JP7030554B2 - Seal structure and method of shield excavator with center folding mechanism - Google Patents

Description

The present invention relates to a shield excavator having a center-folding mechanism, and more particularly to a sealing structure and method for the center-folding portion.

As a shield excavator for tunnel construction, as shown in Patent Document 1, there is a break-action type that allows a curved tunnel to be constructed by changing the excavation direction.
In this method, the main body of the shield excavator is divided into a front body and a rear body, and the front body and the rear body are connected so as to be bendable by a center folding mechanism.

The center folding mechanism is provided in the gap between the wrap portion and the wrap portion, which wraps the rear end portion of the front fuselage and the front end portion of the rear fuselage with the front end portion of the rear fuselage inside, and seals this gap. Includes a regular seal and a plurality of connecting jacks arranged at predetermined intervals in the circumferential direction of the front torso and the rear torso, each of which connects the front torso and the rear torso in an axially stretchable manner.
Here, by expanding and contracting the plurality of connecting jacks, more specifically, by contracting the connecting jack on the bending side and extending the connecting jack on the opposite side among the plurality of connecting jacks, it is possible to realize a middle fold between the front torso and the rear torso. It is configured to do.

Japanese Unexamined Patent Publication No. 11-6390

However, the seal portion of the shield excavator with a bending mechanism for curved tunnels may deteriorate or break during excavation in the ground. If the seal is deteriorated or damaged, water in the ground will flow into the machine (inside the shield excavator), which may lead to a serious accident. Therefore, there is a demand for a device that can urgently block the inflow of groundwater when an abnormality occurs in the seal portion.

In view of such an actual situation, it is an object of the present invention to provide a safer sealing structure (and method) for a shield excavator having a bending mechanism.

The shield excavator according to the present invention has a front body having a cutter head on the front end side, a rear body connected to the rear end of the front body, and a bendable connection between the front body and the rear body. It is equipped with a folding mechanism.
The center folding mechanism includes a wrap portion formed by wrapping the rear end portion of the front body and the front end portion of the rear body, a regular seal provided in a gap between the wrap portions and sealing the gap, and the above-mentioned. The plurality of connecting jacks, which are arranged at predetermined intervals in the circumferential direction of the front body and the rear body, each of which connects the front body and the rear body so as to be expandable and contractible in the axial direction. By expanding and contracting the jack, the front body and the rear body are configured to be bent in the middle.
The center folding mechanism is further provided at either the rear end portion of the front cylinder or the front end portion of the rear cylinder, and when all of the plurality of connecting jacks are contracted to a predetermined position , the front cylinder is further provided. It is possible to seal the gap of the lap portion by contacting the other of the rear end portion and the front end portion of the rear fuselage, and when not all of them are shrunk to a predetermined position, the rear end portion of the front fuselage and the front end of the rear fuselage. Includes an emergency seal that does not touch the other side of the part .
The emergency seal is preferably arranged on the inside of the machine (inside the shield excavator) side of the regular seal in the gap of the lap portion.

The present invention also relates to either the rear end portion of the front body or the front end portion of the rear body by contracting all of the plurality of connecting jacks in a shield excavator having a center bending mechanism when the normal seal is abnormal. Provided is an emergency sealing method for a shield excavator, in which an emergency seal provided on one side is brought into contact with the other side to seal a gap in the lap portion.

According to the present invention, even if the regular seal is deteriorated or damaged, the emergency seal functions by the operation of shrinking all the connecting jacks to maintain the watertightness of the middle fold (watertightness of the middle fold). Or you can recover.
In addition, since the water blocking function of the middle fold can be restored by the operation of shrinking all the connecting jacks, for example, even if groundwater flows into the machine and the power is lost, the jacks are unloaded (hydraulic jacks). In that case, just by removing the load by removing the hydraulic pressure), the jack shrinks due to the soil water pressure applied to the front body, the emergency seal functions, and the water stop function can be restored.

In addition, by arranging the emergency seal inside the machine rather than the regular seal, it can be placed in a clean environment while the regular seal is functioning, deterioration and the like can be suppressed, and it is possible to prepare for an emergency.

Sectional drawing of the shield excavator in tunnel construction which shows one Embodiment of this invention. Layout diagram of the connecting jack corresponding to the arrow view of AA in FIG. Detailed view of part B (wrap part between front torso and rear torso) in FIG. Explanatory drawing of emergency water stop operation when the regular seal is damaged Explanatory drawing of the filler injection apparatus shown as another embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a cross-sectional view of a shield excavator during construction of a shield tunnel showing an embodiment of the present invention.

In the shield excavator 1 of the present embodiment, in order to be able to excavate a curved tunnel, a cylindrical main body is divided into a front body 2 and a rear body 3, and the front body 2 and the rear body 3 are bent in the middle. It is connected via 4.

The front body 2 is provided with a cutter head 5 on the front end side (face side) thereof, and a partition wall (bulk head) 6 is provided on the rear side of the cutter head 5.

The cutter head 5 has a disk shape having a slightly larger diameter than the outer peripheral surface (skin plate outer peripheral surface) of the front cylinder 2 (and the rear cylinder 3), and has a large number of cutter bits 5a on the front surface. The cutter head 5 is connected to the swivel ring 8 via a support arm 7. The swivel ring 8 is rotatably supported by the bulkhead 6 while penetrating the bulkhead 6. Then, behind the partition wall 6, the ring gear 9 integrally attached to the swivel ring 8 is meshed with the pinion gear 11 attached to the output shafts of the motors 10 arranged in the circumferential direction. Therefore, the cutter head 5 turns with the motor 10 as a drive source and excavates the ground.

In the figure, 101 shows a tunnel wall surface (wall surface of the ground) excavated by the cutter head 5. The outer diameter of the front body 2 (and the rear body 3) is smaller than the outer diameter of the cutter head 5. Therefore, there is a gap 102 between the tunnel wall surface (wall surface of the ground) 101 excavated by the cutter head 5 and the outer peripheral surface of the front body 2 (and the rear body 3).

The partition wall 6 is also provided with a rotary joint 12 for connecting the device on the side of the cutter head 5 and the device behind the partition wall 6 by hydraulic pressure or electric wires.

A chamber 13 is partitioned between the cutter head 5 and the partition wall 6. Due to the excavation of the ground by the cutter head 5, the excavated earth and sand accumulate in the chamber 13 and generate earth pressure. The earth discharge mechanism 14 discharges the excavated earth and sand in the chamber 13 to the rear of the partition wall 6, and at the same time controls the earth pressure in the chamber 13 to prevent the face from collapsing.

The rear fuselage 3 is provided with an elector 15 for assembling and lining the segment SG inside the rear fuselage 3.
The erector 15 has a grip portion 15a that grips the segment SG via a gripping hardware KM attached to the segment SG, and while gripping the segment SG, the segment SG is moved in the tunnel axial direction, the radial direction, and the circumferential direction. Set in place. In this way, a plurality of segment SGs are assembled in the circumferential direction to form a segment ring, which is connected to the formed segment ring to construct a cylindrical lining body.

The rear fuselage 3 also includes a hydraulic propulsion jack 16 as a propulsion mechanism for advancing the main body of the shield excavator 1 together with excavation.
A plurality of propulsion jacks 16 are arranged on the inner peripheral surface of the rear body 3 at substantially equal intervals in the circumferential direction, and thrust is generated by pushing the end faces of the lining segment SG.
When the propulsion jack 16 is extended and excavated for one ring, the jack is returned and lining for one ring. Therefore, excavation and lining are repeated for each ring.

The rear fuselage 3 is also provided with a tail seal 17 on the inner peripheral surface of the rear end portion.
Since the segment SG is assembled in the rear cylinder 3, the outer diameter of the lining segment SG is smaller than the inner diameter of the rear cylinder 3. Therefore, a gap is formed between the inner peripheral surface of the rear end portion of the rear body 3 and the lining segment SG. Therefore, the tail seal 17 is provided so that groundwater and earth and sand do not enter the machine (inside the shield excavator 1) through this gap.
The tail seal 17 is attached to the inner peripheral surface of the rear end portion of the rear body 3 in two front and rear stages over the entire circumference, and is in sliding contact with the outer peripheral portion of the lining segment SG to close the gap.

Specifically, as the tail seal 17, a metal brush (wire brush) or a urecon seal in which urethane foam is sprayed on the wire brush is used. Further, grease is filled between the first-stage tail seal and the second-stage tail seal. Therefore, a grease supply pipe (not shown) from the grease supply pump is provided in the wall portion of the skin plate, and the discharge port thereof is opened between the tail seals.

The gap 103 between the tunnel wall surface (wall surface of the ground) excavated by the cutter head 5 and the lining segment SG is larger than the gap 102. The gap 103 is filled with the backfill injection material at an appropriate timing.

Next, the center bending mechanism 4 that connects the front body 2 and the rear body 3 so as to be bendable will be described with reference to FIGS. 1 to 3. 2 is a view taken along the arrow AA of FIG. 1, and FIG. 3 is a detailed view of a portion B of FIG.

The center folding mechanism 4 is a regular seal provided in the gap between the wrap portion 40 formed by wrapping the rear end portion of the front cylinder 2 and the front end portion of the rear cylinder 3 and the wrap portion 40 between the front cylinder 2 and the rear cylinder 3. 42 (FIG. 3) and a hydraulic connecting jack 43 for connecting the front body 2 and the rear body 3 at the front and rear of the lap portion 40 are included.

The wrap portion 40 is wrapped with the rear end of the front body 2 on the outside and the front end of the rear body 3 on the inside. The reason why the rear end portion of the front cylinder 2 is on the outside and the front end portion of the rear cylinder 3 is on the inside is to prevent earth and sand from entering the gap of the lap portion 40 during digging.
Further, in order to enable smooth bending while maintaining the lap state, the outer peripheral surface of the front end portion of the inner rear body 3 is a spherical surface 41 centered on a point O on the central axis of the front body 2 and the rear body 3. There is. The outer peripheral surface of the rear end portion of the outer front body 2 may be a substantially straight cylindrical surface, but may be a concave spherical surface corresponding to the spherical surface (convex spherical surface) 41.

The regular seal 42 is attached to the inner peripheral surface of the rear end portion of the outer front cylinder 2 in two front and rear stages over the entire circumference, and is slidably contacted with the spherical surface 41 on the outer rear cylinder 3 side to seal the gap of the wrap portion 40 in a watertight manner. do.
Therefore, the gap of the lap portion 40 is separated from the inside of the machine (inside the shield excavator) side and the outside of the machine (outside the shield excavator) side with the regular seal 42 as a boundary. When the rear end of the front body 2 is placed on the outside and the front end of the rear body 3 is placed on the inside, the front side of the regular seal 42 is the inside of the machine and the rear side is the outside of the machine.

As the regular seal 42, specifically, a seal made of rubber or urethane and having a ring-shaped chevron cross section or a convex cross section is used. Also, a lip seal (see FIG. 3) is preferably used. The lip seal is composed of a base portion and a lip portion, and the water pressure applied to the depression between the base portion and the lip portion can enhance the water stopping property.

Further, grease is filled between the first-stage seal and the second-stage seal. Therefore, a grease supply pipe (not shown) from the grease supply pump is provided in the wall portion of the rear end portion of the front body 2, and the discharge port thereof is opened between the seals.

A plurality of connecting jacks 43 are arranged at predetermined intervals in the circumferential direction of the front body 2 and the rear body 3, and the front body 2 and the rear body 3 are connected to each other so as to be expandable and contractible in the axial direction. The number is theoretically required to be 4 or more, and is actually determined from the required thrust. In FIG. 2, the number is eight.

When the shield excavator 1 goes straight, all the connecting jacks 43 are controlled to the neutral position (the intermediate position between the most extended position and the shortest position).
When the shield excavator 1 is bending, the connecting jack on the bending side is retracted from the neutral position, and the connecting jack on the opposite side is extended from the neutral position. Achieve a middle fold.

For example, when turning to the left in the traveling direction (back side of the paper) in FIG. 2, the connecting jack 43c on the left side of FIG. 2 is contracted and the connecting jack 43g on the right side is extended. At this time, the upper and lower connecting jacks 43a and 43e are maintained in the neutral position. The upper left and lower left connecting jacks 43b and 43d are less than the shortened amount of the left connecting jack 43c, and conversely, the upper right and lower right connecting jacks 43h and 43f are less than the extension amount of the right connecting jack 43g. Amount, stretch.

Such control is performed by the hydraulic control device (not shown) of the connecting jack 43 according to the digging direction instructed by the predetermined digging program or in accordance with the digging direction directly instructed by the worker. It is automatically performed by calculating the expansion / contraction amount of 43a to 43h).

The center folding mechanism 4 of the present embodiment is further configured to include an emergency seal 44 in order to cope with deterioration and breakage of the normal seal 42.

As shown in FIG. 3, the emergency seal 44 is attached to the inner peripheral surface of the rear end portion of the front fuselage 2 in front of the regular seal 42, that is, at a position inside the machine from the regular seal 42 over the entire circumference.

The emergency seal 44 does not come into contact with the inner peripheral surface of the front end portion of the rear cylinder 3 within the range in which the front cylinder 2 and the rear cylinder 3 bend during normal straight movement or bending of the shield excavator 1.
On the other hand, in the emergency seal 44, when all of the plurality of connecting jacks 43 are contracted (that is, the front torso 2 and the rear torso 3 become straight, and the front torso 2 retracts to the rear torso 3). (When the lap length becomes longer), as shown in FIG. 4, it comes into contact with the inner peripheral surface of the front end portion of the rear body 3 which is the other party, and closes the gap of the lap portion 40.

As the emergency seal 44, specifically, a ring-shaped seal member made of rubber or urethane and having a circular cross section or a chevron cross section is used.

Next, a case where the regular seal 42 is deteriorated or damaged will be described.
If the regular seal 42 is damaged, groundwater may flow into the machine from the outside of the front body 2 and the rear body 3 (outside the machine) through the gap of the wrap portion 40.

In this case, as an emergency response of the worker, or as a result of detecting the inflow of water or the like with an appropriate sensor, the hydraulic control device is used to shrink all the connecting jacks 43.
However, in the hydraulic control device, it is prohibited (interlocked) by software to shrink all the connecting jacks 43 so that the regular seal 42 does not deviate from the seal position. Therefore, it is necessary to program so that the interlock can be released at the time of emergency response.

By the action of contracting all the connecting jacks 43, the front torso 2 and the rear torso 3 become straight, and the front torso 2 retracts to lengthen the lap length with the rear torso 3. As a result, as shown in FIG. 4, the emergency seal 44 on the front body 2 side comes into contact with the front end portion of the rear body 3 to seal the gap of the wrap portion 40. As a result, the emergency seal 44 can be made to function to restore the water blocking function (watertightness of the center-folded portion).

In addition, if the regular seal 42 is damaged, it is possible that the power supply will be lost due to the inflow of water into the machine. If the power supply is lost, it becomes difficult to control the connecting jack 43 by the hydraulic control device.

However, even when the power supply is lost, it is relatively easy to remove the hydraulic pressure from the connecting jack 43 by removing the hydraulic hose of the connecting jack 43 or the like. Further, while the front body 2 is subjected to a force pushing backward by the soil water pressure acting from the front end surface side thereof, the rear body 3 is held by the segment SG under construction via the propulsion jack 16. .. Therefore, by removing the hydraulic pressure of the connecting jack 43, the front body 2 retracts due to the soil water pressure, the connecting jack 43 can be contracted, and the emergency seal 44 can function. Therefore, even in such a case, the water blocking function can be restored.

According to the present embodiment, by providing the emergency seal 44 that functions when all of the plurality of connecting jacks 43 are contracted, it is possible to take emergency water stop measures in the event of an abnormality in the regular seal 42.
Further, since the connecting jack 43 that connects the front cylinder 2 and the rear cylinder 3 so as to be bendable is used, it is not necessary to newly install a jack for emergency water stoppage, and the cost increase can be suppressed.

Further, according to the present embodiment, the emergency seal 44 is arranged inside the machine from the regular seal 42 in the gap of the wrap portion 40, so that the emergency seal 42 is kept in a clean environment while the regular seal 42 is functioning. It can be placed, its deterioration can be suppressed, and it can be prepared for emergencies.

The emergency seal 44 may be provided not at the rear end of the front body 2 but at the front end of the rear body 3, and in any case, when all of the plurality of connecting jacks 43 are contracted, the emergency seal 44 may be provided to the other party. It suffices if it is possible to abut and seal the gap of the wrap portion 40.

Next, another embodiment of the present invention will be described with reference to FIG.
The embodiment of FIG. 5 is provided with a filler injection device in addition to the embodiment of FIG.

The center folding mechanism 4 of the present embodiment is further configured to include a filler injection device 45 capable of injecting a water-curable filler into the gap of the wrap portion 40 from the inside of the machine.

The filler injection device 45 penetrates the inside and outside of the rear cylinder 3 (the cylinder arranged inside in the wrap portion) inside the wrap portion 40 and opens to the outside of the machine behind the regular seal 42. It includes a 45a and a valve 45b that can open and close the injection passage 45a.

In the present embodiment, when the regular seal 42 is damaged, all the connecting jacks 43 are shrunk to make the emergency seal 44 function, and then the normally closed valve 45b of the filler injection device 45 is opened inside the machine. , The underwater-curable filler is supplied from the inside of the machine to the outside of the machine through the injection passage 45a. The filler supplied to the outside of the machine rides on the flow of water that tries to enter the gap of the wrap portion 40 by the water pressure outside the machine, and is injected into the gap of the wrap portion 40, especially the part of the damaged regular seal 42. .. As a result, the portion of the regular seal 42 damaged by the filler can be closed. Therefore, in combination with the emergency seal 44, it becomes a more reliable emergency water stop measure and the safety can be enhanced.

In addition, the illustrated embodiment is merely an example of the present invention, and the present invention includes various improvements and improvements made by those skilled in the art within the scope of the claims, in addition to those directly shown by the described embodiments. It goes without saying that it involves changes.

For example, in the illustrated embodiment, the wrap portion 40 is wrapped with the rear end portion of the front body 2 on the outside and the front end portion of the rear body 3 on the inside, but conversely, the rear end portion of the front body 2 is wrapped. It is also possible to wrap the inner side and the front end portion of the rear body 3 on the outer side. In the case of reverse lap, the rear side of the regular seal is the inside of the machine and the front side is the outside of the machine. Therefore, the emergency seal will be placed inside the machine behind the regular seal. In addition, the injection passage of the filler injection device shall be opened to the outside of the machine in front of the regular seal by penetrating the inside and outside of the front body (the body arranged inside in the wrap part) inside the wrap part. Become.

1 Shield excavator
2 Front torso 3 Rear torso 4 Center folding mechanism 5 Cutter head 5a Cutter bit 6 Bulkhead
7 Support arm 8 Swing ring 9 Ring gear 10 Motor 11 Pinion gear 12 Rotary joint 13 Chamber 14 Soil removal mechanism 15 Electa 16 Propulsion jack 17 Tail seal 40 Wrap part 41 Spherical surface 42 Regular seal (lip seal)
43 (43a-43h) Connecting jack 44 Emergency seal 45 Filler injection device 45a Injection passage 45b Valve 101 Tunnel wall surface (ground wall surface)
102, 103 gap

Claims (7)

A front fuselage with a cutter head on the front end side,
The rear torso connected to the rear end of the front torso,
A center folding mechanism that connects the front body and the rear body so as to be bendable,
It is a shield excavator equipped with
The center folding mechanism is
A wrap portion formed by wrapping the rear end portion of the front torso and the front end portion of the rear torso, and a wrap portion.
A regular seal provided in the gap of the wrap portion and sealing this gap,
Includes a plurality of connecting jacks arranged at predetermined intervals in the circumferential direction of the front torso and the rear torso, each of which connects the front torso and the rear torso in an axially stretchable manner.
By expanding and contracting the plurality of connecting jacks, the front body and the rear body are configured to be bent in the middle.
The center folding mechanism is further provided at either the rear end portion of the front cylinder or the front end portion of the rear cylinder, and when all of the plurality of connecting jacks are contracted to a predetermined position , the front cylinder is further provided. It is possible to seal the gap of the lap portion by contacting the other of the rear end portion and the front end portion of the rear fuselage, and when not all of them are shrunk to a predetermined position, the rear end portion of the front fuselage and the front end of the rear fuselage. A shield excavator characterized by containing an emergency seal that does not abut on the other side of the part . A front fuselage with a cutter head on the front end side,
The rear torso connected to the rear end of the front torso,
A center folding mechanism that connects the front body and the rear body so as to be bendable,
It is a shield excavator equipped with
The center folding mechanism is
A wrap portion formed by wrapping the rear end portion of the front torso and the front end portion of the rear torso, and a wrap portion.
A regular seal provided in the gap of the wrap portion and sealing this gap,
Includes a plurality of connecting jacks arranged at predetermined intervals in the circumferential direction of the front torso and the rear torso, each of which connects the front torso and the rear torso in an axially stretchable manner.
By expanding and contracting the plurality of connecting jacks, the front body and the rear body are configured to be bent in the middle.
The center folding mechanism is further provided at either the rear end portion of the front fuselage or the front end portion of the rear fuselage so as to be separated from the other, and all of the plurality of connecting jacks are brought to a predetermined position. A shield excavator comprising an emergency seal capable of abutting the other of the rear end of the front body and the front end of the rear body when contracted to seal the gap in the wrap. The first or second aspect of the present invention, wherein the wrap portion is formed by wrapping the rear end portion of the front body and the front end portion of the rear body with the front end portion of the rear body inside. Shield excavator. The shield excavator according to any one of claims 1 to 3 , wherein the emergency seal is arranged inside the machine in a gap of the wrap portion. The shield according to any one of claims 1 to 4, wherein the center folding mechanism further includes a filler injection device capable of injecting a filler from the inside of the machine into the gap of the lap portion. Digger. The filler injection device penetrates the inside and outside of the rear end of the front body and the front end of the rear body constituting the wrap portion, whichever is arranged inside in the wrap portion. The shield excavator according to claim 5, further comprising an injection passage provided and a valve that can open and close the injection passage. A front fuselage with a cutter head on the front end side,
The rear torso connected to the rear end of the front torso,
A center folding mechanism that connects the front body and the rear body so as to be bendable,
Equipped with
The center folding mechanism is provided in a gap between a wrap portion formed by wrapping the rear end portion of the front body and the front end portion of the rear body, and a gap between the wrap portions, and a regular seal for sealing the gap. A plurality of connecting jacks arranged at predetermined intervals in the circumferential direction of the front torso and the rear torso, each of which connects the front torso and the rear torso so as to be expandable and contractible in the axial direction. The expansion and contraction of the jack is configured to realize a middle fold between the front torso and the rear torso.
In the shield excavator
In the event of an abnormality in the regular seal, by shrinking all of the plurality of connecting jacks, the emergency seal provided on either the rear end portion of the front fuselage or the front end portion of the rear fuselage is brought into contact with the other party. An emergency sealing method for a shield excavator, which comprises sealing the gap of the lap portion.

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