JPH11173055A - Excavation control method for casing driver, excavation controller, and self-settling load measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control technique to prevent a casing pipe from running away by reducing energy loss at a relief valve for pressure regulation at the cylinder side of a thrust cylinder. SOLUTION: When excavating ground with a casing pipe 10 by using a casing driver equipped with a pilot-operation type relief valve 32 capable of regulating the pressure at the cylinder side of a thrust cylinder 6, in order to prevent it from running away, the thrust bearing 6 is extended to a degree of leaving a stroke capable of extending a height portion of a cutter bit 26 and the casing pipe 10 is held with a casing grasping band 9, and the casing pipe 10 is raised by a cutter bit height with a thrust cylinder 6 and is rotated by a hydraulic motor 12. Under this condition, a self settling load obtained by measuring a pressure at the cylinder side and a pressure at the rod side of the thrust cylinder 6 is set to the setting pressure of the relief valve 32 by the pressure at the cylinder side in such a manner that a supporting force supporting the lifting frame 5 at the cylinder side will not be lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gripping means for gripping a casing pipe, a thrust cylinder capable of supporting and lowering the gripping means, a motor for rotating the gripping means, and a pressure on the cylinder side of the thrust cylinder. TECHNICAL FIELD The present invention relates to an excavation control method, an excavation control device, and a self-sinking load measurement method for a casing driver having an adjustable relief valve.

[0002]

2. Description of the Related Art A casing driver is generally known as a device for press-fitting and pulling out a casing pipe such as a large-diameter steel pipe pile or a steel pipe used for civil engineering and construction work. Some casing pipes have a cutter bit attached to the tip. When press-fitting such a casing pipe with a casing driver,
The casing pipe is gripped by a casing driver and pushed while rotating to excavate the ground. The present invention improves the excavation control when excavating the ground in the casing pipe press-fitting process and a technique useful for the control,
Or to create. 8 to 10 show examples of a casing driver that has been generally used in the related art, and the technical contents thereof will be outlined based on these drawings. 8 is a plan view showing an example of a casing driver generally used conventionally, FIG. 9 is a right side view of FIG. 8, and FIG. 10 is a front view of FIG.

In FIGS. 8 to 10, reference numeral 1 denotes a female joint 2;
0 and a male fitting 24 which is detachably attached to the fitting and attached thereto, 2 is the casing driver described above, and 3 is a casing driver that supports the casing driver 2 when it is installed on the ground. A jack for leveling to adjust the posture horizontally, and a casing pipe 1 at the center
0, a substantially square frame base frame 4a, 4b, 4c,
Reference numeral 4d denotes a vertical guide frame erected at the four corners of the base frame 4, and 5 denotes a frame having a casing pipe 10 insertion space at the center, and each of the vertical guide frames 4a, 4b,
An elevating frame that is guided so as to be able to move up and down by 4c and 4d, 6
Is a thrust cylinder that drives the lifting frame 5 to move up and down. Reference numeral 8 denotes a ring-shaped elevating frame 6 having a casing pipe 10 insertion space.
A rotating body 9 rotatably mounted via a bearing (not shown), 9 is a casing gripping band as gripping means for gripping the casing pipe 10, 10 is the casing pipe described above, and 11 is a casing gripping band 9. A hydraulic band cylinder 12 which is a component of the casing gripping band 9 for gripping the casing pipe 10 and releasing the gripping is provided at a lower portion of the elevating frame 5, and is provided with a casing via the rotating body 8. This is a hydraulic motor that rotationally drives the gripping band 9.

[0004] Vertical guide frames 4a, 4b, 4c, 4d
Has two guide surfaces a and b, respectively, and guides the elevating frame 5 with these two guide surfaces a and b. Of these guide surfaces a and b, the guide surface a is a surface that receives a rotational reaction force generated when the casing gripping band 9 is rotationally driven to rotate the casing pipe 10, They are arranged substantially perpendicular to the tangential direction. The guide surface b is a surface that functions to stably support the horizontal movement of the elevating frame 5 and is arranged in parallel with the tangential direction of the rotating circle of the rotating body 8. Two sliding surfaces are formed on the lifting frame 5 so as to face these guide surfaces a and b, respectively.
The thrust cylinder 6 has vertical guide frames 4a, 4b,
Similarly to 4c and 4d, the cylinder unit is mounted on the base frame 4 at the four corners of the base frame 4, and the cylinder unit is mounted on the base frame 4 and the rod unit is mounted on the elevating frame 5, but may be mounted in reverse. Vertical guide frames 4a, 4b,
4c, 4d and the four thrust cylinders 6
In FIG. 8, the vertically adjacent ones and the right and left adjacent ones are arranged so as to be symmetrical with respect to the left and right radial lines and the upper and lower radial lines of the rotating body 8, respectively.

An external gear is formed on the outer periphery of the rotating body 8 and meshes with a pinion (not shown in FIG. 1 for reference) which is driven to rotate by a hydraulic motor 12. Thus, the rotation of the hydraulic motor 12 is transmitted at a reduced speed. The hydraulic motors 12 are arranged on the left and right of the lifting frame 5 in this example. The casing gripping band 9 is attached to an upper portion of the rotating body 8 and is driven to rotate by a hydraulic motor 12 via the rotating body 8. Since the casing driver 2 has the above-described structure, when the thrust cylinder 6 is expanded and contracted, the elevating frame 5 is moved to the vertical guide frames 4a, 4a.
The casing 9 is moved up and down while being guided by the guide surfaces a and b of the b, 4c and 4d. As a result, the casing gripping band 9 can be moved up and down together with the hydraulic motor 12 and the rotating body 8. Also, by driving the hydraulic motor 12,
The casing gripping band 9 can be rotationally driven at a reduced speed via a gear transmission mechanism including a pinion and a rotating body 8.

Next, the structure of the casing gripping band 9 will be described. The casing gripping band 9 includes a fixed band 9a having a substantially semicircular arc shape, and pivot shafts 14 and 15 having one ends attached to both ends of the fixed band 9a.
A pair of substantially arc-shaped movable bands 9 pivotably connected with each other.
b and 9c, and a band cylinder 11 connected to the other end of each of the pair of movable bands 9b and 9c by pins 16 and 17, and is formed in a substantially ring shape so as to form a casing pipe insertion space at the center. Is formed. Fixed band 9a
The inner surface is formed in the same arc shape as the outer surface of the casing pipe 10 and is attached to the rotating body 8. The movable bands 9b, 9c can be rotated around the pivot shafts 14, 15 by operating the band cylinder 11. When the casing pipe 10 is to be gripped by the casing gripping band 9, the movable band 9
b, 9c with the band cylinder 11 to the casing pipe 10
By rotating the casing pipe 10 to the side, the casing pipe 10 is pressed against the arcuate inner surface of the fixed band 9a by the movable bands 9b and 9c, and is gripped while being positioned.

Reference numerals 18 and 19 denote band cylinders 1 respectively.
1 is a hydraulic pipe communicating with the cylinder side (bottom side) and the rod side. Three female joints 20 are disposed on these hydraulic pipes 18 and 19 at intervals of approximately 120 degrees, respectively. The male joint 24 is provided in each of two pipelines that can be selectively connected to the oil supply pipe and the oil drain pipe by switching the switching valve. By connecting, the pressure oil can be supplied to the cylinder side and the rod side of the band cylinder 11, and the supplied pressure oil can be discharged. Since the joint attaching / detaching device 1 including the female joint 20 and the male joint 24 is not directly related to the present invention, a detailed description thereof will be omitted.

When the casing pipe 10 is to be press-fitted by the casing driver 2 having the above structure, the following steps are performed.

1. The thrust cylinder 6 is extended to the limit to raise the lifting frame 5 and the band cylinder 1
After extending the casing pipe 1 so as to expand the casing pipe insertion space, at the beginning of the press-fitting, the casing pipe 10 having the cutter bit is inserted into the same. 2. The band cylinder 11 is contracted, and the casing pipe 10 is gripped by the casing gripping band 9. 3. The casing gripping band 9 is driven by the hydraulic motor 12.
Of the casing pipe 10
To rotate. 4. While the casing pipe 10 is gripped by the casing gripping band 9 and rotated in this manner, the thrust cylinder 6 is contracted and the elevating frame 5 is lowered, thereby pushing the casing pipe 10 to excavate the ground,
Press the casing pipe 10 in. 5. When the thrust cylinder 6 shrinks to the limit, the rotational drive of the casing gripping band 9 and the drive of the thrust cylinder 6 by the hydraulic motor 12 are stopped. 6. The band cylinder 11 is extended to release the gripping of the casing pipe 10 by the casing gripping band 9. 7. In a state where the gripping of the casing pipe 10 is released, the thrust cylinder 6 is extended to the limit again and the lifting frame 5 is raised. 8. If necessary, add a new casing pipe 10 having no cutter bit to the press-fitted casing pipe 10.
Is added. 9. The above steps 2 to 8 are repeated to press-fit the casing pipe 10 of a predetermined length. The casing pipe 10 can be pulled out by the casing driver 2, but the description is omitted. By the way, the thrust cylinder 6 includes the lifting frame 5
Various weights of the equipment of the casing driver 2 such as the rotating body 8, the casing gripping band 9, and the hydraulic motor 12 installed thereon act. Also, when the casing pipe 10 is gripped by the casing gripping band 9,
The weight of the casing pipe 10 also acts. Therefore, a force for contracting the thrust cylinder 6 inevitably acts on the thrust cylinder 6 even when the pushing force is not applied to the casing pipe 10 during the operation of the casing driver 2. Such a force acting on the thrust cylinder 6 is referred to as a self-sinking load in this specification. Casing pipe 10
When the ground is excavated while being pushed by rotating the casing pipe with a casing driver, the thrust cylinder 6 does not apply a supporting force for supporting the self-sinking load.
Escapes, and this self-sinking load causes the casing pipe 1
As a result, the excavation control when excavating the ground with the casing driver cannot be performed in a stable state. As a result, excavation of the ground by the casing driver may not be performed efficiently, or the cutter bit of the casing pipe 10 may be damaged.

As a technique for solving such a problem caused by a self-settling load during excavation control of the casing driver 2, a technique called a pushing force control method for a rotary tubing device has been conventionally proposed in Japanese Patent Publication No. Hei 7-15233. Have been. Therefore, the technology proposed in this publication will be described as a conventional technology, in which case, in order to clarify the correspondence with the present invention, terms used in this specification are used as much as possible, The terms used in this publication are added in parentheses after the terms used first. According to the technology proposed in this publication, when a self-setting load is applied during excavation with a casing driver (rotary tubing device), efficient excavation cannot be performed depending on the soil quality, or a cutter bit (excavation) for a casing pipe (casing tube) is not provided. And to improve the excavation control method of the casing driver based on the recognition that the casing bit may be damaged.

This excavation control method of a casing driver includes a rotating device as a gripping means for gripping a casing pipe, and a thrust cylinder (cylinder) capable of supporting and rotating the rotating device via a lifting frame (elevating device). ), A casing motor provided with a hydraulic motor that rotationally drives the rotating device and an electromagnetic proportional relief valve that can adjust the pressure on the cylinder side (cap-side cylinder chamber) of the thrust cylinder, and a casing pipe having a cutter bit at the tip. When excavating the ground, the control is performed so as to prevent the escape of the casing pipe. A relief valve for fixedly setting the pressure on the rod side (head side cylinder chamber) of the thrust cylinder so as to generate the maximum pushing force Fmax is provided.
When the set pressure R1 of the electromagnetic proportional relief valve is adjusted to the maximum set pressure, the pressure f1 on the rod side of the thrust cylinder that generates the maximum pushing force Fmax, the weight Wc of the casing pipe, the weight Wd of the rotating device and the lifting frame, and By adjusting the set pressure R1 of the proportional solenoid type relief valve,
The thrust cylinder can be expanded and contracted.

In the conventional casing driver excavation control method thus configured, when the set pressure R1 of the electromagnetic proportional relief valve is set to 0, the pushing force acting on the cutter bit of the casing pipe becomes f1 + Wc + Wd. When the maximum pushing force acts on the cutter bit, and when the set pressure R1 of the electromagnetic proportional relief valve is set to f1 + Wc + Wd, the pushing force acting on the cutter bit becomes zero. In the state where the pushing force acting on the cutter bit becomes zero, the cylinder side of the thrust cylinder 6 applies only the supporting force for supporting the self-sinking load together with the pressure against the rod side pressure of the thrust cylinder 6. In this state of the art, f1
+ Wc + Wd (pressure on the cylinder side of the thrust cylinder)
It can be said that −f1 (pressure on the rod side of the thrust cylinder), that is, Wc + Wd, is regarded as a load corresponding to the self-subsidence load.

[0013]

As described above, in the prior art, Wc + Wd is regarded as a load corresponding to a self-subsidence load. In this case, it does not accurately reflect the self-settling load acting on the thrust cylinder 6.
Therefore, this will be described with reference to FIG. FIG.
FIG. 4 is an explanatory diagram of a self-set load acting on a thrust cylinder during excavation by a casing driver. In FIG. 11, portions denoted by the same reference numerals as those in FIGS.
Represents the equivalent part. FIG. 11 schematically illustrates the casing driver already described with reference to FIGS. 8 to 10, and the pinion 1 not illustrated in these drawings.
3 also schematically shows that the rotating body 8 is rotated at a reduced speed by meshing the rotating body 8 with the external gear of the rotating body 8.

In FIG. 11, Wc is the weight of the casing pipe 10, Wr is the weight of the lifting frame 5, Wm
Is the weight of the rotating body 8 and the casing gripping band 9, and Wp is the self-sinking load acting on the thrust cylinder 6 when excavating the ground with the casing pipe 10. Self-sinking load Wp
Although other weights such as a stage installed on the elevating frame 5 also act on the weight acting as, the weight acting as the self-sinking load Wp is only the weight shown in FIG. Suppose that When the ground is excavated with the cutter bit 26 of the casing pipe 10, a kinetic friction force acts between the peripheral surface of the casing pipe 10 and the ground. The dynamic friction force Fm of the peripheral surface of the casing pipe 10 acts so as to reduce the weight acting as the self-settling load Wp. Then, the self-subsidence load Wp
Can be represented by the following Equation 1. Formula 1 Wp = (Wc + Wr + Wm) -Fm The weight Wd of the rotating device and the lifting frame referred to in the related art is considered to correspond to Wr + Wm in Formula 1.

As is clear from the analysis of the setting method of the set pressure R1 of the electromagnetic proportional relief valve in the prior art with reference to the equation (1), in the prior art, the ground is excavated with a casing pipe. The load Wc + Wd, which does not consider the dynamic frictional force Fm of the casing pipe peripheral surface that acts at all, and which is considered to correspond to the self-subsidence load by the conventional technology.
Does not accurately reflect the self-sinking load acting on the thrust cylinder when actually excavating and press-fitting the ground with a casing pipe. That is, when the ground is excavated with the casing pipe, the dynamic frictional force acts between the peripheral surface of the casing pipe and the ground, and the load Wc + Wd should be reduced. When the load is measured, such dynamic frictional force is not incorporated, and as a result, the self-sinking load is measured to be large.
As a result, when excavating the ground while controlling the electromagnetic proportional relief valve to prevent the escape of the casing pipe, the set pressure of the electromagnetic proportional relief valve for adjusting the cylinder side pressure of the thrust cylinder is: Therefore, the energy loss in the electromagnetic proportional relief valve increases.

The kinetic frictional force on the peripheral surface of the casing pipe increases gradually as a new casing pipe is added as the press-fitting of the casing pipe progresses. The energy loss in the relief valve is not negligible. For this reason, it is necessary to accurately measure the self-sinking load acting on the thrust cylinder when excavating the ground with the casing pipe according to Formula 1.
However, a method of actually measuring the dynamic friction force generated between the casing pipe peripheral surface and the ground when excavating with a casing pipe has not been established. It was technically difficult to measure.

The inventions of the present application have been made in view of such conventional technical situations, and a first technical problem of the invention of the present application is to provide a relief valve capable of adjusting the pressure on the cylinder side of a thrust cylinder. It is an object of the present invention to provide a casing driver excavation control technique that is used for a casing driver and that can reduce energy loss at a relief valve and prevent runaway of a casing pipe. A second technical problem of the invention of the present application is to provide a method of measuring a self-sinking load of a casing driver, which can accurately measure a self-sinking load acting on a thrust cylinder during excavation with a casing pipe.

[0018]

(A) Means for Solving the First Technical Problem The first technical problem is the first invention of this application according to claim 1 of the claims. The second invention of this application according to claim 2, the third invention of this application according to claim 3, the fourth invention of this application according to claim 4,
The fifth invention of this application according to claim 5, and claim 8
, Respectively, according to the sixth invention of the present application. As means for solving the technical problem, in the first invention of this application, the following 1) means, in the second invention of this application, the following 2) means, and in the third invention of this application, In the second invention, the following 3) means, the fourth of this application
The fourth invention employs the following 4) means, the fifth invention of this application employs the following 5) means, and the sixth invention of this application employs the following 6) means.

1) A gripping means for gripping the casing pipe, a thrust cylinder capable of supporting and lowering the gripping means, a motor for rotating the gripping means, and a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder. When excavating the ground with a casing pipe having a cutter bit at the tip using a casing driver provided with the casing driver, the cutter bit can be separated from the ground in a casing driver excavation control method that controls so as to prevent runaway of the casing pipe. A first step of extending the thrust cylinder so as to leave a stroke and gripping the casing pipe with the gripping means, and raising the casing pipe gripped by the gripping means by extending the thrust cylinder so as to separate the cutter bit from the ground. Drive motor with In the second step of further rotating the casing pipe, the pressure on the cylinder side of the cylinder side pressure and the rod side pressure of the thrust cylinder is measured while the casing pipe is raised and rotated, and based on the measurement result, And the third step of setting the set pressure of the relief valve so that the supporting force for supporting the gripping means does not fall below the thrust cylinder by the pressure on the cylinder side of the thrust cylinder. The ground was excavated by pushing with a thrust cylinder while rotating.

2) In the casing driver excavation control method for controlling the casing pipe to prevent runaway as in 1), the casing pipe gripped by the gripping means is extended with a thrust cylinder so as to separate the cutter bit from the ground. A first step of increasing the rotation of the thrust cylinder by rotating the casing pipe, and, in a state where the casing pipe is raised and rotated, reducing at least the cylinder-side pressure of the cylinder-side pressure and the rod-side pressure of the thrust cylinder. Measuring, the second step of setting the set pressure of the relief valve, so that the self-sinking load obtained based on the measurement result does not fall below the supporting force for supporting the gripping means by the pressure on the cylinder side of the thrust cylinder, After releasing the gripping of the casing pipe by the gripping means, After a third step of gripping the casing pipe by the gripping means extending the thrust cylinder to allow the pushing and adapted to excavate the ground by pushing thrust cylinder while rotating the casing pipe at the motor.

3) A gripping means for gripping the casing pipe, a thrust cylinder capable of supporting and lowering the gripping means, a motor rotating the gripping means, and a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder. When excavating the ground with a casing pipe having a cutter bit at the tip, using a casing driver equipped with a casing driver, the pressure on the cylinder side of the thrust cylinder is controlled in a casing driver excavation control device that controls so as to prevent runaway of the casing pipe. And a thrust cylinder pressure measuring means for measuring at least the cylinder-side pressure of the rod-side pressure, and a casing driver control mechanism to which a measurement result of the thrust cylinder pressure by the pressure measuring means is inputted. Of this casing driver The control mechanism extends the thrust cylinder so as to separate the cutter bit from the ground and at the same time the thrust cylinder pressure of the thrust cylinder is measured based on the result of measurement by the pressure measurement means of the thrust cylinder measured with the motor rotated. And a control function of controlling the relief valve to set the set pressure so that the supporting force for supporting the gripping means does not fall below the pressure on the side.

4) In a casing driver excavation control method for controlling escape of a casing pipe similar to 1) using a hydraulic motor as a motor for rotationally driving the gripping means, the cutter bit can be separated from the ground. A first step of extending the thrust cylinder so as to leave a stroke and gripping the casing pipe with gripping means;
The casing pipe gripped by the gripping means is raised by extending the thrust cylinder so as to separate the cutter bit from the ground, and is rotated by driving a hydraulic motor. Thus, the casing pipe is raised and rotated. In this state, at least the cylinder-side pressure and the rod-side pressure of the thrust cylinder are measured, and the self-set load obtained based on the measurement result is supported by the thrust cylinder cylinder-side pressure. Set the pressure of the relief valve so that the supporting force does not fall below
A third step of measuring the drive pressure of the hydraulic motor while the casing pipe is raised and rotated, obtaining a value relating to the rotational torque of the hydraulic motor based on the measurement result, and measuring a value relating to the peripheral surface friction torque; and While excavating the ground by pushing the casing pipe with a thrust cylinder while rotating it with a hydraulic motor, the driving pressure of the hydraulic motor is set to the sum of the preset value related to the excavation torque and the value related to the peripheral surface friction torque. And a fourth step of pushing the casing pipe with a thrust cylinder so as to approximate the actual value of the rotational torque of the hydraulic motor obtained based on the hydraulic motor. I did it.

5) In the excavation control method of the casing driver for controlling the escape of the casing pipe in the same manner as in 4), the thrust cylinder is extended so that the cutter bit is separated from the ground by the casing pipe gripped by the gripping means. A first step of increasing the rotation of the thrust cylinder by rotating the casing pipe and rotating the casing pipe while rotating the casing pipe. Measure, and set the relief valve set pressure so that the self-sinking load obtained based on the measurement result does not fall below the supporting force for supporting the gripping means with the cylinder-side pressure of the thrust cylinder,
Similarly, the driving pressure of the hydraulic motor is measured while the casing pipe is raised and rotated, and a value related to the rotational torque of the hydraulic motor is determined based on the measurement result to measure a value related to the circumferential friction torque. After releasing the gripping of the casing pipe by the gripping means, the third step of extending the thrust cylinder so that the casing pipe can be pushed in and gripping the casing pipe with the gripping means, and rotating the casing pipe by a hydraulic motor While excavating the ground by pushing it with a thrust cylinder while rotating, the rotation of the hydraulic motor obtained based on the driving pressure of the hydraulic motor with respect to the sum of the set value related to the preset Thrust cylinders of casing pipes are set so that the actual torque values are close to each other. By a fourth step of pushing in Da,
The ground excavation performed by the casing pipe is controlled by using the casing driver.

6) In a casing driver excavation control device for controlling so as to prevent runoff of a casing pipe as in 3) using a hydraulic motor as a motor for rotating the gripping means, a cutter bit is pulled away from the ground. Detecting means capable of detecting that the pressure is on, thrust cylinder pressure measuring means for measuring at least the cylinder-side pressure of the thrust cylinder-side pressure and the rod-side pressure, and driving for measuring the driving pressure of the hydraulic motor The pressure measurement means, the measurement result of the pressure measurement means of the thrust cylinder is input, so that the self-sinking load obtained based on the measurement result, the supporting force for supporting the gripping means by the cylinder side pressure of the thrust cylinder does not fall below The measurement result of the relief valve setting means for setting the set pressure of the relief valve and the driving pressure measurement means are input. Rotation torque calculation means for calculating a value relating to the rotation torque of the hydraulic motor at the time of rotation of the hydraulic motor based on the measurement result; and rotation torque calculation means when the detection means detects that the cutter bit is separated from the ground. With respect to the sum of the value related to the rotation torque of the hydraulic motor calculated in the above and the preset value related to the excavation torque, the actual value related to the rotation torque of the hydraulic motor calculated by the rotation torque calculation means when excavating the ground with the casing pipe Thrust cylinder control means for controlling the driving of the thrust cylinder so as to bring the values closer to each other is provided.

The first invention, the second invention, the fourth invention and the fifth invention of this application relating to the excavation control method of the casing driver are all provided for setting the set pressure of the relief valve. The base self-sinking load is determined by raising the casing pipe so that the cutter bit is separated from the ground and rotating the casing pipe. The friction between the peripheral surface of the casing pipe and the ground in a state where the supporting force does not act is incorporated. Therefore, when the ground is actually excavated and press-fitted with the casing pipe, the self-sinking load acting on the thrust cylinder is accurately reflected. Therefore, when the set pressure of the relief valve is set so as to prevent the escape of the casing pipe, the set pressure is no longer set unnecessarily, and the energy loss at the relief valve is reduced. Can be. In particular, in the first invention and the fourth invention of this application, a relief valve setting and the like are performed at a start stage of a casing pipe pushing process started by elongating the thrust cylinder and gripping the casing pipe. A series of steps from the first step to the third step are united so as to be merged, and these steps can be performed along the process of performing the pressing step, so that the pressing operation of the casing pipe can be efficiently performed. It can be carried out.

A third invention of this application relating to a casing driver excavation control device comprises means for carrying out the first invention and the second invention of this application relating to a casing driver excavation control method. The sixth invention of this application relating to a driver excavation control device is provided with means for implementing the fourth invention and the fifth invention of this application relating to a casing driver excavation control method. As in each of the inventions relating to the driver excavation control method, when the set pressure of the relief valve is set so as to prevent the escape of the casing pipe, energy loss at the relief valve can be reduced. Also, the fourth invention of this application,
In the fifth invention and the sixth invention, the set value relating to the rotation torque of the hydraulic motor is set based on the excavation torque which is the most important factor in preventing damage to the cutter bit of the casing pipe and performing efficient excavation. Then, it can be set to an appropriate value corresponding to the actual excavation work.

(B) Means for Solving the Second Technical Problem The second technical problem is described in claim 11
The present invention according to the seventh aspect of the present invention solves the above problems, and employs the following 7) as means for that purpose.

7) The casing pipe was gripped by the gripping means using a gripping means for gripping the casing pipe, a thrust cylinder supporting the gripping means and capable of moving up and down, and a motor for rotating the gripping means. A first step of raising the casing pipe by extending a thrust cylinder so as to separate the cutter bit from the ground and rotating the casing pipe by driving a motor;
With the casing pipe rotated and raised in this manner, at least the cylinder-side pressure of the cylinder-side pressure and the rod-side pressure of the thrust cylinder is measured, and a value relating to the self-destroying load is calculated based on the measurement results. The self-sinking load acting on the thrust cylinder is measured by the second step.

A seventh invention of this application relating to a method of measuring a self-submersion load of a casing driver is to measure a self-submersion load while rotating a casing pipe while pulling a cutter bit away from the ground and rotating the casing pipe. Therefore, the self-sinking load measured in this manner is, as described above, the frictional force between the peripheral surface of the casing pipe and the ground in a state where the supporting force of the casing pipe by the ground does not act. Therefore, according to the present invention, the self-sinking load acting on the thrust cylinder during excavation with the casing pipe can be accurately measured.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, how the inventions of this application relating to the excavation control method, the excavation control device, the self-settling load measuring method and the peripheral surface friction torque measuring method of these casing drivers are actually embodied will be described. Are described based on FIGS. 1 to 7 to clarify embodiments of each invention. FIG. 1 is a hydraulic circuit diagram showing an example of a hydraulic circuit of a casing driver for explaining each invention of this application,
FIG. 2 is a flowchart showing an example of a casing driver excavation control method for explaining each invention of this application, and FIG.
FIG. 4 is a diagram showing a control function useful for control in the hydraulic circuit diagram of FIG. 1 by the casing driver excavation control method and the excavation control device of the present invention, and FIG. 4 illustrates the significance of the control function of FIG. FIG. 5 is a conceptual diagram showing a relationship between a clearance angle of a cutter bit and a cutting locus for cutting, FIG. 5 is a block diagram showing an example of a casing driver excavation control device for explaining each invention of this application, and FIG. FIG. 7 is a hydraulic circuit diagram showing another example of a hydraulic circuit of a casing driver for describing each invention of the present invention, and FIG. 7 is a hydraulic circuit diagram of FIG. 6 by a digging control method and a digging control device of a casing driver of the invention of this application. FIG. 6 is a diagram showing a control function useful for controlling the control of FIG. In these figures, the parts denoted by the same reference numerals as those in FIGS. 8 to 10 represent the same parts as those in FIGS.

The casing driver used when embodying each invention of this application is a casing gripping band 9 as a gripping means for gripping the casing pipe 10 and the casing gripping band 9 is supported and raised and lowered. A thrust cylinder 6 and a hydraulic motor 12 for rotating the casing gripping band 9 are provided. The basic structure is the same as that of the conventionally used casing driver shown in FIGS. 8 to 10. Absent. In addition, like the casing driver used in the method described in Japanese Patent Publication No. Hei 7-15233 shown as a conventional technique, a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder is provided. 1 and 6, as in FIG. 11, schematically shows that the pinion 13 is engaged with the external gear of the rotating body 8 to rotate the rotating body 8 at a reduced speed.

First, the hydraulic circuit of FIG. 1 will be described. Reference numeral 30a denotes a forward rotation pressure of the hydraulic motor 12 (the hydraulic motor 12).
Pressure sensor for measuring the pressure on the inlet side of the
Is a pressure sensor for measuring the reverse rotation pressure (pressure on the outlet side of the hydraulic motor 12) of the hydraulic motor 12, 31a is a pressure sensor for measuring the pressure on the cylinder side (bottom side) of the thrust cylinder 6, and 31b is the thrust. This is a pressure sensor for measuring the pressure on the rod side of the cylinder 6. The pressure sensor 30a and the pressure sensor 30b are provided for measuring the differential pressure between the normal rotation pressure and the reverse rotation pressure of the hydraulic motor 12 and measuring the driving pressure thereof, and form a driving pressure measuring unit of the hydraulic motor 12. . The reverse rotation pressure of the hydraulic motor 12 is mainly generated by the resistance of the pipeline on the outlet side, and becomes a negligible value close to 0 unless the pipeline on the outlet side is extremely long. Pressure sensor 30 for measuring force
a may be regarded as the driving pressure of the hydraulic motor, but in this example, a pressure sensor 30b for measuring the pressure on the reverse rotation side is also provided for accuracy. The pressure sensor 31a and the pressure sensor 31b
This is provided for measuring an external force for shrinking the thrust cylinder 6 which works when the device is not driven, that is, a self-desiccation load. When the thrust cylinder 6 is not driven, the pressure on the rod side of the thrust cylinder 6 has a value close to 0 as in the case of the reverse rotation pressure of the hydraulic motor 12, so that the pressure sensor 31b may be omitted and only the pressure sensor 31a may be provided.

Reference numeral 32 denotes a pilot-operated relief valve capable of adjusting the set pressure according to the magnitude of the pilot pressure. Reference numeral 32a denotes an oil passage provided in an oil passage from the secondary side of the pilot-operated relief valve 32 to a tank 44. An electromagnetic switching valve 32b for hydraulic oil for opening and closing the passage is provided in a bypass line of the electromagnetic proportional relief valve 34 to allow the supply of pressure oil to the cylinder side of the thrust cylinder 6 and to be connected to the cylinder side of the thrust cylinder 6. Check valve 33 for preventing discharge of pressurized oil from the pilot operated relief valve 3
An electromagnetic switching valve 34 for switching a pilot line for guiding pilot pressure to the signal receiving portion 2; and a pilot switching valve 34 for adjusting the magnitude of the pilot pressure output to the signal receiving portion of the pilot operated relief valve 32. Electromagnetic proportional relief valve, 35 is a thrust cylinder hydraulic pump for generating a hydraulic pressure for driving the thrust cylinder 6, 36 is a power source for driving the hydraulic pump 35, 37 is the A position and the B position from the neutral position. , A 4-port, 3-position electromagnetic directional control valve for controlling the flow direction of the pressure oil so that the thrust cylinder 6 is contracted and expanded, respectively. The supply flow rate of the pressure oil to the rod side of the thrust cylinder 6 which is connected in parallel with the switching valve 37 can be adjusted by an electric signal. Electromagnetic proportional Flocon, 39 is a relief valve for the hydraulic circuit protection.

The electromagnetic switching valve 32a for hydraulic oil is normally switched to the position B as shown in FIG.
Only when an electric signal is output from the judgment processing unit 51, A
The pressure oil on the secondary side of the pilot operated relief valve 32 is released to the tank 44 by switching to the position and opening.
The pilot solenoid-operated switching valve 33 is normally switched to the position B as shown in FIG. 1, and an electric signal is output from the determination processing unit 51 described later in detail to a signal receiving unit of the solenoid-operated switching valve 33. Only when is it possible to switch to position A. The electromagnetic proportional relief valve 34 can adjust the magnitude of the set pressure in proportion to the output value of the electric signal output from the determination processing unit 51, and can increase or decrease the hydraulic pressure on the primary side. The pilot pressure of the pilot-operated relief valve 32 is introduced from an oil passage on the cylinder side of the thrust cylinder 6 and is adjusted by an electromagnetic proportional relief valve 34. As a result, the set pressure of the pilot operated relief valve 32 is set to the same value as the set pressure of the pilot operated relief valve 32.

The directional control valve 37 stops the supply and discharge of the pressure oil of the thrust cylinder 6 at the neutral position, and when switching to the A position, the pressure oil of the hydraulic pump 35 is supplied to the thrust cylinder 6.
And the flow of the pressure oil is controlled so that the pressure oil on the cylinder side of the thrust cylinder 6 can be discharged to the oil tank 44 through the pilot operated relief valve 32. When switching to the position B, the hydraulic pump 35
Pressure oil through the check valve 32b to the thrust cylinder 6
And the flow of the pressure oil is controlled so that the pressure oil on the rod side can be discharged to the oil tank 44. Therefore, when switching to the position A, the thrust cylinder 6
When the lifting frame 5 is lowered to switch to the position B, the thrust cylinder 6 is extended and the lifting frame 5 is raised. The electromagnetic proportional flow controller 38 includes an electromagnetic variable throttle valve 38a capable of adjusting an opening amount in proportion to an output value of an electric signal from the determination processing section 51, and a check provided in a bypass line of the throttle valve 38a. Valve 38b
It is composed of Then, only when the direction switching valve 37 is switched to the neutral position, the electromagnetic variable throttle valve 38a is opened by the command of the determination processing unit 51 to adjust the opening amount, and the pressure oil supplied to the rod side of the thrust cylinder 6 is adjusted. Adjust the flow rate. In FIG. 1, for convenience of explanation, only an example in which only one of the plurality of thrust cylinders 6 is controlled by such a hydraulic circuit is shown. And a plurality of thrust cylinders 6 are connected in parallel so that the pressure oil of the hydraulic pump 35 for the thrust cylinder is distributed.

Numeral 40 denotes a hydraulic motor hydraulic pump for generating hydraulic pressure for driving the hydraulic motor 12, 41 denotes a power source for driving the hydraulic pump 40, 42 denotes a relief valve for protecting a hydraulic circuit, and 43 denotes a hydraulic valve. From the neutral position to position A and B
Control the direction of the flow of the pressure oil so that the hydraulic pump 40 rotates forward and reverse respectively by switching to the position 4
An electromagnetic directional switching valve at the position of the port 3, an oil tank 44 for storing hydraulic oil, and a stroke sensor 45 for detecting a stroke of the thrust cylinder 6. The direction switching valve 43 is
When the supply and discharge of the hydraulic oil of the hydraulic motor 12 is stopped at the neutral position and switched to the position A, the hydraulic oil of the hydraulic pump 40 is supplied to the forward rotation side of the hydraulic motor 12 and the hydraulic oil on the reverse rotation side is supplied to the oil tank. The flow of pressure oil is controlled so as to be discharged to 44. When switching to the position B, the hydraulic pump 4
The pressure oil of 0 is supplied to the reverse rotation side of the hydraulic motor 12 and the flow of the pressure oil is controlled so that the pressure oil of the normal rotation side is discharged to the oil tank 44. Therefore, when the position is switched from the neutral position to the position A and the position B, respectively, the hydraulic motor 12 is driven forward and reverse, respectively, and stopped at the neutral position. Instead of independently providing the stroke sensor 45, a thrust cylinder with a built-in stroke sensor may be used.

Reference numeral 51 denotes a judgment processing unit which constitutes a control mechanism of the casing driver, and as shown in FIG. Of the thrust cylinder 6 and the rod-side pressure of the thrust cylinder 6 by the pressure sensor 31a and the pressure sensor 31b, and further, the measurement result of the stroke of the thrust cylinder 6 by the stroke sensor 45. Various calculations and control based on the calculation results are performed based on the measurement results. The determination processing section 51 constitutes a control mechanism of the casing driver together with the setting section 50 shown in FIG. 5 and the hydraulic circuit of FIG. The setting unit 50 includes an automatic / manual switch for setting whether the press-fitting process of the casing pipe 10 by the casing driver is performed automatically or manually, and a setting that is a preset excavation torque. An operation unit or the like for setting each of the excavation torque and the control function value is provided, and as shown in FIG. The determination processing unit 51 operates based on such a setting result.

The determination processing unit 51 includes, as technical means related to each invention of this application, control means for controlling the thrust cylinder 6 to extend by the height of the cutter bit 26 of the casing pipe 10, and cutter bit 26 When the stroke sensor 45 detects that the thrust cylinder is separated from the ground, the measurement results regarding the cylinder-side pressure and the rod-side pressure of the thrust cylinder 6 measured by the pressure sensor 31a and the pressure sensor 31b, respectively, are input. A self-sinking load calculating means for calculating a value relating to the self-sinking load based on the measurement result, and a supporting force for supporting the casing gripping band 9 by the pressure on the cylinder side of the thrust cylinder 6 does not fall below the self-sinking load based on the calculation result. Of relief valve to set pressure of pilot operated relief valve 32 And the measurement results relating to the forward rotation side pressure and the reverse rotation side pressure of the hydraulic motor 12 measured by the pressure sensor 30a and the pressure sensor 30b, respectively, and the hydraulic pressure during rotation of the hydraulic motor 12 is determined based on the measurement results. A rotating torque calculating means for calculating a value related to the rotating torque of the motor 12, and a hydraulic motor 1 calculated by the rotating torque calculating means when the stroke sensor 45 detects that the cutter bit 26 is separated from the ground.
The hydraulic motor 12 calculated by the rotation torque calculating means when the ground is excavated with the casing pipe 10 with respect to the sum of the value relating to the rotation torque (peripheral surface friction torque described later) and the preset value relating to the excavation torque set in advance. And a thrust cylinder control means for controlling the drive of the thrust cylinder 6 so as to bring the actual value of the rotational torque closer to the actual value.

Therefore, a method of controlling the excavation of the casing driver performed by the determination processing section 51 will be described with reference to the flowchart of FIG. When the ground is excavated with the casing pipe 10 using the casing driver while the ground is excavated, usually, the rotation speed of the casing pipe 10, that is, the rotation speed of the hydraulic motor 12 is not changed and the pushing speed of the casing pipe 10, that is, the thrust Since only the pushing speed of the cylinder 6 is changed so that the excavation torque becomes an appropriate value, in the excavation control method of the casing driver described below, the hydraulic pressure is maintained until at least one press-in step is completed. The rotation speed of the motor 12 is not changed. When the step of press-fitting the casing pipe 10 with the casing driver is performed manually, the automatic setting in the setting section 50 of the control mechanism of the casing driver is performed.
Set the manual switch to manual. Then,
The determination processing unit 51 issues a command by an electric signal to the switching valve 33 and the electromagnetic proportional flow controller 38 in the hydraulic circuit of FIG. 1 to operate them as follows. a) The switching valve 33 is switched to the position B. b) Electromagnetic variable throttle valve 38 in electromagnetic proportional flow controller 38
a is fully closed.

When the switching valve 33 is switched to the position B as in a), the pilot port of the pilot operated relief valve 32 communicates with the tank 44, so that the pilot operated relief valve 32 has a set pressure of 0 kg / cm. It becomes ² and there is no passage resistance. In addition, the electromagnetic proportional floor controller 3
8 is closed as in b), the electromagnetic proportional flow controller 38 is closed.
The pressure oil is prevented from flowing to the rod side of the thrust cylinder 6 through the oil passage of the hydraulic pump 3.
5 can be supplied only to the rod side of the thrust cylinder 6 through the direction switching valve 37. In such a state, when the direction switching valve 37 is switched to the position A by manually operating an operation means (not shown) such as an operation lever, the thrust cylinder 6 can be contracted. The thrust cylinder 6 can be extended. Thus, the press-fitting step of the casing pipe 10 can be performed manually by a normal method.

Next, a method of performing the excavation control method of the casing driver of the present invention to perform automatic excavation control will be described. When performing automatic excavation control, switch the automatic / manual changeover switch to automatic, and operate the operation unit that sets the set excavation torque and control function value to set the excavation torque and control function value, It is set to a value suitable for excavation conditions while taking into account. In this example,
In performing the automatic excavation control, a manual operation is performed in the first step a).

A) Extension of the thrust cylinder and gripping of the casing pipe 10 First, the directional control valve 37 is manually switched to the position B so that the stroke capable of extending the thrust cylinder 6 by the height of the cutter bit 16 is left. Extend the thrust cylinder 6. That is, when the maximum stroke of the thrust cylinder 6 is Lo and the height of the cutter bit 26 of the casing pipe 10 is Lst, the thrust cylinder 6 is extended by Lo-Lst, and then the direction switching valve 37 is extended.
Is manually switched to the neutral position. In that case, whether or not the thrust cylinder 6 has been extended by Lo-Lst is confirmed by the operator monitoring an instrument displaying the measurement result of the stroke sensor 45. Next, the casing pipe 10 is gripped by the casing gripping band 9, and thereafter, the casing motor 10 is driven to rotate the casing gripping band 9 to rotate the casing pipe 10.

B) Re-extension of the thrust cylinder after the casing pipe is gripped. After the step a), when the automatic / manual switch of the setting unit 50 is automatically switched, the direction switching valve 37 is switched to the judgment processing unit 51. Is automatically switched to the B position in response to a command from. As a result, the pressure oil of the hydraulic pump 35 is supplied to the cylinder side of the thrust cylinder 6 through the check valve 32b, and the pressure oil of the rod side is discharged to the oil tank 44 through the discharge port of the direction switching valve 37. Elongate. When the thrust cylinder 6 extends by the height Lst of the cutter bit 26 in this way, the determination processing unit 51 determines this from the stroke value of the thrust cylinder 6 input from the stroke sensor 45, and
Return the direction switching valve 37 to the neutral position. As a result, the casing pipe 10 rises by Lst, and the cutter bit 26
Is kept separated from the ground. In that case,
The casing pipe 10 is rotated by being gripped by a casing gripping band 9 driven to rotate by a hydraulic motor 12. In this example, the casing pipe 10 is rotated in advance as described above.
May be rotated after being raised by Lst.

C) Measurement by calculation of self-subsidence load In a state where the casing pipe 10 is rotated and lifted away from the ground in this manner, the pressure sensor 31
Since the pressure sensor 31a and the pressure sensor 31b measure the cylinder-side pressure and the rod-side pressure of the thrust cylinder 6, respectively, the measurement results are sent to the determination processing unit 51. The judgment processing unit 51 first calculates the self-subsidence load according to the following equation 2 based on these measurement results. Formula 2 Wp = (Po × So−Pt × St) × N In the above equation, Wp is a self-subsidence load Po is a pressure on the cylinder side of the thrust cylinder 6 So is a pressure receiving area on a cylinder side of the thrust cylinder 6 Pt is a pressure receiving area on the cylinder side of the thrust cylinder 6 The pressure St on the rod side is the pressure receiving area N on the rod side of the thrust cylinder 6, and the number N of the thrust cylinders 6 to be driven.

The self-sinking load W thus measured by the calculation
Since p is measured in a state where the casing pipe 10 is separated from the ground and rotated, the friction between the peripheral surface of the casing pipe 10 and the ground in a state where the supporting force of the casing pipe 10 by the ground does not act is taken. It is measured by interweaving. Therefore, when actually excavating and press-fitting the ground with the casing pipe 10, the thrust cylinder 6
It can be said that it accurately reflects the self-sinking load that acts on
The self-subsidence load Wp is stored in a storage device and can be output as needed, such as to be displayed on display means, thereby constituting a self-subsidence load measuring device.

D) Measurement by calculation of peripheral surface friction torque In a state in which the casing pipe 10 is rotated in the step (b) and raised so as to be separated from the ground,
In this example, the rotational torque of the hydraulic motor 12 can be appropriately controlled as will be described later by measuring the peripheral friction torque in addition to the self-set load Wp. The pressure sensor 30a and the pressure sensor 30b measure the forward rotation pressure (pressure on the inlet side of the hydraulic motor 12) and the reverse rotation side (pressure on the same outlet side) of the hydraulic motor 12, respectively. , These measurement results are also sent. The determination processing unit 51 calculates the actual value T ′ of the cutter rotation torque, which is the rotation torque of the hydraulic motor 12, according to the following Expression 3 based on these measurement results. Equation 3 T ′ = β × (Ps−Pg) × (Zg / Zp) × Nm In the above equation, T ′ is the cutter rotation torque which is the actual value of the rotation torque of the hydraulic motor 12 β is the hydraulic motor output shaft torque coefficient Ps Is the forward rotation pressure of the hydraulic motor 12 (pressure on the inlet side of the hydraulic motor 12) Pg is the reverse rotation pressure of the hydraulic motor 12 (pressure on the outlet side of the hydraulic motor 12) Zg is the external teeth provided on the outer peripheral portion of the rotating body 8 The number of teeth Zp of the gear is the number of teeth of the pinion 13 and the number Nm is the number of hydraulic motors 12. The hydraulic motor output shaft torque coefficient β is a coefficient corresponding to the ratio of the effective value to the theoretical value of the output shaft torque of the hydraulic motor 12.

The cutter rotation torque T ′ required for press-fitting the casing pipe 10 while excavating the ground with the cutter bit 26 includes those that are purely consumed for excavating the ground, the peripheral surface of the casing pipe 10 and the ground. Some are consumed by friction with. Now, the rotational torque of the hydraulic motor 12 consumed by the excavation of the ground by the cutter bit 26 is defined as the excavation torque Tc, and the rotational torque of the hydraulic motor 12 consumed by the friction between the peripheral surface of the casing pipe 10 and the ground is determined by the peripheral friction. Assuming the torque Tm, the cutter rotation torque T ′ is
It can be represented by the following Equation 4. Equation 4 T ′ = Tc + Tm In this example, the peripheral friction torque Tm together with the self-subsidence load Wp
Is measured, in which case the casing pipe 10
Is measured by calculating the cutter rotation torque T ′ using Equation 3 in a state where the cutter rotation torque is increased in the same manner as when measuring the self-subsidence load Wp. The cutter rotation torque T ′ thus measured is measured in a state where the casing pipe 10 is lifted and the cutter bit 26 is separated from the ground, that is, in a state where it is impossible to excavate the ground with the cutter bit 26. A state in which the rotational torque of the hydraulic motor 12 consumed for excavation of the ground does not occur, that is, Equation 4
It is measured in the state of the middle excavation torque Tc = 0. Therefore, since the cutter rotation torque T ′ = Tm, the cutter rotation torque T ′ thus measured accurately reflects the peripheral surface friction torque Tm generated when the ground is actually excavated and press-fitted with the casing pipe 10. It can be said that. The cutter rotational torque T ′ is stored in a storage device and can be output as required, such as to be displayed on display means, thereby constituting a peripheral surface friction torque measuring device.

E) Setting of the set pressure of the pilot-operated relief valve After calculating the self-subsidence load Wp by the method shown in c), the judgment processing section 51 operates the pilot operation for preventing the casing pipe 10 from running away. The set pressure of the relief valve 32, in other words, the set pressure of the pilot-operated relief valve 32 for preventing the lifting frame 5 from lowering due to the self-sinking load is calculated based on the self-sinking load Wp. , The relief pressure of the valve 32 is set. Since the set pressure of the pilot operated relief valve 32 is equal to the set pressure of the electromagnetic proportional relief valve 34, the set pressure of the pilot operated relief valve 32 is set by changing the set pressure of the electromagnetic proportional relief valve 34 to the following value. The calculation is performed according to Equation 5. Equation 5 Pr = Wp / (So × N) + A In the above equation, Pr is the set pressure of the electromagnetic proportional relief valve 34, A is a margin value. The meanings of Wp, So, and N are the same as those in Equation 2.
Since the characteristics of the electromagnetic proportional relief valve vary slightly depending on the product, a slight error occurs in the set pressure for each product. The margin value A is added to absorb such a control characteristic individual difference (control value-control characteristic of the set pressure of the electromagnetic proportional relief valve) of the electromagnetic proportional relief valve, and is added to the set pressure of the electromagnetic proportional relief valve 34. Even if an error occurs, the value is set so as to prevent the casing pipe 10 from running away.

To prevent the ground from escaping when excavating the ground with the casing pipe 10, the supporting force for supporting the casing gripping band 9 by the pressure on the cylinder side of the thrust cylinder 6, that is, the lifting frame 5 is moved by the thrust cylinder 6.
The set pressure of the pilot-operated relief valve 32 may be set so that the supporting force for supporting the pressure relief valve is at least equal to the self-subsidence load Wp. Therefore, in the determination processing unit 51, the four thrust cylinders 6 shown in FIG. 8 cooperate with each other to make the sum of the supporting forces for supporting the casing gripping band 9 at least equal to the self-sinking load Wp. What is necessary is just to calculate the set pressure of the set pressure of the proportional relief valve 34. In this example, when the set pressure Pr of the electromagnetic proportional relief valve 34 is determined, a margin value A is added to the support force for supporting the casing gripping band 9 with the thrust cylinder 6 so that the margin value A is added to the support force. Is slightly larger than the self-sinking load Wp, but the point is that the pilot-operated relief valve 32 is used as long as the supporting force for supporting the casing gripping band 9 with the thrust cylinder 6 does not fall below the self-sinking load Wp. An appropriate value may be selected from a design so as to reduce energy loss.

F) Calculation of scheduled cutter rotation torque during excavation After calculating the peripheral surface friction torque Tm by the method shown in d), the judgment processing section 51 determines the damage of the cutter bit 26 based on the peripheral surface friction torque Tm. Is calculated in accordance with the following equation (6), which is a set value of the scheduled drilling cutter rotation torque T, which is a set value of the rotation torque of the hydraulic motor 12 for preventing the drilling and enabling efficient drilling with the cutter bit 26.

Equation 6 T = Ts + Tm In the above equation, Ts is a set excavation torque which is a set value of the excavation torque Tc.

In this example, the set excavation torque Ts is
The highest priority is given to preventing damage to the cutter bit 26 while taking into account the properties of the ground and the standard of the cutter bit 26, and at this time, consideration is also given to enabling efficient excavation.

To prevent the cutter bit 26 from being damaged,
Originally, it is necessary to set the excavation torque Tc, which is the purely consumed rotation torque for excavating the ground, to an appropriate value among the rotational torques of the hydraulic motor 12. However, conventionally, a method of actually measuring the peripheral friction torque Tm during the excavation work of the casing driver has not been established, so that the ratio between the excavation torque Tc and the peripheral friction torque Tm of the rotation torque of the hydraulic motor 12 is determined. Therefore, the actual value of the excavation torque Tc could not be accurately grasped. For this reason, the planned cutter rotation torque T during excavation for preventing the damage of the cutter bit 26 is empirically predicted and determined with an approximate guide while taking into account construction conditions such as soil quality, earth removal status, excavation depth and the like. . On the other hand, in the method (f), the excavation torque Tc, which is the most important factor in preventing damage to the cutter bit 26 and performing efficient excavation, is directly set and then set. The planned cutter rotation torque T during excavation is set based on the set excavation torque Ts and the actually measured value of the peripheral surface friction torque Tm. Since the value of the excavation torque Tc necessary for preventing damage to the cutter bit 26 and performing efficient excavation has already been determined from previous research and results, if this method is used, the planned cutter for excavation can be used. Rotation torque T
Can be set to an appropriate value according to the actual excavation work.

G) The casing pipe descends to the ground due to the reduction of the thrust cylinder. The casing pipe 10 in which the thrust cylinder 6 is re-extended in the step b) and raised by the height Lst of the cutter bit 26 is replaced with the thrust cylinder 6. It is lowered on the ground by the reduction of Lst. These operations are performed by the judgment processing unit 51.
Start with the command of In response to the command from the determination processing unit 51, the electromagnetic switching valve 32a for hydraulic oil and the electromagnetic switching valve 33 for pilot are both switched to the position A, and as a result, the electromagnetic proportional relief valve set in e) The pilot pressure of the set pressure Pr of 34 acts on the signal receiving portion of the pilot-operated relief valve 32 through the pilot electromagnetic switching valve 33, whereby the set pressure of the pilot-operated relief valve 32 becomes an electromagnetic proportional relief valve. The same value as the set pressure of 34 is set. In this step, the electromagnetic proportional flow controller 38 also operates, and the opening amount is adjusted in proportion to the output value of the electric signal from the determination processing unit 51 to adjust the pushing speed of the casing pipe 10 of the thrust cylinder 6. In this case, in the step (g), a command is issued from the determination processing unit 51 so that the pushing speed becomes minimum. At this time, the direction switching valve 37 is in the neutral position (the point B).
In the position where it was finally operated in the step of

Then, the pressure oil of the hydraulic pump 35 for the thrust cylinder is adjusted to the minimum flow rate by the electromagnetic proportional flow controller 38 and supplied to the rod side of the thrust cylinder 6, and the pressure oil on the cylinder side is used for pilot operation. While being held at the set pressure Pr by the relief valve 32, the hydraulic fluid is discharged to the tank 44 through the electromagnetic switching valve 32 a for hydraulic oil. As a result, the thrust cylinder 6 is reduced at a speed corresponding to the flow rate of the pressure oil of the electromagnetic proportional flow controller 38, and the casing pipe 10 is lowered on the ground at the lowest speed.
The reason for lowering the casing pipe 10 at a low speed in this way is that when the casing pipe 10 comes into contact with the ground, a sharp load is applied to the cutter bit 26 and the cutter bit 26
In order to prevent any damage. When the casing pipe 10 descends on the ground due to the reduction of the thrust cylinder 6 by Lst, the determination processing unit 51 detects this from the stroke value of the thrust cylinder 6 input from the stroke sensor 45.

(H) Calculation of cutter rotation torque during excavation After the casing pipe 10 has been lowered onto the ground, the excavation of the ground using the cutter bit 26 is continuously advanced. The calculation of T 'is started. The cutter rotation torque T ′ at the time of excavation is calculated according to Equation 3 as in the case where the peripheral surface friction torque Tm is calculated in d). Since the cutter rotation torque T ′ during excavation is the actual value of the rotation torque of the hydraulic motor 12 required when excavating the ground with the cutter bit 26, the cutter rotation torque T ′ during excavation calculated by Equation 3 In addition to the peripheral friction torque Tm, the excavation torque Tc, which is the rotational torque of the hydraulic motor 12 consumed in excavating the ground, is naturally included in the excavation torque Tm.

(I) Control of the pushing speed of the casing pipe The judgment processing unit 51 continuously calculates the cutter rotation torque T ′ during the excavation when excavating the ground with the cutter bit 26, and further calculates the calculation result. And the set cutter rotation torque T during excavation as the set value calculated in f).
And a deviation ΔT (ΔT = TT ′) from the actual value and the actual cutter rotation torque T ′ during excavation. Then, based on the deviation ΔT, a command value is output to the electromagnetic proportional flow controller 38 in accordance with the control function of FIG. 3 which defines the relationship between the deviation ΔT and the electromagnetic proportional flow command value, and the opening amount thereof is controlled. The pushing speed of the casing pipe 10 is controlled by controlling the supply flow rate to the rod side of 6. More specifically, FIG. 3 shows three graphs having different gradients. The graph shows the deviation ΔT determined in consideration of the properties of the ground such as the hardness of the ground and the electromagnetic force. This is a control function with a proportional flow control command value. Such a control function may be appropriately determined by the designer of the casing driver in design based on past know-how. In this example, since the cutter bit to be used is specified, only the properties of the ground are considered. However, when the cutter bit to be used is not specified, the performance of the cutter bit is also considered.

When automatic excavation control is performed according to this example, an appropriate one suitable for the properties of the ground is selected from the control functions shown in FIG.
When the deviation ΔT becomes negative during excavation of the ground, the cutter bit 26 is overloaded,
The command value to the electromagnetic proportional flow controller 38 is set to zero, and the pushing of the casing pipe 10 by the thrust cylinder 6 is stopped. Conversely, when the deviation ΔT becomes positive,
Since the cutter bit 26 is still lightly loaded, the command value to the electromagnetic proportional floor controller 38 is determined according to a preset control function, so that the pushing speed of the casing pipe 10 is relatively increased. As a result, the casing pipe 10 uses the scheduled cutter rotation torque T ′ at the time of digging as the set value with the cutter rotation torque T ′ at the time of digging as the actual value.
Thrust cylinder 6
, And is always driven to rotate with an appropriate excavation torque Tc, so that the cutter bit 26 can be prevented from being damaged. The operation of the electromagnetic proportional flow controller 38 performed by the command value determined by the determination processing unit 51 is performed by the flow control unit 5.
3 (see FIG. 5).

By performing such automatic excavation control,
Although the situation in which the cutter bit 26 is damaged is greatly improved, in this example, since the rear surface of the cutter bit 26 is devised to prevent abnormal wear, using FIGS. 3 and 4, This point is also mentioned. When the pushing speed of the casing pipe 10 is increased when the deviation ΔT is positive, if the pushing speed is excessively increased, FIG.
In the excavation ground, the tip 26a of the cutter bit 26
, The portion other than the tip, that is, the back surface of the relief angle portion 26b of the cutter bit 26 may be pressed against the undigged excavated ground, causing abnormal wear. Therefore, in this example, the deviation ΔT
When the pushing speed of the casing pipe 10 is increased in the case where is positive, the pushing speed of the casing pipe 10 is increased by providing an upper limit value to the electromagnetic proportional floor controller command value which is the command value of the determination processing unit 51 to the electromagnetic proportional floor controller 38. I try to restrict.

Now, the diameter of the casing pipe 10 is 100
Attach a cutter bit 26 on the circumference of the tip of the casing pipe 10 using a pipe of 1 mm. p. m
And the pushing speed of the casing pipe 10 at this time is V (mm / min).
And Then, the casing pipe 10 becomes 1
During rotation, the tip of the tip 26a
The ground is cut while turning while drawing a line having a length of (mm), and is pushed downward by a distance of V (mm). In other words, the gradient of the cutting trajectory at the tip of the tip 26a when excavating the ground with the cutter bit 26 can be said to be V / 1000π. The angle defining the slope of the cutting locus of such chips tip, where it is referred to as theta ₁ referred to as the angle of the cutter bit cutting trajectory. Now
Assuming that V = 500 (mm / min), the angle θ ₁ of the cutter bit cutting trajectory in this case can be obtained by the following equation. θ ₁ = tan ~ ¹ (500 / 1000π) = 9.04 [d
eg (degree)] Since the clearance angle θ of the cutter bit is generally 15 deg, in this case, the clearance angle portion 2 of the cutter bit 26 is used.
There is no possibility that the rear surface of 6b is pressed against the unexcavated excavation ground and abnormally worn.

However, when the angle θ ₁ of the cutter bit cutting trajectory is larger than the clearance angle θ of the cutter bit, the clearance angle portion 26b of the cutter bit 26 comes into contact with the ground, and the wear proceeds. Taking this into consideration, when the pushing speed V of the casing pipe 10 when the clearance angle θ of the cutter bit is 15 deg is obtained, it can be obtained by the following Expression 7. Equation 7 V = tan (15) × 1000π = 872 (mm / mi)
n) Therefore, if the pushing speed V of the casing pipe 10 does not exceed 872 (mm / min), the clearance angle portion 26b of the cutter bit 26 does not wear on the back surface, and therefore, the electromagnetic proportional flow control command value The upper limit of
The reduction speed of the thrust cylinder 6 is 872 (mm / mi)
n). The upper limit value of the electromagnetic proportional flow controller command value is illustrated by a dotted line and a continuous solid line on the plus coordinate plane in FIG.

In this example, the upper limit value of the electromagnetic proportional flow controller command value is calculated after setting the rotation speed of the casing pipe 10 to a fixed value (1 rpm). An arithmetic expression for calculating the upper limit value is stored in the determination processing unit 51 and means for measuring the rotation speed of the casing pipe 10 is provided. By inputting the actual value of the rotation speed to the determination processing unit 51, The upper limit value of the proportional flow control command value may be calculated one by one using the calculation formula. When the excavated ground is a boulder layer or a ground where an obstacle may appear, the cutter rotational torque T ′ fluctuates drastically when the ground is excavated with the cutter bit 26, and the cutter bit 26 May be subjected to a sudden load. In preparation for such a case, in this example, the gradient of the graph of the control function in FIG. 3 can be arbitrarily changed. When there is a possibility that a sudden load may be applied to the cutter bit 26, the gradient of the graph of the control function in FIG. Of the cutter bit 26 so as to prevent a sudden load from being applied to the cutter bit 26.

(7) Thrust cylinder reduction stop When the thrust cylinder 6 is reduced to the limit, the judgment processing unit 51
Detects this from the stroke value of the thrust cylinder 6 from the stroke sensor 45, makes the command value of the electromagnetic proportional flow controller 38 zero, stops the reduction of the thrust cylinder, and stops the rotation of the hydraulic motor 12. Then, after releasing the gripping of the casing pipe 10 by the casing gripping band 9, the operation is again shifted to the operation of extending the thrust cylinder 6 by Lo-Lst by a manual operation. ) Is repeated. If necessary, a new casing pipe 10 having no cutter bit 26 is added to the press-fitted casing pipe 10. Each time one press-fitting process is completed, the kinetic friction force and the circumferential friction torque Tm of the peripheral surface of the casing pipe 10 which increase in accordance with the progress of the press-fitting of the casing pipe 10 are incorporated, and the electromagnetic proportional relief based on the self-settling load Wp. Since the set pressure of the valve 34 and the scheduled cutter rotation torque T during excavation are reviewed and reset, the set pressure of the pilot-operated relief valve 32 for preventing the escape of the casing pipe 10 and the excavation work are properly performed. Of the rotational torque of the hydraulic motor 12 is set to an appropriate value in accordance with the progress of press-fitting of the casing pipe 10. As a result, the escape of the casing pipe can be prevented while reliably reducing the energy loss in the pilot-operated relief valve 32, and the excavation work by the casing driver can always be properly performed.

In the excavation control method of the casing driver described above, in the steps of a) to nu), the extension of the thrust cylinder 6 and the gripping of the casing pipe 10 are started in the step a) of pushing the casing pipe 10. The point where a stroke that can be extended by the height of the cutter bit 26 when the thrust cylinder 6 is extended is left is that the setting of the set pressure of the pilot-operated relief valve 32 and the setting of the expected cutter rotational torque T during excavation are performed. This is an operation for performing an operation. Therefore, in this example, at the start of the pushing process of the casing pipe 10, the setting pressure of the pilot-operated relief valve 32 and the calculation of the scheduled cutter rotation torque during excavation are performed in a) to f).
And the setting of the set pressure of the pilot-operated relief valve 32 and the calculation of the expected cutter rotation torque during excavation can be performed along the way of performing the pushing process of the casing pipe 10. In addition, the operation of pushing the casing pipe can be performed efficiently.

In this embodiment, the pilot-operated relief valve 3
Although the process of setting the set pressure of 2, etc. is united,
These steps may not be combined during the step of pushing the casing pipe 10. In that case,
First, the casing pipe 10 grasped by the casing grasping band 9 is raised by extending the thrust cylinder 6 so as to separate the cutter bit 26 from the ground, and is rotated by driving the hydraulic motor 12. Next, the cylinder-side pressure Po and the rod-side pressure Pt of the thrust cylinder 6 are measured while the casing pipe 10 is raised and rotated in this manner, and a self-desiccation load Wp is calculated based on the measurement results. The set pressure of the pilot-operated relief valve 32 is set based on the above, and the forward rotation pressure Ps and the reverse rotation pressure Pg of the hydraulic motor 12 are measured while the casing pipe 10 is raised and rotated. Excavation scheduled cutter rotation torque which is a set value related to the rotation torque of the hydraulic motor 12 based on the rotation torque of the hydraulic motor 12 obtained based on the value related to the peripheral surface friction torque Tm and the set value related to the excavation torque, ie, the set excavation torque Ts. Set T. Thereafter, the casing pipe 10 is lowered onto the ground by compressing the thrust cylinder 6 in the same manner as in the above step g) to release the casing pipe 10 from being gripped by the casing gripping band 9. In this case, when the cutter bit 26 is slightly separated from the ground in the first step, the step of contracting the thrust cylinder 6 is omitted, and the process immediately shifts to the step of releasing the gripping of the casing pipe 10. Good. After the step of setting the set pressure of the pilot-operated relief valve 32 has been completed in this way, the step of pushing the casing pipe 10 is started. For this reason, the thrust cylinder 6 is extended so that the casing pipe can be pushed. The pipe is gripped by the gripping means, and thereafter, the casing pipe 10 is pushed in by the above-mentioned steps (h) to (h).

Another example of a hydraulic circuit of a casing driver for carrying out each invention of this application will be described with reference to FIG. The hydraulic circuit of FIG. 6 is different from the hydraulic circuit of FIG. 1 only in the method of adjusting the supply flow rate of the pressurized oil to the rod side of the thrust cylinder 6, and is otherwise basically the same as that of FIG. Does not change. That is, in the case of adjusting the supply flow rate of the pressure oil to the rod side of the thrust cylinder 6, in the hydraulic circuit of FIG. In the hydraulic circuit of FIG. 6, a part of the pressure oil supplied to the rod side of the thrust cylinder 6 is made to escape to the tank 44, and the flow rate of the oil released is adjusted to indirectly control the oil pressure. To adjust.

Therefore, the structure of the circuit which is different from the hydraulic circuit of FIG. 1 will be specifically described. The hydraulic circuit shown in FIG. 6 differs from the hydraulic circuit shown in FIG. 1 in that an oil passage provided in parallel with the direction switching valve 37 and provided with an electromagnetic proportional flow controller 38 and an electromagnetic switching valve 32 for hydraulic oil.
Instead of eliminating the oil passage provided with a, an oil passage for releasing a part of the pressure oil sent from the hydraulic pump 35 to the direction switching valve 37 to the tank 44 is provided, and the electromagnetic proportional flow controller 38 is provided in this oil passage. It is provided. The hydraulic circuit shown in FIG.
In the case of performing the press-in process of 0, the directional control valve 37 is also used in the automatic operation as in the manual operation.
To the position A to supply the pressure oil to the rod side of the thrust cylinder 6. In that case, this electromagnetic proportional flow controller 3
8 adjusts the flow rate at which a part of the pressure oil sent to the direction switching valve 37 is released to the tank 44 in accordance with a command from the determination processing unit 51, and adjusts the flow rate of the pressure oil supplied to the rod side of the thrust cylinder 6. . In the example of FIG. 6, the deviation Δ between the planned cutter rotation torque T during excavation and the cutter rotation torque T ′ during excavation is shown.
FIG. 7 shows a control function that defines the relationship between T (ΔT = TT ′) and the electromagnetic proportional flow controller command value. Accordingly, in the example of FIG. 6, by outputting a command value to the electromagnetic proportional flow controller 38 in accordance with the control function of FIG. Controlling the feed flow rate of the thrust cylinder 6 to the rod side to control the pushing speed of the casing pipe 10 so that the cutter rotation torque T ′ at the time of excavation becomes close to the expected cutter rotation torque T at the time of excavation. Becomes

As described above, the cutter rotation torque T ′ at the time of excavation is compared with the cutter rotation torque T at the time of excavation as the set value.
When the casing pipe is pushed by the thrust cylinder so as to make the relationship close to the set value, in the example described above, the pushing speed of the casing pipe 10 is controlled by adjusting the flow rate on the rod side of the thrust cylinder 6. However, the pushing force of the casing pipe 10 may be controlled by adjusting the pressure on the rod side of the thrust cylinder 6. In that case, for example, instead of eliminating the electromagnetic proportional flow controller 38 in FIG. 6, a relief valve capable of changing the set pressure in multiple stages may be provided on the secondary side of the direction switching valve 37.

However, if the pushing speed of the casing pipe 10 is controlled by adjusting the flow rate on the rod side of the thrust cylinder 6 as in the examples shown in FIGS. The control when pushing with can be performed more accurately. To describe this point, the relationship between the pushing speed V of the casing pipe 10 and the excavation torque Tc can be expressed by the following Expression 7.

Equation 7 Tc = α × (σ × B × V / R) × D / 2 where α is the cutting resistance coefficient, σ is the uniaxial compressive strength of the excavated ground, B is the cutter width, and R is the casing pipe. Since the rotation speed of 10 and D is the excavation diameter, the casing pipe 10
When the excavation control of the casing driver is performed while keeping the rotation speed of the casing pipe constant, all of these factors become constants, and the pushing speed V of the casing pipe 10 and the excavation torque Tc are in a proportional relationship. For this reason, if the pushing speed of the casing pipe 10 is controlled by adjusting the flow rate on the rod side of the thrust cylinder 6, the control when the casing pipe 10 is pushed by the thrust cylinder 6 can be performed more accurately, and the cutter Excavation control of the casing driver for preventing damage to the bit 26 and performing efficient excavation can be more reliably achieved.

When the set pressure of the pilot-operated relief valve 32 for preventing the casing pipe 10 from running away is set, in the example shown in the flow chart of FIG. C) the process;
The set pressure of the pilot-operated relief valve 32 is set by calculating the set pressure Pr of the electromagnetic proportional relief valve 34 based on the self-sinking load Wp according to Equation (5).
The set pressure Pr of the electromagnetic proportional relief valve 34 is different from that of the thrust cylinder 6.
If the pressure Po on the cylinder side and the pressure Pt on the rod side of the thrust cylinder 6 are uniquely determined, they can be directly set without going through the step (c). Therefore, the process of setting the set pressure of the pilot-operated relief valve 32 is not essential to the present invention. In short, the supporting force for supporting the gripping means with the cylinder side pressure Po of the thrust cylinder 6 increases the thrust. The pressure Po on the cylinder side of the cylinder 6 and the pressure P on the rod side
The set pressure of the pilot-operated relief valve 32 may be set by an appropriate method so that the result does not fall below the self-sinking load Wp obtained based on t. In the case of controlling the driving of the thrust cylinder 6, in the example shown in the flow chart of FIG. 2, the planned cutter rotation torque T obtained at the time of excavation obtained by adding the peripheral surface friction torque Tm to the set excavation torque Ts.
Is set to a set value, and the cutter rotation torque T 'as an actual value is set.
Is controlled so as to approach the set value. However, the set excavation torque Ts is set to the set value, and the value obtained by subtracting the peripheral friction torque Tm from the cutter rotation torque T ′ is controlled to approach the set value. The point is that the set excavation torque Ts
It is only necessary that the result be controlled so that the actual value related to the rotational torque T ′ of the hydraulic motor approaches the sum of the value related to the peripheral surface friction torque Tm and the value related to the circumferential friction torque Tm.

In the example described above, both the cylinder-side pressure Po and the rod-side pressure Pt of the thrust cylinder 6 are measured, but these cylinder-side pressure Po and rod-side pressure Pt are measured by the thrust cylinder 6. Is measured in order to determine the self-subtracting load Wp, which is an external force for shrinking the thrust cylinder 6 when the thrust cylinder 6 is not driven. Therefore, it is possible to measure only the pressure Po on the cylinder side of the thrust cylinder 6 and treat the pressure Pt on the rod side of the thrust cylinder 6 as 0 or a constant close to 0 to obtain the self-sinking load Wp.
Further, in order to measure the drive pressure of the hydraulic motor, which is the differential pressure between the forward rotation pressure Ps and the reverse rotation pressure Pg of the hydraulic motor, the hydraulic motor 1
Although both the normal rotation pressure Ps and the reverse rotation pressure Pg are measured, since the reverse rotation pressure Pg of the hydraulic motor 12 usually has a small value close to 0, only the normal rotation pressure Ps of the hydraulic motor 12 is measured. At the same time, the driving pressure of the hydraulic motor may be measured by treating the reverse rotation pressure Pg of the hydraulic motor 12 as 0 or a constant close to 0.

In the example described above, the casing pipe 10
An example in which the casing gripping band 9 is used as the gripping means for gripping the casing is shown. In this gripping means, a wedge-shaped chuck member is fitted into a gap between the ring-shaped rotating body and the casing inserted therethrough. There is also a chuck device that grips the casing by wedge action, and since this chuck device performs the same function as the casing gripping band 9, such a chuck device may be used as the gripping means. The type of gripping means used in the present invention does not matter. Also,
As means for changing the pushing speed of the thrust cylinder 6, the flow rate of the pressure oil supplied to the rod side of the thrust cylinder 6 is adjusted by using the electromagnetic proportional flow controller 38. The flow rate of the pressure oil may be adjusted using a pump.

[0074]

As is apparent from the above description, the first to sixth inventions of this application are:
According to these inventions, the relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder is employed because each of the means 1) to 6) described in the section of "Means for Solving the Problems" is adopted. The present invention provides a casing driver excavation control technique that can be used for a casing driver having a casing valve and that can reduce the energy loss at the relief valve and prevent the escape of the casing pipe. In this case, in particular, in the first invention and the fourth invention of this application, a relief valve is set at a start stage of a casing pipe pushing process started by elongating the thrust cylinder and gripping the casing pipe. A series of steps from the first step to the third step are combined so as to be integrated, and these steps can be performed along the path of performing the pressing step, so that the pressing operation of the casing pipe can be efficiently performed. Can be done In the fourth invention, the fifth invention and the sixth invention of the present application, in particular, the set value relating to the rotation torque of the hydraulic motor is used to prevent damage to the cutter bit of the casing pipe and to perform efficient excavation. Based on the most important factor above, excavation torque, it can be set to an appropriate value according to the actual excavation work, so when performing excavation control of the casing driver, prevent damage to the cutter bit of the casing pipe And more efficient excavation can be achieved more reliably than before.

When the fourth and fifth aspects of the present invention are embodied, in particular, when the means described in claim 6 is adopted, the case where the casing pipe is pushed by a thrust cylinder is adopted. The control can be performed more accurately, and the excavation control of the casing driver for preventing the cutter bit from being damaged and performing efficient excavation can be more reliably achieved. The same applies to the case where the sixth invention of this application is embodied, particularly when the means described in claim 9 is adopted. Since the seventh invention of this application employs the means of 7) described in the section of means for solving the problems, according to the seventh invention, the thrust at the time of excavation in the casing pipe is obtained. A method for measuring a self-sinking load of a casing driver that can accurately measure the self-sinking load acting on a cylinder is obtained.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram showing an example of a hydraulic circuit of a casing driver for explaining each invention of this application.

FIG. 2 is a flowchart showing an example of a casing driver excavation control method for describing each invention of this application.

FIG. 3 is a diagram showing a control function useful for control in the hydraulic circuit diagram of FIG. 1 by the casing driver excavation control method and the excavation control device of the present invention.

FIG. 4 is a conceptual diagram illustrating a relationship between a clearance angle of a cutter bit and a cutting locus for explaining the significance of the control function of FIG. 3;

FIG. 5 is a block diagram showing an example of a casing driver excavation control device for describing each invention of this application.

FIG. 6 is a hydraulic circuit diagram showing another example of a hydraulic circuit of a casing driver for describing each invention of this application.

7 is a diagram showing a control function useful for control in the hydraulic circuit diagram of FIG. 6 by the casing driver excavation control method and the excavation control device of the invention of this application.

FIG. 8 is a plan view showing an example of a casing driver generally used conventionally.

FIG. 9 is a right side view of FIG.

FIG. 10 is a front view of FIG. 8;

FIG. 11 is an explanatory diagram of a self-set load acting on a thrust cylinder during excavation by a casing driver.

[Explanation of symbols]

 Reference Signs List 4 Base frame 5 Elevating frame 6 Thrust cylinder 8 Rotating body 9 Casing gripping band 10 Casing 11 Band cylinder 12 Hydraulic motor 13 Pinion 26 Cutter bit 26a Cutter bit 26 tip 26b Relief angle portion of cutter bit 26 30a, 30b For hydraulic motor Pressure sensors 31a, 31b Pressure sensor for thrust cylinder 32 Pilot operated relief valve 32a Electromagnetic switching valve for hydraulic oil 33 Electromagnetic switching valve for pilot 34 Electromagnetic proportional relief valve 35 Hydraulic pump for thrust cylinder 36 Power source (For thrust cylinder) 37 Electromagnetic directional switching valve 38 Electromagnetic proportional flow controller 38a Electromagnetic variable throttle valve 38a 40 Hydraulic pump for hydraulic motor 41 Power source (for hydraulic motor) 43 Electromagnetic directional switching valve 44 Oil tank 5 stroke sensor 50 setting unit 51 determines the processing unit 52 the relief valve control unit 53 electromagnetic proportional Flocon controller

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hiroshi Kusumi 650, Kandate-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. (72) Inventor Toshihisa Ishii 650, Kandamachi, Tsuchiura-shi, Ibaraki Prefecture Within Hitachi Construction Machinery Engineering Co., Ltd. (72) Yoshiaki Hirose 650, Kandamachi, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Engineering Inside the corporation

Claims (11)

[Claims] 1. A gripping means for gripping a casing pipe, a thrust cylinder capable of supporting and lowering the gripping means, a motor rotating the gripping means, and a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder. When excavating the ground with a casing pipe having a cutter bit at the tip using a casing driver provided with the casing driver, the cutter bit can be separated from the ground in a casing driver excavation control method that controls so as to prevent runaway of the casing pipe. A first step of extending the thrust cylinder so as to leave a stroke and gripping the casing pipe with the gripping means, and raising the casing pipe gripped by the gripping means by extending the thrust cylinder so as to separate the cutter bit from the ground. Together with the drive of the motor A second step of rotating the casing pipe up and rotating the casing pipe, and measuring at least the cylinder-side pressure of the cylinder-side pressure and the rod-side pressure of the thrust cylinder while rotating the casing pipe. And the third step of setting the set pressure of the relief valve so that the supporting force for supporting the gripping means does not fall below the thrust cylinder by the pressure on the cylinder side of the thrust cylinder. An excavation control method for a casing driver, wherein the ground is excavated by being pushed by a thrust cylinder while being rotated. 2. A gripping means for gripping a casing pipe, a thrust cylinder capable of supporting and lowering the gripping means, a motor rotating the gripping means, and a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder. When excavating the ground with a casing pipe having a cutter bit at the tip by using a casing driver provided with a casing pipe, the casing pipe gripped by gripping means is controlled by a casing driver excavation control method for controlling escape of the casing pipe. Is raised by extending the thrust cylinder so as to separate the cutter bit from the ground, and is rotated by driving a motor.
And at least the cylinder-side pressure and the rod-side pressure of the thrust cylinder are measured while the casing pipe is raised and rotated, and the self-sinking load obtained based on the measurement result is obtained. The second step of setting the set pressure of the relief valve so that the supporting force for supporting the gripping means does not fall below the pressure on the cylinder side of the thrust cylinder, and after releasing the gripping of the casing pipe by the gripping means, After passing through the third step of extending the thrust cylinder so that the casing pipe can be pushed in and gripping the casing pipe with the gripping means,
An excavation control method for a casing driver, wherein a ground is excavated by pushing a casing pipe with a thrust cylinder while rotating the casing pipe with a motor. 3. A gripping means for gripping a casing pipe, a thrust cylinder supporting the gripping means and capable of ascending and descending, a motor for rotating and driving the gripping means, and a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder. When excavating the ground with a casing pipe having a cutter bit at the tip, using a casing driver equipped with a casing driver, the pressure on the cylinder side of the thrust cylinder is controlled in a casing driver excavation control device that controls so as to prevent runaway of the casing pipe. And a thrust cylinder pressure measuring means for measuring at least the cylinder-side pressure of the rod-side pressure, and a casing driver control mechanism to which a measurement result of the thrust cylinder pressure by the pressure measuring means is inputted. Control of this casing driver The mechanism extends the thrust cylinder so as to separate the cutter bit from the ground and at the same time the self-sinking load obtained based on the measurement result of the thrust cylinder pressure measurement means measured with the motor rotated while the cylinder side of the thrust cylinder is And a control function of controlling a setting pressure of the relief valve so that a supporting force for supporting the gripping means does not fall below the pressure. 4. A gripping means for gripping a casing pipe, a thrust cylinder capable of supporting and lowering the gripping means, a hydraulic motor rotating the gripping means, and a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder. When excavating the ground with a casing pipe having a cutter bit at the tip using a casing driver having a, in the excavation control method of the casing driver that controls to prevent runaway of the casing pipe, the cutter bit is separated from the ground The first step of extending the thrust cylinder so as to leave the stroke to be obtained and gripping the casing pipe with the gripping means, and raising the casing pipe gripped by the gripping means by extending the thrust cylinder so as to separate the cutter bit from the ground. And hydraulic motor In the second step of rotating by driving, and while raising and rotating the casing pipe in this way, at least the cylinder side pressure and the cylinder side pressure of the thrust cylinder are measured on the cylinder side, and the measurement result is obtained. The settling pressure of the relief valve was set, and the casing pipe was raised and rotated so that the self-sinking load obtained based on the pressure on the cylinder side of the thrust cylinder did not fall below the supporting force for supporting the gripping means. A third step of measuring the driving pressure of the hydraulic motor in this state, obtaining a value relating to the rotational torque of the hydraulic motor based on the measurement result and measuring a value relating to the peripheral surface friction torque, and rotating the casing pipe with the hydraulic motor. While excavating the ground by pushing it with a thrust cylinder. Push the casing pipe with a thrust cylinder so that the sum of the set value to be set and the value related to the peripheral surface friction torque is close to the actual value related to the rotational torque of the hydraulic motor obtained based on the drive pressure of the hydraulic motor. The excavation control method of a casing driver, wherein the excavation of the ground performed by the casing pipe is controlled using the casing driver by the fourth step. 5. A gripping means for gripping a casing pipe, a thrust cylinder supporting the gripping means and capable of moving up and down, a hydraulic motor rotating the gripping means, and a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder. When excavating the ground with a casing pipe having a cutter bit at the tip using a casing driver provided with a casing driver, a casing gripped by gripping means is provided in a casing driver excavation control method for controlling escape of the casing pipe. The first step of raising the pipe by extending the thrust cylinder so as to separate the cutter bit from the ground, and rotating the pipe by driving the motor, and thus raising and rotating the casing pipe to the side of the cylinder side of the thrust cylinder. Pressure and rod side Of the pressure of the cylinder, the self-sinking load obtained based on the measurement result is adjusted so that the supporting force for supporting the gripping means does not fall below the cylinder-side pressure of the thrust cylinder. In addition to setting the set pressure, the drive pressure of the hydraulic motor is measured in a state where the casing pipe is raised and rotated, and a value related to the rotational torque of the hydraulic motor is determined based on the measurement result to determine a value related to the circumferential surface friction torque. A second step of measuring the value, and a third step of, after releasing the gripping of the casing pipe with the gripping means, extending the thrust cylinder so that the casing pipe can be pushed in and gripping the casing pipe with the gripping means, Excavating the ground by pushing the casing pipe with a thrust cylinder while rotating it with a hydraulic motor, The casing pipe has a relationship such that the actual value of the rotational torque of the hydraulic motor obtained based on the drive pressure of the hydraulic motor is close to the sum of the set value related to the set excavation torque and the value related to the circumferential friction torque. Controlling the excavation of the ground performed by the casing pipe using the casing driver by the fourth step of pushing the ground with the thrust cylinder. 6. The pushing speed of the casing pipe is controlled by adjusting the flow rate of the thrust cylinder on the rod side when the casing pipe is pushed in by the thrust cylinder in the fourth step. Or the excavation control method of the casing driver according to claim 5. 7. When the casing pipe is pushed in by the thrust cylinder in the fourth step, the pressure on the rod side of the thrust cylinder is adjusted to control the pushing force of the casing pipe. Or the excavation control method of the casing driver according to claim 5. 8. A gripping means for gripping a casing pipe, a thrust cylinder capable of supporting and lowering the gripping means, a hydraulic motor rotating the gripping means, and a relief valve capable of adjusting the pressure on the cylinder side of the thrust cylinder. When excavating the ground with a casing pipe having a cutter bit at the tip using a casing driver with a cutter driver, in a casing driver excavation control device that controls so as to prevent runaway of the casing pipe, the cutter bit is separated from the ground. A thrust cylinder pressure measuring means for measuring at least the cylinder side pressure of the thrust cylinder pressure and the rod side pressure, and a driving pressure of the hydraulic motor. Drive pressure measuring means and thrust cylinder pressure measuring means Valve setting means for setting the relief valve set pressure such that the supporting force for supporting the gripping means does not fall below the self-sinking load obtained based on the measurement result and the pressure on the cylinder side of the thrust cylinder. And a rotation torque calculation unit that receives a measurement result from the drive pressure measurement unit and calculates a value related to a rotation torque of the hydraulic motor when the hydraulic motor rotates based on the measurement result, and the cutter bit is separated from the ground. The sum of the value relating to the rotation torque of the hydraulic motor calculated by the rotation torque calculation means when the detection means detects the rotation torque and the set value relating to the preset excavation torque, the rotation torque when excavating the ground with the casing pipe. The thrust series is set so that the actual value related to the rotational torque of the hydraulic motor calculated by the calculating means is close to the actual value. Excavation control system for a casing driver, characterized in that a thrust cylinder control means for controlling driving of da. 9. The thrust cylinder control means for controlling the driving of the thrust cylinder, wherein the thrust cylinder rod side flow rate is adjusted to control the pushing speed of the casing pipe. An excavation control device for a casing driver as described in the above. 10. The thrust cylinder control means for controlling the driving of the thrust cylinder, wherein the pressure on the rod side of the thrust cylinder is adjusted to control the pushing force of the casing pipe. An excavation control device for a casing driver as described in the above. 11. A cutter bit is provided at the tip using a casing driver having gripping means for gripping a casing pipe, a thrust cylinder supporting the gripping means and capable of moving up and down, and a motor for rotating the gripping means. When holding the casing pipe with the holding means,
This is a method of measuring the self-subsidence load of a casing driver that measures the self-subsidence load acting on a thrust cylinder. In the first step of rotating the casing pipe in this manner, at least the cylinder-side pressure and the rod-side pressure of the thrust cylinder are measured while the casing pipe is rotated and raised. A second step of calculating a value relating to the self-subsidence load based on the self-subsidence load acting on the thrust cylinder.