Mechanical gas chromatography injection valves and column multiplexing techniques

Claim 2

A gas chromatography injection valve for controlling the flow of a sample vapor to an analytical separation column, comprising: a housing having an internal passageway and an outlet port communicating with said separation column, a linearly moveable shuttle within said housing having an injection port communicating with said sample vapor, actuator means for moving said shuttle within said housing to cause said injection port to be moveable between an injection position with said injection port in registry with said outlet port providing fluid communication between said ports, to a non-injection position with said injection port and said outlet port out of registry, inlet means for communicating said housing internal passageway with a source of a flushing gas, and means for controlling the flow of said flushing gas through said housing such that said sample vapor flowing into said housing does not communicate between said injection port and said outlet port when said shuttle is in said non-injection position said means for controlling including at least one capillary flow restrictor allowing said flushing gas to be continuously vented from said housing and at least one sealing element acting as a bearing for allowing said linear movement of said shuttle while controlling leakage of said flushing gas.

Claim 3

A gas chromatography injection valve according to claim 1 wherein said housing defines two or more of said outlet ports with each of said outlet ports communicating with separate analytical separation columns.

Claim 4

A gas chromatography injection valve according to claim 2 wherein in said non-injection position said injection port is positioned between adjacent of said outlet ports.

Claim 5

A gas chromatography injection valve according to claim 1 wherein said shuttle comprises an injection tube linearly translatable within said housing and extending exteriorly of said housing, and wherein said injection port comprises an aperture along said injection tube.

Claim 6

A gas chromatography injection valve according to claim 4 wherein said outlet port is formed by an outlet tube oriented perpendicular to said injection tube with said outlet port opening at the end of said outlet tube adjacent said injection tube.

Claim 7

A gas chromatography injection valve according to claim 5 wherein said means for controlling the flow of said flushing gas comprises gas flow passages causing said flushing gas to flow along said outlet tube and out of said housing, and along said injection tube and out of said housing.

Claim 8

A gas chromatography injection valve according to claim 5 wherein said means for controlling the flow of said flushing gas comprises gas flow passages causing said flushing gas to flow along said outlet tube.

Claim 9

A gas chromatography injection valve according to claim 1 wherein said means for controlling the flow of said flushing gas further includes a vent port positioned adjacent said injection port when said shuttle is in said non-injection position and wherein said capillary flow restrictor communicates with said vent port to permit control of the flow of said flushing gas through said vent port.

Claim 10

A gas chromatography injection valve according to claim 1 further comprising an actuator external of said housing for causing displacement of said shuttle and at least one sealing element for controlling leakage of said flushing gas from between said housing and shuttle.

Claim 11

A gas chromatography injection valve for controlling the flow of a sample vapor to an outlet comprising: a housing having an internal passageway and at least two outlet ports with at least one of said outlet ports for connection to an analytical separation column, a shuttle tube linearly displaceable within said housing and having an injection port communicating with said sample vapor, actuator means for moving said shuttle within said housing to cause said injection port to be moveable between an injection position with said injection port in registry with one of said outlet ports providing fluid communication therebetween, to a non-injection position with said injection port out of registry with each of said outlet ports, inlet means for communicating said housing passageway with a source of a flushing gas, and means for controlling the flow of said flushing gas through said housing such that said sample vapor flowing into said housing does not communicate between said injection port and any of said outlet ports when said shuttle is in said non-injection position.

Claim 12

A gas chromatography injection valve for controlling the flow of a sample vapor to an outlet comprising: a housing having an internal passageway and at least two outlet ports with at least one of said outlet ports for connection to an analytical separation column, a shuttle tube linearly displaceable within said housing and having an injection port communicating with said sample vapor, actuator means for moving said shuttle within said housing to cause said injection port to be moveable between an injection position with said injection port in registry with one of said outlet ports providing fluid communication therebetween, to a non-injection position with said injection port out of registry with each of said outlet ports, inlet means for communicating said housing passageway with a source of a flushing gas, and means for controlling the flow of said flushing gas through said housing such that said sample vapor flowing into said housing does not communicate between said injection port and any of said outlet ports when said shuttle is in said non-injection position.

Claim 13

A gas chromatography injection valve according to claim 10 wherein each of said outlet ports is formed by an outlet tube oriented normal to said shuttle tube with one of said outlet ports opening at the end of said outlet tube adjacent said shuttle tube.

Claim 14

A gas chromatography injection valve according to claim 11 wherein said means for controlling the flow of said flushing gas comprises gas flow passages causing said flushing gas to flow along said outlet tube and out of said housing, and along said shuttle tube and out of said housing.

Claim 15

A gas chromatography injection valve according to claim 11 wherein said outlet tubes are separated and generally parallel to one another and in said non-injection position said injection port is positioned between adjacent of said outlet ports.

Claim 16

A gas chromatography injection valve according to claim 10 wherein each of said outlet ports communicating with separate analytical separation columns.

Claim 17

A gas chromatography injection valve according to claim 14, wherein said means for controlling the flow of said flushing gas includes a vent port positioned adjacent said injection port when said shuttle is in said non-injection position.

Claim 18

A gas chromatography injection valve for controlling the flow of a supplied fluid to an outlet, comprising: a housing having an internal passageway and a first port, a plug rotationally displaceable within said housing and having a second port, actuator means for rotating said plug within said housing to cause said second port to be moveable between an injection position with said first and second ports in registry providing fluid communication between said ports, to a non-injection position with said ports out of registry, inlet means for communicating said housing internal passageway with a source of a flushing gas, and means for controlling the flow of said flushing gas through said housing such that said supplied fluid flowing into said housing does not communicate between said first and second ports when said plug is in said non-injection position.

Claim 19

A gas chromatography injection valve for controlling the flow of a supplied fluid to an outlet, comprising: a housing having an internal passageway and a first port, a plug rotationally displaceable within said housing and having a second port, actuator means for rotating said plug within said housing to cause said second port to be moveable between an injection position with said first and second ports in registry providing fluid communication between said ports, to a non-injection position with said ports out of registry, inlet means for communicating said housing internal passageway with a source of a flushing gas, and means for controlling the flow of said flushing gas through said housing such that said supplied fluid flowing into said housing does not communicate between said first and second ports when said plug is in said non-injection position.

Claim 20

A gas chromatography injection valve according to claim 16 wherein said supplied fluid is a sample vapor and said second port communicates with said sample vapor and said first port communicates with an analytical separation column.

Claim 21

A gas chromatography injection valve according to claim 17 wherein said first port is formed by an outlet tube oriented with an end of said outlet tube adjacent said second port when said plug is in said injection position.

Claim 22

A gas chromatography injection valve according to claim 18 wherein said means for controlling the flow of said flushing gas comprises gas flow passages causing said flushing gas to flow along said outlet tube.

Claim 23

A gas chromatography injection valve according to claim 18 wherein said housing defines more than one of said first ports with each of said first ports defining distinct flow paths within said housing.

Claim 24

A gas chromatography injection valve according to claim 20 wherein in said non-injection position said plug is located with said second port positioned between adjacent of second ports.

Claim 25

A gas chromatography injection valve according to claim 20 wherein said means for controlling the flow of said flushing gas includes a vent port positioned adjacent said second port when said plug is in said non-injection position.

Claim 26

A gas chromatography system for the analysis of an analyte comprising: at least two analytical separation columns, said columns exhibiting differing separation characteristics, detector means for sensing the presence of components of said analyte eluting from said columns, and injection means for injecting an unseparated sample of said analyte into said columns whereby said separation characteristics of said columns are selected and said unseparated sample is sequentially injected into said columns such that said components eluting from each of said columns is intended to emphasize certain components of said analyte and wherein said components are sensed by said detector means at distinct time intervals.

Claim 27

A gas chromatography system for the analysis of an analyte comprising: at least two analytical separation columns, said columns exhibiting differing separation characteristics, detector means for sensing the presence of components of said analyte eluting from said columns, and injection means for injecting an unseparated sample of said analyte into said columns whereby said separation characteristics of said columns are selected and said unseparated sample is sequentially injected into said columns such that said components eluting from each of said columns is intended to emphasize certain components of said analyte and wherein said components are sensed by said detector means at distinct time intervals.

Claim 28

A gas chromatography system according to claim 23 wherein said detector means comprises a single detector receiving components of said analyte eluting from each of said columns.

Claim 29

A gas chromatography system according to claim 23 wherein said separation characteristics of said columns and said injection sequence are selected such that said certain components of said analyte eluting from one of said columns eludes during a time when the output of another of said columns is negligible.

Claim 30

A gas chromatography system according to claim 23 further comprising means for backflushing said columns.

Claim 31

A gas chromatography system according to claim 23 wherein said injection means comprises a mechanical injection valve having a housing having an internal passageway and at least two outlet ports communicating with said analytical columns and a moveable shuttle element having an injection port with said shuttle moveable from an injection position wherein said injection port and one of said outlet ports are aligned causing injection, to a non-injection position with said injection port out of registry with each of said outlet ports.

Claim 32

A gas chromatography system according to claim 23 wherein said injection means causes an injection into one of said columns to occur after a predetermined time delay after injection into another of said columns.

Claim 33

A gas chromatography system for the analysis of an analyte comprising: at least two analytical separation columns, said columns exhibiting differing separation characteristics, a detector receiving analyte components eluted from each of said columns for sensing the presence of analyte components being eluted, a mechanical injection valve for injecting an unseparated sample of said analyte into said columns said injection valve having a housing with an internal passageway and at least two outlet ports communicating with said analytical columns and a moveable shuttle element having an injection port from which said unseparated sample flows and said shuttle element moveable from an injection position wherein said injection port is aligned with one of said outlet ports to a non-injection position in which said injection port is out of registry with each of said outlet ports, and controller means for operating said injection valve such that said analyte is sequentially injected into said columns in a timed sequence such that the components of interest are eluted from said columns and sensed by said detector at distinct time intervals.

Claim 34

A gas chromatography system for the analysis of an analyte comprising: at least two analytical separation columns, said columns exhibiting differing separation characteristics, a detector receiving analyte components eluted from each of said columns for sensing the presence of analyte components being eluted, a mechanical injection valve for injecting an unseparated sample of said analyte into said columns said injection valve having a housing with an internal passageway and at least two outlet ports communicating with said analytical columns and a moveable shuttle element having an injection port from which said unseparated sample flows and said shuttle element moveable from an injection position wherein said injection port is aligned with one of said outlet ports to a non-injection position in which said injection port is out of registry with each of said outlet ports, and controller means for operating said injection valve such that said analyte is sequentially injected into said columns in a timed sequence such that the components of interest are eluted from said columns and sensed by said detector at distinct time intervals.

Claim 35

A gas chromatography injection valve for controlling the flow of a continuously supplied sample vapor to at least one outlet comprising: a housing having an internal chamber and at least one outlet port for connection to an analytical separation column, said chamber further defining an elongated bore, a shuttle tube linearly displaceable within said housing bore and having a hollow inside passageway and a vapor injection port in the form of an aperture through a wall of said tube, actuator means for moving said shuttle tube within said housing bore to cause said injection port to be moveable between an injection position with said injection port and said outlet port in registry providing fluid communication between said ports, and to first and second non-injection positions with said ports out of registry and said non-injection positions corresponding to said injection port on opposite sides of said outlet port along said bore, inlet means for communicating said housing chamber with a source of a flushing gas, and first and second vent passageways within said housing for permitting leakage of said flushing gas from said housing, said vent passageways positioned adjacent said injection port when said shuttle tube is in said non-injection positions, capillary flow restrictors connected to said outlet ports for controlling the flow of said flushing gas from said vent passageways, and at least one sealing element within said bore providing a bearing for said shuttle tube and controlling leakage of said flushing gas along said tube.

Claim 36

A gas chromatography injection valve for controlling the flow of a continuously supplied sample vapor to at least one outlet comprising: a housing having an internal chamber and at least one outlet port for connection to an analytical separation column, said chamber further defining an elongated bore, a shuttle tube linearly displaceable within said housing bore and having a hollow inside passageway and a vapor injection port in the form of an aperture through a wall of said tube, actuator means for moving said shuttle tube within said housing bore to cause said injection port to be moveable between an injection position with said injection port and said outlet port in registry providing fluid communication between said ports, and to first and second non-injection positions with said ports out of registry and said non-injection positions corresponding to said injection port on opposite sides of said outlet port along said bore, inlet means for communicating said housing chamber with a source of a flushing gas, and first and second vent passageways within said housing for permitting leakage of said flushing gas from said housing, said vent passageways positioned adjacent said injection port when said shuttle tube is in said non-injection positions, capillary flow restrictors connected to said outlet ports for controlling the flow of said flushing gas from said vent passageways, and at least one sealing element within said bore providing a bearing for said shuttle tube and controlling leakage of said flushing gas along said tube.

Claim 37

A gas chromatography injection valve according to claim 30 wherein said outlet port is formed by an outlet tube oriented normal to said shuttle tube with said housing port opening at the end of said outlet tube adjacent said shuttle tube.