JPH0240529Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention mainly relates to a device for detecting fumigant gas, etc. remaining in soil.

When fumigation is carried out using a soil fumigation agent (for example, Dei Trapex Oil (trademark)), a sufficient control effect can be obtained over a wide range of harmful pests, pathogenic bacteria, etc. in the soil. However, when the above-mentioned soil fumigant is used, a considerable amount of gas remains in the soil, which may cause phytotoxicity to planted crops. Normally, the soil is tilled to eliminate residual gas in the soil, but it is necessary to check whether the gas has been sufficiently eliminated before planting plants. The present invention is a particularly effective device for detecting gas in soil in such cases.

Prior Art Conventionally, there was no means to easily and quickly detect fumigant gas remaining in soil. Therefore, in order to detect residual gas in the soil, it is necessary to collect local soil samples and subject them to instrumental analysis, or to conduct a germination test (cress test) using a specific seed (Cress test).
I had no choice but to rely on The above-mentioned "cress test" is a method of detecting residual gas in soil samples using the germination and extension of cress seeds as an indicator.
You need to wait for some time.

Purpose of the present invention The present invention aims to provide a device that can easily and quickly detect gas remaining in soil on-site.

Structure of the Present Invention The present invention includes a protection tube 10 having intake holes 14, 14 that can be opened and closed, a gas sensor 20 provided at a predetermined position above the intake hole position in the protection tube 10, and the protection tube 10. The air intake device 30 includes an air intake device 30 connected to an upper opening of the air conditioner.

Effect of the present invention In the device of the present invention, the protection tube is first inserted into the soil to be tested to a predetermined insertion depth (usually about 15 to 20 cm from the ground surface), and then the intake hole is opened and the gas in the soil is protected by the intake device. The gas to be detected can be detected by introducing the gas into the pipe and bringing the gas into contact with a gas sensor.

Embodiment of the present invention FIG. 1a is a perspective view showing an apparatus as an embodiment of the present invention, and FIG. 1b is an exploded perspective view of the apparatus of FIG. 1a. In FIG. 1a and FIG. 1b, the protective tube 10 has an inner tube 11 made of metal (for example, stainless steel).
is slidably and tightly fitted into an outer cylinder 12 made of the same material. A cap 13 is screwed onto the male threaded portion at the lower end of the inner cylinder 11. The cap 13 has a female thread cut on the inner circumferential surface and is shaped like an inverted cone toward the tip. Further, the outer peripheral surface of the inner cylinder 11 slightly above the cap 13 is provided with a predetermined interval (for example, the inner cylinder 1
Approximately circular intake holes 14, 14 are bored at intervals of 60° or 90° in the circumferential direction of one outer periphery. Inner cylinder 11
One guide pin 15 is provided at a predetermined position on the upper outer peripheral surface.
has been planted. Further, at a position above the guide pin 15 of the inner cylinder 11, a pair of left and right rod-shaped handles 1 are provided in a direction substantially perpendicular to the axial direction of the inner cylinder 11.
6 and 16 are provided.

On the other hand, the guide pin 1 of the inner cylinder 11 is attached to the outer cylinder 12.
A guide groove 17 is provided in which the guide groove 5 is slidably fitted. The guide groove 17 includes a horizontal groove portion 17a extending along the circumferential direction of the outer cylinder, and a vertical groove portion 17b continuing from one end of the horizontal groove portion and extending along the axial direction of the outer cylinder. When the guide pin 15 is fitted into the horizontal groove 17a, the lower end of the outer cylinder 12 is connected to the lower end of the inner cylinder 11 of the cap 1.
3, the intake holes 14, 14 are completely closed. Also, the guide pin 15 is connected to the vertical groove portion 1.
7b, the outer cylinder 12 can move in the vertical direction (axial direction) from the position where the intake holes 14, 14 are completely closed to the position where they are completely opened, as described above. A rubber, cork or metal cap 18 is fitted into the upper opening of the inner cylinder 11. Further, a known semiconductor gas sensor 20 (for example, TGS-812 and TGS-813 manufactured by Figaro Giken Co., Ltd.) is provided in the inner cylinder 11 at a position slightly higher than the intake hole 14. In this embodiment, the gas sensor 20 is
1 Lead wire 21 inserted into the upper cap 18
suspended by. A known intake pump 30 made of rubber and serving as an intake device is connected to the upper part of the inner cylinder 11. That is, the intake pipe 31 of the intake pump 30 is inserted into the cap 18 on the upper part of the inner cylinder 11,
It opens toward the inside of the inner cylinder 11.

As the suction pump 30, the inner cylinder 1 can be
It is convenient to use one with a capacity that can inhale gas equivalent to the internal volume of 1.

As shown in FIG. 1b, a scale 40 is provided on the outer peripheral surface of the outer cylinder 12 to indicate the insertion depth of the protection tube 10 into the soil.

Specifications of an embodiment of the device of the present invention having the above configuration are shown below.

Total length of inner cylinder 11 (including cap 13): 600mm
Inner diameter of inner cylinder 11: 18 mm Distance from the bottom end of cap 13 to the center of intake hole 14: 100 mm Arrangement and dimensions of intake hole 14: 4 locations at 90° intervals,
Diameter 6mm Gas sensor: TGS manufactured by Figaro Giken Co., Ltd.
−813 To measure residual gas in soil using the device of the present invention as described above, proceed as follows. First, the guide pin 15 of the inner cylinder 11 and the guide groove 1 of the outer cylinder 12
7 so that they fit together with the horizontal groove 17a. In this state, the intake holes 14, 14 of the inner cylinder 11 are connected to the outer cylinder 1.
2, and the inner cylinder 11
Changes in the relative positions of the outer cylinder 12 and the outer cylinder 12 in the axial direction are regulated by the lateral groove 17a and the guide pin 15 fitted therein.

Next, the protection tube 10 in the above-mentioned state is inserted into the soil. In this case, the insertion depth of the protective tube 10 can be determined using the scale 40 provided on the outer cylinder 12 as a guide. After inserting the protective tube 10 to a predetermined depth, the guide pin 15 moves the outer cylinder 12 into the guide groove 1.
7 until it fits into the vertical groove 17b.
Next, while keeping the inner cylinder 11 still, remove the outer cylinder 1.
2 in the axial direction. When the outer cylinder 12 is pulled up to a position where the guide pin 15 and the lower end of the vertical groove 17b of the guide groove 17 come into contact, the intake hole 1 of the inner cylinder 11
4 and 14 are completely opened.

Next, when the intake pump 30 is operated, the intake hole 1
Gas in the soil flows into the inner cylinder 11 through 4 and 14, and this gas comes into contact with the gas sensor 40. The gas that comes into contact with the gas sensor changes the electrical resistance of the sensor depending on its concentration. The presence of gas can thus be detected by a conventional display device (eg, a voltmeter) (not shown) to which the lead 21 of the gas sensor 20 is connected.

FIG. 2 is a perspective view showing another embodiment of the present invention. In FIG. 2, parts corresponding to those in FIGS. 1a and 1b are designated by the same reference numerals. In the lower part of the outer cylinder 12 in FIG.
Vent holes 14', 14' corresponding to holes 4, 14 are provided. In addition, the guide groove 17 is shown in FIG.
It consists only of horizontal grooves corresponding to the horizontal grooves 17a in FIG. b.

The method of detecting gas in soil using the device shown in FIG. 2 is almost the same as the devices shown in FIGS. By rotating the cylinder 12 in the circumferential direction, the positions of the intake holes 14', 14' of the outer cylinder 12 are changed to the positions of the intake holes 14, 1 of the inner cylinder.
This is done depending on whether or not it is aligned with position 4.

FIG. 3 is a perspective view showing another embodiment of the present invention. In FIG. 3, parts corresponding to those in FIGS. 1a and 1b are designated by the same reference numerals. The protective tube 10 in FIG. 3 includes a cylindrical body 11'' made of stainless steel, for example, which has an opening as an intake hole 14'' at the lower end, an inverted conical lid 13' that can seal the opening, and a lower end. The rod 50 is connected to the lid 13' and inserted through the cylindrical body 11' so that its upper end extends above the upper end of the cylindrical body 11'. A rod-shaped handle 51 is attached to the upper end of the rod 50 and is substantially perpendicular thereto.
The lid body 13' has a conical outer shape that is almost similar to the cap 13 at the lower end of the inner cylinder 11 in FIGS. A stepped portion 13'a is formed to fit shallowly into the lower opening of 11'.

When detecting gas in soil using the device shown in Figure 3, proceed as follows. First, by pulling the rod 50 upward relative to the cylindrical body 11', the lower opening (i.e., the intake hole) 14'' of the cylindrical body 11' is sealed with the lid 13'.
0 into the soil to a predetermined depth. Next, hold down the handle 51 of the rod 50 and remove the lid 13' at the lower end.
The cylindrical body 11' is pulled upward while keeping the position fixed. In this way, the opening (intake hole) 14'' at the bottom of the cylindrical body 11' opens, and by operating the intake pump 30, gas in the soil is removed from the intake hole 14''.
It becomes ready to be introduced into the cylindrical body 11' through the tube.
The subsequent operations are exactly the same as in the embodiment described with reference to FIGS. 1a and 1b.

In any of the embodiments described above, it is of course possible to use a portable electric pump as the intake device instead of the manual intake pump 30 made of rubber.

Effects of the present invention As described above, according to the present invention, gas remaining in the soil can be detected easily and quickly on-site. That is, not only is it not necessary to collect a sample of the soil to be tested, but the measurement itself can be performed quickly. Therefore, it is extremely effective to apply the device of the present invention when investigating the presence or absence of residual gas in the soil at a large number of locations over a large area of cultivated land. Furthermore, in the device of the present invention, the intake hole 14 for introducing the test gas can be closed while the protection tube 10 is inserted into the soil to a predetermined depth or extracted. The gas sensor 20 is less likely to be contaminated by soil intrusion. Further, if the device is as shown in FIGS. 1a to 3, it is easy to disassemble and maintain it.

[Brief explanation of the drawing]

FIG. 1a is a perspective view of an apparatus according to an embodiment of the present invention, FIG. 1b is an exploded perspective view of the apparatus of FIG. 1a, and FIGS. 2 and 3 are apparatuses according to other embodiments of the present invention. FIG. 10... Protection tube, 11... Inner tube, 11'... Cylindrical body, 12... Outer tube, 13... Cap, 13'
...Lid, 14, 14', 14''...Intake hole, 15
... Guide pin, 16 ... Handle, 17 ... Guide groove, 20 ... Gas sensor, 30 ... Intake pump, 40 ... Scale, 50 ... Rod.

Claims (1)

[Claims for Utility Model Registration] (1) A first protective tube portion having an intake hole in the lower portion;
a second protection tube section that is movable relative to the protection tube section and opens and closes the intake hole;
a protection tube whose lower end forms a closed end portion in the shape of an inverted cone; a gas sensor provided within the protection tube at a predetermined position above the intake hole position; and a gas sensor connected to an upper part of the space within the protection tube for ventilation. A soil gas detection device characterized in that it is equipped with an air intake device. (2) The protective tube has a hollow cylindrical inner cylinder whose lower end is closed in an inverted conical shape and an intake hole is bored on the lower peripheral surface thereof, and a hollow cylindrical inner cylinder whose lower end is open and which is slidably connected to the inner cylinder. It is composed of a hollow cylindrical outer cylinder that can be inserted into the cylinder,
The utility model registration claim 1, wherein the intake hole is configured to be openable and closable by changing the relative positions of the inner cylinder and the outer cylinder in the axial direction when the inner cylinder and the outer cylinder are fitted together. Soil gas detection device. (3) The protection tube has a hollow cylindrical inner cylinder whose lower end is closed in the shape of an inverted cone and an intake hole is bored on the lower circumferential surface, and a hollow cylindrical inner cylinder whose lower end is open and whose lower circumferential surface has the inner cylinder. A hollow cylindrical outer cylinder is provided with an intake hole corresponding to the intake hole, and the inner cylinder can be slidably and tightly fitted into the inner cylinder, and the intake hole of the inner cylinder is formed in a manner that the inner cylinder and the outer cylinder fit into each other. The soil gas detection device according to claim 1, which is a registered utility model and is configured to be openable and closable by changing the relative position in the circumferential direction with respect to the intake hole of the outer cylinder in the inserted state. (4) The protective tube is composed of a hollow cylindrical body having an opening as an intake hole at the lower end, and an inverted conical lid body that can arbitrarily open and close the opening by attaching and detaching the opening, and the lid body is operable by a rod-shaped body inserted into the cylindrical body such that its lower end is fixed to the lid body and its upper end extends above the upper end of the cylindrical body,
Utility model registration claim 1, wherein the opening of the cylindrical body is configured to be able to be opened and closed by attaching to and detaching from the lid body by changing the relative position of the cylindrical body and the rod-shaped body in the axial direction. The soil gas detection device described. (5) The gas detection in soil according to any one of claims 1 to 4 of the utility model registration claim, wherein the protection tube has a scale on its outer circumferential surface that indicates the depth of insertion into the soil. Device.