JPH0345198B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention prevents dirt from entering the shield body through the gap between the outer circumference or inner circumference of a rotatable cutter wheel and the shield body. The present invention relates to a wear detection device for a cutter seal of a shield excavator, in which a plurality of rows of cutter seals for preventing cutter seals are arranged at intervals.

[Background of the invention]

In recent years, there has been a growing demand for shield tunneling machines with diameters as large as 10 m, and the cutter wheels and their drive devices have also become larger accordingly. The bearing that supports the cutter wheel is a rolling bearing, which is necessary to increase drive efficiency, has a large diameter that matches the diameter of the cutter wheel, and has a special structure due to the load conditions. Furthermore, this bearing is required to rotatably support the cutter wheel until the planned route is excavated, and failure is not an option. Therefore, in the event of a failure, it would be extremely difficult to manufacture a replacement bearing, as well as carry in and assemble the bearing, and the negative impact on excavation work would be immeasurable. It is necessary to provide adequate protection. In addition to this bearing, the cutter wheel's drive device includes a drive gear, and like bearings, if a failure occurs, it will be a serious situation and must be adequately protected. However, the reality is that conventional shield tunneling machines have not been sufficiently protected. A general example of protection for a conventional cutter wheel drive device will be explained with reference to FIG. Reference numeral 1 denotes a shield main body, the front part of which is composed of a hood part 1a, a partition wall 1b, etc. Reference numeral 2 denotes a cutter wheel for excavating the earth, which is rotatably supported on the partition wall 1b via a bearing 3. 4 is a motor for driving the cutter wheel 2, which is attached to the partition wall 1b. A pinion 5 is fixed to the shaft end of the drive motor 4 and meshes with a gear 6 fixed to the cutter wheel 2. In the gap between the outer periphery of the cutter foil 2 and the inner periphery of the hood part 1a, multiple rows of cutter seals 7 are arranged at appropriate intervals to prevent dirt and muddy water from entering the shield body 1. In addition, in the gap between the inner circumference of the cutter foil 2 and the partition wall 1b, there are multiple rows of cutter seals 8 for preventing dirt and muddy water from entering the shield body 1 from the chamber 11.
are arranged at appropriate intervals. The cutter seals 7 and 8 have a plurality of parallel lips and are fixed to the cutter foil 2. 9 is a space formed before and after the cutter seal 7, and 10 is a space formed before and after the cutter seal 8.

The shield excavator excavates by rotating the cutter wheel 2, but although the cutter wheel 2 is supported by the bearing 3, the cutting resistance of the face and its own weight are compounded by manufacturing errors, so the rotational state of the cutter wheel 2 is The rotation will not be in a perfect circle, but will be slightly eccentric. For this reason, the sliding surface pressure of the sliding surfaces of the cutter seals 7 and 8 irregularly occurs in some parts where it is high and in some parts where it is low. Frictional heat is generated in sliding parts with high surface pressure, whereas frictional heat is not a problem in sliding parts with low surface pressure, but the lack of surface pressure makes it easy for dirt and mud to enter. Since the cutter wheel 2 is continuously rotated, if a small amount of dirt enters the sliding surface, it will immediately reach the sliding portion where the surface pressure is high, and generate frictional heat as well as the cutter seals 7 and 8.
This promotes wear on the sliding surfaces of the shield body 1 and the lips of the shield body 1. As this wear accelerates, the amount of dirt and mud that enters gradually increases, further accelerating the wear, and eventually enters the meshing surfaces of the bearing 3, pinion 5, and gear 6, causing the cutter wheel 2 to become unable to drive. A serious situation occurs.

Conventionally, as a countermeasure against this problem, spaces 9 and 10 were formed in the lips of the cutter seals 7 and 8 and at the front and rear sides.
It is filled with grease at a constant pressure higher than the mud water pressure of the invading ground. The grease is almost the same as the grease supplied to the bearing 3, and the space 9,
Judging from the rotational resistance of the drive motor 4 and changes in the rotational sound of the cutter wheel 2, grease flows into the earth and sand from a grease supply port (not shown) arranged to supply grease toward the motor 10. Operators are supplying water as needed to compensate for the amount consumed.
In this way, conventional cutter wheel drive devices are protected by simply filling the lip of the cutter seal and the space before and after the cutter seal with grease at a pressure higher than the mud water pressure of the ground, and replenishing the grease is mostly done by the operator. Since it is based on intuition, it is inevitable to replenish excess grease, and it is not possible to accurately judge the wear status of the cutter seal and mating sliding surface, so sufficient protection cannot be expected. Ta.

[Purpose of the invention]

The present invention solves the above-mentioned problems and prevents the occurrence of a serious situation in which the cutter wheel cannot be driven, and also extends the life of the cutter seal.
Another object of the present invention is to provide a cutter seal wear detection device that can prevent wasteful consumption of grease by properly replenishing grease.

[Summary of the invention]

In the cutter seal wear detection device for a shield excavator according to the present invention, a plurality of rows of cutter seals for preventing the intrusion of earth and sand into the shield body are arranged around a peripheral portion of a cutter wheel rotatably attached to the shield body, and a plurality of rows of cutter seals for preventing the intrusion of earth and sand into the shield body. In the shield excavator, a temperature sensor for measuring the temperature of the seal sliding surface of the shield body is provided on the shield body at a position facing each of the cutter seals, and a temperature sensor is provided on the shield body at a position facing each of the cutter seals. A pressure sensor is provided on the shield body at a position facing the space formed before and after each cutter seal to measure the pressure of the grease sealed in the space.

[Embodiments of the invention]

An embodiment of the present invention will be explained with reference to FIG. In the figures, the same reference numerals as in FIG. 3 indicate the same elements or the same functions. 12 are all thermocouple type temperature sensors, and the temperature sensor 12 is connected to a plurality of rows of cutter seals 7 arranged at intervals in a gap between the outer circumference of the cutter foil 2 and the inner circumference of the hood part 1a. , are embedded in the hood portion 1a at opposing positions. and temperature sensor 1
2, the number provided on the circumference is increased or decreased depending on the diameter of the shield tunneling machine. In order to detect the temperature at each part on the circumference, it is better to provide a large number of temperature sensors, but if the diameter is small and the amount of deformation of the cutter foil 2 is small, the number of temperature sensors 12 to be provided is one on the circumference.
One piece is enough. The tip of the temperature sensor 12 is mounted close to the sliding surface in consideration of the amount of wear on the sliding surface so that temperature changes on the sliding surface can be detected as sensitively as possible. Grease is filled in the space 9 between each lip of each cutter seal 7 and in the front and back, as in the conventional case, at a pressure higher than the mud water pressure of the earth. 13 are pressure sensors, which together with the temperature sensor 12 serve as means for detecting wear of the cutter seal. The pressure sensor 13 is attached to the hood portion 1a at a position facing the space 9 formed before and after the plurality of rows of cutter seals 7. Although it depends on the diameter of the shield tunneling machine, it is sufficient to provide the pressure sensor 13 at one location on the circumference. The pressure sensor 13 measures the pressure of the grease sealed in each space 9, and the grease pressure in each space 9 is approximately 0.5 Kgf/cm ² at a time from the mud water pressure of the ground in order from the face side. It's getting expensive.

As the excavation work progresses, each cutter seal 7
And the amount of wear on the mating sliding surface increases. In this case, the cutter seals in the first row on the face side, which are in direct contact with the earth, sand and muddy water that constantly try to invade, will inevitably wear out the fastest. Normally, the cutter seals 7 in the second and third rows are slightly worn, and the cutter seals 7 in the first row are
Then, only the wear of the mating sliding surface progresses, and the temperature change due to the decrease in frictional heat on the sliding surface is caused by temperature sensor 1.
2 is detected. As the detected temperature decreases, the space 9 before and after the cutter seal 7 in the first row
The grease inside passes through the worn cutter seal 7 and the mating sliding surface, and gradually a state of communication is established and the pressure difference in the grease pressure disappears. At this point, the supply of grease is stopped. This also applies to the cutter seals 7 in the second and third rows. All of this pressure change is measured by the pressure sensor 13, and along with the temperature sensor 12 detecting the temperature change of the sliding surface, it is sent to the driver's seat in the shield body 1 or to the control room of the shield excavator installed in the shaft, for example, to the second It is sent and controlled via the device shown in the figure. In FIG. 2, signals from a temperature sensor 12 and a pressure sensor 13 are sent to a comparator 15 via an amplifier 14 and compared with a set temperature and a set pressure from a setter 16. When the detected temperature and measured pressure are at the set value or within a certain range close to the set value, the comparison calculation value is sent to the alarm generator 17, which issues an alarm with a lamp or buzzer and keeps the set value or set value constant. If the range is exceeded, the comparison calculation value is sent to the control device 18, and a signal S to stop the rotation and digging of the cutter wheel is output. As mentioned above, in the present invention, a temperature sensor is provided to measure the temperature of the sliding surface, and a pressure sensor is also provided to measure the pressure in the space formed before and after each cutter seal, so that changes in the temperature of the sliding surface can be detected. It is possible to measure pressure changes in the space before and after the cutter seal, and from measuring temperature and pressure changes, it is possible to accurately judge the wear status of the cutter seal and the mating sliding surface at any time.

〔Effect of the invention〕

As explained above, the present invention provides wear detection means for the cutter seal and the mating sliding surface so that the wear status thereof can be accurately determined at any time. Sufficient protection from dirt and muddy water can be achieved, and serious situations such as the cutter wheel not being able to be driven can be prevented from occurring. Moreover, the above-mentioned proper judgment enables proper excavation control, extends the life of the cutter seal, and prevents wasteful consumption of grease.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention, FIG. 2 is a block diagram showing an example of a control device based on measured values, and FIG. 3 is an explanatory diagram of an example of protection of a conventional cutter wheel drive device. 1...Shield body, 1a...Hood part, 1b
...Bulkhead, 2...Cutter foil, 3...Bearing,
5... Pinion, 6... Gear, 7, 8... Cutter seal, 9, 10... Space, 11... Chamber, 12... Temperature sensor, 13... Pressure sensor.

Claims (1)

[Claims] 1. A plurality of rows of cutter seals that prevent the intrusion of earth and sand into the shield body are rotatably attached to the shield body, and a peripheral portion of the cutter foil;
In the shield excavator, which is disposed with a space between the shield body and the shield body, a temperature sensor for measuring the temperature of the seal sliding surface of the shield body is provided on the shield body at a position facing each of the cutter seals. A cutter seal for a shield excavator, characterized in that a pressure sensor for measuring the pressure of grease sealed in the space is provided on the shield body at a position facing the space formed before and after each of the cutter seals. wear detection device.