JPS6145277Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an earth pressure type shield excavator, and particularly to an earth pressure type shield excavator that can be used by excavators to cut and stir the excavator.

Conventional earth pressure type shield excavators are applicable to a narrow range of soil types.For example, in non-flowable soils such as sand layers, the inside of the pressure chamber and screw conveyor are blocked by the excavator, making it difficult to remove soil. It was hot.

For this purpose, a lubricant is injected into the pressure chamber, and a plurality of stirring blades installed inside the cutter agitate the earth and sand in the pressure chamber, converting the excavated soil into fluid soil and discharging it.

In this type of earth pressure shield excavator, the rotation speed of the stirring blade is the same as that of the cutter drive shaft, and even if the rotation speed is increased to improve the stirring effect, the cutter will not work properly due to the relationship between the appropriate rotation speed and torque for excavating the ground. This is not possible since the rotation of the drive shaft is fixed at a constant low value. Mixing and stirring at such low rotation speeds has a weak stirring effect and it is difficult to expect a change in soil texture to become more uniform.

The earth pressure type shield excavator of the present invention is designed to eliminate the above-mentioned drawbacks, and is equipped with a mechanism for pulling the radially extending cutter into the pressure chamber in the axial direction, and removes the earth and sand taken into the pressure chamber. It is characterized by being able to cut and agitate finely by the cutter itself.

Embodiments of the present invention will be described below with reference to the drawings.

In the figure, 1 is a large number of cutter bits, 2 is a rod-shaped cutter extending radially with the cutter bit 1 provided on the front side, 3 is a cutter drive shaft, 4 is a bearing for the cutter drive shaft 3, 5 is a cutter extension/retraction device using a hydraulic jack, 6 is a cutter rotation drive hydraulic motor, 7 is a shield jack, 8 is a screw conveyor, 9 is a screw rotation drive hydraulic motor, 11 is a pressure chamber formed at the rear of the cutter 2, 13 is a shield skin plate,
Reference numeral 15 indicates an earth pressure gauge, and in the present invention, the cutter 2 and the cutter drive shaft 3 are made movable in the axial direction by a cutter expansion/contraction device 5, so that the cutter 2 can be retracted into the middle part of the pressure chamber 11. At the same time, the rotation speed and rotation direction of the cutter drive shaft 3 can be changed using a speed reduction mechanism (not shown).

In another embodiment of the present invention, a hollow hole 12 is provided that passes through the cutter drive shaft 3 and the cutter 2, and communicates with a spout 10 formed on the outer surface of the cutter 2, so that the lubricant can be spouted from the spout 10. do.

In yet another embodiment of the invention, a water inlet pipe 14 is provided which opens into the pressure chamber 11.

Note that 16 indicates a segment.

Since the earth pressure type shield excavator of the present invention has the above-described configuration, during excavation, the cutter 2 is rotated by the hydraulic motor 6 while the cutter drive shaft 3 is extended by the cutter extension device 5 as shown in FIG. Select the rotation speed of the cutter 2 that is appropriate for the soil type. Further, at the same time as the rotation, lubricant is ejected from the cutter drive shaft 3 and the hollow hole 12 in the cutter 2 from the ejection port 10 on the front surface of the cutter 2.

After the predetermined digging is completed, the cutter 2 is pulled into the pressure chamber 11 by the cutter expansion/contraction device 5 while being rotated at a rotation speed appropriate for chopping and agitating the cutter 2, and the pressure chamber 11 is moved in the axial direction as necessary. The cutter 2 itself cuts and stirs the mixed earth and sand with the lubricant taken into the cutter 2 itself.

After the shredding and stirring is completed, the direction of rotation of the cutter 2 is changed and the cutter 2 is extended to the position for excavating the earth and sand while continuing the shredding and stirring.

If the inside of the pressure chamber 11 is clogged with earth and sand, water is injected through the water injection pipe 14 to relieve the blockage.

At the same time as the excavation process, the screw conveyor 8 is rotated by the hydraulic motor 9 to perform an earth removal process, but this earth removal process is stopped during the shredding and stirring process. In this earth removal step, earth pressure gauge 15 is monitored and earth is removed while maintaining a predetermined earth pressure.

By repeating the above steps, the earth and sand in the pressure chamber 11 can be reliably fluidized and transformed into watertight soil. Therefore, the sensing error of the earth pressure gauge 15 is eliminated, the ground range to which the earth pressure type shield excavator can be applied can be expanded, and the stability of the face can be measured.

[Brief explanation of the drawing]

FIG. 1 is an explanatory sectional view of the earth pressure type shield excavator of the present invention, and FIG. 2 is a side view thereof. 1... cutter bit, 2... cutter, 3...
... Cutter drive shaft, 4 ... Bearing, 5 ... Cutter expansion and contraction device, 6 ... Cutter rotation drive hydraulic motor, 7 ... Shield jack, 8 ... Screw conveyor, 9 ... Screw rotation drive hydraulic motor, 10 ... Spout port, 11 ... Pressure chamber, 12 ... Hollow hole, 13 ... Shield skin plate, 14 ... Water injection pipe, 15 ... Earth pressure gauge, 16
……segment.

Claims (1)

[Scope of utility model registration request] An earth pressure type shield excavator characterized by being equipped with a mechanism for drawing a radially extending cutter into a pressure chamber in the axial direction, so that the earth and sand taken into the pressure chamber can be chopped and stirred by the cutter itself. .