JP4542917B2 - Double pipe type pipe cutting device - Google Patents

Description

  The present invention relates to a double-pipe type pipe cutting device, and more particularly to a device that can be easily repaired and replaced when a drilling cutter or bit is damaged or worn.

  For example, when laying pipes such as water and sewage pipes in the ground, instead of the conventional open-cut method, there is a tendency to adopt a pipe propulsion method in which pipes are laid in the ground, and lay small diameter pipes. In such a case, a double pipe type pipe cutting device is employed (Patent Document 1).

  In this double-pipe type pipe milling device, the propulsion unit body is slidably mounted on the slide base and a propulsion jack is provided. The propulsion unit is advanced by the propulsion jack, and the propulsion unit (steel pipe) is attached to the propulsion unit main unit. The casing rod (inner pipe) is rotatably incorporated in the propulsion pipe, the excavation cutter is provided at the tip of the casing rod, the casing rod is rotated by the drive motor, and the front is excavated by the excavation cutter. , Pull out the casing rod, set the vinyl chloride pipe etc. in the propulsion pipe, insert the filler etc. between the propulsion pipe and the vinyl chloride pipe etc., thus laying the double structure pipe ing.

  By the way, the excavation cutter used in the pipe cutting device has a structure in which a large number of bits, for example, roller bits, are attached to the cutter head (Patent Document 2 and Patent Document 3). For propulsion, it is desirable to provide a bit so that it can be excavated with a diameter larger than that of the propulsion pipe.

  On the other hand, excavation cutters and bits may be damaged and worn during excavation of bedrock. In the case of a large-diameter pipe turning device, an operator can enter the propulsion pipe and change excavation cutters and bits, or can be automatically changed by a machine (Patent Document 4, Patent Document 5). In the case of a double pipe system for propelling the pipe, it is difficult for the operator to perform the exchange work or the automatic exchange by the machine.

JP 2003-239865 A JP 2001-65291 A JP 2001-323780 A JP 2001-65291 A JP 2000-291384 A JP 2001-27097 A

  In view of such problems, an object of the present invention is to provide a double-pipe type pipe advancing device that can be easily repaired and replaced when a drilling cutter or a bit is damaged or worn.

  Therefore, the double-pipe type pipe drilling device according to the present invention includes a casing rod having an excavating cutter at the tip thereof, which is rotatably incorporated in the propelling pipe, and the casing rod is rotated to excavate forward sediments by the excavating cutter. In the double-pipe type pipe drilling device configured to propel the propulsion pipe, a roller bit is attached to the cutter head of the excavation cutter so as to be rotatable around a rotary shaft, and the rotary shaft is connected to the roller The roller bit is provided at an eccentric position from the center of the flat shape of the bit, and the roller bit receives the pressure during excavation and rotates around the rotation shaft, and its radially outer end is located inside the inner surface of the propulsion pipe. The inner position located on the outer side and the radially outer end are displaced between a position equal to the outer surface of the propelling pipe or an outer position located further outward than this. That.

  One of the features of the present invention is that the rotation shaft is provided at a position eccentric from the center of the planar shape of the roller bit.

  As a result, during excavation, the radially outer end of the roller bit is displaced between a position equal to the outer surface of the propulsion pipe or an outer position and an inner position of the inner surface of the propulsion pipe. It is possible to excavate to a larger diameter, and the propulsion work can be performed smoothly.

  Also, when the excavation cutter or roller bit is damaged and worn, if the radially outer end of the roller bit is positioned inward of the inner surface of the propulsion tube, the casing rod is pulled backward from the propulsion tube, and the excavation cutter or roller bit is removed. Can be repaired or replaced.

  The double pipe type pipe cutting device according to the present invention has a great effect when applied to laying water and sewage pipes in the horizontal direction, but similarly when driving steel pipe piles and the like into the ground in the vertical direction. Applicable. In this case, the pipe can be configured as a double-structure pipe as described above, or can be left as a single structure like a steel pipe pile. Further, the method of propelling the pipe is not limited to the method described in the above-mentioned Patent Document 1, that is, the method of propelling the propulsion device main body by the propulsion jack, but other methods, for example, the method of directly propelling the propulsion pipe with the propulsion jack are adopted. You can also

  The rotation axis of the roller bit may be provided parallel to the center axis of the cutter head. However, if the roller bit is inclined with respect to the center axis of the cutter head, when the casing rod is pulled into the propulsion pipe, the roller bit is moved to the propulsion pipe. Since the outer end in the radial direction hits the tip of the shaft and rotates so as to be inward of the inner surface of the propelling pipe, the excavation cutter and the roller bit can be repaired and replaced more easily.

  Hereinafter, the present invention will be described in detail based on specific examples shown in the drawings. 1 to 4 show a preferred embodiment of a double pipe type pipe cutting device according to the present invention. In the tube advancing device 10, a propulsion device main body 110 is mounted on a slide base 100 so as to be slidable in the front-rear direction. The propulsion device main body 110 is driven forward by the propulsion jack 150 and moved backward. It is like that.

  The propulsion device main body 110 is provided with a drive motor 111 and a spindle rod (not shown). A gear transmission mechanism is provided between the spindle rod and the drive motor 111. The spindle rod The base part of the casing rod 120 is attached to this.

  Further, a pusher 112 is attached to the propulsion unit main body 110, and a base portion of the propulsion pipe 130 is fitted into the pusher 112. A casing rod 120 is incorporated in the propelling tube 130, and a roller bearing (not shown) extending in the circumferential direction is interposed between the two so as to ensure smooth rotation and straightness of the casing rod 120. It has become.

  An excavation cutter 20 is attached to the tip of the casing rod 120. In this excavation cutter 20, the cutter head 200 has a ring shape, the mounting bracket 210 is fixed to the cutter head 200, the mounting bracket 210 is provided with an inclined mounting portion, and the rotating shaft 220 is provided on the mounting portion. The roller bit 230 is rotatably attached to the rotary shaft 220 by a bearing 221.

  The roller bit 230 has a structure in which a large number of cutting edges 232 are fixed to the outer surface of a cone 231 having a substantially truncated cone shape (may be elliptical or spherical) (however, only the outer shape of the cone 231 is shown in FIG. 4). The central axis a of the rotating shaft 220 is decentered from the central axis b of the roller bit 230 in a planar shape (a shape when the roller bit 230 is placed on a plane), and the radially outer end of the roller bit 230 is the inner surface of the propelling tube 130. Further, the position is displaced between an inner position located on the inner side and an outer position located on the same position as (or on the outer side of) the outer surface of the propelling tube 130.

  For example, when laying a pipe, a start shaft and a reach shaft are excavated, the propulsion device main body 110 and the slide base 100 are installed in the start vertical shaft, and the base of the propulsion tube 130 is attached to the pusher of the propulsion device main body 110 for propulsion. The casing rod 120 is incorporated in the tube 130, the base of the casing rod 120 is attached to the spindle rod, the drive motor 111 is driven to rotate the casing rod 120 in a predetermined direction, and the propulsion jack 150 is advanced by the propulsion jack 150. To drive.

  Then, the roller bit 230 of the excavating cutter 20 rotates around the rotating shaft 220 while revolving around the central axis of the cutter head 200, and excavates forward earth and sand such as earth and sand.

  At this time, since the central axis a of the rotating shaft 220 is eccentric with respect to the central axis b of the roller bit 230, the outer end in the radial direction of the roller bit 230 protrudes outward with respect to the outer surface of the propulsion pipe 130. Can be excavated to a diameter larger than the outer diameter of the propulsion pipe 130, and the propulsion pipe 130 can be lightened. And can be promoted smoothly.

  When the cutting edge 232 of the roller bit 230 is damaged or worn, the excavation cutter 20 is retracted into the propelling tube 130 while rotating in the reverse direction (or rotating). Then, the roller bit 230 hits the leading edge of the propelling tube 230, and the roller bit 230 escapes the leading edge of the propelling tube 230 with the reverse rotation of the excavating cutter 20, that is, inward of the inner surface of the propelling tube 130. Since it rotates around the rotation shaft 220 toward the inward position and the radially outer end of the roller bit 230 is kept inward from the inner surface of the propulsion pipe 130, the propulsion pipe 130 and the casing rod 120 are maintained. Is pulled back, the casing rod 120 can be pulled back while leaving the propelling tube 130 in the soil, so that the roller bit 320 can be repaired and replaced.

  Even when the excavation cutter 20 is damaged or worn, it can be repaired and replaced in the same manner as described above.

  Thereafter, when the casing rod 120 is returned into the propulsion pipe 130, the propulsion work can be performed in the same manner as described above.

  5 to 7 show a second embodiment, in which the same reference numerals as those in FIGS. 1 to 4 denote the same or corresponding parts. This example is an example of an excavation cutter suitable for use when cutting a large-diameter propulsion pipe. The rotary roller bit 230 of the excavation cutter 20 has a radially outer end that is more than the inner surface of the propulsion pipe 130. It is provided so as to be displaced between an inner position positioned inward and an outer position A positioned outward from the outer surface of the propelling tube 130.

  In addition, three fixed roller bits 240 are attached to the center of the excavating cutter 20 so as to incline and rotate around the rotation shaft 241. The rotation shaft 241 is a flat shape of the roller bit 240 (the plate is placed on a flat surface). Is coincident with the central axis.

1 is an overall schematic perspective view showing a preferred embodiment of a double pipe type pipe cutting device according to the present invention. It is a schematic side block diagram which shows the said embodiment. It is a block diagram which shows the attachment structure of the excavation cutter in the said embodiment. It is a figure for demonstrating the motion of the roller bit in the said embodiment. It is a front lineblock diagram showing the excavation cutter in a 2nd embodiment. It is a side block diagram which shows the structure of the excavation cutter in the said embodiment. It is a figure which shows the rotary roller bit in the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Slide base 110 Propulsion machine main body 120 Casing rod 130 Propulsion pipe 20 Excavation cutter 200 Cutter head 220 Rotating shaft 230 Roller bit 231 Cone 232 Cutting blade

Claims (1)

A double-pipe type pipe in which a casing rod having an excavation cutter at the tip is rotatably incorporated in the propulsion pipe, the casing rod is rotated, and the propulsion pipe is propelled while excavating forward sediments by the excavation cutter. In the cutting device,
The ring-shaped cutter head of the drilling cutter plurality of rollers bit is rotatably mounted around a rotation axis, the central axis of the cutter head to the position the rotating shaft is eccentric from the center of the planar shape of the roller bit Is inclined with respect to
The roller bit receives the pressure of earth and sand during excavation and rotates around the rotation shaft, and the radially outer end of the roller bit is located inward of the inner surface of the propulsion pipe and the radially outer end is propelled A double tube type pipe cutting device characterized by being displaced between a position equal to or more outward than the outer surface of the pipe.

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