JPH0447660Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a gas chromatograph/mass spectrometer in which a gas chromatograph and a mass spectrometer are connected via a glass separator, and particularly relates to the structure of the connecting portion between the separator and the ion source.

Connect the gas chromatograph and mass spectrometer,
When a sample developed using a gas chromatograph is introduced into a mass spectrometer for mass spectrometry, a separator (enricher) is inserted between the two in order to remove the carrier gas and concentrate the sample components. This separator is usually made of glass and is attached to the ion source of a mass spectrometer as shown in FIG. 1, for example. In FIG. 1, 1 is a side wall of the ion source of the mass spectrometer, 2 is an ionization chamber, 3 is an inlet opened in the side wall 2, 4 is a glass separator, and 5 is a concentrated sample component formed integrally with the separator. glass introduction tube for conveying the ions into the ion source, 6
7 is a metal flange for fixing the introduction pipe 5 to the introduction port 3; 7 is a nut that applies pressure to maintain airtightness between the flange 6 and the introduction pipe 5; 8
9 is a cone inserted between the nut 7 and the flange 6, and 9 is an oven for heating the separator 4 and the introduction pipe 5.

However, with such a conventional structure, leaks easily occur due to temperature changes at the cone 8 inside the oven 9, and the nut may seize or the cone may adhere to the flange and become impossible to remove. There's a problem. Furthermore, when the ion source acceleration voltage is high, glow discharge is likely to occur along the broken line, resulting in undesirable phenomena such as decomposition of the sample due to the discharge.

This invention was made in view of the above points,
In a gas chromatograph mass spectrometer in which a sample developed by a gas chromatograph is introduced into an ionization chamber of an ion source through a glass separator, a sample component that is formed integrally with the separator and concentrated in the separator is transported to the ionization chamber. A double tube structure is achieved by forming a flange having an outer tube part with a larger diameter than the introduction tube on the outer periphery part of the glass introduction tube, and a rubber packing is provided at the outer periphery of the flange. A gap is formed between the ion source and an oven that is connected to the introduction port of the ion source and that houses and heats the separator and the glass introduction tube therein, and the temperature of the gap is lowered. It is an object of the present invention to provide a gas chromatograph mass spectrometer which can eliminate the above-mentioned problems by arranging the rubber packing in the gas chromatograph mass spectrometer. Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 2 is a sectional view showing the structure of an embodiment of the present invention, and the same components as in FIG. 1 are given the same numbers. The difference from FIG. 1 is that a glass flange 11 having an outer tube part 10 with a larger diameter than the introduction tube 5 is fused in the middle of the introduction tube 5, and the outer tube part 10 is fused.
0 is connected to the flange 13 and side wall 2 via an O-ring packing 12 on the outer periphery of the flange 1 to maintain airtightness. O-ring packing 1
2 is placed in a gap formed between the ion source side wall 1 and the oven 9.

In such a configuration, the temperature in the gap between the oven 9 and the ion source side wall 1 is lower than in the oven, and since it is close to the side wall, there is little temperature change. Since the O-ring is arranged in this area, leakage is less likely to occur, and deterioration and seizure of the O-ring can be prevented, and there is no possibility that the separator cannot be removed due to seizure as in the conventional case. Furthermore, since the glass flange 11 with high insulation resistance is interposed between the introduction tube 5 and the flange 13, the insulation property is increased, and therefore, even when the ion source accelerating voltage is high, discharge is difficult to occur. decomposition of the sample due to Moreover, it has been confirmed that the temperature of the portion of the collar 11 facing the gap between the ion source side wall 1 and the oven 9 decreases, and that this temperature decrease further reduces the possibility of discharge occurring.

Furthermore, in this embodiment, an appropriate gap is provided between the outer tube 10 and the flange 13, and the introduction gap 5 (and thus the separator) is inserted by the amount of the gap using the O-ring as a fulcrum.
is designed to be able to swing, so that when replacing the gas chromatograph column, the force applied to the attachment part A of the collar 11 can be dispersed, and damage to the part A can be prevented.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional structure, and FIG. 2 is a sectional view showing the structure of an embodiment of the present invention. 1... Ion source side wall, 2... Ionization chamber, 3...
...Inlet port, 4...Glass separator, 5...Glass introduction tube, 10...Outer tube part, 11...Tsuba, 1
2...O-ring packing, 13...flange.

Claims (1)

[Scope of utility model registration request] In a gas chromatograph mass spectrometer in which a sample developed by a gas chromatograph is introduced into an ionization chamber of an ion source through a glass separator, a sample component that is formed integrally with the separator and concentrated in the separator is transported to the ionization chamber. A double tube structure is achieved by forming a flange portion having an outer tube portion with a larger diameter than the introduction tube on the outer periphery part of the glass introduction tube, and an O-ring packing is provided at the outer periphery of the flange portion. A gap is formed between the ion source and an oven for accommodating and heating the separator and glass introduction tube, and the temperature in the gap is reduced. A gas chromatograph mass spectrometer, characterized in that the O-ring packing is disposed at a portion.