JPS60119897A - Oil pressure apparatus of gripper jack in tunnel drilling machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a gripper jack for a tunnel excavator that presses a gripper vertically against a tunnel wall and takes a reaction force to the frictional force to obtain propulsive force for the excavator main body. The present invention relates to a hydraulic system.

Generally, as shown in FIGS. 1 and 2, a tunnel excavating machine has a plurality of self-propelled jacks 2 interposed between a tunnel excavating machine main body 100 and a square tubular gripper support 500, and the grit A gripper jack 7 is fixed to four sides of the support body 500, and a gripper 6 is fixed to the tip of the piston rod of the gripper jack 7. Next, the operating pressure will be explained.

First, the gripper jack 7 is extended to press the gripper 6 against the wall of the tunnel, and a reaction force is taken from the frictional force. Next, the self-propelled jack 2 is extended and the tunnel excavator main body 10 is
Advance 0. Then, the gripper jack 7 is retracted to release the gripper 6 from the tunnel wall, and the self-propelled jack 2 is retracted to release the gripper support 500. gripper jack 7
Then, the gripper 6 is drawn toward the tunnel excavator main body ioo.

Thereafter, the above-mentioned operations are repeated to dig the tunnel.

The hydraulic circuit of a conventional gripper jack in such a tunnel excavator will be explained with reference to FIG.

This hydraulic circuit connects a main switching valve 11 that switches the expansion and contraction of the hydraulic pump PK gripper jack 7, and connects hydraulic pipes 18, 15, and 14 from the main switching valve 11 to the bottom side and rod side of the gripper jack 7, respectively. Connecting.

A selection changeover valve 8 for selecting the gripper jack desired to be used is provided in the middle of the hydraulic piping 15 on the bottom side. In the figure, T
1 is an oil tank, and 12 and 13 are check valves and IJ valves for overload prevention. Next, the operation will be explained. When the main switching valve 11 is switched from the neutral port to the A port and the selection switching valve 8 of the gripper jack to be extended is opened, pressure oil from the hydraulic pump P is transferred to the gripper jack 7.
The piston rod of the gripper jack 7 extends. Next, when the main switching valve 11 is switched to the B port, pressure oil is supplied to the rod side of the gripper jack 7, and the piston rod of the gripper jack 7 is retracted. However, the above-mentioned conventional gripper jack hydraulic circuit allows the gripper jack 7 to extend and retract.
Since this is done individually, the distribution of the pressing force of the gripper jack 7 varies and it is not possible to maintain the same load balance as at the beginning. For example, if there is a soft part in the mine wall 3 where the gripper 6 touches the ground, that soft ground will cave in and only the gripper jack 7 in that part will stretch too much, disrupting the load balance and causing the pit wall 6 to collapse. There are drawbacks.

The present invention aims to provide a hydraulic system for a gripper jack in tunnel excavation m which improves the above-mentioned drawbacks.

The present invention divides a plurality of clipper jacks into a first group that supports the weight of the gripper support and a second group that does not support the weight of the gripper support, and connects a hydraulic circuit connecting a hydraulic power source and the gripper jacks to the first group. A first on-off switching valve and a second on-off switching valve that branch into a first hydraulic circuit for the group and a second hydraulic circuit for the second group, and independently open and close the first hydraulic circuit and the second hydraulic circuit. and, respectively,
The present invention is characterized in that a selection switching valve for selecting the gripper jack to be used is interposed between the first on-off switching valve and the second on-off switching valve and the plurality of gripper jacks.

Hereinafter, two of the embodiments of the hydraulic system for the brake and pajack in the tunnel excavator of the present invention will be described with reference to FIGS. 4 to 7.

4 and 5 are longitudinal cross-sectional views of a tunnel excavator equipped with a hydraulic system and a gripper jack according to the present invention.
It is a sectional view taken along the line V-V in the figure.

This tunnel excavation machine has a rear part 1a of a small diameter part of a tunnel excavation machine main body 1 having a cylindrical shape, and an inner diameter of the rear part 11LO.
A ring-shaped gripper support 5 larger than the outer diameter is fitted onto the outside so as to be movable in the axial direction, and an upper self-propelled jack 2b and a lower self-propelled jack 2a are installed between the gripper support 5 and the tunnel excavator main body 1. intervene. A lower gripper 6a and an upper gripper 6 are provided at the lower and upper parts of the gripper support 5.
6 b are supported so as to be movable in the radial direction of the tunnel and the gripper support 5, and between the lower gripper 6a and the upper gripper 6b and the gripper support 5, a lower gripper jack 7a and an upper gripper jack 7b are installed. It is interposed so that the direction of expansion and contraction of 7a and 7b matches the radial direction of the tunnel. In addition, the reference numeral 4 in the figure is a lining body that prevents the collapse of the shaft wall 6.

As shown in FIG. 6, the hydraulic circuit of the gripper jack of the present invention in this embodiment has six gripper jacks connected to the lower six gripper jacks 7a that support the weight of the gripper support 5, and the gripper support 5. The gripper jacks 7b are divided into six upper gripper jacks 7b that do not support the weight of the gripper. Hydraulic pipes connecting the main switching valve 11 and the bottom sides of the gripper jacks 7a, 7b are connected to first hydraulic pipes 19a, 15a for the lower gripper jacks 7a and second hydraulic pipes 19b, 15 for the upper gripper jacks 7b.
It branches into b. The first hydraulic pipes 19a and 15b
A first on-off switching valve 10a and a second on-off switching valve IDb that independently open and close the and second hydraulic pipes 19b and 15b are provided, respectively. In the first hydraulic piping 15a and 19a between the first on-off switching valve 10a and the lower gripper jack 7a, a selection switching valve 8a for selecting the gripper jack to be used and the pressure on the lot side of the gripper jacks 7a and 76 are set as pilot pressure. A first pilot check valve 9th is provided. A second hydraulic pipe 15b between the second on-off switching valve 10b and the upper gripper jack 7b
and 19b, a selection switching valve 8b for selecting the gripper jack to be used, and gripper jacks 7a, 7b.
(A second pilot check valve 9b is provided which uses the pressure on the D lot side as a pilot pressure. In the figure, the same reference numerals as in FIG. 3 indicate the same parts.

The hydraulic system for the clipper jack of the present invention in this embodiment has the above-mentioned configuration, and its operation will be explained below. Before that, the forward motion of the tunnel excavator will be explained. First, the gripper jacks 7a, 7b are extended to press the gripper (Sa, 6b) against the shaft wall 6.

In this state, the self-propelled jack 2a.

When the grippers 2b are extended, the grippers 5a and 6b are fixed to the mine wall 3, so the main body 1 moves forward by taking the reaction force.Next, the gripper jacks 7a and 7b are retracted to guide the gripper support 5. When the self-propelled jacks 21L and 2b are retracted while being guided to 1a, the gripper support 5 is drawn forward.Next, the balancing of the load in the circumferential direction of the gripper jack portion will be explained.

The gripper support 5 has a large number of grippers 6a, 6b,
Gripper jacks 7a and 7b are arranged to center the gripper support 5 in any vertical and horizontal positions, and support it while rationally adjusting the curvature of the shaft wall 6 and the grounding state of the grippers 6a and 6b. . Since the weight of the gripper support 5 acts downward, the group 7a of the lower gripper jacks that supports the weight and the group 7b of the upper gripper jacks that do not support the weight are kept in balance by different pressing forces. ing. This will be explained in more detail. Now, let us consider the case where all the gripper jacks 7a and 7b are used. The selection switching valves 8a and 8b are all "open". The first on-off switching valve 10a is set to “open”,
The second on-off switching valve 10b is set to 1CLOSE, and the main switching valve 11 is switched from the neutral boat to the A boat. Then, the pressure oil from the hydraulic pump P flows through the hydraulic pipe 18. First hydraulic piping 19a.

First on-off switching valve 10a, first pilot check valve 9
a, the first hydraulic piping 15a2 is supplied to the bottom side of the lower gripper jack 7a via the selection switching valve 8a, and the piston rods of the six lower gripper jacks 7a extend.

At this time, since the three lower gripper jacks 7a are connected through the first hydraulic pipes 15a and 19a,
The pressing forces of the three lower gripper jacks 7a are evenly distributed.

Next, the first on-off switching valve 10a is set to "closed", the second on-off switching valve 10b is set to "open", and the main switching valve 11 is set to the A boat.

Then, the pressure oil from the hydraulic pump P flows through the hydraulic pipe 18. The second hydraulic piping 19b and the first switching valve 10b.

First pilot check valve 9b, first hydraulic piping 15b
.

It is supplied to the bottom side of the upper gripper jack 7b through the selection switching valve 8b, and the three upper gripper jacks 7b
The piston rod extends. At this time, the six upper gripper jacks 7b are connected to the second hydraulic pipe 15b.

19b, the pressing forces of the six upper gripper jacks 7b are distributed in nine equal parts.

By extending the above-mentioned upper gripper jack 7b and pressing the gripper 6a against the shaft wall 3, a pressing force is generated on the lower gripper jack 7a as a reaction force. At this time, since the first hydraulic pipes 15& on the bottom side of the lower gripper jacks 7a are all connected, the hydraulic pressures of the lower gripper jacks 7a are all equal, and therefore the pressing forces of the lower gripper jacks 78 are all equal. , are equally distributed to the shaft wall 6. It is assumed that the contact surface (the mating shaft wall 3) of any of the six lower gripper jacks 7a is creep-displaced (sinking down), and the jack stroke changes accordingly (elongates). Even at that time, oil moves between the lower gripper jacks 7a, but the gripper pressing force does not change, and the balance of the gripper pressing forces does not change. Then, the position of the gripper support 5 moves downward by the amount that the stroke of the lower gripper jack 7a changes (elongates), and the stroke of the upper gripper jack 7b changes (elongates).

In this way, the gripper pressing force is reduced by a large number of jacks 7a.
, 7b, and the pressing force can be equally distributed, and the balance of the gripping force can be maintained perfectly against the creep displacement and depression of the contact surface, which is a characteristic of soft rock. Furthermore, the problem of the gripper support 5 falling under its own weight is caused by the use of a large number of spool type selection valves 8, 10 that have a lot of internal leakage, so it can be completely solved by using pilot check valves 9a, 9b. It can be solved.

FIG. 7 is a hydraulic circuit diagram showing another embodiment of the hydraulic system for the gripper jack in the tunnel excavator of the present invention.

In this embodiment, pilot check valve selection switching valves 16a and 16b are used in place of the spool valve selection switching valves 8a and 8b in the above-described embodiment. Hydraulic piping for opening/closing operation from hydraulic pump P'
A relief valve 31 is provided in the middle of 52, and this relief valve 6
1 is a pilot check valve selection switching valve 161L.

16b is connected to the pilot operated valve 17 which performs the disconnection/disconnection operation, and the pilot check valve selection switching valves i6a and i6b are connected to the pilot operated valve 17.
It is connected by The operation will be explained. The pressure oil from the hydraulic pump P is appropriately reduced in pressure by the relief valve 31. When the pilot operation valve 17 is opened or closed, the reduced pressure oil is used as pilot pressure to select the pilot check valves 16a and 16.
It is used for "opening" and "closing" of b. This embodiment is more effective in preventing the gripper support 5 from falling by itself than the above-mentioned embodiments.

As is clear from the above examples, since the pressing force of the grits (the hydraulic system for jacks is made up of a plurality of grits) jacks in the tunnel excavation machine of the present invention is distributed in five equal parts, the load balance state is the same as at the beginning. can be maintained. Therefore, unevenness of the wall surface, increase in temporal displacement of the wall surface (ground plane creep or depression) 7 Local displacement of the wall surface, vibration or positional movement of the tunnel excavation machine body or gripper ring, etc., may cause collapse of the gripper ground plane. Since the main cause has been eliminated, the gripper can now be used on a wide range of geology, especially from soft to hard rocks.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view of a general tunnel excavation machine, Fig. 2 is a sectional view taken along line II-II in Fig. 1, Fig. 3 is a hydraulic circuit diagram of the hydraulic system of the clipper jack in a conventional tunnel excavation machine, and Fig. 4 5 is a longitudinal sectional view of a tunnel excavator equipped with a gripper jack hydraulic system of the present invention, and a sectional view taken along the line V-V in FIG. 4, and FIG. 6 is an embodiment of the gripper jack hydraulic system of the present invention. The hydraulic circuit diagram shown in FIG. 7 is a hydraulic circuit diagram showing another embodiment of the hydraulic system for the gripper jack in the tunnel excavation machine of the present invention. DESCRIPTION OF SYMBOLS 1... Tunnel excavator main body, '2a, 2b... Self-propelled jack, 6... Pit wall, 5... Gripper support, 6
1L, <Sb...Gripper, 7a, 7b...Gripper jack, 8IL, 8b...Selection switching valve, 9a, 9
b... Pilot check valve, 10a... First on-off switching valve, 10b... Second on-off switching valve, 11... Main switching valve, 14... Contraction side hydraulic piping, 15a, 19a
...First hydraulic pipe, 15b, 1 pipe b...Second
Hydraulic piping, 16a, 16b...Pilot check valve (selective switching valve). Patent Applicant Hitachi Construction Machinery Co., Ltd. Agent Patent Attorney Tadashi Akimoto Figure 1 Figure 2 Figure 3 Figure 4 i a j Figure 5

Claims (1)

[Scope of Claims] 1. A self-propelled jack is interposed between the main body of the tunnel excavation machine and the gripper support, and a plurality of clipper jacks are installed on the gripper support so that the expansion and contraction direction of the gripper jacks and the radial direction of the tunnel match. In a tunnel excavating machine, the plurality of gripper jacks are each equipped with a gripper, a first group supporting the weight of the gripper support and a second group not supporting the weight of the gripper support. The hydraulic circuit connecting the hydraulic source and the gripper jack is divided into a first hydraulic circuit for the first group and a second hydraulic circuit for the second group, and the first hydraulic circuit and the second hydraulic circuit are divided into two hydraulic circuits. A first on-off switching valve and a second on-off switching valve that independently open and close the valves are provided, respectively, and a gripper jack is selected to be used between the first on-off switching valve and the second on-off switching valve and the plurality of gripper jacks. A hydraulic system for grits and jacks in a tunnel excavator, characterized in that all selective switching valves are installed. 2. Claim 1, characterized in that there is a pilot check valve between the first on-off switching valve, the second on-off switching valve, and the selection switching valve, which uses the pressure on the rond side of the gripper jack as a pilot pressure. Hydraulic system for grit jacking in a tunnel excavation machine as described in Section.