JPS62132111A - Apparatus for measureing horizontal displacement of underground excavator - Google Patents

Abstract

PURPOSE:To continuously obtain the accurate data of the horizontal displacement mode of an underground excavator from an execution scheme line in a real time, by laying one or more magnetic field generating cables to the surface of the earth and an appropriate magnetic field detection element is arranged in the side of the underground excavator to detect the magnetic field generated from each of said cables. CONSTITUTION:A current is supplied to the magnetic field generating cable 10 laid on the surface of the earth EP from an operation panel 30 while magnetic field detection elements S1, S2 are arranged to an underground excavator 20. The element S1 is fixed so that a magnetic field detecting direction is inclined by a predetermined angle from a vertical direction when looked from the front surface of the excavator 20 in the advance direction thereof and the element S2 is fixed so that a magnetic field detecting direction crosses the magnetic field detecting direction of the element S1 at an angle coming to line symmetry with respect to a vertical direction axis when looked from the front surface of the excavator 20 in the advance direction and both elements detect the magnetic field generated from the cable 10. The operation panel 30 compares the detected magnetic field levels by the elements S1, S2 to judge the horizontal displacement of the excavator 20 in the left and right direction with respect to the cable 10.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is aimed at promoting the construction schedule of an underground excavator that excavates tunnels to bury water pipes, gas pipes, etc. underground. The present invention relates to a measurement device for an underground excavator that measures the horizontal displacement of an underground excavator underground.

[Conventional technology]

Conventionally, relatively small-diameter underground excavators for the purpose of burying water pipes and gas pipes have been
Due to the small size of the excavation site and the frequent curved excavation, optical surveying using radar transit etc. cannot be applied to measure and confirm the excavation position.
In particular, the reality is that it is impossible to accurately measure displacement in the horizontal direction. In response to this problem, recently a magnetic generation element has been installed inside the underground excavator, and the characteristics of the alternating magnetic field generated from this magnetic generation element on the earth's surface are used to generate a magnetic field directly above the underground excavator. The method of measuring the displacement from the above ground point was
1030 Title of invention: “Horizontal position detection method for shield aircraft”
Several proposals have been made based on this.

[Problem that the invention seeks to solve]

Although this method can certainly measure the horizontal position of an underground excavator, in practical use it is difficult to measure the horizontal position of an underground excavator, but in practical use, the probe with the magnetic detection The need to transport, install, and explore new problems will arise, such as an increase in the number of people in charge of measurements and the need for more labor and time for measurements. Furthermore, such a measurement method is almost impossible on roads with a lot of traffic, and frequent traffic closures would negate the original advantage of the management method using underground excavators.

[Means and effects for solving the problem] In the present invention, one or more magnetic field generating cables are laid on the ground surface in accordance with the construction plan line of the underground excavator, and An appropriate magnetic field detection element is disposed on the side of the machine to detect the magnetic field generated by the cable. The characteristics of this magnetic field are different between the positive half direction and the left half direction with the vertical plane of the same cable as a boundary, and the difference in the characteristics of the magnetic field is determined based on the output of the magnetic field detection element described above. By doing so, it is possible to effectively and continuously identify and measure in real time whether the underground excavator is to the right or to the left with respect to the vertical plane of the cable.

Incidentally, when correcting the horizontal displacement of such an underground excavator, it is possible to sufficiently control the horizontal displacement with only binary information such as rightward displacement or leftward displacement obtained by the measurement.

〔Effect of the invention〕

As described above, according to the present invention, accurate data regarding the horizontal displacement mode of an underground excavator from the construction planning line can be obtained by simply laying the magnetic field generating cable on the ground surface in advance according to the construction planning line. can be obtained continuously in real time. Therefore, as long as the above-mentioned cables are protected against passing vehicles, etc., there is no need to block traffic at all, and the underground excavator in question can be continuously controlled in accordance with the continuous collection of the above-mentioned data in real time. This will greatly improve construction accuracy.

〔Example〕

First, the present invention will be explained in detail with reference to FIGS. 4 to 6.

Now, as shown in Fig. 4, if a magnetic field generating cable 10 is laid on the earth's surface EP and an appropriate current is passed through it, the cable 1o is centered and its surroundings are as shown in Fig. 4. A magnetic field H is generated concentrically in this manner. In this invention, the magnetic field H thus generated is simultaneously detected by two magnetic field detection elements S1 and S2 as shown in the figure.

For the sake of simplicity, these two magnetic field detection elements S1 and S2 have their magnetic field detection directions perpendicular to each other, and each has an angle of
Assume that the angle is maintained at 5 degrees.

Under these conditions, the two magnetic field detection elements 81
The level ratio of the magnetic field detected by S2 is determined by the angle θ formed by the vertical plane VP seen from the magnetic field generating cable 10 and these magnetic field detecting elements S1 and S2. It now takes the value of the species.

That is, as shown in FIG. 5, when expressed by the level ratio iR of these detected magnetic fields, the level ratio Ri is R:=cot in the region A where θ≦−45°, respectively.
(θ-45°) ■ R=-e in region B where -45°≦θ≦09
at(θ-45°) ■ In region C where 06≦θ≦45°, R=-j
an(θ-45°) ■ In the region where 450≦θ, R=jan(θ
-450). In this FIG. 5, D indicates the underground depth of the magnetic field detection elements S1 and S2, and the value of the level ratio R is numerically calculated for each value of the underground depth D, and this is graphed. Figure 6 shows the result.

In the graph of FIG. 6, three types of underground depths such as D=1 m, 2 m, and 3 m are assumed, and the level ratio R of the magnetic field detected by the magnetic field detecting elements S1 and S2 is assumed for each of these underground depths.
This represents the relationship between the amount of horizontal displacement of the magnetic field detection elements S1 and S2 from the vertical plane vp of the cable 10.

Now, according to the graph of FIG. 6, the two magnetic field detection elements S1 and S2 placed under the above-mentioned nine conditions are displaced with respect to the cable 10 in the vertical plane ■P, that is, the horizontal displacement amount is "0".
'', it can be seen that the level ratio of each detected magnetic field is ``1'' no matter what the underground depth D is. Moreover, when these magnetic field detection elements S1 and S2 are displaced in the right half direction from the position of the horizontal displacement amount "0", the same level ratio R becomes R(1; conversely, when they are displaced in the left half direction, Same level ratio R
becomes R)1, and this exception does not occur.

To summarize the above, two magnetic field detection elements S1 and S2 whose magnetic field detection directions are orthogonal to each other and each maintained at an angle of 45 degrees with respect to the vertical plane vP of the magnetic field generating cable 1o can be used to When detecting the generated magnetic field, if the level ratio R of these detected magnetic fields is R = 1, these magnetic field detection elements S1 and S2 are at the position of horizontal displacement "0" with respect to the same cable 10, and the same level ratio R is R<1
If so, the same magnetic field detection elements S1 and S2 are connected to the same cable 1.
If the same level ratio R is R)l at a position displaced in the right half direction with respect to 0, the same magnetic field detecting elements Sl and S
2 is at a position displaced in the left half direction with respect to the same cable 10.

Note that here, the above two magnetic field detection elements 81 and S2
Although the arrangement angle with respect to the cable vertical plane vP is limited as described above, basically, the magnetic field detection directions of these magnetic field detection elements S1 and S2 are maintained at an angle that is symmetrical with respect to the cable vertical plane vP. All you have to do is
Judgments regarding the horizontal displacement mode are made based on the same principle as above in Figures 1 to ! FIG. 3 shows an embodiment of the horizontal displacement measuring device for an underground excavator according to the present invention constructed based on such a principle. The configuration and operation of the example will be explained in detail.

FIG. 1 schematically shows, with a cross-sectional view, the rough configuration of the apparatus of this embodiment including an underground excavator in a working state. In addition, FIG. 2 schematically shows the cross-sectional structure of the main part of the apparatus of this embodiment as seen from the direction of movement of the underground excavator. In these figures, EP is the ground surface, 10 is a magnetic field generating cable laid over the construction plan line (not shown) on the ground surface EP, 20 is an underground excavator, 21 is a part of the excavator 20, and 22 is the spatula P21. 23 is a propulsion arm that propels the support arm 22; S1 and S2 are the aforementioned magnetic field detection elements made of coils, and 24 is the magnetic field detection direction of these magnetic field detection elements S1 and S2 that is always first. 4) Support arm 22 of the 11J machine 20
A posture support frame 25 supports the magnetic field detection element S1
A signal line 30 for transmitting the detection signals of the magnetic field detecting elements S1 and S2 is provided on the ground as shown in the figure, and supplies power to the cable IO, and also transmits the detection signals of the magnetic field detecting elements S1 and S2 via the signal line 25. Based on the drawings, operation panels for collectively executing signal processing for horizontal displacement measurement of the underground excavator 20 in question are shown. The configuration of this operation panel 30 is shown in detail in FIG.

That is, as shown in FIG.
1. A power amplifier 32 that amplifies the power of the oscillated AC signal and supplies it to the magnetic field generation cable 10, and magnetic field detection elements Sl and S that are transmitted via the signal line 25.
Signal amplifiers 33a and 33b that amplify the two magnetic field detection signals with the same gain, and a level comparator 3 that compares the signal levels of these two amplified magnetic field detection signals.
4, and a display driver 35 that controls the lighting IQ of a display 36 consisting of two lamps, one for indicating right displacement and one for indicating left displacement, based on the level comparison result. Based on the above principle, signal processing for measuring the horizontal displacement of the underground excavator 20 is executed in the following manner.

Now, if the magnetic field generating cable IOK AC current is supplied through the oscillator 31 and the power amplifier 32, a concentric magnetic field H centered on the cable 10 as shown in FIG. 4, for example, is generated. This occurrence depends on whether the magnetic field detection elements S1 and S2 mounted in the underground excavator 20 in the manner shown in FIG. The level ratio R of the magnetic field detected by these elements S1 and S2 with respect to the magnetic field detected by the elements S1 and S2 increases and decreases with "l" as the boundary, as stated in the previous explanation of the principle.

This operation panel 30 displays the relationship such as whether the level ratio R of the detected magnetic field by these 92 magnetic field detecting elements Sl and S2 is R (1 but R) 1, and the magnitude relationship of the level of each detected magnetic field. The magnitude relationship between the levels of these detected magnetic fields is directly determined through the level comparator 34.

As a result 1, for example, if the level of the magnetic field detected by the magnetic field detecting element 5IIC is higher than the level of the magnetic field detected by the magnetic field detecting element S2, the right displacement indication lamp of the display 36 is lit through the display driver 35, It is displayed that the underground excavator 20 in question is currently displaced to the right with respect to the construction plan line.

If the magnitude relationship between these levels is reversed, the left displacement indicating lamp on the display 36 is turned on. However, the lighting mode of these lamps may be reversed depending on the configuration of the device and the mode of wiring, so in practical use, the same lighting factor may be used to ensure proper displacement measurement according to the actual situation of the device. Adjustments will be made.

In this way, as the underground excavator 20 excavates, the horizontal displacement of the excavator 20 from the cable 10 (from the construction plan line) is continuously measured, and the content of this measurement is displayed through the display 36. Monitored sequentially in real time. Furthermore, it is easy to measure this amount of displacement based on FIG. 6 above.

In the above embodiment, an alternating current is supplied to the magnetic field generating cable 10, but the supplied current may of course be a direct current.

Also, the magnetic field generating cable 10 itself does not have to be a single wire, and may be a plurality of cables or a bundle of a plurality of cables. For example, the same effect as described above can be obtained by laying cables so as to reciprocate at constant intervals and aligning the centers of these cables with the construction plan line.

In addition, in the same example, the magnetic field detection directions (angles) of the two magnetic field detection elements were set according to the principle explained based on @Figures 4 to 6, but as supplemented in the explanation of the same principle. Basically, the magnetic field detection directions of these elements only need to be maintained at angles that are symmetrical to each other with respect to the vertical plane of the cable. That is, in such a case, the value of the level ratio (R) of the magnetic field detected by these magnetic field detecting elements for determining the above-mentioned left and right displacement mode may be changed according to the set angle.

Incidentally, the displacement of the underground excavator in the depth direction can be measured with sufficient accuracy by using a well-known inclinometer.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view schematically showing the configuration of an embodiment of the horizontal displacement measuring device for an underground excavator according to the present invention, and FIG. 2 is a partial cross-sectional view of the same embodiment as seen from the front direction. Figures 3 and 3 are schematic diagrams showing the configuration of the operation panel of the same embodiment device, Figures 4 and 5 are schematic diagrams for explaining the measurement principle of this invention, and Figure 6 is a schematic diagram showing the configuration of the operation panel of the same embodiment device. It is a graph which shows the relationship between the level ratio of the magnetic field detected by the two magnetic field detection elements shown in the figure, and the amount of horizontal displacement from the center of the magnetic field. 10... Magnetic field generation cable, 20-... Underground excavator,
21... To, C, 22... Support arm, 23-...
Propulsion jack, 24... Attitude support frame, 25... Signal line, 30... Operation panel, 31... Oscillator, 32...
Power amplifier, 33a, 33b... Signal amplifier, 34
... Level comparator, 35 ... Display driver, 36
...Indicator, Sl. S2...Magnetic field detection element.

Claims (3)

[Claims] (1) One or more magnetic field generating cables laid on the ground surface, a current supply means for supplying an appropriate current to the cables, and a current supply means disposed on an underground excavator such that the magnetic field detection direction is set in the direction of travel of the excavator. A first magnetic field detection element is fixedly supported to detect the magnetic field generated from the cable and is tilted at a predetermined angle from the vertical direction when viewed from the front; is fixedly supported in a direction that intersects the magnetic field detection direction of the first magnetic field detection element at an angle that is symmetrical about the vertical axis when viewed from the front in the traveling direction of the excavator, and the magnetic field generated from the cable is transmitted. a second magnetic field detecting element for detecting; and a determining means for determining horizontal displacement of the underground excavator to the right or left with respect to the cable based on a comparison of the magnetic field levels detected by the first and second magnetic field detecting elements. Horizontal displacement measurement device for underground excavators. (2) The predetermined angle of the first and second magnetic field detection elements with respect to the vertical direction when viewed from the front in the traveling direction of the excavator is 45
A horizontal displacement measuring device for an underground excavator according to claim (1). (3) The determination means determines the horizontal displacement of the underground excavator based on the magnitude relationship between the magnetic field levels detected by the first and second magnetic field detection elements.
Horizontal displacement measuring device for an underground excavator as described in ).