JP2000008771A - Cutting edge position detecting device of excavator and excavating direction control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely detect a cutting edge position in long distance and dissolve the possibility of work interruption caused by a device failure in a cutting edge position detecting device equipped at a propulsion excavator propelling a lead pipe provided with a drilling head (cutting edge) at the front end, from a start pit toward an arrival pit and collimating a target disposed at the drilling head, by a telescope of a theodolite on the start pit side to detect the position. SOLUTION: A reflection target 4 formed of a prism sheet is disposed at the base end of a drilling head 3. A laser projection system 10 is provided to project light into lead pipes 2, 2,... along the optical axis of a telescope 6 and to irradiate the reflection target 4. An image of the telescope 6 is taken into a CCD camera and transferred to a personal computer 12 to detect the center position and cutting edge position of the drilling head 3 by image processing. On the basis of the detected positions of the drilling head 3, a control device 31 controls the operation of a propulsion excavator to automatically correct the excavating direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting blade position detecting device for detecting the position of a cutting blade at the front end of a propulsion pipe that advances in the soil, for example, in a propulsion excavator used for burying water pipes, and the like. The present invention relates to a digging direction management device that corrects a digging direction of a propulsion pipe to a target direction by using the device.

[0002]

2. Description of the Related Art Conventionally, a so-called small-diameter pipe propulsion method has been generally used for burying relatively small-diameter pipes such as water pipes and gas pipes. In this method, first, two vertical shafts, a starting shaft and a reaching shaft, are dug in the ground where the pipes are to be buried, and then the pipes are buried while excavating the soil from inside the starting shaft toward the reaching shaft. However, there is an advantage that it is hard to hinder traffic even in a situation where digging work is difficult such as in an urban area with heavy traffic. In this method, various methods such as press-fitting method, auger method, and boring method have been established according to the soil properties of the ground and the type of buried pipes. it can.

[0003] More specifically, referring to FIG. 2, a temporary pipe combined type two-step method called a speeder method will be described. In this method, first, a hydraulic propulsion excavator 1 is installed in a starting pit H1. The lead pipe (propulsion pipe) 2 attached to the propulsion excavator 1 is pushed forward while being rotated by a hydraulic mechanism, and is advanced toward the reaching pit H2 while consolidating the soil by the excavation head 3 at the front end of the lead pipe 2. , One after the other at the rear end of the lead tube 2,
Are added and penetrated to the reaching shaft H2 (see FIG. 7A).

Next, a buried pipe 35, a leading cutter 36 and a screw conveyor 37 are provided at the rear end of the last lead pipe 2.
Are rotated in the same manner as the lead pipes 22, 22,. That is, the buried pipe 3
, And screw conveyors 37, 37,... Are sequentially added, while the lead pipes 2, 2,.
While collecting the buried pipes 35, 3 toward the arrival pit H2.
Advance 5, ... At this time, the soil excavated by the leading cutter 36 is removed by screw conveyors 37, 37,
Are discharged through the subsequent buried pipes 35, 35,... (See FIG. 3B). And the top buried pipe 35
Reaches the reaching shaft H2, the leading cutter 36 is collected on the reaching shaft H2 side, and the buried pipes 35, 3 are recovered on the starting shaft H1 side.
The screw conveyors 37, 37,... Are pulled out and sequentially collected, and then the inside of the buried pipes 35, 35,.

As described above, in the speeder method, the lead pipes 2, 2,...
Although it is extremely important to reach 2, the excavating head 3 that advances in the soil receives an unbalanced force from the upper, lower, left, and right grounds, so that if it is released, it will gradually deviate from the target direction. Therefore, usually, a position detecting device for detecting the position of the excavating head 3 is used to constantly monitor and correct the excavating head so as not to leave the target direction.

[0006] Generally, as the position detecting device, a target provided on a drilling head and a theodolite for collimating the target are used.
That is, as shown in FIG. 9, for example, nine LEDs (light emitting diodes) 39, 39,... LED 39 emits yellow light, and
The LED 39 corresponding to the cutting edge position of the excavating head 3 (upper position in the figure) emits red light, and further, other LEDs
39, 39,... Emit green light.

On the other hand, the theodolite (see FIG. 2) is installed in the starting pit H1, and the LEDs 39, 3 are viewed from the rear end of the rearmost lead tube 2 along the axis of the tube.
The target consisting of 9,... Can be collimated. That is, the operator can easily recognize the center position of the excavation head and the position of the cutting edge thereof based on the difference in the emission color of the LED depending on the position of the target.

[0008]

By the way, in recent years, the maximum propulsion distance of the pipe has been extended due to the improvement of the performance of the excavator, and the interval from the starting pit H1 to the reaching pit H2 has been able to be set much longer than before. is there. By doing so, the number of shafts to be dug on the ground can be significantly reduced, so that a remarkably excellent effect can be obtained for shortening the construction period and cost, and furthermore, the construction will not hinder the traffic further. There is expected.

However, in the conventional cutting blade position detecting device, when the distance between the starting pit H1 and the reaching pit H2 becomes longer and the distance of the target from the theodolite becomes longer, the target image in the telescope field of view becomes smaller accordingly. As a result, it is inevitable that the visibility is rapidly reduced.
Therefore, the operator cannot recognize the center position and the cutting edge position of the excavation head, and it becomes difficult to correct the excavation direction accurately.

On the other hand, it is conceivable to enlarge the image of the target by increasing the magnification of the telescope, but in such a case, the entire image is often blurred and difficult to see, and the brightness of the image is increased. , The visibility is not much improved. In addition, even if the brightness of the image is increased by increasing the light emission amount of the LED, only the entire field of view of the telescope becomes bright, and the contrast of the image is not significantly improved.

Further, in the above-mentioned conventional cutting edge position detecting device, an LED is provided on the excavating head so as to emit light, so that the vibration or heat generation of the excavating head causes a defective conduction of an electric circuit or a failure of the LED. There is a fear. In such a case, it is extremely difficult to recover and repair the excavating head that has penetrated deep into the soil, so that it is practically impossible to proceed with the construction normally.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned points, and an object of the present invention is to elaborate the configuration of a cutting edge position detecting device so as to detect a long-distance cutting edge which could not be detected until now. An object of the present invention is to make it possible to reliably detect a position and to eliminate a possibility of work being interrupted due to a failure of a device.

[0013]

In order to achieve the above object, according to the present invention, as a target indicating a cutting edge position, a retroreflecting means for reflecting incident light in the backward direction is used. Then, light was projected from the rear end side of the propulsion tube along the optical axis of the telescope to irradiate the target.

Specifically, the invention according to claim 1 includes a propulsion pipe provided with a cutting blade for excavating in the soil at a front end thereof,
A cutting blade position detecting device for detecting the position of the cutting blade in an excavator in which the propulsion pipe is arranged so that a cutting edge at a front end extends in a target direction and excavates while pushing the propulsion pipe from a rear end side to a front side. It is assumed. And a target provided at the rear end of the cutting blade so as to correspond at least to the axial center position of the propulsion pipe; and a target installed near the rear end of the propulsion pipe, collimating the target and setting the target direction. And a theodolite for measuring the position of the cutting blade with respect to the target, the target is constituted by retroreflecting means for reflecting incident light in the backward direction, and near the rear end of the propulsion tube. And a projection optical system for projecting light into the tube along the optical axis of the telescope of the theodolite and irradiating the target.

Here, the backward direction refers to the direction in which the reflected light beam is superimposed on itself, in other words, the direction in which the reflected light beam travels in the reverse direction along the same path that passed before inversion. For example, a corner cube prism or the like may be used as the retroreflecting means for inverting the light beam.

According to the above arrangement, the light from the projection optical system enters the retroreflecting means as a target along the optical axis of the telescope, is reflected in the backward direction by the retroreflecting means, and is reflected by the telescope. Come back along the optical axis of. That is, almost all the reflected light from the retroreflecting means enters the objective lens of the telescope, so that the image of the target (retroreflecting means) in the telescope field of view has extremely high contrast. This makes it possible to reliably detect a long-distance cutting edge position that could not be detected conventionally.

Further, the retroreflection means does not require a power supply or an electric circuit unlike an LED, and does not fail itself. Therefore, a failure of an electric circuit or the like in the case of using an LED as in the prior art. Can be avoided reliably, and this can eliminate the possibility that the failure of the position detecting device may cause the progress of the construction to be stopped.

According to a second aspect of the present invention, the target according to the first aspect of the present invention is provided by a retroreflecting means provided to correspond to the axial center position of the propulsion tube and the cutting edge position of the cutting blade and to be distinguishable from each other. Constitute. Thus, the operator can recognize not only the center position of the cutting blade but also the direction of the cutting edge, so that when the digging direction is corrected, the direction of the cutting blade can be changed to an optimal direction for the correction.

According to a third aspect of the present invention, the target according to the first aspect of the present invention is a prism sheet having a predetermined shape capable of recognizing the position of the axis of the propulsion tube and the position of the cutting edge of the cutting blade. This prism sheet is formed by forming a large number of prisms in a plastic sheet by a fine processing technique. The prism sheet is formed into, for example, a triangular shape to serve as a target. What is necessary is just to attach so that a position may be recognized.

If the prism sheet is used,
An inexpensive and simple target can be obtained. Further, since substantially uniform reflected light is obtained from the entire surface of the prism sheet, recognition of the shape of the target is further facilitated.

According to a fourth aspect of the present invention, the projection optical system according to any one of the first to third aspects uses a laser beam as a light source. As a result, even if the target is at a long distance, the energy density of the light applied to the retroreflecting means can be increased, so that the contrast of the target image in the telescope field of view can be further increased, and thus the cutting edge can be increased. The detectable distance of the position detecting device can be further extended.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, an imaging means for inputting a target image obtained by a telescope of the theodolite is provided. As a result, the target image is input to the imaging means, so that data of the image can be transferred to a separate display device and displayed on the display screen. By doing so, the operator can observe the target in a more comfortable posture, and the workability is improved. Further, when correcting the excavation direction, the work can be performed while checking the display screen, so that the work time can be reduced and the reliability can be improved.

According to a sixth aspect of the present invention, a magnifying optical system for enlarging a target image is provided between the telescope and the imaging means in the fifth aspect of the present invention. As a result, the target image is enlarged, so that the position of the cutting edge and the direction of the cutting edge can be easily recognized, and accordingly, the correction of the excavation direction can be further facilitated. Further, since a commercially available telescope of the theodolite can be used as it is, it is advantageous in terms of cost.

Further, since the image enlarged by the optical system is inputted to the image pickup means, the performance of the image pickup means can be maximized. It should be noted that although the image becomes darker when enlarged, the contrast is sufficiently high so that there is no problem in visibility.

According to the seventh aspect of the invention, the fifth or sixth aspect is provided.
In the invention described in (1), a detection means for detecting at least the axial center position of the propulsion pipe based on data of the target image input to the imaging means is provided.

Thus, based on the data of the target image input to the imaging means, the detecting means detects the cutting edge position in accordance with an image processing technique such as pattern recognition. In particular, when a prism sheet is used as in the third aspect of the present invention, an image with substantially uniform brightness can be obtained over the entire surface of the prism sheet, so that the accuracy of image recognition is extremely high. If the position detection result by the detection means is displayed on, for example, a display screen, the operator can correct the excavation direction based on the display. Inadvertent mistakes in the detection of can be reliably eliminated.

Further, based on the detection result by the detection means, an alarm can be issued when the cutting edge position deviates from the target direction by a predetermined amount or more, so that the operator can set the cutting edge position. It is not necessary to continuously monitor for a long time, and workability is remarkably improved.

[0028] According to an eighth aspect of the present invention, in the seventh aspect of the present invention, a storage means for storing a detection result by the detection means in a time series is provided.

That is, for example, when the cutting blade collides with rocks in the soil and largely deviates from the target direction, the target image may move out of the field of view of the telescope, making observation impossible. Therefore, in the present invention, the position detection result by the detection means is stored in chronological order by the storage means. Therefore, even if the target image cannot be observed, the position detection result based on the previous detection result, that is, the trajectory of the target image is used. Thus, the current position of the cutting edge can be estimated. With this,
Even if the target becomes unobservable, the direction of the propulsion pipe can be corrected.

According to the ninth aspect of the present invention, the diameter of the propulsion pipe according to any one of the first to eighth aspects is 80.
cm or less. This embodies the size of the propulsion tube. That is, when the diameter of the propulsion pipe is 80 cm or less, it is not easy for the operator to go through the propulsion pipe to the front end thereof. It is extremely effective to be able to accurately detect the position of the cutting edge at the front end and to eliminate the occurrence of failure of the target provided on the cutting edge while staying there.

According to the tenth aspect of the present invention, a propulsion pipe provided with a cutting edge for excavating in the soil is provided at the front end, and the propulsion pipe is arranged so that the cutting edge at the front end extends toward the target direction. In addition, it is assumed that an excavating direction management device in an excavator that excavates while pushing forward from a rear end side to a front side. A target is provided at the rear end of the cutting blade so as to correspond at least to the axial position of the propulsion tube, and includes a target formed of retroreflecting means for reflecting incident light in the reverse direction, and a target after the propulsion tube. A theodolite installed near the end, collimating the target and measuring the position of the cutting blade with respect to the target direction, and provided near the rear end of the propulsion tube, to the optical axis of the telescope of the theodolite A projection optical system that irradiates the target by projecting the light along a tube, imaging means for inputting a target image obtained by the telescope of the theodolite, and data of the target image input to the imaging means. A detecting means for detecting at least the axial center position of the propulsion pipe, and a control means for controlling the operation of the excavator based on the detection result by the detecting means so that the traveling direction of the propulsion pipe becomes the target direction. To be

With this configuration, the same operation as the first and seventh aspects of the invention can be obtained, and even if the target is at a long distance, the position of the cutting edge can be reliably detected by the detecting means, and the detection result can be obtained. By controlling the operation of the excavator based on the above, the excavation direction can be automatically corrected.

[0033]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of a cutting edge position detecting device A of an excavator according to an embodiment of the present invention. The cutting edge position detecting device A is used for cutting a buried pipe such as a fume pipe by a speeder method, for example. It is mounted on the propulsion excavator 1 to be buried inside. The propulsion excavator 1 is installed in the starting pit H1 as shown in FIG. 2 and operates by operating hydraulic pressure supplied from a hydraulic pressure supply unit (not shown) installed outside the starting pit H1.

In FIG. 1, reference numerals 2, 2,... Denote lead pipes that first penetrate from the start pit H1 to the destination pit H2 in order to lead the buried pipe. These lead tubes 2, 2, ...
It consists of a stainless steel pipe with a diameter of about 10 cm, and a cutting head (cutting edge) 3 is attached to the front end of the lead pipe 2 at the head, while the rear end of the lead pipe 2 at the tail is in the starting pit H1. It is connected to a hydraulic drive unit (propulsion mechanism) of the installed propulsion excavator 1. And the lead tube 2,2, ...
Are driven forward along this axis while being rotated clockwise about the central axis of the tube. Also, the tip end surface of the excavating head 3 is inclined with respect to the axis of the lead tube 2, while the rear end surface of the excavating head 3 is perpendicular to the axis of the lead tube and faces the inside of the tube. Is provided with a reflection target 4 formed of a prism sheet.

On the other hand, a theodolite (theodolite) 5 is installed in the vicinity of the rear end of the last lead tube 2, and the telescope 6 looks inside the lead tubes 2, 2,. It can be collimated. The theodolite 5 is supported on a gantry 7 at three locations via height adjusting screws, and is supported on the horizontal board 8 so as to be pivotable about a vertical axis. It has a U-shaped support portion 9 that is rotatably supported around an axis, and can collimate the reflection target 4 in the telescopic field of view to measure the horizontal angle and the vertical angle thereof with high accuracy.

The telescope 6 has a laser projection system (projection optical system) for projecting a laser beam forward along the optical axis x.
A laser beam (indicated by an arrow in the figure) emitted from the laser projecting system 10 is reflected by the reflection target 4 and returns along the optical axis x of the telescope 6 to be telescoped. It appears as an image of the reflection target 4 in the field of view. Further, the telescope 6 receives the image of the reflection target 4 and transmits the data of the image to the personal computer 1 installed outside the starting pit H1 by the communication cable 11.
2, an image pickup system 13 for transferring the image data is provided.

As shown in FIG. 3, the reflection target 4 is a prism sheet formed in the shape of an isosceles triangle that is long vertically and attached to the rear end surface of the excavating head 3. In addition, the designated vertex (upper vertex in the figure) 4b facing the bottom is associated with the cutting edge position of the excavating head 3, and goes from the center position 4a to the designated vertex 4b. The pointing direction can be easily identified. As is well known, the prism sheet is formed by forming a large number of prisms in a plastic sheet by a fine processing technique, and, like a corner cube prism or the like, reflects almost all incident light in the backward direction. .

The optical system of the telescope 6 and the laser projection system 10 is configured as shown in FIG. That is, the laser beam output from the semiconductor laser device (laser transmitter) 15 as a light source is first adjusted in divergence angle by a pair of condenser lenses 16, 16, and then deflected by 90 ° by the right-angle prism 17. , Focusing lens 18
, The light is again deflected by 90 degrees by the right-angle prism 19 arranged on the optical axis x of the telescope 6, and the objective lens 2
The light is projected toward the reflection target 4 along the optical axis x of the telescope 6 through the optical axis 0. It is preferable that the diameter of the light beam of the laser beam is set to be slightly larger than the diameter at the front end of the lead tube 2.

The laser beam reflected by the reflection target 4 and returned along the optical axis x of the telescope 6 is condensed by the objective lens 22 of the telescope 6 to form an image of the reflection target 4. . That is, the image of the reflection target 4 is turned upside down and left and right by the roof prism 23, passes through a focusing mirror 24 having a built-in crosshair, is enlarged by an enlargement optical system 25, and is input to a CCD camera (imaging means) 26. You.

The CCD camera 26 moves back and forth and is fixed at an arbitrary position. When the CCD camera 26 is moved forward, the image of the reflection target 4 is changed as shown in FIG. By making the CCD camera 26 recede, the image of the reflection target 4 can be enlarged as shown in FIG. 5B. In addition, the focusing lens 27 is moved along the optical axis in response to the forward or backward movement of the CCD camera 26.
The image of the reflection target 4 is always formed on the imaging surface of the CCD camera 26. In FIG. 4, reference numeral 28 denotes a focusing lens of the telescope 6, and reference numerals 29 and 29 denote CCs from the telescope 6 respectively.
The right-angle prism deflects the laser beam reaching the D camera 26.

The CCD camera 26 transfers the input image data to the personal computer 12 as an NTSC signal. This personal computer 12
Has a dedicated image processing board built-in, and transfers the transferred data at a predetermined cycle (for example, every several hundred milliseconds).
By performing the processing, the center position 4a of the reflection target 4 and the pointing direction thereof are detected. Specifically, FIG.
As shown in the flow shown in (1), in step S1, a signal input from the CCD camera 26 is accepted to acquire image data, and in subsequent step S2, background noise is removed by filtering.

Subsequently, in step S3, the coordinates of three vertices of the isosceles triangle of the image are obtained, and the pattern of the reflection target 4 is recognized based on the coordinates of the vertices. In step S4, the center position 4a of the reflection target 4 is calculated based on the coordinates of the three vertices. In step S5, the length of the base of the isosceles triangle of the image (indicated by an arrow in the figure) is set as the target size. Ask for. Subsequently, in step S6, the distance to the reflection target 4 is calculated based on the target size, and
The shift amount of the center position coordinate calculated in step 4 from the coordinate origin, that is, the shift amount of the target center from the target direction is calculated, and the direction of the designated vertex 4b with respect to the center position 4a is obtained.

Then, in step S7, as shown in FIG. 7, for example, the image of the reflection target 4 after noise removal and the calculation result of the shift amount are output to the monitor display 30 of the personal computer 12 and displayed to the operator. I do.

The processing in each step of the flow of FIG. 6 is realized by executing a program electronically stored in the memory of the personal computer 12 or the ROM of the image processing board by the microprocessor (CPU). . That is, detection means is constituted by the CPU and the image processing board.

Although not shown, the personal computer 12 has a built-in storage device (storage means) such as a hard disk. The storage device stores the displacement of the target center 4a and the direction of the designated vertex 4b detected as described above. The detection results are stored in chronological order.

Next, a method for managing the direction of excavation using the cutting edge position detecting device A will be described.

First, the operator attaches the first lead pipe 2 to the propulsion excavator 1 and checks the image of the reflection target 4 on the monitor display 30 while checking the center position of the image with the center position of the crosshair (coordinate origin). ), That is, the direction of the lead tube 2 is determined so that the center position of the lead tube in the excavation head 3 matches the target direction. Next, the propulsion excavator 1 is operated, and the lead pipe 2
When the lead pipe 2 advances to the full propulsion stroke of the hydraulic mechanism of the propulsion excavator 1,
Then connect the next lead tube 2 to the end and push them again. Then, the above operations are repeatedly executed.

At this time, the image of the reflection target 4 on the screen of the monitor display 30 is ideally gradually rotated clockwise around the center position while the center position coincides with the coordinate origin. However, in practice, the excavating head 3 advancing in the soil is gradually departed from the target direction due to the reaction force from the ground, so that the center position of the image also gradually deviates from the coordinate origin. To go.

Therefore, the operator monitors the image of the reflection target 4 on the display screen, and when the image deviates from the coordinate origin by a predetermined amount or more, for example, as shown in FIG. 7, the operation of the propulsion excavator 1 is temporarily stopped. . While confirming the image on the display screen, the propulsion excavator 1 uses the propulsion excavator 1 until the indicated direction of the image indicates the coordinate origin, that is, until the cutting edge of the excavation head 3 is directed to the target direction.
2. Rotate in place.

Subsequently, the propulsion excavator 1 pushes the lead pipes 2, 2,... Forward without rotating them. In this case, since the excavation head 3 has its tip blade tip surface inclined with respect to the axis of the lead pipe 2, the excavation head 3 advances toward the cutting edge side as a whole.
The excavation direction of the lead pipes 2, 2, ... is corrected so as to approach the target direction.

Further, for example, when the excavating head 3 collides with rocks in the soil and largely deviates from the target direction, the target image moves out of the telescope field of view and becomes unobservable. Reproduces the time-series position detection result stored in the storage device of the personal computer 12, that is, the trajectory of the target image on the monitor display 30, and based on the trajectory, the current position of the unobservable excavation head 3 Is estimated. Then, the excavation direction of the lead pipe 2 can be corrected based on the estimated position of the excavation head 3.

Therefore, according to the cutting edge position detecting device A of this embodiment, the laser beam is projected from the laser projecting system 10 on the starting pit H1 side to the reflection target 4 disposed on the rear end face of the excavating head 3. Thus, even if the reflection target 4 is at a long distance, it is possible to irradiate light having a sufficiently high energy density.
Further, since the reflection target 4 is constituted by a prism sheet, almost all of the laser beam reflected from the reflection target 4 can be incident on the objective lens 22 of the telescope 6. As a result, the image of the reflection target 4 in the telescope field of view becomes extremely high in contrast, and the drilling head 3
Is at a long distance that cannot be detected by conventional devices,
The position can be reliably detected. Therefore, in the propulsion work, the excavation direction can be controlled even if the distance between the start pit H1 and the arrival pit H2 is significantly increased, so that remarkably excellent effects such as shortening of the work period and cost reduction can be obtained.

In addition, since the reflection target 4 can be formed inexpensively and simply by using a prism sheet, and substantially uniform reflected light can be obtained from the entire surface of the reflection target 4, the target image can be more easily recognized. Become. This provides an effective effect particularly when performing image processing. In addition, since the reflection target 4 is illuminated from the starting pit side, and a power source or an electric circuit is not required on the excavation head side, L which has been a concern in the conventional apparatus is not considered.
Failure of the ED, electric circuit, and the like can be reliably avoided.

Further, since the image of the reflection target 4 is enlarged by the magnifying optical system 25 and taken into the CCD camera 26, the performance of the CCD camera 26 can be maximized. In addition, since the image is enlarged, the visibility is improved even on the screen of the monitor display 30, and the position detection accuracy by the image processing is improved.
Although the image of the reflection target 4 becomes darker when enlarged, the contrast is extremely high as described above, so that there is no problem in visibility.

Further, in this embodiment, image processing such as pattern recognition is performed based on the image data captured by the CCD camera 26, and the axial positions of the lead tubes 2, 2,. Is detected and the detection result is displayed on the display screen, so that the operator can correct the excavation direction based on the display, and detect the position by looking at the target image itself. Erroneous detection due to inadvertent mistakes can be reliably eliminated.

In addition, the personal computer 12
Is installed near the operation panel of the propulsion excavator 1, the correction operation using the operation panel can be performed while checking the display on the display screen, so that the operation time can be reduced and the reliability can be improved. Further, if the operation panel and the personal computer 12 are installed outside the starting pit H1, the operator can work in a comfortable posture while securing a wide working space, and thus the workability is improved.

(Other Embodiments) The present invention is not limited to the above-described embodiments, but includes various other embodiments. That is, in the above-described embodiment, the cutting edge position detecting device A is applied to the propulsion excavator 1 of the speeder method, but is not limited to this, and can be applied to, for example, a press-fit type or auger type propulsion excavator. In particular, when the diameter of the propulsion pipe is 80 cm or less, it is difficult for the operator to pass through the propulsion pipe to the excavation head 3 at the front end thereof. Extremely effective.

Further, in the above embodiment, the shape of the reflection target 4 is an isosceles triangle, but is not limited to this. That is, as shown in FIGS. 8A to 8D, for example, various shapes such as a circular shape with one direction cut out, a triangular shape with a central part removed, a square shape with one direction cut out, and a U-shape are illustrated. May be selected as appropriate from the shapes in consideration of compatibility with the image processing algorithm.

Further, in the above embodiment, the operator needs to continuously watch the screen display of the monitor display 30 to monitor the target image.
Based on the position detection result by the personal computer 12, a warning can be issued when the excavation direction deviates from the target direction by a predetermined amount or more. By doing so, the operator does not need to continuously monitor the display screen for a long time, and the operability is greatly improved.

In addition, as shown by a virtual line in FIG. 1, a control device (control means) 31 including a microprocessor or the like for controlling the operation of the propulsion excavator 1 based on the position detection result by the personal computer 12 is provided. That way, you can automatically correct the digging direction,
Labor saving of construction is achieved.

[0062]

As described above, according to the cutting edge position detecting device of the propulsion excavator according to the first aspect of the present invention, the incident light beam is set in the backward direction as a target collimated by the telescope of the theodolite. Since the contrast of the target image in the field of view of the telescope can be made extremely high by using the retroreflecting means for reflecting the light, the position of the cutting edge at a long distance which could not be detected conventionally can be surely detected. In addition, the failure of the target can be reliably avoided, and the inability of the construction to proceed due to the failure of the position detection device can be resolved.

According to the second aspect of the present invention, the direction of the cutting edge can be optimally changed when the excavation direction is corrected.

According to the third aspect of the present invention, a target having an inexpensive and simple configuration can be obtained, and the shape of the target can be easily recognized.

According to the fourth aspect of the invention, by using laser light for the projection optical system, the detectable distance of the cutting edge position detecting device can be further extended.

According to the fifth aspect of the present invention, the easiness of the work is improved, and the time and the reliability of the correction work are improved.

According to the sixth aspect of the present invention, the performance of the imaging means is maximized, and the position of the cutting edge and the direction of the cutting edge can be easily recognized.

According to the seventh aspect of the present invention, inadvertent mistakes by the operator can be reliably eliminated, and the easiness of the work is remarkably improved.

According to the eighth aspect of the present invention, the direction of the propulsion pipe can be corrected even if the target image is not observable.

When the diameter of the propulsion pipe is 80 cm or less as in the ninth aspect, the effect of the present invention is extremely effective.

According to a tenth aspect of the present invention, there is provided the excavation direction management device for a propulsion excavator according to the first and seventh aspects.
The same effects as those of the described invention can be obtained, and the direction of excavation can be automatically corrected, so that labor for the construction can be saved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a cutting edge position detecting device A according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a schematic procedure of a pipe burying work by a speeder method.

FIG. 3 is a front view showing a shape of a reflection target.

FIG. 4 is an explanatory diagram showing a configuration of a laser projection system, an optical system of a telescope, and an enlargement optical system.

FIG. 5 is an explanatory diagram showing how a target image is enlarged.

FIG. 6 is a flowchart illustrating an image processing procedure.

FIG. 7 is an explanatory diagram showing a display example on a display screen.

FIG. 8 is a diagram corresponding to FIG. 3, showing another shape of the reflection target.

FIG. 9 is an explanatory diagram showing a schematic configuration of a conventional cutting edge position detecting device.

[Explanation of symbols]

 Reference Signs List 1 propulsion excavator (excavator) 2 lead pipe (propulsion pipe) 3 drilling head (cutting blade) 4 reflection target (reverse reflection means) 5 theodolite (theodolite) 6 telescope 10 laser projection system (projection optical system) 12 Personal computer (detection means) 15 Semiconductor laser device (laser light) 25 Magnifying optical system 26 CCD camera (imaging means) 31 Control device (control means)

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[Procedure amendment]

[Submission date] June 16, 1999 (1999.6.1
6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

Patent application title: Excavator cutting edge position detecting device and excavation direction management device

[Claims]

2. A cutting edge position detecting apparatus for an excavator according to claim 1, wherein the target is a prism sheet having a predetermined shape capable of recognizing an axial center position of the propulsion pipe and a cutting edge position of the cutting edge. .

3. The method of claim 1 or 2, the cutting edge position detecting device of the excavator, characterized in that the projection optical system is to the laser beam as a light source.

4. The cutting edge position detection of an excavator according to any one of claims 1 to 3 , further comprising imaging means for receiving a target image obtained by a telescope of the theodolite. apparatus.

5. The cutting blade position detecting device for an excavator according to claim 4, wherein an enlargement optical system for enlarging a target image is provided between the telescope and the imaging means.

6. The method according to claim 4 or 5, based on the data of the target image that is input to the imaging unit, the excavator, characterized in that it comprises a detection means for detecting the axial position of at least propulsion tube Cutting edge position detector.

7. The cutting edge position detecting device for an excavator according to claim 6 , further comprising storage means for storing a detection result by the detection means in a time series.

8. In any one of claims 1-7, the cutting edge position detecting device of the excavator, characterized in that the diameter of the propulsion tube is 80cm or less.

9. have propulsion tube cutting edge is provided to excavate the soil to the front end, cutting edges of the front end of the propulsion tube is arranged so as to extend toward the target direction and the front from the rear end side An excavation direction management device for an excavator configured to excavate while pushing forward, wherein the cutting edge position of the cutting edge is off to one side with respect to the axis of the propulsion pipe.
At least the axial position of the propulsion pipe and the cutting
Both positions can be identified corresponding to the cutting edge position of the blade
A target comprising retroreflecting means for reflecting incident light in the reverse direction thereof, and a cutting blade provided near the rear end of the propulsion tube, collimating the target and cutting in the target direction. A projection optical system that is provided near the rear end of the propulsion tube and projects light into the tube along the optical axis of the telescope of the theodolite to irradiate the target; and Imaging means for inputting a target image obtained by a telescope of a ceremony; and at least an axis position of the propulsion tube and a cutting edge position of the cutting blade based on data of the target image input to the imaging means. An excavation direction management device comprising: a detection unit for detecting; and a control unit for controlling the operation of the excavator based on a detection result by the detection unit so that a traveling direction of the propulsion pipe becomes a target direction. .

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting blade position detecting device for detecting the position of a cutting blade at the front end of a propulsion pipe that advances in the soil, for example, in a propulsion excavator used for burying water pipes, and the like. The present invention relates to a digging direction management device that corrects a digging direction of a propulsion pipe to a target direction by using the device.

[0002]

2. Description of the Related Art Conventionally, a so-called small-diameter pipe propulsion method has been generally used for burying relatively small-diameter pipes such as water pipes and gas pipes. In this method, first, two vertical shafts, a starting shaft and a reaching shaft, are dug in the ground where the pipes are to be buried, and then the pipes are buried while excavating the soil from inside the starting shaft toward the reaching shaft. However, there is an advantage that it is hard to hinder traffic even in a situation where digging work is difficult such as in an urban area with heavy traffic. In this method, various methods such as press-fitting method, auger method, and boring method have been established according to the soil properties of the ground and the type of buried pipes. it can.

[0003] More specifically, referring to FIG. 2, a temporary pipe combined type two-step method called a speeder method will be described. In this method, first, a hydraulic propulsion excavator 1 is installed in a starting pit H1. The lead pipe (propulsion pipe) 2 attached to the propulsion excavator 1 is pushed forward while being rotated by a hydraulic mechanism, and is advanced toward the reaching pit H2 while consolidating the soil by the excavation head 3 at the front end of the lead pipe 2. , One after the other at the rear end of the lead tube 2,
Are added and penetrated to the reaching shaft H2 (see FIG. 7A).

Next, a buried pipe 35, a leading cutter 36 and a screw conveyor 37 are provided at the rear end of the last lead pipe 2.
Are rotated in the same manner as the lead pipes 22, 22,. That is, the buried pipe 3
, And screw conveyors 37, 37,... Are sequentially added, while the lead pipes 2, 2,.
While collecting the buried pipes 35, 3 toward the arrival pit H2.
Advance 5, ... At this time, the soil excavated by the leading cutter 36 is removed by screw conveyors 37, 37,
Are discharged through the subsequent buried pipes 35, 35,... (See FIG. 3B). And the top buried pipe 35
Reaches the reaching shaft H2, the leading cutter 36 is collected on the reaching shaft H2 side, and the buried pipes 35, 3 are recovered on the starting shaft H1 side.
The screw conveyors 37, 37,... Are pulled out and sequentially collected, and then the inside of the buried pipes 35, 35,.

As described above, in the speeder method, the lead pipes 2, 2,...
Although it is extremely important to reach 2, the excavating head 3 that advances in the soil receives an unbalanced force from the upper, lower, left, and right grounds, so that if it is released, it will gradually deviate from the target direction. Therefore, usually, a position detecting device for detecting the position of the excavating head 3 is used to constantly monitor and correct the excavating head so as not to leave the target direction.

[0006] Generally, as the position detecting device, a target provided on a drilling head and a theodolite for collimating the target are used.
That is, as shown in FIG. 9, for example, nine LEDs (light emitting diodes) 39, 39,... LED 39 emits yellow light, and
The LED 39 corresponding to the cutting edge position of the excavating head 3 (upper position in the figure) emits red light, and further, other LEDs
39, 39,... Emit green light.

On the other hand, the theodolite (see FIG. 2) is installed in the starting pit H1, and the LEDs 39, 3 are viewed from the rear end of the rearmost lead tube 2 along the axis of the tube.
The target consisting of 9,... Can be collimated. That is, the operator can easily recognize the center position of the excavation head and the position of the cutting edge thereof based on the difference in the emission color of the LED depending on the position of the target.

[0008]

By the way, in recent years, the maximum propulsion distance of the pipe has been extended due to the improvement of the performance of the excavator, and the interval from the starting pit H1 to the reaching pit H2 has been able to be set much longer than before. is there. By doing so, the number of shafts to be dug on the ground can be significantly reduced, so that a remarkably excellent effect can be obtained for shortening the construction period and cost, and furthermore, the construction will not hinder the traffic further. There is expected.

However, in the conventional cutting blade position detecting device, when the distance between the starting pit H1 and the reaching pit H2 becomes longer and the distance of the target from the theodolite becomes longer, the target image in the telescope field of view becomes smaller accordingly. As a result, it is inevitable that the visibility is rapidly reduced.
Therefore, the operator cannot recognize the center position and the cutting edge position of the excavation head, and it becomes difficult to correct the excavation direction accurately.

On the other hand, it is conceivable to enlarge the image of the target by increasing the magnification of the telescope, but in such a case, the entire image is often blurred and difficult to see, and the brightness of the image is increased. , The visibility is not much improved. In addition, even if the brightness of the image is increased by increasing the light emission amount of the LED, only the entire field of view of the telescope becomes bright, and the contrast of the image is not significantly improved.

Further, in the above-mentioned conventional cutting edge position detecting device, an LED is provided on the excavating head so as to emit light, so that the vibration or heat generation of the excavating head causes a defective conduction of an electric circuit or a failure of the LED. There is a fear. In such a case, it is extremely difficult to recover and repair the excavating head that has penetrated deep into the soil, so that it is practically impossible to proceed with the construction normally.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned points, and an object of the present invention is to elaborate the configuration of a cutting edge position detecting device so as to detect a long-distance cutting edge which could not be detected until now. An object of the present invention is to make it possible to reliably detect a position and to eliminate a possibility of work being interrupted due to a failure of a device.

[0013]

In order to achieve the above object, according to the present invention, as a target indicating a cutting edge position, a retroreflecting means for reflecting incident light in the backward direction is used. Then, light was projected from the rear end side of the propulsion tube along the optical axis of the telescope to irradiate the target.

Specifically, the invention according to claim 1 includes a propulsion pipe provided with a cutting blade for excavating in the soil at a front end thereof,
A cutting blade position detecting device for detecting the position of the cutting blade in an excavator in which the propulsion pipe is arranged so that a cutting edge at a front end extends in a target direction and excavates while pushing the propulsion pipe from a rear end side to a front side. It is assumed. And the cutting edge of the cutting blade
The position is offset to one side with respect to the axis of the propulsion pipe.
And shall respectively correspond to and the both the edge positions of the axial position and the cutting edge of at least propulsion tube to the rear end of the cutting edge
A target provided so that the position can be identified, and a theodolite installed near the rear end of the propulsion tube, collimating the target and measuring the position of the cutting blade with respect to the target direction, The target is constituted by retroreflecting means for reflecting incident light in the backward direction, and near the rear end of the propulsion tube, projects light into the tube along the optical axis of the telescope of the theodolite. And a projection optical system for irradiating the target.

Here, the backward direction refers to the direction in which the reflected light beam is superimposed on itself, in other words, the direction in which the reflected light beam travels in the reverse direction along the same path that passed before inversion. For example, a corner cube prism or the like may be used as the retroreflecting means for inverting the light beam.

According to the above arrangement, the light from the projection optical system enters the retroreflecting means as a target along the optical axis of the telescope, is reflected in the backward direction by the retroreflecting means, and is reflected by the telescope. Come back along the optical axis of. That is, almost all the reflected light from the retroreflecting means enters the objective lens of the telescope, so that the image of the target (retroreflecting means) in the telescope field of view has extremely high contrast. This makes it possible to reliably detect a long-distance cutting edge position that could not be detected conventionally.

Further , the target is an axis of the propulsion pipe.
Position and the cutting edge position of the cutting blade, respectively.
Is provided so that the operator can identify the cutting edge.
It can recognize not only the center position but also the direction of the cutting edge.
Wear. This allows the operator to correct the digging direction
It is possible to change the direction of the cutting blade to the optimal direction for correction
Wear.

Further, since the retroreflection means does not require a power supply or an electric circuit unlike an LED and does not itself fail, the electric circuit or the like in the case of using an LED as in the prior art does not fail. Can be avoided reliably, and this can eliminate the possibility that the failure of the position detecting device may cause the progress of the construction to be stopped.

According to a second aspect of the present invention, the target according to the first aspect of the present invention is a prism sheet having a predetermined shape capable of recognizing an axial center position of the propulsion tube and a cutting edge position of the cutting blade. This prism sheet is formed by forming a large number of prisms in a plastic sheet by a fine processing technique. The prism sheet is formed into, for example, a triangular shape to serve as a target. What is necessary is just to attach so that a position may be recognized.

If the prism sheet is used,
An inexpensive and simple target can be obtained. Further, since substantially uniform reflected light is obtained from the entire surface of the prism sheet, recognition of the shape of the target is further facilitated.

According to the third aspect of the present invention, the first or second aspect is provided.
The projection optical system according to any one of the above aspects uses laser light as a light source. As a result, even if the target is at a long distance, the energy density of the light applied to the retroreflecting means can be increased, so that the contrast of the target image in the telescope field of view can be further increased, and thus the cutting edge can be increased. The detectable distance of the position detecting device can be further extended.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, an imaging means for inputting a target image obtained by a telescope of the theodolite is provided. As a result, the target image is input to the imaging means, so that data of the image can be transferred to a separate display device and displayed on the display screen. By doing so, the operator can observe the target in a more comfortable posture, and the workability is improved. Further, when correcting the excavation direction, the work can be performed while checking the display screen, so that the work time can be reduced and the reliability can be improved.

According to a fifth aspect of the present invention, a magnifying optical system for enlarging a target image is provided between the telescope and the imaging means according to the fourth aspect of the present invention. As a result, the target image is enlarged, so that the position of the cutting edge and the direction of the cutting edge can be easily recognized, and accordingly, the correction of the excavation direction can be further facilitated. Further, since a commercially available telescope of the theodolite can be used as it is, it is advantageous in terms of cost.

Further, since the image enlarged by the optical system is inputted to the image pickup means, the performance of the image pickup means can be maximized. It should be noted that although the image becomes darker when enlarged, the contrast is sufficiently high so that there is no problem in visibility.

According to the sixth aspect of the present invention, in the fourth or fifth aspect,
In the invention described in (1), a detection means for detecting at least the axial center position of the propulsion pipe based on the data of the target image input to the imaging means is provided.

Thus, based on the data of the target image input to the imaging means, the detecting means detects the cutting edge position in accordance with an image processing technique such as pattern recognition. In particular, when a prism sheet is used as in the second aspect of the present invention, an image with substantially uniform brightness can be obtained over the entire surface of the prism sheet, so that the accuracy of image recognition is extremely high. If the position detection result by the detection means is displayed on, for example, a display screen, the operator can correct the excavation direction based on the display. Inadvertent mistakes in the detection of can be reliably eliminated.

Further, based on the detection result by the detection means, an alarm can be issued when the cutting edge position deviates from the target direction by a predetermined amount or more, so that the operator can set the cutting edge position. It is not necessary to continuously monitor for a long time, and workability is remarkably improved.

According to a seventh aspect of the present invention, in the fifth aspect of the present invention, a storage unit for storing a detection result by the detection unit in a time series is provided.

That is, for example, when the cutting blade collides with rocks in the soil and largely deviates from the target direction, the target image may move out of the field of view of the telescope, making observation impossible. Therefore, in the present invention, the position detection result by the detection means is stored in chronological order by the storage means. Therefore, even if the target image cannot be observed, the position detection result based on the previous detection result, that is, the trajectory of the target image is used. Thus, the current position of the cutting edge can be estimated. With this,
Even if the target becomes unobservable, the direction of the propulsion pipe can be corrected.

According to the invention described in claim 8 , the diameter of the propulsion pipe in the invention described in any one of claims 1 to 7 is 80.
cm or less. This embodies the size of the propulsion tube. That is, when the diameter of the propulsion pipe is 80 cm or less, it is not easy for the operator to go through the propulsion pipe to the front end thereof. It is extremely effective to be able to accurately detect the position of the cutting edge at the front end and to eliminate the occurrence of failure of the target provided on the cutting edge while staying there.

According to the ninth aspect of the present invention, a propulsion pipe provided with a cutting blade for excavating the soil is provided at the front end, and the propulsion pipe is arranged such that the cutting blade at the front end extends toward a target direction. In addition, it is assumed that an excavating direction management device in an excavator that excavates while pushing forward from a rear end side to a front side. And
The cutting edge position of the cutting blade is off to one side with respect to the axis of the propulsion pipe.
It is assumed that at least the axial position of the propulsion tube and the position of the cutting edge of the cutting blade are respectively set at the rear end of the cutting blade.
And response and provided to both said positions to be identified and the target consisting of reversing reflecting means for reflecting the incident light in the reverse direction, is disposed near the rear end of the propulsion tube, viewing the target A theodolite that measures the position of the cutting blade with respect to the target direction, and is provided near the rear end of the propulsion tube, and projects light into the tube along the optical axis of the telescope of the theodolite to target the target. A projection optical system for irradiating, imaging means to which a target image obtained by the telescope of the theodolite is input, and at least an axial center position and a cutting point of the propulsion tube based on data of the target image input to the imaging means. Blade tip
A configuration is provided that includes a detection unit that detects the position , and a control unit that controls the operation of the excavator based on the detection result by the detection unit so that the traveling direction of the propulsion pipe becomes the target direction.

According to this configuration, the same operation as the first and sixth aspects of the present invention can be obtained, and even if the target is at a long distance, the center position of the cutting blade corresponding to the axial center position of the propulsion tube can be obtained.
Can the cutting edge position of the cutting edge that is offset therefrom in <br/> by Ri確 indeed detected in the detection means, by the excavator control operation based on the detection result, it is possible to automatically correct the direction of drilling .

[0033]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of a cutting edge position detecting device A of an excavator according to an embodiment of the present invention. The cutting edge position detecting device A is used for cutting a buried pipe such as a fume pipe by a speeder method, for example. It is mounted on the propulsion excavator 1 to be buried inside. The propulsion excavator 1 is installed in the starting pit H1 as shown in FIG. 2 and operates by operating hydraulic pressure supplied from a hydraulic pressure supply unit (not shown) installed outside the starting pit H1.

In FIG. 1, reference numerals 2, 2,... Denote lead pipes that first penetrate from the start pit H1 to the destination pit H2 in order to lead the buried pipe. These lead tubes 2, 2, ...
It consists of a stainless steel pipe with a diameter of about 10 cm, and a cutting head (cutting edge) 3 is attached to the front end of the lead pipe 2 at the head, while the rear end of the lead pipe 2 at the tail is in the starting pit H1. It is connected to a hydraulic drive unit (propulsion mechanism) of the installed propulsion excavator 1. And the lead tube 2,2, ...
Are driven forward along this axis while being rotated clockwise about the central axis of the tube. Also, the tip end surface of the excavating head 3 is inclined with respect to the axis of the lead tube 2, while the rear end surface of the excavating head 3 is perpendicular to the axis of the lead tube and faces the inside of the tube. Is provided with a reflection target 4 formed of a prism sheet.

On the other hand, a theodolite (theodolite) 5 is installed in the vicinity of the rear end of the last lead tube 2, and the telescope 6 looks inside the lead tubes 2, 2,. It can be collimated. The theodolite 5 is supported on a gantry 7 at three locations via height adjusting screws, and is supported on the horizontal board 8 so as to be pivotable about a vertical axis. It has a U-shaped support portion 9 that is rotatably supported around an axis, and can collimate the reflection target 4 in the telescopic field of view to measure the horizontal angle and the vertical angle thereof with high accuracy.

The telescope 6 has a laser projection system (projection optical system) for projecting a laser beam forward along the optical axis x.
A laser beam (indicated by an arrow in the figure) emitted from the laser projecting system 10 is reflected by the reflection target 4 and returns along the optical axis x of the telescope 6 to be telescoped. It appears as an image of the reflection target 4 in the field of view. Further, the telescope 6 receives the image of the reflection target 4 and transmits the data of the image to the personal computer 1 installed outside the starting pit H1 by the communication cable 11.
2, an image pickup system 13 for transferring the image data is provided.

As shown in FIG. 3, the reflection target 4 is a prism sheet formed in the shape of an isosceles triangle that is long vertically and attached to the rear end surface of the excavating head 3. In addition, the designated vertex (upper vertex in the figure) 4b facing the bottom is associated with the cutting edge position of the excavating head 3, and goes from the center position 4a to the designated vertex 4b. The pointing direction can be easily identified. As is well known, the prism sheet is formed by forming a large number of prisms in a plastic sheet by a fine processing technique, and, like a corner cube prism or the like, reflects almost all incident light in the backward direction. .

The optical system of the telescope 6 and the laser projection system 10 is configured as shown in FIG. That is, the laser beam output from the semiconductor laser device (laser transmitter) 15 as a light source is first adjusted in divergence angle by a pair of condenser lenses 16, 16, and then deflected by 90 ° by the right-angle prism 17. , Focusing lens 18
, The light is again deflected by 90 degrees by the right-angle prism 19 arranged on the optical axis x of the telescope 6, and the objective lens 2
The light is projected toward the reflection target 4 along the optical axis x of the telescope 6 through the optical axis 0. It is preferable that the diameter of the light beam of the laser beam is set to be slightly larger than the diameter at the front end of the lead tube 2.

The laser beam reflected by the reflection target 4 and returned along the optical axis x of the telescope 6 is condensed by the objective lens 22 of the telescope 6 to form an image of the reflection target 4. . That is, the image of the reflection target 4 is turned upside down and left and right by the roof prism 23, passes through a focusing mirror 24 having a built-in crosshair, is enlarged by an enlargement optical system 25, and is input to a CCD camera (imaging means) 26. You.

The CCD camera 26 moves back and forth and is fixed at an arbitrary position. When the CCD camera 26 is moved forward, the image of the reflection target 4 is changed as shown in FIG. By making the CCD camera 26 recede, the image of the reflection target 4 can be enlarged as shown in FIG. 5B. In addition, the focusing lens 27 is moved along the optical axis in response to the forward or backward movement of the CCD camera 26.
The image of the reflection target 4 is always formed on the imaging surface of the CCD camera 26. In FIG. 4, reference numeral 28 denotes a focusing lens of the telescope 6, and reference numerals 29 and 29 denote CCs from the telescope 6 respectively.
The right-angle prism deflects the laser beam reaching the D camera 26.

The CCD camera 26 transfers the input image data to the personal computer 12 as an NTSC signal. This personal computer 12
Has a dedicated image processing board built-in, and transfers the transferred data at a predetermined cycle (for example, every several hundred milliseconds).
By performing the processing, the center position 4a of the reflection target 4 and the pointing direction thereof are detected. Specifically, FIG.
As shown in the flow shown in (1), in step S1, a signal input from the CCD camera 26 is accepted to acquire image data, and in subsequent step S2, background noise is removed by filtering.

Subsequently, in step S3, the coordinates of three vertices of the isosceles triangle of the image are obtained, and the pattern of the reflection target 4 is recognized based on the coordinates of the vertices. In step S4, the center position 4a of the reflection target 4 is calculated based on the coordinates of the three vertices. In step S5, the length of the base of the isosceles triangle of the image (indicated by an arrow in the figure) is set as the target size. Ask for. Subsequently, in step S6, the distance to the reflection target 4 is calculated based on the target size, and
The shift amount of the center position coordinate calculated in step 4 from the coordinate origin, that is, the shift amount of the target center from the target direction is calculated, and the direction of the designated vertex 4b with respect to the center position 4a is obtained.

Then, in step S7, as shown in FIG. 7, for example, the image of the reflection target 4 after noise removal and the calculation result of the shift amount are output to the monitor display 30 of the personal computer 12 and displayed to the operator. I do.

The processing in each step of the flow of FIG. 6 is realized by executing a program electronically stored in the memory of the personal computer 12 or the ROM of the image processing board by the microprocessor (CPU). . That is, detection means is constituted by the CPU and the image processing board.

Although not shown, the personal computer 12 has a built-in storage device (storage means) such as a hard disk. The storage device stores the displacement of the target center 4a and the direction of the designated vertex 4b detected as described above. The detection results are stored in chronological order.

Next, a method for managing the direction of excavation using the cutting edge position detecting device A will be described.

First, the operator attaches the first lead pipe 2 to the propulsion excavator 1 and checks the image of the reflection target 4 on the monitor display 30 while checking the center position of the image with the center position of the crosshair (coordinate origin). ), That is, the direction of the lead tube 2 is determined so that the center position of the lead tube in the excavation head 3 matches the target direction. Next, the propulsion excavator 1 is operated, and the lead pipe 2
When the lead pipe 2 advances to the full propulsion stroke of the hydraulic mechanism of the propulsion excavator 1,
Then connect the next lead tube 2 to the end and push them again. Then, the above operations are repeatedly executed.

At this time, the image of the reflection target 4 on the screen of the monitor display 30 is ideally gradually rotated clockwise around the center position while the center position coincides with the coordinate origin. However, in practice, the excavating head 3 advancing in the soil is gradually departed from the target direction due to the reaction force from the ground, so that the center position of the image also gradually deviates from the coordinate origin. To go.

Therefore, the operator monitors the image of the reflection target 4 on the display screen, and when the image deviates from the coordinate origin by a predetermined amount or more, for example, as shown in FIG. 7, the operation of the propulsion excavator 1 is temporarily stopped. . While confirming the image on the display screen, the propulsion excavator 1 uses the propulsion excavator 1 until the indicated direction of the image indicates the coordinate origin, that is, until the cutting edge of the excavation head 3 is directed to the target direction.
2. Rotate in place.

Subsequently, the propulsion excavator 1 pushes the lead pipes 2, 2,... Forward without rotating them. In this case, since the excavation head 3 has its tip blade tip surface inclined with respect to the axis of the lead pipe 2, the excavation head 3 advances toward the cutting edge side as a whole.
The excavation direction of the lead pipes 2, 2, ... is corrected so as to approach the target direction.

Further, for example, when the excavating head 3 collides with rocks in the soil and largely deviates from the target direction, the target image moves out of the telescope field of view and becomes unobservable. Reproduces the time-series position detection result stored in the storage device of the personal computer 12, that is, the trajectory of the target image on the monitor display 30, and based on the trajectory, the current position of the unobservable excavation head 3 Is estimated. Then, the excavation direction of the lead pipe 2 can be corrected based on the estimated position of the excavation head 3.

Therefore, according to the cutting edge position detecting device A of this embodiment, the laser beam is projected from the laser projecting system 10 on the starting pit H1 side to the reflection target 4 disposed on the rear end face of the excavating head 3. Thus, even if the reflection target 4 is at a long distance, it is possible to irradiate light having a sufficiently high energy density.
Further, since the reflection target 4 is constituted by a prism sheet, almost all of the laser beam reflected from the reflection target 4 can be incident on the objective lens 22 of the telescope 6. As a result, the image of the reflection target 4 in the telescope field of view becomes extremely high in contrast, and the drilling head 3
Is at a long distance that cannot be detected by conventional devices,
The position can be reliably detected. Therefore, in the propulsion work, the excavation direction can be controlled even if the distance between the start pit H1 and the arrival pit H2 is significantly increased, so that remarkably excellent effects such as shortening of the work period and cost reduction can be obtained.

In addition, since the reflection target 4 can be formed inexpensively and simply by using a prism sheet, and substantially uniform reflected light can be obtained from the entire surface of the reflection target 4, the target image can be more easily recognized. Become. This provides an effective effect particularly when performing image processing. In addition, since the reflection target 4 is illuminated from the starting pit side, and a power source or an electric circuit is not required on the excavation head side, L which has been a concern in the conventional apparatus is not considered.
Failure of the ED, electric circuit, and the like can be reliably avoided.

Further, since the image of the reflection target 4 is enlarged by the magnifying optical system 25 and taken into the CCD camera 26, the performance of the CCD camera 26 can be maximized. In addition, since the image is enlarged, the visibility is improved even on the screen of the monitor display 30, and the position detection accuracy by the image processing is improved.
Although the image of the reflection target 4 becomes darker when enlarged, the contrast is extremely high as described above, so that there is no problem in visibility.

Further, in this embodiment, image processing such as pattern recognition is performed based on the image data captured by the CCD camera 26, and the axial positions of the lead tubes 2, 2,. Is detected and the detection result is displayed on the display screen, so that the operator can correct the excavation direction based on the display, and detect the position by looking at the target image itself. Erroneous detection due to inadvertent mistakes can be reliably eliminated.

In addition, the personal computer 12
Is installed near the operation panel of the propulsion excavator 1, the correction operation using the operation panel can be performed while checking the display on the display screen, so that the operation time can be reduced and the reliability can be improved. Further, if the operation panel and the personal computer 12 are installed outside the starting pit H1, the operator can work in a comfortable posture while securing a wide working space, and thus the workability is improved.

(Other Embodiments) The present invention is not limited to the above-described embodiments, but includes various other embodiments. That is, in the above-described embodiment, the cutting edge position detecting device A is applied to the propulsion excavator 1 of the speeder method, but is not limited to this, and can be applied to, for example, a press-fit type or auger type propulsion excavator. In particular, when the diameter of the propulsion pipe is 80 cm or less, it is difficult for the operator to pass through the propulsion pipe to the excavation head 3 at the front end thereof. Extremely effective.

Further, in the above embodiment, the shape of the reflection target 4 is an isosceles triangle, but is not limited to this. That is, as shown in FIGS. 8A to 8D, for example, various shapes such as a circular shape with one direction cut out, a triangular shape with a central part removed, a square shape with one direction cut out, and a U-shape are illustrated. May be selected as appropriate from the shapes in consideration of compatibility with the image processing algorithm.

Further, in the above embodiment, the operator needs to continuously watch the screen display of the monitor display 30 to monitor the target image.
Based on the position detection result by the personal computer 12, a warning can be issued when the excavation direction deviates from the target direction by a predetermined amount or more. By doing so, the operator does not need to continuously monitor the display screen for a long time, and the operability is greatly improved.

In addition, as shown by a virtual line in FIG. 1, a control device (control means) 31 including a microprocessor or the like for controlling the operation of the propulsion excavator 1 based on the position detection result by the personal computer 12 is provided. That way, you can automatically correct the digging direction,
Labor saving of construction is achieved.

[0062]

As described above, according to the cutting edge position detecting device of the propulsion excavator according to the first aspect of the present invention, the incident light beam is set in the backward direction as a target collimated by the telescope of the theodolite. By using the retroreflecting means to reflect the light to the target, the contrast of the target image in the telescope field of view can be extremely high, so that the center position and the cutting edge position of the long-range cutting blade which could not be detected conventionally can be reliably determined. Can be detected , so that the orientation of the cutting edge can be
Optimally varied modified Ru done. In addition, the failure of the target can be reliably avoided, and the inability of the construction to proceed due to the failure of the position detection device can be resolved.

According to the second aspect of the present invention, a target having an inexpensive and simple configuration can be obtained, and the shape of the target can be easily recognized.

According to the third aspect of the present invention, by using laser light for the projection optical system, the detectable distance of the cutting edge position detecting device can be further extended.

According to the fourth aspect of the present invention, the easiness of the operation is improved, and the time and the reliability of the correction operation are improved.

According to the fifth aspect of the present invention, the performance of the imaging means is maximized, and the position of the cutting blade and the direction of the cutting edge can be easily recognized.

According to the sixth aspect of the present invention, inadvertent mistakes by the operator can be reliably eliminated, and the easiness of the work is remarkably improved.

According to the seventh aspect of the present invention, the direction of the propulsion pipe can be corrected even if the target image cannot be observed.

When the diameter of the propulsion pipe is 80 cm or less as in the invention of claim 8 , the effect of the present invention is extremely effective.

According to the excavation direction management device for a propulsion excavator in the ninth aspect of the invention, the same effects as those of the first and sixth aspects are obtained, and the digging direction can be automatically corrected. In addition, labor can be saved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a cutting edge position detecting device A according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a schematic procedure of a pipe burying work by a speeder method.

FIG. 3 is a front view showing a shape of a reflection target.

FIG. 4 is an explanatory diagram showing a configuration of a laser projection system, an optical system of a telescope, and an enlargement optical system.

FIG. 5 is an explanatory diagram showing how a target image is enlarged.

FIG. 6 is a flowchart illustrating an image processing procedure.

FIG. 7 is an explanatory diagram showing a display example on a display screen.

FIG. 8 is a diagram corresponding to FIG. 3, showing another shape of the reflection target.

FIG. 9 is an explanatory diagram showing a schematic configuration of a conventional cutting edge position detecting device.

[Description of Signs] 1 Propulsion excavator (excavator) 2 Lead pipe (propulsion pipe) 3 Drilling head (cutting blade) 4 Reflection target (reverse reflection means) 5 Theodolite (theodolite) 6 Telescope 10 Laser projection system ( Projection optical system) 12 Personal computer (detection means) 15 Semiconductor laser device (laser light) 25 Magnification optical system 26 CCD camera (imaging means) 31 Control device (control means) ───────────── ────────────────────────────────────────

[Procedure amendment]

[Submission date] September 27, 1999 (September 9, 1999
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

Patent application title: Excavator cutting edge position detecting device and excavation direction management device

[Claims]

2. A cutting edge position detecting apparatus for an excavator according to claim 1, wherein the target is a prism sheet having a predetermined shape capable of recognizing an axial center position of the propulsion pipe and a cutting edge position of the cutting edge. .

3. The method of claim 1 or 2, the cutting edge position detecting device of the excavator, characterized in that the projection optical system is to the laser beam as a light source.

4. The cutting edge position detection of an excavator according to any one of claims 1 to 3 , further comprising imaging means for receiving a target image obtained by a telescope of the theodolite. apparatus.

5. The cutting blade position detecting device for an excavator according to claim 4, wherein an enlargement optical system for enlarging a target image is provided between the telescope and the imaging means.

6. The method according to claim 4 or 5, based on the data of the target image that is input to the imaging unit, the excavator, characterized in that it comprises a detection means for detecting the axial position of at least propulsion tube Cutting edge position detector.

7. The cutting edge position detecting device for an excavator according to claim 6 , further comprising storage means for storing a detection result by the detection means in a time series.

8. In any one of claims 1-7, the cutting edge position detecting device of the excavator, characterized in that the diameter of the propulsion tube is 80cm or less.

9. have propulsion tube cutting edge is provided to excavate the soil to the front end, cutting edges of the front end of the propulsion tube is arranged so as to extend toward the target direction and the front from the rear end side An excavation direction control device for an excavator adapted to excavate while pushing forward, wherein the cutting edge of the cutting edge is inclined with respect to the axis of the propulsion pipe.
Ri, axial position and the switching of the at least propulsion tube to the rear end of the cutting edge
Both positions can be identified corresponding to the cutting edge position of the blade
A target comprising retroreflecting means for reflecting incident light in the reverse direction thereof, and a cutting blade provided near the rear end of the propulsion tube, collimating the target and cutting in the target direction. A projection optical system that is provided near the rear end of the propulsion tube and projects light into the tube along the optical axis of the telescope of the theodolite to irradiate the target; and Imaging means for inputting a target image obtained by a telescope of a ceremony; and at least an axis position of the propulsion tube and a cutting edge position of the cutting blade based on data of the target image input to the imaging means. An excavation direction management device comprising: a detection unit for detecting; and a control unit for controlling the operation of the excavator based on a detection result by the detection unit so that a traveling direction of the propulsion pipe becomes a target direction. .

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting blade position detecting device for detecting the position of a cutting blade at the front end of a propulsion pipe that advances in the soil, for example, in a propulsion excavator used for burying water pipes, and the like. The present invention relates to a digging direction management device that corrects a digging direction of a propulsion pipe to a target direction by using the device.

[0002]

2. Description of the Related Art Conventionally, a so-called small-diameter pipe propulsion method has been generally used for burying relatively small-diameter pipes such as water pipes and gas pipes. In this method, first, two vertical shafts, a starting shaft and a reaching shaft, are dug in the ground where the pipes are to be buried, and then the pipes are buried while excavating the soil from inside the starting shaft toward the reaching shaft. However, there is an advantage that it is hard to hinder traffic even in a situation where digging work is difficult such as in an urban area with heavy traffic. In this method, various methods such as press-fitting method, auger method, and boring method have been established according to the soil properties of the ground and the type of buried pipes. it can.

[0003] More specifically, referring to FIG. 2, a temporary pipe combined type two-step method called a speeder method will be described. In this method, first, a hydraulic propulsion excavator 1 is installed in a starting pit H1. The lead pipe (propulsion pipe) 2 attached to the propulsion excavator 1 is pushed forward while being rotated by a hydraulic mechanism, and is advanced toward the reaching pit H2 while consolidating the soil by the excavation head 3 at the front end of the lead pipe 2. , One after the other at the rear end of the lead tube 2,
Are added and penetrated to the reaching shaft H2 (see FIG. 7A).

Next, a buried pipe 35, a leading cutter 36 and a screw conveyor 37 are provided at the rear end of the last lead pipe 2.
Are rotated in the same manner as the lead pipes 22, 22,. That is, the buried pipe 3
, And screw conveyors 37, 37,... Are sequentially added, while the lead pipes 2, 2,.
While collecting the buried pipes 35, 3 toward the arrival pit H2.
Advance 5, ... At this time, the soil excavated by the leading cutter 36 is removed by screw conveyors 37, 37,
Are discharged through the subsequent buried pipes 35, 35,... (See FIG. 3B). And the top buried pipe 35
Reaches the reaching shaft H2, the leading cutter 36 is collected on the reaching shaft H2 side, and the buried pipes 35, 3 are recovered on the starting shaft H1 side.
The screw conveyors 37, 37,... Are pulled out and sequentially collected, and then the inside of the buried pipes 35, 35,.

As described above, in the speeder method, the lead pipes 2, 2,...
Although it is extremely important to reach 2, the excavating head 3 that advances in the soil receives an unbalanced force from the upper, lower, left, and right grounds, so that if it is released, it will gradually deviate from the target direction. Therefore, usually, a position detecting device for detecting the position of the excavating head 3 is used to constantly monitor and correct the excavating head so as not to leave the target direction.

[0006] Generally, as the position detecting device, a target provided on a drilling head and a theodolite for collimating the target are used.
That is, as shown in FIG. 9, for example, nine LEDs (light emitting diodes) 39, 39,... LED 39 emits yellow light, and
The LED 39 corresponding to the cutting edge position of the excavating head 3 (upper position in the figure) emits red light, and further, other LEDs
39, 39,... Emit green light.

On the other hand, the theodolite (see FIG. 2) is installed in the starting pit H1, and the LEDs 39, 3 are viewed from the rear end of the rearmost lead tube 2 along the axis of the tube.
The target consisting of 9,... Can be collimated. That is, the operator can easily recognize the center position of the excavation head and the position of the cutting edge thereof based on the difference in the emission color of the LED depending on the position of the target.

[0008]

By the way, in recent years, the maximum propulsion distance of the pipe has been extended due to the improvement of the performance of the excavator, and the interval from the starting pit H1 to the reaching pit H2 has been able to be set much longer than before. is there. By doing so, the number of shafts to be dug on the ground can be significantly reduced, so that a remarkably excellent effect can be obtained for shortening the construction period and cost, and furthermore, the construction will not hinder the traffic further. There is expected.

However, in the conventional cutting blade position detecting device, when the distance between the starting pit H1 and the reaching pit H2 becomes longer and the distance of the target from the theodolite becomes longer, the target image in the telescope field of view becomes smaller accordingly. As a result, it is inevitable that the visibility is rapidly reduced.
Therefore, the operator cannot recognize the center position and the cutting edge position of the excavation head, and it becomes difficult to correct the excavation direction accurately.

On the other hand, it is conceivable to enlarge the image of the target by increasing the magnification of the telescope, but in such a case, the entire image is often blurred and difficult to see, and the brightness of the image is increased. , The visibility is not much improved. In addition, even if the brightness of the image is increased by increasing the light emission amount of the LED, only the entire field of view of the telescope becomes bright, and the contrast of the image is not significantly improved.

Further, in the above-mentioned conventional cutting edge position detecting device, an LED is provided on the excavating head so as to emit light, so that the vibration or heat generation of the excavating head causes a defective conduction of an electric circuit or a failure of the LED. There is a fear. In such a case, it is extremely difficult to recover and repair the excavating head that has penetrated deep into the soil, so that it is practically impossible to proceed with the construction normally.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned points, and an object of the present invention is to elaborate the configuration of a cutting edge position detecting device so as to detect a long-distance cutting edge which could not be detected until now. An object of the present invention is to make it possible to reliably detect a position and to eliminate a possibility of work being interrupted due to a failure of a device.

[0013]

In order to achieve the above object, according to the present invention, as a target indicating a cutting edge position, a retroreflecting means for reflecting incident light in the backward direction is used. Then, light was projected from the rear end side of the propulsion tube along the optical axis of the telescope to irradiate the target.

Specifically, the invention according to claim 1 includes a propulsion pipe provided with a cutting blade for excavating in the soil at a front end thereof,
A cutting blade position detecting device for detecting the position of the cutting blade in an excavator in which the propulsion pipe is arranged so that a cutting edge at a front end extends in a target direction and excavates while pushing the propulsion pipe from a rear end side to a front side. It is assumed. And the cutting edge of the cutting blade
The plane shall be inclined with respect to the axis of the propulsion pipe, and at least the axial position of the propulsion pipe and the cutting edge
A target provided in correspondence with each of the cutting edge positions of the propulsion pipe, and disposed near the rear end of the propulsion tube, collimating the target and cutting the target direction. A theodolite for measuring the position of the blade, the target is configured by retroreflecting means for reflecting incident light in the reverse direction, and near the rear end of the propulsion tube, A projection optical system for projecting light into the tube along the optical axis of the telescope of the theodolite and irradiating the target is provided.

Here, the backward direction refers to the direction in which the reflected light beam is superimposed on itself, in other words, the direction in which the reflected light beam travels in the reverse direction along the same path that passed before inversion. For example, a corner cube prism or the like may be used as the retroreflecting means for inverting the light beam.

According to the above arrangement, the light from the projection optical system enters the retroreflecting means as a target along the optical axis of the telescope, is reflected in the backward direction by the retroreflecting means, and is reflected by the telescope. Come back along the optical axis of. That is, almost all the reflected light from the retroreflecting means enters the objective lens of the telescope, so that the image of the target (retroreflecting means) in the telescope field of view has extremely high contrast. This makes it possible to reliably detect a long-distance cutting edge position that could not be detected conventionally.

Further , the target is an axis of the propulsion pipe.
Position and the cutting edge position of the cutting blade, respectively.
Is provided so that the operator can identify the cutting edge.
It can recognize not only the center position but also the direction of the cutting edge.
Wear. This allows the operator to correct the digging direction
It is possible to change the direction of the cutting blade to the optimal direction for correction
Wear.

Further, since the retroreflection means does not require a power supply or an electric circuit unlike an LED and does not itself fail, the electric circuit or the like in the case of using an LED as in the prior art does not fail. Can be avoided reliably, and this can eliminate the possibility that the failure of the position detecting device may cause the progress of the construction to be stopped.

According to a second aspect of the present invention, the target according to the first aspect of the present invention is a prism sheet having a predetermined shape capable of recognizing an axial center position of the propulsion tube and a cutting edge position of the cutting blade. This prism sheet is formed by forming a large number of prisms in a plastic sheet by a fine processing technique. The prism sheet is formed into, for example, a triangular shape to serve as a target. What is necessary is just to attach so that a position may be recognized.

If the prism sheet is used,
An inexpensive and simple target can be obtained. Further, since substantially uniform reflected light is obtained from the entire surface of the prism sheet, recognition of the shape of the target is further facilitated.

According to the third aspect of the present invention, the first or second aspect is provided.
The projection optical system according to any one of the above aspects uses laser light as a light source. As a result, even if the target is at a long distance, the energy density of the light applied to the retroreflecting means can be increased, so that the contrast of the target image in the telescope field of view can be further increased, and thus the cutting edge can be increased. The detectable distance of the position detecting device can be further extended.

According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, an imaging means for inputting a target image obtained by a telescope of the theodolite is provided. As a result, the target image is input to the imaging means, so that data of the image can be transferred to a separate display device and displayed on the display screen. By doing so, the operator can observe the target in a more comfortable posture, and the workability is improved. Further, when correcting the excavation direction, the work can be performed while checking the display screen, so that the work time can be reduced and the reliability can be improved.

According to a fifth aspect of the present invention, a magnifying optical system for enlarging a target image is provided between the telescope and the imaging means according to the fourth aspect of the present invention. As a result, the target image is enlarged, so that the position of the cutting edge and the direction of the cutting edge can be easily recognized, and accordingly, the correction of the excavation direction can be further facilitated. Further, since a commercially available telescope of the theodolite can be used as it is, it is advantageous in terms of cost.

Further, since the image enlarged by the optical system is inputted to the image pickup means, the performance of the image pickup means can be maximized. It should be noted that although the image becomes darker when enlarged, the contrast is sufficiently high so that there is no problem in visibility.

According to the sixth aspect of the present invention, in the fourth or fifth aspect,
In the invention described in (1), a detection means for detecting at least the axial center position of the propulsion pipe based on the data of the target image input to the imaging means is provided.

Thus, based on the data of the target image input to the imaging means, the detecting means detects the cutting edge position in accordance with an image processing technique such as pattern recognition. In particular, when a prism sheet is used as in the second aspect of the present invention, an image with substantially uniform brightness can be obtained over the entire surface of the prism sheet, so that the accuracy of image recognition is extremely high. If the position detection result by the detection means is displayed on, for example, a display screen, the operator can correct the excavation direction based on the display. Inadvertent mistakes in the detection of can be reliably eliminated.

Further, based on the detection result by the detection means, an alarm can be issued when the cutting edge position deviates from the target direction by a predetermined amount or more, so that the operator can set the cutting edge position. It is not necessary to continuously monitor for a long time, and workability is remarkably improved.

According to a seventh aspect of the present invention, in the fifth aspect of the present invention, a storage unit for storing a detection result by the detection unit in a time series is provided.

That is, for example, when the cutting blade collides with rocks in the soil and largely deviates from the target direction, the target image may move out of the field of view of the telescope, making observation impossible. Therefore, in the present invention, the position detection result by the detection means is stored in chronological order by the storage means. Therefore, even if the target image cannot be observed, the position detection result based on the previous detection result, that is, the trajectory of the target image is used. Thus, the current position of the cutting edge can be estimated. With this,
Even if the target becomes unobservable, the direction of the propulsion pipe can be corrected.

According to the invention described in claim 8 , the diameter of the propulsion pipe in the invention described in any one of claims 1 to 7 is 80.
cm or less. This embodies the size of the propulsion tube. That is, when the diameter of the propulsion pipe is 80 cm or less, it is not easy for the operator to go through the propulsion pipe to the front end thereof. It is extremely effective to be able to accurately detect the position of the cutting edge at the front end and to eliminate the occurrence of failure of the target provided on the cutting edge while staying there.

According to the ninth aspect of the present invention, a propulsion pipe provided with a cutting blade for excavating the soil is provided at the front end, and the propulsion pipe is arranged such that the cutting blade at the front end extends toward a target direction. In addition, it is assumed that an excavating direction management device in an excavator that excavates while pushing forward from a rear end side to a front side. And
The cutting edge of the cutting edge is inclined with respect to the axis of the propulsion pipe.
And shall respectively correspond to and the both the edge positions of the axial position and the cutting edge of at least propulsion tube to the rear end of the cutting edge
A target that is provided so as to be identifiable and that includes retroreflecting means for reflecting incident light in the backward direction; and a target installed near the rear end of the propulsion pipe, collimating the target and aiming in the target direction. A theodolite that measures the position of the cutting blade with respect to a projection optical system that is provided near the rear end of the propulsion tube and that irradiates the target by projecting light into the tube along the optical axis of the telescope of the theodolite. Imaging means for inputting a target image obtained by the telescope of the theodolite, and detecting at least the axial position of the propulsion pipe and the cutting edge position of the cutting edge based on data of the target image input to the imaging means. And a control means for controlling the operation of the excavator based on the detection result by the detection means so that the traveling direction of the propulsion pipe becomes the target direction.

According to this configuration, the same operation as the first and sixth aspects of the present invention can be obtained, and even if the target is at a long distance, the center position of the cutting blade corresponding to the axial center position of the propulsion tube can be obtained.
There and Ri by the detection means and the cutting edge position in a different position
You to securely detected by the excavator control operation based on the detection result, it is possible to automatically correct the direction of drilling.

[0033]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of a cutting edge position detecting device A of an excavator according to an embodiment of the present invention. The cutting edge position detecting device A is used for cutting a buried pipe such as a fume pipe by a speeder method, for example. It is mounted on the propulsion excavator 1 to be buried inside. The propulsion excavator 1 is installed in the starting pit H1 as shown in FIG. 2 and operates by operating hydraulic pressure supplied from a hydraulic pressure supply unit (not shown) installed outside the starting pit H1.

In FIG. 1, reference numerals 2, 2,... Denote lead pipes that first penetrate from the start pit H1 to the destination pit H2 in order to lead the buried pipe. These lead tubes 2, 2, ...
It consists of a stainless steel pipe with a diameter of about 10 cm, and a cutting head (cutting edge) 3 is attached to the front end of the lead pipe 2 at the head, while the rear end of the lead pipe 2 at the tail is in the starting pit H1. It is connected to a hydraulic drive unit (propulsion mechanism) of the installed propulsion excavator 1. And the lead tube 2,2, ...
Are driven forward along this axis while being rotated clockwise about the central axis of the tube. Also, the tip end surface of the excavating head 3 is inclined with respect to the axis of the lead tube 2, while the rear end surface of the excavating head 3 is perpendicular to the axis of the lead tube and faces the inside of the tube. Is provided with a reflection target 4 formed of a prism sheet.

On the other hand, a theodolite (theodolite) 5 is installed in the vicinity of the rear end of the last lead tube 2, and the telescope 6 looks inside the lead tubes 2, 2,. It can be collimated. The theodolite 5 is supported on a gantry 7 at three locations via height adjusting screws, and is supported on the horizontal board 8 so as to be pivotable about a vertical axis. It has a U-shaped support portion 9 that is rotatably supported around an axis, and can collimate the reflection target 4 in the telescopic field of view to measure the horizontal angle and the vertical angle thereof with high accuracy.

The telescope 6 has a laser projection system (projection optical system) for projecting a laser beam forward along the optical axis x.
A laser beam (indicated by an arrow in the figure) emitted from the laser projecting system 10 is reflected by the reflection target 4 and returns along the optical axis x of the telescope 6 to be telescoped. It appears as an image of the reflection target 4 in the field of view. Further, the telescope 6 receives the image of the reflection target 4 and transmits the data of the image to the personal computer 1 installed outside the starting pit H1 by the communication cable 11.
2, an image pickup system 13 for transferring the image data is provided.

As shown in FIG. 3, the reflection target 4 is a prism sheet formed in the shape of an isosceles triangle that is long vertically and attached to the rear end surface of the excavating head 3. In addition, the designated vertex (upper vertex in the figure) 4b facing the bottom is associated with the cutting edge position of the excavating head 3, and goes from the center position 4a to the designated vertex 4b. The pointing direction can be easily identified. As is well known, the prism sheet is formed by forming a large number of prisms in a plastic sheet by a fine processing technique, and, like a corner cube prism or the like, reflects almost all incident light in the backward direction. .

The optical system of the telescope 6 and the laser projection system 10 is configured as shown in FIG. That is, the laser beam output from the semiconductor laser device (laser transmitter) 15 as a light source is first adjusted in divergence angle by a pair of condenser lenses 16, 16, and then deflected by 90 ° by the right-angle prism 17. , Focusing lens 18
, The light is again deflected by 90 degrees by the right-angle prism 19 arranged on the optical axis x of the telescope 6, and the objective lens 2
The light is projected toward the reflection target 4 along the optical axis x of the telescope 6 through the optical axis 0. It is preferable that the diameter of the light beam of the laser beam is set to be slightly larger than the diameter at the front end of the lead tube 2.

The laser beam reflected by the reflection target 4 and returned along the optical axis x of the telescope 6 is condensed by the objective lens 22 of the telescope 6 to form an image of the reflection target 4. . That is, the image of the reflection target 4 is turned upside down and left and right by the roof prism 23, passes through a focusing mirror 24 having a built-in crosshair, is enlarged by an enlargement optical system 25, and is input to a CCD camera (imaging means) 26. You.

The CCD camera 26 moves back and forth and is fixed at an arbitrary position. When the CCD camera 26 is moved forward, the image of the reflection target 4 is changed as shown in FIG. By making the CCD camera 26 recede, the image of the reflection target 4 can be enlarged as shown in FIG. 5B. In addition, the focusing lens 27 is moved along the optical axis in response to the forward or backward movement of the CCD camera 26.
The image of the reflection target 4 is always formed on the imaging surface of the CCD camera 26. In FIG. 4, reference numeral 28 denotes a focusing lens of the telescope 6, and reference numerals 29 and 29 denote CCs from the telescope 6 respectively.
The right-angle prism deflects the laser beam reaching the D camera 26.

The CCD camera 26 transfers the input image data to the personal computer 12 as an NTSC signal. This personal computer 12
Has a dedicated image processing board built-in, and transfers the transferred data at a predetermined cycle (for example, every several hundred milliseconds).
By performing the processing, the center position 4a of the reflection target 4 and the pointing direction thereof are detected. Specifically, FIG.
As shown in the flow shown in (1), in step S1, a signal input from the CCD camera 26 is accepted to acquire image data, and in subsequent step S2, background noise is removed by filtering.

Subsequently, in step S3, the coordinates of three vertices of the isosceles triangle of the image are obtained, and the pattern of the reflection target 4 is recognized based on the coordinates of the vertices. In step S4, the center position 4a of the reflection target 4 is calculated based on the coordinates of the three vertices. In step S5, the length of the base of the isosceles triangle of the image (indicated by an arrow in the figure) is set as the target size. Ask for. Subsequently, in step S6, the distance to the reflection target 4 is calculated based on the target size, and
The shift amount of the center position coordinate calculated in step 4 from the coordinate origin, that is, the shift amount of the target center from the target direction is calculated, and the direction of the designated vertex 4b with respect to the center position 4a is obtained.

Then, in step S7, as shown in FIG. 7, for example, the image of the reflection target 4 after noise removal and the calculation result of the shift amount are output to the monitor display 30 of the personal computer 12 and displayed to the operator. I do.

The processing in each step of the flow of FIG. 6 is realized by executing a program electronically stored in the memory of the personal computer 12 or the ROM of the image processing board by the microprocessor (CPU). . That is, detection means is constituted by the CPU and the image processing board.

Although not shown, the personal computer 12 has a built-in storage device (storage means) such as a hard disk. The storage device stores the displacement of the target center 4a and the direction of the designated vertex 4b detected as described above. The detection results are stored in chronological order.

Next, a method for managing the direction of excavation using the cutting edge position detecting device A will be described.

First, the operator attaches the first lead pipe 2 to the propulsion excavator 1 and checks the image of the reflection target 4 on the monitor display 30 while checking the center position of the image with the center position of the crosshair (coordinate origin). ), That is, the direction of the lead tube 2 is determined so that the center position of the lead tube in the excavation head 3 matches the target direction. Next, the propulsion excavator 1 is operated, and the lead pipe 2
When the lead pipe 2 advances to the full propulsion stroke of the hydraulic mechanism of the propulsion excavator 1,
Then connect the next lead tube 2 to the end and push them again. Then, the above operations are repeatedly executed.

At this time, the image of the reflection target 4 on the screen of the monitor display 30 is ideally gradually rotated clockwise around the center position while the center position coincides with the coordinate origin. However, in practice, the excavating head 3 advancing in the soil is gradually departed from the target direction due to the reaction force from the ground, so that the center position of the image also gradually deviates from the coordinate origin. To go.

Therefore, the operator monitors the image of the reflection target 4 on the display screen, and when the image deviates from the coordinate origin by a predetermined amount or more, for example, as shown in FIG. 7, the operation of the propulsion excavator 1 is temporarily stopped. . While checking the image on the display screen, the propulsion excavator 1 uses the lead pipe until the pointing direction of the image indicates the coordinate origin, that is, until the cutting edge position of the drilling head 3 is directed to the target direction. 2, 2, ... are rotated on the spot.

Subsequently, the propulsion excavator 1 pushes the lead pipes 2, 2,... Forward without rotating them. In this case, since the tip of the excavating head 3 is slanted with respect to the axis of the lead pipe 2, the excavating head 3 generally advances toward the cutting edge position side. The excavation directions of 2, 2, ... are corrected so as to approach the target direction.

Further, for example, when the excavating head 3 collides with rocks in the soil and largely deviates from the target direction, the target image moves out of the telescope field of view and becomes unobservable. Reproduces the time-series position detection result stored in the storage device of the personal computer 12, that is, the trajectory of the target image on the monitor display 30, and based on the trajectory, the current position of the unobservable excavation head 3 Is estimated. Then, the excavation direction of the lead pipe 2 can be corrected based on the estimated position of the excavation head 3.

Therefore, according to the cutting edge position detecting device A of this embodiment, the laser beam is projected from the laser projecting system 10 on the starting pit H1 side to the reflection target 4 disposed on the rear end face of the excavating head 3. Thus, even if the reflection target 4 is at a long distance, it is possible to irradiate light having a sufficiently high energy density.
Further, since the reflection target 4 is constituted by a prism sheet, almost all of the laser beam reflected from the reflection target 4 can be incident on the objective lens 22 of the telescope 6. As a result, the image of the reflection target 4 in the telescope field of view becomes extremely high in contrast, and the drilling head 3
Is at a long distance that cannot be detected by conventional devices,
The position can be reliably detected. Therefore, in the propulsion work, the excavation direction can be controlled even if the distance between the start pit H1 and the arrival pit H2 is significantly increased, so that remarkably excellent effects such as shortening of the work period and cost reduction can be obtained.

In addition, since the reflection target 4 can be formed inexpensively and simply by using a prism sheet, and substantially uniform reflected light can be obtained from the entire surface of the reflection target 4, the target image can be more easily recognized. Become. This provides an effective effect particularly when performing image processing. In addition, since the reflection target 4 is illuminated from the starting pit side, and a power source or an electric circuit is not required on the excavation head side, L which has been a concern in the conventional apparatus is not considered.
Failure of the ED, electric circuit, and the like can be reliably avoided.

Further, since the image of the reflection target 4 is enlarged by the magnifying optical system 25 and taken into the CCD camera 26, the performance of the CCD camera 26 can be maximized. In addition, since the image is enlarged, the visibility is improved even on the screen of the monitor display 30, and the position detection accuracy by the image processing is improved.
Although the image of the reflection target 4 becomes darker when enlarged, the contrast is extremely high as described above, so that there is no problem in visibility.

Further, in this embodiment, image processing such as pattern recognition is performed based on the image data captured by the CCD camera 26, and the axial positions of the lead tubes 2, 2,. Is detected and the detection result is displayed on the display screen, so that the operator can correct the excavation direction based on the display, and detect the position by looking at the target image itself. Erroneous detection due to inadvertent mistakes can be reliably eliminated.

In addition, the personal computer 12
Is installed near the operation panel of the propulsion excavator 1, the correction operation using the operation panel can be performed while checking the display on the display screen, so that the operation time can be reduced and the reliability can be improved. Further, if the operation panel and the personal computer 12 are installed outside the starting pit H1, the operator can work in a comfortable posture while securing a wide working space, and thus the workability is improved. (Other Embodiments)
The present invention is not limited to the above embodiments, but includes various other embodiments. That is, in the above-described embodiment, the cutting edge position detecting device A is applied to the propulsion excavator 1 of the speeder method, but is not limited to this, and can be applied to, for example, a press-fit type or auger type propulsion excavator. In particular, when the diameter of the propulsion pipe is 80 cm or less, the operator passes through the propulsion pipe and cuts the excavating head 3 at the front end thereof.
Since it is difficult to go to the point, the effect of the present invention is extremely effective in such a case.

Further, in the above embodiment, the shape of the reflection target 4 is an isosceles triangle, but is not limited to this. That is, as shown in FIGS. 8A to 8D, for example, various shapes such as a circular shape with one direction cut out, a triangular shape with a central part removed, a square shape with one direction cut out, and a U-shape are illustrated. May be selected as appropriate from the shapes in consideration of compatibility with the image processing algorithm.

Further, in the above embodiment, the operator needs to continuously monitor the screen display of the monitor display 30 to monitor the target image.
Based on the position detection result by the personal computer 12, a warning can be issued when the excavation direction deviates from the target direction by a predetermined amount or more. By doing so, the operator does not need to continuously monitor the display screen for a long time, and the operability is greatly improved.

In addition, as shown by a virtual line in FIG. 1, a control device (control means) 31 including a microprocessor or the like for controlling the operation of the propulsion excavator 1 based on the position detection result by the personal computer 12 is provided. That way, you can automatically correct the digging direction,
Labor saving of construction is achieved.

[0061]

As described above, according to the cutting edge position detecting device of the propulsion excavator according to the first aspect of the present invention, the incident light beam is set in the backward direction as a target collimated by the telescope of the theodolite. By using the retroreflecting means to reflect the light to the target, the contrast of the target image in the telescope field of view can be extremely high, so that the center position and the cutting edge position of the long-range cutting blade which could not be detected conventionally can be reliably determined. Can be detected , so that the orientation of the cutting edge can be
Optimally varied modified Ru done. In addition, the failure of the target can be reliably avoided, and the inability of the construction to proceed due to the failure of the position detection device can be resolved.

According to the second aspect of the present invention, a target having an inexpensive and simple configuration can be obtained, and the shape of the target can be easily recognized.

According to the third aspect of the invention, by using laser light for the projection optical system, the detectable distance of the cutting edge position detecting device can be further extended.

According to the fourth aspect of the present invention, the easiness of the work is improved, and the time and the reliability of the correction work are improved.

According to the fifth aspect of the present invention, the performance of the imaging means is maximized, and the position of the cutting edge and the direction of the cutting edge can be easily recognized.

According to the sixth aspect of the present invention, inadvertent mistakes by the operator can be reliably eliminated, and the easiness of the work is remarkably improved.

[0067] In the present invention of claim 7, wherein, be made to the target image is unobservable, can modify the direction of the propulsion tube.

When the diameter of the propulsion pipe is 80 cm or less as in the invention of claim 8 , the effect of the present invention is extremely effective.

According to the excavation direction management device for a propulsion excavator according to the ninth aspect, the same effects as those of the first and sixth aspects can be obtained, and the excavation direction can be automatically corrected. In addition, labor can be saved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a cutting edge position detecting device A according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a schematic procedure of a pipe burying work by a speeder method.

FIG. 3 is a front view showing a shape of a reflection target.

FIG. 4 is an explanatory diagram showing a configuration of a laser projection system, an optical system of a telescope, and an enlargement optical system.

FIG. 5 is an explanatory diagram showing how a target image is enlarged.

FIG. 6 is a flowchart illustrating an image processing procedure.

FIG. 7 is an explanatory diagram showing a display example on a display screen.

FIG. 8 is a diagram corresponding to FIG. 3, showing another shape of the reflection target.

FIG. 9 is an explanatory diagram showing a schematic configuration of a conventional cutting edge position detecting device.

[Description of Signs] 1 Propulsion excavator (excavator) 2 Lead pipe (propulsion pipe) 3 Drilling head (cutting blade) 4 Reflection target (reverse reflection means) 5 Theodolite (theodolite) 6 Telescope 10 Laser projection system ( Projection optical system) 12 Personal computer (detection means) 15 Semiconductor laser device (laser light) 25 Magnification optical system 26 CCD camera (imaging means) 31 Control device (control means)

Claims (10)

[Claims] 1. A propulsion pipe provided with a cutting blade for excavating in the soil at a front end thereof, wherein the propulsion pipe is disposed so that a cutting blade at a front end extends in a target direction, and is disposed from a rear end side to a front side. A cutting edge position detecting device for detecting the position of the cutting edge in an excavator adapted to excavate while pushing forward, provided at a rear end of the cutting edge so as to correspond at least to the axial center position of the propulsion pipe. And a theodolite located near the rear end of the propulsion tube, collimating the target and measuring the position of the cutting blade with respect to the target direction. In the vicinity of the rear end of the propulsion tube, a projection optical system that projects light into the tube along the optical axis of the telescope of the theodolite and irradiates the target is provided near the rear end of the propulsion tube. Drilling characterized by being provided Cutting edge position detection device. 2. The target according to claim 1, wherein the target is constituted by retroreflecting means respectively corresponding to the axial center position of the propulsion tube and the cutting edge position of the cutting blade and provided so as to be distinguishable from each other. Excavator cutting edge position detector. 3. A cutting blade position detecting device for an excavator according to claim 1, wherein the target is a prism sheet having a predetermined shape capable of recognizing an axial center position of the propulsion pipe and a cutting edge position of the cutting blade. . 4. A cutting edge position detecting device for an excavator according to claim 1, wherein the projection optical system uses laser light as a light source. 5. The cutting edge position detection of an excavator according to claim 1, further comprising an imaging unit for inputting a target image obtained by a telescope of the theodolite. apparatus. 6. An excavator cutting edge position detecting apparatus according to claim 5, wherein an enlargement optical system for enlarging a target image is provided between the telescope and the imaging means. 7. The excavator according to claim 5, further comprising: a detecting unit configured to detect at least an axial center position of the propulsion pipe based on data of the target image input to the imaging unit. Cutting edge position detector. 8. The cutting blade position detecting device for an excavator according to claim 7, further comprising storage means for storing a detection result by the detection means in a time series. 9. The cutting blade position detecting device for an excavator according to claim 1, wherein the diameter of the propulsion pipe is 80 cm or less. 10. A propulsion pipe provided at a front end thereof with a cutting blade for excavating in the soil, wherein the propulsion pipe is arranged so that a cutting edge at a front end extends in a target direction, and is disposed from a rear end side to a front side. An excavation direction management device in an excavator that excavates while pushing forward, and is provided at a rear end of the cutting blade so as to correspond to at least the axial center position of the propulsion pipe, and transmits incident light in the backward direction. A target comprising retro-reflective means for reflecting light toward the rear end of the propulsion pipe, a theodolite for collimating the target and measuring the position of the cutting blade with respect to the target direction, A projection optical system that is provided near the rear end and projects the target by projecting into the tube along the optical axis of the telescope of the theodolite, and a target image obtained by the telescope of the theodolite is input. Imaging means; and the imaging means Detecting means for detecting at least the axial center position of the propulsion pipe based on the data of the input target image; and, based on a detection result by the detection means, the excavator so that the traveling direction of the propulsion pipe becomes the target direction. An excavation direction management device, comprising: control means for performing operation control.