JP2002121995A - Dynamic pressing method and vibration generator used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dynamic pressing method being actually applicable to construction work and a vibration generator for use in the method, being small and providing good controllability and workability. SOLUTION: A hollow, cylindrical piston 13 is fitted into a clearance formed between an end outer cylinder 11 and an end inner cylinder 12, in such a way that the piston can be excited in a direction parallel to propulsion direction D1 at a predetermined vibrational frequency, predetermined amplitude of displacement, and predetermined load amplitude. An end head 17 for imparting vibration to the ground is attached to an end along the propulsion direction D1 of the end head 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dynamic press-fitting method in which a tunnel such as a horizontal hole or a vertical hole can be constructed in the ground by imparting axial vibration to the ground like a pile driver. The present invention relates to a method and a vibration generator used in the method.

[0002]

2. Description of the Related Art As a method of burying a pipe in the ground, a static press-in method in which a tip device is simply pressed by a main pushing device installed in a shaft and the soil is pressed into the ground without excavating soil, An excavation method for excavating soil with an excavator and propelling the excavator in the ground while excavating the excavated soil, as shown in FIGS. 9 and 10 of the present application. The vibrator a is actuated to excite the front part c of the vibration generator b, and at the same time, the soil d around the vibration generator b is vibrated and fluidized, and the original pushing device f installed in the shaft e There is a dynamic press-in method in which the vibration generator b is press-fitted without excavating the soil by pressing.

[0003]

As described above, the static press-fitting method is a method in which the tip device is pushed by the main pushing device. Therefore, when the soil is hard soil or the pipe diameter is large,
The propulsion resistance at the time of press-fitting is increased, and applicable soil quality is limited to a soft place having an N value of about 15 or less, and applicable pipe diameter is also limited to a small diameter pipe of about 350 mmφ or less. Also, even when the static press-fitting method can be applied, the propulsion speed is slow with hard soil, so the construction period is long and the construction cost is high, and when the propulsion length is long, the total propulsion resistance is large and press-fitting can be performed. There is a problem that the propulsion length is limited because it disappears.

The excavation method can be applied to places where the static press-in method cannot be applied. However, since a soil excavation mechanism and an earth discharging mechanism are required, the equipment cost of the tip device becomes high, There are problems such as the necessity of disposal of the earth removal, the propulsion speed is low due to the excavation type, and the construction cost is high as a result.

In the case of the dynamic press-in method shown in FIGS. 9 and 10, there is a possibility that the problems of the static press-in method and the excavation method can be solved. There is no specific description as to whether or not to apply, so it is difficult to actually use it for construction.
Is a structure housed in the vibration generator b as an independent device, the outer diameter of the vibration generator b becomes large, and there is a possibility that the size of the apparatus may be increased.

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention provides a dynamic press-fitting method which can be actually applied to construction work, has a small apparatus, and has good operability and workability, and a vibration generating apparatus used in the method. It is done for the purpose of doing.

[0007]

According to a first aspect of the present invention, there is provided a dynamic press-fitting method according to the first aspect of the present invention, in which a tip head attached to a tip of a piston in a propulsion direction is vibrated in the ground in a direction parallel to the propulsion direction. And pushes the piston underground in the direction of propulsion.

According to a second aspect of the present invention, there is provided a dynamic press-fitting method in which the piston is vibrated in a direction parallel to the propulsion direction at at least one of a predetermined vibration frequency, displacement amplitude, and load amplitude.

According to a third aspect of the present invention, there is provided a vibration generating device, wherein a piston is fitted into a gap formed between a distal end outer cylinder and a distal end inner cylinder so as to be able to vibrate in a direction parallel to a propulsion direction. At the tip of the piston in the propulsion direction, a tip head for applying vibration to the ground is attached.

According to a fourth aspect of the present invention, the stroke in the direction parallel to the propulsion direction of the piston is formed larger than the amplitude when the piston is vibrated, and the piston is made larger than the amplitude when the piston is vibrated. By moving the piston, the piston can be used as a sub-propulsion mechanism of the device.

According to a fifth aspect of the present invention, there is provided a vibration generating apparatus, wherein a nozzle means for supplying a sliding material along the front surface of the head is provided on the front surface of the head.

According to a sixth aspect of the present invention, there is provided a vibration generator for detecting a stroke of a piston, a tip head or an acceleration of a piston in the vibration generator itself to detect a vibration state of the piston. At least one of an acceleration detector, a pressure detector for detecting a pressure of a fluid for operating the piston forward in the propulsion direction, and an earth pressure detector for detecting an earth pressure acting on the tip of the piston. Is provided.

According to a seventh aspect of the present invention, there is provided the vibration generating apparatus according to the first aspect, wherein at least one of the stroke of the piston, the acceleration of the head or the piston, the pressure of the fluid, and the earth pressure detected and fed back by each detector. At least one of the vibration frequency, displacement amplitude, load amplitude, and acceleration of the head can be controlled.

A vibration generating device according to an eighth aspect of the present invention is a device for a hydraulic circuit for operating a piston in the hollow portion of the hollow rear cylinder connected to the distal end outer cylinder or the distal end inner cylinder. And at least equipment for a hydraulic circuit for operating the piston among the equipment for control.

According to a ninth aspect of the present invention, there is provided a vibration generating device for preventing the piston from rotating in the circumferential direction between the distal end inner cylinder and the piston or between the distal end outer cylinder and the piston. A stop member is provided.

According to the present invention, it is possible to provide an inexpensive compact vibration generator which is applicable to a dynamic press-fitting method for applying vibration in the direction of propulsion underground and which has good operability and workability. Therefore, the work of laying the small-diameter pipe can be performed easily and efficiently.

In the case of claim 4, since the vibration generating device can be used as a sub-propulsion mechanism of the main pushing device, it is easy to cope with the dynamic press-fitting method. The press-fitting of the tip device can be performed more smoothly.

In the case of claim 6, the excited state of the tip head can be detected easily and quickly, and in the case of claim 7, the excited state of the tip head can be controlled easily and reliably.

In the case of claim 8, the responsiveness of the hydraulic pressure is improved, and in the case of claim 9, since the piston does not rotate in the circumferential direction, the wiring or piping housed in the hollow portion of the piston is provided. No twisting occurs.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 8 show an example of an embodiment of the present invention. A pipe burying device to which the tip device of the present invention is applied is shown in FIG. 8, in which 1 is a tip device. The tip device 1 can apply vibration to the underground soil 3 by exciting the tip head 2 in the axial direction parallel to the propulsion direction D1.
A direction correcting device 6 comprising a vibration generating device 4 located on the forward side of the propulsion direction D1 and a bending mechanism 5 connected to the rear of the vibration generating device 4 in the propulsion direction D1 and for correcting the propulsion direction D1 during propulsion. It has.

Reference numeral 7 denotes an insertion tube disposed behind the direction correcting device 6 in the propulsion direction D1 of the tip device 1. Reference numeral 8 denotes a rear end of the insertion tube 7 which is disposed in a vertical shaft 9 and is pressed via a pressing plate 10. It is a main pushing device such as a jack.

In the pipe burying device, the soil 3 is fluidized by applying vibration to the soil 3 by vibrating the head 2 of the vibration generating device 4 in a direction parallel to the propulsion direction D1. Then, the original pushing device 8 is extended and the insertion tube 7 is pressed into the ground via the pressing plate 10, and the tip device 1 is inserted by the insertion tube 7.
Is pressed to propel the distal end device 1. When the soil 3 is fluidized, the shearing force is reduced, and the thrust resistance applied to the front surface of the tip device is reduced, so that the tip device 1 can be easily pressed into the ground.

The details of the vibration generator 4 are shown in FIGS. 1 to 3. In the drawings, reference numeral 11 denotes a cylindrical distal end outer cylinder. In the distal end outer cylinder 11, a cylindrical distal end inner cylinder 12 is formed such that a gap is formed at a predetermined interval between the distal end outer cylinder 11 and the inner periphery of the distal end outer cylinder 11 in a portion other than the rear part in the propulsion direction D1. Are inserted concentrically, and the propulsion direction D of the distal end inner cylinder 12 is
One rear end is fitted and fixed in a mounting hole formed in the rear end of the distal end outer cylinder 11 in the propulsion direction D1. Tip inner cylinder 1
2 is shorter than the distal end outer cylinder 11 in the direction parallel to the propulsion direction D1.
1 is located within.

In the gap between the distal end outer cylinder 11 and the distal end inner cylinder 12, the outer periphery slides with respect to the inner periphery of the distal end outer cylinder 11, and the inner periphery slides with respect to the outer periphery of the distal end inner cylinder 12. The piston 13 is fitted so that it can reciprocate in the propulsion direction D1. The distal end of the piston 13 in the propulsion direction D1 projects forward from the distal end outer cylinder 11 in the propulsion direction D1. I have. Thus, the distal end outer cylinder 11 and the distal end inner cylinder 12
The piston 13 also serves as a structure of the vibration generator 4.

An oil chamber 14 is formed in an inner peripheral rear portion of the distal end outer cylinder 11, an outer peripheral halfway of the distal end inner cylinder 12, and a gap surrounded by the rear end of the piston 13. An oil chamber 15 is formed in a gap surrounded by the peripheral step and the outer peripheral step on the distal end side of the distal end inner cylinder 12. An oil passage 11 having a front end opening to the oil chamber 14 and a rear end opening to the rear surface of the front end outer cylinder 11 is provided in the front end outer cylinder 11.
In the front end inner cylinder 12, an oil passage 12a having a front end opening to the oil chamber 15 and a rear end opening to the rear surface of the front end inner cylinder 12 is formed.

A distal end of the piston 13 projecting forward from the outer cylinder 11 in the propulsion direction D1 is provided with a hollow disk-shaped seat 16.
Is attached, and a tip head 17 of the vibration generator 4 is attached to the tip of the seat 16 in the propulsion direction D1 so as to be replaceable. In the illustrated example, the tip head 17 is in the propulsion direction D1.
The shape is a frusto-conical shape tapered forward, but may be a flat shape instead of an umbrella shape depending on the soil quality of the soil into which the tip device 1 is pressed. Thus, oil chamber 1
By supplying / discharging oil to / from the nozzles 4 and 15, the tip head 17 is reciprocated and vibrated in a direction parallel to the propulsion direction D1 via the piston 13, so that vibration can be applied to the soil. The tip head 17 has the same structure as the tip head 2,
Although the outer diameter is formed slightly larger than the outer diameter of the distal end barrel 11, this is done so that excessive resistance does not act on the distal end barrel 11 when the distal end device 1 is press-fitted. In order to

In the inner space of the distal end inner cylinder 12, a detector component 18a fixed to the inner space and a detector component 1 attached to a bracket 19 supported on the seat 16 side are provided.
8b, a magnetic force type stroke detector 18 which is capable of detecting the amount of displacement of the piston 13 in the propulsion direction D1 is provided so as to be located at the axial center position of the piston 13.

A plurality of lubricating materials for supplying lubricating materials such as bentonite discharged radially outward of the distal head 17 along the tapered surface to the underground soil are provided on the tapered surface of the distal head 17. The nozzles 20 are provided at regular intervals in the circumferential direction, and a lubricant supply pipe 21 is connected to the lubricant supply nozzle 20. Also, at the axial center of the tip of the tip head 17,
An earth pressure detector 22 for detecting earth pressure when the tip device 1 is press-fitted is attached, and an internal space of the tip head 17 is used to detect acceleration when the tip head 17 is vibrated. Are disposed.

At the rear end of the outer cylinder 11 in the propulsion direction D1 is formed concentric with the outer cylinder 11 at substantially the same outer diameter, and a lid 24 is attached to the rear end of the outer cylinder 11 in the propulsion direction D1. The connected hollow rear cylinder 25 is connected to the rear cylinder 25.
In the hollow portion, various devices of a hydraulic circuit and various devices of a control system necessary for vibrating the tip head 17 in a direction parallel to the propulsion direction D1 are accommodated.

The devices housed in the rear cylinder 25 are a servo-type electromagnetic control valve 26 constituting a hydraulic circuit, accumulators 27 and 28, and a stroke detector 1 in a control system.
8, an amplifier for the acceleration detector 23, a wiring-saving unit, and the like. The oil passages 11a and 12a are connected to the pipeline 2
The pipes 29 and 30 extend rearward in the propulsion direction D1 of the tip device 1 through the rear cylinder 25, and the pipes 29 and 30 are connected to a servo-type electromagnetic control valve. 26
It is connected to the. Further, the rear ends of pipes 51 and 53 in FIG. 4 described later connected to the electromagnetic control valve 26 are connected to couplers 31 and 32 attached to the lid 24, and the pipe 30 is located in the middle of the pipe 51. It is connected to the.

The pipe 30 may be connected to the electromagnetic control valve 26 as shown by a virtual line in FIG.

The tip of a pipe 33 is connected to the lubricating material supply nozzle 20, and the pipe 33 is connected to the piston 13 and the tip inner cylinder 1.
2 and a rear end extending through each hollow portion of the rear cylinder 25, and a rear end thereof merges and is connected to a coupler 34 attached to the lid 24.

In FIG. 1 and FIG. 3, reference numeral 35 designates the inside of the piston 13 so that it can be guided by the guide means 12b having a channel-like cross section fixed to the distal end of the distal end inner cylinder 12 so as to extend parallel to the propulsion direction D1. A key-shaped detent member protruding from the circumference prevents the piston 13 from rotating in the circumferential direction when the piston 13 moves back and forth in a direction parallel to the propulsion direction D1.

A hydraulic circuit diagram for vibrating or advancing the head 17 via the piston 13 is shown in FIG. 4, in which reference numeral 36 denotes a hydraulic unit, and 37 denotes a hydraulic circuit for vibration.

The hydraulic unit 36 is installed on the ground, and on the discharge side of a hydraulic pump 39 driven by an electric motor 38, a check valve 40 and a check valve 47 with a variable throttle are provided in the middle.
Further, a pipe 42 to which the coupler 41 is connected is connected to the tip of the oil flow direction D2. The hydraulic unit 36 has a return line 45 connected to the coupler 43 at the rear end in the oil flow direction D2 and returning the oil to the tank 44. The hydraulic pump 39 is supplied with the oil sucked from the tank 44. The supplied suction line 46 is connected.

On the downstream side of the check valve 40 in the oil flow direction D2 in the pipe 42, a switching valve 48 is connected in the middle and one end of a pipe 49 connected to the return pipe 45 at one end is connected to the other end. It is connected. 50 of the devices of the hydraulic unit 36 are safety valves.

Each component of the hydraulic circuit 37 is housed in the rear cylinder 25, and a pipe 52 is provided at the rear end of a pipe 51 whose leading end in the oil flow direction D2 is connected to the electromagnetic control valve 26. The coupler 31 is connected to the coupler 41 of the hydraulic unit 36 through the intermediary of the coupler 31. Also, pipe 51
The accumulator 27 for compensating the pressure of the oil supplied to the oil chambers 14 and 15 is connected downstream of the accumulator 27 connection position in the oil flow direction D2.

At the end of a return pipe 53 whose rear end in the oil flow direction D2 is connected to the electromagnetic control valve 26, a coupler 32 adapted to be connected to the coupler 43 of the hydraulic unit 36 via a return pipe 54. The accumulator 28 for preventing pulsation of the oil flowing through the return line 53 is connected to a halfway portion of the connected return line 53.

A safety valve 55 is connected to a line 64 connecting a portion of the line 51 upstream of the accumulator 27 in the oil flow direction D2 and an intermediate portion of the return line 53, and a halfway portion of the line 29. A safety valve 57 is connected to a pipe 56 connected upstream of the accumulator 28 connection part of the return pipe 53 with respect to the oil flow direction D2. In the hydraulic circuit 37, reference numeral 58 denotes a drain tank installed in the rear cylinder 25 so as to receive oil leaked from a seal portion (not shown).

FIG. 5 shows a control device when the tip head 17 is vibrated through the piston 13, and the earth pressure P acting on the tip head 17 is detected by the earth pressure detector 22.
1. Acceleration α at the time of excitation of the tip head 17 detected by the acceleration detector 23, displacement amount L of the piston 13 detected by the stroke detector 18 in a direction parallel to the propulsion direction D1 of the tip head 17, and a pressure detector The oil pressure P2 in the oil chamber 14 detected at 59 is used as a detection signal as a detection signal for the controller 6 installed on the ground.
0 can be given to the arithmetic control unit 61.

The vibration frequency fo when the tip head 17 is excited, the displacement Lo when the tip head 17 is excited,
The displacement amplitude Ca, the thrust F (load W) when the tip device 1 is pressed into the ground, and the load amplitude Wa are calculated by the host controller 62 or an operator such as a CPU as an excitation condition. The control mode switching command C1 and other operation commands C2 can also be given to the arithmetic and control unit 61 of the control device 60. Further, the operation control unit 61 of the control device 60 can supply the operation state information I to the host system control device 62.

Further, a switching command V can be given to the electromagnetic control valve 26 from the arithmetic control unit 61 in the control device 60 based on various data given from the host system control device 62 and the like. In FIG. 5, reference numeral 63 denotes a display unit for displaying operation state data from the arithmetic and control unit 61 in the control device 60.

Next, the operation of the illustrated example will be described with reference to FIGS. Advanced device 1 provided with vibration generating device 4
When the piston 13 is dynamically press-fitted, the piston 13 is stopped at the neutral position in the middle of the maximum stroke, and FIG.
The safety valves 55 and 57 of the hydraulic circuit 37 shown in FIG.
Is set as PO1 and the set pressure of the safety valve 57 is set as PO2, the pressure is adjusted so that PO1> PO2.

In the hydraulic unit 36, the hydraulic pump 39 is driven by the electric motor 38 in a state where the switching valve 48 is switched so that the oil flows, and the oil discharged from the hydraulic pump 39 is supplied to the pipeline 42, 49, switching valve 48, return line 4
5 to a tank 44.

Further, from the host system control device 62, the vibration frequency fo, the displacement Lo, the displacement amplitude Ca,
Thrust F (load W) generated in the tip head 17, load amplitude Wa, control mode switching command C1, and other operation commands C
2 etc. are given to the arithmetic and control unit 61 in the control device 60. Therefore, by turning on the operation button for starting operation, a switching command is given from the arithmetic control unit 61 of the control device 60 to the switching valve 48 of the hydraulic unit 36, and the oil in the pipeline 49 passes through the switching valve 48. Not to switch,
At a time interval determined by the vibration frequency fo, the electromagnetic control valve 26
, And the electromagnetic control valve 26 switches alternately so that the pipes 51 and 29 communicate with each other or the pipe 29 and the return pipe 53 communicate with each other.

Therefore, in the electromagnetic control valve 26, the line 5
When switching is made such that the first and second fluids communicate with each other, the oil discharged from the hydraulic pump 39 passes through the electromagnetic control valve 26 via the pipes 42, 52, and 51, and passes from the pipe 29 via the oil passage 11a. The oil is introduced into the oil chamber 14, and the oil in the oil chamber 15 is discharged.
6. Circulate to the oil chamber 14 through the pipe line 29 and the oil line 11a.
Therefore, the piston 13 advances by a predetermined amount in the propulsion direction D1.

When the electromagnetic control valve 26 is switched so that the line 29 and the return line 53 communicate with each other, the oil discharged from the hydraulic pump 39 is supplied to the lines 42, 52, 51.
Through the pipe 30, the oil is introduced into the oil chamber 15 through the oil path 12a, and the oil in the oil chamber 14 is supplied from the oil path 11a to the pipe 29,
It returns to the tank 44 via the electromagnetic control valve 26 and the return lines 53, 54, 45. Therefore, the piston 13 moves backward by a predetermined amount in the direction opposite to the propulsion direction D1.

By reciprocating the piston 13 in a direction parallel to the propulsion direction D1 with a predetermined vibration frequency, amplitude, and thrust, the tip head 17 moves in a direction parallel to the propulsion direction D1 under the above-described conditions. Vibration is applied to the soil around the distal end head 17 by the vibration of the distal end head 17. For this reason, when the soil fluidizes and the shear resistance decreases, as a result, when the leading end device 1 shown in FIG.
The tip device 1 is easily, reliably, and quickly pressed into the soil to form a tunnel by the tip device 1, and the insertion tube 7 is similarly easily, reliably, and quickly laid.

At the time of this vibration and press-fitting, the sliding material is fed through the sliding material supply pipe 21 and is fed from the sliding material supply nozzle 20 to the tip head 1.
7 is jetted along the tapered surface of the tip head 17. For this reason, the fluidity of the soil on the front surface of the tip head 17 is improved, and the press-fitting of the tip device 1 is performed more smoothly.

If the piston 13 is advanced by the full stroke, it can be used not only to vibrate the tip head 17 but also as a sub-propulsion mechanism instead of the original pushing device 8.

When the tip device 1 is press-fitted, the displacement amount L of the piston 13 and the tip head 17 is detected by the stroke detector 18, and the earth pressure P 1 acting on the front surface of the tip head 17 is detected by the earth pressure detector 22. Further, the acceleration detector 23
, The acceleration α of the tip head 17 at the time of reciprocating vibration, and the oil pressure P2 in the oil chamber 14 by the pressure detector 59.
Are respectively detected, and the arithmetic and control unit 6 in the control device 60 is
1, a predetermined calculation is performed, and the electromagnetic control valve 2
6 is controlled to a predetermined state.

Therefore, the vibration frequency fo, the displacement Lo, the displacement amplitude Ca, the thrust F (load W), and the load amplitude Wa of the piston 13 at the time of the excitation are arbitrarily set, and the tip is determined on the basis of the aforementioned detection data. The press-fitting of the tip device 1 can be performed while controlling the amplitude at the time of the vibration of the head 17 and the thrust applied to the tip head 17 to a predetermined state set in advance. Feedback control is employed as the control.

FIG. 6 shows the relationship between the time and the displacement L of the tip head 17 actually generated by the control of the illustrated example. FIG. 7 shows the relationship actually generated by the control of the illustrated example.
Time and thrust Fr acting on piston 13 (tip head 1
7 is shown in FIG.

In the illustrated example, the distal end outer cylinder 11, the distal end inner cylinder 12, and the piston 13 also serve as the structure of the distal end device 1, so that the load resistance is large and the area of the oil chamber 14 can be widened. Even if a large static front resistance acts on the tip head 17 having the same diameter as the outer cylinder 11, a sufficiently large thrust to overcome the front resistance can be generated.

Since the distal end inner cylinder 12 and the piston 13 have a hollow cylindrical shape, the hollow portion can be used as a space for passing wiring and piping. Since the detent member 35 is provided, the piston 13 does not rotate with respect to the distal end outer cylinder 11 and the distal end inner cylinder 12, and therefore, there is no occurrence of twisting in the wiring and piping housed in the hollow portion. .

In the illustrated example, the vibration frequency fo, the displacement Lo, the displacement amplitude Ca, the thrust F (load W),
In order to control the load amplitude Wa to an arbitrarily set state,
Various control devices are provided as shown in FIG.
Reliable and reliable press-fitting work can be performed.

Since a solenoid control valve 26 and accumulators 27 and 28 are accommodated as hydraulic equipment in a rear cylinder 25 connected to the rear of the distal end outer cylinder 11, the oil chamber 14,
The responsiveness of the switching of the oil introduced into the nozzle 15 is improved, and the amplitude when the tip head 17 is vibrated can be easily changed.

Further, at the time of press-fitting, the lubricating material is supplied into the soil from the lubricating material supply nozzle 20 provided on the tip head 17, so that the fluidity of the soil is improved.

Further, since the position of the piston 13 in the direction parallel to the propulsion direction D1 can be controlled,
3 can be used as a propulsion mechanism similarly to the main pushing device 8.

According to the illustrated example, it is possible to provide a small-sized vibration generator which is practically applicable to the dynamic construction method and has good operability and workability at a low cost. Can be performed easily and efficiently.

The embodiments of the present invention are not limited to the above-described examples, but various changes can be made without departing from the scope of the present invention.

[0062]

As described above, the first aspect of the present invention is as described above.
According to the dynamic press-fitting method and the vibration generating device used in the method described in any one of Items 9 to 9, a vibration generating device that is small and has good operability and workability, which can be actually applied to the dynamic press-fitting method, is provided at low cost. Therefore, the work of laying the small-diameter pipe can be easily and efficiently performed. or,
In the case of claim 4, since the vibration generating device can be used as a sub-propulsion mechanism of the main pushing device, it is easy to cope with the dynamic press-in method, and in the case of claim 5, the fluidity of the soil on the front surface of the tip head is improved. In this case, the press-fitting of the tip device can be performed more smoothly, and in the case of claim 6, the vibration state of the tip head can be detected easily and quickly, and in the case of claim 7, the vibration of the tip head can be detected. The state can be controlled easily and reliably. In the case of claim 8, the responsiveness of the hydraulic pressure is improved. In the case of claim 9, the piston does not rotate in the circumferential direction. Various excellent effects can be achieved, such as that the wires and pipes housed in the hollow portion are not twisted.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an example of an embodiment of a dynamic press-fitting method and a vibration generator used in the method.

FIG. 2 is a view taken in the direction of arrows II-II in FIG.

FIG. 3 is a view in the direction of arrows III-III in FIG. 1;

FIG. 4 is a hydraulic circuit diagram applied to a dynamic press-fitting method of the present invention and a vibration generator used in the method.

FIG. 5 is a control system diagram applied to a dynamic press-fitting method of the present invention and a vibration generator used in the method.

6 is a graph showing a change over time of a displacement amount of a tip head controlled by the control device shown in FIG. 5;

7 is a graph showing a temporal change in a thrust acting on a piston controlled by the control device shown in FIG. 5, that is, a load applied to a tip head.

FIG. 8 is a side view showing an outline of a pipe burying apparatus to which the vibration generator shown in FIGS. 1 and 2 is applied.

FIG. 9 is a side view showing an outline of a vibration generator used in a conventional press-fitting method.

10 is a side view showing an outline of a pipe burying device to which the vibration generator shown in FIG. 9 is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tip apparatus 4 Vibration generator 11 Tip outer cylinder 12 Tip inner cylinder 13 Piston 17 Tip head 18 Stroke detector 20 Lubricant supply nozzle (nozzle means) 22 Earth pressure detector 23 Acceleration detector 25 Rear cylinder 35 Detent Member 37 Hydraulic circuit 59 Pressure detector 60 Control device D1 Propulsion direction L Displacement amount P1 Earth pressure P2 Oil pressure (pressure) α Acceleration fo Vibration frequency Ca Displacement amplitude Wa Load amplitude

Continuation of the front page (72) Inventor Yuichi Miura 3-1-1-15 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries, Ltd. Tokyo Engineering Center (72) Inventor Minoru Tanaka 2-3-1 Otemachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Toshihiko Takanashi 2-3-1 Otemachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Hidenori Hino 2-3-3, Otemachi, Chiyoda-ku, Tokyo No. 1 Nippon Telegraph and Telephone Corporation F term (reference) 2D054 AC18 BA19 BA20 BB08 GA25 GA34 GA37 GA42 GA63 3H082 AA17 BB29 CC02 DD03 DD12 EE01

Claims (9)

[Claims] 1. A method in which a tip head attached to a tip of a piston in a propulsion direction is vibrated in a direction parallel to a propulsion direction in the ground to apply vibration to the ground and press the piston in a propulsion direction in the ground. A dynamic press-fitting method. 2. The dynamic press-fitting method according to claim 1, wherein the piston is vibrated in a direction parallel to the propulsion direction at a predetermined vibration frequency, displacement amplitude, or load amplitude. 3. A piston is fitted into a gap formed between the distal end outer cylinder and the distal end inner cylinder so as to be able to vibrate in a direction parallel to the propulsion direction. A vibration generating device having a tip head for giving vibration. 4. A stroke in a direction parallel to the propulsion direction of the piston is formed larger than the amplitude of the piston when vibrated, and the piston is moved larger than the amplitude when the piston is vibrated. The vibration generator according to claim 3, wherein the vibration generator is configured to be used as a propulsion mechanism. 5. The vibration generating device according to claim 3, further comprising nozzle means for supplying a lubricant along the front surface of the tip head on the front surface of the tip head. 6. A vibration detector for detecting a vibration state of a piston, a stroke detector for detecting a stroke of a piston, an acceleration detector for detecting acceleration of a tip head or a piston, and a piston in a propulsion direction. 6. A pressure detector for detecting a pressure of a fluid for operating the piston, and at least one of an earth pressure detector for detecting an earth pressure acting on a tip of the piston is provided. The vibration generator as described. 7. The vibration frequency, displacement amplitude, and load amplitude of the tip head based on at least one of the stroke of the piston, the acceleration of the tip head or the piston, the pressure of the fluid, and the earth pressure detected and fed back by each detector. 7. The vibration generator according to claim 3, further comprising a control device configured to control at least one of acceleration and acceleration. 8. A hydraulic circuit device for operating a piston and a control device, wherein at least the piston is provided in the hollow portion of the hollow rear cylinder connected to the distal end outer cylinder or the distal end inner cylinder. 8. The vibration generating apparatus according to claim 3, wherein a device for a hydraulic circuit for operating the device is housed. 9. A detent member for preventing the piston from rotating in the circumferential direction between the distal end inner cylinder and the piston or between the distal end outer cylinder and the piston. 9. The vibration generator according to 5, 6, 7, or 8.