JP7629699B2 - Borehole photography device - Google Patents

Description

The present invention relates to a borehole imaging device that takes pictures inside a borehole.

To understand the geological conditions inside the hole during advanced drilling, a camera is inserted into the hole and video is taken to confirm the geology at each depth and the location of spring water. The camera is inserted into the hole after the drilling work is completed and all the hole retaining pipes and drilling rods have been removed, on the assumption that the hole wall will be self-supporting.

Therefore, when the borehole wall was not self-supporting or when there was a lot of slime in the borehole, it was difficult to insert the camera into the borehole or to take pictures due to materials adhering to the tip of the camera. Also, if the borehole wall collapsed during borehole observation, it became difficult to retrieve the camera, and the camera often had to be abandoned. Furthermore, the borehole wall often collapsed immediately after the rod was pulled out.

Therefore, a geological exploration method has been proposed in which an endoscope insertion section of an industrial endoscope device is inserted through a drilling water supply line from the mouth side of a rod equipped with a drilling bit at its tip, the tip of the rod protrudes to the outside from the drilling water discharge hole of the drilling bit, and the endoscope insertion section is used to explore the condition of the ground ahead of the drilling bit (see, for example, Patent Document 1).

JP 2016-130811 A

However, with conventional technology, when continuously exploring the condition of the ground inside a hole in the axial direction, the rod must be pulled out with a traction tool while simultaneously pulling out the endoscope insertion part, which is a cumbersome task. In addition, because the drilling rod is connected every specified length (e.g., 3 m), it is necessary to rotate and remove the drilling rod when pulling it out. Therefore, the cable connected to the endoscope insertion part must also be connected every specified length, which requires repeated cutting and reconnection when pulling it out.

The present invention was made in consideration of the above problems, and aims to solve the problem by providing an in-hole photography device that can easily take continuous axial images of the condition of the ground inside the hole by simply pulling out the drilling rod.

The borehole photography device of the present invention is an in-hole photography device that photographs the inside of a hole drilled by a drilling rod having a drilling bit attached to the tip of the rod, and comprises a capsule body that can be inserted into a hollow tube that connects from the hole mouth side to the tip of the drilling rod and opens at the tip of the drilling bit, and a fixing mechanism that fixes the capsule body transported toward the tip of the drilling rod by an air flow or water flow to the tip of the drilling rod, and the capsule body has a built-in camera that photographs the inside of the hole, a recorder that records the images captured by the camera, and a battery that supplies power to the camera and the recorder, and the device comprises a plurality of connected capsule bodies, the camera, the recorder and the battery are distributed and built into the plurality of capsule bodies, and the plurality of capsule bodies are connected via a damper member .
The borehole photography device of the present invention is an in-hole photography device for photographing the inside of a hole drilled by a drilling rod having a drilling bit attached to the tip of the rod, and comprises a capsule body that can be inserted into a hollow tube that communicates from the hole mouth side to the tip of the drilling rod and opens at the tip of the drilling bit, and a fixing mechanism that fixes the capsule body, which has been transported toward the tip of the drilling rod by an air flow or a water flow, to the tip of the drilling rod, and the capsule body has a built-in camera that photographs the inside of the hole, a recorder that records the images captured by the camera, and a battery that supplies power to the camera and the recorder, and is characterized in that a guide member that abuts against the inner surface of the hollow tube is attached as a guide mechanism for guiding the transport of the capsule body, and a cover member that urges the attached guide member in a radial direction is provided, and the guide member fits into a circumferential groove formed on the inner surface of the tip of the drilling rod, and the cover member is urged against the inner surface of the hollow tube, so that the guide mechanism functions as the fixing mechanism.
Furthermore, the borehole photography device of the present invention may comprise a plurality of connected capsule bodies, and the camera, the recorder and the battery may be distributed and built into the plurality of capsule bodies.
Furthermore, in the borehole imaging device of the present invention, the capsule bodies may be connected via a damper member .
Furthermore, in the borehole photography device of the present invention, when the capsule body is fixed to the tip of the borehole drilling rod by the fixing mechanism, the fixing mechanism may function as a shielding mechanism that blocks the air flow or water flow that transports the capsule body.

According to the present invention, the borehole photographing device, which is equipped with a camera, recorder, and battery, can be fixed to the tip of the borehole rod while it is being pulled out, which has the effect of easily and continuously photographing the condition of the ground inside the borehole in the axial direction simply by pulling out the borehole rod. In addition, the entire line can be photographed reliably without worrying about the borehole wall collapsing.

1 is a diagram showing the configuration of an embodiment of an in-hole imaging device according to the present invention; FIG. 2 is a diagram showing a configuration of the camera capsule shown in FIG. 1 during transportation. FIG. 2 is a diagram showing a configuration when the camera capsule shown in FIG. 1 is positioned; 4 is a diagram showing a configuration of a guide mechanism shown in FIG. 2 and FIG. 3 ; 4 is a diagram showing an example of a configuration in which a plurality of the guide mechanisms shown in FIGS. 2 and 3 are provided; FIG.

Next, a form for implementing the present invention (hereinafter simply referred to as "embodiment") will be specifically described with reference to the drawings.

As shown in FIG. 1(a), the borehole imaging device 1 of this embodiment is used to drill a hole using a drilling rod 4 with a drilling bit 3 attached to the tip of the rod 2. After boring, the rod 2 is inserted into a hollow tube 5 that connects to the tip of the drilling bit 3 inside the drilling rod 4, and is transported toward the tip of the drilling rod 4 by an air flow or water flow toward the tip. Note that, in this embodiment, the direction of drilling is described as horizontal, but there is no particular restriction on the direction of drilling.

Then, the transported borehole imaging device 1 is positioned and fixed by the circumferential groove 51 formed on the inner surface of the tip of the borehole drilling rod 4, as shown in FIG. 1(b). In this state, the borehole imaging device 1 is capable of imaging the inside of the borehole A, and by simply removing the borehole rod 4, it is possible to continuously image the condition of the ground inside the borehole A in the axial direction.

The hollow tube 5 may be connected from the mouth of the drilling rod 4 to the tip and open at the tip of the drilling bit 3. For example, it may be a drilling water supply pipe that supplies drilling water to the tip of the drilling bit 3, or, if the drilling rod 4 is a reverse circulation drill, an internal rod that discharges drilling chips to the outside. If the inner surface of the drilling rod 4 is smooth, it may be used as a substitute for the hollow tube 5. In addition, in Figures 1 and 2, for the purpose of explanation, the diameter of the hollow tube 5 is the maximum diameter that can fit inside the rod 2, but there is no limit to the diameter of the hollow tube 5 as long as the borehole photography device 1 can be inserted.

Referring to FIG. 1, the borehole photography device 1 is equipped with a light 11 that irradiates light into the borehole A, and has a camera capsule 10 with a built-in camera 12 that photographs the borehole A, a recording capsule 30a with a built-in recorder 31 that records the images captured by the camera 12, and a battery capsule 30b with a built-in battery 32 that supplies power to the light 11, the camera 12, and the recorder 31.

The camera capsule 10 and the recording capsule 30a are connected by a cable 40 for power and shooting data, and a damper member 50 such as a spring is provided to prevent collision between the camera capsule 10 and the recording capsule 30a. Similarly, the recording capsule 30a and the battery capsule 30b are connected by a cable 40 for power, and a damper member 50 such as a spring is provided to prevent collision between the recording capsule 30a and the battery capsule 30b. The dimensions of each component of the camera capsule 10, camera 12, etc. are selected according to the shape of the drilling rod 4 and hollow tube 4.

In this way, by configuring the borehole imaging device 1 by connecting multiple capsules, each capsule can be made small, and it is possible to transport it to the tip even if the hollow tube 5 is bent in the middle. If the diameter of the hollow tube 5 is large or there is no bent part, the camera capsule 10 may also include a recorder 31 and battery 32 built in, so that one capsule can handle it.

The borehole imaging device 1 is inserted into the hollow tube 5 with the camera capsule 10 at the front. Referring to Figures 2 and 3, the camera capsule 10 has a light 11 attached to the tip, a capsule body 13 with a built-in camera 12, and a guide mechanism 20 that contacts the inner surface of the hollow tube 5 to guide the transport of the camera capsule 10.

The camera 12 is composed of a CCD camera or a CMOS camera that can capture video or still images of the state inside the hole A. The camera 12 may be a borehole camera.

The capsule body 13 is a cylindrical body with a shooting port for the camera 12 formed at the tip, and in this embodiment, is formed into a cylindrical shape with a diameter smaller than the inner diameter of the hollow tube 5.

The guide mechanism 20 includes a pair of cover members 22 to which guide members 21, each of which is made of a roller that contacts the inner circumferential surface of the hollow tube 5, are attached. The cover members 22 are made of a resin such as rubber, and are arc-shaped in cross section with an outer circumferential surface that has the same curvature as the inner circumferential surface of the hollow tube 5.

The pair of cover members 22 are attached to the outer periphery of the capsule body 13 at axially symmetric positions so as to be movable in the radial direction along a guide member 14 erected on the outer periphery of the capsule body 13. The pair of cover members 22 are connected by a biasing member 23 such as a spring that biases the pair of cover members 22 in directions away from each other.

The guide member 21 is attached so that the contact portion with the inner peripheral surface of the hollow tube 5 protrudes from the outer peripheral surface of the cover member 22. Therefore, when the camera capsule 10 shown in FIG. 2 is transported, the guide member 21 is biased toward the inner peripheral surface of the hollow tube 5, and a gap X is formed between the inner peripheral surface of the hollow tube 5 and the outer peripheral surface of the cover member 22. This gap X becomes a passageway for the air or water current that transports the borehole imaging device 1.

The recording capsule 30a and the battery capsule 30b also have a capsule body 33 with a built-in recorder 31 and battery 32, respectively, and a guide member 34 consisting of a roller that contacts the inner peripheral surface of the hollow tube 5 is attached to the peripheral surface of the capsule body 33. As a result, the gap between the inner peripheral surface of the hollow tube 5 and the capsule body 33 also becomes a passageway for the air flow or water flow that transports the borehole imaging device 1. Therefore, the borehole imaging device 1, which is formed by connecting the camera capsule 10, the recording capsule 30a, and the battery capsule 30b, is transported at an appropriate speed by riding on the air flow or water flow.

As shown in FIG. 3, the camera capsule 10 is positioned with the guide member 21 fitted into the circumferential groove 51. The circumferential groove 51 is formed to a depth equal to or greater than the length of the guide member 21 protruding from the outer circumferential surface of the cover member 22. Therefore, when the guide member 21 is positioned in the circumferential groove 51, the outer circumferential surface of the cover member 22 is forced into contact with the inner circumferential surface of the hollow tube 5, and the guide mechanism 20 functions as a fixing mechanism, the camera capsule 10 is fixed to the tip of the drilling rod 4, and the gap X that could be a passageway for air or water flow is eliminated.

Although omitted in Figs. 2 and 3, referring to Fig. 4, a sheet member 15 for blocking air flow or water flow is provided between the circumferential surface of the capsule body 13 and the cover member 22 and at the connection portion of the pair of cover members 22. During transportation, the sheet member 15 is in a folded state as shown in Fig. 4(a). In the positioned state, the sheet member 15 is stretched between the circumferential surface of the capsule body 13 and the cover member 22 and at the connection portion of the pair of cover members 22 as shown in Figs. 4(b) to (d), thereby blocking air flow or water flow.

In other words, when the guide member 21 is positioned in the circumferential groove 51, the guide mechanism 20 functions as a mechanism for blocking air or water flow, preventing the air or water flow from escaping toward the tip of the drilling bit 3. This eliminates the propulsive force caused by the air or water flow, and the recording capsule 30a and battery capsule 30b following the camera capsule 10 also stop safely (without collision).

When the camera capsule 10 is positioned, the air pressure or water pressure at the hole mouth side of the drilling rod 4 increases. Therefore, it is a good idea to detect the increase in air pressure or water pressure and stop the air or water flow from being compressed, or to limit the air or water pressure so that it does not rise above a predetermined value.

The camera 12 may be inserted into the hollow tube 5 with the borehole imaging device 1 already in a state where imaging has begun, but it may also be configured to start imaging in a positioned state by providing a sensor that detects when the guide member 21 has fitted into the circumferential groove 51 (for example, a sensor that detects the separation of the cover member 22 from the capsule body 13).

In addition, when photographing in conjunction with the removal of the drilling rod 4, the camera capsule 10 fixed to the tip of the drilling rod 4 also rotates, but the orientation of the image can be corrected by performing image processing or by providing a gyro sensor that detects the angle of rotation.

The circumferential groove 51 is also formed with a gentler inclination at the rear end than at the front end. This allows the guide member 21 to be pulled out of the circumferential groove 51 by the air or water flow in the opposite direction, making it easy to retrieve the borehole imaging device 1.

As shown in FIG. 5, multiple guide mechanisms 20 may be provided on the circumferential surface of the capsule body 13, with the angle around the axis being changed. In this case, the transportation of the camera capsule 10 is stabilized, and the air flow or water flow can be blocked more reliably when the camera capsule 10 is positioned. The tip of the hollow tube 5 is formed with the same number of circumferential grooves 51 as the number of guide mechanisms 20, but the circumferential grooves 51 located on the tip side of the hollow tube 5 should be formed with a gentle slope on the tip side so that the preceding guide mechanism 20 can easily pass through.

As described above, this embodiment is an in-hole photography device 1 that photographs the inside of a hole A drilled by a drilling rod 4 having a drilling bit 3 attached to the tip of the rod 2, and is equipped with a capsule body that can be inserted into a hollow tube 5 that connects from the hole mouth side to the tip of the drilling rod 4 and opens at the tip of the drilling bit 3, and a fixing mechanism (guide function 20) that fixes the capsule body 13 transported toward the tip of the drilling rod 4 by an air flow or water flow to the tip of the drilling rod 4, and the capsule body 13 has a built-in camera 12 that photographs the inside of the hole, a recorder 31 that records the images captured by the camera 12, and a battery 32 that supplies power to the camera 12 and the recorder 31.
With this configuration, the borehole photographing device 1 equipped with the camera 12, recorder 31 and battery 32 can be pulled out while being fixed to the tip of the borehole rod 4, so that the condition of the natural ground inside the hole can be easily and continuously photographed in the axial direction simply by pulling out the borehole rod 4. Also, since there is no need for an electric wire to connect the borehole mouth side of the borehole rod 4 to the borehole photographing device 1, the operation of pulling out the borehole rod 4 can be performed smoothly.

Furthermore, in this embodiment, a plurality of linked capsule bodies 13, 33 are provided, and the camera 12, the recorder 31 and the battery 32 are built in and distributed among the plurality of capsule bodies 13, 33.
This configuration allows each capsule body 13, 33 to be made small, and even if the hollow tube 5 is bent midway, it becomes possible to transport the capsule body 13, 33 to the tip.

Furthermore, in this embodiment, the capsule bodies 13 and 33 are connected to each other via a damper member.
This configuration makes it possible to prevent the capsule bodies 13 and 33 from colliding with each other and being damaged.

Furthermore, in this embodiment, a guide member 21 abutting the inner surface of the hollow tube 5 is attached as a guide mechanism 20 for guiding the transportation of the capsule body 13, and a cover member 22 is provided for biasing the attached guide member 21 in the radial direction, and the guide member 21 fits into a circumferential groove 51 formed on the inner surface of the tip of the drilling rod 4, and the cover member 22 is biased to abut against the inner surface of the hollow tube 5, so that the guide mechanism 20 functions as a fixing mechanism.
With this configuration, the guide mechanism 20 can also be used as a fixing mechanism.

Furthermore, in this embodiment, when the capsule body 13 is fixed to the tip of the drilling rod 4 by the fixing mechanism, the fixing mechanism functions as a shielding mechanism that blocks the air flow or water flow that transports the capsule body 13.
This configuration allows for the stopping of transport by air or water currents.

The present invention has been described above based on an embodiment. This embodiment is merely an example, and it will be understood by those skilled in the art that various modifications are possible in terms of the combination of each component, and that such modifications are also within the scope of the present invention.

Reference Signs List 1 In-hole photography device 2 Rod 3 Drilling bit 4 Drilling rod 5 Hollow tube 10 Camera capsule 11 Lighting 12 Camera 13 Capsule body 14 Guide member 20 Guide mechanism 21 Guide member 22 Cover member 23 Pressurizing member 30a Recording capsule 30b Battery capsule 31 Recorder 32 Battery 33 Capsule body 34 Guide member 40 Cable 50 Damper member 51 Circumferential groove

Claims (5)

An in-hole photography device for photographing the inside of a hole drilled by a drilling rod having a drilling bit attached to the tip of the rod,
A capsule body that can be inserted into a hollow tube that communicates with the drilling rod from the hole mouth side to the tip and opens at the tip of the drilling bit;
A fixing mechanism for fixing the capsule body, which is transported toward the tip of the drilling rod by an air flow or a water flow, to the tip of the drilling rod;
The capsule body includes a camera for photographing the inside of the hole, a recorder for recording the image photographed by the camera, and a battery for supplying power to the camera and the recorder .
The capsule body includes a plurality of capsule bodies connected to each other,
The camera, the recorder, and the battery are distributed and built into the capsule bodies,
The borehole imaging device is characterized in that the plurality of capsule bodies are connected via a damper member . An in-hole photography device for photographing the inside of a hole drilled by a drilling rod having a drilling bit attached to the tip of the rod,
A capsule body that can be inserted into a hollow tube that communicates with the drilling rod from the hole mouth side to the tip and opens at the tip of the drilling bit;
A fixing mechanism for fixing the capsule body, which is transported toward the tip of the drilling rod by an air flow or a water flow, to the tip of the drilling rod;
The capsule body includes a camera for photographing the inside of the hole, a recorder for recording the image photographed by the camera, and a battery for supplying power to the camera and the recorder.
a guide mechanism for guiding transportation of the capsule body, the guide mechanism including a guide member that is attached to an inner circumferential surface of the hollow tube and a cover member that biases the attached guide member in a radial direction;
This borehole photography device is characterized in that the guide member fits into a circumferential groove formed on the inner surface of the tip of the borehole drilling rod, and the cover member is forced into contact with the inner surface of the hollow tube, so that the guide mechanism functions as the fixing mechanism. The capsule body includes a plurality of capsule bodies connected to each other,
3. The borehole photographing device according to claim 2 , wherein the camera, the recorder and the battery are distributed and built into a plurality of the capsule bodies. 4. The borehole imaging device according to claim 3 , wherein the capsule bodies are connected to each other via a damper member. The borehole imaging device according to any one of claims 1 to 4, characterized in that, when the capsule body is fixed to the tip of the drilling rod by the fixing mechanism, the fixing mechanism functions as a shielding mechanism that blocks the air flow or water flow that transports the capsule body.

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