JPH0942201A - Leakage oil discharge device for hydraulic equipment installed in the front conduit - Google Patents

Abstract

(57) [Abstract] [Purpose] To prevent the rise of back pressure of leaking oil generated from the hydraulic devices 9, 19 and 20 in the front conduit 8 of the small diameter buried pipe propulsion device, to prevent the hydraulic devices 9, 19 and 20 from being increased. (EN) Provided is a leakage oil discharge device for a hydraulic device installed in a leading conduit for protection. In a leak oil discharge device for hydraulic devices 9, 19, 20 installed in a front conduit 8 of a small-diameter pipe burying device, a leak oil for temporarily storing leak oil generated from the hydraulic devices 9, 19, 20. The leak oil tank 17 comprises a tank 17, a leak oil pump 20 for discharging the leak oil of the leak oil tank 17 to the outside of the leading conduit 8 and the buried pipe 5, and a leak oil pump drive means 19. An oil pump 20 and a leak oil pump drive means 19 are installed in the front conduit 8. A leak oil discharge device for hydraulic equipment installed in the front conduit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leak oil discharge device for hydraulic equipment installed in a front conduit of a small-diameter buried pipe propulsion device, and in particular, the distance between vertical shafts is increased to improve the efficiency of propulsion construction of the buried pipe. In this case, the present invention relates to a leakage oil discharge device for hydraulic equipment installed in the front conduit for protecting the hydraulic equipment by preventing an increase in leak oil back pressure generated from the hydraulic equipment in the front conduit.

[0002]

2. Description of the Related Art A small-diameter buried pipe propulsion device is a method for rotatably driving a cutter head rotatably mounted at the front end of a leading conduit to propel a small-diameter buried pipe behind the leading conduit while excavating the ground. There is. In this small-diameter buried pipe propulsion method, the cutter head is normally driven to rotate by the cutter drive motor installed in the leading conduit, and the hydraulic circuit thereof is shown in FIG. A cutter operating valve 51 for switching the pressure oil pipe P and the return pipe T connected to a hydraulic unit installed in a shaft (not shown) in FIG. 4 is operated by a solenoid 51a operated by a signal from a ground control device (not shown). 4 cutter drive motors 5
It is operated so that the rotation direction of 2 can be switched. In addition,
From the pressure oil conduit P and the return conduit T, similarly to the cutter driving motor 52, a swinging jack for articulating the leading conduit is driven and operated.
Leakage oil generated from the four cutter drive motors 52 is piped so as to be discharged to the return pipe lines T connected to the hydraulic unit via the leak oil pipe lines 53, respectively. It is laid so that it can be returned independently to the tank in the hydraulic unit. Alternatively, as shown in FIG. 5, the leak oil pipeline 53 is directly discharged to the rear of the buried pipe.

[0003]

However, recently, in order to improve the efficiency of propulsion and construction of a buried pipe, the distance between vertical shafts is increased, and in order to facilitate the movement of the hydraulic unit, the hydraulic unit is not placed in the vertical shaft. , It tends to be installed on the ground. In such a case, according to the above-mentioned conventional technique, the leak oil conduit 53 and the return conduit T become long, so that not only the back pressure of the leak oil generated from the cutter drive motor 52 increases but also the hydraulic unit. The back pressure of the leaked oil is further increased by the amount of the head due to the difference in height between the vertical shaft where the is installed and the ground.

To explain the above theoretically, the pressure loss Δp in the laminar flow in a circular pipe is Δp according to Hagen-Poiseuille's law, where μ: viscosity coefficient, l: pipe length, w: average flow velocity, d: pipe diameter. = 8 μl w / d ² . In this equation, the viscosity coefficient μ changes exponentially with temperature, so the back pressure of the leaked oil rises especially at low temperatures. Therefore, the back pressure of the leaked oil causes a problem of breaking the case and the seal of the cutter driving motor 52, and therefore the propelling distance between the vertical shafts must be 70 m or less at most. There is also a method of increasing the pipe diameter d to reduce the pressure loss Δp in order to increase the distance between the vertical shafts, but there is a problem in space in the leading pipe of the small-diameter buried pipe. The present invention has been made in order to solve the problems in the above-mentioned conventional technology, and forcibly discharges the leakage oil of the hydraulic equipment installed in the front conduit with a leakage oil pump, so that the oil pressure installed in the front conduit is reduced. An object of the present invention is to provide a leakage oil discharge device for hydraulic equipment installed in a leading conduit, which is designed to protect the equipment.

[0005]

In order to achieve the above object, a leakage oil discharge device for hydraulic equipment installed in a leading conduit according to the present invention is a hydraulic equipment installed in the leading conduit of a small diameter pipe burying device. In the leak oil discharge device, a leak oil tank for temporarily storing leak oil generated from the hydraulic equipment, a leak oil pump for discharging the leak oil of the leak oil tank to the outside of the leading conduit and the buried pipe, and the leak oil It comprises pump drive means, and these leak oil tank, leak oil pump and leak oil pump drive means are installed in the leading conduit.

The leak oil pump drive means may be a hydraulic motor, and the hydraulic equipment for temporarily generating the leak oil stored in the leak oil tank includes a cutter drive motor, a leak oil pump and a leak oil pump drive motor in the leading conduit. The leak oil tank may be at least one, and the leak oil tank may be a closed tank. A level sensor that detects the amount of oil in the leak oil tank and a leak oil pump drive motor are rotated by the detection signal of the level sensor. And a control valve that controls the rotation of the leak oil pump drive motor to be stopped by the non-detection signal of the level sensor.

[0007]

The leak oil discharge device for hydraulic equipment installed in the leading conduit having the above-described structure operates as follows. Leakage oil generated from hydraulic equipment installed in the front pipe of the small diameter pipe burying device is temporarily stored in the leak oil tank installed in the front pipe, and the leak oil in this leak oil tank is leaked in the front pipe. A leaking oil pump driven by an oil pump driving means forcibly discharges the oil to the outside of the lead pipe and the buried pipe.

If a hydraulic motor is used as the leak oil pump drive means, an insulating means such as an electric motor is not required, and a leak generated from at least one hydraulic device of the cutter drive motor, the leak oil pump and the leak oil pump drive motor is eliminated. The oil is temporarily stored in the leaking oil tank, but since this tank is a closed tank, it will not mix with the drain oil even if groundwater enters the leading conduit. When the level sensor detects that the oil amount in the leaking oil tank has reached a predetermined level, the leaking oil pump drive motor is rotated, and if the level sensor does not reach the predetermined level, the leaking oil tank leaks. The operation valve is controlled so as to stop the rotation of the oil pump drive motor, and the leak oil pump is driven only when necessary.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION One embodiment of a leak oil discharge device for hydraulic equipment installed in a leading conduit according to the present invention will be described in detail below with reference to FIGS. FIG. 1 is a schematic view showing the whole of a small diameter buried pipe propulsion device, FIG. 2 is a view showing details in a leading conduit of a leak oil discharge device according to the present invention, and FIG. 3 is a hydraulic circuit of the leak oil discharge device according to the present invention. FIG.

As shown in FIGS. 1 and 2, the control device and the hydraulic unit 2 installed on the ground on the side of the starting shaft 1 are the propulsion device installed in the starting shaft 1 via the first hydraulic pipe 3. 11 is connected to a propulsion jack 12 and a screw conveyor drive 13. The hydraulic unit 2
Is connected to a cutter drive motor 9 installed in the front conduit 8 via a second hydraulic pipe 7 installed along the outer diameter portion of the casing 6 in the first hydraulic pipe 3 and the buried pipe 5. . The cutter head 10 is rotatably mounted on the front conduit body 8a of the front conduit 8 via a bearing 16, and the propulsion jack 12 is installed on the propulsion device 11 in the starting shaft 1.
Thus, a propulsive force acts on the cutter head 10 via the embedded pipe 5 and the leading conduit 8. A chamber 15 is formed in the front conduit 8 at the rear of the cutter head 10, and a screw shaft 14a that is driven to rotate by a screw conveyor drive device 13 over the starting shaft 1 and a screw conveyor 14 including a casing 6 are installed behind the chamber 15. Has been done.

A cutter drive motor 9 is provided in the leading conduit 8.
A leak oil tank 17 for discharging leak oil generated from the tank is installed. The leak oil tank 17 has a sealed tank structure in consideration of submersion in water. When the leaked oil in the leaked oil tank 17 reaches a certain amount, the leaked oil pump 20 driven by the leaked oil pump drive motor 19 causes the leaked oil tank 1 to leak.
The leak oil in 7 is forcibly discharged to the outside of the leading conduit 8 and the buried pipe 5. Further, the hydraulic unit 2 and the rocking jack 21 are connected via the second hydraulic pipe 7 in order to control the propulsion direction by articulating the leading conduit 8.

The operation of FIGS. 1 and 2 will be described.
The hydraulic oil supplied from the control device and the hydraulic unit 2 installed on the ground on the side of the starting shaft 1 through the first hydraulic pipe 3 was installed along the outer diameter portion of the casing 6 in the buried pipe 5. The cutter drive motor 9 installed in the front conduit 8 is operated via the second hydraulic pipe 7. As a result, the cutter head 10, which is rotatably attached to the main body 8a of the front conduit 8 via the bearing 16, is rotationally driven, and at the same time, the propulsion jack 12 installed on the propulsion device 11 in the starting shaft 1 is driven. As a result, a propulsive force acts on the cutter head 10 via the buried pipe 5 and the front conduit 8, so that the cutter head 10 excavates the natural ground. The earth and sand excavated from the ground is taken into the chamber 15, and then the starting shaft 1 is driven by the screw conveyor 14 including the screw shaft 14a and the casing 6 which are rotationally driven by the screw conveyor driving device 13.
Discharged to the side.

The leak oil generated from the cutter drive motor 9 is discharged to the leak oil tank 17, and the leak oil tank 1
Since 7 has a sealed tank structure, even if it is submerged in water, the leaked oil will not be mixed with water. When a certain amount of leaked oil is accumulated in the leaked oil tank 17, the leaked oil pump drive motor 19 drives the leaked oil pump 20, so that the leaked oil in the leaked oil tank 17 is forced out of the front conduit 8 and the buried pipe 5. Will be discharged. In addition, the second hydraulic pipe 7
Rocking jack 21 connected to the hydraulic unit 2 via
Thus, the leading conduit 8 can be articulated to control the propulsion direction of the buried pipe.

As shown in FIG. 3, the cutter driving motor 9 and the control unit / hydraulic unit 2 installed on the ground are connected via a cutter operating valve 4 by a pressure oil conduit P and a return conduit T. It Solenoid 4a of this cutter operation valve 4
Is connected to the control unit / hydraulic unit 2 installed on the ground by electric wiring. The case of the cutter drive motor 9 is provided with a leak oil pipe 22a, and a closed leak oil tank 1 is provided.
7 is connected. The leak oil tank 17 has a level sensor 2
3 is installed, and when the leaked oil level reaches a predetermined height,
The solenoid 25a of the leak oil pump operating valve 25 is energized from the power source 24 via the level sensor 23. The leak oil pump operating valve 25 energized by the solenoid 25a is switched to the b position, the hydraulic oil is sent from the hydraulic unit 2 to the leak oil pump drive motor 19 via the pressure oil pipe P, and the leak oil tank 17 inside When the leaked oil is below a predetermined height, the power supply 24 cuts off the power supply to the solenoid 25a, the leaked oil pump operation valve 25 switches to the a position, and the hydraulic unit 2
The oil supply to the leak oil pump drive motor 19 is cut off.

The leak oil forcibly discharged from the leak oil pump 20 is sent to the return pipe T of the cutter drive motor 9 together with the return oil of the leak oil pump drive motor 19 and returned to the ground hydraulic unit 2. Further, both the case of the leak oil pump 20 and the case of the leak oil pump drive motor 19 are connected to the leak oil tank 17 through a leak oil pipe 22b.

The operation of FIG. 3 will be described. The leak oil generated from the drive motor 9 is discharged to the leak oil tank 17 via the leak oil pipe 22a. A level sensor 23 is installed in the leak oil tank 17, and when the leak oil surface reaches a predetermined height, the solenoid 25a of the leak oil pump operation valve 25 is energized from the power source 24 via the level sensor 23. The leak oil pump operation valve 25 is switched to the b position.
Therefore, when the hydraulic oil is sent from the hydraulic unit 2 to the leak oil pump drive motor 19 via the pressure oil pipe P, the leak oil pump 20 rotates, and the leak oil in the leak oil tank 17 falls below a certain level, The solenoid 25a is de-energized and the leak oil pump operating valve 25 is switched to the a position. Therefore, the hydraulic oil to the leak oil pump drive motor 19 is stopped, so that the leak oil pump 20 is stopped.

The leak oil forcibly discharged from the leak oil pump 20 is sent to the return circuit T of the cutter drive motor 9 together with the return oil of the leak oil pump drive motor 19. As described above, the leak oil pump 20 is rotationally driven only when the leak oil surface of the leak oil tank 17 detected by the level sensor 23 reaches a predetermined height, and otherwise the leak oil pump 20 is stopped. To prevent unnecessary rotation. Further, all the leak oil of the cutter drive motor 9, the leak oil pump 20, and the leak oil pump drive motor 19 is leak oil pipe 22.
It is discharged to the leak oil tank 17 via a and 22b.

[0018]

As described above, the following effects can be obtained by the leakage oil discharge device for hydraulic equipment installed in the leading conduit according to the present invention. (1) Since the leak oil of the hydraulic equipment installed in the leading conduit is forcibly discharged by the leak oil pump, the back pressure acting on the hydraulic equipment is reduced, so that the following effects are obtained. Conventionally, the distance between vertical shafts, which was limited to about 70 m, is about 20.
Since it can be extended to 0 m, it is possible to significantly reduce the construction period and the construction cost. Even if the hydraulic unit is installed from the vertical shaft to the ground in order to reduce the man-hours required for transportation and transportation, the back pressure of the leaked oil will not increase by the amount of the head due to the difference in height, which is also significant from this aspect. It is possible to reduce the construction period and the construction cost. (2) If the hydraulic oil pump driving means is replaced by a hydraulic motor, an insulating means such as an electric motor is not required and the safety against electric shock accident is improved. (3) Since the leaked oil from the hydraulic equipment installed in the front conduit is forcibly discharged, not only the distance between the vertical shafts becomes longer, but also the hydraulic equipment is installed on the ground from the vertical shaft. Since the leakage hydraulic pressure of No rises abnormally, it is possible to reliably protect the hydraulic equipment installed in the leading conduit. (4) Since the leak oil tank that temporarily stores the leak oil generated from the hydraulic equipment has a closed tank structure, even if groundwater enters the leading conduit, it does not mix with the leak oil. (5) Since the leak oil pump is driven only when the amount of oil in the leak oil tank reaches a predetermined level, it is not necessary to constantly operate the leak oil pump, and the power required for the operation can be saved.

[Brief description of drawings]

FIG. 1 is a schematic view showing an entire small-diameter buried pipe propulsion device.

FIG. 2 is a diagram showing details of the inside of the leading conduit of the leakage oil discharge device according to the present invention.

FIG. 3 is a diagram showing a hydraulic circuit of a leakage oil discharge device according to the present invention.

FIG. 4 is a diagram showing a conventional technique.

FIG. 5 is a diagram showing a conventional technique.

[Explanation of symbols]

1 ... Starting shaft, 2 ... Control device and hydraulic unit, 3 ... First
Hydraulic pipe, 4 ... Cutter operating valve, 5 ... Buried pipe, 6 ... Casing, 7 ... Second hydraulic pipe, 8 ... Lead conduit, 8a ... Lead conduit body, 9 ... Cutter drive motor, 10 ... Cutter head, 11
... Propulsion device, 12 ... Propulsion jack, 13 ... Screw conveyor drive device, 14 ... Screw conveyor, 14a ... Screw shaft, 15 ... Chamber, 16 ... Bearing, 17 ... Leak oil tank, 19 ... Leak oil pump drive motor (leak oil) Pump driving means), 20 ... leaking oil pump, 21 ... rocking jack,
22a, 22b ... Piping, 23 ... Level sensor, 24 ... Power supply, 25 ... Leakage oil pump operating valve, 25a ... Solenoid.

Claims (5)

[Claims] 1. A leak oil discharge device for a hydraulic device installed in a tip conduit of a small-diameter pipe burying device, and a leak oil tank for temporarily storing leak oil generated from the hydraulic device, and a leak oil for this leak oil tank. And a leak oil pump for discharging the oil to the outside of the lead pipe and the buried pipe, and the leak oil pump drive means. The leak oil tank, the leak oil pump, and the leak oil pump drive means are installed in the lead pipe. A leaking oil discharge device for hydraulic equipment installed in the destination conduit. 2. The leakage oil discharge device for hydraulic equipment installed in the front conduit according to claim 1, wherein the leakage oil pump drive means is a hydraulic motor. Leakage oil discharge device. 3. The leak oil discharge device for hydraulic equipment installed in the lead conduit according to claim 2, wherein the hydraulic equipment for generating leak oil temporarily stored in the leak oil tank includes a cutter drive motor in the lead conduit, and a leak. At least one of an oil pump and a leak oil pump drive motor, and a leak oil discharge device for hydraulic equipment installed in a leading conduit. 4. The leaked oil discharge device for hydraulic equipment installed in the lead conduit according to claim 1, wherein the leaked oil tank is a closed tank. 5. A leak oil discharge device for hydraulic equipment installed in the lead pipe according to claim 1, wherein a level sensor for detecting the amount of oil in the leak oil tank, and a leak oil pump drive by a detection signal of the level sensor. A leak oil discharge device for hydraulic equipment, comprising: an operation valve that controls a motor to rotate and stop the rotation of a leak oil pump drive motor according to a non-detection signal of a level sensor.