Patent application number | Description | Published |
20100065495 | APPARATUS AND METHODS FOR PREPARATIVE LIQUID CHROMATOGRAPHY - A method of liquid chromatography includes providing one or more solvent reservoirs, providing a solvent pump, drawing one or more solvents into the pump in response to a pressure drop that promotes outgassing of the solvents, and dispersing outgassed bubbles into smaller bubbles to promote re-dissolution of the gas. A liquid-chromatography apparatus includes at least two solvent reservoirs, a pump, at least one bubble-dispersing unit that receives a pressurized flow of proportioned solvents from the pump, and a control unit. The control unit includes a processor and a memory that stores instructions; the control unit controls proportioning of solvents to obtain a preselected solvent composition, and pumping at flow rates to support preparative-scale or process-scale liquid chromatography. | 03-18-2010 |
20110261642 | Valve Switch Modulation For Reducing Errors Due Oscillations Of The Inlet Fluid Of A Pump System - Described is a method of reducing liquid composition errors in a low-pressure mixing pump system. Packets representing the switching intervals of each component of the desired fluid mixture are provided to an intake of the mixing pump system. For each packet, a switching time associated with at least one of the components in the packet is modulated. Modulated switching times are based on time offsets that are specifically selected according to the undesirable frequency characteristic of an intake response of the mixing pump system. The average of the volumes contributed by the packets thus modulated is equal to a component volume that achieves a desired proportion of the component in the output flow of the mixing pump system. Modulated switching times enable the reduction or elimination of composition error in the output flow of the mixing pump system. | 10-27-2011 |
20120032628 | Intake Profile For Optimized Utilization Of Motor Characteristics - Systems and methods for operating a stepper motor of a pump at a desired low velocity include memory for storing information corresponding to an intake velocity profile. The intake velocity profile represents an optimized acceleration curve for operating the stepper motor over a range of motor velocities during an intake cycle. A processor of a system controller dynamically accesses the memory during the intake cycle to acquire the information representing the intake velocity profile and issues a series of pulses to the stepper motor based on this information. In response to the pulses, the stepper motor accelerates in accordance with the optimized acceleration curve represented by the intake velocity profile. The optimized acceleration curve is based on the available torque of the stepper motor across a range of motor velocities and enables the motor to operate with greater torque utilization and less margin than traditional linear acceleration profiles. | 02-09-2012 |
20120097026 | Piston Pump With Leak Diagnostic Port - Described are embodiments of a pump having a diagnostic port that enables users and support personnel to diagnose the source of a pump leak. The diagnostic port is monitored visually or with a pressure or liquid detection sensor. In some embodiments, fluid detected at the diagnostic port corresponds to a leak around a circumference defined at an outer sealing surface of a high pressure seal. In other embodiments, fluid detected at the diagnostic port corresponds to a leak around a plunger at the inside diameter of the high pressure seal. Multiple diagnostic ports can be provided to allow separate determinations of leaks about the different portions of the high pressure seal. The embodiments may eliminate the need to disassemble the pump to determine the source of leaks. Thus the effort required to diagnose and repair the pump can be substantially reduced, and fewer misdiagnosed components are ordered or replaced. | 04-26-2012 |
20120285872 | THERMAL CONTROL OF THERMAL CHAMBER IN HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY SYSTEMS - A sample manager of a liquid chromatography system implements a thermal system that uses a dual-loop feedback control system to control temperature within a thermal chamber. The sample manager includes an external heatsink disposed externally to the thermal chamber, an internal heatsink disposed within the thermal chamber, and one or more thermoelectric devices thermally coupled to the external and internal heatsinks to transfer heat therebetween in response to a pulse-width modulated power signal. A first temperature sensor disposed within the thermal chamber continuously measures a chamber temperature. A second temperature sensor coupled to the internal heatsink within the thermal chamber continuously measures temperature at the internal heatsink. A feedback control system controls a duty cycle of the pulse-width modulated power signal in response to a target chamber temperature and real-time temperature measurements produced by the first and second temperature sensors. | 11-15-2012 |
20130004388 | SELF-SEALING SAMPLE COMPARTMENT FOR A LIQUID CHROMATOGRAPHY SYSTEM - Described is a self-sealing thermal enclosure. In various embodiments, the self-sealing thermal enclosure includes an enclosure having a wall with an opening. The enclosure is configured to surround a temperature-controlled environment. The self-sealing thermal enclosure also includes a porous seal disposed adjacent to the wall at the opening. The porous seal is compressible and is fabricated from an open cell foam material. When the porous seal has absorbed a fluid such as a condensate, the temperature-controlled environment is sealed from an ambient environment such that the flow of air into or out of the enclosure is substantially reduced or eliminated. | 01-03-2013 |
20130019695 | APPARATUS FOR REDUCING VARIATION IN SAMPLE TEMPERATURES IN A LIQUID CHROMATOGRAPHY SYSTEM - Described is an apparatus for reducing a temperature variation of a liquid chromatography sample. A tray drive using at least one of linear or rotational motion moves a sample tray along a path inside a sample compartment of the liquid chromatography system. A control module coordinates the movement of the sample tray by the tray drive and the movement of a sample needle by a needle drive so that any sample in the sample tray can be injected into the mobile phase of the system during a sample load operation. The tray drive is also used to move the sample tray along the path during a temperature averaging period when no loading occurs. Differences in sample temperatures due to variations in the air temperature at different locations inside the sample compartment are reduced, leading to more accurate and repeatable chromatographic measurement results. | 01-24-2013 |
20130240044 | METHOD AND APPARATUS FOR CONTROL OF MASS COMPOSITION OF MOBILE PHASE - Described are a method and an apparatus for delivering a fluid having a desired mass composition. According to the method, temperatures of the fluids to be mixed are sensed and the densities of the fluids at the sensed temperatures are determined. The volume of each fluid is determined so that a mixture of the fluids at the sensed temperatures has the desired mass composition. The determined volumes of the fluids are combined to create the mixture. In one option, combining the determined volumes includes metering flows of the fluids sequentially into a common fluid channel. Alternatively, combining the determined volumes includes controlling a flow rate of each of the fluids and directing the fluids into a common fluid channel. | 09-19-2013 |
20130308415 | VALVE SWITCH MODULATION FOR REDUCING ERRORS DUE TO OSCILLATIONS OF THE INLET FLUID OF A PUMP SYSTEM - Described is a method of reducing liquid composition errors in a low-pressure mixing pump system. Packets representing the switching intervals of each component of the desired fluid mixture are provided to an intake of the mixing pump system. For each packet, a switching time associated with at least one of the components in the packet is modulated. Modulated switching times are based on time offsets that are specifically selected according to the undesirable frequency characteristic of an intake response of the mixing pump system. The average of the volumes contributed by the packets thus modulated is equal to a component volume that achieves a desired proportion of the component in the output flow of the mixing pump system. Modulated switching times enable the reduction or elimination of composition error in the output flow of the mixing pump system. | 11-21-2013 |
20130323103 | SEAL ASSEMBLIES FOR RECIPROCATING AND ROTARY APPLICATIONS - Low-pressure and high-pressure reciprocating and rotary applications use seal assemblies to prevent leakage. One embodiment of a seal assembly includes a major annular body having opposing spaced-apart annular lips extending from a heel portion with a bore extending through the heel portion. A first spring is disposed between the lips, biasing the lips apart. A minor annular body extends from one of the lips of the major annular body. The minor annular body has opposing spaced-apart walls that extend from a base region and form a pocket. A second spring is disposed in the pocket between the spaced-apart walls, biasing the walls apart. During actuator operation, pressurized fluid urges one wall of the minor annular body against a pump head surface to produce a face seal and one of the lips of the major annular body against a rod surface to produce a radial seal. | 12-05-2013 |
20130340609 | PUMP HEAD OUTLET PORT - Pumps used in liquid chromatography applications employ actuators for pressurizing and moving liquid. An actuator includes a pump head having a chamber, a gland, a movable rod extending through the gland into the chamber of the pump head, and a plunger seal disposed in the gland around the rod for sealing against fluidic leakage from the chamber. The plunger seal has an annular flange that provides an OD (outer diameter) seal against the gland. The flange defines a seal cavity. The pump head further includes an outlet port and an outlet channel. One end of the outlet channel is in communication with the outlet port and the other end of the outlet channel opens into the seal cavity of the plunger seal. The outlet channel provides a flow path for liquid in the chamber to travel towards the outlet port in response to movement of the rod. | 12-26-2013 |
20140044577 | HIGH PRESSURE PUMP WITH REDUCED SEAL WEAR - Described are embodiments of a pump that can be used, for example, in liquid chromatography applications. The pump includes a seal wash housing, pump head and seal assembly. A wear-resistant coating applied to a sealing surface or gland of the pump head or seal wash housing improves the hardness and chemical compatibility of the sealing surface. Oxidation of the sealing surface is reduced so that the sealing surface is less abrasive to the seal assembly and the lifetime of the seal assembly is increased. | 02-13-2014 |
20140086003 | VALVE SWITCH MODULATION FOR REDUCING ERRORS DUE TO OSCILLATIONS OF THE INLET FLUID OF A PUMP SYSTEM - Described is a method of reducing liquid composition errors in a low-pressure mixing pump system. Packets representing the switching intervals of each component of the desired fluid mixture are provided to an intake of the mixing pump system. For each packet, a switching time associated with at least one of the components in the packet is modulated. Modulated switching times are based on time offsets that are specifically selected according to the undesirable frequency characteristic of an intake response of the mixing pump system. The average of the volumes contributed by the packets thus modulated is equal to a component volume that achieves a desired proportion of the component in the output flow of the mixing pump system. Modulated switching times enable the reduction or elimination of composition error in the output flow of the mixing pump system. | 03-27-2014 |
20140150536 | COLUMN MANAGER WITH A MULTI-ZONE THERMAL SYSTEM FOR USE IN LIQUID CHROMATOGRAPHY - A thermal system for use in a column manager of a liquid chromatography system comprises a plurality of spatially separated individually controlled thermoelectric chips. A column module houses a plurality of thermally conductive troughs. Each trough resides in a separate thermal zone to be thermally conditioned individually by one of the individually controlled thermoelectric chips. Each trough is adapted to hold one or more liquid chromatography columns therein. A plurality of spatially separated thermal bridges includes a first thermal bridge thermally coupling one of the thermoelectric chips to a first one of the plurality of troughs and a second thermal bridge of the plurality of thermal bridges thermally coupling another of the thermoelectric chips to a second one of the plurality of troughs. | 06-05-2014 |
20150013803 | PRESSURE RELATED HYSTERESIS MANIPULATION IN A PRESSURIZED FLOW SYSTEM - Exemplary embodiments of the present disclosure are directed to manipulating pressure-related hysteresis in a pressurized flow system by setting the pressure of the system to a predetermined location in the hysteresis band to advantageously minimize an effect of the pressure related hysteresis on the pressure of the system or to advantageously benefit from the effects of the hysteresis on the pressure of the system. | 01-15-2015 |
20150014562 | LOW VOLUME, PRESSURE ASSISTED, STEM AND SEAT VENT VALVE AND ASSOCIATED METHODS - Exemplary embodiments are directed to vent valves, systems and methods generally involving a valve body that includes a seat retainer, a needle and a seat. The seat includes a bore extending there through and the needle includes a needle stem and a needle head. The seat is disposed inside the seat retainer. The needle stem is disposed inside the bore. The needle is configured to be pulled through the seat to stop flow through the bore. Exemplary embodiments are further directed to a system including a stem return spring mechanism and a solenoid return spring mechanism. A processing device is configured to actuate the solenoid return spring mechanism to permit the stem return spring mechanism to pull the needle through the seat to stop flow through the bore. | 01-15-2015 |
20150014563 | SYSTEM AND METHOD FOR MINIMIZATION OF FORCE VARIATION IN A SOLENOID WITHIN A PRESSURIZED FLOW SYSTEM - Exemplary embodiments are directed to systems and methods used to minimize force variation from a solenoid through an operating stroke. The systems and methods generate a near constant or substantially constant force solenoid assembly which can be used in a force driven device, such as, for example, a pressure regulator for accurately controlling pressure in a pressurized flow system. The systems and methods are based on an initial solenoid characterization and include an application of springs and placement of the solenoid within the system at a gap distance to minimize variation in force in the operating stroke of a commercially available solenoid. | 01-15-2015 |
20150027567 | BACK PRESSURE REGULATION - The invention generally provides a dynamic back pressure regulator. In exemplary embodiments, the back pressure regulator includes an inlet, an outlet, a seat disposed between the inlet and the outlet and defining at least part of a fluid pathway, and a needle displaceable relative to the seat to form a restriction region therebetween for restricting fluid flow between the inlet and the outlet. In some embodiments, the needle can be formed of a chemically resistant ceramic or have a metal plating to provide corrosion and/or erosion resistance. | 01-29-2015 |
20150034168 | LIMITING A RATE OF PRESSURIZATION IN A PRESSURIZED FLOW SYSTEM HAVING A CONFIGURABLE SYSTEM VOLUME - Exemplary embodiments of the present disclosure are directed to limiting a rate or pressurization in a reconfigurable pressurized flow system for which different system configurations can have different system volumes. In exemplary embodiments, the system can determine a limit for the rate of pressurization by configuring the system for a closed system rate of pressurization, measuring the closed system rate of pressurization at a set flow rate, and determining a relationship between the closed system rate of pressurization and the flow rate. The system can use the relationship to dynamically set the limit for different flow rates in the system. | 02-05-2015 |
20150040756 | REGULATOR FOR IMPROVED THERMAL AND PRESSURE CONTROL FOR CHROMATOGRAPHY - Exemplary embodiments of the present disclosure include systems, apparatuses, and methods that are directed to controlling pressure in a pressurized flow system, such as a C0 | 02-12-2015 |
20150040992 | DEVICE CAPABLE OF PRESSURIZATION AND ASSOCIATED SYSTEMS AND METHODS - Exemplary embodiments are directed to devices, methods and systems capable of pressurization, generally involving a flow system that includes a pressurized reservoir, at least one pump including a pump control valve, an outlet port, a shut-off valve and a vent valve. The flow system is configured to be pressurized. The shut-off valve is disposed between the pressurized reservoir and the at least one pump. The vent valve is disposed between the at least one pump and the outlet port. The shut-off valve, the vent valve and the pump control valve of the at least one pump are configured to actuate in a coordinated manner to control a pressurization of the flow system. Exemplary embodiments are further directed to devices, methods and systems for column switching, generally including at least a first column, a second column and a column switching valve. | 02-12-2015 |
20150043303 | VALVE SWITCH MODULATION FOR REDUCING ERRORS DUE TO OSCILLATIONS OF THE INLET FLUID OF A PUMP SYSTEM - Described is a method of reducing liquid composition errors in a low-pressure mixing pump system. Packets representing the switching intervals of each component of the desired fluid mixture are provided to an intake of the mixing pump system. For each packet, a switching time associated with at least one of the components in the packet is modulated. Modulated switching times are based on time offsets that are specifically selected according to the undesirable frequency characteristic of an intake response of the mixing pump system. The average of the volumes contributed by the packets thus modulated is equal to a component volume that achieves a desired proportion of the component in the output flow of the mixing pump system. Modulated switching times enable the reduction or elimination of composition error in the output flow of the mixing pump system. | 02-12-2015 |
20150047422 | INTRODUCING SAMPLES INTO SUPERCRITICAL FLUID CHROMATOGRAPHY SYSTEMS - A supercritical fluid chromatography system is provided with an injection valve subsystem for introducing a sample into a flow of mobile phase fluid. The injection valve subsystem includes an auxiliary valve and an inject valve. The operations of the auxiliary and inject valves are coordinated in such a manner as to reduce sample carry-over and system pressure perturbations occurring during sample injection. | 02-19-2015 |
20150047500 | FORCE BALANCE NEEDLE VALVE PRESSURE REGULATOR FOR CARBON DIOXIDE BASED CHROMATOGRAPHY - Exemplary embodiments of the present disclosure relate to systems and methods comprising a dynamic pressure regulator and a force balance needle that regulate pressure changes due to flow or composition changes in a pressurized flow system, such as, for example, a CO | 02-19-2015 |
20150059864 | METHOD, SYSTEM AND APPARATUS FOR AUTOMATIC CALIBRATION OF A NEEDLE VALVE DEVICE IN A PRESSURIZED FLOW SYSTEM - Exemplary embodiments are directed to apparatus, systems and methods used in connection with a needle valve device operating in a pressurized flow system. The apparatus, systems and methods provide for automatic positioning of a needle relative to a seat in the needle valve device to provide consistent calibration with minimal user interaction after a maintenance event or upon a start-up of the pressurized flow system. The apparatus, systems and methods utilize a calibration collar secured to a shaft of an actuator within the needle valve device. The calibration collar includes one or more locking mechanism and a spring. | 03-05-2015 |
20150059865 | MODULAR SOLENOID VALVE KITS AND ASSOCIATED METHODS - Exemplary embodiments are directed to modular solenoid valve kits and associated methods, generally involving a valve body that includes a plurality of actuator section components and a plurality of head section components. The plurality of actuator section components includes a drive solenoid, a solenoid return spring, a stroke calibration collar and an actuator-to-head calibration collar. The plurality of head section components includes a needle, a stem return spring, a seal and a seat. The plurality of actuator section components and head section components are adapted to be interchanged to create a pull-through normally open valve, a pull-through normally closed valve, a push-in normally open valve and a push-in normally closed valve. That is, the kits and methods allow for modification of one valve type (e.g., a pull-through normally open valve, a pull-through normally closed valve, a push-in normally open valve and a push-in normally closed valve) into a different type. | 03-05-2015 |
20150083947 | BACK PRESSURE REGULATION - The invention generally provides a dynamic back pressure regulator. In an exemplary embodiment, the back pressure regulator includes an inlet, an outlet, a seat disposed between the inlet and the outlet and defining at least part of a fluid pathway, and a needle displaceable relative to the seat to form a restriction region therebetween for restricting fluid flow between the inlet and the outlet. In some embodiments, the needle can include a corrosion and/or erosion resistant polymer tip. | 03-26-2015 |
20150101419 | Phase Detection in Multi-Phase Fluids - The present disclosure relates to phase detection in multi-phase fluids where two fluid phases can be present in the fluid. Phase detection apparatus and methods are disclosed for determining the phase(s) (e.g., supercritical, liquid, and/or gas) of a fluid in a multi-phase fluid system, such as carbon dioxide based separation and chromatography system. | 04-16-2015 |
20150129057 | STATIC BACK PRESSURE REGULATOR - The invention generally provides a static back pressure regulator. In exemplary embodiments, the static back pressure regulator includes a seat that defines part of a fluid pathway, a poppet, a spring arranged to bias the poppet toward the seat to restrict fluid flow through the fluid pathway, and a calibration element configured to adjust a force applied to the poppet by the spring. The calibration element can include a through hole that forms part of the fluid pathway. The poppet can include a first guiding portion that extends into the through hole of the calibration element and inhibits tipping of the poppet relative to the seat. | 05-14-2015 |
20150129494 | METHOD AND AN APPARATUS FOR CONTROLLING FLUID FLOWING THROUGH A CHROMATOGRAPHIC SYSTEM - A method for controlling fluid flowing through a chromatographic system includes determining a fluidic parameter related to density at a first fluidic location in the chromatographic system; and in response to the determined fluidic parameter, modifying a volumetric flow rate or a pressure at a second fluidic location in the chromatographic system to produce a selected mass flow rate of the fluid. | 05-14-2015 |
20150219603 | METHOD FOR HIGH PRESSURE GRADIENT CHROMATOGRAPHY USING PUMP STROKE CONTROL - Described is a method of generating a flow having a composition gradient such as a mobile phase gradient for liquid chromatography. A pair of pumps is operated such that the initiations of pump strokes for one pump are controlled to occur between the initiations of pump strokes for the other pump so that the sequences of pump strokes fort the two pumps are interspersed in time. Initiations of the pump strokes of the second pump are offset in time relative to initiations of the pump strokes of the first pump such that variations in the flow rates of the first and second pumps due to initiation do not overlap in time. The volume of liquid contributed by a pump stroke is controlled according to the relative contribution of the respective pump to the composition gradient. | 08-06-2015 |