JPH0527598Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hydraulic circuit for an erector device for a shield excavator that excavates a tunnel or the like.

[Conventional technology]

Conventionally, as a hydraulic circuit for an erector device for constructing segments, a configuration shown in FIG. 2 is known.

In the figure, A indicates the trolley side, and B indicates the shield tunneling machine main body side (hereinafter referred to as "main body side B"). They are 100m apart. Between the truck side A and the main body side B are a pump line 1 that supplies high-pressure hydraulic oil, a tank line 2 that returns hydraulic oil to a hydraulic oil tank 4 (described later), and a hydraulic oil that leaks from an erector motor 9 (described later). It is connected by a drain line 3 etc. that returns to the hydraulic oil tank 4.

Here, a hydraulic oil tank 4 for storing hydraulic oil is provided on the truck side A, and a power unit 6 consisting of a suction filter 5, an electric motor 6A, and a hydraulic pump 6B is provided on the pump line 1 side, and a power unit 6 is provided on the tank line 2 side. A return filter 7 is provided, and a pressure setting circuit 8 is provided between the pump line 1 and the tank line 2.

The pressure setting circuit 8 includes a check valve 8A provided in the pump line 1, a variable set pressure relief valve 8B provided between the pump line 1 and the tank line 2, and a neutral valve with one port blocked. Position 4 consists of position A, left and right switching positions B and C, and controls the relief setting pressure of relief valve 8B.
If the port solenoid valve 8C and the relief pressure are, for example, 140
Kgf/cm ² and another relief valve 8D, the solenoid valve 8C is in the left switching position B when operating the erector motor 9, which will be described later, and is in the right switching position when operating the erector jack 10. When both the erector motor 9 and the erector jack 10 are in a non-operating state, the switching operation is performed so that the erector motor 9 and erector jack 10 are in the neutral position A. Now, when the solenoid valve 8C is in the neutral position A, the vent port of the relief valve 8B is connected to the tank line 2 side, the relief setting pressure is set to substantially 0 kgf/cm ² , and the pressure in the pump line 1 is Oil is relieved into the tank line 2 via the check valve 8A and the relief valve 8B, and the pump line 1 is in an unloaded state. On the other hand, when the solenoid valve 8C is switched to the switching position B, the vent port of the relief valve 8B is substantially closed.
The pump line 1 is set to the maximum setting pressure of the relief valve 8B, for example, 210 Kgf/cm ² . moreover,
When the solenoid valve 8C is switched to the switching position C, the vent port of the relief valve 8B is connected to the tank line 2 via the relief valve 8D, the relief set pressure is set to, for example, 140 Kgf/cm ² and the pump line 1 The pressure oil inside is supplied at this pressure.

Further, on the main body B side, there is an erector motor 9 for rotating the erector, and an erector sliding jack 10.
A and erector pressing jacks 10B ₁ , 10B ₂
It consists of an electric jack 10 and a control circuit unit 11. The control circuit unit 11 is a 3-position, 4-port electromagnetic circuit for operating an erector provided between the pump line 1, the tank line ₂ , the erector motor 9, the sliding jack 10A, and the pressing jacks 10B1, _10B2, respectively. Valve 1
1A, 11B, and 11C, and between the solenoid valve 11A and the erector motor 9 there is a brake valve 11D for preventing runaway, and an overload relief valve 1 for preventing overload.
1E is provided, and a solenoid valve 11B and a sliding jack 1 are provided.
A speed regulating valve 11F is provided between the solenoid valve 11C and the pressing jacks 11B ₁ , 11
A pilot check valve 11G and a speed adjustment valve 11H are provided between the engine and the engine _B2 .

In the hydraulic circuit configured as described above, when each of the solenoid valves 11A to 11C of the control circuit unit 11 is in the neutral position and both the erector motor 9 and the erector jack 10 are in a non-operating state, the pressure setting circuit 8 is set. Variable pressure relief valve 8
The relief setting pressure of B is substantially 0 kgf/ ^cm2 , and the pressure oil from pump line 1 is transferred to hydraulic oil tank 4.
The load on the electric motor 6A of the power unit 6 is reduced to the minimum in an unloaded state, thereby saving energy.

Further, in order to rotate the erector motor 9, the erector operating solenoid valve 11A is switched to a desired switching position, and the solenoid valve 8C of the pressure setting circuit 8 is switched to the switching position B. As a result, the pressure in the pump line 1 meets the specifications of the erector motor 9.
The rated pressure is set at 210Kgf/cm ² .

Furthermore, in order to operate the erector jack 10, either one of the erector operating solenoid valves 11B and 11C,
Alternatively, both are selected and the solenoid valve 8C is switched to the switching position C. As a result, the pressure in the pump line 1 met the specifications of the erector jack 10.
The rated pressure is set at 140Kgf/cm ² .

[Problem that the invention attempts to solve]

However, in order to increase the operating pressure in the pump line 1 from the unloaded state to the point where the erector motor 9 and erector jack 10 operate using the pressure setting circuit 8, the relief valves 8B and 8D and the solenoid valve 8C are required.
There is a problem that it takes about 0.5 to 2.0 seconds due to the switching time, the time to expand the inside of the hose constituting the pump line 1, the length of the hose of the pump line 1, etc. For this reason, the inching operation cannot be performed instantaneously, and it takes a lot of time to perform alignment to grasp the segments, maintain the roundness of the segments, and align the holes for fastening bolts. was.

On the other hand, during temporary excavation at the beginning of excavation, the main body of the shield excavator and the trolley are placed far apart until there is space to place the trolley, so the hose length of the pump line 1 becomes extremely long, and the length of the hose for the pump line 1 becomes extremely long, and There is a problem in that it takes nearly 4 seconds for the inching to operate, making it impossible to perform an inching operation when constructing segments.

The present invention was developed in view of the problems of the conventional technology, and it reduces the time required to raise the rated pressure of the erector motor and erector jack of the erector device to the rated pressure that meets the specifications, thereby reducing the inching operation during segment construction. It is an object of the present invention to provide a hydraulic circuit for an erector device for a shield excavator that can perform reliably.

[Means for solving problems]

In order to solve the above problems, the present invention provides a hydraulic pump and a tank provided on the truck side, an erector motor and an erector jack provided on the excavator main body side, and a combination of the hydraulic pump, tank, erector motor, and erector jack. A pump line and a tank line are respectively connected between the pump line and the tank line, which are provided on the truck side, and when the erector motor and erector jack are in an inactive state, the pressure of the pump line is unloaded, and the erector motor and erector jack are in an operating state. In the hydraulic circuit of the erector device for a shield excavator, the pressure setting circuit includes a pressure setting circuit that generates a predetermined pressure in the pump line when the erector motor and the erector jack are in the non-operating state. It is characterized by the provision of a relief valve that constantly generates a small pressure in the pump line.

[Effect]

Even in the unloaded state, a small pressure is always maintained in the pump line to operate the erector motor and erector jack.
Since the pressure is increased to the rated pressure, the time can be significantly shortened, and inching operations during segment assembly can be performed reliably.

〔Example〕

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. Note that the same components as those in the prior art shown in FIG. 2 are given the same reference numerals, and their explanations will be omitted.

However, 21 is a pressure setting circuit according to the present embodiment, and the pressure setting circuit 21 is provided with a check valve 8A, a variable set pressure type relief valve 8B, a solenoid valve 8C, and a relief valve 8D as in the prior art. Although a solenoid valve 8C and a relief valve 8D are provided,
This embodiment differs in that a third relief valve 22 is provided between the electromagnetic valve 8C and the tank line 2.

Here, the relief setting pressure of the third relief valve 22 is set to a small pressure in the range of 10 to 40 kgf/cm ² , and when the solenoid valve 8C is in the neutral position A, the relief setting of the variable set pressure relief valve 8B is set. pressure 10
~40 Kgf/cm ² , and is configured to maintain a small pressure in the pump line 1 even when the erector motor 9 and erector jack 10 are inactive. Note that the relief valve 22
For example, a variable set pressure relief valve is used that can arbitrarily adjust the relief set pressure in the range of 0 to 50 kgf/cm ² .

Although the present embodiment is constructed as described above, the basic operation of the hydraulic circuit as a whole is not particularly different from that of the prior art.

Therefore, in this embodiment, by providing the third relief valve 22, even when the erector devices such as the erector motor 9 and the erector jack 10 are in a non-operating state, that is, even when the solenoid valve 8C is in the neutral position A. The relief setting pressure of the variable setting pressure type relief valve 8B can be arbitrarily set in the range of 10 to 40 kgf/cm ² . Therefore, a small pressure of 10 to 40 Kgf/cm ² can always be generated in the pump line 1. As a result, in order to operate the erector motor 9 and erector jack 10, the solenoid valve 11A
~11C is selected and switched, and at the same time, the solenoid valve 8C is switched from neutral position A to switching position B or C, 10 to 40 kg generated in pump line 1.
The pressure will be increased from f/cm ² to the rated pressure.

Thus, even taking into account the switching time of the solenoid valve 8C and the relief valve 8B, the expansion time of the hoses forming the pump line 1, the hose length of the pump line 1, etc., the time required to increase the pressure to a predetermined rated pressure is: It can be shortened to less than 0.1 seconds.

By the way, in the case of the erector device, the inching operation is necessary for positioning to grasp the segments, to maintain the roundness of the segments, and to align the tightening bolt holes. This is a necessary operation, but in this embodiment, the pressure in the pump line 1 can be increased to the rated pressure within 0.1 seconds, so the inching operation can be performed instantly and the segment assembly time can be shortened. I can do it.

[Effect of idea]

The hydraulic circuit of the erector device for a shield tunneling machine according to the present invention is as described above in detail, and the pressure setting circuit includes a relief valve that constantly generates a small pressure in the pump line even when the erector motor and erector jack are inactive. Because of this configuration, the time it takes to raise the pump line to the predetermined rated pressure during operation can be significantly shortened, and the inching operation required for the erector device can be performed instantly and reliably, and moreover, fine inching can be performed. Since it is easy to operate, the segment construction time can be kept short, and the construction period for one construction section can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a hydraulic circuit according to this embodiment, and FIG. 2 is a block diagram of a hydraulic circuit according to a conventional technique. 1...Pump line, 2...Tank line, 4
...Hydraulic oil tank, 6...Power unit, 6A
...Electric motor, 6B...Hydraulic pump, 8,21...
Pressure setting circuit, 8A...Check valve, 8B...Variable set pressure relief valve, 8C, 11A, 11B,
11C... Solenoid valve, 8D, 22... Relief valve,
9...Erector motor, 10...Erector jack, A...Dolly side, B...Main body side.

Claims (1)

[Scope of utility model registration request] A hydraulic pump and tank provided on the trolley side,
An erector motor and an erector jack provided on the excavator main body side, a pump line and a tank line that respectively connect the hydraulic pump and tank to the erector motor and erecta jack, and a pump line and a tank line provided on the truck side and connected to the erector motor and erecta jack. Hydraulic pressure of an erector device for a shield excavator, comprising a pressure setting circuit that unloads the pressure in the pump line when the erector motor and erector jack are in an operating state, and generates a predetermined pressure in the pump line when the erector motor and erector jack are in an operating state. In the circuit, the pressure setting circuit includes:
A hydraulic circuit for an erector device for a shield excavator, characterized in that a relief valve is provided to constantly generate a small pressure in the pump line even when the erector motor and the erector jack are in a non-operating state.