JP2001074004A - Control method of and control circuit of driving jack, and cutter driving method of and cutter driving device for underground excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently obtain cutter torque by controlling pressure of a hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in a cylinder so that pushing-out force and pulling-in force of a piston rod become almost the same. SOLUTION: A directional control valve 18 is switched to an upside-down Y-shape position (a letter corresponding to the first square form of the Japanese alphabet) to be controlled under pressure P2 and a flow rate Q1, a piston 3 is pushed by a hydraulic fluid supplied to the piston head chamber side in a cylinder 2, and a piston rod 4 is pushed out by pushing-out force F and a pushing-out speed V according to this. Next, the directional control valve 18 is switched to a square-shape position (a letter corresponding to the second square form of the Japanese alphabet) to be controlled under pressure P1 and a flow rate Q2, the piston 3 is pushed by a hydraulic fluid supplied to the piston rod chamber side in the cylinder 2, and the piston rod 4 is pulled in by pulling-in force F' and a pulling-in speed V' to thereby reduce a fluctuation in torque generated by a driving jack 1 as well as to efficiently obtain cutter torque.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control method and a control circuit for a hydraulically operated drive jack having a cylinder, a piston and a piston rod, and a ground incorporating the control method and control circuit for the drive jack. The present invention relates to a cutter driving method and a cutter driving device for a middle excavator.

[0002]

2. Description of the Related Art FIG. 8 is a schematic view of a driving jack according to the present invention.

The drive jack 1 shown in FIG. 8 has a cylinder 2, a piston 3, and a piston rod 4. The approach passage 5 is connected to the piston head chamber side of the cylinder 2, and the return passage 6 is connected to the piston rod chamber side.

When the piston rod 4 is pushed out, the working fluid is supplied to the piston head chamber side of the cylinder 2 through the approach passage 5, and when the piston rod 4 is retracted, the working fluid is operated toward the piston rod chamber side of the cylinder 2 through the return passage 6. Supply liquid.

Meanwhile, the pressure receiving area receiving the hydraulic pressure in the pressure receiving area A ₁ of the piston, which reduce the cross sectional area a of the piston rod 4 from the pressure receiving area A ₁ of the piston when the retract piston rod 4 when pushing the piston rod 4 receive the hydraulic pressure in the a _2. Therefore, the retraction force of the piston rod 4 is smaller than the pushing force of the piston rod 4 by an amount corresponding to the cross-sectional area a of the piston rod 4.

Next, FIG. 9 is an explanatory view of a crank mechanism for converting a linear reciprocating motion of a piston rod of a driving jack into a rotary motion.

In the crank mechanism shown in FIG. 9, the end of the driving jack 1 on the cylinder side is pivotally supported via a mounting pin 18 on a bracket 7 fixed to a fixing member. It is attached so that it can swing around the center. On the other hand, the crank 9 includes a crank arm 10, a crank shaft 11, and a crank pin 12.
And is configured. And the crank arm 1
The end of the piston rod 4 of the drive jack 1 is connected to the 0 crank pin 12.

In this crank mechanism, in FIG. 9, when the crank 9 rotates clockwise, a straight line connecting the rotation center O of the crank 9 and the mounting pin 8 of the driving jack 1 is set as a reference (0 °). The angle formed between the straight line connecting the rotation center O of the crank 9 and the mounting pin 8 of the driving jack 1 and the straight line connecting the mounting pin 8 of the driving jack 1 and the crank pin 12 is θ _1.
, That is, when the angle between the drive jack 1 and the crank arm 10 becomes a right angle, the torque generated by the drive jack 1 is the largest.

When the control circuit of the drive jack 1 switches from pushing to pulling of the piston rod 4 in the vicinity of the rotation of the crank 9 by 180 ° around the rotation center O, as described above, the piston rod 4 Since the retraction force of the piston rod 4 is smaller than the pushing force by an amount corresponding to the cross-sectional area a of the piston rod 4, the torque generated by the drive jack 1 is reduced.

FIG. 11 shows a change in torque generated by the driving jack when the piston rod of the driving jack makes one reciprocation, that is, when the crank makes one rotation in the crank mechanism shown in FIG.

From FIG. 11, the maximum torque T 'when operating the piston rod 4 toward the retracted side is smaller than the maximum torque T when the driving jack 1 operates the piston rod 4 toward the pushing side. You can see that.

FIG. 13 is a torque diagram generated by the four driving jacks as described above.
The lower part of FIG. 3 shows the fluctuation of the torque generated by each of the four driving jacks in one cycle, and the upper part shows the fluctuation of the combined torque of the four driving jacks.

FIG. 13 shows that the difference between the peaks and valleys in the combined torque of the four drive jacks is large, and the variation in the combined torque is large.

[0014]

[SUMMARY OF THE INVENTION However, with respect to the pressure receiving area A ₁ of the piston head chamber side of the piston of the power jack in the prior art, the cross-sectional area a substantial pressure receiving area A ₂ is the piston rod 4 of the piston rod chamber side No special measures have been taken to reduce the retracting force with respect to the pushing force of the piston rod 4 by a small amount.

As a result, for example, a conventional technique is directly employed in a cutter driving method or a cutter driving apparatus for generating a torque by a plurality of drive jacks, transmitting the torque to the cutter through a crank and a cutter rotating shaft, and rotating the cutter. In such a case, as shown in FIG. 13, there is a problem that the fluctuation of the combined torque is large and a smooth and efficient cutter torque cannot be obtained.

Further, in the prior art with respect to the extrusion speed of the piston rod 4 since the pressure receiving area A ₂ of the pressure receiving area of the piston head side A ₁ and the piston rod side of the piston 3 is in the relation of A _1> A ₂ No special countermeasures have been taken for slowing down.

Therefore, when the conventional technique is directly incorporated into a cutter driving method or a cutter driving device for rotating a cutter by using a plurality of driving jacks 1, the driving jack in the retracted state of the piston rod 4 becomes the piston rod 4. May act as a brake for the drive jack in the pushed-out state, and as a result, there is a problem that a smooth and efficient cutter torque cannot be obtained.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a drive jack capable of making the pushing force and retraction force of a piston rod in a driving jack, or the pushing and retraction speeds substantially the same. To provide a control method and a control circuit.

Another object of the present invention is to provide a cutter driving method and a cutter driving device for an underground excavator capable of obtaining a cutter torque with a small fluctuation in torque generated by a driving jack and efficiently obtaining the cutter torque. It is in.

[0020]

According to the present invention, there is provided a method for controlling a driving jack comprising a cylinder, a piston, and a piston rod, the method comprising the steps of: The pressure of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder is controlled so that the pushing force and the retraction force of the piston rod become substantially the same.

In the method of controlling a driving jack according to the present invention, the piston rod is supplied to the piston head chamber side and the piston rod chamber side in the cylinder so that the pushing speed and the retraction speed of the piston rod are substantially the same. The flow rate of the working fluid is controlled.

In the method for controlling a driving jack according to the present invention, the piston rod is supplied to the piston head chamber side and the piston rod chamber side in the cylinder such that the pushing force and the retracting force of the piston rod become substantially the same. In addition to controlling the pressure of the hydraulic fluid, the flow rate of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder is controlled so that the pushing speed and the retraction speed of the piston rod become substantially the same. Like that.

According to another aspect of the present invention, there is provided a control circuit for a driving jack having a cylinder, a piston, and a piston rod and being operated by hydraulic pressure. A possible direction switching valve is connected by a power passage, the direction switching valve is connected to the piston head chamber side in the cylinder of the driving jack by an approach path, and the same direction switching valve is connected to the piston rod chamber side in the cylinder. In the control circuit of the driving jack connected by the return passage, a first relief valve is provided in the power passage, a second relief valve is provided in the approach passage, and the first and second relief valves provide The piston rod is supplied to the piston head chamber side and the piston rod chamber side in the cylinder so that the pushing force and the retraction force of the piston rod are almost the same. It is capable of controlling the pressure of the hydraulic fluid.

In the control apparatus for a driving jack according to the present invention, a first one-way flow control circuit comprising a check valve and a flow control valve is provided in the approach passage, and a reverse flow control circuit is provided in the return passage. A second one-way flow control circuit comprising a combination of a stop valve and a flow control valve is provided, and the first and second one-way flow control circuits make the push-out speed and the retraction speed of the piston rod substantially the same. Thus, the flow rate of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder can be controlled.

In the control apparatus for a driving jack according to the present invention, a first relief valve is provided in the power passage, and a second relief valve is provided in the approach passage.
The pressure of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder is controlled by the first and second relief valves so that the pushing force and the retraction force of the piston rod become substantially the same. While being configured to be controllable, a first one-way flow control circuit including a check valve and a flow control valve is provided in the approach passage,
The return passage is provided with a second one-way flow control circuit which is a combination of a check valve and a flow control valve.
The flow rate of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder is controlled by the second one-way flow control circuit so that the pushing speed and the retraction speed of the piston rod are substantially the same. It is configured to be possible.

Further, in the cutter driving method for an underground excavator according to the present invention, the crank is rotated by a driving jack having a cylinder, a piston and a piston rod and operated by hydraulic pressure, directly or via a driving jack connecting member. In the cutter driving method of the underground excavator for excavating the ground by rotating the cutter rotating shaft by the crank and rotating the cutter by the cutter rotating shaft, (1) the pushing force and the retracting force of the piston rod are almost equal to each other. Controlling the pressure of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder so as to be the same, (2)
Controlling the flow rate of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder so that the pushing speed and the retraction speed of the piston rod are substantially the same; (3) The pressure of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder is controlled so that the pushing force and the retraction force become substantially the same, and the pushing speed and the retraction speed of the piston rod are adjusted. The above (1), (2) or (3) of controlling the flow rate of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder so as to be substantially the same is adopted. .

In the cutter driving device for an underground excavator according to the present invention, the crank is rotated by a driving jack having a cylinder, a piston and a piston rod and operated by hydraulic pressure, either directly or via a driving jack connecting member. In the cutter driving device of the underground excavator that excavates the ground by rotating the cutter rotating shaft by the crank and rotating the cutter by the cutter rotating shaft, (4) the power passage in the control circuit of the driving jack includes: A first relief valve is provided in the approach passage, and a second relief valve is provided in the approach passage. The first and second relief valves are arranged so that the pushing force and the retraction force of the piston rod become substantially the same. (5) the pressure of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the inside can be controlled. A first one-way flow control circuit comprising a check valve and a flow control valve in the return passage, and a second one-way flow circuit comprising a check valve and the flow control valve in the return passage. A flow control circuit is provided, and the piston head chamber side and the piston rod chamber side in the cylinder are controlled by the first and second one-way flow control circuits so that the pushing speed and the retraction speed of the piston rod are substantially the same. And (6) a first relief valve is provided in the power passage, and a second relief valve is provided in the approach passage. The pressure of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder can be controlled by the relief valve 2 so that the pushing force and the retraction force of the piston rod are almost the same. And a first one-way flow control circuit combining a check valve and a flow control valve is provided in the approach passage, and a check valve and a flow control valve are combined in the return passage. A second one-way flow control circuit is provided, and the first and second one-way flow control circuits are arranged so that the pushing speed and the retraction speed of the piston rod are substantially the same. (4), (5) or (6), wherein the flow rate of the working fluid supplied to the piston rod chamber and the piston rod chamber can be controlled.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a control circuit for implementing the method of controlling a driving jack according to the present invention, and FIG. 2 shows a state in which the control circuit shown in FIG. 1 is operated in a direction in which a piston rod is pushed out. FIG. 3 shows a state where the piston rod is operated in the retracting direction in the control circuit.

In the embodiment shown in FIGS. 1, 2 and 3, the drive jack 1 is controlled by the control circuit 13.

The drive jack 1 has a cylinder 2, a piston 3, and a piston rod 4 as shown in FIG. When the pressure receiving area on the piston head side of the piston 3 is A ₁ , the pressure receiving area on the piston rod side is A ₂ , and the cross-sectional area of the piston rod is a, A ₁ , A ₂ and a are A ₁ = A ₂ + a.

On the other hand, in the control circuit 13, a power unit is constituted by a hydraulic pump 14, which is a hydraulic pressure source of hydraulic fluid, a hydraulic fluid tank 15, and a direction switching valve 18.

In this embodiment, a three-position switching valve which can be switched to the a, b, c (neutral) positions is used as the direction switching valve 18.

A of the hydraulic pump 14 and the directional control valve 18
The port is connected by a power passage 16, and the B port of the direction switching valve 18 and the tank 15 are connected by a return passage 17.

The port A of the directional control valve 18 and the piston head chamber side of the cylinder 2 of the driving jack 1 are connected by an approach passage 19. On the other hand, the B port of the direction switching valve 18 and the piston rod chamber side of the driving jack 1 in the cylinder 2 are connected by a return passage 20.

The power passage 16 is provided with a first relief valve 21. In addition, the approach passage 1
9 is provided with a second relief valve 22 on its upstream side.

Further, a first one-way flow control circuit 23 is provided in the approach passage 19 downstream of the second relief valve 22. The first one-way flow control circuit 23 is configured by combining a check valve 25 and a flow control valve 27 connected in parallel with the check valve 25. The return passage 20 includes a second one-way flow control circuit 24.
Is provided. This second one-way flow control circuit 24
Also has a check valve 26 and a flow control valve 2 connected in parallel with the check valve 26.
8 in combination.

Next, an example of the driving jack control method according to the present invention will be described with reference to the operation of the driving jack control circuit 13.

First, the working fluid discharged from the hydraulic pump 14 of the control circuit 13 of the driving jack is always supplied to the pressure P ₁ by the first relief valve 21 provided in the power passage 16.
Is set to

Here, when the control circuit 13 of the driving jack operates the piston rod 4 in the pushing direction, the direction switching valve 18 is switched from the position C in FIG. 1 to the position A as shown in FIG.

As described above, when the directional control valve 18 is switched to the a position, as can be seen from FIG. 2, the hydraulic fluid is sent from the A port of the directional control valve 18 to the approach passage 19, and the first one-way flow control is performed. The piston enters the piston head chamber side of the cylinder 2 of the drive jack 1 through the flow control valve 27 of the circuit 23, pushes the piston 3, and pushes out the piston rod 4.

At this time, the working fluid supplied to the piston head chamber side in the cylinder 2 is controlled to the pressure P ₂ by the second relief valve 22 and the flow control valve of the first one-way flow control circuit 23. It is controlled to a flow rate _{Q 1} by 27.

The hydraulic fluid entering the piston rod chamber in the cylinder 2 of the driving jack 1 flows out to the return passage 20, and the check valve 26 of the second one-way flow control circuit 24 → the direction switching valve. The port 18 is returned to the tank 15 through the return passage 17.

Thus, the pressure P ₂ (where P ₂ <P
_1), by being controlled in flow rate Q ₁ hydraulic fluid supplied to the piston head chamber side in the cylinder 2 piston 3 is pushed, the piston rod 4 due to this is pushed out by the pushing force F, the extrusion rate V.

Next, when the piston rod 4 is operated in the retracting direction by the control circuit 13 of the driving jack, the direction switching valve 18 is switched to the position B as shown in FIG.

As described above, when the directional control valve 18 is switched to the position B, the hydraulic fluid is supplied from the B port of the directional control valve 18 to the return passage 20, as can be seen from FIG.
Through the flow control valve 28 of the second one-way flow control circuit 24, the drive jack 1 enters the piston rod chamber side in the cylinder 2 of the drive jack 1, pushes the piston 3, and retracts the piston rod 4.

At this time, the working fluid supplied to the piston rod chamber side in the cylinder 2 has the pressure P ₁ controlled by the first relief valve 21 and the flow rate of the second one-way flow control circuit 24. It is controlled to a flow rate _{Q 2} by control valve 28.

On the other hand, the working fluid entering the piston head chamber side of the cylinder 2 of the driving jack 1 flows out to the approach passage 19 and the check valve 25 of the first one-way flow control circuit 23 → direction switching valve. The port 18 is returned to the tank 15 through the return passage 17.

Thus, the pressure P₁(However, P₁> P
₂), Flow rate Q₂(However, Q₂<Q ₁) Controlled by
Hydraulic fluid supplied to the piston rod chamber side in the cylinder 2
The piston 3 is pushed by the
Is drawn in at a drawing force F 'and a drawing speed V'.

The drive jack control circuit 1
In 3, the pressure P ₂ of the working fluid supplied to the piston head chamber side in the cylinder 2 is controlled by the second relief valve 22, and the pressure P ₁ of the working fluid supplied to the piston rod chamber side in the cylinder 2 is controlled to the first pressure. Control is performed by the relief valve 21 so that the following equations are satisfied. P ₁ A ₂ = P ₂ A ₁ = F = F 'where F: pushing force of piston rod F': pulling force of piston rod

FIG. 10 shows one cycle when the drive jack 1 is controlled by the drive jack control circuit 13 according to the present embodiment and the reciprocating linear motion of the piston rod 4 is converted into rotary motion via a crank mechanism. FIG.

As can be seen from FIG. 10 and Equation 2, by controlling the hydraulic fluid pressures P ₁ and P _{2 so} that the pushing force F and the retraction force F ′ of the piston rod 4 become the same, 1 The peak height of the torque in the cycle, that is, the maximum torque T can be made the same. Therefore, the crank mechanism can be smoothly rotated.

The drive jack control circuit 13
Now, the operation to supply to the piston head chamber side in the cylinder 2
Liquid flow rate Q₁Of the first one-way flow control circuit 23
By the control valve 27 and the piston rod chamber in the cylinder 2
Flow rate Q of hydraulic fluid supplied to the side ₂To the second one-way flow control
The following equations are respectively formed by the flow control valves 28 of the circuit 24.
Control to stand up. Q₁A₂= Q₂A₁= V = V 'where V is the piston rod extrusion speed V' is the piston rod retraction speed

[0054] Thus, the flow rate to Q ₁ hydraulic fluid supplied to the piston head chamber side in the cylinder 2, and a flow rate Q ₂ of the hydraulic fluid supplied to the piston rod chamber side in the cylinder 2 of the piston rod 4 Extrusion Speed V and piston rod 4
Is controlled so that the retracting speed V 'of the piston rod 4 becomes the same, so that the pushing speed V of the piston rod 4 differs from the retracting speed V' in a specification in which the crank mechanism is rotated by a plurality of drive jacks 1, for example. As a result, it is possible to solve the problem that the brake is applied to the crank mechanism, and it is possible to rotate the crank mechanism smoothly and efficiently.

In the drive jack control circuit 13 in this embodiment, a second relief valve 22 is provided.
When the flow control valves 27 and 28 of the first and second one-way flow control circuits 23 and 24 are omitted, the pushing force F and the retraction force F ′ of the piston rod 4 can be set to F = F ′. The pushing speed V and the retraction speed V ′ of the piston rod 4 are V ≠ V ′.

On the other hand, the first and second one-way flow control circuits 2
When the flow control valves 27 and 28 are provided in the third and the 24th and the second relief valve 22 is omitted, the pushing speed V and the retraction speed V ′ of the piston rod 4 can be set to V = V ′. 4, the pushing force F and the retraction force F '.
Becomes F ≠ F ′.

The direction switching valve 18 of the drive jack control circuit 13 is not limited to the three-position switching valve of the embodiment shown in the drawing, but may be a two-position switching valve capable of switching between the a position and the b position. You may.

FIG. 4 is a rear view showing an embodiment of an underground excavator employing a drive jack control method and a control circuit according to the present invention, and FIG. 5 is a vertical sectional side view of FIG.

The shield machine 33, which is an underground excavator shown in FIGS. 4 and 5, includes a shield cylinder 34, a partition wall 35, a hood 36, a cutter 37, and first cranks 40a to 40a.
0d, cutter rotating shafts 43a to 43d, second cranks 46a to 46d, and a plurality (four) of driving jacks 1
a to 1d and drive jack control circuits 13a to 13d
A sensor (not shown) for detecting the stroke of the drive jacks 1a to 1d or the rotation angle of the crank, and a control circuit 13 for the drive jack based on the detection result of the sensor.
A controller (not shown) for sending commands to a to 13d, a chamber 51 for excavated earth and sand, a screw conveyor 52 which is a device for discharging the excavated earth and sand, and a plurality of shield jacks 53 are provided. The shield machine 33 further includes a tail seal, an additive injection unit, a backfill injection unit, and the like, but these members are omitted in the drawing.

The cutter 37 includes a cutter frame 38.
And a number of cutter bits 39 provided on the front surface thereof.

Each of the first cranks 40a to 40d has a crank arm 41 and a crank shaft 42.
Each of the first cranks 40 a to 40 d is fixed to the back surface of the cutter frame 38 via the crank shaft 42.

The cutter rotation shafts 43a to 43d are
Crank pins of the cranks 40a to 40d of the second
Are the crankshafts of the cranks 46a to 46d. Each of the cutter rotating shafts 43a to 43d is rotatably supported by a bearing 45 provided on a partition wall 35 and a crank bearing plate 44 attached to the partition wall 35.

Each of the second cranks 46 a to 46 d has a crank arm 41 and a crank pin 48. Each of the second cranks 46a to 46d is provided with a crank arm 4 at an input end of each of the cutter rotating shafts 43a to 43d.
1 are connected at right angles.

The driving jacks 1a to 1d are similar to the driving jack 1 shown in FIGS.
It has a piston (omitted in FIGS. 4 and 5) and a piston rod 4. The end of the drive jacks 1a to 1d on the cylinder side is pivotally supported by the bracket 49 fixed to the inner periphery of the shield tube 34 via a mounting pin 50, and the end of the piston rod is connected to the second crank. 46
a to 46d of crank pins 48.

Control circuits 13a to 13 for the driving jack
3d, the control circuit 13a includes a hydraulic pump 14, which is a hydraulic pressure source, a tank 15, a direction switching valve 18, and a A power passage 16 connecting the switching valve 18 and the tank 15
A return passage 17 for the hydraulic fluid connecting the directional control valve 18 to the piston head chamber in the cylinder 2 of the drive jack 1a and the A port of the directional control valve 18; a cylinder of the drive jack 1a 2, a return passage 20 connecting the piston rod chamber side to the B port of the direction switching valve 18, a first relief valve 21 provided in the power passage 16, and the approach passage 19.
A first one-way flow control circuit 23 which is configured by combining a second relief valve 22 provided in the
And a second one-way flow control circuit 24 configured by combining another check valve 26 and a flow control valve 28 and provided in the return passage 20.

The drive jack control circuits 13b-1
3d is a power passage 16, a return passage 17, a direction switching valve 18, an approach passage 19 connecting the A port of the direction switching valve 18 and the piston head chamber side in the cylinder 2 of the driving jacks 1b to 1d, A return passage 20 connecting the piston rod chamber side of the drive jacks 1 b to 1 d in the cylinder 2 to the B port of the direction switching valve 18.
A second relief valve 22 provided in the approach passage 19, a check valve 25 and a flow control valve 27, and a first relief valve 22 provided in the approach passage 19.
One-way flow control circuit 23, another check valve 26 and flow control valve 28, and
0, and a second one-way flow control circuit 24 provided at the first position. And the control circuits 13b to 13b
d, the power path 16 is the power path 1 of the control circuit 13a.
6 is connected between the first relief valve 21 and the direction switching valve 18. Further, the control circuits 13b to 13d
The return passage 17 is connected to the return passage 17 of the control circuit 13a. That is, in this embodiment, the power unit and the first relief valve 21 are shared by the control circuits 13a to 13d.

In the shield machine 33 of this embodiment, the driving jacks 1a to 1a are controlled by sensors (not shown).
Detects 1d stroke or crank rotation angle,
The detection result is sent to a controller (also not shown).

The controller switches between pushing and pulling of the driving jacks 1a to 1d near the top dead center and bottom dead center of the driving jacks 1a to 1d based on the detection result from the sensor. A command is sent to the control circuits 13a to 13d of the driving jack in order to control so that a plurality of pushes and pulls by .about.1d overlap.

Here, the drive jack control circuits 13a to 13a
The direction switching valve 18 of 13d is switched to the a or b position, and in the state of FIG.
At the top dead center, the drive jack 1b attempts to switch from pull to push by the control by the control circuit 13b.
Is controlled by the control circuit 13c, the drive jack 1c attempts to switch from pushing to pulling at the bottom dead center, and the driving jack 1d
Is in a pressed state by the control of the control circuit 13d.

As described above, the driving jack control circuit 1
3a to 13d, the push and pull of the drive jacks 1a to 1d are controlled so as to overlap with each other, and in this embodiment, each of the control circuits 13a to 13d is controlled by the first and second relief valves 21 and 22 respectively. In each of the driving jacks 1a to 1d, the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder 2 is set so that the pushing force F and the retraction force F 'of the piston rod 4 become F = F'. The pressures P ₁ and P ₂ are controlled. Further, the control circuit 13
a to 13d first and second one-way flow control circuits 23 and 2
The piston head chamber in the cylinder 2 is controlled by the flow control valves 27 and 28 provided in the cylinder 2 so that the pushing speed V and the retraction speed V 'of the piston rod 4 of each of the driving jacks 1a to 1d are V = V'. The flow rates Q ₁ and Q _{2 of the} hydraulic fluid supplied to the side and the piston rod chamber side are controlled.

As described above, the second jacks 46a to 46d are rotated by the driving jacks 1a to 1d controlled so that a plurality of pushing and pulling operations are overlapped, and the rotation is performed by the cutter rotating shafts 43a to 43d and the first rotating shafts 43a to 43d. Crank 4
0a to 40d, and the cutter 37 rotates.

A rotary force is applied to the cutter 37, a thrust is applied to the cutter 37 by the shield jack 53, and the ground is excavated by a number of cutter bits 39 provided on the front surface of the cutter frame 38.

The excavated earth and sand is taken into the chamber 51,
The inside of the chamber 51 is maintained at a predetermined pressure by the taken excavated earth and sand, and the excavated earth and sand is taken in from the chamber 51 by the screw conveyor 52 while preventing collapse of the face,
Discharge.

After excavating the ground in a predetermined area, the shield jack 53 is reduced and the shield cylinder 34 is removed.
At the rear part, a segment (not shown) is assembled, the shield jack 53 is extended by applying a reaction force to the segment, and the entire shield machine 33 is propelled.

The above operation is repeated to excavate the tunnel.

FIG. 12 is a torque diagram of the four driving jacks according to the present invention. The lower part of FIG. 12 shows the fluctuation of the torque generated by the four driving jacks in one cycle, and the upper part of FIG. 3 shows the combined torque of a drive jack of a book.

FIG. 13 is a torque diagram according to the prior art. The lower part of FIG. 13 shows the fluctuation of the torque generated by the four drive jacks in one cycle, and the upper part shows the combined torque of the four drive jacks. Is shown.

In the prior art, no consideration is given to equalizing the pushing force and the retracting force of the piston rod in the driving jack, and equalizing the pushing speed and the retracting speed of the piston rod. As a result, the difference between the pushing force and the retracting force of the piston rod,
Depending on the difference between the pushing speed and the retracting speed of the piston rod, a plurality of drive jacks act to reduce the torque or act to brake the other drive jacks.

For this reason, in the prior art, as can be seen from FIG. 13, the fluctuation of the combined torque of the four drive jacks was large, and a smooth and efficient torque could not be obtained.

On the other hand, in the embodiment shown in FIGS. 4 and 5 of the present invention, the pushing force F and the retraction force F 'of the piston rod 4 are the same for all four driving jacks 1a to 1d. The pressures P ₁ and P ₂ of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder 2 are controlled so that the pushing speed V and the retraction speed V ′ of the piston rod 4 are the same. The flow rates Q ₁ and Q ₂ of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder 2 are controlled.

As a result, as can be seen from FIG. 12, the fluctuation of the combined torque of the four drive jacks 1a to 1d is extremely small, and a smooth and efficient torque can be obtained. Therefore, since the cutter 37 can be rotated with a stable large torque, it is possible to excavate the ground with a stable large excavation force.

In the embodiment shown in FIGS. 4 and 5 of the present invention, the pushing force F and the retraction force F 'of the piston rod 4 in the driving jacks 1a to 1d are controlled so as to be equal to each other. Even if the pushing speed V and the retraction speed V 'of the rod 4 are controlled to be the same, an appropriate action and effect can be obtained in reducing the combined torque of the four drive jacks 1a to 1d.

FIG. 6 is a rear view showing another embodiment of the underground excavator employing the control method and control circuit of the driving jack according to the present invention.

In the embodiment shown in FIG. 6, a drive jack connecting plate 54, which is a drive jack connecting member, is commonly attached to the four crank pins 48 of the second cranks 46a to 46d.

The drive jack connecting plate 54 is connected to the piston rod side ends of the drive jacks 1 a to 1 d by connecting pins 5.
5 are connected.

In the embodiment shown in FIG. 6, the drive jack connecting plate 54 is formed by four drive jacks 1a to 1d.
And the rotation is applied to the second cranks 46a to 46d.
→ cutter rotating shafts 43a to 43d → first crank 40a
The light is transmitted to the cutter 37 through ４０40 d to rotate the cutter 37.

The other structure and operation of the embodiment shown in FIG. 6 are the same as those of the embodiment shown in FIGS. 4 and 5.

In the present invention, the number of the first cranks,
The number of cutter rotating shafts, the number of second cranks, the number of drive jacks, the number of control circuits, and the like are not limited to the embodiment shown in the drawings, and may be, for example, three or three, or five or five. Or more.

In the embodiment shown in FIG. 6, the number of second cranks and the number of drive jacks may be different.

Further, in the present invention, as in the embodiments shown in FIGS. 4 and 5 and the embodiment shown in FIG. 6, not only a multi-axial shield having a plurality of cutter rotating shafts but also a single-axial shield is adopted. can do.

FIG. 7 is a circuit diagram showing another embodiment of the drive jack control circuit according to the present invention.

The embodiment shown in FIG. 7 differs from the embodiment shown in FIG. 1 in the configuration of the first one-way flow control circuit 23.

That is, in the first one-way flow control circuit 23 in the embodiment shown in FIG.
a, 25b, and two check valves 25c, 25c,
A series circuit of 25d and a circuit having one check valve 25e are connected in parallel with each other. In addition, the check valve 2
5a, 25b and a series circuit having check valves 25c, 25c.
The flow control valve 27 is connected between the series circuits having d.

In the embodiment shown in FIG. 7, the hydraulic fluid is supplied to the piston rod chamber side in the cylinder 2 and the hydraulic fluid entering the piston head chamber side in the cylinder 2 in the mode in which the piston rod 4 is retracted. Is returned to the tank 15 via the check valve 25b → the flow control valve 27 → the check valve 25c of the first one-way flow control circuit 23, and is returned to the tank 15 via the other check valve 25e. As a result, when the back pressure is generated by the return side hydraulic fluid being throttled by the flow control valve 27, the back pressure can be released through the check valve 25e.

The other structure and operation of the embodiment shown in FIG. 7 are the same as those of the embodiment shown in FIG.

[0096]

As described above, in the control method and the control device of the driving jack according to the present invention, the piston head in the cylinder is so controlled that the pushing force and the retraction force of the piston rod of the driving jack are substantially the same. Since it is configured to control the pressure of the hydraulic fluid supplied to the chamber side and the piston rod chamber side, for example, when the rotating body is rotated by a plurality of drive jacks, a plurality of rotations in one cycle are performed. The fluctuation of the synthetic torque due to the drive jack can be reduced, so that it is smooth,
Moreover, there is an effect that an efficient torque can be obtained.

Further, in the control method and the control device for the driving jack according to the present invention, the piston head chamber side and the piston rod chamber side in the cylinder are controlled so that the pushing-out speed and the retraction speed of the piston rod of the driving jack become substantially the same. Since the configuration is such that the flow rate of the hydraulic fluid supplied to the side is controlled, in the present invention, for example, when the rotating body is rotated by a plurality of driving jacks, a plurality of driving jacks are used in one cycle. Thus, there is an effect that the fluctuation of the combined torque due to the driving jack can be reduced, so that a smooth and efficient torque can be obtained.

Further, in the control method and the control circuit of the drive jack according to the present invention, the piston head chamber side and the piston rod chamber in the cylinder are controlled so that the pushing force and the retraction force of the piston rod of the drive jack become substantially the same. The hydraulic fluid is supplied to the piston head chamber side and the piston rod chamber side in the cylinder so that the push-out speed and the retraction speed of the piston rod of the drive jack are almost the same as well as the pressure of the hydraulic fluid supplied to the side. Since the configuration is such that the flow rate of the hydraulic fluid is controlled, in the present invention, for example, when the rotating body is rotated by a plurality of drive jacks, the synthesis by the plurality of drive jacks in one cycle is performed. Torque fluctuations can be significantly reduced, thus obtaining a smoother and more efficient torque There is an effect that theft can be.

Further, according to the cutter driving method and the driving apparatus for an underground excavator according to the present invention, the control method and the control circuit for the driving jack according to the present invention are employed, and the plurality of driving jacks are used for the piston rod. The pushing force and the retraction force are almost the same, or the pushing speed and the retraction speed of the piston rod are almost the same, or the pushing force and the retraction force of the piston rod are almost the same, and the piston rod Since the control is performed so that the extrusion speed and the retraction speed are almost the same, the fluctuation of the synthetic torque by the plurality of drive jacks is small, and the cutter is rotated with a stable and efficient cutter torque, It has the effect of excavating the ground.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of a drive jack control circuit according to the present invention.

FIG. 2 is a circuit diagram showing a state in which a piston rod of a driving jack is operated in a pushing direction by a control circuit shown in FIG. 1;

FIG. 3 is a circuit diagram showing a state in which a piston rod of a driving jack is operated in a retracting direction by a control circuit shown in FIG. 1;

FIG. 4 is a rear view showing an example of a shield machine which is an underground excavator in which the control circuit of the drive jack shown in FIG. 1 is employed in a cutter driving device.

FIG. 5 is a vertical sectional side view of FIG. 4;

FIG. 6 is a rear view showing another example of a shield machine which is an underground excavator in which the control circuit of the drive jack shown in FIG. 1 is employed in a cutter driving device.

FIG. 7 is a circuit diagram showing another embodiment of the drive jack control circuit according to the present invention.

FIG. 8 is a schematic view of a drive jack according to the present invention.

FIG. 9 is an explanatory diagram of a crank mechanism that converts a reciprocating linear motion of a piston rod of a driving jack into a rotary motion.

FIG. 10 is a torque diagram when the drive jack is controlled by the drive jack control circuit according to the present invention and the rotating body is rotated once.

FIG. 11 is a torque diagram when the driving jack is controlled by the conventional technique and the rotating body is rotated once.

FIG. 12 is a torque diagram when four drive jacks are controlled by the drive jack control circuit according to the present invention.

FIG. 13 is a torque diagram when four drive jacks are controlled according to the related art.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Drive jack 2 Cylinder of drive jack 3 Piston of drive jack 4 Piston rod of drive jack A ₁ Pressure receiving area of piston head side of ₁ piston A ₂ Pressure receiving area of piston rod side of piston a Piston rod cross-sectional area 13 Control of drive jack Circuit 14 Hydraulic pump 15 Tank 16 Power passage 17 Return passage to tank 18 Direction switching valve 19 Approach passage 20 Return passage 21,22 First and second relief valve 23,24 First and second one-way flow control circuit 25,25a~25e, 26 a check valve 27, 28 flow control valve P _{1, P 2} hydraulic fluid pressure Q _{1, Q 2} hydraulic fluid flow F piston rod pushing force F 'piston rod of the retraction force V piston of Rod extrusion speed V 'Piston rod retraction speed 3 Underground excavator 34 Shield cylinder 35 Partition wall 37 Cutter 40a to 40d First crank 43a to 43d Cutter rotation axis 46a to 46d Second crank 1a to 1d Drive jack 13a to 13d Control circuit of drive jack 51 Chamber for excavated earth and sand 52 Screw conveyor as earth removal device 53 Shield jack 54 Drive jack connecting plate as drive jack connecting member

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 2D054 AC01 BA03 BB09 DA03 GA23 GA33 GA38 GA62 GA65 GA81 3H089 AA29 BB15 CC01 DA02 DB03 DB13 DB33 DB46 DB49 GG02 JJ01

Claims (8)

[Claims] 1. A method for controlling a hydraulically operated drive jack having a cylinder, a piston, and a piston rod, wherein a piston and a piston in the cylinder are arranged so that the pushing force and the retraction force of the piston rod are substantially the same. A method for controlling a driving jack, comprising controlling pressure of a hydraulic fluid supplied to a head chamber side and a piston rod chamber side. 2. A method for controlling a hydraulically actuated drive jack having a cylinder, a piston, and a piston rod, wherein a piston in the cylinder is controlled so that a pushing speed and a retraction speed of the piston rod are substantially the same. A method for controlling a drive jack, comprising: controlling a flow rate of a hydraulic fluid supplied to a head chamber side and a piston rod chamber side. 3. A method for controlling a hydraulically actuated drive jack having a cylinder, a piston and a piston rod, wherein the piston and the piston in the cylinder are arranged so that the pushing force and the retraction force of the piston rod are substantially the same. The pressure of the hydraulic fluid supplied to the head chamber side and the piston rod chamber side is controlled, and the piston head chamber side and the piston rod chamber in the cylinder are controlled so that the pushing speed and the retraction speed of the piston rod are substantially the same. A method for controlling a drive jack, comprising: controlling a flow rate of a working fluid supplied to a side of a driving jack. 4. A control circuit for a hydraulically actuated drive jack having a cylinder, a piston, and a piston rod, wherein a hydraulic pressure source and a direction switching valve switchable to at least two positions are connected by a power passage. In the control circuit of the driving jack, the direction switching valve and the piston head chamber side in the cylinder of the driving jack are connected by an approach path, and the direction switching valve and the piston rod chamber side in the cylinder are connected by a return path. A first relief valve is provided in the power passage, a second relief valve is provided in the approach passage, and the pushing force and the retraction force of the piston rod are substantially reduced by the first and second relief valves. The pressure of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder can be controlled so that they are the same. The control circuit of power jack that. 5. A control circuit for a hydraulically operated drive jack having a cylinder, a piston and a piston rod, wherein a hydraulic pressure source and a directional control valve switchable to at least two positions are connected by a power passage. In the control circuit of the driving jack, the direction switching valve and the piston head chamber side in the cylinder of the driving jack are connected by an approach path, and the direction switching valve and the piston rod chamber side in the cylinder are connected by a return path. A first one-way flow control circuit combining a check valve and a flow control valve is provided in the approach passage; a second one-way flow control circuit combining a check valve and a flow control valve is provided in the return passage; A direction flow control circuit is provided, and the first and second one-way flow control circuits are configured so that the pushing speed and the retraction speed of the piston rod are substantially the same. Was capable of controlling the flow rate of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder, the control circuit of the power jack, characterized in that. 6. A control circuit for a hydraulically actuated drive jack having a cylinder, a piston and a piston rod, wherein a hydraulic pressure source and a direction switching valve switchable to at least two positions are connected by a power passage. In the control circuit of the driving jack, the direction switching valve and the piston head chamber side in the cylinder of the driving jack are connected by an approach path, and the direction switching valve and the piston rod chamber side in the cylinder are connected by a return path. A first relief valve is provided in the power passage, a second relief valve is provided in the approach passage, and the pushing force and the retraction force of the piston rod are substantially reduced by the first and second relief valves. The pressure of the hydraulic fluid supplied to the piston head chamber side and the piston rod chamber side in the cylinder is configured to be controllable so that they are the same. A first one-way flow control circuit comprising a check valve and a flow control valve is provided in the approach passage, and a second one-way flow control circuit comprising a check valve and a flow control valve is provided in the return passage. A control circuit is provided, and the piston head chamber side and the piston rod chamber side in the cylinder are controlled by the first and second one-way flow control circuits so that the pushing speed and the retraction speed of the piston rod are substantially the same. A control circuit for a drive jack, characterized in that the flow rate of the hydraulic fluid supplied to the vehicle can be controlled. 7. A crank having a cylinder, a piston, and a piston rod, and rotated by a hydraulically operated drive jack, directly or via a drive jack connecting member,
A cutter driving method of an underground excavator for excavating a ground by rotating a cutter rotating shaft by a crank and rotating a cutter by a cutter rotating shaft, wherein the driving jack is driven by the control method according to claim 1, 2, or 3. A method for driving a cutter of an underground excavator, comprising controlling the cutter. 8. A crank having a cylinder, a piston, a piston rod, and a hydraulically actuated drive jack for rotating a crank directly or via a drive jack connecting member;
A cutter driving device for an underground excavator that excavates a ground by rotating a cutter rotating shaft by a crank and rotating a cutter by a cutter rotating shaft, wherein the drive jack is controlled by the control circuit according to claim 4, 5, or 6. A cutter driving device for an underground excavator, characterized by controlling.