JP4843803B2 - Cutter bit replacement method, cutter bit, cutter bit loading mechanism, and shield machine - Google Patents

Description

  The present invention relates to a cutter bit replacement method, a cutter bit, a cutter bit loading mechanism, and a shield machine.

  In recent years, as the shield tunnel excavation work becomes longer, maintenance of the cutter bit of the shield machine has become a problem. Therefore, as a countermeasure against this problem, it is conceivable to replace the cutter bit during excavation. Various methods for exchanging the cutter bit have been proposed.

As one of the methods, the following has been proposed.
Each cutter bit mounting groove extending radially from the center of the rotary cutter head is provided. A bit exchange box is installed at the cutter rotation center side end of the cutter bit mounting groove, a new cutter bit for replacement is inserted into the bit exchange box, and the new cutter bit is moved in the radial direction of the cutter head. The new cutter bit is set on the cutter head and the outermost diameter cutter bit is pushed out from the cutter head (see, for example, Patent Document 1).
JP 2003-232192 A

The one described in Patent Document 1 inserts a new cutter bit into the cutter bit mounting groove from the cutter rotation center side and pushes the side surface of the existing cutter bit, thereby sequentially moving the existing cutter bit in the radially outward direction. Try to extrude.
By the way, there is a phenomenon in which inclusions such as earth and sand enter the contact surface between the new cutter bit and the existing cutter bit. If inclusions such as earth and sand enter between the new cutter bit and the existing cutter bit, the following problems occur.
When inclusions are present on the side surfaces of adjacent cutter bits, the length from the innermost cutter bit to the outermost cutter bit becomes longer. For this reason, the excavation cross-sectional area becomes large, and there is a possibility that a problem that the excavation diameter does not become as planned may occur.

Also, the back side of the cutter bit is usually provided with unevenness, and the cutter bit is prevented from shifting by engaging the unevenness of the back side of the cutter bit with the unevenness of the fixing plate provided on the back side of the cutter bit. is doing.
However, if there are inclusions on the side surface of the adjacent cutter bit, the pitch between the unevenness on the back side of the cutter bit and the unevenness of the fixing plate will be shifted, so that these unevennesses will not be able to engage, preventing the cutter bit from shifting. The function is not fully exhibited, which hinders normal driving of the cutter bit exchange mechanism.

  The present invention has been made to solve such a problem, and is a technique for preventing an inclusion from entering between an existing cutter bit and a new cutter bit when the cutter bit is loaded, and removing the adverse effect of the inclusion. The purpose is to provide.

(1) A method for removing the adverse effect of inclusions when loading a cutter bit according to the first embodiment of the present invention is to replace the cutter bit mounting groove extending radially from the center portion of the cutter head from the end portion on the cutter rotation center side. The new cutter bit is inserted and the new cutter bit is pushed out in the radial direction to load the new cutter bit into the cutter head. When the cutter head is loaded, there is an inclusion between the new cutter bit and the existing cutter bit. A method of preventing the intrusion of inclusions by preventing intrusion,
It is characterized in that earth and sand are removed from the surfaces where the cutter bits come into contact with each other.

(2) Also, in the above described (1), in order to remove earth and sand from the surfaces where the cutter bits contact each other, the new cutter bit side and / or the contact surface between the new cutter bit and the existing cutter bit and / or A recess is provided on the existing cutter bit side.

(3) Further, in the above-described (1) or (2), in order to remove earth and sand from the surfaces where the cutter bits contact each other, fluid is jetted between the new cutter bit and the existing cutter bit. It is characterized by that.

(4) The cutter bit according to the first aspect of the present invention is configured such that a new cutter bit for replacement is inserted from a cutter rotation center side end into a cutter bit mounting groove extending radially from the center portion of the cutter head, A cutter bit of a shield machine having a cutter bit loading mechanism for loading a new cutter bit into a cutter head by extruding the new cutter bit in a radially outward direction,
A concave portion is provided on the new cutter bit side and / or the existing cutter bit side on the contact surface between the new cutter bit and the existing cutter bit.

(5) The cutter bit loading mechanism according to the first aspect of the present invention includes a cutter bit mounting groove extending radially from the center of the cutter head, a cutter bit mounted in the cutter bit mounting groove, and a new replacement An extrusion jack for extruding the cutter bit in the radially outward direction,
The cutter bit is characterized in that a concave portion is provided on the new cutter bit side and / or the existing cutter bit side on the contact surface between the new cutter bit and the existing cutter bit.

(6) Further, in the cutter bit loading mechanism according to the above (5), fluid ejecting means for ejecting fluid for removing inclusions such as earth and sand is provided between the existing cutter bit and the replacement cutter bit. It is characterized by that.

(7) A shield machine according to the first embodiment of the present invention includes the cutter bit loading mechanism described in (5) or (6) above.

  In the present invention, when the cutter bit is loaded, inclusions are prevented or suppressed from entering the surfaces where the new cutter bit and the existing cutter bit come into contact with each other. Since the inclusions are prevented or suppressed from entering the surfaces where the adjacent cutter bits inserted into the grooves come into contact with each other, adverse effects of inclusions such as earth and sand can be removed or reduced.

  FIG. 1 is an axial cross-sectional view of a front trunk portion of a shield machine according to an embodiment of the present invention. First, the configuration of the shield machine according to the present embodiment will be outlined based on FIG. In this specification, “front” and “rear” mean the front and rear of the shield machine. Further, “upper” and “lower” mean “upper” and “lower” in the drawing.

The shield machine according to the present embodiment includes a cutter head 3 that is rotatably attached to the front end of a cylindrical skin plate 1. The cutter head 3 includes a cylindrical portion 5 provided at the center thereof, a cutter pork 7 extending radially from the cylindrical portion 5, and a rotating cutter 9 provided at the front end of the cylindrical portion 5.
The cutter spoke 7 is provided with a cutter bit 11 and a copy cutter 13 which are loaded by a cutter bit loading mechanism which will be described later. The cylindrical portion 5 is rotationally driven by a cutter drive motor 17 via a gear 15. The cylindrical part 5 is provided with a rotary joint 19 for connecting a hydraulic system.

  A partition wall 21 is provided at a position slightly rearward from the front end of the skin plate 1. Excavated sediment accumulates between the cutter head 3 and the partition wall 21, and a screw conveyor 23 is provided for discharging the excavated sediment.

FIG. 2 is an enlarged view showing an A portion surrounded by a circle in FIG. Hereinafter, the cutter bit loading mechanism will be described with reference to FIG.
The cutter bit loading mechanism according to the present embodiment includes a cutter bit mounting groove (not shown) formed in the cutter pork 7, a cutter bit 11 mounted in the cutter bit mounting groove, and a new cutter bit when the cutter bit is loaded. A watertight box 25 for charging 11A and a push-out jack 27 for pushing the new cutter bit 11A charged in the watertight box 25 in the radially outward direction are provided. And the cutter bit 11 is provided with the recessed part 11f in the new cutter bit side and the existing cutter bit side in the contact surface of the new cutter bit 11A and the existing cutter bit 11B. (When a cutter bit is generally indicated, it is referred to as a cutter bit, and a reference numeral 11 is attached. When a cutter bit to be loaded for replacement is indicated, it is assigned a reference numeral 11A as a new cutter bit, and abuts against the new cutter bit 11A. (When an existing cutter bit to be used is indicated, it is referred to as an existing cutter bit and denoted by reference numeral 11B.)

In addition, the cutter bit loading mechanism according to the present embodiment includes a sliding opening / closing gate 29 that opens and closes communication between the watertight box 25 and the cutter pork 7. Furthermore, the cutter bit loading mechanism according to the present embodiment includes a fluid ejection nozzle 31 that ejects water toward the inner end face of the existing cutter bit 11B.
Hereinafter, each configuration of the cutter bit 11 loading mechanism will be described in more detail.

(1) Cutter bit mounting groove The cutter bit 11 mounting groove is provided in the cutter pork 7 of the cutter head 3, and the cutter bit 11 is cut in a posture in which the bit provided at the front end of the cutter bit 11 is positioned forward. 7 is held.

(2) Cutter Bit The cutter bit 11 is inserted into a cutter bit mounting groove provided in the cutter pork 7. The cutter bit 11 is inserted into the cutter bit insertion groove from the radial center side and sequentially moves in the radially outward direction, and the cutter bit 11 at the outermost diameter portion is detached from the cutter pork 7 and discarded.

  3A and 3B are explanatory views of the cutter bit 11. FIG. 3A is a side view, FIG. 3B is a plan view, and FIG. 3C is a bottom view. In FIG. 3, the upper and lower sides of the cutter bit 11 are drawn in reverse to FIG. 2. The cutter bit 11 is inserted so as to be turned upside down at the adjacent cutter pork. This is because the L-shaped cutter bits 11 installed in adjacent cutter porks are arranged in a staggered manner between adjacent ones so that no gap is generated in the circumferential direction. FIG. 3 shows the posture of the cutter bit 11 loaded in the cutter spoke adjacent to the cutter spoke 7 shown in FIG.

As shown in FIG. 3B, the cutter bit 11 is substantially T-shaped in a plan view, and a portion 11a corresponding to the lateral side of the T-shape is inserted into the bit insertion groove of the cutter pork 7, A portion 11b corresponding to the vertical side of the T-shape projects forward, and the bit 12 is positioned at the tip.
Further, as shown in FIG. 3A, the cutter bit 11 is L-shaped in a side view, and has a valley-shaped engaging portion that is recessed (recessed) toward the front side on the rear side. 11c is formed. As will be described later, the locking portion 11c is locked with the fixing plate 33 to prevent the cutter bit 11 from being displaced in the radial direction.

Further, as shown in FIG. 3A, the cutter bit 11 has a mountain shape at one of the upper and lower portions when viewed from the side surface and a valley shape at the other (in FIG. 3, the upper portion 11d). Is a Yamagata, and the lower part 11e is a valley). By providing the valleys in the upper and lower parts in this way, the peaks and valleys of the mutually adjacent cutter bits 11 are engaged with each other to prevent the adjacent cutter bits 11 from being displaced in the front-rear direction.
Further, the cutter bit 11 is formed with a recessed portion 11f into which earth and sand can enter in the upper and lower portions in a side view. The concave portion has a cylindrical cross section (see FIGS. 3B and 3C), and the bottom of the concave portion has an inverted conical shape (see FIG. 3A).

(3) Fixed plate The fixed plate 33 is a plate-like body provided on the rear surface side of the cutter bit 11, and is formed in a shape that is locked to the locking portion 11c on the rear surface of the cutter bit 11. A fixed jack 35 is provided behind the fixed plate 33, and the locking force between the cutter bit 11 and the fixed plate 33 is set to an appropriate strength by pressing the fixed plate 33 forward. The appropriate strength is a strength that allows the cutter bit 11 to be loaded by moving backward when the cutter bit 11 is loaded, and prevents the cutter bit 11 from being displaced after the cutter bit 11 is loaded.

(4) Honeycomb box The watertight box 25 is installed in the cylindrical portion 5 and opens and closes communication between the inside of the machine and the outside when the cutter bit 11 is loaded into the cutter pork 7.
The watertight box 25 has an open / close door 39 for inserting a new cutter bit 11A on the inside of the machine, and an opening 41 on the surface facing the cutter pork 7.
In addition, a support (not shown) that holds the posture of the inserted cutter bit 11 is provided inside the watertight box 25.
In addition, an extrusion jack 27 for pushing out the cutter bit 11 inserted in the box toward the cutter pork 7 is provided at the upper part of the honey-box 25.

(5) Sliding Open / Close Gate The slide open / close gate 29 is provided to face the opening 41 of the watertight box 25 and opens / closes communication between the opening 41 of the watertight box 25 and the outside of the machine.
The sliding opening / closing gate 29 performs the opening / closing operation by sliding the gate portion 46 back and forth in the axial direction with a jack 47 (see FIG. 1).

(6) Fluid Injecting Nozzle The fluid injecting nozzle 31 eliminates earth and sand by injecting water between the end face of the existing cutter bit 11B and the gate portion 46, and loads the existing cutter bit 11A when the new cutter bit 11A is loaded. The inclusions are prevented from entering between 11B and the new cutter bit 11A.
The timing of injecting water is when at least the new cutter bit 11A and the existing cutter bit 11B are in contact with each other, and may be constantly injected.
In addition, it is desirable that the jetting power of water can be adjusted as appropriate.

FIGS. 4-8 is explanatory drawing of the loading method of the cutter bit 11 in this Embodiment comprised as mentioned above.
Hereinafter, a method of loading the cutter bit 11 will be described with reference to FIGS.
When loading the cutter bit 11, as shown in FIG. 4, the opening / closing door 39 of the watertight box 25 is opened, and the new cutter bit 11 </ b> A is loaded into the watertight box 25. The posture of the new cutter bit 11A inserted into the watertight box 25 is maintained by the support. When the new cutter bit 11A is inserted into the watertight box 25, the watertight box is filled with water so that the pressure in the watertight box becomes equal to the outside of the machine. This prevents the natural ground from collapsing by opening the sliding gate 29 to prevent dirt and sand outside the machine from entering the watertight box when the inside of the watertight box communicates with the outside of the machine. It is to do.

  Although earth and sand are difficult to enter between the existing cutter bit 11B and the gate portion 46 of the sliding opening / closing gate 29, some earth and sand may enter. At that time, the earth and sand that has entered enters the recessed portion 11f provided at the upper end of the existing cutter bit 11B, and the structure is unlikely to exist on the upper end surface of the existing cutter bit 11B, that is, the contact surface with the new cutter bit 11A. ing.

  Water is injected from the fluid injection nozzle 31 before the new cutter bit 11A is inserted into the watertight box 25 and the sliding opening / closing gate 29 is opened. By spraying water, when the earth and sand are adhered to the upper end surface of the existing cutter bit 11B, this is removed, and it is more likely that earth and sand are present on the contact surface between the new cutter bit 11A and the existing cutter bit 11B. It can be surely prevented.

  Next, the sliding opening / closing gate 29 is opened (see FIG. 5). Then, the push-out jack 27 is extended to push the new cutter bit 11A toward the cut spoke 7 side. As a result, the new cutter bit 11A is held by the support in the watertight box 25 and pushed out to the existing cutter bit 11B side (see FIG. 6). When the push-out jack 27 is further extended, the lower end surface of the new cutter bit 11A comes into contact with the upper end surface of the existing cutter bit 11B (see FIG. 7). At this time, since the recessed portion 11f is also provided on the lower end surface of the new cutter bit 11A, even if there is some earth and sand, it enters the recessed portion 11f. Therefore, since there is no inclusion such as earth and sand between the lower end surface of the new cutter bit 11A and the upper end surface of the existing cutter bit 11B, both end surfaces are in direct contact with each other.

  In this state, when the extrusion jack 27 is further extended and the new cutter bit 11A is completely pushed out to the cutter spoke 7 side, the existing cutter bit 11B and the cutter bit 11 in the radially outward direction move in the radially outward direction, The cutter bit 11 located at the outer diameter is detached from the cutter spoke 7. At this time, since there is no inclusion such as earth and sand on the end face of each cutter bit 11, the radial length of the cutter bit 11 is in accordance with the standard. In addition, since there is no deviation in the pitch between the rear face of the cutter bit 11 and the peaks and valleys of the fixing plate 33, the fixing of the cutter bit 11 is firmly prevented by the fixing plate 33.

As described above, in the present embodiment, the concave portions 11f are provided on the upper and lower portions of the cutter bit 11, so that when the cutter bit is loaded, earth or sand is placed on the surface where the new cutter bit and the existing cutter bit come into contact with each other. Therefore, the length of the cutter bit 11 in the radial direction, that is, the excavation cross-sectional area becomes as initially planned. In addition, since there is no deviation in the pitch between the rear surface of the cutter bit 11 and the peaks and valleys of the fixing plate 33, the cutter bit 11 reliably engages with the fixing plate 33, thereby preventing the cutter bit from being displaced.

  Further, in the above-described embodiment, since the recessed portions are provided on both the upper and lower sides of the cutter bit 11, when the new cutter bit 11A and the existing cutter bit 11B are brought into contact with each other, the both recessed portions face each other. Therefore, even when the volume of the recessed portion becomes large and a large amount of earth or sand remains, they can enter the recessed portion, and inclusions are formed on the contact surfaces of the new cutter bit 11A and the existing cutter bit 11B. Can be prevented as much as possible.

Furthermore, by providing the recessed portions on both the upper and lower sides of the cutter bit 11, the cutter bit 11 can be installed in any of the cut spokes 7, which is convenient. This point will be described in more detail. As described above, the direction of insertion of the cutter bit 11 in the adjacent cutter pork 7 is reversed inside and outside the diameter. Therefore, when the recessed portion 11f is provided only on one of the upper and lower sides of the cutter bit 11, there is a recessed portion 11f on the lower surface side of the new cutter bit 11A in a certain cutter pork, and the existing cutter bit 11B in the adjacent cutter pork. The recessed portion 11f is present on the upper surface side. In consideration of the fact that the recessed portion 11f is preferably present on the lower surface side of the new cutter bit 11A so as to make it difficult for inclusions to exist between the new cutter bit 11A and the existing cutter bit 11B. For this purpose, a cutter bit 11 to be loaded into a certain cutter pork 7 is provided with a concave portion 11f on the upper side, and a cutter bit 11 to be loaded into an adjacent cutter pork 7 is provided with a concave portion 11f on the lower side. The type of the cutter bit 11 to be loaded is different, which is complicated.
In this respect, if concave portions are provided on both the upper and lower sides of the cutter bit 11, it is convenient because the same type of cutter bit can be loaded in any of the spokes.

  However, even if the recessed portion 11 f is provided on either the upper or lower side of the cutter bit 11, a certain effect can be obtained. FIG. 9 and FIG. 10 are diagrams showing examples provided on either the upper or lower side. The example shown in FIG. 9 is an example provided at the bent portion of the cutter bit 11, and FIG. 10 is an example provided at the end.

Moreover, the recessed part 11f provided in the edge part of the cutter bit 11 does not need to be a single thing, For example, as shown in FIG. 11, you may make it provide several recessed part 11f.
Further, the recessed portion 11f provided at the end of the cutter bit 11 is not limited to the one having a hole as in the above-described example. For example, as shown in FIG. 12, a part of the peripheral wall of the recessed portion 11f is removed. Such a hollow type may be used.

It is explanatory drawing of the front-end part of the shield machine based on one embodiment of this invention. It is an enlarged view of the A section circled in FIG. It is explanatory drawing of the cutter bit in one embodiment of this invention. It is explanatory drawing explaining the process of the cutter bit replacement | exchange method in one embodiment of this invention in time series (the 1). It is explanatory drawing explaining the process of the cutter bit replacement | exchange method in one embodiment of this invention in time series (the 2). It is explanatory drawing explaining the process of the cutter bit exchange method in one embodiment of this invention in time series (the 3). It is explanatory drawing explaining the process of the cutter bit replacement | exchange method in one embodiment of this invention in time series (the 4). It is explanatory drawing explaining the process of the cutter bit exchange method in one embodiment of this invention in time series (the 5). It is explanatory drawing of the other aspect of the cutter bit which concerns on one embodiment of this invention. It is explanatory drawing of the other aspect of the cutter bit which concerns on one embodiment of this invention. It is explanatory drawing of the other aspect of the cutter bit which concerns on one embodiment of this invention. It is explanatory drawing of the other aspect of the cutter bit which concerns on one embodiment of this invention.

Explanation of symbols

    1 Skin plate, 3 Cutter head, 5 Cylindrical part, 9 Rotating cutter, 11 Cutter bit, Recessed part 11f, 17 Cutter drive motor, 25 Watertight box, 27 Extrusion jack, 29 Sliding open / close gate, 31 Fluid injection nozzle, 33 Fixed Board, 35 fixed jack.

Claims (6)

Insert a new cutter bit for replacement into the cutter bit mounting groove extending radially from the center of the cutter head of the shield machine, and push the new cutter bit in the radial direction. A method for replacing a cutter bit to be loaded on a head,
Of the surfaces where the new cutter bit and the existing cutter bit come into contact with each other, a recess is provided on the surface of at least one side of the new cutter bit and the existing cutter bit so that earth and sand can enter, and the new cutter bit is loaded into the cutter head. In this case, the cutter bit replacement method is characterized in that earth or sand or the influence thereof is previously removed from the surface where the new cutter bit and the existing cutter bit abut.   2. The method for replacing a cutter bit according to claim 1, wherein when at least the new cutter bit and the existing cutter bit come into contact with each other, fluid is jetted between the new cutter bit and the existing cutter bit. Insert the new cutter bit for replacement into the cutter bit mounting groove extending radially from the center of the cutter head from the end of the cutter rotation center, and push the new cutter bit in the radially outward direction to cut the new cutter bit. A cutter bit of a shield machine having a cutter bit loading mechanism for loading a head,
A cutter bit comprising a recess on the new cutter bit side and / or the existing cutter bit side on the contact surface between the new cutter bit and the existing cutter bit. A cutter bit mounting groove extending radially from the center of the cutter head, a cutter bit mounted in the cutter bit mounting groove, and an extrusion jack for extruding a new cutter bit for replacement in a radially outward direction,
The cutter bit loading mechanism of a shield machine, wherein the cutter bit is provided with a recess on the new cutter bit side and / or the existing cutter bit side on the contact surface between the new cutter bit and the existing cutter bit. 5. The cutter bit loading mechanism according to claim 4 , wherein a fluid jetting means for jetting a fluid for removing inclusions such as earth and sand is provided between the existing cutter bit and the replacement cutter bit. A shield machine equipped with the cutter bit loading mechanism according to claim 4 or 5 .

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