JP2000009610A - Sampling device of gas analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily replace a filter. SOLUTION: A sample gas flow channel 1 supplying a sample gas G, the three-way valve 16 provided to the sample gas flow channel 1 to open and close the sample gas flow channel 1 and the filter 4 provided on the downstream side of the three-way valve 16 of the sample gas flow channel 1 are provided to a gas analyzer 8 and, when the filter 4 is replaced, the analytical side of the filter 4 is opened to the atmosphere by the three-way valve 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas analyzer in which a filter for removing oil from a sample gas is provided in a sample gas flow path connected to, for example, an exhaust gas recirculation (EGR) type engine. (Hereinafter simply referred to as a sampling device).

[0002]

2. Description of the Related Art FIG.
It has a configuration shown in FIG. In the figure, reference numeral 1 denotes a sample gas flow path in which a sample gas point 2 is connected to an intake pipe of an exhaust gas recirculation type engine, and 3 denotes a normally open manual two-way valve provided on the upstream side of the flow path 1. Yes, the flow path 1 is manually opened and closed. Reference numeral 4 denotes a filter provided on the downstream side of the flow path 1 for removing oil of the sample gas G introduced into the flow path 1 from the sample gas point 2. Reference numerals 5, 6, 7 and 8 denote a normally closed two-way solenoid valve, a pressure regulator, a suction pump and a gas analyzer which are sequentially provided on the downstream side of the filter 4. The two-way solenoid valve 5 controls the flow of the sample gas G. The standby state is established by preventing the inflow to the road 1.

[0003] Reference numeral 9 denotes a purge air introduction passage connected to the flow path 1 between the two-way solenoid valve 5 and the pressure regulator 6, to which a filter 11 is connected via a normally-closed two-way solenoid valve 10; At the time of measurement,
The two-way solenoid valve 10 is turned on, the purge air purified by the filter 11 is introduced into the flow path 1, and the inside of the flow path 1 is cleaned. Reference numeral 12 denotes an open-to-atmosphere channel connected to the channel 1 between the pressure regulator 6 and the suction pump 7, and the three-way solenoid valve 1
The filter 14 is connected via 3. That is,
The first port 13a of the three-way solenoid valve 13 is
The second port 13b is connected to the filter 14, the third port 13c is connected to the closed channel 15, and when the suction pump 7 is stopped, the analysis side of the channel 1 is returned from the negative pressure state to the atmospheric state. .

Next, the operation will be described. First, the sample gas G flows from the sample gas point 2 of the flow path 1 through the two-way valve 3 and the filter 4 to the stage before the two-way solenoid valve 5, and is in a standby state. In this state,
The solenoid valves 5, 10, 13 and the pressure regulator 6 are off, and the suction pump 7 is stopped.

Next, when the suction pump 7 is driven from the above state and the two-way solenoid valve 5 and the pressure regulator 6 are turned on, the sample gas G flows in the flow path 1 toward the gas analyzer 8. On this occasion,
For example, -400 mmHg to -500 mm by the pressure regulator 6
The pressure is adjusted to Hg, and a sample gas G having a constant flow rate is introduced into the gas analyzer 8 by the suction pump 7, and the gas analyzer 8 measures the sample gas G.

After completion of the measurement, the three-way solenoid valve 13 is turned on, the first port 13a and the second port 13b are connected, the open-to-atmosphere flow path 12 is opened, and the analysis side of the flow path 1 in the negative pressure state is set to the atmospheric state. Return to Then, the state is shifted to the purge mode with the suction pump 7 turned on, and the two-way solenoid valve 5 is turned off, while the two-way solenoid valve 10 is turned on, air is introduced from the purge air introduction passage 9, and Clean inside. When replacing the filter 4 for removing the oil of the sample gas G, the two-way valve 3 is turned off.

[0007]

In the case of the conventional sampling device, when the filter 4 is replaced, the two-way valve 3 is required.
Is turned off, but -500 m is provided in front of the two-way valve 3.
Because a negative pressure of mHg to -600 mmHg is applied,
Even if the two-way valve 3 is turned off, the negative pressure is applied to the subsequent stage of the two-way valve 3, that is, the analysis side of the sample gas flow path 1, and it is difficult to replace the filter 4. is there.

[0008] The present invention has been made in view of the above, and an object of the present invention is to provide a sampling apparatus for a gas analyzer in which a filter can be easily replaced.

[0009]

In order to achieve the above object, a sampling apparatus for a gas analyzer according to claim 1 of the present invention comprises a sample gas flow path for supplying a sample gas to the gas analyzer; Provided in the sample gas flow path,
A three-way valve for opening and closing the sample gas flow path, and a filter provided downstream of the three-way valve in the sample gas flow path, and when replacing the filter, the three-way valve changes the analysis side of the filter. It is open to the atmosphere.

Therefore, when the filter is replaced, the analysis side of the sample gas flow path is opened to the atmosphere, so that the filter can be easily replaced.

Further, the present invention can be applied to a sample gas flow path connected to an exhaust gas recirculation type engine.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment will be described with reference to FIG. 4, the same reference numerals as those in FIG. 4 denote the same or corresponding components, and the difference is that a three-way valve 16 is connected to the sample gas flow path 1 instead of the two-way valve 3. That is, the first port 1 of the three-way valve 16
6a is connected to the sample gas point 2, the second port 16b is connected to the filter 4, and the third port 16c is connected to the open-to-atmosphere channel 17.

In the standby state, the first and second ports 16a and 16b of the three-way valve 16 communicate with each other, the sample gas G is introduced from the sample gas point 2, and the first and third ports are replaced when the filter 4 is replaced. Port 1
6a and 16c communicate with each other, and the analysis side of the flow path 1 is connected to the open-to-atmosphere flow path 17 to return from the negative pressure state to the atmospheric state. Further, since the analysis side of the flow path 1 is open to the atmosphere, the filter 4 can be replaced even during the measurement.

Next, the configuration of the filter 4 will be described with reference to FIG. In the figure, reference numeral 18 denotes a tubular body having a bottomed cylindrical state. A gas introduction portion 20 having a gas introduction hole 19 formed therein is provided at one end, and a gas outlet 21 is internally provided at the other end. A formed gas outlet 22 is provided,
The second port 16b of the three-way valve 16 is connected to the gas introduction unit 20, and the analysis side of the gas flow path 1 is connected to the gas outlet unit 22.

Reference numeral 23 denotes a cap, and 24 denotes a support having two O-rings 25 fitted on its peripheral surface.
3, a mounting portion 26 is formed to be removably mounted, and a support portion 27 is formed at a distal end portion. The support 24 has a communication hole 24 a penetrating the peripheral surface of the support 24, and the communication hole 24 a communicates with the communication hole 27 a of the support 27. 28 is a paper tube into which the filter material 29 has been inserted,
Reference numerals 30 denote sealing members attached to both ends of the paper tube 28, respectively. A through hole 31 is formed at the bottom, and the supporting portion 27 of the support 24 is inserted through the through hole 31 of one of the sealing members 30. Are supported by the support portion 27.

Then, the filter unit 32 in which the cap 23, the support 24, the sealing member 30, the paper tube 28 and the sealing member 30 are assembled is inserted into the tube 18, and the cap 23 is screwed to one end of the tube 18. Then, the cap 23 is attached to the tube 18. At this time, the communication hole 24a of the support 24 communicates with the gas introduction hole 19 of the tube 18, and the O-ring 25 and the seal member 30 of the support 24 are pressed against the inner surface of the tube 18 to be sealed.

Then, the sample gas G introduced from the gas introduction hole 19 is supplied to the communication hole 24 a and the communication hole 27 of the support 24.
After passing through the filter 4, the sample gas G is removed from the gas outlet 21 by the filter 4. When replacing the filter 4, the cap 23 is removed from the tube 18, the filter unit 32 is pulled out, the paper tube 28 is removed from the support 24, and the filter material 2 is removed.
9 is exchanged.

In the above embodiment, a three-way solenoid valve may be used in place of the manual three-way valve 16, but the manual three-way valve is lower in cost and more durable than the three-way solenoid valve. ing.

As shown in FIG. 3, two two-way valves 33 and 34 may be used in combination. The "three-way valve" in the present specification includes such a case. It is a concept. In this case, normally, the sample gas G is introduced by opening the two-way valve 33 connected to the flow path 1 and closing the two-way valve 34 connected to the open-to-atmosphere flow path 17.
When the filter 4 is replaced, the two-way valve 33 is closed and the two-way valve 34 is opened to open the analysis side of the flow path 1 to the atmosphere.

[0020]

As described above, in the gas analyzer sampling apparatus of the present invention, when the filter is replaced, the analysis side of the sample gas flow path is opened to the atmosphere by the three-way valve provided in the sample gas flow path. As a result, the filter can be easily replaced.

The present invention can also be applied to a sample gas flow path connected to an exhaust gas recirculation type engine.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of one embodiment of the present invention.

FIG. 2 is an exploded perspective view of the filter of FIG.

FIG. 3 is a schematic diagram of another embodiment of the present invention.

FIG. 4 is a schematic view of a conventional example.

[Explanation of symbols]

1: Sample gas flow path, 2: Sample gas point, 4
... Filter, 8 ... Gas analyzer, 16 ... Three-way valve, G ...
Sample gas.

Claims (2)

[Claims] A sample gas flow path for supplying a sample gas to a gas analyzer; a three-way valve provided in the sample gas flow path for opening and closing the sample gas flow path; A sampling device for a gas analyzer, comprising: a filter provided downstream of a three-way valve, wherein when the filter is replaced, the analysis side of the filter is opened to the atmosphere by the three-way valve. 2. The sampling device for a gas analyzer according to claim 1, wherein the sampling device is applied to a sample gas flow path connected to an exhaust gas recirculation type engine.