping effect, if a fluid pressure in the fluid storage element drops below ambient pressure in an intake stroke of the piston.

Disclosed is a pump unit of an electronic control brake system installed in a bore formed in a modulator block, the pump unit including a motor having a rotating shaft, a carrier having a center portion thereof installed on the rotating shaft, and provided with connecting shafts that are spaced apart from the center portion to both sides by a predetermined interval to be disposed in line with each other, a pressing member installed on each of the connecting shafts, and a first piston pump and a second piston pump each provided with a piston configured to be reciprocated by making contact with an outer circumferential surface of the pressing member according to rotation of the carrier, the first piston pump and the second piston pump disposed in line with each other.

The invention relates to a piston pump, which is intended for use as a return pump for a slip-controlled hydraulic vehicle brake system. To simplify the manufacture of a piston of the piston pump, the piston includes a thin sleeve.

A fuel feed system capable of feeding a fuel to fuel injection valves at a fuel pressure with improved stability is provided. A fuel feed system for an internal combustion engine including a fuel tank and a low-pressure pump for feeding the fuel in the fuel tank to fuel injection valves, is provided with a diaphragm type damper having a wave-shape cross section at a position in contact with the fuel. Also, in a high-pressure fuel feed pump including a pressurizing chamber for pressurizing the fuel, a plunger for pumping the fuel within the pressurizing chamber, an intake valve provided at a fuel inlet of the pressurizing chamber, a discharge valve provided at a fuel outlet of the pressurizing chamber, and a low-pressure chamber provided in an upstream of the intake valve, a mechanism for reducing fuel pressure pulsation is disposed in a space of the low-pressure chamber provided in the upstream of the intake valve, and a fuel pressure sensor for measuring the fuel pressure is mounted near the mechanism for reducing fuel pressure pulsation.

To obtain a small and high performance damper mechanism which reduces pressure pulsation in low pressure-side fuel in the high pressure fuel pump in a high pressure fuel supply system or a high pressure fuel pump provided with the small and high performance damper mechanism. Two metal diaphragms are welded together over the entire circumference to obtain a metal diaphragm assembly (also referred to as “double metal diaphragm damper”). The whole or part of the portion of the metal diaphragm assembly other than the weld (for example, the portion inside the weld) is clamped by a pressing member and thereby the assembly is secured in a housing enclosure. The housing enclosure may be formed integrally with the body of a high pressure pump.

Hermetic compressor including a hermetic container having an enclosed space therein, a motor part in the hermetic container for converting an electric energy into a kinetic energy, a compression part connected to the motor part for compressing low temperature, low pressure refrigerant into high temperature, high pressure refrigerant, a discharge muffler adjacent to the compression part for attenuating noise of the refrigerant compressed into high temperature and high pressure, a discharge pipe passed through one side of the hermetic container for discharging the refrigerant to an outside of the compressor, and a loop pie of a synthetic resin between the discharge muffler and the discharge pipe.

In piston pumps for brake systems used until now, there were often noise problems, from pressure pulsations. In the piston pump for brake systems proposed here, a pulsation-smoothing device (40) that functions effectively well is provided in the region of the outlet valve (24). As a result, substantially less noise occurs, and the durability of the piston pump (1) is substantially better. The piston pump is used essentially in traction-controlled motor vehicle brake systems.

A fuel pump includes a housing having therein a suction passage and a pressurization chamber into which fuel from the suction passage flows, a plunger held in the housing to be reciprocable so as to pressurize the fuel flowing into the pressurization chamber, and a diaphragm device located in a suction chamber that is provided in the suction passage. The diaphragm device includes a pair of first and second diaphragms that are arranged to define an inner space therebetween and air-tightly sealed at its entire peripheries. A mass addition member may be attached to an inside surface of at least one of the first and second diaphragms, so that the first and second diaphragms with the mass addition member have different characteristic frequencies. Accordingly, pressure pulsation of the fuel in the suction chamber can be effectively reduced by the pulsation damper.