Sample injection apparatus

Claim 2

A syringe-type sample injection apparatus adapted to be inserted through a self-sealing septum in a sample injection inlet of an analysis instrument for introducing a predetermined volume of fluid sample into a fluid stream flowing through the injection inlet comprising: a support block, said support block including an axial bore therethrough, said axial bore having threads formed therein; a tubular member including a forward needle section and a rearward plunger section, said tubular member extending from said support block and being supported thereby at one end of said rearward plunger section; said needle section including a hollow needle having an axial sample cavity of predetermined volume and diameter, said cavity having a discharge opening at one end thereof and an inlet opening at the other end thereof; said plunger section being attached to said needle section and having a plunger cavity aligned with said inlet opening of said sample cavity and said axial bore in said support block, said plunger section having a stream inlet port through the sidewall thereof, said inlet port being positioned in said sidewall closely adjacent said inlet opening to said sample cavity and communicating with said sample cavity in said needle section through said plunger cavity; a plunger slidably positioned in said plunger section, said plunger having a tip adapted to abut upon and close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position; a piston attached to said plunger and extending through said plunger cavity into said support block, said piston including a threaded section adapted to mate with said threads of said axial bore of said support block whereby said piston and said plunger may be moved inwardly and outwardly with respect to said opening in said cavity by rotating said piston; and a conically shaped shoulder formed on the outer surface of said needle section at a position between said discharge opening thereof and said inlet opening to said cavity in said needle section.

Claim 3

A syringe-type sample injection apparatus adapted to be inserted through a self-sealing septum in a sample injection inlet of an analysis instrument for introducing a predetermined volume of fluid sample into a fluid stream flowing through the injection inlet comprising: a tubular member including a forward needle section and a rearward plunger section; said needle section including a hollow needle having an axial sample cavity of predetermined volume and diameter, said cavity having a discharge opening at one end thereof and an inlet opening at the other end thereof; said plunger section being attached at one end to said needle section and having a plunger cavity aligned with said inlet opening to said sample cavity, said plunger section having a stream inlet port through the sidewall thereof, said inlet port being positioned in said sidewall closely adjacent to said inlet opening to said sample cavity and communicating with said sample cavity in said needle section through said plunger cavity; a plunger slidably positioned in said plunger section, said plunger having a tip adapted to abut upon and close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position; a piston attached to said plunger and extending through said plunger cavity and out the end of said plunger section not attached to said needle section; sealing means around said piston for sealing between said piston and the sidewall of said plunger cavity; means engaging said end of said piston extending out said plunger cavity for reciprocating said piston and said plunger between said forward and a retracted position; and a shaped shoulder formed on the outer surface of said needle section at a position between said discharge opening thereof and said inlet opening to said cavity in said needle section.

Claim 4

A syringe-type sample injection apparatus adapted to be inserted through a self-sealing septum in a sample injection inlet of an analysis instrument for introducing a predetermined volume of fluid sample into a fluid stream flowing through the injection inlet comprising: a tubular member including a forward needle section and a rearward plunger section; said needle section including a hollow needle having an axial sample cavity of predetermined volume and diameter, said cavity having a discharge opening at one end thereof and an inlet opening at the other end thereof; said plunger section being attached at one end to said needle section and having a plunger cavity aligned with said inlet opening to said sample cavity, said plunger section having a stream inlet port through the sidewall thereof, said inlet port being positioned in said sidewall closely adjacent to said inlet opening to said sample cavity and communicating with said sample cavity in said needle section through said plunger cavity; a plunger slidably positioned in said plunger section, said plunger having a tip adapted to abut upon and close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position; a piston attached to said plunger and extending through said plunger cavity and out the end of said plunger section not attached to said needle section; sealing means around said piston for sealing between said piston and the sidewall of said plunger cavity; means engaging said end of said piston extending out said plunger cavity for reciprocating said piston and said plunger between said forward and a retracted position; and a shaped shoulder formed on the outer surface of said needle section at a position between said discharge opening thereof and said inlet opening to said cavity in said needle section.

Claim 5

The sample injection apparatus defined in claim 2 in which said shaped shoulder comprises a conically shaped surface formed around the circumference of said needle section of said tubular member.

Claim 6

A sample injection apparatus for introducing a predetermined volume of fluid sample into a sample injection inlet of a gas analysis apparatus through which there flows a fluid stream, the sample inlet having an injection opening through which said fluid stream must flow, comprising: a tubular member including a forward needle section and a rearward plunger section; said needle section including a hollow needle adapted to be inserted into a sample inlet and having an axial sample cavity of predetermined volume and diameter, said cavity having a discharge opening at one end of said needle section and an inlet opening at the other end of said needle section; said plunger section being attached to said needle section and having a plunger cavity aligned with said inlet opening to said sample cavity, said plunger section having a stream inlet port through the sidewall thereof adjacent said inlet opening to said needle section; a plunger slideably positioned in said plunger section, said plunger having a valve tip adapted to abut of close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position; means in said plunger section for reciprocating said plunger between said forward and retracted positions; a shoulder formed on the outer surface of said needle section, said shoulder being so constructed and arranged on said needle section as to abut against said injection opening in the sample inlet thereby obstructing flow of the gas stream therethrough so that the gas stream is caused to flow through said stream inlet port of said plunger section into said sample cavity thereby to sweep a sample from said sample cavity when said plunger is retracted from said inlet opening to said sample cavity.

Claim 7

A sample injection apparatus for introducing a predetermined volume of fluid sample into a sample injection inlet of a gas analysis apparatus through which there flows a fluid stream, the sample inlet having an injection opening through which said fluid stream must flow, comprising: a tubular member including a forward needle section and a rearward plunger section; said needle section including a hollow needle adapted to be inserted into a sample inlet and having an axial sample cavity of predetermined volume and diameter, said cavity having a discharge opening at one end of said needle section and an inlet opening at the other end of said needle section; said plunger section being attached to said needle section and having a plunger cavity aligned with said inlet opening to said sample cavity, said plunger section having a stream inlet port through the sidewall thereof adjacent said inlet opening to said needle section; a plunger slideably positioned in said plunger section, said plunger having a valve tip adapted to abut of close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position; means in said plunger section for reciprocating said plunger between said forward and retracted positions; a shoulder formed on the outer surface of said needle section, said shoulder being so constructed and arranged on said needle section as to abut against said injection opening in the sample inlet thereby obstructing flow of the gas stream therethrough so that the gas stream is caused to flow through said stream inlet port of said plunger section into said sample cavity thereby to sweep a sample from said sample cavity when said plunger is retracted from said inlet opening to said sample cavity.

Claim 8

In combination: a gas chromatograph system having a sample injection inlet including an injection port through which a stream of carrier gas must flow in its path toward remaining comPonents of said gas chromatograph, said injection inlet having an opening closed by a self-sealing septum; a sample injection device including a tubular member having a forward needle section and a rearward plunger section; said needle section including a hollow needle having an axial sample cavity of predetermined volume and diameter, said cavity having a discharge opening at one end thereof and an inlet opening at the other end thereof, said needle section being of a size adapted to puncture said septum thereby permitting said needle section and at least a portion of said plunger section to be inserted into the injection port in the sample injection inlet of said chromatograph system, a shoulder formed on the outer surface of said needle section and being so constructed and arranged on said needle section as to abut against the injection port in said sample inlet thereby obstructing flow of the gas stream therethrough; said plunger section being attached to said needle section and having a plunger cavity aligned with said inlet opening to said sample cavity, said plunger section having a gas stream inlet port through the sidewall thereof, said inlet port being positioned in said sidewall closely adjacent to and communicating with said inlet opening to said needle section through said plunger cavity; a plunger slidably positioned in said plunger section, said plunger having a tip adapted to abut upon and close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position, so that the carrier gas stream is caused to flow through said sample cavity thereby to sweep a sample from said cavity; and means attached to said plunger section for reciprocating said plunger between said forward said retracted positions.

Claim 9

In combination: a gas chromatograph system having a sample injection inlet including an injection port through which a stream of carrier gas must flow in its path toward remaining comPonents of said gas chromatograph, said injection inlet having an opening closed by a self-sealing septum; a sample injection device including a tubular member having a forward needle section and a rearward plunger section; said needle section including a hollow needle having an axial sample cavity of predetermined volume and diameter, said cavity having a discharge opening at one end thereof and an inlet opening at the other end thereof, said needle section being of a size adapted to puncture said septum thereby permitting said needle section and at least a portion of said plunger section to be inserted into the injection port in the sample injection inlet of said chromatograph system, a shoulder formed on the outer surface of said needle section and being so constructed and arranged on said needle section as to abut against the injection port in said sample inlet thereby obstructing flow of the gas stream therethrough; said plunger section being attached to said needle section and having a plunger cavity aligned with said inlet opening to said sample cavity, said plunger section having a gas stream inlet port through the sidewall thereof, said inlet port being positioned in said sidewall closely adjacent to and communicating with said inlet opening to said needle section through said plunger cavity; a plunger slidably positioned in said plunger section, said plunger having a tip adapted to abut upon and close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position, so that the carrier gas stream is caused to flow through said sample cavity thereby to sweep a sample from said cavity; and means attached to said plunger section for reciprocating said plunger between said forward said retracted positions.

Claim 10

The combination defined in claim 5 in which said injection port has a beveled surface and said shoulder on said needle section of said sample injection device is conically shaped to mate with the beveled surface of said injection port when said needle section is inserted into said injection port.

Claim 11

The combination defined in claim 5 in which said injection port comprises the end of a chromatograph column having an outwardly flared end surface and said shoulder on said needle section of said sample injection device includes a conically shaped surface shaped to mate with the flared end surface of said chromatograph column when said needle section is inserted into said injection port formed by the end of said column.

Claim 12

A syringe-type sample injection apparatus adapted to be inserted through a self-sealing septum in a sample injection inlet of an analysis instrument for introducing a predetermined volume of fluid sample into a fluid stream flowing through the injection inlet comprising: a tubular member including a forward needle section and a rearward plunger section; said needle section including a hollow needle having an axial sample cavity of predetermined volume and a diameter, said cavity having a discharge opening at one end thereof and an inlet opening at the other end thereof; said plunger section being attached at one end of said needle section and having a plunger cavity aligned with said inlet opening to said sample cavity, said plunger section having a stream inlet port through the sidewall thereof, said inlet port communicating with said inlet opening to said sample cavity through said plunger cavity; a plunger slidably positioned in said plunger section, said plunger having a tip adapted to close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position; a piston attached to said plunger and extending through said plunger cavity and out the end of said plunger section not attached to said needle section; sealing means around said piston for sealing between said piston and the sidewall of said plunger cavity; means attached to the end of said piston extending out of said plunger section for reciprocating said piston including a hinged lever attached to the upper portion of said tubular member and engaging said piston, said lever being spring biased in a direction causing said piston and said plunger attached thereto to be normally disposed in a forward position closing said opening to said sample cavity; spring means exerting a force on said piston in a direction adapted to move said piston and said plunger into a retracted position when said spring lever is operated against said spring force exerted thereon; and a shaped shoulder formed on the outer surface of said needle section at a position between said discharge opening thereof and said inlet opening to said cavity and said needle section.

Claim 13

A syringe-type sample injection apparatus adapted to be inserted through a self-sealing septum in a sample injection inlet of an analysis instrument for introducing a predetermined volume of fluid sample into a fluid stream flowing through the injection inlet comprising: a tubular member including a forward needle section and a rearward plunger section; said needle section including a hollow needle having an axial sample cavity of predetermined volume and a diameter, said cavity having a discharge opening at one end thereof and an inlet opening at the other end thereof; said plunger section being attached at one end of said needle section and having a plunger cavity aligned with said inlet opening to said sample cavity, said plunger section having a stream inlet port through the sidewall thereof, said inlet port communicating with said inlet opening to said sample cavity through said plunger cavity; a plunger slidably positioned in said plunger section, said plunger having a tip adapted to close said inlet opening to said sample cavity when said plunger is in a forward position and to open said inlet opening for communication with said stream inlet port when said plunger is in a retracted position; a piston attached to said plunger and extending through said plunger cavity and out the end of said plunger section not attached to said needle section; sealing means around said piston for sealing between said piston and the sidewall of said plunger cavity; means attached to the end of said piston extending out of said plunger section for reciprocating said piston including a hinged lever attached to the upper portion of said tubular member and engaging said piston, said lever being spring biased in a direction causing said piston and said plunger attached thereto to be normally disposed in a forward position closing said opening to said sample cavity; spring means exerting a force on said piston in a direction adapted to move said piston and said plunger into a retracted position when said spring lever is operated against said spring force exerted thereon; and a shaped shoulder formed on the outer surface of said needle section at a position between said discharge opening thereof and said inlet opening to said cavity and said needle section.