JP2553720Y2 - Buckling prevention device for shield machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing buckling of a shield machine, which prevents buckling of a shield body.

[0002]

2. Description of the Related Art Conventionally, a shield machine for excavating a tunnel has a plurality of shield jacks in a circumferential direction of a shield body, and the tunnel body is excavated by propelling the shield body with these shield jacks. ing.

When each shield jack extends to the stroke end and excavation for one pitch is completed, the shield jacks are sequentially contracted to assemble the segments. A so-called buckling occurs in which the shield body retreats due to pressure and muddy water pressure, and the tail seal is damaged. For this reason, in the past, the hydraulic circuit of the shield jack was divided into a plurality of systems, and a detector was provided for each system, or a pressure sensor was provided for each shield jack and the shrinkage of the shield jack was detected, so that buckling on the shield body was achieved. It is prevented from occurring.

[0004]

However, in the conventional method in which the hydraulic circuit of the shield jack is divided into a plurality of circuits or a pressure detector is provided for each shield jack, the circuit becomes complicated and the apparatus itself becomes expensive. However, there is a problem that a lot of space is required for installation. The present invention has been made in order to improve the above-mentioned conventional problems, and has as its object to provide a buckling prevention device for a shield machine which can prevent buckling of a shield body with a simple device. It is.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a tunnel in which a shield body is propelled into the ground by a plurality of shield jacks provided along the inner periphery of the shield body. In a shield machine that excavates a shield jack provided along the inner periphery of the shield body is divided into a plurality of groups and contraction operation patterns are respectively set, and according to these contraction operation patterns, each shield jack contracts, and A buckling prevention device for a shield jack machine which prevents a shield jack erroneously selected by an interlock circuit from contracting when a shield jack not corresponding to the contraction operation pattern is selected when a contraction operation pattern is selected.

According to this invention, the magnitude of the earth pressure and water pressure from the cutting face side on the shield machine can be known in advance by the number of the supported shield jacks and the hydraulic pressure. Shield jacks are divided into multiple contraction operation patterns, which are divided into multiple contraction operation patterns. Since the amount of increase in the force applied to the shield jack is known in advance, if the contraction operation pattern of the shield jack corresponding to this is selected, the shield jack does not buckle. Therefore, while the shield machine does not buckle during segment assembly, the segment can be assembled smoothly, and even if a shield jack that does not correspond to the contraction operation pattern is selected,
Since the interlock circuit prevents the shield jack erroneously selected from contracting, the operability for eliminating buckling due to an operation error can be improved. In addition, since it is only necessary to provide a simple interlock circuit, it can be implemented easily and inexpensively.
Since little space is required for installation, it can be adopted regardless of the diameter of the shield machine.

[0007]

An embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a layout diagram of a shield jack arranged in a shield jack body, FIG. 2 is a hydraulic circuit diagram of the shield jack, and FIG. 3 is a circuit diagram showing an electric interlock circuit. In Figure 1 1 is a shield body, to a plurality of, for example, 2 ₁ eight shield jacks along the inner peripheral surface 2 ₈
Are arranged at equal intervals, and these shield jacks 2
Shield body 1 is adapted to be driven into the ground by _one or two _8.

[0008] In addition, FIG. 2 in 3 is the shield jack _{2 1}
In to a hydraulic pump for supplying hydraulic pressure to 2 _8, the discharge pressure of the hydraulic pump 3 after being pressure regulated by the relief valve 4, to 2 ₁ each shield jacks through line 6 by main selector valve 5 2 ₈ rod It is supplied to the chamber 2a side, also with and is supplied to the bottom chamber 2b via line 7 which is connected to the bottom chamber 2b of each shield jacks 2 ₁ to 2 _8, to 2 ₁ each shield jacks 2 ₈ bottom chamber 2b solenoid valve in the middle of the connected pipe 7 side 8
Are installed respectively.

A check valve 10 and a relief valve 11, which flow only from the solenoid valve 8 to the tank 9 side, are provided in the middle of a pipe 6 connecting the main switching valve 5 and each solenoid valve 8. The return line 12 is connected.

On the other hand to shield jacks 2 ₁ eight above 2 ₈ is set to four patterns of selection patterns, for example, vertically and horizontally during contraction operation. That is, the right pattern is 4
Constructed according to the present of the shield jacks _{2 1,} 2 _2, 2 3, _{2 4,} the left pattern shield jacks _{2 5, 2} 6, 2
It is composed of _{7, 2 8.} Furthermore the upper pattern is composed of shield jacks _{2 1,} 2 _2, 2 7, _{2 8,} the lower pattern is composed of _{2 3,} 2 _4, 2 5, _{2 6.}

[0011] and _{2 2 to} each shield jack to _{2 8}
Be configured interlock circuit the switches group S ₁ provided for each shown in FIG. 3 by S _8, the shield jacks 2 ₁ to 2 ₈ when the signal at the output terminal 14 of the interlock circuit is outputted Shrinkage can be performed.

[0012] Next In operation, conduit 7 connected to the bottom chamber 2b of the respective shield jacks 2 ₁ to 2 ₈
In by the opening at the same time the solenoid valve 8 provided, is supplied to the to the discharge pressure of the hydraulic bottom 3 2 ₁ each shield jacks via line 7 from the main switching valve 5 2 ₈ the bottom chamber 2b of the, whereby each shield jack _{2 1} to _{2 8}
Extend, and the shield body 1 is propelled. During excavation, the propulsion pressure is held by the leaf valve 11 provided in the return pipe line 12, and buckling of the shield body 1 is prevented.

[0013] When the shield jacks 2 ₁ to 2 ₈ is one pitch extends to the stroke end drilling is completed, to shield jacks 2 ₁ contracts a portion of 2 ₈ to assemble the segments, but this time When to shield jacks 2 ₁ to contract wrong choice of 2 ₈ tail seal buckling occurs in the shield body 1 is damaged.

If the shield jacks 2 _3, 2 _4, 2 ₅ is contracted to assemble now segments to prevent buckling of the shield body 1 in the following manner, the lower pattern of the jack selection pattern [0014] Therefore, in this invention . This shield jacks _{2 3,} 2 4, _{2 5} switches _S 3 corresponding _to, S 4, but to turn on _{S 5,} shield jacks ₂ 1 other than lower pattern this _{time, 2} 2,
When 2 _7, is selected by mistake even _{2 8} one, these shield jacks _{2 1,} 2 _2, 2 7, switch _S 1 corresponding to _{2 8,} S _2, S 7, _{S 8} is turned on since the normally closed contacts of these switches are turned off, no output is contracted permission signal to the output terminal 14 of the interlock circuit, the shield jacks 2 _3, 2 4, _{2 5,} 2 ₆ of the contraction can not.

Therefore, the shield jack 2 which contracts again
By ₁ to confirm the selection of the 2 _8, shield jacks 2 ₁ to buckling of the shield body 1 by selection incorrectly 2 ₈ will be able to prevent. Be selected left pattern so as to contract the same manner shield jacks ₂ 6, _{2 7} or less, erroneous shield jacks _{2 1, 2} 2,
When 2 _3, 2 is also selected in one of the _4, for shrinking enable signal from the interlock circuit is not output, with no possible contraction of the shield jacks 2 _6, 2 _7, the shield jacks 2 _1, 2 ₂ When returning, the operation can be performed only when the right pattern or the shield jack of the upper pattern is selected.

In the above embodiment, the operation pattern is set to the right,
The four patterns of left, upper, and lower are used, but the present invention is not limited thereto. Of course, the interlock circuit is also changed by changing the operation pattern.

[Brief description of the drawings]

FIG. 1 is an arrangement view showing an arrangement of a shield jack of a shield machine according to an embodiment of the present invention.

FIG. 2 is a hydraulic circuit diagram of the shield jack.

FIG. 3 is a circuit diagram of an interlock circuit.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 shield body 2 ₁ shield jack 2 ₂ shield jack 2 ₃ shield jack 2 ₄ shield jack 2 ₅ shield jack 2 ₆ shield jack 2 ₇ shield jack 2 ₈ shield jack

Claims (1)

(57) [Scope of request for utility model registration] The shield body (1) is provided by a plurality of shield jacks provided along the inner periphery of the shield body (1).
Excavator that excavates tunnels by excavating the tunnel into the ground, divides each shield jack provided along the inner periphery of the shield body (1) into a plurality of groups, and sets respective contraction operation patterns. and erroneous with each shield jacks are contracted according to these shrinkage operation pattern, when the contraction operation <br/> pattern selection, optionally the shield jacks is selected that does not correspond to the contraction operation pattern interlock circuit
A buckling prevention device for a shield jack machine that prevents the selected shield jack from contracting.