JP3299399B2 - Soil sample sampling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for collecting samples in which the formation is not disturbed (various samples constituting the ground). More specifically, the present invention relates to an apparatus having a core pressing piston inside an inner tube, The present invention relates to a sampling device that excavates a ground by rotating an outer tube by a rotating force of an inner tube rod by a planetary gear mechanism with respect to an inner tube connected to an outer tube rod that transmits an input.

[0002]

2. Description of the Related Art When investigating the properties of the ground, the most important task is to observe the ground. Then, samples of the ground are collected as little as possible and subjected to various laboratory tests. is there. The most common method of sampling is to drop a sampler into a borehole and collect a columnar sample (core sample) of any length (usually about 1 m) from the bottom of the hole. In the related art, a method has been adopted in which a single boring rod is used and a sample of the ground under the hole bottom is collected by rotating and pushing the boring rod. The main samplers include a Denison sampler, a triple tube sampler, and a core pack tube sampler, depending on the hardness of the ground.

[0003] As described above, all of these samplers are of a type in which a sampler is connected to one rod, and simultaneously rotated while pushing the rod, thereby inserting the sampler into the ground. The outer tube (core tube) fixed to the rod and the inner tube, which is connected to the rod via a bearing and has a structure that allows free rotation in the outer tube, are generally used. It is a target. Here, the outer tube is rotated, and at the same time, the inner tube is pushed in, and a ground sample is taken while expecting that the inner tube does not rotate.

[0004]

The biggest drawback of collecting a sample by such a method is that the inner tube is not removed due to carelessness of the boring operation or, for some reason, it cannot be avoided. That is, they rotate together with the tube (co-rotate). As a result, the sample taken into the inner tube is significantly disturbed, and in some cases, the sample does not enter the inner tube. Due to such mechanical drawbacks, it has been often experienced that it is difficult to collect a reliable sample. Further, for such a reason, the collection of a sample that does not disturb the ground requires the skill of a boring technician.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a soil sample sampling apparatus capable of improving core sampling quality by preventing the core sample from rotating during boring and not allowing stress release of the core sample. It is to provide.

[0006]

The present invention comprises an outer pipe rod for transmitting a press input and an inner pipe rod for transmitting a rotational force, wherein the inner pipe rod is rotatable with respect to the outer pipe rod. A double tube rod, an inner tube coupled to the lower end of the outer tube rod and containing a ground sample, and located outside the inner tube and having a cutting bit (eg, a metal crown) at the lower end to be rotatable. An outer tube, a core pressing piston slidable in the axial direction inside the inner tube,
A sun gear provided on the outer periphery of the lower end of the inner tube rod, a ring gear provided on the inner periphery of the outer tube, and a planetary gear rotatably held by the outer tube rod and meshing with the sun gear and the ring gear; And a planetary gear mechanism comprising:

Here, it is preferable that the core pressing piston has a rubber ring on its outer peripheral surface that is in sliding contact with the inner surface of the inner tube, and that the frictional force can be adjusted by changing the outward bulging amount of the rubber ring. Further, it is desirable to provide a structure in which a key mechanism and a spring are provided between the lower end of the outer tube rod and the upper portion of the inner tube, and a vibration / impact mitigation mechanism that allows only axial displacement is provided.

A plurality of outer pipe rods and inner pipe rods are sequentially connected by a joint part also serving as a centrizer in a boring hole, and the upper end is connected to a rotary boring machine via a swivel. The joint is such that a square hole at one end of the other inner tube rod is fitted into a square tube portion at one end of one inner tube rod, and the outer tube rod is connected by connecting screws at both ends of the outer tube portion. In addition, the swivel couples the inner pipe rod and the boring machine by fitting the outer pipe part, which is fitted into the vertical groove of the guide pipe at the boring hole opening to prevent rotation, and the square tube part and the square hole part. The structure has an inner tube part.

[0009]

The inner tube is connected to the outer tube rod so as not to rotate, while the outer tube is rotated by a planetary gear mechanism comprising a sun gear, a planetary gear and a ring gear of the inner tube rod. As a result, the pressurized force is transmitted to the inner tube and the rotational force is transmitted to the outer tube independently, so that the ground sample can be collected at the bottom of the borehole without boring the core sample during boring. A core pressing piston slidable in the axial direction is provided in the inner tube, and the stress of the sample is not released because the piston keeps pressing the surface of the ground sample during boring.

[0010] The joint part also serving as a centrizer,
The present invention improves the quality of sampling by minimizing the rotational vibration of the sampling device during boring, and facilitates the sequential connection of a plurality of outer pipe rods and inner pipe rods.
Swivels serve to convert a single rod into a double rod in a boring machine.

[0011]

FIG. 1 is an explanatory diagram showing the overall configuration of a sampling device according to the present invention. The whole apparatus is composed of a rotary boring machine 10 installed on the ground surface and a boring hole 12
Sampler 14, a double tube rod 16 suspending the sampler 14, a centrifuge / coupler unit 18 for holding the double tube rod 16 at the center of the hole, and a boring machine 10 located at the upper end of the double tube rod 16. Swivel 20 combined with
And a guide tube 21 and the like.

FIG. 2 shows an embodiment of a sampler 14 which is a main part of the sampling apparatus according to the present invention. The double tube rod 16 is composed of an outer tube rod 22 for transmitting a press input and an inner tube rod 24 for transmitting a rotational force.
2, the inner pipe rod 24 has a clearance and is rotatable. For example, 28mm for 50mmφ outer tube rod
Pass the inner tube rod of φ to assemble a 28-50 mm double tube rod. An inner tube 26 is connected to a lower end of the outer tube rod 22, and an outer tube 28 is located outside the inner tube 26. At the lower end of the outer tube 28 is a metal crown 2
9 are provided. A planetary gear mechanism 30 is provided between the inner tube rod 24 and the outer tube 28, and a core pressing piston 32 is provided below the inner tube 26.

As shown in FIG. 3, the planetary gear mechanism 30 includes a sun gear 34 provided on the outer periphery of the lower end of the inner tube rod 24 and a ring gear 36 provided on the inner periphery of the outer tube 28.
And three planetary gears 3 rotatably held by the outer tube rod 22 and meshing with the sun gear 34 and the ring gear 36.
8 For example, the inner pipe rod 24 rotates clockwise (arrow a).
Then, the sun gear 34 rotates, and the rotation is transmitted to the ring gear 36 via the planetary gear 38, and the outer tube 28 rotates left (indicated by an arrow b).

The core pressing piston 32 has a piston head 40, a rubber ring 42 fitted on the outer periphery thereof, and a sleeve portion 44 for pressing the rubber ring 42 in the axial direction to adjust the amount of expansion in the outer peripheral direction. , An adjusting screw 48 for adjusting the distance between the piston head 40 and the piston foot 46, and a pressing rubber 50 provided on the lower surface of the piston foot 46. Adjustment screw 48
When tightened, the distance between the piston head 40 and the piston foot 46 is reduced, and the rubber ring 42 is pressed down in the axial direction by the sleeve portion 44, so that the rubber ring 42 expands outward and The contact state changes (frictional force increases). Thereby, the sliding resistance of the core pressing piston 32 against the inner tube 26 can be adjusted. FIG. 4 shows a state inside the inner tube 26.
4A, and the appearance of the core pressing piston 32 is shown in FIG. When the adjustment screw is tightened, the rubber ring expands outward. The adjustment of the frictional force of the rubber ring 42 is set by, for example, torque driver control.

This core pressing piston 32 prevents the sample on the ground at the bottom of the hole from expanding due to the release of stress during the sampling operation, and at the same time, stops the head of the sample from swaying and minimizes the disturbance of the core due to the rotation of the hole. Fulfills the function of The core pressing force is adjusted to be (0.5 to 1.0) σ ' _V0 when the effective vertical earth covering pressure at the sampling depth is σ' _V0 .

As shown in FIG. 5, a key groove 52 extending in the vertical direction is provided at the lower end of the outer tube rod 22, and a vertical key 56 is provided on the outer peripheral surface of the upper end rod portion 54 of the inner tube 26. In addition to being combined so as to be relatively displaceable in the vertical direction but not rotating, a coil spring 58 is provided in the lower portion of the outer tube rod 22 to provide a vibration / impact mitigation mechanism that does not directly transmit vibration or impact. In addition, an air vent 62 is provided in the lid portion 60 above the inner tube 26, and a check valve 64 is incorporated in the air vent 62. This facilitates the storage of the sample by bleeding the air inside the inner tube 26 at the time of sampling, and also functions to prevent the stored sample from dropping after sampling. As shown in FIG. 2, a folded core pack tube 66 is provided between the core pressing piston 32 and the inner tube 26.

As shown in FIG. 5A, when the pressing rubber 50 at the tip of the core pressing piston 32 is pressed against the ground surface at the bottom of the boring hole, and the outer pipe rod 22 is press-fitted so as not to rotate, The inner tube 26 is also held without rotating. When the inner pipe rod 24 is rotated in this state, the outer tube 28 is rotated by the planetary gear mechanism 30, and the ground is dug by the metal crown 29 at the lower end. At this time, muddy water is supplied from the inner pipe rod 24 as shown by an arrow c. The muddy water flows out of the hole 59 and is supplied to the digging portion through the space between the inner tube 26 and the outer tube 28. Then, as shown in FIG. 5B, the ground sample (core sample) 61 is stored in the inner tube 26 while being pressed by the core pressing piston 32, and at the same time, the outer periphery of the ground sample 61 is It will be covered. In this way, the ground sample can be accommodated in the inner tube 26 without being absolutely rotated.

A plurality of outer pipe rods and inner pipe rods are sequentially connected in a boring hole by a joint part 18 also serving as a centrifuge, and the upper end is connected to a rotary boring machine 10 via a swivel 20. FIG. 6 shows details of the joint portion 18, and FIG. 7 shows details of the swivel 20. The upper end portion of the lower inner pipe rod joined by the joint portion 18 is formed in a square tubular shape, and the square tubular portion 70
The rotation is transmitted in such a manner that the square hole 72 at the lower end of the upper inner tube rod is fitted to the upper portion. The upper inner pipe rod is rotatable with respect to the outer cylinder 76 by a bearing 74. The upper and lower ends of the outer cylindrical portion 76 are screwed to an outer tube rod as a screw structure 78. Although not shown, a centrifugal mechanism that expands outward by a leaf spring type or a pantograph type is provided on the outside of the outer cylindrical portion 76 to prevent the deflection of the inner pipe rod and load the inner pipe rod. It functions to support the outside and prevent it from being transmitted to the sampler below. The swivel 16 includes an outer tube portion 82 in which the guide tube hooking portions 80 are fitted into a plurality of vertical grooves 79 of the guide tube 21 provided in the bore hole opening to prevent rotation, a square tube portion and a square hole portion. An inner tube portion for connecting the inner tube rod and the boring machine by fitting; the inner tube portion is rotatable with respect to the outer tube portion by a bearing 86;
Muddy water can be injected through it. The swivel 20 converts the single tube rod 11 of the boring machine 10 into a double tube rod 16 and supports rotation of the inner tube rod 24 but not rotation of the outer tube rod 22. In this way, when the rotary press-fitting is performed by the boring machine, the press-fitting force is transmitted to the outer pipe rod and the rotational force is separately transmitted to the inner pipe rod.

FIG. 8 shows a preparation process for collecting a ground sample in order. A guide tube 21 is attached to the opening of the boring hole 12 formed in the ground (A). Then, the sampler 14 is dropped down (B), and the centrizer and coupler unit 1 are removed.
The inner tube rod 24 and the outer tube rod 22 are connected via the cable 8 (C and D). A plurality of inner pipe rods and outer pipe rods are added together by a sent riser / coupler so that the sampler reaches the bottom of the hole. Then, the swivel 20 is attached to the uppermost portion (E), and the swivel 20 is inserted into the guide tube 21 so as not to rotate, and is connected to the boring machine 10 (F). From this state, while supplying muddy water, the boring machine 10 is driven to collect a ground sample from the bottom of the boring hole.

[0020]

According to the present invention, as described above, the inner tube is supported by the outer tube rod for transmitting the pressurized force, and the rotation of the inner tube rod is transmitted to the outer tube by the planetary gear mechanism. However, it is ensured that the inner tube never rotates even if the outer tube rotates during sampling. In addition, since the inner tube has a built-in core pressing piston having an appropriate frictional force, the ground at the bottom of the hole being collected is continuously pressed with a predetermined force, so that it is possible to prevent the ground from falling apart. Therefore, a sample with little disturbance can be collected. Ground samples with elements with different hardness can be reliably collected. The sampling operation does not particularly require the skill of a boring technician. And so on. Then, more reliable sampling can be performed for a ground wider than the conventional sampling device, and in some cases, a sample can be collected in the same orientation as the ground is.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a sampling device according to the present invention.

FIG. 2 is a sectional view showing one embodiment of a sampler.

FIG. 3 is an explanatory diagram of a planetary gear mechanism.

FIG. 4 is an explanatory view of a core pressing piston.

FIG. 5 is an explanatory diagram of the operation of the sampler.

FIG. 6 is a cross-sectional view of a sent riser / coupler unit.

FIG. 7 is a sectional view of a swivel.

FIG. 8 is an explanatory diagram showing a preparation process of a sampling operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Boring machine 12 Boring hole 14 Sampler 16 Double tube rod 18 Centrifizer and coupler part 20 Swivel 21 Guide tube 22 Outer tube rod 24 Inner tube rod 26 Inner tube 28 Outer tube 29 Metal crown 30 Planetary gear mechanism 32 Core pressing piston 34 Sun gear 36 Ring gear 38 Planetary gear 42 Rubber ring 48 Adjustment screw

Claims (4)

(57) [Claims] 1. A double pipe rod comprising an outer pipe rod for transmitting a press input, and an inner pipe rod for transmitting a rotational force, wherein the inner pipe rod is rotatable with respect to the outer pipe rod. An inner tube coupled to the lower end of the outer tube rod and containing a ground sample; a rotatable outer tube located outside the inner tube and having a cutting bit at the lower end; and an axial direction inside the inner tube. A slidable core pressing piston, a sun gear provided on the outer periphery of a lower end of the inner tube rod, a ring gear provided on an inner periphery of the outer tube, and the sun gear rotatably held by the outer tube rod. And a planetary gear mechanism comprising a planetary gear meshing with the ring gear. 2. The sampling according to claim 1, wherein the core pressing piston has a rubber ring on its outer peripheral surface which is in sliding contact with the inner surface of the inner tube, and the amount of outward expansion of the rubber ring is variable to adjust the frictional force. apparatus. 3. The sampling apparatus according to claim 1, further comprising a key mechanism and a spring between the lower end of the outer tube rod and the upper portion of the inner tube, and a vibration / impact mitigation mechanism that allows only axial displacement. 4. A structure in which a plurality of outer pipe rods and inner pipe rods are sequentially connected in a boring hole by a joint part also serving as a centrifuge, and an upper end is connected to a rotary boring machine via a swivel. The joint is such that a square hole at one end of the other inner tube rod is fitted into a square tube portion at one end of one inner tube rod, and the outer tube rod is connected by connection screws at both ends of the outer tube portion. The swivel is an inner tube that connects the inner tube rod and the boring machine by fitting the outer tube portion that is fitted into the vertical groove of the guide tube at the borehole opening to prevent rotation, and the square tube portion and the square hole portion. The sampling device according to claim 1, further comprising a unit.