JPH07102896A - Tail clearance measuring device - Google Patents

Abstract

PURPOSE:To measure the tail clearance at a desired position in the peripheral direction of a segment, by installing the abutting part of a holder by abutting at two points on the inner surface of the segment, and angle measuring a distance sensor so as to position the distance sensor. CONSTITUTION:The end la of a holder 1 is abutted to the inner surface of a segment c at two points P and P, the side surface 2 as of a magnet main body 2a is abutted to the end face of the segment c, and a magnet switch 2b is closed to contact magnetically the magnet main body 2a to the end face of the segment c, so as to position a distance sensor 3. And when such a setting is made, the distance sensor 3 is positioned to a desired setting position of the segment c by a level 4 and the angular scale 4b of the end face 1b of the holder 1. Then, by operating a measuring device, a measurement signal as to the tail clearance is output from the distance sensor 3, and the tail clearance is displayed on a display 6. When the measuring device is operated once, the tail clearance X at all the times in the excavation is made possible to measure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tail clearance measuring device for measuring a tail clearance which is a gap between an inner surface of a tail plate and an outer surface of a segment in a shield machine.

[0002]

2. Description of the Related Art When excavating an underground pit with a shield machine, a shield jack is used to apply thrust to the shield main body, and a cutter in front of the shield main body is used to excavate a cutting face to advance the underground pit. After excavating the underground pit of a predetermined unit length in this manner, the new segment is connected to the existing segment lined on the peripheral wall of the underground pit already excavated, and the segment is annularly assembled on the inner surface of the tail plate at the rear of the shield body. After assembling the new segment, the shield jack is used to again apply thrust to the shield body to similarly excavate an underground pit of a predetermined unit length, and the new segment is assembled in the same manner. When excavating an underground mine by a shield machine, such a process is repeated many times. When advancing the excavation, it is necessary to constantly monitor whether the shield excavator goes straight along the preset excavation line as planned or is curved, but the monitoring is done by the shield excavator. The tail clearance, which is the gap between the inner surface of the tail plate and the outer surface of the segment, is measured. For example, if the shield machine is going straight as planned, the measurement results of the tail clearances at the left and right or top and bottom symmetrical positions will be the same, and if not, the measurement results will be different. . Whether or not the shield machine is traveling along the excavation line as specified can also be determined by knowing the tilting direction of the shield body from the relationship of the tail clearance measurement values at each measurement point. it can. In this way, the tail clearance measuring device is installed in the shield machine to monitor whether or not the shield machine is excavating along the excavation line as planned. It is a device that measures the tail clearance with the outer surface of the segment.

As a conventional technique related to this tail clearance measuring device, a technique described in Japanese Utility Model Laid-Open No. 2-116600 is known as a known technique. Looking at the technology disclosed in this publication, first of all,
In the figure, as a conventional technique, a U-shaped mounting body for positioning over a flange portion of a segment, and a measuring instrument as a contact type distance measuring sensor which is mounted on the mounting body and is composed of a potentiometer. And a lock pin which is also attached to the attachment body and which is engaged with and disengaged from the bolt hole of the segment flange by operating the handle. When using this measuring device, the U-shaped mounting body is positioned across the flange portion at a position corresponding to the bolt hole of the segment flange portion, and
The lock pin attached to the attachment body is engaged with the bolt hole by operating the handle. In this state, the measuring device as the contact type distance measuring sensor is positioned and fixed at the predetermined position, so that the tail clearance is maintained while the rollers as the contactors are in contact with the inner surface of the tail plate. It can be measured electrically. However, this conventional tail clearance measuring device (hereinafter referred to as "conventional device") has an advantage in that the tail clearance can be continuously measured without requiring labor during excavation, but Since the method of engaging the lock pin with the bolt hole is adopted, troublesome replacement work is required every time a new segment is assembled on the inner surface of the tail plate, and it is used only for the type of segment that has a flange According to the above publication, it has the drawback that it cannot
A tail clearance measuring device (hereinafter referred to as "improved conventional device"), which is an improved version of this conventional device, is proposed and shown in Figs. 1 to 5. This improved conventional device consists of a body frame that is installed on the inner surface of the tail plate so as to be movable in the tunnel axis direction through a segment front end alignment jack, and is formed on this body frame for segment front end alignment. Attached to the segment front end face abutting part that can be brought into contact with the segment front end face by the extension operation of the jack and the body frame, through the segment inner face alignment jack, movably in the tunnel radial direction, for segment inner face alignment With a pressing plate that can be brought into contact with the inner surface of the segment by the extension operation of the jack, and a measurement sensor provided on the body frame that detects the relative distance to the inner surface of the tail plate at the position where this pressing plate contacts the inner surface of the segment, and the measuring sensor. Tail clear based on detected relative distance And an arithmetic unit that calculates and outputs Nsu. Since the improved conventional device has such a configuration,
Extend the segment front end alignment jack to bring the segment front end face contact part into contact with the segment front end face, and then extend the segment inner face alignment jack to bring the pressing plate into contact with the segment inner face, thus positioning the body frame. In this state, the measurement sensor can detect the relative distance to the inner surface of the tail plate, and the arithmetic device can calculate the tail clearance based on the relative distance and output the calculated tail clearance to the display device or the like. According to this improved conventional device, when assembling a new segment on the inner surface of the tail plate, it is only necessary to contract both the segment inner surface alignment jack and the segment front end alignment jack to perform the assembly work. The main body frame can be retracted so that it does not get in the way, and when reassembling the tail clearance after assembling the new segment, extend each of these jacks in sequence and repeat the same operation as described above. Therefore, like the conventional device,
It is said that there is no need for troublesome replacement work each time a new segment is assembled. Further, since it employs a method in which the segment front end face contact portion and the pressing plate are brought into contact with the front end face and inner face of the segment to position them, it is said that they can be used for all types of segments.

[0004]

The tail clearance measuring device measures the tail clearance at each point during the excavation of the shield machine to detect the situation in the excavation direction such as the change in the excavation direction during bending. However, in order to perform the detection quickly and accurately, it is necessary to be able to perform the measurement of the tail clearance in real time at the measurement point that requires it. In order to meet these demands, the tail clearance measuring device can be set accurately and easily at any position in the set segment circumferential direction when setting it. It is desirable to do. In addition, the inside of the shield machine is narrow for work, and since many devices such as various jacks, soil discharging devices, various pipes are densely packed, there is a space limitation,
Even if the tail clearance measuring device is set, it is desirable that the position where the tail clearance measuring device is set has a degree of freedom. Even from such a request, the tail clearance measuring device can be accurately positioned at an arbitrary set position and easily set. It is necessary to be able to do it. However, none of the conventional device and the improved conventional device described in the above publication can be easily set at an arbitrary set position in the circumferential direction of the segment. That is, in the conventional device, when setting this, since the lock pin is engaged with the bolt hole of the segment flange portion, it is set only at the circumferential position of the segment where the bolt hole is located. In addition, the lock pin cannot be easily set in a narrow work space in the shield body, because the lock pin needs to be aligned with the bolt hole. Further, in the improved conventional device, the main body frame provided with the measurement sensor is fixedly installed on the shield main body side through the segment front end alignment jack, so that only one preset tail clearance is set. It cannot be measured. That is, with the apparatus shown in FIGS. 1 (1) and 1 (2) of the above publication, only the tail clearance at the circumferential top portion of the segment can be measured.

The present invention is intended to solve such a basic problem in the prior art, and enables accurate setting at any set position in the circumferential direction of the segment so that the segment can be accurately set in the circumferential direction. It is an object of the present invention to provide a tail clearance measuring device having compatibility, which enables measurement of a tail clearance at a desired setting point and also allows easy setting thereof.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a tail clearance measuring device for measuring a tail clearance which is a gap between an inner surface of a tail plate and an outer surface of a segment in a shield machine. ,
A holder having a contact portion capable of contacting at least two points with respect to the inner surface of the segment; a segment end surface contact member which is provided in the holder and can be detachably attached to the end surface of the segment; A non-contact type distance sensor arranged so that the distance between the contact part and the inner surface of the tail plate can be measured at the position where the contact part contacts the inner surface of the segment, and the contact part of the holder contacts the inner surface of the segment. And an angle measuring means for measuring the position of the segment in the circumferential direction of the segment. ”Are provided by the tail clearance measuring device as set forth in the claims.

[0007]

Since the tail clearance measuring device of the present invention has such a structure, when it is used, after the abutting portion of the holder is brought into contact with the inner surface of the segment at two points, While maintaining this contact state, the segment end face contact member is attached to the end face of the segment by contacting the end face of the segment. As a result, the distance sensor is fixedly positioned in a fixed radial and axial position with respect to the segment. In this way, the measuring device of the present invention is set in a segment. When performing the setting, it is possible to accurately position and set the segment at a desired position in the circumferential direction of the segment by using the angle measuring means. it can.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of a main part of a shield machine, showing a state in which a tail clearance measuring device according to an embodiment of the present invention is attached to an end of a segment, and FIG.
FIG. 1A is an enlarged view of FIG. 1, FIG. 3 is an arrow view of FIG. 2 seen from the direction of arrow A, FIG. 4 is an arrow view of BB of FIG. 3, and FIG. 5 is an arrow of CC of FIG. FIG. 6 and FIG. 6 are enlarged views of part A in FIG.

First, the main parts of the shield machine related to the present invention will be briefly described. In the figure, a is a shield main body having a cutter at the front part and propelled by a shield jack d (see FIG. 3), and b is this shield main body. The tail plate at the rear of the shield body a and c are segments for lining the underground pit excavated by the shield body a. This segment c
After excavating the underground pit by a unit length by the shield body a, is assembled in an annular shape on the inner surface of the tail plate b at the rear portion of the shield body a. In this embodiment, the segment c is made of steel.

Next, the tail clearance measuring device according to the embodiment of the present invention will be described in detail. In the figure, 1 is two points P and P spaced from the inner surface of the segment c (see FIGS. 4 and 6). Is a flat plate-shaped holder having an end portion 1a that can be abutted with, a reference numeral 2 is a magnet-type fixture having an electromagnet, and 2a is a side surface portion that can be attached by abutting the end surface of a steel segment c. 2a
and a magnet body 2b of the magnet-type fixture 2 arranged on the outer surface side of the holder 1 for magnetizing and demagnetizing the magnet body 2a arranged on the inner surface side of the holder 1. Is. The magnet type fixture 2 includes the magnet body 2a and the magnet switch 2b, and the side surface portion 2a of the magnet body 2a.
By closing the magnet switch 2b in the state where s is in contact with the end surface of the steel segment c, it can be attached to the same segment c. Reference numeral 3 is a non-contact type distance sensor such as an ultrasonic displacement sensor for measuring the tail clearance X, and 3a is a cable for transmitting a measurement signal output from the distance sensor 3. The distance sensor 3 is attached so as to be fitted into the holder 1, and is arranged so that the distance between the holder 1 and the inner surface of the tail plate b can be measured at the position where the end 1a of the holder 1 contacts the inner surface of the segment c. There is. In the distance sensor 3, since the flat plate-shaped holder 1 can contact the inner surface of the segment c at two points as described above, when the holder 1 contacts the inner surface of the segment c, The radial position is fixed and immovably positioned. Further, the distance sensor 3 is fixed so that the end portion on the measurement side thereof maintains a constant distance l ′ with respect to the holder 1,
Moreover, since the segment is a standard product and has a constant thickness, when the holder 1 is in contact with the inner surface of the segment c, the distance 1 from the end of the distance sensor 3 on the measurement side to the outer surface of the segment is equal to the holder 1 Is always constant regardless of which circumferential position on the inner surface of the segment abuts. Therefore, the distance sensor 3 can correctly measure the tail clearance X at any measurement point in the circumferential position of the segment. In this embodiment, the measurement signal output by the distance sensor 3 is transmitted by the cable 3a, but it may be transmitted wirelessly.

Reference numeral 4 denotes a spirit level mounted rotatably on an end surface 1b of the holder 1 opposite to the end 1a, 4a denotes an index indicating a reference position attached to the spirit level 4, and 4b denotes this index 4a. Correspondingly, it is an angle scale attached to the end surface portion 1b of the holder 1. The holder 1 is brought into contact with the inner surface of the segment c from the level 4 having the index 4a rotatably incorporated in the end surface 1b of the holder 1 and the angular scale 4b provided on the end surface 1b. An angle measuring means for measuring the circumferential position of the segment c at the time of performing is constructed and used in the operating method as shown in FIGS. 5 and 6. That is, as shown in these figures, when it is attempted to set the distance sensor 3 of the tail clearance measuring device at the circumferential position of the segment c at a desired angle θ, first, the level is rotated. Therefore, the index 4a is θ of the angle scale 4b.
Then, the holder 1 is fixed so as to point to a position corresponding to the position c, and then the holder 1 is brought into contact with the inner surface of the segment c and positioned so that the bubble of the spirit level comes to the center. Reference numeral 5 is an amplifier for amplifying the measurement signal output from the distance sensor 3 and transmitted through the cable, and reference numeral 6 is a display for displaying the tail clearance X calculated based on the amplified measurement signal by a numerical value. Since the tail clearance measuring device of the present embodiment can be made compact as it is configured separately from the shield body a portion and thus can be made compact, it can be configured to be portable like a tester.

Since the tail clearance measuring device of this embodiment has such a structure, when using this, first, the end 1a of the holder 1 is segmented into the segment c.
Of the magnet main body 2a of the magnet fixture 2 is brought into contact with the end face of the segment c while the contact state is maintained. By closing the switch 2b and magnetizing the magnet body 2a, the side surface 2
Attach as to the end face of segment c. In this state,
The distance sensor 3 is fixedly positioned with its radial and axial positions with respect to the segment c fixed. In this way, the measuring device of the present embodiment is set in the segment c, but when performing the setting, the level 4 and the holder 1
Positioning is performed so that the segment c can be set at a desired set position in the circumferential direction by using an angle measuring unit including the angle scale 4b of the end face portion 1b. When the measuring device is operated in the state set in this way, a measurement signal relating to the tail clearance is output from the distance sensor 3 and transmitted by the cable 3a, and the tail clearance is numerically displayed on the display unit 6. . The measuring device is set in the segment c, and the tail plate b moves as the shield machine excavates, so once the measuring device operates, thereafter, at each time during the excavation without any special operation. The tail clearance X of can be continuously measured. After excavating a unit length of underground mine with a shield machine, it is necessary to construct a new segment adjacent to the existing segment c, so it is necessary to remove the measuring device from the segment c, but at that time It can be easily removed by opening the magnet switch 2b and demagnetizing the magnet body 2a. After that, the operation described above may be repeated each time a new segment is constructed.

According to this embodiment, the end 1a of the holder 1 is
After contacting the inner surface of the segment c, the side surface portion 2as of the magnet main body 2a in the magnet mounting tool 2 is contacted with the end surface of the segment c and magnetically attached detachably, so that the tail clearance measuring device can be set. Unlike the conventional device and the improved conventional device, the segment c can be set at any position in the circumferential direction. In this case, the angle measuring means including the level 4 can be used to accurately position and set the segment at any desired position in the circumferential direction of the segment, so that the tail of the segment c at a desired setting position in the circumferential direction can be set. The clearance X can be measured. Moreover, the set of the tail clearance measuring device is,
Since it can be performed only by contacting the magnet attachment 2 and the magnet attachment 2 to the segment c, it can be easily performed even in a narrow working space in the shield body a.

According to the present embodiment, since the tail clearance measuring device is mounted so as to come into contact with the end surface of the segment c when it is set, the tail clearance measuring device is attached to a segment having a flange portion like the conventional device. There is nothing that can only be used. In addition, unlike the improved conventional device, it is not fixedly installed on the shield body a side via a jack for segment front end alignment, and is configured separately from the shield body a part and configured independently. Therefore, even if the shield machine rolls, the measurement result is not affected as in the improved conventional device, and the measurement error does not occur, and The mechanism is also extremely simple. Further, since the non-contact type sensor is used as the distance sensor 3, the tail plate may have a trouble in the operation of the distance sensor due to the sediment adhered to the inner surface of the tail plate as in the conventional device using the contact type distance sensor. b
It is not affected by the inner condition of the. According to the present embodiment, as described above, all the drawbacks of the conventional technique and the improved conventional technique can be overcome, and the segment can be accurately set at any position in the set segment circumferential direction, and the desired segment in the circumferential direction can be set. It is possible to obtain a tail clearance measuring device that can measure the tail clearance X at a set point and can easily set the tail clearance X.

In the present embodiment, the holder 1 is provided with the magnet fitting 2 so that, when the tail clearance measuring device is set, the fitting 2 is brought into contact with the end surface of the segment c and attached magnetically. Instead of such a magnet fixture 2, an abutting member having a suction means or a detachable adhesive means may be provided at a portion abutting on the end surface of the segment c. It suffices if a segment end face contact member that can be attached is provided. In this embodiment, the level measuring device 4 and the angle graduation 4b of the end surface 1b of the holder 1 are used as the angle measuring means. The angle measuring means uses the contact portion 1a of the holder 1 on the inner surface of the segment c. The type of the segment c is not limited as long as the position in the circumferential direction of the segment c can be measured. In the present embodiment, the measurement signal from the distance sensor 3 is displayed numerically on the display 6, but how to process the measurement signal is directly related to the object of the present invention. not,
It is a matter of design choice that can be appropriately selected when implementing the present invention.

[0016]

As is apparent from the above description, the present invention is directed to "a holder having an abutting portion capable of abutting at least two points on the inner surface of the segment, and an end surface of the segment provided on the holder. A non-contact type that is arranged so as to be able to measure the distance between the segment end face abutment member that abuts and can be removably attached, and the tail plate inner surface at the position where the abutting portion of the holder abuts the segment inner surface. The distance sensor and the angle measuring means for measuring the position in the circumferential direction of the segment when the abutting portion of the holder is brought into contact with the inner surface of the segment are provided "to configure the tail clearance measuring device. It can be set accurately at any position in the circumferential direction of the segment, and the tail clearance at the desired setting point in the circumferential direction can be measured, and It is possible to provide a tail clearance measuring device with a correspondence which can be performed in the set with ease. In addition to such a basic effect, the mechanism is extremely simple, but "it is not affected by the condition of the inner surface of the tail plate such as the adhesion of earth and sand like the conventional device", "Shield Even if the excavator rolls, it does not cause a measurement error like the improved conventional device, and it also has the effect of being able to achieve all the various drawbacks found in each conventional device. It can be resolved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a shield machine, showing a state in which a tail clearance measuring device according to an embodiment of the present invention is attached to an end of a segment, a part of which is a cross section.

FIG. 2 is an enlarged view of part A in FIG.

FIG. 3 is an arrow view of FIG. 2 viewed from a direction of an arrow A.

FIG. 4 is a view taken along the line BB of FIG.

5 is a view taken along the line CC of FIG.

FIG. 6 is an enlarged view of part A in FIG.

[Explanation of symbols] a Shield body b Tail plate c Segment X Tail clearance 1 Holder 2 Magnet fixture 2a Magnet body 2b Magnet switch 3 Distance sensor 4 Leveler 4a Level indicator 4b Angle scale 5 Amplifier 6 Indicator

Claims (1)

[Claims] 1. A tail clearance measuring device for measuring a tail clearance, which is a gap between an inner surface of a tail plate and an outer surface of a segment in a shield machine, which is capable of contacting at least two points with respect to the inner surface of the segment. Holder having such a contact portion, a segment end surface contact member which is provided on the holder and can be detachably mounted by contacting the end surface of the segment, and a tail at a position where the contact portion of the holder contacts the inner surface of the segment. A non-contact type distance sensor arranged so that the distance to the inner surface of the plate can be measured, and an angle measuring means for measuring the position in the segment circumferential direction when the contact portion of the holder is in contact with the inner surface of the segment. A tail clearance measuring device characterized by being provided with.