JP7069450B2 - Digger and its operation method - Google Patents

Description

The present invention relates to a digging machine, and more particularly to a digging machine provided with a copy cutter.

Conventionally, various excavators (including propulsion machines, in the present specification) such as earth pressure type shield excavator, mud pressure type shield excavator, muddy water type shield excavator, earth pressure type propulsion machine, mud concentration type propulsion machine, muddy water type propulsion machine, etc. , Simply referred to as a "digger") is provided with a copy cutter (hereinafter, may be referred to as a "conventional copy cutter" in the present specification) for performing curve construction and meandering correction. (See, for example, Patent Document 1.).
This conventional copy cutter is built into the cutter head and consists of a telescopic cylinder and a bit that can protrude to the outer peripheral side of the cutter head. By digging the outer peripheral side of the cutter head arbitrarily, curve construction and meandering correction I am trying to be able to do.

It has also been proposed to control excavation by equipping the chamber behind the cutter head with a sensor for measuring the strength of the ground (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 11-81877 Japanese Unexamined Patent Publication No. 2017-96049

By the way, in the above-mentioned conventional excavator, since the copy cutter is composed of a telescopic cylinder and a bit that can project to the outer peripheral side of the cutter head, it exerts an excavating action on the ground located on the outer peripheral side of the cutter head. However, this is to perform partial over-digging necessary for curve construction and meandering correction, and if over-digging is performed over the entire circumference, it will hinder the direction control of the excavator. Not usually done.

The present invention provides an excavator equipped with a copy cutter capable of exerting an excavation action on a ground located on the front side of a cutter head, which was not possible with the copy cutter provided in the conventional excavator, and an operation method thereof. The purpose is to do.

In order to achieve the above object, the excavator of the present invention is an excavator having a cutter head at the tip and a chamber at the rear of the cutter head, on the support arm of the cutter head from the front surface to the front of the cutter head. It is characterized by being equipped with a copy cutter composed of a telescopic cylinder that can be projected and a bit.

In this case, a cutter torque detecting mechanism for detecting the cutter torque of the cutter head for each rotation angle can be provided.

Further, in the method of operating the excavator of the present invention, in the method of operating the excavator having the cutter head at the tip and the chamber at the rear of the cutter head, the front surface of the cutter head provided on the support arm of the cutter head. By rotating the cutter head with the copy cutter consisting of a telescopic cylinder and a bit that can protrude forward from the top, the entire circumference of the ground in front of the cutter head is cut, and the cutter torque of the cutter head is rotated. It is characterized in that the strength of the ground on the front surface of the cutter head is grasped by the measured value of the cutter torque measured by the cutter torque detection mechanism detected every time.

In this case, the strength of the ground in front of the cutter head can be grasped, and when the ground has a hardness distribution, the hard portion can be partially pre-drilled by the copy cutter.

According to the excavator of the present invention, in an excavator having a cutter head at the tip and a chamber at the rear of the cutter head, a telescopic cylinder capable of projecting forward from the front surface of the cutter head to the support arm of the cutter head. By providing a copy cutter composed of a bit and a bit, the copy cutter can exert an excavation action on the ground located on the front side of the cutter head over the entire circumference of the cutter head.

Further, excavation can be controlled by providing a cutter torque detecting mechanism for detecting the cutter torque of the cutter head for each rotation angle.

Further, according to the operation method of the excavator of the present invention, in the operation method of the excavator having the cutter head at the tip and the chamber at the rear of the cutter head, the cutter head provided on the support arm of the cutter head. By rotating the cutter head with the copy cutter consisting of a telescopic cylinder and a bit that can protrude forward from the front of the cutter head, the entire circumference of the ground on the front of the cutter head is cut, and the cutter torque of the cutter head is reduced. The strength of the ground on the front of the cutter head can be grasped from the measured value of the cutter torque measured by the cutter torque detection mechanism detected for each rotation angle, and it is based on the strength of the ground on the front of the cutter head that has been grasped. Excavation control, specifically, adjustment control of the protrusion amount of the copy cutter protruding forward from the front surface of the cutter head can be performed.

In this case, the strength of the ground in front of the cutter head can be grasped, and if the ground has a hardness distribution, the hard part can be partially pre-drilled by the copy cutter, and the core is removed. By the effect, the hardness of the hard part can be lowered, the hardness and softness of the face ground can be averaged, and the excavation accuracy by the cutter head, especially the straightness of the excavator can be improved.

An explanatory view showing an embodiment of the excavator of the present invention, (a) is a cross-sectional view, (b) is a front view, and (c) is an enlarged cross-sectional view of part A of (a) and (b). be. It is explanatory drawing which shows an example of the excavation control of the excavator of this invention.

Hereinafter, embodiments of the excavator of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the excavator of the present invention.
This excavator is a muddy soil pressure type shield excavator having a cutter head 1 at the tip and a chamber 2 at the rear of the cutter head 1, and excavates a face which is an excavation surface of the ground in front of the cutter head 1. The excavated earth and sand are taken into the chamber 2, and the mud material injected from the mud material discharge ports 3a and 3b provided in the center portion of the cutter head 1 and the spoke 16 respectively is arranged in the cutter head 1 and the chamber 2. By stirring and mixing with a stirring blade (not shown), the excavated soil is converted into mud having plastic fluidity and impermeableness, and this mud is converted into a soil removal device including a screw conveyor 4 extending rearward from the inside of the chamber 2. While maintaining this state, the mud pressure in the chamber 2 is generated by the thrust of the shield jack 5, and the soil pressure of this earth and sand acts on the face to counteract the soil pressure and ground water pressure of the face. Then, the face is stabilized, and the excavator is trying to excavate the ground while balancing the amount of propulsion and the amount of soil discharged.

The front torso 61 and the rear torso 62, which form the shield fuselage 6 and include the chamber 2, are connected by a direction correction jack 7.

An earth pressure gauge 8 for detecting the earth pressure (pressure) generated in the chamber 2 is arranged in the chamber 2.

A cutter head 1 is rotatably supported on the front body 61 via a support bearing at the tip thereof, and is rotationally driven by a drive motor 9.

A conventional copy cutter 10 composed of a telescopic cylinder equipped with a cylinder and a bit is built in the outer peripheral portion of the cutter head 1, and can be projected to the outer peripheral side of the cutter head 1, and the outer peripheral side of the cutter head 1 can be arbitrarily set. By digging in excess, it is possible to perform curve construction and meandering correction.

A cutter bit 11, a leading bit 12, and a gauge bit 13 are attached to the front surface of the cutter head 1.

Further, a copy cutter 15 composed of a telescopic cylinder and a bit so that the support arm 14 of the cutter head 1 can project forward from the front surface of the cutter head 1 (hereinafter, “forward telescopic copy cutter” in the present specification”. In some cases.)
The forward telescopic copy cutter 15 is arranged on the outer peripheral portion of the front surface portion of the cutter head 1 and has a protrusion angle θ of 0 to 45 ° with respect to the horizontal axis (about 30 ° in this embodiment). Although the maximum protrusion dimension L is 30 to 200 mm, it can be set to an appropriate size and protrusion amount according to the outer diameter of the excavator, the soil quality, and the like.
Then, the forward telescopic copy cutter 15 can exert an excavation action on the ground located on the front side of the cutter head 1 on the entire circumference of the cutter head 1.
Here, in this embodiment, since the support arm 14 of the cutter head 1 supports the outer peripheral portion of the cutter head 1, the copy cutter 15 is arranged on the outer peripheral portion of the front surface portion of the cutter head 1. However, in the case of a method of supporting the middle portion of the cutter head 1 (inside the outer peripheral portion), the copy cutter 15 is placed in the middle portion of the front surface portion of the cutter head 1 where the support arm 14 is located. It is arranged so as to be able to project forward from the front surface of 1.

The excavator is provided with a cutter torque detection mechanism that detects the cutter torque of the cutter head 1 for each rotation angle, and uses this to control excavation.
Specifically, by rotating the cutter head 1 with the front telescopic copy cutter 15 protruding, the entire circumference of the ground in front of the cutter head 1 is cut (at this time, so-called rolling does not occur). (Adjusts the protruding state of the copy cutter 15), the measured value of the cutter torque of the cutter head 1 measured by the cutter torque detection mechanism (hydraulic value when the drive system is a hydraulic motor drive system, and hydraulic value when the drive system is an electric motor drive system). The strength of the ground in front of the cutter head 1 is grasped by the current value), and the excavation control based on the strength of the ground in front of the grasped cutter head 1, more specifically, from the front of the cutter head 1. It is possible to control the adjustment of the protrusion amount of the copy cutter 15 that protrudes forward.
That is, as shown in FIG. 2A, the copy cutter 15 is extended and penetrated into the ground, then the cutter head 1 is rotated, and the fluctuation of the cutter torque (rotational torque) of the cutter head 1 is measured. If necessary, it is compared with the rotational torque when the copy cutter 15 is in the contracted state.
It is determined that the part with a relatively high rotational torque value has a high ground hardness, and the part with a low value has a low ground hardness (Fig. 2 (b)). Is displayed (FIG. 2 (c)).
When the hardness difference is large, as shown in FIG. 2D, the copy cutter 15 is extended only in the portion having high hardness as judged from the hardness / softness screen, and the ground is pre-cut in a groove shape.
In this way, by grasping the strength of the ground on the front surface of the cutter head 1 and partially pre-excavating the hard part with the copy cutter 15 when the ground has a hardness distribution, the core By the pulling effect, the hardness of the hard portion can be lowered, the hardness and softness of the face ground can be averaged, and the excavation accuracy by the cutter head 1, particularly the straightness of the excavator can be improved.

FIG. 2 (e) is a diagram of a monitor showing the experimental results (the numbers are the measured values (unit: MPa (hydraulic pressure)) of the cutter torque (rotational torque) of the cutter head 1 during excavation).
As is clear from the experimental results in FIG. 2 (e), the forward telescopic copy cutter 15 is extended and penetrated into the ground, and then the cutter head 1 is rotated to obtain the cutter torque (rotation torque) of the cutter head 1. As a result of measuring the fluctuation of, the value of the rotational torque was high in the portion where the ground hardness was high, and the value of the rotational torque was low in the portion where the ground hardness was low (pressure difference: 3.3 MPa).
The fluctuation pressure difference of the rotational torque when the copy cutter 15 was contracted at this time was 0.3 MPa.

The excavator of the present invention has been described above based on the embodiment thereof, but the present invention is not limited to the configuration described in the above embodiment, and the configuration is appropriately changed as long as the purpose is not deviated. It is something that can be done.

The excavator of the present invention and its operation method are provided with a forward telescopic copy cutter on the ground located on the front side of the cutter head, which was not possible with the conventional copy cutter provided in the conventional excavator. Since it has the property of being able to exert an excavation action, it is a soil pressure type shield excavator, a mud pressure type shield excavator, a muddy water type shield excavator, an earth pressure type propulsion machine, a mud concentration type propulsion machine, and a muddy water type propulsion machine. It can be suitably used for various digging machines such as.

1 Cutter head 2 Chamber 3a Mud material discharge port (center part)
3b Mud material discharge port (spoke)
4 Screw conveyor 5 Shield jack 6 Shield body 61 Front body 62 Rear body 7 Direction correction jack 8 Earth pressure gauge 9 Drive motor 10 Copy cutter (conventional copy cutter)
11 Cutter bit 12 Leading bit 13 Gauge bit 14 Support arm 15 Copy cutter (forward telescopic copy cutter)
16 spokes

Claims (3)

In an excavator having a cutter head at the tip and a chamber at the rear of the cutter head, a copy cutter composed of a telescopic cylinder and a bit that can project forward from the front of the cutter head on the support arm of the cutter head . An excavator characterized by being provided with a cutter torque detection mechanism that detects the cutter torque of the cutter head for each rotation angle . In the operation method of an excavator having a cutter head at the tip and a chamber at the rear of the cutter head, it is composed of a telescopic cylinder and a bit provided on the support arm of the cutter head and can be projected forward from the front surface of the cutter head. A cutter measured by a cutter torque detection mechanism that cuts the entire circumference of the ground in front of the cutter head by rotating the cutter head with the made copy cutter protruding, and detects the cutter torque of the cutter head for each rotation angle. A method of operating an excavator, which is characterized in that the strength of the ground in front of the cutter head is grasped from the measured value of torque. In the method of operating the excavator according to claim 2 , the strength of the ground in front of the cutter head is grasped, and when the ground has a hardness distribution, the hard part is partially pre-drilled by a copy cutter. How to operate the excavator, which is characterized by that.

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