JPH0258434B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling the excavation speed of a shield tunneling machine.

Generally, as shown in FIGS. 1 and 2, a shield tunneling machine has a cutter wheel 9 rotatably attached to the front opening of a cylindrical shield hull 7, and this cutter wheel 9 is connected to a drive motor 10. ,
The required number, for example, 12, is installed in the shield hull 7.
A book (usually 6 to 20) of shield jack J ₁ ,
J ₂ , J ₃ ...J ₁₂ are arranged at equal intervals along the circumference of the shield hull 7. These 12 shield jackets
J ₁ , J ₂ , J ₃ ...J ₁₂ are connected to a hydraulic power source (not shown) via a jack selection switching valve and a pressure oil supply section (not shown). Furthermore, a screw conveyor 11 as an earth and sand discharge device is provided in the shield hull 7.
is arranged. Said shield jacket
While extending a predetermined shield jack among J ₁ , J ₂ , J ₃ , ... J ₁₂ , the cutter wheel 2 is rotated to excavate the ground, and the excavated earth and sand is once taken into the shield hull 7, Furthermore, it is discharged to the outside of the machine by a screw conveyor 11 and excavated.

In such a shield excavator, not all of the equipped shield jacks J ₁ , J ₂ , J ₃ ...J ₁₂ are always used, but the number of jacks to be used is changed by switching the jack selection switching valve according to the excavation direction and thrust. This is to adjust which part of the shield jack is used. Adjust this with reference to FIG. In the figure, open circles indicate shield jacks that are used, and circles with lattice hatching indicate shield jacks that are not used. Here, if you want to turn the shield tunneling machine to the right when viewed from the tail side, use shield jacks J ₈ to J ₁₂ as shown in (a),
If you want to point it to the left, use shield jacks J ₂ to _{J 6} as shown in (b), and if you want it to point upwards, use
Use shield jacks J ₅ to _{J 9} as shown in (c), and when you want to point it downward, use shield jacks J ₁ , J ₂ , J ₃ , J ₁₁ , J ₁₂ as shown in (d). If you want to increase the thrust, use shield jacks J ₂ , J ₃ , J ₅ , J ₆ , J ₈ , J ₉ , J ₁₁ , J ₁₂ as shown in (e).
If you want to further reduce the thrust, use shield jacks J ₁ , J ₄ , J ₇ , and J ₁₀ as shown in (f).

In addition, in FIG. 2, the number and locations of the shield jacks used are just an example, and are not limited to those shown in FIG.

The shield tunneling machine illustrated in Fig. 1 is of the earth pressure type, but other types, such as those of the muddy water pressurization type, can also be used to change the direction of the shield tunneling machine using a shield jack. It also adjusts the thrust.

However, the above-mentioned shield excavator has the following drawbacks because it simply connects a plurality of shield jacks to one hydraulic machine via a jack selection switching valve and a pressure oil supply section. ing.

1. The extension speed of the shield jack, that is, the digging speed, is determined by the amount of pressure oil supplied and the number of jacks used.

Here, if the expansion speed of the shield jack is V, the expansion speed V is expressed by the following formula.

V=Q/nA However, Q is the amount of pressure oil supplied from the hydraulic source, n is the number of jacks used, and A is the cross-sectional area of the jacks. Therefore, when setting or adjusting the excavation speed V, the operator must always check the number n of jacks used. This is inconvenient because the pressure supply amount Q must be adjusted while taking this into consideration.

2. Changing the number of jacks used during excavation will cause a sudden change in the excavation speed, but such a sudden change in excavation speed will cause a sudden change in the earth pressure or water pressure at the face, and this sudden change in earth pressure or water pressure can cause the collapse of the face. It is dangerous and may cause damage.

3. If the mud water shield or earth pressure shield is configured to maintain mud water pressure or earth pressure constant by automatically adjusting the volume of discharged mud water or discharged soil, the above-mentioned excavation speed Sudden changes in mud water pressure or earth pressure may cause disturbances and impair the stability of automatic control.

4. Due to the above-mentioned collapse of the face and instability of automatic control, it is not possible to freely change the number of jacks used during excavation.

The present invention aims to provide an excavation speed control device that improves the above-mentioned drawbacks.

In order to achieve the above-mentioned objects, the present invention comprises: an excavation speed setting means for setting the excavation speed of a shield excavator; an elongation speed detection means for detecting an elongation speed of a shield jack; calculation means for outputting a control signal for making the extension speed detection means equal to the excavation speed setting signal based on the output signal from the speed detection means; and supply of pressure fluid from the pressure oil supply section based on the output signal of the calculation means. The invention is characterized in that it is provided with a means for controlling the amount of shield jacks, and is configured so that a set digging speed can be obtained regardless of the number of shield jacks used.

Hereinafter, two examples of the excavation speed control device for a shield excavator according to the present invention will be described with reference to FIGS. 3 and 4.

FIG. 3 is a hydraulic/electrical circuit diagram showing a first embodiment of the excavation speed control device of the present invention.

In the figure, J ₁ , J ₂ , J ₃ ...Jn are the appropriately required number of shield jacks, and the bottom side of the appropriately required number of shield jacks J ₁ , J ₂ , J ₃ ...Jn is for jack selection. While connecting the switching valves 12 respectively, n
An automatic follow-up switching valve 13 and a pressure reducing valve 14 are connected in parallel to the jack selection switching valve 12 on the bottom side of the th shield jack Jn. The jack selection switching valve 12, the automatic follow-up switching valve 13, and the pressure reducing valve 14 are connected to the oil pump 8 via the shield jack operating direction switching valve 15 and the flow rate control valve 5.
Connect to. Note that the reference numeral 16 in the figure is an electric motor for driving the oil pump 8.

Therefore, the excavation speed control device of the present invention in this embodiment includes an excavation speed setting means 1 that sets the excavation speed V ₀ of the shield excavator and outputs the setting signal V ₀ , and an n-th shield excavator Jn. In conjunction with the piston rod, the shield jack J ₁ ,
J ₂ , J ₃ ...Detect the elongation speed V _f of Jn and output the detection signal V _f
an elongation speed detection means 2 for outputting, and connected to the elongation speed detection means 2 and the excavation speed setting means 1;
A control signal H ₍ for _{example , V 0 and}
A calculation means 3 that outputs a difference in V _f and an amplifier 4 that increases or decreases proportionally.

The excavation speed control device of the present invention in this embodiment has the above configuration, and its operation will be explained below.

First, during excavation, if the number of jacks in use is increased by switching the jack selection switching valve 12, the digging speed, that is, the extension speed V _f of the shield jack, tends to decrease by the increase in the number of jacks in use. , the difference between the set speed V ₀ and the extension speed V _f of the shield jack expands to the positive side, the control signal H from the calculation means 3 increases, the opening degree of the flow control valve 5 increases, and the amount of pressure applied to the jack in use increases. The amount of pressure oil supplied increases. As a result, the extension speed of the shield jacket V _f
is maintained at the set speed V ₀ without decreasing. Also, if the number of jacks used is reduced, the digging speed, that is, the extension speed V _f of the shield jack, will increase by the decrease in the number of jacks used, but the set speed V ₀ and the extension speed of the shield jack The difference with V _f widens to one side, the control signal H from the calculation means 3 decreases, the opening degree of the flow control valve 5 decreases, and the amount of pressure oil supplied to the jack in use decreases. As a result, the extension speed V _f of the shield jack does not increase and is maintained at the set speed V ₀ .

In this way, when the number of jacks used is increased or decreased, the amount of pressure oil supplied to the shield jacks is automatically increased or decreased, and the extension speed of the shield jacks V _f ,
In other words, the excavation speed is configured to maintain the set speed _V0 . Therefore, there is no inconvenience like the conventional method of adjusting the supply amount of pressure oil while taking into account the number of jacks used. In addition, the expansion speed of the shield jack
Since V _f is approximately constant at the set speed V ₀ , it is possible to prevent the face from collapsing due to sudden changes in excavation speed, and there is no disturbance in water pressure or earth pressure, and the amount of drained mud water or discharged sediment is automatically adjusted. The stability of automatic control can be ensured. Furthermore, by preventing the collapse of the face and establishing the stability of automatic control, the number of jacks used can be freely changed.

The aforementioned automatic follow-up switching valve 13 and pressure reducing valve 14
Even when the n-th shield jack Jn equipped with the extension speed detection means 2 is not selected, the pressure reducing valve 1
The pressure oil that has passed through 4 causes the shield jack Jn
is configured so that it can be extended without generating thrust and the extension speed can be detected.

FIG. 4 is a hydraulic/electrical circuit diagram showing a second embodiment of the excavation speed control device of the present invention.

The excavation speed control device of the present invention in this embodiment uses a variable speed electric motor 17 as the electric motor for driving the oil pump 8, and a rotation control device 6 is connected between the variable speed electric motor 17 and the calculation means 3. Interpose. Therefore, when the control signal H from the calculation means 3 is input to the rotation control device 6, the control signal H
The rotation control device 6 proportionally controls the variable speed electric motor 1.
7 is increased or decreased, and as a result, the discharge amount of the oil pump 8, that is, the supply amount of pressure oil is increased or decreased, and the same effect as in the case of the first embodiment described above can be obtained.

As is clear from the above embodiments, the excavation speed control device of the present invention detects the expansion speed of the shield jack and controls the supply amount of pressure oil, so that the amount of pressure oil supplied is always constant regardless of the number of shield jacks used. Since it is configured to maintain the extension speed of the shield jack, that is, the digging speed, there is no inconvenience such as having to adjust the supply amount of pressure oil while considering the number of jacks in use. Furthermore, since the excavation speed can be kept constant during excavation, collapse of the face due to sudden changes in the excavation speed can be prevented, and the stability of automatic control can be ensured. Moreover,
The number of jacks used can be changed freely.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a shield excavator, and FIGS. 2 a to 2 f are explanatory diagrams showing how the shield jack is used. FIG. 3 is a hydraulic/electrical circuit diagram showing a first embodiment of the excavation speed control device for a shield tunneling machine of the present invention, and FIG. 4 shows a second embodiment of the excavation speed control device of the present invention. This is a hydraulic and electrical circuit diagram. DESCRIPTION OF SYMBOLS 1... Excavation speed setting means, 2... Extension speed detection means, 3... Calculating means, 4... Amplifier, 5... Flow rate control valve, 6... Rotation control device, 7... Shield hull, 8... Oil pump, 9...Cutter wheel, 12...Judge selection switching valve, 16...Electric motor, 17...Variable speed electric motor, _J1 , _J2 , _J3 ...Jn...
...Shield Jack.

Claims (1)

[Claims] 1. A cutter wheel is rotatably installed in the opening on the entire surface of the shield hull, and the required number of shield jacks are arranged inside the shield hull, and each shield jack is supplied with hydraulic pressure via a single pressure oil supply section. In the shield tunneling machine connected to the power source, a tunneling speed setting means for setting the tunneling speed of the shield tunneling machine and outputting a setting signal, and a tunneling speed setting means that is connected to the shield jack and detects the extension speed of the shield jack. An elongation speed detection means for outputting the detection signal, and an elongation speed detection means connected to the elongation speed detection means and the excavation speed setting means, and an elongation speed detection signal based on the setting signal from the excavation speed setting means and the detection signal from the elongation speed detection means. and means for controlling the amount of pressure oil supplied from the pressure oil supply section based on the output signal of the calculation means. An excavation speed control device for a shield excavator, characterized in that it is configured so that a set excavation speed can be obtained regardless of the number of used shield excavators.