JPS6139030Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a shield excavator, and its purpose is to create a shield excavator that can prevent the kneading effect of the excavated soil taken into the pressure chamber from decreasing when the excavation diameter is large. It provides an opportunity for

That is, the present invention provides a rotary drive system in which a ribbon-shaped screw blade for mixing excavated soil is rotatably provided in a pressure chamber formed in a cutter head, and the ribbon-shaped screw blade is rotationally driven via an annular body fixed to its outer periphery. A screw conveyor-type soil removal device for discharging excavated earth and sand in the pressure chamber into an atmospheric pressure chamber is provided with a screw blade tip portion located inside the ribbon-shaped screw blade.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. 1 is a shield main body, 2 is a rotary drive device 3 provided at the front of the shield main body 1;
4 is a pressure chamber formed within the cutter head 2, which is rotatable. Reference numeral 5 denotes a ribbon-shaped screw blade for mixing excavated soil that is rotatably provided in the pressure chamber 4, the front end of which is supported by the front part of the cutter head 2 via a bearing 6, and the rear end is fixed to its outer periphery. The cutter head 2 is supported at the rear of the cutter head 2 via an annular body 7 and a bearing 8 provided on the outer periphery of the annular body 7. The ribbon-shaped screw blade 5 is rotationally driven via the annular body 7. That is, an internal gear 9 is attached to the inside of the rear end of the annular body 7, and a pinion 11 attached to the output shaft of the rotary drive device 10 is meshed with the internal gear 9. Reference numeral 12 denotes a screw conveyor type soil removal device for discharging excavated soil in the pressure chamber 4 into the atmospheric pressure chamber 13, and the screw blade 1 for soil discharge is
4 is formed in a ribbon shape and extends from the cylindrical casing 15 to the inside of the pressure chamber 4 so that its tip is located inside the ribbon-like screw blade 5 for mixing the excavated earth and sand. The soil removal screw blade 14 is rotationally driven via an annular body 16 fixed to its rear outer periphery, similarly to the ribbon-shaped screw blade 5 for excavated earth and sand kneading. That is,
An external gear 17 is attached to the outer periphery of the annular body 16, and a pinion 19 attached to the output shaft of a rotary drive device 18 is meshed with the external gear 17. 20 is a gate for discharging excavated soil provided at the rear end of the cylindrical casing 15, and 21 is a conveyor for discharging excavated soil provided below the gate 20.
In addition, 22 is a slurry (special paste) inside the pressure chamber 4.
This is an injection tube for injecting.

Therefore, according to the above configuration, the excavated soil taken into the pressure chamber 4 is efficiently kneaded with slurry by the ribbon-shaped screw blades 5 for mixing, and the screw blades 14 of the earth removal device 12 mix the excavated earth and sand into the cylindrical casing 15. The excavated soil is sent to the rear, where a sand plug capable of resisting groundwater pressure and collapse earth pressure is formed, and the gate 20 is opened and the excavated soil is discharged onto the carry-out conveyor 21. In this way, since the ribbon-shaped screw blades 5 are used to mix the excavated soil and slurry, it is possible to mix them efficiently even when coarse gravel is included, and it also has the effect of feeding the soil to the earth removal device. It is done efficiently. Further, since the ribbon-shaped screw blade 5 is configured in a continuous spiral, it has low kneading resistance and is resistant to wear.

In the above embodiment, the screw blade 14 of the earth removal device 12 is configured in a ribbon shape capable of discharging gravel approximately 2/3 of the outer diameter of the blade. But that's fine.
Further, in FIG. 1, the cutter head 2 is constructed so that the cutter surface is vertical, but the present invention can also be applied to a structure in which the cutter surface is inclined.

As described above, according to the shield excavator of the present invention, the excavated soil taken into the pressure chamber is efficiently mixed with slurry by the ribbon-shaped screw blades,
Especially when the excavation diameter is large, it has a kneading effect,
Furthermore, since the screw blade of the earth removing device is located within the pressure chamber, the excavated earth and sand in the pressure chamber can be efficiently sent to the earth removing device.

[Brief explanation of drawings]

FIG. 1 is an overall vertical sectional view of an embodiment of the present invention, and FIG. 2 is a sectional view taken along the - arrow in FIG. DESCRIPTION OF SYMBOLS 1...Shield body, 2...Cut head, 4...Pressure chamber, 5...Ribbon-shaped screw blade, 7...Annular body, 12...Earth removal device, 13...Atmospheric pressure chamber, 14...Screw blade.

Claims (1)

[Scope of utility model registration request] A ribbon-shaped screw blade for mixing excavated earth and sand is rotatably provided in a pressure chamber formed in the cutter head, and a rotation drive device is provided for rotationally driving the ribbon-shaped screw blade through an annular body fixed to its outer periphery. A shield excavator characterized in that the tip of a screw blade of a screw conveyor-type earth removal device for discharging excavated earth and sand in a pressure chamber into an atmospheric pressure chamber is located inside the ribbon-shaped screw blade.