CN211348042U

CN211348042U - Tunnel boring machine hobbing cutter wearing and tearing on-line measuring device

Info

Publication number: CN211348042U
Application number: CN201921776671.1U
Authority: CN
Inventors: 张鑫; 刘建琴; 郭伟; 徐攀
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2019-10-22
Filing date: 2019-10-22
Publication date: 2020-08-25
Anticipated expiration: 2029-10-22

Abstract

The utility model relates to a tunnel boring machine hobbing cutter wearing and tearing on-line measuring device, including two kinds of sensors that are used for detecting the hobbing cutter sword circle, its characterized in that, the sensor be switch type hall sensor and magnetic sensing diode, set up the magnet steel in the different positions of the outer edge of hobbing cutter sword circle, make each magnet steel outwards the polarity the same, the magnet steel is along with the wearing and tearing of sword circle together; two magnetosensitive diodes which are arranged in an r area in an opposite way are selected to form a magnetosensitive diode differential circuit, a switch type Hall sensor outputs a digital signal after processing the output of a Hall element, and the magnetosensitive diode differential circuit outputs a measurement voltage value for judging whether a cutter is excessively worn; a sensor consisting of a switch type Hall sensor and a magnetic sensitive diode is fixed between the hob box and the cutter head rib plate. The utility model has the advantages of high measurement accuracy and uneasy damage.

Description

Tunnel boring machine hobbing cutter wearing and tearing on-line measuring device

Technical Field

The utility model relates to a tunnel boring machine, in particular to real-time detection method and device of hobbing cutter wearing and tearing.

Background

The tunnel boring machine has the advantages that the working environment is severe, the working condition is complex, the abrasion of the hob is serious, the stress state of a hob ring of the hob is continuously changed, the contact relation with a rock stratum is complex, the abrasion factors of the hob ring are numerous, the abrasion loss of the hob cannot be accurately calculated theoretically, and therefore the exact information of the abrasion of the hob can be obtained only through a detection mode. The existing detection of the abrasion condition of the hob is that a constructor enters the front section of a cutter head during the shutdown of the TBM, and measures the radius of a cutter ring by using a special measuring tape to judge the abrasion condition of the hob, so that the mode has low efficiency, large workload and time and labor waste; in addition, frequent shutdown not only delays the construction period, but also increases the risk of construction, and threatens the personal safety of operators. According to statistics, the time for detecting the abrasion of the cutter and replacing the cutter occupies 30-40% of the working time of the tunnel boring machine. Therefore, in order to improve the working efficiency of the tunnel boring machine and reduce the downtime, the abrasion condition of the hob at each position on the cutter head needs to be monitored on line so as to replace the excessively abraded hob.

SUMMERY OF THE UTILITY MODEL

To prior art, the utility model provides an on-line monitoring device of hobbing cutter wearing and tearing and hobbing cutter rotational speed improves tunnel boring machine work efficiency, reduces down time, reduces engineering cost. The technical scheme is as follows:

an online detection device for abrasion of a hob of a tunnel boring machine comprises two sensors for detecting a hob ring, and is characterized in that the sensors are a switch type Hall sensor and a magnetic sensitive diode, magnetic steels are arranged at different positions of the outer edge of the hob ring, so that the outward polarities of the magnetic steels are the same, and the magnetic steels are abraded along with abrasion of the hob ring;

selecting two magnetosensitive diodes which are arranged in an r area in an opposite way to form a magnetosensitive diode differential circuit, utilizing a switch type Hall sensor to work with the magnetosensitive diode circuit, processing the output of a Hall element by the switch type Hall sensor and then outputting a digital signal, setting a starting threshold value, when magnetic steel rotates to the position right opposite to the magnetosensitive diode and the switch type Hall sensor along with a hob, the Hall element detects that the magnetic field intensity is maximum, the switch type Hall sensor outputs a high level, recording the measuring voltage value of the magnetosensitive diode differential circuit at the moment, rotating the hob for one circle and corresponding to the magnetic steel at different positions, and respectively obtaining a measuring voltage value for judging whether a cutter is excessively worn;

a sensor consisting of a switch type Hall sensor and a magnetic sensitive diode is fixed between the hob box and the cutter head rib plate.

Preferably, a wear-resistant baffle plate 1, a heat-insulating gasket 15 and a rubber protection ring 9 are arranged between the sensor and the hob ring; the wear-resistant baffle 1 is fixed on the knife box to isolate the external environment from the sensor, and a seal ring 3 is adopted to seal the gap of the wear-resistant baffle 1; the heat insulation gasket 15 is used for reducing the influence of temperature on the sensor, and the rubber protection ring 9 plays a role in buffering and protecting the sensor; the knife box and the knife ring are connected through an outer sleeve 7; the switch type Hall sensor 4 and the magnetic sensitive diode sensor 14 are fixed in the sensor protective shell 10 through a rubber protection ring 9, and the sensor protective shell 10 is sealed through a waterproof sealing ring 12; the base 8 is fixedly connected to the cutter head rib plate 6, and the sensor protection shell is fixedly connected with the base 8, so that the installation, fixation and protection of the sensor are realized.

The advantages of measuring the wear of the hob by adopting the device are as follows:

the Hall sensor and the magnetic sensitive diode utilize Hall effect and belong to magnetic sensitive sensors. By adopting non-contact measurement, the switch type Hall sensor is integrated, has firm structure, small volume, light weight, long service life, convenient installation, small power consumption, high frequency, vibration resistance, no fear of pollution or corrosion of dust, oil stain, water vapor and the like, and is suitable for the severe working environment of the shield machine. The magnetic sensitive diode is a magnetic sensitive sensor, has high sensitivity of detecting magnetic field change, is hundreds times to thousands times of the sensitivity of the Hall element, is suitable for detecting weak magnetic field change, and has small volume and low power consumption. The on-line monitoring of the abrasion of the cutter of the tunnel boring machine can be realized, the working efficiency of the tunnel boring machine is improved, the downtime is reduced, the construction period is shortened, the artificial workload is reduced, and the construction cost is reduced.

Drawings

FIG. 1 is a schematic diagram of arrangement of magnetic steel on a hob

FIG. 2 is a differential circuit diagram of a magnetic sensing diode

FIG. 3 is a schematic diagram of a magnetic sensing diode measurement circuit

FIG. 4 is an overall view of sensor installation

FIG. 5 is a front cut-away view of a sensor mounting

FIG. 6 is a partial enlarged view of a sensor mounting portion of FIG. 5

In the figure:

1-wear-resistant baffle, 2-screw, 3-sealing ring, 4-switch type Hall sensor, 5-side panel of knife box, 6-knife disc rib plate, 7-outer sleeve, 8-sensor base, 9-rubber protection ring, 10-sensor protection shell, 11-data transmission cable, 12-lead hole waterproof sealing ring, 13-bolt, 14-magnetic sensitive diode differential circuit sensor, 15-heat insulation gasket, 16-magnetic steel, 17-hob ring, 18-hob fixing block, 19-knife rest, 20-hob retaining ring, 21-hob body

Detailed Description

The present invention will be further described with reference to the following drawings and specific examples, but the following examples are by no means limiting the present invention.

To the prior art, the utility model provides an online monitoring method and device of hobbing cutter wearing and tearing and hobbing cutter rotational speed. The utility model adopts two magnetosensitive diodes to form a differential circuit, and a switch type Hall sensor to work cooperatively, and the differential circuit is arranged in a cutter box to monitor the hob ring on line in real time,

as shown in fig. 1, four magnetic steels are uniformly distributed on the hob ring 17 at 90 ° to make the N pole of the magnetic steel face the outside of the hob ring; the magnetic steel can be worn along with the abrasion of the cutter ring.

To adapt toThe shield machine works at high temperature, and silicon magnetic sensing diodes with good temperature characteristics are selected to form a differential circuit. As shown in fig. 2 and 3. Two magnetosensitive diodes and two resistors R arranged oppositely in R region (high recombination region) are selected_LThe differential circuit is composed of external power supply and voltmeter, and under the action of magnetic steel magnetic field, the I region (intrinsic region) current of two magnetosensitive diodes is changed in opposite direction, and its resistance value is changed in opposite direction. When the magnetic steel in the hob is not abraded, the magnetic field passing through the magnetosensitive diode is maximum, and then the magnetosensitive diode D₁Under the action of the magnetic field generated by the magnetic steel, the electrons and the holes deflect to the r surface, so that the current passing through the I area is minimum, and the resistance of the I area is maximum. In the magnetic sensitive diode D₂The current is maximum in the middle I region. Then along with the abrasion of the hob, the magnetic steel is also abraded, so that the distance from the magnetic steel to the magnetic sensitive diode is continuously reduced, and the magnetic sensitive diode D passes through₁、D₂Magnetic field reduction of D₁The electrons and holes in the middle deflection r surface are continuously reduced, the current in the I area is continuously increased, the resistance is continuously reduced, and D₂The resistance constantly increases in, and the voltmeter number of degrees constantly reduces, can measure the relation between hobbing cutter sword circle wearing and tearing volume and the voltmeter number of degrees through the experiment, and the degree of reaction hobbing cutter wearing and tearing, measuring voltage is less, and hobbing cutter sword circle wearing and tearing are more serious more, and the sword circle radius is less, detects the wearing and tearing condition of four positions departments of hobbing cutter sword circle through the record, and the holistic wearing and tearing condition of reaction hobbing cutter judges whether need to change the cutter.

In order to reduce the mutual interference of other magnetic fields and the magnetic fields generated by 4 pieces of magnetic steel distributed on a cutter ring and enable the data extraction and detection to be clearer, a switch type Hall sensor integrating circuits such as a Hall element, a voltage stabilizing circuit, an amplifier, a Schmidt trigger, an oc (collector open-circuit output gate) and the like is matched with a magnetic sensitive diode circuit to work, and the switch type Hall sensor can output a high-level or low-level digital signal after the output of the Hall element is processed. Setting a starting threshold value, when the magnetic steel rotates to a position opposite to the magnetic sensitive diode and the switch type Hall sensor along with the hob, the Hall element measures the magnetic field intensity to be the maximum, the switch type Hall sensor outputs a high level, and then the circuit voltage U of the magnetic sensitive diode is recorded₀Reading, measuring when the hob is rotated for one turnFour voltage values are measured, and when the voltage is lower than a set value, the cutter is proved to be excessively worn and needs to be replaced.

In addition, the time interval between the high levels of each switch type Hall sensor is calculated, so that the rotating speed of the hob can be indirectly obtained, and the pure rolling distance of the hob can be obtained through calculation. And whether the hob is blocked, eccentrically worn and the like can be detected. When the switch type hall sensor does not output for a long time or always outputs a high level, the hob may be blocked and needs to be replaced and maintained.

As shown in fig. 4 and 5, the utility model provides an online monitoring device for hob abrasion, which installs a sensor composed of a switch type hall sensor and a magnetosensitive diode differential circuit between a hob box and a hob disk rib plate. And magnetic steel is arranged in the hob.

The specific installation method is shown in fig. 6, and a wear-resistant baffle plate 1, a heat-insulating gasket 15 and a rubber protection ring 9 are arranged between the sensor and the hob ring. Wherein wear-resisting baffle 1 passes through screw 2 to be installed on the knife case, is made by POM plastics, has high rigidity, high wearability, and is isolated with external environment and sensor to avoid around the influence of metal to two magnetic sensors, can dismantle the change. Adopt sealing washer 3 to seal the antifriction plate space, prevent that dust, greasy dirt from getting into. The heat insulation gasket 15 is used for reducing the influence of temperature on the sensor, and the rubber protection ring 9 plays a role in buffering and protecting the sensor. The outer sleeve 7 is connected with the cutter box and the cutter head to form a sensor mounting channel. The switch type Hall sensor 4 and the magnetic sensitive diode sensor 14 are adhered to the rubber protection ring 9 through glue, are installed in the sensor protection shell 10, are sealed by injecting waterproof sealant into the cavity of the protection shell and play a role in cushioning protection, the data transmission line is connected with an external data acquisition device through a lead hole, and the protection shell is sealed through a waterproof sealing ring 12. The base 8 is fixed on the cutterhead rib plate 6 through a bolt 13, blocks the sensor shell, and fixedly locks the sensor shell, so that the installation, fixation and protection of the two sensors are realized.

Claims

1. An online detection device for abrasion of a hob of a tunnel boring machine comprises two sensors for detecting a hob ring, and is characterized in that the sensors are a switch type Hall sensor and a magnetic sensitive diode, magnetic steels are arranged at different positions of the outer edge of the hob ring, so that the outward polarities of the magnetic steels are the same, and the magnetic steels are abraded along with abrasion of the hob ring;

two magnetosensitive diodes which are arranged in an r area in an opposite way are selected to form a magnetosensitive diode differential circuit, a switch type Hall sensor outputs a digital signal after processing the output of a Hall element, and the magnetosensitive diode differential circuit outputs a measurement voltage value for judging whether a cutter is excessively worn;

2. The device according to claim 1, characterized in that a wear-resistant shield (1), a heat-insulating spacer (15) and a rubber protective ring (9) are arranged between the sensor and the hob ring; the wear-resistant baffle (1) is fixed on the knife box, the external environment is isolated from the sensor, and a seal ring (3) is adopted to seal the gap of the wear-resistant baffle (1); the heat insulation gasket (15) is used for reducing the influence of temperature on the sensor, and the rubber protection ring (9) plays a role in buffering and protecting the sensor; the knife box and the knife ring are connected through an outer sleeve (7); the switch type Hall sensor (4) and the magnetic sensitive diode sensor (14) are fixed in the sensor protective shell (10) through a rubber protection ring (9), and the sensor protective shell (10) is sealed through a waterproof sealing ring (12); the base (8) is fixedly connected to the cutter head rib plate (6), and the sensor protection shell is fixedly connected with the base (8), so that the installation, fixation and protection of the sensor are realized.