JPH0575052B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> The present invention relates to a hole curvature measuring device, and particularly to a device for measuring the degree of curvature of an excavated hole.

《Conventional technology》 Normally, holes drilled with a poling machine etc.
It does not have perfect straightness and is curved in either direction, and horizontally parallel drilling holes in particular tend to tilt downward due to the gravity acting on the boring machine.

By the way, in relatively small-diameter excavated holes such as advanced pilot holes in oil fields, wells, and tunnels, for example, in advanced pilot holes, the curvature of the pilot hole must be measured in order to accurately determine the positional relationship with the main shaft.

For this reason, conventionally, a measurement tube is used, which is made by connecting two cylinders containing a laser oscillator and a television camera with a flexible member, and this is introduced into the borehole, and the measurement tube is connected to the front and back of the flexible member. A measuring device was used that used a laser beam and a television camera to detect the difference in inclination angle between the cylinders.

This type of measuring device takes measurements while sequentially moving inside the borehole, but the movement is done in an inchworm-like manner so that the optical axis from the previous measurement becomes the reference optical axis for the next measurement. Ta.

<<Problems to be Solved by the Invention>> In the conventional measuring device described above, the movement is performed in an inchworm-like manner, and therefore, the length of the excavation hole to be measured is divided by approximately 1/2 of the length of the measuring pipe, and the movement is performed many times.

Therefore, there was a problem in that errors from each measurement were accumulated, resulting in a decrease in measurement accuracy.

In order to reduce the measurement rotation, it is possible to lengthen the overall length of the measurement pipe, but the degree of bend in the drilling hole varies, and if it is made to be infinitely long, the inclination will be absorbed by the cylindrical body, making it difficult to accurately bend the hole. becomes unmeasurable.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a hole curvature measuring device that can reduce the number of measurements and improve measurement accuracy.

<Means for Solving the Problems> In order to achieve the above object, the present invention provides a rail that is attached to a flexible pipe inserted into an excavation hole and bends according to the bending of the pipe, and a measuring tube formed by rotatably connecting one ends of a pair of cylinders to be placed, and a light receiving displacement detecting device and a laser emitting device respectively built in the other end of the cylinders, A hole bending measuring device in which the measuring tube is supported at three points equally spaced on the rail,
A traveling device is disposed at each of the support points, and the distance between the support points is variable.

《Operation》 Since the distance between the support points of the measurement tube is variable, for example, preliminary measurements are made at the shortest support point distance.
After understanding the outline of the curvature of the excavation hole and optimally setting the distance between supporting points, the actual measurement is performed, which reduces the number of measurements and allows the curvature to be measured with high precision.

<<Example>> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show an embodiment of a hole bending measuring device according to the present invention.

The hole bending measuring device shown in FIG. 1 is a pair of hollow cylindrical bodies 10, 1
A measurement tube 14 rotatably connected to one end of 0a by a ball joint 12 having a through hole formed therein.
and a CCD target 16 provided near the tip of one of the cylinders 10 so as to be orthogonal to the cylinder axis.
The other cylindrical body 10a has a laser beam emitting device 18 provided on the cylinder axis near the rear end, and the target 16 has a planar shape in which CCD elements are arranged in a two-dimensional direction. When placed horizontally,
The laser beam projected from the emitting device 18 is adjusted so as to irradiate the origin.

Below the cylinders 10, 10a are three sets of rotating rollers 20a, 20b, 2 driven by an electric motor or the like.
0c is provided, and rollers 20a, 20 on both sides
b, 20c are attached to arms 22, 22 housed inside the cylindrical bodies 10, 10a, respectively, and are extendable and retractable between the solid line and the imaginary line in FIG.

The measurement pipe 14 is an excavated hole 24 dug almost horizontally.
However, the pipe 2 is inserted into the excavation hole 24 in advance.
6 is inserted.

The pipe 26 has the possibility of deforming along the curve of the excavation hole 24, and is suitably made of, for example, a vinyl chloride pipe or a relatively thin aluminum pipe.

Furthermore, a concave rail 28 is installed inside the pipe 26 and extends along the axial direction of the pipe 26.
The four rollers 20a, 20b, 20c are placed on this rail 28, and the rollers 20a, 20
This is supported at three points where b, 20c and the rail 28 contact.

The principle of the measuring device is that a bend in the excavation hole 24 appears in the pipe 26 and rail 28, and the relationship between the laser beam of the emitting device 18 and the target 16, whose origin has been adjusted in advance, deviates at the bend. The radius of curvature of the excavated hole 24 can be calculated by repeating measurements in an inchworm-like manner along the axial direction of the excavated hole 24 and obtaining each deviation amount.

In the measuring device of the present invention, first, as shown by solid lines in FIG.
The arms 22 of b and 20c are shortened and the measurement tube 14 is supported at the shortest support points (A ₁ , A ₂ , A ₃ ) at equal intervals L ₁ to perform a preliminary measurement.

When the approximate curve and radius of curvature of the excavated hole 24 are determined as a result of preliminary measurements, the deviation in the axial direction of the hole 24 is examined, and the longest distance between supporting points L ₁ +L ₂ is determined according to the deviation.

Once the distance L ₁ + L ₂ between the support points is determined, the arm 22 is extended correspondingly, and the support points on both sides are A ₁
→A ₁ ′, A ₃ →A ₃ ′ and measure again.

In the main measurement, the distance between the supporting points was larger than in the preliminary measurement, so the same drilling hole 24
The number of measurements is significantly reduced, the cumulative error is reduced, and the measurement accuracy is therefore improved.

Although the measuring tube 14 can be moved by pushing the entire tube in from behind, it is preferable to drive the rotary rollers 20a, b, and c by, for example, a stepping motor to move the measuring tube 14 by a fixed length.

<<Effects of the Invention>> As described above in detail in the embodiments, according to the hole bending measuring device according to the present invention, the supporting point of the measuring tube can be set to the longest length according to the degree of bending of the hole, so that the measurement The number of times of measurement can be reduced, and measurement accuracy can be significantly improved.

[Brief explanation of the drawing]

FIG. 1 is an overall explanatory view showing one embodiment of the apparatus of the present invention, and FIG. 2 is a sectional view of FIG. 1. 10, 10a...Cylinder, 12...Ball joint, 14...Measuring tube, 16...Target, 1
8... Laser emitting device, 20a, b, c... Rotating roller.

Claims (1)

[Claims] 1. A rail that is attached to a flexible pipe inserted into an excavation hole and bends according to the bending of the pipe;
and a measurement tube formed by rotatably connecting one ends of a pair of cylinders placed on the rail, and a light receiving displacement detecting device and a laser emitting device are respectively provided at the other end of the cylinders. A hole bending measuring device that has a built-in measuring tube and supports the measuring tube at three points equally spaced on the rail, and a traveling device is provided at each of the supporting points, and the distance between the supporting points is variable. A hole bending measuring device characterized by: