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US 5,667,657 AGranted
Pressure injection apparatus and method for injecting a sample into an electrophoresis capillary
AssigneeDionex Corporation
InventorsMichael William Recknor, David A. Wolze
Life of this patent
Estimating the term…
Abstract
A present invention and method provides a pressure injection apparatus (20) that injects a quantitatively defined volume of liquid sample (21) from a container (22) into a capillary device (23). A servo pressure primary regulator (26) is included which precisely regulates the fluid from a supply pressure (P.sub.S) to a substantially constant regulated pressure (P.sub.R) in communication with the liquid sample (21) for a predetermined period of time. A feedback mechanism cooperates with a valving assembly (31) to continuously monitor and adjust the regulated pressure (P.sub.R) to be substantially constant and precise for delivery to the container (21).
Claims79
A capillary electrophoresis pressure injection apparatus comprising:
- a container containing liquid sample therein;
- a capillary device formed for receiving a quantitatively defined volume of liquid sample, coupled to said container;
- a supply source of pressurized fluid at a supply pressure to urge said liquid sample into an input of said capillary device;
- a fixed pressure regulator, coupled in series to an output of supply source, that regulates said fluid at said supply pressure to a generally constant pressure;
- a servo pressure secondary regulator, coupled in series to an output of fixed pressure regulator, that precisely regulates said fluid from said generally constant pressure to a substantially constant preregulated pressure for a selected period of time;
- a servo pressure primary regulator, coupled in series to an output of secondary regulator, to further precisely regulate said fluid from said substantially constant preregulated pressure to a substantially constant regulated pressure for said selected period of time;
- and
- a distribution device, coupled to an output of said primary regulator, selectively distributing said fluid at said substantially constant and precisely regulated pressure to said container;
- a primary accumulator, coupled in series between the output of said primary regulator and an input of said distribution device, having an internal reservoir at said substantially constant regulated pressure;
- and
- a secondary accumulator, coupled in series between the output of said secondary regulator and an input of said primary regulator, having an internal cavity at said substantially constant preregulated pressure.
8 more elements
A method for injecting a quantitatively defied volume of liquid sample from a container into a capillary device comprising the steps of:
- supplying a pressurized fluid at a supply pressure;
- precisely regulating said fluid from said supply pressure to a substantially constant predetermined first command pressure through a servo pressure primary regulator by adjusting the regulated pressure regulated by said primary regulator toward said first command pressure only when the regulated pressure deviates from a deadband region corresponding to said first command pressure;
- and
- selectively exposing said liquid sample contained in skid container to said fluid at said substantially constant and precisely regulated pressure for a predetermined period of time to inject the defined volume of said liquid sample from said container into said capillary device.
1 more element
A method for injecting a quantitatively defined volume of liquid sample from a container into a capillary device comprising the steps of:
- supplying a pressurized fluid at a supply pressure;
- generally regulating said fluid at said supply pressure to a generally constant pressure through a fixed pressure regulator;
- precisely regulating said fluid from said generally constant pressure to a substantially constant regulated pressure through a servo pressure primary regulator;
- and
- selectively exposing said liquid sample contained in said container to said fluid at said substantially constant and precisely regulated pressure for a predetermined period of time to inject the defined volume of said liquid sample from said container into said capillary device.
2 more elements
A pressure injection apparatus that injects a quantitatively defined volume of liquid sample from a container into a capillary device, said pressure injection apparatus comprising:
- a container;
- a capillary device;
- a supply source of pressurized fluid at a supply pressure to urge said liquid sample into an input of said capillary device;
- a fixed pressure regulator, coupled in series to said output of said supply source, that regulates said fluid at said supply pressure to a generally constant pressure;
- a servo pressure primary regulator, coupled in series between an output of said fixed pressure regulator and an input of said capillary device, that precisely regulates said fluid from said supply pressure to a substantially constant regulated pressure for a selected period of time;
- and
- a distribution device, coupled to an output of said primary regulator, selectively distributing said fluid at said substantially constant and precisely regulated pressure to said container.
4 more elements
A pressure injection apparatus that injects a quantitatively defined volume of liquid sample from a container into a capillary device, said pressure injection apparatus comprising:
- a container;
- a capillary device;
- a supply source of pressurized fluid at a supply pressure to urge said liquid sample into an input of said capillary device;
- a servo pressure primary regulator, coupled in series between an output of said supply source and an input of said capillary device, that precisely regulates said fluid from said supply pressure to a substantially constant regulated pressure for a selected period of time;
- a servo pressure secondary regulator, coupled in series between an output of said supply source and an input of said primary regulator, that precisely preregulates said fluid from said supply pressure to a substantially constant preregulated pressure supplied to said primary regulator for said selected period of time;
- and
- a distribution device, coupled to an output of said primary regulator, selectively distributing said fluid at said substantially constant and precisely regulated pressure to said container.
4 more elements
A method for injecting a quantitatively defined volume of liquid sample from a container into a capillary device comprising the steps of:
- supplying a pressurized fluid at a supply pressure;
- precisely preregulating said fluid from said supply pressure to a substantially constant preregulated pressure through a servo pressure secondary regulator by:
- outputting a second feedback signal, from a secondary pressure sensor, proportional to real time measurement of the preregulated pressure;
- outputting a second command signal, from a secondary reference source, having a value representing a predetermined second command pressure;
- comparing said second feedback signal and said second command signal through a second computer, and outputting a second compensation signal in response to a second difference between said second feedback signal and said second command signal;
- and
- adjusting said preregulated pressure, through a secondary valving assembly responsive to said second compensation signal and in communication with the fluid, to be substantially equal to said second command pressure such that a magnitude of said second difference is reduced;
- precisely regulating said fluid from said supply pressure to a substantially constant regulated pressure through a servo pressure primary regulator by:
- outputting a first feedback signal, from a pressure sensor, proportional to real time measurement of the regulated pressure;
- outputting a first command signal, from a first reference source, having a value representing a predetermined first command pressure;
- comparing said first feedback signal and said first command signal through a first computer, and outputting a first compensation signal in response to a first difference between said first feedback signal and said first command signal;
- and
- adjusting said regulated pressure, through a valving assembly responsive to said first compensation signal and in communication with the fluid, to be substantially equal to said command pressure such that a magnitude of said first difference is reduced;
- and
- selectively exposing said liquid sample contained in said container to said fluid at said substantially constant and precisely regulated pressure for a predetermined period of time to inject the defined volume of said liquid sample from said container into said capillary device.
12 more elements
A pressure injection apparatus that injects a quantitatively defined volume of liquid sample from a container into a capillary device, said pressure injection apparatus comprising:
- a container;
- a capillary device;
- a supply source of pressurized fluid at a supply pressure to urge said liquid sample an input of said capillary device;
- a servo pressure regulator, coupled in series between an output of said supply and an input of said capillary device, that precisely regulates said fluid from said supply pressure to a substantially constant regulated pressure for a selected period of time, said servo pressure regulator including:
- a pressure sensor outputting a feedback signal proportional to real time measurement of the regulated pressure;
- a reference source outputting a command signal having a value representing a predetermined command pressure;
- a computer coupled to receive as inputs said feedback signal and said command signal, and outputting a compensation signal in response to a difference between said feedback signal and said command signal;
- and
- a valving assembly, responsive to said compensation signal and in communication with the fluid, formed to adjust said regulated pressure to be substantially equal to said command pressure such that a magnitude of the difference between said feedback signal and said command signal is reduced, said valving assembly including:
- a vent proportional microvalve responsive to said compensation signal, and controllably movable between a closed position and an opened position, controllably venting the fluid to reduce said regulated pressure thereof;
- and
- an inlet proportional microvalve responsive to said compensation signal, and controllably movable between a shut position and an unshut position, enabling fluid communication of the fluid at the supply pressure with the fluid at the regulated pressure to increase said regulated pressure,
- said computer including a valve controller coupled to the vent microvalve and the inlet microvalve for controlled operation of the vent microvalve between said closed position and said opened position, and of the inlet microvalve between said shut position and said unshut position;
- and
- a distribution device, coupled to an of said servo pressure regulator, selectively distributing said fluid at said substantially constant and precisely regulated pressure to said container.
12 more elements
Dependencies are inferred from the claim text.