JPH0352875Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is a muddying material injection device for a mudding type shield configured to inject muddying material mainly composed of clay, bentonite, etc. into the front surface of a cutter. This is related to.

(Prior art) Conventionally, in this type of mud-adding type shield, a mud-adding pipe connecting passage that passes through the cut drum and the shield body is sandwiched between the rotating cutter drum and the fixed shield body. , inner diameter side and outer diameter side mud adding seals each having the same withstand pressure were interposed to form a rotary joint of the mud adding material injection device.

(Problem to be solved by the invention) In a conventional mud shield, when mud material is passed between the mud seals on the inner and outer diameter sides, both mud seals have the same pressure resistance, so the clay There is a risk that the muddy material, which is similar to earth and sand mixed with sand, bentonite, and sometimes sand, may flow back through the inner diameter muddying seal to the bearing and drive parts of the cutter, which are important parts of the fuselage.

Furthermore, although the muddy material is fed under pressure from the muddying pump to the muddying pipe, the pressure control is not always perfect due to some kind of malfunction or mistake in the related equipment.
Pressure management on the shield aircraft side is required.

(Means for Solving the Problems) The present invention attempts to solve these problems, and includes a cutter drum and a fixing part on the shield main body side, which face each other across the muddying material supply path. Interposed with an inner diameter muddying seal and an outer diameter mudding seal,
The allowable sealing pressure of the muddying material of the muddying seal on the inner diameter side is made higher than the permissible sealing pressure of the muddying material of the mudding material on the outside diameter side, and the mudding pipe on the shield body side communicating with the muddying pipe on the cutter side. A safety valve is interposed in the mud adding pipe connecting the mud adding pump, and the safety valve is set to a pressure value lower than the allowable seal pressure of the mud adding material of the mud adding seal on the outer diameter side. The purpose of this is to create a muddy material for a highly reliable muddy shield that controls the muddying material injection pressure and prevents dirt from entering the important cutter drive and bearing parts even in the worst case scenario. The point is to provide an injection device.

(Function) As described above, in the present invention, a cutter drum on the rotating side of the mud-adding type shield and the fixed part on the shield body side are interposed so as to face each other across the mud-adding material supply path. Of both the inner and outer muddy seals, the allowable sealing pressure for the muddying material of the muddying seal on the inner diameter side, which is closer to the bearing part and drive part of the cutter, is the allowable sealing pressure of the muddying material of the mudding material on the outer diameter side. Since the pressure was set higher than the pressure, when the pressure of the muddy material in the muddying material supply path increases, the muddying seal on the outer diameter side is first broken and the muddy material escapes to the face side. This prevents muddying material from entering the cutter drive section and bearing section, which are important parts of the shield machine.

In addition, in the present invention, a pressure value lower than the allowable seal pressure of the mud adding seal material on the outer diameter side is set in the mud adding pipe connecting the mud adding pipe on the side of the shield body and the mud adding pump. Since the safety valve is provided, muddying material with a pressure higher than the set value will not be supplied to the muddying pipe due to a failure or a mistake in the muddying material supply device.

(Example) The present invention will be described below with reference to the illustrated embodiments.

1 is a shield body, 2 is a cutter, and 3 is a cutter bearing. A cutter drum 4 is fixed to the rotating part on the outer diameter side of the bearing 3, and is attached to the shield body 1 to a gear part provided on the outer periphery of the same part. A small gear 6 fixed to the drive shaft of the cutter drive motor 5 meshes with the cutter drive motor 5, and the cutter 2 is driven and rotated by operating the motor 5.

7 is a dirt seal interposed between the cutter drum 4 and the shield body 1.

Reference numeral 8 denotes one or more mud adding pipes penetrated through the cutter 2 so that the tip communicates with the face side, and a mud adding pipe penetrated through the shield body 1, both mud adding pipes 8 and 9.
Opposed ends of the shield body 1 communicate with an internal space between an inner mud adding seal 10 and an outer mud adding seal 11 which are interposed between the cutter drum 4 and the shield body 1. Therefore, the allowable seal pressure of the mud adding material of the mud adding seal 10 on the inner diameter side is configured to be higher than the allowable sealing pressure of the mud adding material of the mud adding seal 11 on the outer diameter side.

The rear end of the mud adding pipe 9 on the side of the shield body 1 is connected to a valve 12, and a mud adding pipe 13 is connected between the valve 12 and a mud adding pump (not shown). A safety valve 14 is provided which is set to a pressure lower than the allowable sealing pressure of the mud adding material of the mud adding seal 11 on the outer diameter side.

In the figure, 15 is an earth and sand seal, and 16 is a screw conveyor for soil removal.

Since the illustrated embodiment is constructed as described above, malfunctions or mistakes in the muddying material supply equipment may result in
When a muddying material with a pressure higher than the permissible sealing pressure of the muddying material of the outer diameter side muddying seal 11 is supplied, the safety valve 14 applies pressure to the seal portion formed by the inner diameter side and outer diameter side dead seals 10 and 11. Mud material with a pressure higher than the allowable seal pressure of the seal is not pumped. Further, even if the pressure of the muddying material in the muddying pipes 8 and 9 rises, the seal of the mudding seal 10 on the outer diameter side is broken first, and the mudding material escapes to the face side, thereby preventing the shielding machine. Earth and sand will not enter the cutter drive part and bearing part, which are important parts of the cutter.

(Effect of the invention) As described above, in the present invention, both the inner and outer muddy seals are interposed between the cutter drum and the shield body so as to face each other across the muddying material supply path. Inside, the allowable sealing pressure of the muddying material of the inner diameter side seal is set to be higher than that of the mudding material of the outer diameter side mudding seal, and it communicates with the muddying pipe on the shield body side and is connected to the muddying pump. A safety valve set to a pressure lower than the permissible sealing pressure of the muddy material of the outer diameter side seal is installed in the muddy pipe, so that even in the worst case, the muddy material can escape to the face side. In order to prevent backflow to the cutter drive unit side, a safety valve is installed in the mud addition pipe connected to the mud addition pipe on the shield body side, which is set to a pressure lower than the allowable seal pressure of the mud addition seal on the outer diameter side. Therefore, it is possible to prevent the mud adding material having a pressure higher than the allowable sealing pressure of the mud adding seal from being supplied to the shield machine, thereby further increasing safety.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a mud-adding shield equipped with an embodiment of the mud-adding material injection device for the mud-adding shield according to the present invention, and FIG. 2 is an enlarged view of the main part of FIG. 1. DESCRIPTION OF SYMBOLS 1...Shield body, 2...Katsuta, 3...Katsuta bearing part, 4...Katsuta drum, 5...Katsuta drive motor, 8...Mud adding pipe, 9...Mud adding pipe, 10
... Inner diameter side mud adding seal, 11... Outer diameter side mud adding seal, 13... Mud adding pipe, 14... Safety valve.

Claims (1)

[Scope of utility model registration request] In a muddy type shield in which mudding material is injected into the front surface of a cutter through a muddying pipe that passes through the cutter, the cutter drum and a fixed part on the shield body side face each other across the muddying material supply path. An inner diameter side mud adding seal and an outer diameter side mud adding seal are interposed, and the mud adding material allowable seal pressure of the inner diameter side mud adding seal is made higher than the mud adding material allowable seal pressure of the outer diameter side mud adding seal, and the In the muddying pipe connecting the muddying pump and the muddying pipe on the shield body side which communicates with the muddying pipe on the cutter side, a pressure value lower than the permissible sealing pressure of the muddying material of the mudding seal on the outer diameter side is applied. A muddy material injection device for a muddy type shield, characterized by being equipped with a set safety valve.