JP2000145367A - Hydraulic feeder to hydraulic cylinder for compensation for buried-pipe jacking-direction compensator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make one hose serve the purpose of the two hoses of pressure-oil supply and pressure-oil return holes for supplying and discharging pressure oil to and from a hydraulic cylinder for compensating the jacking direction. SOLUTION: In the buried-pipe jacking-direction compensator, in which a cutting edge is connected in a freely oscillating manner by at least three compensation hydraulic cylinders, one pressure-oil supply-combining return hose 9 joined with a hydraulic-source unit comprising an oil tank 7, a hydraulic pump 8 or the like installed on the outside of a buried pipe is passed into the buried pipe and extended up to compensation hydraulic cylinders while the supply of pressure oil is conjoined with valves 15, 16 for changing over the expansion and contraction of each compensation hydraulic cylinder and each compensation hydraulic cylinder 22a-22b through valves for selecting driving, and an accumulator 30 receiving pressure oil pushed out from another section when pressure oil is fed is mounted while pressure oil accumulated in the accumulator 30 is returned to the oil tank 7 through the pressure-oil supply-combining return hose 9 when the expansion-contraction driving of each compensation hydraulic cylinder is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lateral excavation of a buried pipe such as a fume pipe, in which a cutting edge is connected to the tip of the buried pipe to be propelled by at least three hydraulic cylinders for correction. The present invention relates to a device for supplying hydraulic pressure to a hydraulic cylinder for correction in a buried pipe propulsion direction correcting device.

[0002]

2. Description of the Related Art Conventionally, as a hydraulic supply device of this type, a hydraulic oil supply unit such as an oil tank and a hydraulic pump is installed outside a buried pipe, and a hydraulic oil supply hose and a hydraulic oil return hose connected to the hydraulic power unit are provided. The two hoses are passed through the buried pipe and extended to the hydraulic cylinder for correction, where switching is performed for switching supply / discharge of pressurized oil to the head-side inner chamber and the rod-side inner chamber of each of the correcting hydraulic cylinders. Connected to the correction hydraulic cylinder via a solenoid valve for drive and a drive selection solenoid valve for supplying and discharging hydraulic oil only to the hydraulic cylinder necessary for correcting the propulsion direction among the correction hydraulic cylinders Are known.

However, in the above-mentioned conventional apparatus, two hoses, a pressure oil supply hose and a pressure oil return hose, must be provided in the buried pipe.
The work of adding two hoses becomes complicated, and a space for piping two hoses in a narrow buried pipe without any trouble must be secured.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to improve the conventional apparatus so that only two hoses, a pressurized oil supply hose and a pressurized oil return hose, are sufficient.

[0005]

As a means for achieving the above object, the present invention relates to a buried pipe having a cutting edge connected to the tip of a buried pipe to be propelled by at least three hydraulic hydraulic cylinders for correction. In the pipe propulsion direction correcting device, one pressure oil supply / return hose connected to a hydraulic source unit including an oil tank, a hydraulic pump, and the like installed outside the buried pipe is passed through the buried pipe, and the correction hydraulic pressure is passed. Extends to the cylinder and switches the supply of pressurized oil between the head-side inner chamber and the rod-side inner chamber of each of the correction hydraulic cylinders, and is necessary for correcting the propulsion direction of the correction hydraulic cylinders When the hydraulic oil is supplied to one of the head-side and rod-side inner chambers, it is connected to each correction hydraulic cylinder via a drive selection valve that selects the hydraulic oil supply to only the hydraulic cylinder. An accumulator is provided for receiving the pressurized oil extruded from one side, and the pressurized oil stored in the accumulator is returned to the oil tank through the pressurized oil supply / return hose when the expansion / contraction drive of each of the correcting hydraulic cylinders is stopped. The present invention proposes a hydraulic supply device for a hydraulic cylinder for correction of a buried pipe propulsion direction correcting device. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0006]

In FIG. 1, a short leading pipe (2) is detachably connected to the tip of a pipe (1) to be buried by side digging propulsion, and four pipes in this example are provided inside the leading pipe (2). The correction hydraulic cylinders (4a), (4b), (4c), and (4d) are separated from each other on an arc centered on the axis of the front pipe (2) at an interval of 90 degrees with respect to the axis. It is fixed in a parallel state, and a short cylindrical cutting edge (3) is connected to the front end of the front pipe (2) by the hydraulic cylinders for correction (4a) to (4d) so as to swing freely. (5) is a screw rod for discharging soil vertically rotatably passed through the pipe (1), and (6) is an excavating head connected to the tip of the screw rod (5).

The correcting hydraulic cylinders (4a) to (4)
The hydraulic supply to d) is as follows. Referring to FIG. 2, a hydraulic power source unit (A) mainly including an oil tank (7) and a hydraulic pump (8) is installed in a pit opened at the starting point of horizontal excavation propulsion. The hydraulic oil supply / return hose (9) connected to the pipe (1) extends through the pipe (1) to the front conduit (2), and the hydraulic pressure switching unit (B) disposed in the front conduit (2) ). In the hydraulic pressure source unit (A), a return oil passage (10) branched from the pressure oil supply / return hose (9) is connected to an oil tank (7) via a return switching solenoid valve (11). It is. The solenoid valve (11) is switchable between a return path and a closed path. (12) is a relief valve.

[0008] The structure of the hydraulic switching unit (B) is as follows. Referring to FIG. 2, the hose (9) is connected to the oil passage (1).
3) and (14), and both branch hoses (13) and (1)
4) Connect the expansion / contraction switching solenoid valves (15) and (16), which are switchable to a feed path, a return path and a closed path, respectively, and then a base oil path (17) drawn out of one of the solenoid valves (15). To oil passages (18), (19),
(20), branching into (21), each branch oil passage (18)-
(21) is a drive selection solenoid valve (22a), (22b), (22c), which can be switched between open and closed.
(22d) through the correction hydraulic cylinder (4a) to
An oil passage (2) connected to each head side inner chamber of (4d) and drawn out of the other solenoid valve (16).
3) is connected to the rod-side inner chamber of the correction hydraulic cylinder (4a), and the correction hydraulic cylinders (4a) and (4) are connected.
b), (4b) and (4c), and (4c) and (4d), the respective rod-side inner chambers are connected by oil passages (24), (25), and (26), respectively, and the expansion / contraction switching valve ( 1
5) and (16) are connected to the accumulator (30) via the base oil passage (29) via the oil passages (27) and (28) that are switchably connected to the return path and the closed path. Line (29) and the supply and return hose (9)
1), and the above-mentioned hose (9) is connected to the oil passage (31).
Check valve (3) for stopping the flow from the base oil passage (29)
2) is interposed.

The operation of the above-described hydraulic supply device will be described. Now, when the hydraulic cylinders for correction (4a) to (4d) are reduced and the blade (3) is in the normal posture as shown in FIG. 1, the hydraulic cylinders (4c) and (4c) are used for correcting the propulsion direction.
When only d) is to be driven to extend, as shown in FIG. 2, the operation of the selection solenoid valves (22c) and (22d) in the unit (B) causes the branch oil passages (20) and (21) to open in their open circuits. ) Are opened, and the branch oil passages (18) and (19) are closed by closing the solenoid valves (22a) and (22b) due to the non-operation of the solenoid valves (22a) and (22b). The oil passage (13) in the feed path due to non-operation,
(17) and the closed oil passage (1)
7) and (27) are shut off and the other solenoid valve (1
By the operation of 6), the oil passages (14) and (23) are shut off at the closed path, and the oil paths (23) and (28) are returned at the return path.
Communication.

In the unit (A), the return oil passage (10) is closed by the operation of the return switching solenoid valve (11).

If the valves are adjusted as described above, the pressure oil supplied from the hydraulic pump (8) is supplied to the supply / return hose (9), the branch oil passage (13), the switching solenoid valve (15), Base oil passage (17), branch oil passage (20), (2
1) and selection solenoid valves (22c), (22
d) is supplied to the head-side inner chambers of the correcting hydraulic cylinders (4c) and (4d).
c) and (4d) extend to incline the cutting edge (3) in a required direction, and correct the desired propulsion direction by the subsequent propulsion.

The correcting hydraulic cylinders (4c), (4
With the extension of d), the pressure oil in the rod-side inner chambers of the cylinders (4c) and (4d) becomes oil passages (26), (25),
(24), (23), solenoid valve for switching (1
6), is pumped into the accumulator (30) via the branch oil passage (28) and the base oil passage (29) and is accumulated.

Next, as shown in FIG. 3, the selection solenoid valves (22c) and (22d) are turned off, and the branch oil passages (20) and (21) are closed by their closed paths. The solenoid valve (16) is turned off to shut off the oil passages (23) and (28) when the solenoid valve is closed, and to communicate the oil passages (14) and (23) with the feed passage.
In the unit (A), the return switching solenoid valve (11) is turned off, and the return oil path (10) is opened in the return path.

If the valves are adjusted as described above, the high-pressure oil accumulated in the accumulator (30) is supplied to the base oil passage (29), the check valve (32), the supply / return hose (9),
The oil is returned to the oil tank (7) via the return oil passage (10) and the solenoid valve (11). At this time, the pressure oil sent from the hydraulic pump (8) is also returned to the oil tank (7) via the return oil passage (10).

To reduce the extended hydraulic cylinders (4c) and (4d) after the correction of the propulsion direction, see FIG.
As shown in the figure, the solenoid valves for selection (22c), (2
By the operation of 2d), the branch oil passages (20) at their open circuits,
(21) is opened and the switching solenoid valve (1
By the operation of 5), the oil passages (17) and (27) are provided on the return path.
And the oil passages (13), (1)
7) is shut off.

In the unit (A), the return oil passage (10) is closed by the operation of the return switching solenoid valve (11).

When the valves are adjusted as described above, the pressure oil supplied from the hydraulic pump (8) is supplied and returned by the supply / return hose (9), the branch oil passage (14), the switching solenoid valve (16) and the oil. Roads (23), (24), (25),
After (26), the hydraulic cylinder for correction (4c), (4d)
Of the cylinder (4).
c) and (4d) are reduced to return the inclined cut (3) to a normal posture.

As the hydraulic cylinders (4c) and (4d) are reduced in size, the pressure oil in the head-side inner chambers of the cylinders (4c) and (4d) is supplied to the oil passages (20) and (21) and the solenoid valve ( 22c), (22d), the base oil passage (17), the solenoid valve (15), the branch oil passage (27) and the base oil passage (29) to be pressure-fed to the accumulator (30) and accumulated.

Next, as shown in FIG. 5, the selection solenoid valves (22c) and (22d) are turned off, and the branch oil passages (20) and (21) are closed by closing these solenoid valves. The valve (15) is turned off, and the hoses (17) and (27) are shut off when the valve (15) is closed.
The feed path connects the oil paths (13) and (17), and in the unit (A), the return switching solenoid valve (11)
Is turned off, and the return oil passage (10) is opened at the opening.

With the above adjustment, the high-pressure oil accumulated in the accumulator (30) is returned to the oil tank (7) via the supply / return hose (9) as in FIG.

[0021]

According to the hydraulic pressure supply device for the correction hydraulic cylinder of the buried pipe propulsion direction correction device of the present invention, the pressure oil is supplied from the hydraulic power supply unit to the correction hydraulic cylinder by one pressure oil supply / return hose. It is possible to supply and discharge the hose, thereby simplifying the work of adding the hose accompanying the addition of the buried pipe, and also allowing the pipe to be easily piped into a narrow buried pipe.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a tip portion of a buried pipe in a horizontal digging type pipe burying apparatus.

FIG. 2 is a hydraulic circuit diagram in a state where two correction hydraulic cylinders are extended.

FIG. 3 is a drawing showing a state in which pressure oil of an accumulator is returned to an oil tank from the state of FIG. 2;

FIG. 4 is a drawing showing the same two hydraulic cylinders in a reduced state;

5 is a view showing the same state in which the pressure oil of the accumulator is returned to the oil tank from the state of FIG. 4;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Pipe to be embedded 3 Blade port 4a, 4b, 4c, 4d Hydraulic cylinder for correction 7 Oil tank 8 Hydraulic pump 9 Hydraulic oil supply and return hose A Hydraulic power source unit 15, 16 Solenoid valve for expansion / contraction switching) 22a, 22b, 22c , 22d Solenoid valve for drive selection 30 Accumulator B Hydraulic pressure switching unit

Claims (1)

[Claims] 1. A buried pipe propulsion direction correcting device having a cutting edge connected to a tip of a buried pipe to be propelled by at least three hydraulic cylinders for correction so as to swing freely. One pressure oil supply / return hose connected to a hydraulic source unit composed of an oil tank, a hydraulic pump, etc. is extended through the buried pipe to the correction hydraulic cylinder, and the supply of the pressure oil is adjusted to each of the corrections. Expansion / contraction switching valve for switching between the head-side inner chamber and the rod-side inner chamber of the hydraulic cylinder for driving, and a drive selection valve for selecting hydraulic oil supply only to the hydraulic cylinder required for correcting the propulsion direction among the correcting hydraulic cylinders An accumulator which is connected to each of the correction hydraulic cylinders via a, and which receives pressurized oil extruded from the other when the pressurized oil is supplied to one of the head-side and rod-side inner chambers And the hydraulic oil stored in the accumulator is returned to the oil tank through the hydraulic oil supply / return hose when the expansion / contraction drive of each of the hydraulic cylinders for correction is stopped. A device for supplying hydraulic pressure to the cylinder.