JP4489620B2 - Shield machine - Google Patents

Description

  The present invention relates to a shield machine, and more particularly to an improvement of the cutter bit replacement structure in a shield machine in which a cutter bit can be easily replaced.

  Conventionally, in order to form a tunnel such as a tunnel, a shield machine that moves forward while excavating the ground is known.

  This shield machine has a substantially cylindrical shape as a whole, and a plurality of cutter spokes extending radially are arranged on a face plate (front end face) facing the ground to be excavated among both end faces, A number of cutter bits installed on the outer surface of the cutter spoke are installed. While pressing the cutter spoke against the excavated surface (face) of the ground (advancing the shield machine), By rotating around the cylindrical axis by power and rotating the cutter spoke, the surface to be excavated is scraped little by little, and the rock and earth and sand generated by this scraping are removed from the gap between the cutter spokes to the outside. It is comprised so that it may discharge to (behind the face plate).

  By the way, the cutter bit provided in such a shield machine is worn out by use, and the excavation performance deteriorates depending on the worn out cutter bit. It is desirable to exchange bits.

  However, since the cutter bit is arranged on the front end surface in the traveling direction of the shield machine, when the cutter bit on the front end surface in the traveling direction is to be replaced, the shield machine is once retracted to the wellhead and the entire excavator is excavated. For example, it is formed in advance so that a shaft from the ground surface intersects the planned excavation area planned to be formed in the future by excavating from the tunnel or by the shield excavator excavating in the future. Replace the cutter bit fixed to the cutter spoke with the cutter bit carried into the excavation tunnel through the shaft while the machine entered and the front-end cutter spoke was exposed. A method of taking the bit out of the ground through a shaft is adopted.

  However, forming a shaft for exchanging cutter bits is disadvantageous in terms of cost, and for the reason that a building such as a house already exists in the corresponding part on the ground, it is necessary to form a shaft. There are also individual circumstances where sufficient space cannot be secured.

  Further, if the shield machine is extracted from the tunnel every time the cutter bit is replaced, there is a lot of waste such as time for reciprocating the tunnel, which may cause a delay in the construction period.

  In view of this, a technique has been proposed in which the cutter bit can be easily replaced without providing another different mine shaft or reciprocating the shield machine to the pit.

  That is, for example, by connecting the cutter bits in a row with a chain member and accommodating them in the cutter spoke, the bit connected to the chain can be drawn into the rotation center chamber together with the chain. In the chamber, a technique is known in which a bit is removed from the chain and the bit is exchanged, and then the chain is pushed out of the chamber to return to a state where excavation with a new bit is possible.

A technique for displacing the bit in the radial direction of the front end of the shield machine for the purpose of equalizing the wear of the bit is also known. (Patent Document 1).
JP 2004-27523 A

  However, in the above-described various conventional shield machines, the equipment for exchanging the bits becomes large, and the manufacturing cost of the shield machine increases, and the bits under a narrow environment with concern about collapse of natural ground. Must be replaced.

  Therefore, it cannot be said that the exchange is easy, and there is a problem that it takes time to exchange the bits.

  On the other hand, when replacing the bit after injecting the ground conditioner into the ground and performing ground improvement, although safety can be sufficiently ensured, there is a concern that the construction cost will increase or the construction period will be extended.

  This invention is made in view of the said situation, Comprising: It aims at providing the shield machine which can change a cutter bit safely and easily, and can shorten the exchange time of a bit. .

  The shield machine according to the present invention divides a cutter spoke into a plurality of pieces in the radial direction (longitudinal direction), each of which is divided into short divided cutter spokes, and these divided cutter spokes are formed in the center portion of the front end face. The cutter bit of each divided cutter spoke is exchanged by taking it into the storage chamber.

That is, the shield machine according to claim 1 of the present invention has a substantially cylindrical shape as a whole, and a plurality of radially extending cutter spokes are disposed on the front end surface of the both end surfaces facing the object to be excavated. The front end surface rotates about the axis of the cylindrical shape, and a plurality of cutter bits are installed on the outer surface of the cutter spoke. The rotation of the cutter spoke accompanying the rotation of the front end surface, and the excavation In the shield machine that forms a tunnel-like tunnel in the excavation target by proceeding toward the target, the cutter spoke is divided into a plurality of portions having a predetermined length in the longitudinal direction and slides in the longitudinal direction, respectively. capable disposed, of said front end face, the heart portion in including an axis of the cylindrical shape, each of the divided cutter spokes obtained by dividing the predetermined length, the outer Split spoke accommodating chamber for accommodating and isolated are formed from the length along the axial direction of the split spoke accommodating chamber, than the total width of the width along the axial direction of at least all of the divided cutter spokes It is formed so as to be long and accommodates a plurality of the divided cutter spokes arranged in the width direction at the same time .

  According to the shield machine according to claim 1 of the present invention configured as described above, the cutter spoke is divided into a plurality of portions having a predetermined length in the longitudinal direction. Each of the obtained divided cutter spokes has a length shorter than the entire length of the cutter spoke.

  On the other hand, since the divided spoke accommodation chambers for accommodating the divided cutter spokes are formed at the center of the front end surface, the divided cutter spokes can be slid in the longitudinal direction and accommodated in the divided spoke accommodation chambers. .

  Moreover, since the divided spoke accommodation chambers in which the divided cutter spokes are accommodated are isolated from the outside, the cutter bits of the divided cutter spokes can be exchanged safely and easily in the divided spoke accommodation chamber. .

  And after exchanging the cutter bit, by using a known means, by sending out each divided cutter spoke to the outside of the divided spoke storage chamber and returning it to the original position, with the cutter spoke of the original length before the division, That is, excavation and excavation can be performed as a conventional cutter spoke.

  Further, the storage chamber for storing the cutter spoke and exchanging the cutter bit may have a small diameter enough to secure a height (diameter) for storing the divided cutter spoke shorter than the entire length of the cutter spoke. Therefore, the surface facing the object to be excavated, that is, the fishtail, is made as small as possible in the center of the front end surface, and the length of the cutter spoke that performs substantial excavation can be sufficiently secured as before, and the excavation efficiency is reduced. There is no invitation.

  Furthermore, even if the divided spoke accommodation chamber is made larger than the divided cutter spoke to be accommodated, the excavation efficiency is not greatly impaired, while a working space for exchanging the cutter bit in the accommodation chamber is not provided. It is possible to ensure a wide range and improve the exchange workability.

  The number of cutter spokes may be any number as long as it is a plurality of 2 or more, but practically, it is divided into two parts, an inner peripheral part and an outer peripheral part on the front end face. If it does, the effect mentioned above can fully be exhibited.

Further, it is most preferable to divide all the divided cutter spokes so as to have the same length because the radius of the storage chamber can be effectively reduced.
Furthermore, the division | segmentation cutter spoke can be arranged in the width direction inside the division | segmentation spoke accommodation chamber, and can be accommodated compactly.

  The shield machine according to claim 2 of the present invention is the shield machine according to claim 1, wherein the divided cutter spokes slid in the sliding direction are passed to the outside of the divided spoke accommodation chamber on the outer peripheral surface of the divided spoke accommodation chamber. And a water stop gate that is displaced between a closed position that covers the opening in a water-tight manner and an open position that exposes the opening.

  According to the shield machine according to claim 2 of the present invention configured as described above, when the divided cutter spoke is accommodated in the accommodation chamber and when the divided cutter spoke accommodated in the accommodation chamber is discharged outside the accommodation chamber. The water stop gate is displaced to the open position, and the split cutter spokes are taken into and out of the storage chamber through the opening.On the other hand, when the split cutter spoke is stored in the storage chamber, the water stop gate is displaced to the closed position to open the opening. Covering with water tightness can prevent the external earth and sand and water from unexpectedly flowing into the storage chamber from the opening, thereby ensuring the safety of cutter bit replacement work in the storage chamber. can do.

  In addition, when the water stop gate is in the open position, that is, when the divided cutter spokes are taken into and out of the storage chamber through the opening, external earth and sand and water may flow into the storage chamber through the opening. In the state where is in the closed position, by further comprising a pressurizing means so as to fill the storage chamber in advance with a liquid such as water applied to a pressure against the pressure into which the earth and sand flow into the storage chamber, Even in the state after the water stop gate is moved to the open position, it is possible to prevent or suppress the sediment and water from flowing into the storage chamber.

  The shield machine according to claim 3 of the present invention is the shield machine according to claim 1 or 2, wherein a discharge means for discharging the earth and sand that has flowed into the interior to the inside of the divided spoke housing chamber is provided. It is connected.

  According to the shield machine according to the third aspect of the present invention configured as described above, even when the earth and sand or water from the outside flows into the accommodation chamber through the opening when the divided cutter spokes are taken into and out of the accommodation chamber through the opening. After the water stop gate is moved to the closed position, the earth and sand and water in the storage chamber can be discharged out of the storage chamber by the discharging means, and when exchanging the cutter bit in the storage chamber, the soil and water in the work space can be discharged. Etc. can be prevented and a work space can be ensured.

Shield machine according to claim 4 of the present invention, in the shield machine according to any one of claims 1 or et 3, between the divided cutter spokes adjacent to each other in and out in the radial direction of the front end surface, An uneven shape that engages with the rotation direction about the axis is provided.

According to the shield machine according to claim 4 of the present invention configured as described above, the divided cutter spokes are engaged with each other by the concavo-convex shape on the front end surface, so that the original length before division is integrated. Rotating around the axis as a simple cutter spoke, it is possible to prevent the excavation efficiency due to the cutter spoke from decreasing.

Shield machine according to claim 5 of the present invention, in the shield machine according to any one of claims 1 or et 4, each divided cutter spokes, the predetermined engaged portion is formed, the The divided spoke housing chamber may be an engaged portion (a protruding protrusion (engaged protrusion)) of each divided cutter spoke housed in the divided spoke housing chamber or a recessed cut. It may be a notch-shaped one (engaged notch), and a moving means for sequentially moving each of the divided cutter spokes in the axial direction is provided.

According to the shield machine according to the fifth aspect of the present invention configured as described above, the plurality of divided cutter spokes continuous in the longitudinal direction are sequentially accommodated in the accommodation chamber from the divided cutter spoke on the inner peripheral side on the front end surface. However, after one divided cutter spoke is accommodated in the accommodating chamber, the moving means engages with the engaged portion of the accommodated divided cutter spoke, and this divided cutter spoke is axially moved in the accommodating chamber. Thus, an accommodation space for accommodating the next divided cutter spoke can be secured in the accommodation chamber. And by repeating this accommodation and movement, the divided cutter spokes can be accommodated one by one in the accommodation chamber one by one in the width direction.

  Contrary to the housing of the divided cutter spokes in the housing chamber, when the divided cutter spokes are sent out from the housing chamber, the moving means moves to the engaged portions of the divided cutter spokes housed in the width direction in the housing chamber. By engaging and moving in the axial direction, the divided cutter spokes can be sequentially sent out of the storage chamber one by one.

  According to the shield machine according to the present invention, each divided cutter spoke can be slid in the longitudinal direction and accommodated in the divided spoke accommodation chamber.

  Moreover, since the divided spoke accommodation chambers in which the divided cutter spokes are accommodated are isolated from the outside, the cutter bits of the divided cutter spokes can be exchanged safely and easily in the divided spoke accommodation chamber. .

  And after exchanging the cutter bit, by sending out each divided cutter spoke to the outside of the divided spoke storage chamber and returning it to the original position, it is a cutter spoke of the original length before dividing, that is, as a conventional cutter spoke , Drilling, digging can be performed.

  In addition, the surface of the front end face that faces the object to be excavated, that is, the fishtail, is made as small as possible, and the length of the cutter spoke that performs substantial excavation can be sufficiently secured as before. There is no invitation.

  Furthermore, even if the divided spoke accommodation chamber is made larger than the divided cutter spoke to be accommodated, the excavation efficiency is not greatly impaired, while a working space for exchanging the cutter bit in the accommodation chamber is not provided. It is possible to ensure a wide range and improve the exchange workability.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS The best mode for carrying out a shield machine according to the present invention will be described below with reference to the drawings.

  1 is a schematic view showing a shield machine 1 according to an embodiment of the present invention, FIG. 2 (a) is a front view of the shield machine shown in FIG. 1 as viewed from the front end surface side, and FIG. FIG. 4A is a cross-sectional view schematically showing a cross section taken along line MM in FIG. 5A, and FIG. 4C is a cross-sectional view schematically showing a cross section taken along line NN in FIG. 3 is a diagram showing details of the cutter spoke of the shield machine shown in FIG. 1, FIG. 4 is a diagram schematically illustrating the operation of the shield machine shown in FIG. 1, and FIGS. 5 and 6 are diagrams of the shield machine. It is a figure explaining a detailed effect | action.

  As shown in FIG. 1, the shield machine 1 of the present embodiment has a substantially cylindrical shape as a whole, and a face plate 3 that is a front end surface that faces a ground or the like that is not shown in the drawing, of both end surfaces thereof. The spoke support portions 4 are formed to support the four cutter spokes 8 extending radially from the central portion of the cylindrical shape, and a number of cutter bits 5 are installed on the outer surface of each cutter spoke 8.

  Here, the cutter bit 5 installed in each cutter spoke 8 projects forward from a hole formed in the spoke support portion (spoke attachment portion) 4 in a state where the cutter spoke 8 is supported by the spoke support portion 4. ing.

  When the center shaft 2 that rotates the face board 3 around its axis rotates, the face board 3 and the cutter spoke 8 (cutter bit 5) rotate, and the shield machine 1 itself toward the ground to be excavated. Is advanced, the cutter bit 5 gradually excavates the ground to form a tunnel-like mine shaft in the ground.

  In addition, a substantially conical shape projecting forward Fr from the cutter bit 5 of the cutter spoke 8 so as to lead the excavation direction by the cutter bit 5 at the center side of the face plate 3 and facing the ground. A fishtail 6 is formed, and a fishtail bit 7, which is a drilling blade similar to the cutter bit 5, is installed on the outer surface of the fishtail 6.

  Then, as will be described later, the cutter spoke 8 is divided and accommodated in a portion Rr behind the fish tail 6 (including a portion corresponding to the axial position where the cutter spoke 8 is disposed). A split spoke housing chamber 10 (see the schematic diagram shown in FIG. 2) is formed as an exchange work space for attaching and detaching the cutter bit 5 installed in the cutter spoke 8 to the cutter spoke 8.

  The cutter spoke 8 is divided into two parts (divided cutter spokes) 8a and 8b, each of which is an inner peripheral side part and an outer peripheral side part, each of which is approximately ½ of the entire length in the longitudinal direction. The inner peripheral side divided cutter spoke 8a and the outer peripheral side divided cutter spoke 8b are independently slid along the longitudinal direction (radial direction R; see FIG. 2A). It is allowed.

  Each of the divided cutter spokes 8a and 8b is formed so as to be slightly displaced in the thickness direction thereof, that is, the front and rear directions Fr and Rr, as shown in FIG. The amount of displacement along the front-rear direction Fr-Rr is such that the cutter bit 5 formed on the cutter spoke 8 retracts from the hole of the spoke support portion 4 to the rear Rr, and the cutter spoke 8 is displaced in the longitudinal direction. This is the amount up to a position where the cutter bit 5 is not caught in the hole of the spoke support 4.

  Here, the division | segmentation spoke accommodation chamber 10 is formed in the width | variety which can isolate | separate each division | segmentation cutter spoke 8a, 8b from the exterior, and can accommodate those longitudinal directions along the radial direction. .

  Further, an opening 11 having a size sufficient to allow the divided cutter spokes 8 a and 8 b slid in the sliding direction (radial direction) to enter the divided spoke accommodating chamber 10 on the outer peripheral surface of the divided spoke accommodating chamber 10. A water stop gate (for example, a knife gate) 12 formed between the closed position that covers the opening 11 in a watertight manner and the open position that exposes the opening 11 is provided.

  When the water stop gate 12 is in the open position, that is, when the divided cutter spokes 8a and 8b are taken into and out of the storage chamber 10 through the opening 11, the inside and outside of the storage chamber 10 communicate with each other through the opening 11, Earth or sand or water may flow into the accommodation chamber 10 through the opening 11.

  Therefore, in a state where the water stop gate 12 is in the closed position, the storage chamber 10 is filled with a liquid such as water applied with a pressure against the pressure at which these earth and sand and water flow into the storage chamber 10 in advance. By providing a predetermined pressurizing means (not shown) (for example, a pump configured to send water at a predetermined pressure and a water injection pipe having one end opened inside the storage chamber and the other end connected to the pump). Even if the water stop gate 12 is opened, it is possible to suppress or prevent these external earth and sand and water from flowing into the storage chamber 10.

  As shown in FIGS. 3 (a) and 3 (b), the divided cutter spokes 8a and 8b that are adjacent to each other in the radial direction R of the face plate 3 have concave and convex shapes 8d and 8c that are engaged in the rotational direction around the axis. I have.

  That is, for example, the Ω-shaped convex shape 8c is formed on the portion of the inner peripheral side divided cutter spoke 8a connected to the outer peripheral side divided cutter spoke 8b, while the outer peripheral side divided cutter spoke 8b A portion connected to the inner peripheral divided cutter spoke 8a is engaged with and connected to a Ω-shaped convex shape 8c, and a constricted concave shape 8d for receiving the Ω-shaped convex shape 8c (FIG. 3 ( b)) is formed.

  Therefore, in the face board 3, when the divided cutter spokes 8a and 8b are engaged with each other by the concave and convex shapes 8d and 8c, the cutter spokes are rotated around the axis as an integral cutter spoke of the original length before the division. It can prevent that the excavation efficiency by 8 falls.

  Note that the engagement of the convex shape 8c of the inner peripheral side divided cutter spoke 8a and the concave shape 8d of the outer peripheral side divided cutter spoke 8b is such that only the inner peripheral side divided cutter spoke 8a is displaced rearward Rr. Or only the division | segmentation cutter spoke 8b of an outer peripheral side disengages by displacing to the front Fr, and both engagement does not remove | deviate by operation | movement other than these.

  Further, predetermined engagement protrusions 8e and 8f are formed on the side surfaces of the divided cutter spokes 8a and 8b, and each divided cutter spoke 8a and 8f accommodated in the divided spoke accommodation chamber 10 is formed in the divided spoke accommodation chamber 10. A traction tool 13 is provided as a moving means that engages with the engaged protrusions 8e and 8f of 8b and sequentially moves the divided cutter spokes 8a and 8b in the axial direction (Fr-Rr).

  The traction tool 13 has a cross section (SS cross section) having an I shape shown in FIG. 3D or a rail cross section similar to the rail cross section shown in FIG. It is formed and has sufficient rigidity with respect to the weight of the cutter spoke 8 acting on the traction tool 13.

  Next, the operation of the shield machine 1 of the present embodiment will be described with reference to FIGS. 2 and 4 showing a schematic operation and FIGS. 5 and 6 showing a detailed operation.

  First, the state of A1 indicated by a two-dot chain line in FIG. 2 (b) indicates a use state when performing normal excavation work and excavation work. In this usage state A1, the cutter spoke 8 has its cutter bit 5 protruding forward Fr from the hole of the spoke support portion 4, and the cutter bit 5 protruding from the spoke support portion 4 is positioned further forward. Excavate ground not shown.

  When replacing the cutter bit 5, first, the entire cutter spoke 8 is displaced rearward Rr to the retracted position indicated by the solid line, and the cutter bit 5 is detached from the hole of the spoke support portion 4 (A2). It becomes.

  At this time, the water stop gate 12 of the storage chamber 10 is closed, and the opening 11 is covered with the water stop gate 12.

  Here, in detail, as shown in FIG. 5A, water is injected into the storage chamber 10 by the pressurizing means, and the pressure of the water W inside the storage chamber 10 and the storage through the water stop gate 12 The balance with the pressure outside the chamber 10 is taken, and when the water stop gate 12 is opened, the outside earth and sand and water are prevented from flowing into the housing chamber 10 at once.

  Next, as shown in FIG. 4 (a), the water stop gate 12 is opened, the inside and outside of the storage chamber 10 communicate with each other through the opening 11, and the cutter spokes 8 extend along the radial direction R (the axial center of the center shaft 2). The cutter spoke 8 a on the inner peripheral side is accommodated in the accommodating chamber 10.

  As described above, when the water stop gate 12 is opened, that is, when the inside and outside of the storage chamber 10 are in communication with each other through the opening 11 as shown in detail in FIG. Since the pressure of the water W filled inside and the pressure due to the excavated sediment and water outside the storage chamber 10 are balanced to some extent, even if heavy objects such as sediment flow into the storage chamber 10, It is possible to prevent inflow of dust.

  In addition, since the speed at which earth and sand flows in is reduced, it is possible to prevent the interior of the storage chamber 10 from being damaged by an impact due to the inflow of earth and sand.

  Then, as shown in FIG. 5 (c), after the traction tool 13 is sent out to the front part in the storage chamber 10, the entire cutter spoke 8 is slid in the radial direction, and the inner-side cutter spoke 8a is stored. At this time, as shown in FIG. 5 (c), the engaged protrusion 8 e formed on the side surface of the cutter spoke 8 a is engaged with the traction tool 13.

  Next, as shown in FIG. 4B, the inner-side cutter spoke 8a accommodated in the accommodation chamber 10 moves to the rear Rr in the accommodation chamber 10, and at this time, the inner-side divided cutter spoke 8a. The engagement of the concavo-convex shape between the outer peripheral side divided cutter spoke 8b is released, and the inner peripheral side divided cutter spoke 8a is completely separated from the outer peripheral side divided cutter spoke 8b.

  Specifically, as shown in FIG. 5D, when the traction tool 13 engaged with the engaged protrusion 8e of the divided cutter spoke 8a is displaced rearward, the divided cutter spoke 8a is also displaced rearward. At this time, the engagement between the convex shape 8c of the inner peripheral side divided cutter spoke 8a and the concave shape 8d of the outer peripheral side divided cutter spoke 8b shown in FIG. Are separated.

  Since the inner-side divided cutter spoke 8a has moved to the rear part of the storage chamber 10, the space immediately below the outer-side divided cutter spoke 8b in the storage chamber 10 (water W is filled) is vacant. As shown in FIG. 4C, the divided cutter spoke 8b on the outer peripheral side descends directly below and is accommodated in this vacant space, the water stop gate 12 moves to the closed position, and the opening 11 opens. Covered, the storage chamber 10 is isolated from the outside in a watertight manner.

  Specifically, as shown in FIG. 6 (a), after the outer divided cutter spoke 8b is accommodated in the accommodating chamber 10, the water stop gate 12 is closed and the opening 11 is opened as shown in FIG. 6 (b). Then, a discharge means (not shown) including a pump that sucks at a predetermined suction pressure and a discharge pipe that has one end opened at the bottom inside the storage chamber and the other end connected to the pump. ), The earth and sand flowing into the storage chamber 10 while the opening 11 is open is discharged to the outside of the storage chamber 10 together with the water W that has been poured.

  And after discharge | emissioning earth and sand etc., as shown in the figure (c), by opening the rear side gate 14 of the storage chamber 10, the cutter bit of each division | segmentation cutter spoke 8a, 8b accommodated in the storage chamber 10 is carried out. An operator M for exchanging 5 can enter and exit the storage chamber 10, and the operator M who has entered the storage chamber 10 can move the cutter bit in the storage chamber 10 as shown in FIG. 5 replacement operations can be performed.

  In addition, as for the discharge means mentioned above, the pressurization means which pours water in the storage chamber 10 may serve as the function, for example.

  As described above, according to the shield machine 1 according to the present embodiment, the interior of the accommodation chamber 10 is isolated from the outside. Therefore, each division accommodated safely and easily inside the divisional spoke accommodation chamber 10. The cutter bits 5 of the cutter spokes 8a and 8b can be exchanged.

  Moreover, since the cutter spoke 8 is divided into two portions 8a and 8b having a predetermined length in the longitudinal direction, each of the divided cutter spokes 8a and 8b obtained by dividing in this way is a cutter spoke 8 respectively. The length is shorter than the overall length.

  On the other hand, since the divided spoke accommodating chamber 10 for accommodating the divided cutter spokes 8a and 8b is formed at the center of the face board 3, the divided cutter spokes 8a and 8b are respectively slid in the longitudinal direction to divide the spokes. It can be stored in the storage chamber 10.

  The storage chamber 10 for storing the cutter spokes 8a and 8b and exchanging the cutter bit 5 has a height (diameter) sufficient to store the divided cutter spokes a and 8b shorter than the entire length of the cutter spoke 8. Since the diameter should be as small as possible, the surface of the center shaft 2 in the face plate 3, that is, the fishtail 6, should be made as small as possible, and the length of the cutter spoke 8 for substantial excavation should be secured as usual. And excavation efficiency is not reduced.

  Further, even if the divided spoke accommodating chamber 10 is made larger than the divided cutter spokes 8a and 8b to accommodate the excavation efficiency, the cutter bit 5 in the accommodating chamber 10 is not greatly impaired. A wide work space for replacement can be secured, and the replacement workability can be improved.

  In addition, by arranging all the divided cutter spokes 8a and 8b in the thickness direction in the storage chamber, the depth of the storage chamber 10 can be obtained as compared with the case where the divided cutter spokes 8a and 8b are stored in the longitudinal direction. The length (the length along the axial direction of the cylindrical shape) can be made sufficiently small.

  Further, a discharge means (not shown) for discharging the earth and sand flowing into the divided spoke storage chamber 10 to the outside is connected to the inside of the divided spoke storage chamber 10, and the divided cutter spokes 8 a and 8 b are put into and out of the storage chamber 10 through the opening 11. In this case, even if external soil or water flows into the storage chamber 10 through the opening 11, after the water stop gate 12 is moved to the closed position, the sediment or water in the storage chamber 10 is removed by the discharge means. 10 can be discharged to the outside, and when exchanging the cutter bit in the storage chamber 10, the work space can be prevented from being occupied with earth, sand, water, etc., and the work space can be secured reliably. it can.

  Moreover, the length along the axial direction of the divided spoke accommodation chamber 10 is formed longer than the total width of the width along the axial direction of at least two divided cutter spokes 8a and 8b. The divided cutter spokes 8a and 8b can be accommodated compactly by arranging them in the width direction.

  In addition, although detailed description was abbreviate | omitted, what is necessary is just to use well-known drive mechanisms (not shown), such as a winch and a jack, etc. for the slide movement of the cutter spoke 8 (divided cutter spoke 8a, 8b).

It is a mimetic diagram showing a shield machine concerning one embodiment of the present invention. (A) is the front view which looked at the shield machine shown in FIG. 1 from the front end surface side, (b) is sectional drawing which represented typically the cross section along the MM line in (a), (c). Represents a cross-sectional view schematically showing a cross section taken along line NN in (a). It is a figure which shows the detail of the cutter spoke of the shield machine shown in FIG. It is a figure which illustrates roughly the effect | action of the shield machine shown in FIG. It is FIG. (1) explaining the detailed effect | action of a shield machine. It is a figure (the 2) explaining the detailed effect | action of a shield machine.

Explanation of symbols

2 Center shaft 5 Cutter bit 6 Fish tail 7 Fish tail bit 8 Cutter spokes 8a, 8b Divided cutter spoke 10 Divided spoke accommodation chamber 11 Opening 12 Water stop gate R Radial direction (center axis direction)
Fr front Rr rear

Claims (5)

It has a generally cylindrical shape as a whole, and a plurality of radially extending cutter spokes are disposed on the front end surface facing the object to be excavated, and the front end surface is around the axis of the cylindrical shape. In the shield machine with a large number of cutter bits installed on the outer surface of the cutter spoke,
The cutter spoke is divided into a plurality of portions having a predetermined length in the longitudinal direction and is arranged to be slidable in the longitudinal direction,
Wherein the front end face, the heart portion in including an axis of the cylindrical shape, each of the divided cutter spokes obtained by dividing the predetermined length, divided spoke accommodating chamber for accommodating and isolated from the outside is formed,
The length along the axial direction of the divided spoke accommodation chamber is formed to be longer than the total width of the width along the axial direction of at least all the divided cutter spokes, and a plurality of the divided cutter spokes are simultaneously formed. A shield machine that is formed so as to be accommodated side by side in the width direction .   On the outer peripheral surface of the divided spoke housing chamber, an opening having a size for allowing the divided cutter spoke that has been slid in the sliding direction to pass outside the divided spoke housing chamber is formed, and the closed position covers the opening in a watertight manner. The shield machine according to claim 1, further comprising a water stop gate that is displaced between an opening position that exposes the opening.   The shield excavator according to claim 1 or 2, wherein discharge means for discharging the earth and sand flowing into the divided spoke housing chamber to the outside is connected to the inside of the divided spoke housing chamber. Between the divided cutter spokes adjacent to each other in and out in the radial direction of the front end surface, either one of claims 1 or et 3, characterized in that it comprises an uneven shape which engages with respect to the rotational direction of the axis 1 The shield machine according to item. Each of the divided cutter spokes is formed with a predetermined engaged portion, and the divided spoke accommodating chamber is engaged with an engaged portion of each divided cutter spoke accommodated in the divided spoke accommodating chamber. shield machine as claimed in any one of claims 1 or et 4, characterized in that moving means for sequentially moving each of these divided cutter spokes in the axial direction is provided.

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