JP2000170477A - Cutter front load detecting method and device for shield boring machine, and shield boring machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lengthen the service life of a shield boring machine by precisely stopping an advance of boring of the shield boring machine when a cutter front load becomes excessive by accurately measuring the cutter front load. SOLUTION: In a cutter front load detecting method of a shield boring machine having a cutter support structure 8 for transmitting a cutter front load S to a shield frame 1, a prescribed cutter front load S is made to act on a model of the cutter support structure 8 to predetermine the relationship between stress and displacement of model respective parts by a structural analysis, and a strain gauge 20 is arranged in a prescribed position in the cutter support structure 8 of the shield boring machine according to the generating direction of the stress obtained by the model to detect a stress 25 by the strain gauge 20 at boring advancing time of the shield boring machine to directly detect the cutter front load S the shield boring machine from a comparison between the detected stress 25 and a stress 25 of a structural analysis result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for detecting a front load of a cutter of a shield machine and a shield machine.

[0002]

2. Description of the Related Art Conventionally, a shield excavator has a center shaft supporting system for rotatably supporting a cutter head by a center shaft, an intermediate beam supporting system for rotatably supporting a cutter head by providing a turning ring on a partition wall, Alternatively, various systems such as an outer peripheral beam supporting system that rotatably supports a cutter head by an outer peripheral beam have been implemented.

FIG. 5 shows, as an example, a shield excavator of a center shaft supporting type. This shield excavator is provided with a partition wall 2 integrally provided in a radial direction inside a front end of a shield frame 1. The center shaft 4 of the cutter head 3 is rotatably penetrated in the center,
At the rear end of the center shaft 4, a cutter bearing 5 having a thrust bearing and a radial bearing built therein is fitted and arranged. The cutter bearing 5 is connected to the partition 2 by a connecting member 6 in parallel with the partition 2. Is fixed to a cutter support structure 8 composed of a partition rear side plate 7 fixed to the rear side.

[0004] A cutter head gear 9 is fixed to the center shaft 4 at a position between the partition 2 and the partition rear side plate 7. A pinion 10 meshing with the cutter head gear 9 is fixed to the partition rear side plate 7. The provided rotary drive motor 11 is fixed. In the figure, 12 is a screw, 13
Indicates a cutter bit provided on the cutter head 3.

[0005] In the shield machine shown in FIG.
The excavated soil is excavated by rotating the cutter head 3 via the pinion 10 and the cutter head gear 9 by driving the rotary drive motor 11, and the shield excavator is excavated by extending a shield jack (not shown). If the cutter front load acting on the front of the cutter head 3 can be detected, it is very useful for safely operating the shield machine and extending the life of the shield machine.

The front load of the cutter acting on the cutter head 3 includes the strength of the cutter head 3, the strength of the shield frame 1, the strength of the cutter bearing 5 supporting the cutter head 3, and the like.
This is one of the important design conditions for determining the strength and the like of the cutter support structure 8.

Conventionally, in order to detect the front load of the cutter, a rotational torque of the rotary drive motor 11 is detected, and the cutter is determined from the detected rotational torque and frictional resistance (based on an assumed friction coefficient μ of the excavated soil). The cutter front load acting on the head 3 is calculated.

[0008]

However, the conventional method for detecting the load on the cutter front face of the shield machine described above has the following problems.

That is, since the cutter front load is obtained by calculation from the rotational torque of the rotary drive motor 11 and the friction resistance of the excavated soil, the actual cutter front load acting on the front of the cutter head 3 is directly measured. Could not.

In the conventional shield machine, interlock control for stopping the excavation of the shield machine is performed when the load on the front of the cutter becomes larger than a predetermined value. In such a case, the front load of the cutter may increase more than expected, but this cannot be detected by the conventional method, so that the service life of the cutter bearing 5 is greatly reduced. Or, there is a possibility that the cutter supporting structure 8 may be deformed.

Conventionally, the friction coefficient μ for calculating the frictional resistance of the front surface of the cutter is an estimated value based on the excavated soil quality. For example, the properties of the excavated soil other than the hardness of the excavated soil, the structure of the cutter head 3, It does not take into account the shape of the cutter bit 13, the influence of the direction control of the shield machine, the appropriateness of the excavation speed, etc., and therefore, the reliability of the accuracy of the cutter front load obtained by the conventional method is low, and therefore the design load is low. There is a problem that it is not possible to design an efficient and economical design because it is not known whether the system is excessive or insufficient.

The present invention has been made to solve such a conventional problem. By accurately measuring the front load of the cutter, the remaining life of the cutter bearing can be accurately predicted, and the front load of the cutter becomes excessive. In such a case, safety can be achieved by stopping the excavation of the shield excavator precisely, the excavation speed of the shield excavator can be accurately controlled, and thus the life of the shield excavator can be extended, An object of the present invention is to provide a method and an apparatus for detecting a load on a cutter front surface of a shield machine which can be efficiently designed, and a shield machine.

[0013]

According to the first aspect of the present invention,
A method for detecting a cutter front load of a shield machine provided with a cutter support structure for transmitting a cutter front load to a shield frame, wherein a predetermined cutter front load is applied to a model of the cutter support structure to perform structural analysis of each part of the model. The relationship between stress and displacement is determined in advance, and a strain gauge is installed at a predetermined position in the cutter support structure of the shield machine in accordance with the direction in which the stress obtained by the model is generated. According to a method for detecting the front load of the cutter of the shield machine, which directly detects the front load of the cutter of the shield machine by comparing the detected stress value with the stress value of the structural analysis result. Things.

According to a second aspect of the present invention, there is provided a cutter front load detecting device for a shield excavator provided with a cutter support structure for transmitting a cutter front load to a shield frame, wherein the cutter front load detector is provided at a stress generating portion of the cutter support structure. Strain gauge and the stress value of the structural analysis result by the model of the cutter supporting structure are input in advance, and the stress value detected by the strain gauge and the stress value of the structural analysis result are compared to calculate the cutter front load. And a load detecting device for a cutter of a shield machine.

According to a third aspect of the present invention, the arithmetic unit compares the stress value detected by the strain gauge with the stress value of the structural analysis result to calculate the front load of the cutter, and calculates the remaining load of the cutter bearing from the front load of the cutter. A cutter bearing remaining life indication circuit that calculates the service life and outputs a cutter bearing remaining life warning signal based on a comparison between the remaining life of the cutter bearing and the estimated remaining digging operation time, and a cutter bearing remaining life indicating the cutter bearing remaining life warning 3. A device according to claim 2, further comprising a caution indicator.

According to a fourth aspect of the present invention, the arithmetic unit outputs the excavation stop command when the stress value detected by the strain gauge is equal to or more than the long-term allowable stress value and equal to or more than the short-term allowable stress value. The front load detecting device for a cutter of a shield machine according to claim 2 or 3, further comprising:
It is related to.

According to a fifth aspect of the present invention, the arithmetic unit includes a digging speed caution instruction circuit for outputting a digging speed caution signal when the stress value detected by the strain gauge is equal to or greater than a long-term allowable stress value.
5. A cutter front load detecting device for a shield machine according to claim 2, further comprising a machine speed warning indicator for displaying machine speed warning.

According to a sixth aspect of the present invention, there is provided a shield comprising the cutter front load detecting device according to the second or third aspect, wherein a remaining life of the cutter bearing is calculated based on the detected front load of the cutter. Excavator.

According to a seventh aspect of the present invention, there is provided a shield excavator including the cutter front load detecting device according to the second or fourth aspect, wherein the excavation stop is controlled based on the detected cutter front load. , According to.

According to an eighth aspect of the present invention, there is provided a shield excavator comprising the cutter front load detecting device according to the second or fifth aspect, wherein the excavating speed is controlled based on the detected cutter front load. , According to.

According to a ninth aspect of the present invention, there is provided a shield excavator having a structural design based on a cutter front load detected by the cutter front load detector according to the second aspect.

The operation of the above means is as follows.

According to the method and apparatus for detecting the front load of the cutter of the shield machine according to the present invention, a predetermined load on the front of the cutter is applied to the model of the cutter support structure, and the relationship between the stress and the displacement of each part of the model is obtained in advance by structural analysis. In advance, a strain gauge is installed at a predetermined position in the cutter support structure of the shield machine in accordance with the direction of the stress generated by the model, and the stress is detected by the strain meter when the shield machine is excavated, and the detected stress value By comparing this with the stress value of the structural analysis result, it is possible to directly know the front load of the cutter of the shield machine with high accuracy.

The cutter front load is calculated by comparing the stress value detected by the strain gauge with the stress value of the structural analysis result, the remaining life of the cutter bearing is calculated from the cutter front load, and the remaining life of the cutter bearing and the estimated remaining excavation are calculated. It is determined whether the remaining life of the cutter bearing is insufficient by comparing with the operating time.If the remaining life of the cutter bearing is insufficient, the cutter bearing remaining life warning signal is output and displayed. Based on the display of the service life notice, it is possible to set the excavation distance, determine the replacement timing of the cutter bearing, and the like.

When the excavation stop command is output when the stress value detected by the strain gauge is equal to or greater than the long-term allowable stress value and equal to or greater than the short-term allowable stress value, the excavation is accurately stopped when the shield excavator is overloaded. be able to.

When the stress value detected by the strain gauge becomes equal to or more than the long-term allowable stress value, the excavation speed caution signal is output and displayed, whereby the excavation speed can be accurately controlled.

The long-term allowable stress value and the short-term allowable stress value can be accurately set based on the front load of the cutter of the shield machine.

According to the shield machine equipped with the cutter front load detecting device, by accurately knowing the remaining life of the cutter bearing, the excavation distance can be set, and the time for replacing the cutter bearing can be determined accurately. In addition, when a load exceeding the proof stress is applied to the structure and mechanical elements of the shield machine due to changes in the properties of the excavated soil, etc., the magnitude of the front load of the cutter,
By reliably stopping the excavation of the shield machine based on the change, the safety of the shield machine can be enhanced. Further, since the cutter front load of the shield machine can be accurately measured, the excavation speed can be accurately controlled, and stable excavation can be performed at a safe speed.

If the shield machine is designed based on the cutter front load detected by the cutter front load detector, the shield machine can be provided with an efficient and high strength by eliminating excess and deficiency of the structural material. be able to.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an example of an embodiment of the present invention. The same parts as those of the shield machine shown in FIG. Only the features of the present invention will be described in detail.

As shown in FIG. 1, a thrust bearing 14 and a radial bearing 15 are provided at the rear end of the cutter head 3.
A cutter bearing 5 is provided, and a rear wall 7 of the partition wall constituting the cutter support structure 8 is fixed to a boss 16 of the cutter bearing 5. It is fixed to the partition 2 by the provided connection reinforcing plate 17 and is fixed to the shield frame 1 by the connection strength member 18. Further, a plurality of radially extending rear reinforcing plates 19 are fixed between the rear surface of the partition rear plate 7 and the outer peripheral surface of the boss 16 of the cutter bearing 5.

At a required position of the rear reinforcing plate 19, a strain gauge 2
Set 0. The required number of the strain gauges 20 can be installed on the plurality of rear reinforcing plates 19 provided.

In FIG. 1, a strain gauge 20 is also provided on a connection reinforcing plate 17 connecting between the partition 2 and the rear wall 7 of the partition.

FIG. 3 shows a model 21 of the rear reinforcing plate 19 and the connecting reinforcing plate 17 of the cutter supporting structure 8.
The state where the rear reinforcing plate 19 and the connecting reinforcing plate 17 are deformed from a broken line state to a solid line state when a cutter front load S of a predetermined size assumed by excavation is applied to the model 21 is exaggeratedly shown. .

FIG. 4 shows the model 21 as shown in FIG.
FIG. 9 is a front view showing an example in which the rear reinforcing plate 19 and the connecting reinforcing plate 17 are subjected to a structural analysis using a finite element method when a predetermined cutter front load S is applied to the cutter. You can ask for a relationship.

The rear reinforcing plate 19 and the connecting reinforcing plate 17 are
As shown by an arrow in FIG. 4, a large tensile stress is applied, and the strain is adjusted in the direction of the arrow so that a stress in a relatively large tensile stress can be detected in a direction parallel to the direction of the arrow. A total of 20 are installed.

As shown in FIG. 1 and FIG.
The displacement amount 22 detected by 0 is input to each of the stress detectors 23, and the data D of the cutter supporting structure 8 is input to each of the stress detectors 23, so that the respective The stress value 25 at the point is determined.

The stress value 25 determined by the stress detector 23 corresponds to the cutter front load S. Therefore, the detected stress value 25 and the stress value 24 of the structural analysis result determined by the model 21 are used. By inputting to the arithmetic unit 26, the cutter front load S of the shield machine is obtained, and thereby various commands and instructions are performed.

Further, between the fixing member 27 fixed to the rear end of the boss 16 of the cutter bearing 5 and the upper end of the rear reinforcing plate 19, the longitudinal displacement of the cutter supporting structure 8 is measured. A displacement meter 28 is provided, and a displacement signal 29 from the displacement meter 28 is input to the stress detector 23, and the stress value 24 of the structural analysis result and the detected stress value 25 are calculated based on the displacement signal 29. This is to support the relationship.

The arithmetic unit 26 is provided with a cutter bearing remaining life indicating circuit 44 as shown in FIG. The cutter bearing remaining life indicating circuit 44 outputs the recorded stress value 25 ′ from the recorder 31 that continuously records the stress value 25.
And a calculator 45 for calculating the cutter front load S by inputting and comparing the stress value 24 of the analysis result, and a calculator 46 for calculating the remaining life P of the cutter bearing from the obtained cutter front load S. And a comparator 48 for comparing the obtained remaining life P of the cutter bearing with the estimated remaining digging operation time 47, and inputting the comparison result and outputting a cutter bearing remaining life warning signal 49 when the remaining life of the cutter bearing is insufficient. And a determination circuit 50 for performing the determination. Further, a cutter bearing remaining life warning indicator 51 for displaying a cutter bearing remaining life warning signal 49 from the determination circuit 50 is provided.

The arithmetic unit 26 is provided with an excavation stop command circuit 30 (interlock circuit). The excavation stop command circuit 30 includes a determination circuit 32 for inputting a recorded stress value 25 ′ from a recorder 31 that continuously records the stress value 25, and a stress value from the stress detector 23. 25 is provided, and
When the stress value 25 ′ recorded in the judgment circuit 32 is equal to or more than the long-term allowable stress value 34 and the stress value 25 is equal to or more than the short-term allowable stress value 35 in the judgment circuit 33, the excavation stop command 36 is output. Has become. The recorder 3
The recorded stress value 25 'from 1 is the long-term allowable stress value 34
In the following cases, the steady excavation 37 is performed, and when the stress value 25 is equal to or less than the short-term allowable stress value 35, the excavation speed reduction 38 is performed.

Further, the arithmetic unit 26 is provided with a digging speed caution instruction circuit 39. Excavation speed caution instruction circuit 39
A display 40 provided on an operation panel for displaying the stress value 25 ′ from the recorder 31, and a digging speed caution signal 4 when the stress value 25 ′ becomes equal to or greater than the long-term allowable stress value 34.
And a decision circuit 42 for outputting 1. Further, there is provided a digging speed caution indicator 43 for displaying a digging speed caution signal 41 from the judgment circuit 42.

The long-term allowable stress value 3 of the stress value 25 'described above
4, and the short-term allowable stress value 35 of the stress value 25 is the cutter front load S of the shield machine calculated by the calculator 45.
Can be set based on.

The operation of the above embodiment will be described below.

A model 21 of the cutter supporting structure 8 as shown in FIG. 3 is prepared, and a load corresponding to the set front load of the cutter is applied to the model 21, and as shown in FIG. The relationship between the stress acting on the cutter supporting structure 8 and the displacement is determined in advance by structural analysis.

As shown in FIG. 1, a strain gauge 20 is provided at a location where a relatively large stress is generated in the cutter support structure 8 of the shield machine, and the strain gauge 20 is used by the strain gauge 20 when the shield machine is excavated. The displacement 22 of the installation part is detected. At this time, the strain gauge 20 is arranged at a position where a large tensile stress is applied as shown by an arrow in FIG.

The displacement 22 of the cutter support structure 8 is detected by the strain gauge 20, and the displacement 22 is input to a stress detector 23 to input data D such as the thickness and strength of the cutter support structure 8. The stress value 25 is calculated. At this time,
By inputting the displacement signal 29 from the displacement meter 28 to the stress detector 23, the relationship between the stress value 24 of the structural analysis result and the detected stress value 25 can be confirmed, and the stress detected by this can be confirmed. The reliability of the value 25 can be increased.

The stress value 25 for detecting the stress of the cutter support structure 8 accurately represents the magnitude and change of the front load S of the cutter acting on the shield machine.
The stress value 25 is detected, and the stress value 24 of the structural analysis result is obtained.
, The cutter front load S of the shield machine can be directly known with high accuracy.

The stress value 25 from the stress detector 23 is shown in FIG.
Cutter bearing remaining life indicating circuit 44 of the arithmetic unit 26 shown in FIG.
Excavation stop command circuit 30 and excavation speed caution instruction circuit 3
9 and the stress value 25, that is, the front load S of the cutter.
Are issued.

Stress value 2 continuously recorded by recorder 31
5 ′ is input to the calculator 45 of the cutter bearing remaining life indicating circuit 44. Further, the stress value 24 of the structural analysis result is input to the calculator 45, and the recorded stress value 2
By comparing 5 ′ with the stress value 24 of the structural analysis result, the cutter front load S is calculated. The cutter front load S is input to the calculator 46, and the remaining life P of the cutter bearing is calculated. The remaining life P of the cutter bearing and the estimated remaining digging operation time 47 are compared by a comparator 48, and a determination circuit 50 determines whether or not the remaining life of the cutter bearing is insufficient. If the cutter bearing remaining life is insufficient, the cutter bearing remaining life warning signal 49 is output to the cutter bearing remaining life warning indicator 51 to display the cutter bearing remaining life warning. Therefore, the setting of the excavation distance, the determination of the replacement time of the cutter bearing, and the like can be performed based on the indication of the remaining life of the cutter bearing.

In the excavation stop command circuit 30, the stress value 25 ′ continuously recorded by the recorder 31 is the long-term allowable stress value 3.
When the stress value is not more than 4, the steady excavation 37 is performed.
If the stress value 25 is less than or equal to the short-term allowable stress value 35, the excavation speed is reduced 38 to cope with it.

The recorded stress value 25 'is not less than the long-term allowable stress value 34 and the stress value 25 is the short-term allowable stress value 3
When it becomes 5 or more, the excavation stop command 36 is output and the excavation of the shield excavator is stopped. As described above, the stress of the cutter support structure 8 is directly detected, and when the stress value exceeds a predetermined value, the excavation of the shield excavator is stopped. When a load greater than the proof stress is applied to the structure and machine elements of the excavator, the excavation of the shield excavator can be reliably stopped, so that the life of the bearings can be significantly reduced, and the cutter support structure 8 can be bent. Such a problem can be reliably prevented, and the safety of the shield machine can be improved.

The long-term allowable stress value 3 of the stress value 25 'described above
4 and the short-term allowable stress value 35 of the stress value 25 are calculated by the calculator 4
The setting can be accurately performed based on the cutter front load S of the shield excavator calculated in step 5, and the excavation can be accurately stopped while maintaining the safety of the shield excavator.

Since the magnitude of the front load S of the cutter differs in the circumferential direction of the cutter head 3 and fluctuates, a plurality of strain gauges 20 are arranged in the circumferential direction of the cutter support structure 8. Displacement 22 detected by each strain gauge 20
The excavation stop command 36 can be controlled by using a value having the largest value (the largest stress value). Further, control may be performed based on the average value of the stress values 25 obtained from the plurality of strain gauges 20 through the stress detector 23, or the control may be performed by selecting the stress value 25 from an arbitrary strain gauge 20. It can also be used.

The stress value 25 ′ recorded in the recorder 31.
Is input to the excavation speed caution instruction circuit 39, and when the recorded stress value 25 ′ becomes equal to or greater than the long-term allowable stress value 34, the judgment circuit 42
1 is output. Further, the excavation speed caution signal 41 is output to the excavation speed caution indicator 43 to display the excavation speed caution. Therefore, by adjusting the excavation speed based on the display of the excavation speed caution indicator 43 so that the display disappears, stable excavation work can be performed at a safe excavation speed. Also in this case, the long-term allowable stress value 34 of the stress value 25 'can be set with high accuracy based on the cutter front load S of the shield machine calculated by the calculator 45, and therefore, the excavation speed of the shield machine can be improved. Can be instructed with high precision.

On the other hand, since the stress value 25 is continuously recorded by the recorder 31 as described above, by utilizing the recorded stress value 25 ', the cutter of the newly planned shield machine can be used. Configurations such as the strength of the head 3, the strength of the shield frame 1, and the strength of the cutter bearing 5 can be efficiently designed.

In the above embodiment, the shield shaft excavator of the center shaft supporting type in which the cutter head is rotatably supported by the center shaft has been described. Of course, and various changes can be made without departing from the scope of the present invention.

[0059]

According to the method and the apparatus for detecting the front load of the cutter of the shield machine according to the present invention, the relationship between the stress and the displacement of each part of the model is determined by applying a predetermined front load to the model of the cutter support structure by the structural analysis. In advance, a strain gauge is installed at a predetermined position in the cutter support structure of the shield machine in accordance with the direction of the stress generated by the model, and the stress value is detected by the strain meter when the shield machine is excavated and detected. By comparing the obtained stress value with the stress value of the structural analysis result, there is an effect that the front load of the cutter of the shield machine can be directly known with high accuracy.

The cutter front load is calculated by comparing the stress value detected by the strain gauge with the stress value of the structural analysis result, the remaining life of the cutter bearing is calculated from the cutter front load, and the remaining life of the cutter bearing and the estimated remaining excavation are calculated. It is determined whether the remaining life of the cutter bearing is insufficient by comparing with the operating time.If the remaining life of the cutter bearing is insufficient, the cutter bearing remaining life warning signal is output and displayed. Based on the display of the service life notice, there is an effect that the excavation distance can be set, the replacement timing of the cutter bearing can be determined, and the like.

When the excavation stop command is output when the stress value detected by the strain gauge is equal to or greater than the long-term allowable stress value and equal to or greater than the short-term allowable stress value, the excavation is properly stopped when the shield excavator is overloaded. There is an effect that can be.

When the stress value detected by the strain gauge becomes equal to or more than the long-term allowable stress value, the excavation speed caution signal is output and displayed, whereby the excavation speed can be controlled accurately.

According to the shield excavator equipped with the cutter front load detecting device, it is possible to accurately set the excavation distance and determine the replacement timing of the cutter bearing by accurately knowing the remaining life of the cutter bearing. There is. In addition, when a load exceeding the proof stress is applied to the structure and mechanical elements of the shield machine due to changes in the properties of the excavated soil, etc., the excavation of the shield machine must be stopped based on the magnitude and change of the front load of the cutter. Thereby, there is an effect that the safety of the shield machine can be enhanced. Further, since the cutter front load of the shield machine can be measured with high accuracy, the excavation speed can be accurately controlled, and there is an effect that stable excavation can be performed at a safe speed.

If the shield machine is designed based on the cutter front load detected by the cutter front load detector, an efficient and high strength shield machine can be provided by eliminating excess or deficiency of the structural material. There is an effect that can be.

[Brief description of the drawings]

FIG. 1 is a cut-away side view showing an example of an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an example of an arithmetic device in FIG. 1;

FIG. 3 is a front view showing an example of a model according to the present invention.

FIG. 4 is a front view showing an example of a structural analysis of the model of FIG. 3 by a finite element method.

FIG. 5 is a cut-away side view showing an example of a conventional shield machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shield frame 8 Cutter support structure 20 Strain gauge 21 Model 23 Stress detector 24 Stress value of structural analysis result 25 Detected stress value 25 'Recorded stress value 26 Arithmetic unit 30 Excavation stop command circuit 34 Long-term allowable stress value 35 Short-term allowable stress value 36 Drilling stop command 39 Drilling speed caution instruction circuit 41 Drilling speed caution signal 43 Drilling speed caution indicator 44 Cutter bearing remaining life indication circuit 47 Estimated remaining excavation operating time 49 Cutter bearing remaining life warning signal 51 Cutter bearing remaining life Caution indicator S Front load of cutter P Remaining life of cutter bearing

Continued on the front page (72) Inventor Hiroyuki Ito 111-1 Kitahama-cho, Chita-shi, Aichi Prefecture Harima Heavy Industries Co., Ltd. Aichi Factory (72) Inventor Toshio Suzuki 11-1 Kitahama-cho, Chita-shi, Aichi Prefecture Harima Ishikawajima Heavy Industries Company Aichi Factory (72) Inventor Tomio Nishi 11-1 Kitahama-cho, Chita-shi, Aichi Prefecture Ishikawajima-Harima Heavy Industries Co., Ltd. Aichi Factory F-term (reference) 2D054 GA08 GA17 GA64 GA81 2F051 AA06 AB09 AC01 AC07

Claims (9)

[Claims] 1. A method for detecting a front load of a cutter of a shield machine comprising a cutter support structure for transmitting a front load of a cutter to a shield frame, wherein a predetermined front load of the cutter is applied to a model of the cutter support structure. The relationship between stress and displacement of each part of the model is obtained in advance by analysis, and a strain gauge is installed at a predetermined position in the cutter support structure of the shield machine in accordance with the direction of the stress generated by the model, and the shield machine is installed. Detecting the stress by the strain gauge during excavation, and directly detecting the cutter front load of the shield excavator by comparing the detected stress value with the stress value of the structural analysis result; Detection method. 2. A cutter front load detection device for a shield excavator provided with a cutter support structure for transmitting a cutter front load to a shield frame, comprising: a strain gauge installed at a stress generating portion of the cutter support structure; A stress value of a structural analysis result based on a model of the support structure is input in advance, and a calculating device capable of calculating a cutter front load by comparing the stress value detected by the strain gauge with the stress value of the structural analysis result is provided. A load detecting device for a cutter front surface of a shield machine. 3. The arithmetic unit calculates the front load of the cutter by comparing the stress value detected by the strain meter with the stress value of the structural analysis result, calculates the remaining life of the cutter bearing from the front load of the cutter, and calculates the remaining life of the cutter bearing. Equipped with a cutter bearing remaining life indication circuit that outputs a cutter bearing remaining life warning signal based on a comparison between the remaining life of the cutter bearing and the estimated remaining digging operation time, and a cutter bearing remaining life warning indicator that indicates the remaining life of the cutter bearing. The front load detecting device for a cutter of a shield machine according to claim 2, wherein: 4. The arithmetic unit includes an excavation stop command circuit that outputs an excavation stop command when the stress value detected by the strain gauge is equal to or greater than a long-term allowable stress value and equal to or greater than a short-term allowable stress value. The cutter front load detecting device for a shield machine according to claim 2 or 3, wherein: 5. A digging speed caution instruction circuit for outputting a digging speed caution signal when a stress value detected by a strain gauge becomes equal to or more than a long-term allowable stress value, and a digging speed caution for displaying a digging speed caution. The front load detecting device for a cutter of a shield machine according to claim 2, further comprising an indicator. 6. A shield excavator comprising the cutter front load detecting device according to claim 2 or 3, wherein a cutter bearing remaining life is calculated based on the detected cutter front load. 7. A shield excavator comprising the cutter front load detection device according to claim 2 or 4, wherein excavation stoppage is controlled based on the detected cutter front load. 8. A shield excavator comprising the cutter front load detection device according to claim 2 or 5, wherein the excavation speed is controlled based on the detected cutter front load. 9. A shield excavator having a structural design based on a cutter front load detected by the cutter front load detector according to claim 2.