Shield tunneling machine scraper position detection system

Abstract

The invention discloses a shield tunneling machine scraper position detection system, which comprises a tool apron, a force transducer and a scraper, and is characterized in that the tool apron is provided with a tool apron bolt hole; the tool apron is further provided with at least one sensor mounting hole. The force measuring sensor is mounted in a sensor mounting hole of the tool apron; the force measuring sensor comprises a sensor body, an inductive head and a control line. The inductive head of the force measuring sensor protrudes out of the side face, connected with the scraper, of the scraper holder. The scraper comprises a scraper bolt hole, and the scraper is fixed on the tool apron through a bolt. The loosening condition of the scraper in the using process is monitored through the force measuring sensor installed on the scraper holder, an alarm is given according to the pressure grade when the loosening condition reaches the lowest pressure grade, the system transmits prompt information to a touch screen of a shield operation room through PLC operation, shield operation personnel are informed in time, the operation personnel take corresponding measures, and the operation efficiency is improved. A series of unnecessary losses caused by loosening or falling of the cutter are reduced, the construction progress is accelerated, and the construction benefits are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of shield construction equipment, and in particular relates to a shield machine scraper position detection system. Background Art

[0002] The shield machine is an important equipment for tunneling, in which the scraper on the cutterhead plays a vital role in the cutting and excavation process. The scraper is not only used for cutting soft soil layers, but also for cutting soil and non-hard rock layers in composite layers after being crushed by the roller cutter. Therefore, the working state of the scraper has a direct impact on the excavation efficiency and construction quality of the shield machine.

[0003] In the actual construction process, the shield machine scraper may become loose or fall off, which will cause the cutterhead cutting track to deviate, the excavation diameter does not meet the requirements, and increase the workload of other cutters, further accelerating the wear of the cutters. If this situation is not discovered and handled in time, it will not only reduce construction efficiency, but also may cause significant economic losses.

[0004] In order to solve the above problems, a variety of technical solutions have been proposed, such as a monitoring method for judging the wear of the tool based on the color of the slag, and a system for online real-time monitoring of scraper wear. However, these solutions mostly focus on monitoring the wear of the tool, but fail to effectively solve the problem of tool loosening and falling off. In addition, the scraper installation methods in the prior art (such as bolt connection and plug-in installation) are prone to loosening during long-term use, which in turn affects construction. Summary of the invention

[0005] The purpose of the invention is to provide a shield machine scraper position detection system.

[0006] The technical solution of the present invention for solving the above-mentioned technical problems is as follows: a shield machine scraper position detection system, comprising: a tool holder, a force sensor and a scraper, the tool holder is provided with a tool holder bolt hole; the tool holder is also provided with at least one sensor mounting hole; the force sensor is installed in the sensor mounting hole of the tool holder; the force sensor comprises a sensor body, a sensing head and a control line, the sensing head is installed on the sensor body, and the control line is used to transmit the signal generated by the sensing head; the sensing head of the force sensor protrudes from the side where the tool holder and the scraper are connected; the scraper comprises a scraper bolt hole, and the scraper is fixed to the tool holder by bolts so that the scraper contacts the force sensor.

[0007] The shield machine scraper position detection system of the present invention as described above, further, the number of the sensor mounting holes is two, the sensor mounting holes are respectively arranged at a first position where the blade holder is closer to the cutting surface and a second position where the blade holder is farther from the cutting surface, and the number of the force sensors is two.

[0008] The shield machine scraper position detection system of the present invention as described above, further, the rated range of the force sensor is 5MPa~10MPa; the working stable temperature range is -10℃~70℃.

[0009] The shield machine scraper position detection system as described above in the present invention further includes a transfer PCL integrated box, an integrated box power supply circuit, a main control box and a display, wherein the transfer PCL integrated box is connected to the control line of the force sensor via a pre-buried line, the transfer PCL integrated box is connected to the integrated box power supply circuit, the transfer PCL integrated box communicates with the main control box wirelessly, and the main control box is connected to the display via a display connection line.

[0010] The shield machine scraper position detection system of the present invention as described above, further, the pre-buried line is pre-buried in the cutterhead spoke beam of the shield machine; the flange surface of the shield machine cutterhead and the rotation center are provided with through holes, the pre-buried line enters the central rotating body from the through holes and is connected to the transfer PCL integrated box arranged in the central rotating body.

[0011] The shield machine scraper position detection system of the present invention as described above, further, the force sensor is fixed in the sensor installation hole by means of shockproof material.

[0012] The shield machine scraper position detection system of the present invention as described above, further, the display is configured with a touch screen interface, through which the state of the scraper is monitored in real time, and the display parameters can be adjusted or the alarm threshold can be set.

[0013] The shield machine scraper position detection system of the present invention as described above further has a data cache module arranged in the transfer PCL integrated box, which temporarily stores data when wireless communication is interrupted and automatically transmits the data to the main control box after communication is restored.

[0014] The beneficial effects of the present invention are: The shield machine scraper position detection system is used to monitor the high-frequency vibration generated by the scraper when the cutterhead rotates and cuts soil and soft rock, and judge whether the scraper cuts the soil normally and whether the cutter body loosens or falls off during the cutting process. The two sets of force sensors installed on the scraper seat monitor the tight connection between the scraper and the scraper seat. If the scraper locking pressure is found to be lower than the first set threshold (such as 89.09bar), it can be judged that the scraper has signs of loosening. If the static locking pressure of the scraper is lower than the second set threshold (the second set threshold is less than the first set threshold, such as 60bar), it can be judged that the scraper has loosened and needs to be tightened; if the pressure of the scraper is stable and has no fluctuations in the dynamic movement, it can be judged that the scraper is severely worn or broken. According to the above, the staff can judge a situation of the scraper at work based on this information, so as to make corresponding adjustments and measures in time to avoid severe wear or falling of the scraper, resulting in insufficient excavation diameter or wear of the cutterhead, which will bring delays and unnecessary economic losses to the construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and / or other advantages of the present invention will become clearer and easier to understand through the detailed description made in conjunction with the following drawings, which are only exemplary and do not limit the present invention, wherein: Figure 1 A schematic diagram of a knife seat according to an embodiment of the present invention; Figure 2 A schematic diagram of a force sensor according to an embodiment of the present invention; Figure 3 A schematic diagram of the installation combination of a scraper and a blade holder according to an embodiment of the present invention; Figure 4 A schematic diagram of a scraper working state according to an embodiment of the present invention; Figure 5 A schematic diagram of a shield machine scraper position detection system according to an embodiment of the present invention.

[0016] In the accompanying drawings, the components represented by the reference numerals are listed as follows: 1. Tool holder, 11. Tool holder bolt hole, 2. Force sensor, 21. Sensor body, 22. Sensing head, 23. Control line, 3. Scraper, 31. Scraper bolt hole, 32. Alloy head, 4. Soft rock, 41. Cutting surface, 5. Embedded line, 6. Transfer PCL integrated box, 7. Integrated box power supply line, 8. Main control box, 9. Display, 91. Display connecting line. DETAILED DESCRIPTION

[0017] Hereinafter, embodiments of a shield machine blade position detection system of the present invention will be described with reference to the accompanying drawings.

[0018] The embodiments described herein are specific embodiments of the present invention, which are used to illustrate the concept of the present invention, are illustrative and exemplary, and should not be construed as limiting the embodiments of the present invention and the scope of the present invention. In addition to the embodiments described herein, those skilled in the art can also adopt other obvious technical solutions based on the claims and the contents disclosed in the specification of this application, including technical solutions that adopt any obvious replacement and modification of the embodiments described herein.

[0019] The drawings of this specification are schematic diagrams, which assist in explaining the concept of the present invention and schematically show the shapes of various parts and their mutual relationships. Please note that in order to clearly show the structures of various components of the embodiments of the present invention, the drawings are not drawn according to the same scale. The same reference numerals are used to represent the same parts.

[0020] The shield machine cutter is selected according to the geological conditions and the movement mode, layout position, shape, etc. of the cutter. According to the cutting principle, the cutters of the shield machine are generally divided into two types: cutting cutters and hobs. Other forms of cutters are generally auxiliary cutters. Among them, the cutting cutters are divided into: scrapers, tooth cutters, pre-cutters, fishtail cutters, etc. Here is a brief explanation of the types of scrapers. The scraper installation methods are divided into bolt type, insert type and welding type. At present, the shield machine commonly uses bolt type and insert type to install scrapers, and the welding type is gradually eliminated. Although the welding type is more reliable, it is not conducive to the rapid replacement of worn or damaged scrapers. Although the bolt-connected and inserted scrapers are easy to disassemble, they are prone to problems such as loose bolts and loose pin ends during long-term use. Once the scraper is loose, it will accelerate the wear or damage of the scraper. In order to monitor whether the bolts are loose, whether the pin ends are loose, and whether the scraper and the blade seat are tightly connected during use, in order to monitor whether the scraper is loose during use, whether the bolts are loose, whether the pin ends are loose, and whether the scraper is tightly connected to the blade seat.

[0021] refer to Figures 1 to 5 A shield machine scraper position detection system according to an embodiment of the present invention is described, which mainly includes a scraper holder 1 , a force sensor 2 and a scraper 3 .

[0022] The blade seat 1 is provided with a blade seat bolt hole 11 for mounting the scraper 3 , and at least one sensor mounting hole for mounting the force sensor 2 .

[0023] The tool holder is lathe-machined, and the position for installing the force sensor is turned out. The force sensor line is taken out from the inside of the tool holder through the pre-buried hole. According to the design drawing of the cutter head, the bolts used for the 8-hole scraper tool holder are M24*70mm hexagon socket bolts, with a strength grade of 10.9 and a bolt tightening torque of 890Nm. It is known that the torque unit can be converted to KGm through the formula, and the formula 1Nm=0.102KG.m: 890NM=90.82KGM. It is known that the conversion relationship between KGM (kilogram force / square centimeter) and bar can be expressed by a mathematical formula: 1KGM=0.981bar, 90.82KGM*0.981bar=89.09bar. From the above formula, we can know that after locking the scraper, the sensor pressure display value is ≥89.09bar, which means that the scraper has been tightened in place. Subsequently, the looseness of the scraper can be judged by the scraper seat force sensor display value displayed on the touch screen of the operating room. Based on this information, the excavation data and tool changing work can be adjusted in time.

[0024] The force sensor 2 is fixed on the knife holder 1 through the mounting hole. The force sensor 2 includes a sensor body 21, a sensor head 22 and a control line 23. The sensor head 22 contacts the surface of the knife holder 1 through the sensor body 21, and the sensor head 22 protrudes from the side where the knife holder 1 is connected to the scraper 3, and is used to detect the fastening state of the scraper 3 during operation. The force sensor is designed based on the force principle of elastic elements, and the resistance value changes through the deformation of the force, which is then converted into an electrical signal output by the force measuring circuit, thereby realizing the measurement of force. The load cell has an outer diameter of 8.5mm, a height of 5mm, a rated range (RC) of 5-10MPa, a full-scale output (RO) of 0.5-1.2mV / V, a maximum excitation voltage of 12V, nonlinearity of ±1.0%RO, hysteresis of ±1.0%RO, creep (30 minutes) of ±0.5%RO, zero-point output of ±2% of RO, impedance of 350Ω±5%, temperature compensation range of 0-50℃, working stability range of -10~70℃, insulation resistance of 5000MΩ, input impedance of 700±10Ω, output impedance of 700±5%, lead cable size of φ1.6*4Core*3m, safe overload of 120%RC, and a material of stainless steel. Due to the harsh construction area of ​​the cutter head, it is difficult to install and use general sensors, and the force sensor is suitable for the anti-loosening function of the cutter head scraper due to its small size, high precision, and good stability.

[0025] The scraper 3 is connected to the blade holder 1 by bolts, and the bolt hole 31 of the scraper 3 is aligned with the bolt hole 11 of the blade holder 1, so that the scraper 3 keeps in contact with the force sensor 2. The force sensor 2 can sense the pressure changes between the scraper 3 and the blade holder 1 in real time, and transmit the signal to the remote device for analysis through the control line 23. Weld the scraper holder with force sensor to the specified position of the cutter disc, and then install the scraper, and use M24, strength grade ≥10.9 hexagon socket bolts to tighten and lock it. The tightening condition is judged by the pressure fed back by the force sensor. The scraper can be used only after the tightening force of all scrapers is ≥89.09bar.

[0026] In specific implementation, the system of the present invention is provided with two sensor installation holes, which are respectively located at a first position where the blade holder 1 is close to the cutting surface 41 and a second position where the blade holder 1 is far from the cutting surface 41, and a force sensor 2 is installed at each position to monitor the force conditions of the scraper 3 at different positions. The rated range of each force sensor 2 is 5MPa to 10MPa, and it can maintain stable operation within the operating temperature range of -10℃ to 70℃, thereby ensuring that the system can accurately detect the tightening state of the scraper 3 under various complex working conditions.

[0027] To achieve remote monitoring and data transmission, the present invention also includes a transfer PCL integrated box 6, an integrated box power supply line 7, a main control box 8 and a display 9. The force sensor 2 is connected to the transfer PCL integrated box 6 through the pre-buried line 5, the transfer PCL integrated box 6 is connected to the integrated box power supply line 7, and the integrated box 6 and the main control box 8 are connected through wireless communication for data transmission. The display 9 is connected to the main control box 8 through a display connection line 91, and is used to display the force state of the scraper 3 in real time.

[0028] In the cutterhead structure of the shield machine, the embedded line 5 is arranged along the spoke beam of the cutterhead, and enters the central rotating body through the through hole of the flange surface of the shield machine cutterhead, and finally connects to the transfer PCL integrated box 6. This wiring method can effectively avoid the entanglement and damage of the cable when the cutterhead rotates, thereby ensuring the long-term stable operation of the system. The transfer PCL integrated box transmits the signal to the main control box through wireless signal transmission, thereby reducing the wiring pressure of the central rotating body, and the wireless transmission is not easily affected by external electromagnetic interference, with low comprehensive cost and stable performance, eliminating the cost of wiring and cable maintenance.

[0029] In order to improve the stability of the force sensor 2, the sensor 2 is fixed in the sensor mounting hole of the tool holder 1 by means of shockproof material to prevent the high-frequency vibration during the operation of the shield machine from affecting the measurement accuracy.

[0030] The display 9 is equipped with a touch screen interface, and the operator can monitor the working status of the scraper 3 in real time through the touch screen, and can adjust the display parameters or set the alarm threshold as needed, so as to detect abnormal situations in time and take corresponding measures to ensure construction safety.

[0031] In addition, a data cache module is provided in the transfer PCL integrated box 6 of the present invention. When wireless communication is interrupted, the data cache module can temporarily store the data collected by the force sensor 2. After the communication is restored, the system will automatically transmit the stored data to the main control box 8 to ensure the integrity of the data.

[0032] Combination Figure 5 The operation process of the scraper position detection system of the shield machine of the present invention is described: when the scraper cuts and guides soft rock or soft soil through the cutter disc, high-frequency vibration will be generated. Long-term high-frequency vibration is a factor that induces the loosening of the fastening bolts and produces metal fatigue. Therefore, we install 2 sets of force sensors on the scraper seat to monitor the tightening condition of the scraper bolts. The initial tightening pressure of the force sensor is ≥89.09bar, and the nearest point of the scraper alloy head and the farthest point of the scraper alloy head are monitored respectively. Under normal circumstances, the loosening or falling off of the scraper during operation starts from the cutting soil end, that is, the scraper alloy head end. At this time, the force sensor will promptly display the loosening pressure value at the scraper alloy head. After the loosening pressure value reaches 60bar, the display system will prompt that the pressure display of the force sensor is abnormal. If the loosening value of the force sensor continues to decrease, causing the pressure of another force sensor of the force sensor to be lower than 60bar, the system will transmit it to the operator through the touch screen in the form of a warning. At this time, the operator can make corresponding measures and adjustments according to the alarm information and the corresponding cutter disc scraper number.

[0033] The technical features disclosed above are not limited to the disclosed combinations with other features. Those skilled in the art may also make other combinations between the technical features according to the purpose of the invention to achieve the purpose of the invention.

Claims

1. A shield machine scraper position detection system, characterized in that: include: A knife seat (1), a force sensor (2) and a scraper (3), wherein the knife seat (1) is provided with a knife seat bolt hole (11); the knife seat (1) is also provided with at least one sensor mounting hole; the force sensor (2) is mounted in the sensor mounting hole of the knife seat (1); the force sensor (2) comprises a sensor body (21), a sensing head (22) and a control line (23); the sensing head (22) is mounted on the sensor body (21), and the control line (23) is used to transmit the signal generated by the sensing head (22); the sensing head (22) of the force sensor (2) protrudes from the side of the knife seat (1) where the scraper (3) is connected; the scraper (3) comprises a scraper bolt hole (31), and the scraper (3) is fixed to the knife seat (1) by bolts so that the scraper (3) contacts the force sensor (2).

2. The shield machine scraper position detection system according to claim 1 is characterized in that the number of the sensor mounting holes is two, and the sensor mounting holes are respectively arranged at a first position where the tool holder (1) is closer to the cutting surface (41) and a second position where the tool holder (1) is farther from the cutting surface (41), and the number of the force sensors (2) is two.

3. The shield machine scraper position detection system according to claim 1, characterized in that: The rated range of the force sensor (2) is 5MPa to 10MPa; the stable working temperature range is -10°C to 70°C.

4. The shield machine scraper position detection system according to claim 1, characterized in that: The invention also comprises a transfer PCL integrated box (6), an integrated box power supply circuit (7), a main control box (8) and a display (9); the transfer PCL integrated box (6) is connected to a control line (23) of the force sensor (2) via a pre-buried circuit (5); the transfer PCL integrated box (6) is connected to the integrated box power supply circuit (7); the transfer PCL integrated box (6) communicates with the main control box (8) via wireless; and the main control box (8) is connected to the display (9) via a display connection line (91).

5. The shield machine scraper position detection system according to claim 4, characterized in that: The pre-buried line (5) is pre-buried in the spoke beam of the cutterhead of the shield machine; through holes are provided on the flange surface and the rotation center of the cutterhead of the shield machine, and the pre-buried line (5) enters the central rotating body from the through holes and is connected to the transfer PCL integrated box (6) arranged in the central rotating body.

6. The shield machine scraper position detection system according to claim 1, characterized in that: The force sensor (2) is fixed in the sensor installation hole by means of a shockproof material.

7. The shield machine scraper position detection system according to claim 1, characterized in that: The display (9) is provided with a touch screen interface, through which the state of the scraper (3) is monitored in real time, and display parameters can be adjusted or alarm thresholds can be set.

8. The shield machine scraper position detection system according to claim 1, characterized in that: A data cache module is arranged in the transfer PCL integrated box (6). The data cache module temporarily stores data when wireless communication is interrupted, and automatically transmits the data to the main control box (8) after communication is restored.

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