JPS6140341B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a detector for a device that performs gas analysis by utilizing the thermal conductivity of a gas to be measured, and more specifically to a semi-diffuse type detector that is optimal as a detector for a high-speed gas chromatograph. The present invention relates to a thermal conductivity type detector.

FIG. 1 is an explanatory diagram of the configuration of a semi-diffusion type thermal conductivity type detector of a conventional gas chromatograph. The detector consists of fillaments 28 and 29 installed in measurement chambers (chambers filled with measurement gas) 26 and 27 formed in a metal block 25, and a reference chamber (chamber filled with carrier gas) having the same structure. A Wheatstone bridge is constructed with a fillament (not shown) installed inside the tube.

By the way, it is desirable for such a detector to be as small as possible, that is, the internal volume of the measurement chambers 26 and 27 is as small as possible, since responsiveness can be improved. However, fillaments 28 and 29
In reality, if an attempt is made to have a predetermined resistance value, the shape becomes large, and the internal volume of the measurement chamber inevitably becomes large. In addition, since the filaments 28 and 29 are installed at the measurement points 26 and 27 formed by the metal block 25,
The problem was that it was difficult to replace the wire when it broke, and sometimes the entire detector had to be replaced, increasing maintenance costs.

The present invention has been made in view of these points, and the present invention reduces the internal volume of the measurement chamber, and
In order to facilitate the replacement of the filament, a through hole is formed in the plate surface, and the detector is constructed using a substrate having a resistor formed by forming a bridge in the through hole. .

Hereinafter, the present invention will be explained in detail with reference to the drawings.

2 to 4 are explanatory diagrams of the configuration of a gas chromatograph detector according to an embodiment of the present invention,
2 is a perspective view of the substrate 1, FIG. 3 is a sectional view taken along line AA in FIG. 2, and FIG. 4 is a longitudinal sectional view of the detector. In FIGS. 2 and 3, a substrate 1 has through holes 2, 3, 4, and 5 formed on its plate surface,
It has comb-tooth-shaped resistance antibodies 6 and 7 installed in a bridging manner in the through holes 3 and 5, respectively. And the respective ends 8 and 9 and 10 and 1 of the resistors 6 and 7
1 can be connected to other resistors or circuits at the end of the substrate 1.

Next, a detector constructed using the above substrate 1 will be explained with reference to FIG. 4.

The detector has two substrates 1 and a spacer 12 (without a resistor) having a shape substantially congruent with the substrate 1, that is, through holes 13, 14, 15, and 16 formed in the plate surface. , through holes 2 and 13, 3 and 14, 4 and 1
5, 5 and 16 are aligned and integrated, and the resistor elements 6 and 7 constitute a Wheatstone bridge, and a sensor block is provided on the plate surface at positions corresponding to the through holes 4 and 5, respectively. A side plate 17 has through holes 19 and 20 formed therein, and a flow path 18 that communicates with the through holes 2, 3, and 19, respectively, formed on the surface to be joined to the sensor block; A side plate 21 has through holes 22 and 24 formed at positions corresponding to the sensor block 5, and a flow path 23 communicating with the through holes 3, 4 and 22, respectively, on the surface to be joined to the sensor block. and a power source (not shown) that supplies power to the Wheatstone Bridge.

Incidentally, the sensor block and the side plate are integrated using known means such as adhesives, bolts and nuts (in this case, it is necessary to provide holes in the plate surface for the bolts to pass through).

The above detector includes a flow path formed by through hole 19 → flow path 18 → through hole 2 → through hole 13 → through hole 2 → through hole 22, and through hole 19 → through hole 4 → through hole 15
→Through hole 4→Flow path 23→While flowing the gas to be measured Fm through the flow path formed by the through hole 22, the measurement chamber formed by the through holes 3 and 14 is filled with the gas to be measured, and the through holes 5, 16, A carrier gas Fr is caused to flow into the reference chamber formed by 20 and 24, which functions as a detector for the gas chromatograph.

In this way, since the sensor block's measurement chamber is constituted by the through holes 3 and 14 formed in the plate surfaces of the substrate 1 and the spacer 12, the internal volume of the measurement chamber can be reduced. Also, bolt
A detector integrated using a nut can be easily disassembled, making it easy to replace the resistor and board, and is excellent in maintainability.

Although the above embodiment describes a gas chromatograph detector, the present invention is not limited to this, and may be applied to other analyzers such as an H ₂ meter,
It may be a detector such as an O ₂ meter or a CO ₂ meter.

Further, in the above embodiment, two substrates are integrated with a spacer interposed therebetween, but the present invention does not necessarily require a spacer. Integrate the two boards by aligning the board surfaces where no resistors are installed,
A measurement chamber and a reference chamber may be formed.

Furthermore, the side plates 17 and 21 are not limited to the above embodiments. In short, it is sufficient that the side plate 17 is connected to the through hole 4 on one side of the sensor block and forms a flow path connected to the through holes 2 and 3, and the side plate 21 is connected to the through hole 4 on one side of the sensor block. It is only necessary to configure a flow path that connects to the through hole 2 and communicates with the through holes 3 and 4.

Further, although the above embodiment uses a comb-like resistor, the present invention is not limited to this, and a spiral resistor may be used.

As explained in detail above, according to the thermal conductivity type detector of the present invention, the measurement chamber is configured with a substrate having a through hole formed in the plate surface and a resistor installed in the through hole in a bridging manner. Therefore, the internal volume of the measurement chamber can be reduced, and the resistor can be easily replaced.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the configuration of a conventional semi-diffusion type thermal conductivity detector, and FIG. 2 is an explanatory diagram of the configuration of an element (substrate) constituting a thermal conductivity detector according to an embodiment of the present invention. 3 is a sectional view taken along the line AA in FIG. 2, and FIG. 4 is an explanatory diagram of the configuration of a thermal conductivity meter detector according to an embodiment of the present invention. 1... Board, 2, 3, 4 and 5... Through hole, 6
and 7...resistor, 12...spacer, 17 and 21...side plate, 19, 20, 22 and 24...
Through holes, 18 and 23...channels.

Claims (1)

[Scope of Claims] 1. A resistor formed by forming first, second, third, and fourth through holes in a plate surface, and installing them in a bridging manner in each of the second and fourth through holes. A sensor comprising first and second substrates having the same number, through-holes having the same number in the first and second substrates are aligned and integrated, and each of the resistors constitutes a Wheatstone bridge. On one side of the block, the third
A first flow path connected to the through hole of the substrate and communicating with the first and second through holes, and a first flow path connected to the first through hole of the substrate on the other surface of the sensor block. a second flow path communicating with the second and third through holes, and a power supply applied to the Wheatstone bridge;
A measurement gas is caused to flow into the flow path or in the opposite direction thereof, and a reference gas is caused to flow or is contained in a chamber including the fourth through hole, and the output of the Wheatstone bridge is used as a measurement signal. A thermal conductivity type detector featuring: 2. A measuring gas inlet and a reference gas inlet are formed by penetrating the substrate at positions corresponding to the first and fourth through holes, respectively, and the second and third through holes of the substrate are formed on the surface to be joined to the sensor block. The first flow path is formed by joining and fixing a side plate to the other surface of the sensor block to form a through hole and a flow path communicating with the measurement gas inlet, respectively. The thermal conductivity type detector according to item 1. 3. A measuring gas inlet and a reference gas inlet are formed by penetrating the substrate at positions corresponding to the third and fourth through holes, respectively, and the first and second through holes of the substrate are formed on the surface to be joined to the sensor block. The second flow path is formed by joining and fixing a side plate to one surface of the sensor block to form a through hole and a flow path communicating with each of the measurement gas inlets. The thermal conductivity type detector according to item 1.