JPS5919623B2 - Mass spectrometer sample introduction device - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a mass spectrometer that analyzes samples such as respiratory gas, and particularly relates to a sample introduction device for restricting the flow rate of the sample and guiding it to the main body of the mass spectrometer. .

[Technical background of the invention and its problems] In a mass spectrometer, the amount of sample flowing into the analysis tube is generally limited between the sample introduction tube through which the sample is collected and introduced and the analysis tube of the mass spectrometer body. A sample introduction device with a valve mechanism is installed.

Such sample introduction devices are usually located in the viscous flow region or intermediate flow region of the sample (gas) to be introduced, and have excellent responsiveness to samples whose state changes rapidly and versatility for various samples. A structure that does not reduce the degree of vacuum is required. As a device that substantially satisfies these requirements, a sample introduction device for a mass spectrometer having a structure as shown in FIG. 1 has already been proposed (Japanese Patent Application No. 1983-1.1.1).
No. 527). In the figure, 1 is a sample introduction tube for collecting a sample and introducing it into the sample introduction device, and a sample introduction port 3 of a first container 2 called a sampling chamber is connected to this tube 1. . A second container 5 serving as a valve box is integrally formed with the first container 2 with a partition wall 4 interposed therebetween. The second container 5 is provided with a sample outlet 6, which is connected to an ionization chamber 8 in an analysis tube provided in the mass spectrometer main body T. The partition wall 4 between the first and second containers 2 and 5 is provided with a thin tube 9 called a capillary, which serves as a leak member and communicates between the two containers 2 and 5, passing through the partition wall 4 vertically. The opening surface of the capillary 9 on the first container 2 side (the opening surface on the inlet side) together with the upper end surface of the partition wall 4 forms a valve seat. And the first
A valve mechanism 10 including a valve body 11 that is movable up and down facing the valve seat is attached to the upper end opening of the container 2 . That is, the valve body 11 is moved up and down by the electromagnet 12 to open and close the entrance side opening of the capillary 9, thereby blocking the introduction of the sample. Furthermore, the flow rate of the sample from the first container 2 to the second container 5 through the capillary 9, that is, the mass spectrometer body □
The flow rate of sample introduced into the sample is limited to an appropriate value.

Note that an exhaust port 13 is formed in the valve body 11, and this exhaust port 13 is connected to a suction device 15 via a valve 14.

By the way, the sample to be analyzed by a mass spectrometer is not always clean, and usually contains dust, dust, etc., and in particular, breathing gas may also contain water vapor, dirt, etc. as foreign substances.

In this case, the capillary 9 serving as the leak member is a glass tube with an inner diameter of approximately 30 to 40 μm, and therefore is likely to be clogged by foreign matter contained in the sample. Naturally, this would not only make analysis impossible, but also make the capillary 9
If you continue to use the device with the blockage left unattended, the effects will spread to other parts of the device, and you may be forced to replace the entire device. If the capillary 9 is blocked in this way, it can be replaced immediately.

However, as the capillary 9 is built into the sample introduction device and fixed to the partition wall 4 with adhesive as shown in FIG. It takes a lot of effort and time. For this reason, in the past, the capillary 9 was prevented from clogging by attaching a filter to the tip of the gas introduction tube 1 to prevent foreign matter from entering. This is not desirable as it sacrifices sexual improvement. [Object of the Invention] An object of the present invention is to provide a sample introduction device for a mass spectrometer that allows leakage members such as capillaries to be easily replaced in a short time.

[Summary of the Invention] The present invention provides an opening in a position opposite to a partition wall between a second container and a first container that communicates with a mass spectrometer main body, and supports a leak member in the opening. The second container is characterized in that a support body having a communication portion for communicating the outlet side opening surface of the container with the second container is detachably attached to the container so as to airtightly seal the opening.

〔Effect of the invention〕

According to this invention, the leak member can be quickly replaced only by attaching and detaching the support.

Therefore, when the leak member is blocked, analysis can be continued with only a short pause period required for replacing the leak member, and time and economic losses are significantly reduced. In addition, since various capillaries with different inner diameters can be replaced as leak members, it is possible to set the sample inflow amount that suits the characteristics of the device or analysis conditions, etc. Moreover, since it is only necessary to replace the leak member,
It has the advantage that it does not affect other properties in any way. [Embodiment of the Invention] FIG. 2 is a sectional view of a sample introduction device of a mass spectrometer according to an embodiment of the present invention, and FIG. 3 is a perspective view showing the main parts thereof. The same or corresponding parts as in FIG. 1 are given the same reference numerals.

In FIG. 2, an opening 5a is provided at a position facing the partition wall 4 between the second container 5, which also serves as a valve box, and the first container 2, and a capillary 9 serving as a leak member is provided here.
A support body is attached to support the. In this example, the supports include a first support 21 that also serves as a lid that fits onto the wall of the second container 5 with a screw, and a first support 21 that is interposed between the first support 21 and the capillary 9. 2 supports 22. As shown in FIG. 3, the second support body 22 is provided as a communication portion for communicating the outlet side opening surface of the hollow 9a of the capillary 9 with the inside of the second container 5. A hollow 22a is formed in the first support 21, and a groove 21a is formed in the first support 21 to communicate the hollow 22a of the second support 22 with the inside of the second container 5. Further, O-rings 23 and 24 are inserted between the first support body 21 and the outer wall of the second container 5, and between the second support body 22 and the partition wall 4, respectively. 2
The container 5 is hermetically sealed. With this configuration, if the capillary 9 becomes clogged, the capillary 9 can be removed together with the second support 22 by rotating the first support 21 and removing it from the opening 5a of the second container 5. Since it can be taken out, the capillary can be easily replaced with a new one. Note that this invention can be implemented with various modifications; for example, in the above embodiment, the support body that supports the leak member has a two-part structure, but it may of course be a single component; The body may be formed from the leak member to the body.

Furthermore, it goes without saying that the present invention can be applied in the same way even when a leak member having another structure such as a porous material is used in place of the capillary.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a sample introduction device of a conventional mass spectrometer, FIG. 2 is a sectional view of a sample introduction device of a mass spectrometer according to an embodiment of the present invention, and FIG. 3 is a main part of FIG. 2. It is a perspective view taken out and shown. 1...Sample introduction tube, 2...1st
container (sampling chamber), 3... Sample introduction port, 4... Partition wall, 5... Second container (valve box), 6...・Sample outlet, 7...
・Mass spectrometer body, 8...Ionization chamber, 9...
...Capillary (leak member), 10...
Valve mechanism, 21, 22... Support body, 21a,
22a...Communication part, 23, 24...0
ring.

Claims (1)

[Claims] 1 A first container having a sample inlet, a second container integrally formed with the first container via a partition wall and having a sample outlet communicating with the mass spectrometer main body, and these first and second containers. a leak member provided through the partition wall so as to communicate the second container with the second container, and an inlet side opening surface of the leak member on the first container side to control the inflow of the sample into the mass spectrometer main body. In the sample introduction device for a mass spectrometer, the second container is provided with an opening at a position facing the partition, the leak member is supported in the opening, and the outlet side of the leak member is supported in the opening. 1. A sample introduction device for a mass spectrometer, characterized in that a support body having a communication portion that communicates between an opening surface and a second container is detachably attached to the support body so as to airtightly seal the opening portion.