JPH0371665B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in gas chromatographs.

Figure 1 is a configuration diagram showing a conventional gas chromatograph, in which an analyzer valve AV controls the flow rate of the test gas SG, a fine powder such as silica gel is filled as a carrier, and the test gas SG is passed through the analyzer valve AV. Column C through which is distributed, and
Detector D, which uses a thermal conductivity meter or the like to detect the gas sent out from column C, is housed in a constant temperature chamber CT, and is stored in an explosion-proof container EP. , a heater H that heats the pressurized air PA ₁ to turn it into hot air HA and then supplies it to the constant temperature chamber CT; a heater H is controlled according to the detection output obtained from the temperature sensor TS in the constant temperature chamber CT;
Temperature control unit TC to keep the temperature inside CT constant,
Open and close the branched pressure air PA ₁ to open and close the analyzer valve.
A solenoid valve SV that controls AV using air pressure, and
A preamplifier PA and the like that amplify the detection output of the detector D are housed.

Note that the test gas SG that has passed through the column C and the detector D is discharged as exhaust gas VG, and
The hot air HA supplied to the constant temperature chamber CT is exhausted as exhaust VA, while the pressure inside the explosion-proof container EP is
PA ₂ is supplied, and the pressure inside the explosion-proof container EP is positive relative to atmospheric pressure, and this pressure is monitored by a pressure gauge PG.

In addition, the output OUT of the preamplifier PA is sent to an external arithmetic processing unit, etc., where it is subjected to arithmetic processing and is used to drive a recorder, etc., while the solenoid valve SV is , and is controlled by an external control signal SC.

However, in the case of the configuration shown in Figure 1,
The CT, heater H, temperature control unit TC, solenoid valve SV, preamplifier PA, etc. are housed in the explosion-proof container EP, and the pressure inside the explosion-proof container EP is kept positive to prevent ignition from outside. For explosion-proof container EP
has a complicated and large structure, making it expensive as a whole, making it difficult to inspect the inside of the constant temperature oven CT, and having the processing section installed outside, which increases the amount of wiring between each other. is occurring.

The present invention has the purpose of fundamentally eliminating such drawbacks of the conventional art, and houses only the analyzer valve and column in a non-explosion-proof thermostatic chamber, and houses the other parts in a separate explosion-proof container. An extremely effective method that uses a combination of both.
It provides a gas chromatograph.

The details of the present invention will be explained below with reference to the configuration diagram of FIG. 2 showing an embodiment.

In Figure 2, the constant temperature chamber CT and explosion-proof container are shown.
The constant temperature chamber CT houses only the analyzer valve AV and the column C, and the explosion-proof container EP contains a heater H for supplying hot air to the constant temperature chamber CT. The temperature control unit TC controls the heater H according to the detection output of the temperature sensor TS, which is accommodated in the protrusion TP of the explosion-proof container EP and protrudes into the constant temperature chamber CT, and detects the gas sent out from the column C. Detector D, a preamplifier PA that amplifies its detection output, and an arithmetic processing unit that processes the output of this and releases it as data output DO.
The PRS and a solenoid valve SV that controls the analyzer valve AV using the branched pressure PA ₁ are housed.

In addition, pressure air PA ₁ , hot air HA, gas from column C, air pressure from solenoid valve SV, and exhaust gas VG
Flame arresters FA ₁ to _{FA 5} are provided at the portions where the pipes penetrate the side wall of the explosion-proof container EP to prevent ignition from the outside and the spread of fire from the inside to the outside.

In addition, the flame arresters FA ₁ to _{FA 5} are as follows:
The one disclosed in Japanese Utility Model Publication No. 54-30582 filed separately by the present applicant is preferred.

Therefore, according to this embodiment, the detector D, which requires explosion-proof measures, is not installed in the thermostatic chamber CT.
Constant temperature chamber CT can be made non-explosion proof. This makes maintenance and inspection of columns C, etc. in the thermostatic chamber CT easy, and since the thermostatic chamber CT is not housed in the explosion-proof enclosure EP, it is possible to make the explosion-proof enclosure EP compact, and the flame arrester FA ₁ ~ The adoption of FA ₅ eliminates the need to create positive pressure inside and simplifies the structure of the explosion-proof enclosure EP.
The whole can be manufactured at low cost.

In addition, since it does not contain a constant temperature oven CT, it is necessary to use an explosion-proof container.
Free up space in the EP, and the calculation processing unit PRS
Since the wiring for the arithmetic processing unit PRS is carried out inside the explosion-proof container EP, the amount of wiring with the outside is reduced.

However, depending on the conditions, the arithmetic processing unit PRS may be provided externally, and the temperature sensor TS can be connected to the protrusion TP.
It is also possible to place it directly inside the thermostatic chamber CT instead of storing it in the
The present invention is open to various modifications.

As is clear from the above description, according to the present invention, a thermostatic chamber containing a column, etc., and an explosion-proof container containing a heater, a detector for detecting gas sent out from the column, etc. are provided separately, and the thermostatic chamber is separately provided. Since the tank has a non-explosion-proof structure, the explosion-proof container can be made small and inexpensive, and maintenance and dotted lines inside the thermostatic chamber are easy, so a remarkable effect can be obtained in various gas chromatographs.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a conventional example, and FIG. 2 is a block diagram showing an embodiment of the present invention. EP...Explosion-proof container, CT...constant temperature layer, AV...analyzer valve, C...column, H...heater,
TC...Temperature control section, TS...Temperature sensor, D...
Detector, SV...Solenoid valve, PA...Preamplifier,
FA ₁ to FA ₅ ...Flame arrester, TP...Protrusion.

Claims (1)

[Claims] 1. A constant temperature chamber with a non-explosion-proof structure that houses an analyzer valve and a column, a heater for supplying hot air to the constant temperature chamber, and a temperature at which the heater is controlled according to the detection output of a temperature sensor protruding into the constant temperature chamber. It is characterized by comprising an explosion-proof container housing a control unit, a detector for detecting the gas sent out from the column, a preamplifier for amplifying the detection output of the detector, and a solenoid valve for controlling the analyzer valve. gas chromatograph.