JP2005068691A - Pile driver and its pile press fitting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pile driver for accurately finding an amount of press fitting per one pile rotation in a condition that pile pushing force is constant by facilitating operation making pushing force constant during pile press fitting, and to provide its pile press fitting method. <P>SOLUTION: The pile driver press fitting a pile (18) into ground to be buried in prescribed depth is provided with a controller (40) for automatically controlling a pile lowering speed so that the pushing force during pile press fitting is substantially constant. In addition, the pile driver is provided with a switch (67) enabling combination of a manual operation mode operating the pile lowering speed manually and a pushing force constant control mode automatically controlling the pile lowering speed for controlling the pushing force constant. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pile driving machine and a pile press-in method thereof.

  Conventionally, when the ground that is the foundation of a building does not have a supporting force that exceeds the specified value, it is common practice to embed piles such as steel pipe piles in the ground to reinforce the ground. In addition, a pile press-in method for press-fitting this steel pipe pile while ensuring a sufficient supporting force with respect to the ground is widely used. A pile driving machine used for burying such a pile usually has a crawler type traveling device and supports the buried pile so that it can move up and down at one end in the front-rear direction of the vehicle body. A leader that can be raised and lowered, and provided with a rotary drive unit having a hydraulic motor for rotating the pile, and a lift drive unit having a hydraulic motor for raising and lowering the rotary drive unit and applying pressure input to the pile. The head can be moved up and down.

  In the pile press-in method, the geological survey is conducted in advance to confirm the depth of the supporting ground layer, and the pile length to be buried is determined by this, and this pile length is buried by the pile driver. Yes. At this time, various construction management values have been proposed in order to confirm that the pile end has reached the supporting ground layer. For example, pressure input at the time of press-in burying completion (at the time of stopping), rotational torque at the time of press-in (see Patent Document 1), press-in amount per rotation of the pile when the pile pressing force (pressure input) is constant. Since there is a general relational expression between these management values and N values, pile construction is managed by monitoring the management values. Also, when rotary press-fitting winged piles, in order to press-fit at a substantially blade pitch, if the pressure input fluctuates, the pitch will be disturbed and sufficient support force will not be obtained. It is necessary to move the drive unit up and down.

  In addition, the said N value is generally used in order to represent the hardness of a ground, and is calculated | required by performing the dynamic penetration test of a pile. The dynamic penetration test is to drop a hammer with a predetermined weight from a predetermined height and drive a pile, measure the amount of settlement and rebound of the pile at this time, and determine the ultimate bearing capacity of the tip support pile from this measured value. This is an estimation test, and the number N of hits when the hammer rebounds is equivalently determined as the hardness of the ground.

Japanese Patent Laid-Open No. 10-280409 (page 2-3, FIG. 1)

  However, according to the operation method in the conventional pile driving machine described above, when the press-fitting amount per pile rotation under the condition that the pile pressing force is constant is used as a control value, the operator can make the pile pressing force constant. In addition, it is necessary to adjust the operation amount of the lifting operation lever while monitoring the pressure input value displayed on the monitor display. For this reason, the operator has to concentrate very much on the operation of the elevating operation lever, and it is necessary to correct the operation amount frequently, so that there is a problem that fatigue is increased both mentally and physically. . In addition, the pile pressing force is not constant depending on the operator's operation of the lifting operation lever, so it is difficult to accurately determine the amount of press-fitting per pile rotation.

  The present invention has been made paying attention to the above problems, and can easily perform an operation of making the pressing force constant at the time of press-fitting the pile. An object of the present invention is to provide a pile driving machine and a pile press-in method that can accurately determine the press-fit amount per pile rotation.

  In order to achieve the above object, according to a first invention, in a pile driving machine in which a pile is press-fitted into the ground and buried at a predetermined depth, the pile is automatically lowered so that the pressing force at the time of the pile press-in is substantially constant. The controller includes a controller that controls the speed.

  The second invention is a pile driving machine that presses a pile into the ground and embeds it at a predetermined depth, and a controller that automatically controls the pile lowering speed so that the pressing force at the time of pile press-in is substantially constant; A pressing force constant control start switch that enables a combination of a manual operation mode for manually controlling the pile lowering speed and a pressing force constant control mode for automatically controlling the pile lowering speed to perform a constant pressing force control. It has a configuration.

  Further, the third invention is the pile driving machine according to the first invention or the second invention, wherein the controller inputs again the speed operation command by the lifting operation lever even during the pressing force constant control by the pressing force constant control start switch. In such a case, the manual operation mode is given priority.

  Further, the fourth invention is a pile press-in method of a pile driving machine in which the pile is press-fitted into the ground and buried at a predetermined depth, so that when the pile is press-fitted, the pressing force at the time of press-fitting the pile is substantially constant. It is a method to control the pile lowering speed.

  According to the first invention, since the pressing force at the time of press-fitting piles is automatically controlled to be substantially constant, it is not necessary for the operator to operate the lifting operation lever to make the pressing force constant, and the operability is improved and the burden on the operator is improved. Since the variation in pressing force is small, the press-fitting amount per pile rotation, which is the construction control value, can be obtained with high accuracy. Quality can be improved.

  Further, according to the second invention, in addition to the same effects as the first invention, the manual lifting operation and the automatic lowering speed control by the constant pressing force control can be performed in combination. Alternatively, automatic control can be selected. Thereby, when the vicinity of the predetermined target depth is reached, it is possible to easily select the constant pressing force control when it is necessary to accurately measure the press-fitting amount per pile rotation as the construction management value, and the operability is good.

  Further, according to the third aspect of the invention, the manual operation mode can be set by simply operating the lifting / lowering operation lever during the pressing force constant control. Therefore, switching to the manual operation can be easily performed, and the operability is good.

  Further, according to the fourth invention, the pile pressing force is automatically controlled to be substantially constant and the pile is press-fitted, so that, as in the first invention, the operator's operation of the lifting operation lever for making the pressing force constant Is not necessary, and the operation becomes easier and the burden on the operator can be reduced. In addition, since the variation in the pressing force is reduced, the press-fitting amount per rotation of the pile, which is a construction management value, can be obtained with high accuracy, so that the construction quality can be improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, a schematic configuration of a pile press-fitting machine to which the present invention is applied will be described with reference to FIGS. 1 and 2. FIG. 1 is a side view of a pile press-fitting machine, and FIG. 2 is a front view thereof.

  1 and 2, the pile press-fitting machine 1 has an upper swing body 3 rotatably mounted at a substantially central portion of a lower travel body 2 provided with a travel device (in this example, a pair of left and right crawler type travel devices). doing. A driver's cab 4 is installed on the front left side of the upper swing body 3 and a counterweight 6 is attached to the rear end. In addition, a pile press-fitting device 5 is mounted on the mounting frame 12 provided at the center of the left and right of the front part of the upper swing body 3 in a vertical state (state during excavation) and a horizontal state (when moving during non-excavation and transportation). It is provided so as to be able to undulate between. Further, outriggers 7, 7, and 8 are provided on the left and right of the rear end portion of the upper swing body 3 and on the right side of the front end portion, respectively.

  The pile press-fitting device 5 includes a leader 11 attached to the mounting frame 12 so as to be able to move up and down, and an auger device 30 and a rotary press-fitting drive device 15 are provided on the left and right sides of the leader 11 so as to be movable up and down. ing. The auger device 30 and the rotary press-fitting drive device 15 are guided and supported by the reader 11 so as to be movable up and down.

  The rotary press-fitting drive device 15 includes a rotary motor 17 that rotates a pile 18 such as a steel pipe pile connected to a lower end connecting portion, and a lifting motor 21 that drives the case 16 up and down. Is attached. The rotary motor 17 and the lift motor 21 are constituted by hydraulic motors.

  The auger device 30 includes an auger drive unit 31 having a drive hydraulic motor (not shown) and an auger 32 attached to a lower end portion of the drive shaft of the auger drive unit 31.

Next, the rotary press-fitting drive device 15 will be described in detail with reference to FIGS. 3 and 4 are an X view of FIG. 2 and a Y view of FIG. 3, respectively.
3 and 4, a rotary motor 17 with a built-in speed reducer is attached to the lower part of the case 16 with the rotary shaft directed in the vertical direction, and the output shaft of the rotary motor 17 is attached to the lower end of the case 16. It is connected to a drive shaft 18a rotatably supported by a bearing 19 provided in the bearing box 19a. The buried pile is connected to the drive shaft 18a via a connecting portion (not shown). Further, an elevating motor 21 is mounted on the upper portion of the case 16 with its rotating shaft oriented in the horizontal direction, and a sprocket 24 is rotatably provided coaxially with a gear 23 meshed with a gear 22 provided on its output shaft. It has been. A chain 26 disposed along the longitudinal direction (vertical direction in the vertical state) of the leader 11 is engaged with the sprocket 24, and two pieces for adjusting the slackness of the chain 26 are engaged. Idle sprockets (or rollers) 25a and 25b are provided. The sprocket 24, the gear 23, and the idle sprockets 25a and 25b are rotatably supported by the case 16. At this time, the rotary press-fitting drive device 15 is moved up and down by rotating the sprocket 24 by the rotation of the lifting motor 21. Further, the rotation of the rotary motor 17 causes the pile connected to the connecting portion to rotate.

  On the outer peripheral surface of the bearing box 19a, a load cell as a pressure input detection sensor 65 for detecting a pile pressure input by the lifting motor 21, that is, a press-fitting load, is attached. An encoder that detects the number of revolutions of the lifting motor 21 is attached to the output shaft of the lifting motor 21 as its press-fit amount sensor 66.

Next, the configuration of the rotary press-fitting drive device 15 will be described based on the block circuit diagram shown in FIG.
The main pump 41 is connected to the input port of the raising / lowering switching valve 43 via the pipe line 51a, and the drain port of the raising / lowering switching valve 43 is connected to the tank 42 via the pipe line 51b. The output port of the raising / lowering switching valve 43 is connected to the raising / lowering motor 21 via the pipe lines 53a and 53b.

  The control port of the raising operation valve 46b of the pair of pilot pressure operation valves 46a, 46b connected to the raising / lowering operation lever 45 is connected to the pilot operation portion of the raising / lowering switching valve 43 in the raising direction operation portion. 55b, and the output port of the shuttle valve 44 is connected to the lower direction operation part via the pilot line 55a. The control port of the electromagnetic proportional operation valve 47 is connected to one input port of the shuttle valve 44 via a pilot line 54a, and the output of the electromagnetic switching valve 49 is connected to the other input port via a pilot line 54b. The port is connected. The control port of the lowering operation valve 46 a of the pair of pilot pressure operation valves 46 a and 46 b is connected to the input port of the electromagnetic switching valve 49.

  A pilot pressure pump 48 is connected to the input port of the pair of pilot pressure operation valves 46a and 46b via a pilot line 57a, and a tank is connected to the neutral port of the operation valves 46a and 46b via a pilot line 57b. 42 are connected to each other. The pilot pressure operation valves 46 a and 46 b output pilot pressure corresponding to the operation amount of the elevating operation lever 45.

  A pilot pressure pump 48 and a tank 42 are connected to an input port and a neutral port of the electromagnetic proportional operation valve 47 via pilot lines 58a and 58b, respectively. The drain port of the electromagnetic switching valve 49 is connected to the tank 42 via a pilot pipe line 58b.

  The main pump 41 is connected to the rotary motor 17 via a rotation switching valve (not shown). A control port of a pair of electromagnetic proportional operation valves (not shown) is connected to a pilot operation section of the rotation switching valve (not shown), and a controller of the pair of electromagnetic proportional operation valves is connected to a controller. An operation command signal from 40 is input.

  The pilot pipes 55b and 56 are provided with pressure sensors 61 and 62 for detecting pilot operating pressures of the raising and lowering operating valves 46b and 46a, respectively, and output signals from the pressure sensors 61 and 62 are sent to the controller 40. Have been entered. The pipes 53a and 53b connecting the elevating motor 21 and the elevating switching valve 43 are provided with pressure sensors 63 and 64 for detecting the load pressure of the elevating motor 21, and the output signals of the pressure sensors 63 and 64 are Input to the controller 40. Furthermore, the press-fitting amount sensor for detecting the output signal of the press-fitting detection sensor 65 for detecting the press input of the pile by the lifting motor 21 and its press-fitting amount (that is, corresponding to the depth, in this example, the number of rotations of the lifting motor 21). 66 output signals are input to the controller 40.

  A pressing force constant control start switch 67 is provided on the upper surface of the knob of the lifting operation lever 45, and an output signal of the switch 67 is input to the controller 40. The mounting position of the constant pressing force control start switch 67 is not limited to the upper surface portion of the knob of the lifting operation lever 45, and may be, for example, the front surface portion or the left and right side surfaces of the knob.

  The pile press-fitting machine 1 is provided with an operation panel 68. The operation panel 68 is provided with a data setting switch 68a such as a numeric keypad for presetting various data such as a control target value of the pile pressing force required for the pile press-in operation. Further, the operation panel 68 includes a rotary motor on / off switch 68b for operating forward / stop / reverse rotation of the rotary motor 17 of the pile press-fitting device 5, and the ground at the time of checking the setting data and pile press-fitting A display unit 68f is provided for monitoring the rigidity (details will be described later), control device internal information, and the like. The operation panel 68 and the controller 40 are connected by a data communication line for transmitting and receiving the various setting data and display data, and a signal line for inputting the switch signal to the controller 40.

Next, the operation of the configuration of the rotary press-fitting drive device 15 described above will be described.
When the raising / lowering operation lever 45 is operated to be raised, a pilot pressure corresponding to the operation amount is input from the raising operation valve 46b to the raising direction pilot operating portion of the raising / lowering switching valve 43 via the pilot line 55b. The elevator motor 21 is rotated in the head raising direction by switching the spool.

  When the elevating operation lever 45 is operated to be lowered, the pilot pressure corresponding to the operation amount is input from the lower operation valve 46 a to the input port of the electromagnetic switching valve 49 via the pilot pipe line 56. At this time, if a manual lowering operation unlock command is output from the controller 40 to the solenoid operating portion of the electromagnetic switching valve 49, the electromagnetic switching valve 49 is switched to the A position, and the pilot pipeline 56 is lowered. The operating pilot pressure is input to one input port of the shuttle valve 44 via the pilot pipe line 54b.

  In addition, the output pilot pressure of the electromagnetic proportional operation valve 47 corresponding to the lowering speed command from the controller 40 is input to the other input port of the shuttle valve 44 via the pilot line 54a. The shuttle valve 44 outputs the larger one of the pilot pressures of both the input ports, and the pilot pressure is input to the lower direction pilot operation portion of the up / down switching valve 43 through the pilot line 55a. Normally, when a manual lowering operation unlock command is output from the controller 40 to the electromagnetic switching valve 49, the lowering speed command to the electromagnetic proportional operation valve 47 is zero speed, and therefore the shuttle valve 44 is used as a lowering pilot. The operation pilot pressure from the pressure operation valve 46a is output.

  The elevating switching valve 43 switches the spool position in accordance with the pilot pressure applied to the pilot operating section in the raising direction or the lowering direction, and controls the rotation speed of the elevating motor 21.

  On the other hand, when the manual lowering operation lock command is output from the controller 40, the electromagnetic switching valve 49 is switched to the B position, and the pilot oil in the pilot line 54b is drained to the tank 42 via the pilot line 58b. To do. At this time, since a predetermined lowering speed command is output from the controller 40 to the electromagnetic proportional operation valve 47, the output pilot pressure of the electromagnetic proportional operation valve 47 corresponding to the lowering speed command is supplied from the shuttle valve 44 to the pilot line. This is input to the pilot operating portion in the lowering direction of the elevation switching valve 43 via 55a. Thus, the controller 40 controls the rotational speed of the lifting motor 21 in the lowering direction.

Below, based on the flowchart shown in FIG. 6, the processing procedure of the pile press-in method according to the present invention will be described.
First, in step S1, the operator operates the rotary motor on / off switch to rotate the rotary motor 17 at a predetermined rotational speed. In step S2, the operator operates the lifting operation lever 45 to rotate the lifting motor 21 in the downward direction. At this time, a manual lowering operation unlock command is output from the controller 40 to the solenoid operating portion of the electromagnetic switching valve 49, and the electromagnetic switching valve 49 is switched to the A position and the electromagnetic proportional operation valve 47. The zero speed is output as the speed-down command to. Thereby, the shuttle valve 44 outputs the operation pilot pressure from the lowering operation valve 46 a corresponding to the lowering operation amount of the lifting operation lever 45 to the lifting switching valve 43.

  Next, in step S3, the controller 40 takes in the press-fitting amount detected by the press-fitting amount sensor 66 and measures the pile driving depth, and displays it on the display unit 68f of the operation panel 68. Then, the operator looks at the depth display value of the display unit, determines whether the driving depth of the pile has reached the target predetermined depth, and repeats the processing from step S1 until the predetermined depth is reached. When the predetermined depth is reached, the process proceeds to step S5. In step S5, the controller 40 checks whether the operator has turned on the constant pressing force control start switch 67, and if not, if the manual lowering operation lock command has been output in step S6, the manual lowering operation is performed. An unlock command is output to prioritize manual operation, and the process returns to step S1.

  When the pressing force constant control start switch 67 is turned on in step S5, the controller 40 outputs a manual lowering operation lock command to the electromagnetic switching valve 49 and switches the electromagnetic switching valve 49 to the B position in step S11. Next, in step S12, a predetermined lowering speed command of the lifting motor 21 is output to the electromagnetic proportional operation valve 47. Thus, the pilot pressure corresponding to the predetermined lowering speed command is output from the shuttle valve 44 to the elevating switching valve 43, and the speed of the elevating motor 21 is automatically controlled.

  Thereafter, in step S13, the controller 40 takes in the pressure input value detected by the pressure input detection sensor 65, and obtains a deviation value α from a preset target pressure input. Next, in step S14, the controller 40 obtains a command correction value according to the magnitude and sign of the deviation value α so that the deviation value α is small, and corrects the lowering speed command with the obtained command correction value. Output. At this time, a correction value corresponding to the differential pressure between the detected pressure values of the pressure sensors 63 and 64 may be further added. Thereafter, in step S15, the controller 40 checks whether the lifting operation lever 45 has once returned to neutral and operated again based on the detected pressure values of the pressure sensors 62 and 61, and if it is operated again, the controller 40 proceeds to step S6. The process is shifted to give priority to manual operation, and when it is not operated again, the process shifts to step S5 to repeat the process.

  When the pressing force constant control start switch 67 is turned on after the predetermined depth is reached by the above processing, the pile pressing force (pressure input) is automatically operated until the lifting operation lever 45 returns to neutral and is operated again. ) Is kept constant at a predetermined target value. For this reason, the amount of press-fitting per pile rotation at the time of pile press-in can be obtained with high accuracy, and the quality of pile embedding construction can be improved.

  In the above embodiment, the pile pressing force constant control mode is selected by the pressing force constant control start switch 67. However, the mode selection is not limited to this switch and the pressing force constant control mode or the manual operation mode is selected. It may be performed by a switch. In addition, switching from the pile pressing force constant control mode to the manual operation mode is performed by operating the elevating operation lever 45, but the present invention is not limited to this, and mode selection for selecting the pressing force constant control mode or the manual operation mode is similar to the above. It may be performed by a switch.

  Further, in the above embodiment, the method of switching from the manual operation mode to the constant pressing force control mode when the vicinity of the target depth is reached has been described as an example, but the present invention is not limited to this, and the entire press-fitting process is performed. Pile press-fitting may be performed in the pressing force constant control mode. Further, when switching to the constant pressing force control mode, safety can be improved by restricting the pressure input detection sensor 65 so that it cannot be switched when no load is applied.

  Also, the reaction force during pile press-in is obtained by fixing and supporting the vehicle body with the three outriggers 7, 7, 8. When a larger press-in reaction force is required, the auger 32 is attached before the pile press-in. It is possible to rotate and insert the ground into a predetermined depth and use the biting force of the auger 32 as a press-fitting reaction force.

  As an example of the pile press-fitting machine, the upper swing body 3 is turnably mounted on the lower traveling body 2, but the upper vehicle body provided with the pile press-fitting device may not be turnable.

The present invention has the following effects.
When the pile is press-fitted to the target depth, control to press-fit the pile with the pressure input (pressing force) substantially constant near the target depth is automatically performed, so there is no need for the operator to operate the lifting operation lever 45 Therefore, the operability can be improved and the press-fitting amount per pile rotation at the time of the pile press-fitting can be obtained with high accuracy because the press input is accurately controlled to the target value.

  Further, since the pressing force control can be selectively combined with a method of performing manual operation and a method of performing automatic control, manual operation or automatic control can be selected when necessary by the operator's judgment. Thereby, when the vicinity of the predetermined target depth is reached, it is possible to easily select when the press-fitting amount per pile rotation needs to be measured with high accuracy, and the operability is good.

  When the operator turns on the pressing force constant control start switch 67, the pressing force constant control is automatically performed, and the lifting operation lever 45 is operated again during this pressing force automatic control (that is, once returned to neutral). Then, the manual operation becomes effective by operating again), so that the manual operation and the automatic control switching operation are very simple and the operability is good.

  Since the pressing force constant control start switch 67 (that is, the pressing force constant control mode selection switch) is provided on the lifting operation lever 45, it is possible to easily switch between the pressing force constant control mode and the manual operation mode while holding the lifting operation lever 45. Good operability.

  As an application field of the present invention, there is a machine for burying not only a steel pipe pile but also a pile such as a concrete pile.

It is a side view of a pile press-fitting machine to which the present invention is applied. It is a front view of a pile press-fit machine to which the present invention is applied. FIG. 3 is an X view of FIG. 2. FIG. 4 is a Y view of FIG. 3. It is a block circuit diagram concerning the present invention. It is a flowchart showing the process sequence of the pile press-in method which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Pile press-fit machine, 2 ... Lower traveling body, 3 ... Upper turning body, 4 ... Operation room, 5 ... Pile press-fit apparatus, 6 ... Counterweight, 7, 8 ... Outrigger, 11 ... Leader, 15 ... Rotary press-fit drive device , 16 ... Case, 17 ... Rotation motor, 18 ... Pile, 18a ... Drive shaft, 19 ... Bearing, 19a ... Bearing box, 21 ... Lifting motor, 22, 23 ... Gear, 24 ... Sprocket, 26 ... Chain, 30 ... Auger Device 31 ... Auger drive unit 32 ... Auger 40 ... Controller 41 ... Main pump 42 ... Tank 43 ... Raising / lowering switching valve 44 ... Shuttle valve 45 ... Elevating operation lever 46a, 46b ... Pilot pressure operation Valve: 47 ... Proportional solenoid operated valve, 48 ... Pilot pressure pump, 49 ... Electromagnetic switching valve, 50 ..., 51a, 51b, 53a, 53b ... Pipe line, 54a, 54b, 5a, 55b, 56, 57a, 57b, 58a, 58b ... pilot pipe, 61, 62, 63, 64 ... pressure sensor, 65 ... pressure input detection sensor, 66 ... press-fitting amount sensor, 67 ... pressing force constant control start switch 68 ... Operation panel, 68a ... Data setting switch, 68b ... Rotary motor on / off switch, 68f ... Display section.

Claims (4)

In the pile driving machine that press-fits the pile (18) into the ground and embeds it at a predetermined depth,
A pile driving machine comprising a controller (40) that automatically controls the pile lowering speed so that the pressing force during pile press-in is substantially constant. In the pile driving machine that presses the pile (18) into the ground and embeds it at a predetermined depth,
A controller (40) that automatically controls the pile lowering speed so that the pressing force during pile press-in becomes substantially constant;
Pushing force constant control start switch (67) that enables a combination of manual operation mode for manually controlling the pile lowering speed and pressing force constant control mode for automatically controlling the pile lowering speed for constant pressing force control (67) A pile driver characterized by comprising In the pile driver according to claim 1 or 2,
The controller (40) gives priority to the manual operation mode when the speed operation command of the lifting operation lever (45) is input again even during the constant pressing force control by the pressing force constant control start switch (67). A featured pile driver. In the pile press-in method of the pile driver that press-fits the pile (18) into the ground and embeds it at a predetermined depth,
A pile press-in method for a pile driving machine, wherein when the pile (18) is press-fitted, the pile lowering speed is automatically controlled so that the pressing force at the time of the pile press-in is substantially constant.