JP2007197998A - Cutter bit mounting structure and maintenance method - Google Patents

Abstract

A cutter capable of dealing with a cutter head without damaging the cutter head and its nearby equipment when the bit is worn, and capable of exchanging the bit without an operator coming out to the face of the cutter head when the bit wear further progresses. A bit mounting structure and a maintenance method are provided.
When a bit body 10 is worn by a predetermined amount, a jack 11 is extended according to the wear amount and a rod 9 is protruded from a guide hole 8 toward the face, so that the cutting radius by the bit body 10 is reduced before wear. When the wear of the bit body 10 further proceeds, the jack 11 is contracted, the jack 11 is separated from the rod 9 on the side opposite to the cutter head 2, and the rod 9 is pulled out from the guide hole 8. Were replaced individually or integrally with the rod 9.
[Selection] Figure 2

Description

  The present invention relates to a mounting structure and a maintenance method for a cutter bit attached to a cutter head of a shield machine, and more particularly to a mounting structure and a maintenance method for a cutter bit corresponding to long-distance construction.

  A shield machine is generally equipped with a cutter head that is driven to rotate around an axis along the direction of excavation, and the face is cut by a bit attached to the cutter head. Wear becomes a problem. In particular, when excavating long-distance ground such as granite for a long distance, wear on the outermost bit of the cutter head becomes significant.

  In Patent Document 1, a guide cylinder having an opening on the face side is provided in the cutter head, and two bits formed in a substantially cylindrical shape are inserted in series in the guide cylinder, and these bits are sequentially pushed out. Is provided with a jack in the cutter head. According to this, the excavation is performed with the front end of the front bit protruding from the guide tube, and if the bit is worn to the limit, the jack is extended and the front bit is pushed out of the guide tube and discarded. The excavation can be continued by causing the tip of the rear bit to protrude from the guide tube.

  In Patent Document 2, a guide cylinder having an opening on the face side is provided in the cutter head, a bit formed in a substantially cylindrical shape is inserted into the guide cylinder, and a jack for pushing the bit to the face side is described above. There is a description in which a positioning mechanism is provided inside the cutter head and is provided between the guide cylinder and the bit to hold the bit in a predetermined position where the bit is pushed out. According to this, excavation is performed with the tip of the bit protruding from the guide tube, and when the bit is worn out by a predetermined amount, the jack is extended and the bit is pushed out to return the projection amount to the original position and fixed by the positioning mechanism. , Can continue to dig.

JP-A-6-229194 Japanese Patent No. 2914563

  By the way, in the thing of the literature 1, since the worn bit is pushed out to the face side and discarded, the pushed bit interferes with the rotating cutter head and damages the cutter head and its nearby equipment (screw conveyor, etc.). There is a possibility to make it. Moreover, it is not preferable from an environmental viewpoint.

  In the case of the document 2 described, when the extruded bit is worn again, it is necessary to replace the bit. For this replacement, an operator must come out to the face side of the cutter head. A large-scale ground improvement will be required in the vicinity.

  Therefore, an object of the present invention is to cope with the bit head when it is worn without damaging the cutter head and the equipment in the vicinity thereof, and when the bit wear further, the worker does not come out on the face side of the cutter head. It is an object to provide a cutter bit mounting structure and a maintenance method capable of exchanging bits.

  In order to achieve the above object, a first aspect of the present invention is a mounting structure of a cutter bit attached to a cutter head that is rotationally driven with respect to a face, and the face side and the anti-face side are communicated with the cutter head. The formed guide hole, the rod slidably inserted in the guide hole, the bit body attached to the end of the rod on the face side, and the end of the rod on the side opposite to the face can be disconnected. And a jack whose other end is pivotally supported on a part of the cutter head opposite to the face.

  It is preferable that the length of the rod body attached to the rod is set to be shorter than the distance from the opening edge of the guide hole on the opposite face side to the partition wall arranged behind the cutter head.

  The guide hole is formed on the outer peripheral side of the cutter head so as to incline radially outward from the counter-cut face side to the face side, and the bit body cuts the front face substantially in front of the outer peripheral edge of the cutter head. It is preferable that

  A second invention is a maintenance method of a cutter bit attached to a cutter head that is rotationally driven with respect to the face, a guide hole formed by communicating the face side and the anti-face side with the cutter head, A rod slidably inserted into the guide hole, a bit body attached to the end of the rod on the face side, and one end connected to the end of the rod on the side opposite to the face so as to be detachable Is provided with a jack pivotally supported on a portion of the cutter head opposite to the face, and when the bit body is worn by a predetermined amount, the jack is extended according to the amount of wear, whereby the tip of the worn bit body The protrusion length of the guide hole is returned to the pre-wear state, and when the bit body further wears, the jack is contracted, and the jack is raised on the opposite face side of the cutter head. Pulling said rod from said guide hole separately from the rod, is obtained so as to singly or integrally exchanged with the rod the bit body.

  A third invention is a maintenance method of a cutter bit attached to a cutter head that is rotationally driven with respect to the face, a guide hole formed by communicating the face side and the anti-face side with the cutter head, A rod slidably inserted into the guide hole, a bit body attached to the end of the rod on the face side, and one end connected to the end of the rod on the side opposite to the face so as to be detachable Is provided with a jack pivotally supported on a portion of the cutter head opposite to the face, and when the bit body is worn by a predetermined amount, the jack is extended according to the amount of wear, whereby the tip of the worn bit body The length of the protrusion from the guide hole is returned to the pre-wear state, and when the bit body further wears, the jack is contracted, and the rod is placed on the opposite face of the cutter head on the anti-face face side. Withdrawal from wellbore, the rod in a state disconnected from the jack, in which so as to singly or integrally exchanged with the rod the bit body.

  According to the present invention, when the bit body is worn, the worn bit body is not pushed out of the guide hole and discarded, but the jack is extended according to the wear amount to recover the protruding amount of the bit body. Therefore, it is possible to avoid damage to the cutter head and the equipment in the vicinity thereof due to the discarded bit body.

  Also, if the bit body wears further, contract the jack, disconnect the jack from the rod on the opposite side of the cutter head, and pull the rod out of the guide hole, so that the worker comes out to the cutter side of the cutter head. The bit body can be replaced without any problems.

  Preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  As shown in FIGS. 1 and 2, a cutter 1 of a shield machine has a cutter head 2 that is driven to rotate about an axis parallel to the direction of excavation, and a plurality of bits 3 attached to the cutter head 2. The face and sand cut by the bit 3 by the rotation of the head 2 is taken into the cutter chamber 5 on the side opposite to the face of the head 2 through the earth and sand intake 4 opened in the head 2.

  The cutter chamber 5 is formed between the back surface (anti-face face side) of the cutter head 2 and a partition wall 7 provided so as to partition the front portion in the cylindrical shield frame 6 in the front-rear direction. The earth and sand in the cutter chamber 5 is conveyed into the mine by a soil removal device (a mud discharge valve, a screw conveyor, etc.) (not shown) provided in the partition wall 7. The cutter head 2 is rotatably supported by the partition wall 7 and is rotationally driven by a motor and a gear mechanism (not shown).

  When a long distance is excavated by the shield machine equipped with the cutter 1, the bit 3 is worn, so that countermeasures are required. In particular, the bit 3 on the outer peripheral side of the cutter head 2 has a longer cutting path per one rotation of the head 2 than the bit 3 on the inner peripheral side. Therefore, the mounting structure according to the present embodiment is adopted for the outermost peripheral bit 30 of the cutter head 2. However, this mounting structure is not limited to the outermost peripheral bit 30, and may be adopted, for example, for the bit at the middle position in the radial direction of the cutter head 2.

  As shown in FIG. 2, the attachment structure of the cutter bit 30 according to the present embodiment includes a circular guide hole 8 formed in the cutter head 2 in communication between the face side and the anti-face side, and slides into the guide hole 8. One end is connected to the end of the rod 9 that can be inserted and can be projected and retracted on the face side, the bit body 10 attached to the end of the rod 9 on the face side, and the end of the rod 9 on the side opposite to the face. The other end is provided with a jack 11 pivotally supported by a portion of the cutter head 2 on the opposite face side.

  The guide hole 8 is formed on the outer peripheral side of the cutter head 2 so as to be inclined radially outward from the anti-cut face side to the face side. The guide hole 8 is formed to have a predetermined length so as to support the cutting reaction force transmitted from the bit body 10 to the rod 9 during the rotation of the cutter head 2.

  The rod 9 has a cylindrical body 91 slightly smaller in diameter than the guide hole 8 and longer than the guide hole 8, a mounting seat 92 for attaching the bit body 10 to the end portion on the face side, and a jack on the end portion on the opposite face side. 11 and a flange 93 for attaching 11. The length X (FIG. 4) of the rod 9 with the bit body 10 attached to the rod 9 (FIG. 4) is from the opening edge 81 on the opposite face side of the guide hole 8 to the partition wall 7 arranged behind the cutter head 2. Distance Y (FIG. 4). In the illustrated example, the length Z (FIG. 4) of the rod 11 with bit connected to the jack 11 is longer than the distance Y. However, Z = Y or Z <Y may be used.

  Returning to FIG. 2, the bit body 10 is attached to the mounting seat 92, and when the jack 11 has an intermediate stroke, the cutting part 101 at the tip cuts the face substantially in front of the outer peripheral edge of the cutter head 2. Furthermore, it is formed in a predetermined length. The bit body 10 has a shape that does not protrude from the outer peripheral surface of the cylindrical body 91 when viewed from the axial direction of the rod 9. This is to prevent the bit body 10 from being caught in the guide hole 8 when the bit-attached rod 19 is pulled out from the guide hole 8 to the opposite face side. The bit body 10 is a leading bit (a bit for forming a circular groove around the rotation axis of the head 2 on the face surface prior to a normal cutting bit) in the illustrated example. A normal cutting bit may be used.

  The jack 11 is accommodated in the cylinder 111, a disc-shaped head 112 provided at one end of the cylinder 111, a donut plate-shaped rod cover 113 provided at the other end of the cylinder 111, and the cylinder 111. And a working rod 115 that is connected to the piston 114 and is inserted through the hole of the rod cover 113. The jack 11 is connected to the rod 9 by abutting the flange 116 provided on the head 112 against the flange 93 of the rod 9 and tightening the bolt 13a, and is disconnected from the rod 9 by loosening the bolt 13a. The distal end portion of the operating rod 115 is supported via a pin 15 by a metal fitting 14 attached to a portion of the cutter head 2 on the opposite face side. That is, one end of the jack 11 is connected to the rod 9 by a bolt 13a so as to be able to be connected and disconnected, and the other end is pivotally supported by a metal fitting 14 on the opposite face side of the cutter head 2.

  When the bit body 10 is worn by a predetermined amount, the jack 11 is extended according to the amount of wear, and the protruding length from the guide hole 8 at the tip of the bit body 10 is returned to the state before wear. The extension means 12 for returning the cutting radius by the bit body 10 to the state before wear is connected. The extension means 12 includes an extension hydraulic hose 121 connected to a head side hydraulic chamber 117 defined in the cylinder 111 by a piston 114 and a head 112, and a hydraulic pump (not shown) for supplying oil to the hydraulic hose 121. ).

  When the bit body 10 further wears, the jack 11 is contracted to contract the jack 11 so that the jack 11 is separated from the rod 9 and the rod 9 is pulled out from the guide hole 8 on the opposite face side of the cutter head 2. Means 13 are connected. The contraction means 13 includes a contraction hydraulic hose 131 connected to a rod side hydraulic chamber 118 defined in a cylinder 111 by a piston 114 and a rod cover 113, and a hydraulic pump (not shown) for supplying oil to the hydraulic hose 131. Z)).

  Ends of the hydraulic hoses 121 and 131 are connected to a rotary joint (not shown) provided at the center of rotation of the cutter head 2, and each hydraulic hose is supplied from a hydraulic pump disposed behind (in the mine) of the partition wall 7. Oil can be supplied to and discharged from the hoses 121 and 131.

  The flanges 93 and 116 are formed in a rectangular shape as shown in FIG. 3 when viewed from the axial direction of the rod 9 or the jack 11, and one side thereof is in contact with the stop plate 16. The rotation stop plate 16 is fixed inside the cutter head 2 and prevents the rod 9 and the jack 11 from rotating about the axis thereof by the cutting reaction force applied to the bit body 10. It also functions as a guide when 11 moves in the axial direction. If the rod 9 has a polygonal cross section (such as a square) and the guide hole 8 is a polygonal hole, the stop plate 16 can be omitted.

  Returning to FIG. 2, the rod 9, jack 11, metal fitting 14, pin 15, stop plate 16, hydraulic hoses 121, 131, etc. described above are accommodated in the portion of the cutter head 2 on the opposite face side. A casing 17 is provided to protect against sediment in the chamber 5. A part of the casing 17 (the rear part of the jack 11) is a detachable lid member 171.

  The operation of the cutter bit mounting structure configured as described above, that is, the maintenance method of the cutter bit will be described.

  If the bit body 10 is worn by a predetermined amount during the excavation of the shield machine, the cutter head 2 stops rotating, and oil is supplied to the head side hydraulic chamber 117 through the extension hydraulic hose 121 shown in FIG. Is moved obliquely upward and leftward in the drawing according to the amount of wear of the bit body 10 to extend the jack 11. Thereby, the protrusion length from the guide hole 8 at the tip of the worn bit body 10 returns to the state before wear, and the cutting radius by the bit body 10 can be returned to the state before wear.

  In this way, when the bit body 10 is worn out by a predetermined amount, the worn bit body 10 is not pushed out of the guide hole 8 and discarded, but the jack 11 is extended according to the amount of wear to extend the protruding length of the bit body 10. Therefore, it is possible to avoid damage to the cutter head 2 and nearby equipment caused by the discarded bit body 10.

  Whether or not the bit body 10 is worn by a predetermined amount is estimated based on, for example, the digging distance of the shield machine. For example, the digging distance of the shield machine required for the bit body 10 to wear by the distance L between the upper surface of the flange 93 and the opening edge 81 of the guide hole 8 is obtained in advance by experiments, simulations, etc. If the excavation distance becomes that distance, the radius of cutting by the bit body 10 can be returned to the state before wear by extending the jack 11 to the distance L, that is, full stroke.

  After that, if the excavation is continued and the bit body 10 is further worn, the rotation of the cutter head 2 is stopped, and oil is supplied to the rod side hydraulic chamber 118 through the contracting hydraulic hose 131 as shown in FIG. The cylinder 111 is moved diagonally downward to the right in the drawing to contract the jack 11 (full stroke).

  If the jack 11 is contracted, the ground is improved by injecting chemicals into the soil near the cutter head 2. The ground improvement may be performed prior to the contraction of the jack 11, or these may be performed simultaneously.

  After the ground improvement, the manhole cover 71 provided on the partition wall 7 is removed, and a worker enters the cutter chamber 5 on the opposite face side of the cutter head 2 from the manhole 72 opened in the partition wall 7, and the cover member 171 of the casing 17. Remove.

  An operator in the cutter chamber 5 loosens the bolt 13a and disconnects the jack 11 from the rod 9, and then turns the jack 11 backward about the pin 15 as shown in FIG. Pull out the rod 19 with a bit into the space. Alternatively, the jack 11 may be detached from the bit-attached rod 19 and the pin 11 may be pulled out from the metal fitting 14 to remove the jack 11 and the bit-attached rod 19 may be pulled out into the space generated by the removal. Alternatively, the metal rod 14 may be removed and the bit-attached rod 19 may be separated from the jack 11 after being pulled out obliquely downward from the guide hole 8 while being integrated with the jack 11.

  Since the rod-attached rod 19 and the jack 11 integrally connected in this manner are subdivided into the rod-attached rod 19 and the jack 11, the rod-attached rod 19 pulled out from the guide hole 8 is narrow. It can be appropriately moved in the cutter chamber 5 for replacement work. That is, as shown in FIG. 4, the length X of the rod 19 with bit 19 is set to be shorter than the distance Y from the opening edge 81 of the guide hole 8 to the partition wall 7, so that the inside of the cutter chamber 5 of the rod 19 with bit Free movement in is ensured.

  In detail, the length Z of the assembly product in which the rod 19 with a bit 19 and the jack 11 are integrated is longer than the distance Y from the opening edge 81 of the guide hole 8 to the partition wall 7. If it remains as it is, the free movement in the cutter chamber 5 is difficult, but by separating this into the rod 19 with a bit and the jack 11, the rod 19 with a bit can be easily moved. Even when Z is substantially the same length as Y or slightly shorter than Y, it is difficult to move freely in the cutter chamber 5 if the assembled product remains as it is. As a result, the free movement of the rod 19 with bit is ensured.

  Returning to FIG. 5, when the jack 11 is rotated around the pin 15 or moved by removing the pin 15, or when the bracket 14 is removed and the integrated product of the rod 19 with the bit 19 and the jack 11 is moved obliquely downward. Since the hydraulic hoses 121 and 131 are withdrawn to some extent, it is preferable to set a slack according to the drawing allowance and accommodate the slack portion in a separate chamber 18 provided adjacent to the casing 17.

  When the rod 19 with a bit is pulled out from the guide hole 8, a new rod 19 with a bit is mounted by the same reverse procedure. The bit body 10 may be detached from the rod 9 and only the bit body 10 may be replaced.

  Thus, it is not necessary for the worker to go out to the face side of the cutter head 2, and the used rod 19 with the bit or the bit body 10 can be replaced with a new one in the cutter chamber 5 on the anti-face face side. Since the worker does not come out on the face side of the cutter head 2, the ground improvement range can be significantly smaller than the type described in the above-mentioned document 2, and the cost can be reduced. Moreover, it is environmentally preferable that the construction time for ground improvement is shortened and the ground improvement range becomes small.

  In this way, the bit-attached rod 19 or the bit body 10 is replaced with a new one, and after the worker returns to the rear of the partition wall 7 through the manhole 72, the manhole cover 71 is attached again and the excavation is resumed. If the bit body 10 is worn out again due to excavation, as described above, the jack 11 can be pushed out to return the cutting radius of the bit body 10 to the pre-wearing state. By repeating the exchange from within the cutter chamber 5, it is possible to sufficiently cope with long-distance excavation.

It is a front view of the cutter head by which the attachment structure of the cutter bit which shows suitable embodiment of this invention was employ | adopted. It is the II-II sectional view taken on the line of FIG. It is the III-III sectional view taken on the line of FIG. It is explanatory drawing which shows 1 process of the effect | action of the said attachment structure, ie, the maintenance method of a cutter bit. It is explanatory drawing which shows the process following FIG.

Explanation of symbols

2 Cutter head 7 Bulkhead 8 Guide hole 9 Rod 10 Bit body 11 Jack 19 Rod with bit body attached (rod with bit)
30 Cutter bit 81 Opening edge X Length Y Distance

Claims (5)

A cutter bit mounting structure that is mounted on a cutter head that is rotationally driven with respect to the face,
A guide hole formed by communicating the face side and the anti-face side with the cutter head;
A rod slidably inserted into the guide hole;
A bit body attached to the end of the rod on the face side;
Cutter bit mounting, characterized in that it comprises a jack connected to the end of the rod on the side opposite to the face of the rod so that it can be connected and disconnected, and the other end pivotally supported on the part on the side of the cutter head opposite to the face Construction.   The cutter according to claim 1, wherein a length of the rod body attached to the rod is set to be shorter than a distance from an opening edge of the guide hole on the opposite face side to a partition wall arranged behind the cutter head. Bit mounting structure. The guide hole is formed on the outer peripheral side of the cutter head so as to incline radially outward from the anti-face side to the face side,
The cutter bit mounting structure according to claim 1 or 2, wherein the bit body cuts a cutting face substantially in front of an outer peripheral edge of the cutter head. A maintenance method for a cutter bit attached to a cutter head that is rotationally driven with respect to a face,
A guide hole formed by communicating the face side and the anti-face side with the cutter head;
A rod slidably inserted into the guide hole;
A bit body attached to the end of the rod on the face side;
A jack whose one end is connected to the end of the rod on the side opposite to the cutting edge so as to be detachable and the other end is pivotally supported on the portion on the side opposite to the cutting face of the cutter head;
When the bit body is worn by a predetermined amount, by extending the jack according to the wear amount, the protruding length from the guide hole at the tip of the worn bit body is returned to the state before wear,
When the wear of the bit body further progresses, the jack is contracted, and on the opposite face side of the cutter head, the jack is separated from the rod, the rod is pulled out from the guide hole, and the bit body is singly or A maintenance method of a cutter bit, wherein the rod is replaced integrally with the rod. A maintenance method for a cutter bit attached to a cutter head that is rotationally driven with respect to a face,
A guide hole formed by communicating the face side and the anti-face side with the cutter head;
A rod slidably inserted into the guide hole;
A bit body attached to the end of the rod on the face side;
A jack whose one end is connected to the end of the rod on the side opposite to the cutting edge so as to be detachable and the other end is pivotally supported on the portion on the side opposite to the cutting face of the cutter head;
When the bit body is worn by a predetermined amount, by extending the jack according to the wear amount, the protruding length from the guide hole at the tip of the worn bit body is returned to the state before wear,
When the wear of the bit body further progresses, the jack is contracted, the rod body is pulled out from the guide hole on the opposite face side of the cutter head, and the bit body is detached from the jack. A cutter bit maintenance method, wherein the cutter bit is replaced alone or integrally with the rod.

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