JP2008008096A - Auger screw - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To push a part of discharged soil generated by excavation to the wall of an excavated hole and pressure-compact it and also to suppress the amount of the discharged soil. <P>SOLUTION: A plurality of compaction rollers 6 are horizontally rotatably attached to a screw blade 5 at equal intervals in the circumferential direction thereof for one pitch of the screw blade 5. The plurality of the compaction rollers 6 are so arranged that the outer peripheral surface 6a of each compaction roller is displaced inside the outer peripheral edge 5' of the screw blade 5. The shaft center of each support shaft 7 is arranged in parallel with the shaft center of a screw shaft 4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an auger screw that can suppress the amount of discharged residual soil during excavation.

  Conventionally, excavation is performed using a multi-axis auger screw in which a plurality of shafts are arranged in parallel in a construction for constructing a continuous retaining wall in the ground. In such construction, it is necessary to dispose of the soil generated during excavation. By the way, in order to promote excavation in this excavation work, excavation is performed while injecting cement milk or the like through the screw shaft, so that the injected cement milk is mixed in the discharged soil. For this reason, it cannot be used as backfilling soil, and the discharged soil becomes industrial waste, so that a lot of costs are generated for the treatment.

  Under such circumstances, it is required to reduce the amount of the discharged soil. As a means to remedy such problems, without discharging all the earth and sand excavated during excavation to the ground, a part of it is pressed against the excavated hole wall to reduce the amount of discharged soil and consolidate the hole wall An attempt to obtain the effect of preventing the hole wall from collapsing is disclosed in Patent Document 1. In this excavated soil compacted auger screw, as shown in FIGS. 3A and 3B, the upper screw blade 101 b extends along the rod 102 from the upper surface of the lower screw blade 101 a in one pitch of the screw blade 101. A trowel portion 103 having a curved pressing surface 104 projecting outward to the outer peripheral edge position of the screw blade 101 is provided on the lower surface of the screw blade 101, and scraped by the screw blade 101 when excavating with the auger screw. A part or most of the soil to be deepened is pressed against the hole wall surface to be compacted, and the amount of soil to be discharged is reduced. The back surface 105 of the iron part 103 in the direction of lifting the soil is formed flat.

JP 7-305587 A

  However, since the auger screw according to the prior art is provided with a piece called the iron part 103 in the middle between the screw blades 101, when the discharged soil generated by excavation is sequentially swept up by the screw blades 101, The movement is blocked by the iron part 103 and ideally pressed against the hole wall excavated by the curved pressing surface 104 of the iron part 103 to be in a consolidated state, but depending on the soil to be excavated, the iron part 103 However, it is not always compacted to the hole wall. Naturally, a large load accompanying this consolidation operation acts on the rod 102. Moreover, since this large side pressure partially acts on the screw shaft (rod 102) from one side, an acting force that pushes and bends the rod 102 from the lateral direction acts, and an irregular load is applied. The rod 102 is required to be more robust. Of course, the auger drive device is also required to have more power than necessary, and there is a problem that the equipment cost and the running cost due to operation increase.

  Note that Patent Document 1 also discloses that the iron part 103 has a half height in the vertical direction (indicated by a two-dot chain line a in FIG. 3). Alternatively, it is also described that a space portion is formed by notching a part of the screw blade 101 at a position in the rotation direction of the portion where the iron portion 103 is provided (not shown). With such a structure, it is possible to reduce the load force that acts on the rod 102 because a part of the soil that has been scraped passes through the gap or falls from the space portion, but on the other hand, On the other hand, there is a problem that the consolidation operation is remarkably lowered and the effect of suppressing the amount of discharged soil becomes insufficient.

  The present invention solves such problems and provides an auger screw that makes it easy to suppress the amount of discharged soil while pressing a part of the discharged soil generated by excavation into the hole wall for consolidation. It is intended to do.

In order to achieve the above object, an auger screw according to the present invention comprises:
In one pitch of the screw blades, a plurality of compacting rollers are provided so as to be equally divided in the circumferential direction of the screw blades so as to be horizontally rotatable (first invention).

  In the present invention, a plurality of rolling rollers disposed in the circumferential direction of the screw blades are grouped, and the group of rolling rollers is provided at a plurality of locations in the axial direction at appropriate intervals in the main points of the screw. (2nd invention).

  In the first invention or the second invention, it is preferable that the rolling roller is arranged such that the outer peripheral surface thereof is within the outer peripheral edge of the screw blade (third invention). Further, it is preferable that the rolling roller has a support shaft centered parallel to the screw shaft center (fourth invention). And it is good for the said rolling roller to be provided so that the support shaft can be attached or detached with respect to the said screw blade | wing (5th invention).

  According to the present invention, the discharge soil generated by excavation by the auger screw is raked up by the rolling roller disposed equally in the circumferential direction of the screw blade between the pitches of the screw blades of the auger screw. When the rolling roller arrangement position is reached, the discharged soil comes into contact with the rolling roller and is pushed outward. Since the rolling roller is rotatably provided, the discharged soil that is freely rotated and pushed in accordance with the rotation of the screw blades is pressed against the wall surface side of the excavation hole. Accordingly, the discharged discharged soil is pressed by the rolling roller, and the wall surface of the excavation hole is consolidated. Accordingly, a part of the discharged soil is pushed back to the excavation hole wall and the amount of discharged soil discharged to the ground part is suppressed. At the same time, the wall surface of the excavation hole is consolidated and the fall prevention effect is enhanced. Also, since the rolling rollers for the screw are divided into a plurality of equal parts per pitch and are free of rotation, even if there is a large amount of discharged soil, the entire amount of the discharged soil in the moving part is forcibly removed. Part of the screw shaft can be moved upward without being pushed out, so that it can be rotated without applying an excessive load to the screw shaft body, and an increase in driving force is suppressed to reduce running cost due to operation. There is an advantage that it can be prevented from becoming excessive.

  In addition, according to the present invention, since the rolling roller is detachably attached to the screw blade, the rolling roller is moved to a position where the wall consolidation effect of the drilling hole can be made effective during excavation according to the soil distribution of the drilling ground. The pressure rollers can be rearranged and used as a group. Therefore, even when the driving load of the auger screw becomes larger than that at the normal time, the digging hole wall is cured accordingly, and the workability can be improved. In addition, since the rolling roller is disposed in the rotation region of the screw blade, there is no hindrance to excavation propulsion, and the rolling roller can follow without receiving a large thrust, so that durability is not impaired. Moreover, since the rolling roller is detachably provided, there is an advantage that it can be used by replacing it with a new one even if it is worn out.

  Next, specific embodiments of the auger screw according to the present invention will be described with reference to the drawings.

  FIG. 1 shows a front view of an embodiment in which an auger screw according to the present invention is applied to a multiaxial auger. FIG. 2 shows a front view (a) of the main part of the auger screw according to the present embodiment, a sectional view (b) of the mounting portion of the rolling roller, and a plan view (c) showing the arrangement of the rolling roller.

  The auger screw 1 of this embodiment is applied to a triaxial auger, and the distal ends of both outer auger screws 1A and 1B are formed longer than the central auger screw 1C, and the excavating blades are formed at the distal ends. A cutter screw 3 with 2 is attached. Further, each auger screw 1 (each auger screw is generically represented by reference numeral 1. The same shall apply hereinafter) is provided with intermittently attached screw blades 5 in the axial direction with respect to the screw shaft 4 (rod). ing. The rod 4 has a required length and can be sequentially connected by a known joint structure (not shown).

  As shown in FIGS. 2A to 2C, the rolling roller 6 is divided into three equal parts in the circumferential direction at one pitch of the screw blades 5 at appropriate positions of the screw blades 5 provided intermittently. Individually arranged. Further, the lead of the screw blade 5 at the place where the rolling roller 6 is arranged is not particularly limited, but is set to ½ of the lead of the screw blade 5 at the place where the rolling roller 6 is not arranged. In addition, this setting is to shorten the support interval of the rolling roller 6 to reduce the pressing load that acts and to reduce the size, and to enhance the effect of pushing back the discharged soil to the wall surface of the excavation hole.

  The rolling roller 6 is made of steel, and is arranged between the upper screw blade 5a and the lower screw blade 5b in parallel to the axis of the rod 4 (screw shaft). The support shaft 7 is supported in a freely rotatable state. The support shaft 7 has, for example, a head portion 7a at one end, a thread portion 7b formed at the other end, and is inserted into shaft insertion holes 8, 8 'provided in the upper and lower screw blades 5a, 5b. At 7b, the nut 9 is fastened and fixed. The nut 9 is preferably prevented from coming off by means of, for example, a knock pin or idling (washing with a claw). The rolling roller 6 is provided so that its outer peripheral surface 6 a does not protrude from the outer edge 5 ′ of the screw blade 5 while being supported by the support shaft 7. By doing so, the auger screw 1 is placed within the rotation region of the screw blades 5 so as not to receive direct thrust when the auger screw 1 is dug. Further, the diameter of the rolling roller 6 is such that an appropriate gap t is formed between the support shaft 7 and the outer periphery of the rod 4 at the support position.

  As shown in FIG. 1, the rolling roller 6 formed in this way is divided into three groups equally divided in the circumferential direction, and, as illustrated in FIG. 1, a plurality of screw blades 5 are arranged at required positions in the axial direction. Installed and used. The number of groups of the rolling roller 6 is not limited to three, and may be two or three or more.

  According to the auger screw 1 of the present embodiment configured as described above, when excavation is performed by being driven by an auger drive device (not shown), the earth and sand excavated by the excavating blade 2 and the cutter screw 3 at the tip end are excavated. At the same time, when reaching the position of the screw blade 5 including the rolling roller 6 group in the middle of being scraped by the screw blade 5, the discharged soil moving along the lead of the screw blade 5 is blocked by the rolling roller 6.

  A part of the discharged soil whose movement is blocked by the rolling roller 6 is pushed outward by the rotation of the auger screw 1 or moves upward through the gap t between the rolling roller 6 and the rod 4. The discharged soil pushed outward by the rolling roller 6 is supported while the rolling roller 6 is rotatably supported, so that it is pressed while rolling toward the wall surface of the excavation hole as the screw blade 5 rotates. (Rolling). Therefore, the discharged soil sequentially pushed out toward the wall surface of the excavation hole is pressed by the respective rolling rollers 6 so that the wall surface of the excavation hole is in a consolidated state.

  A part of the discharged soil thus scraped is sequentially pushed out by the rolling roller 6 group toward the wall surface of the excavation hole, and is pressed back into the formation by the rolling roller group 6 provided in a plurality of stages. Therefore, it is lifted up without being pushed back, and the amount of discharged soil to the ground is reduced. Therefore, since a drilling aid such as cement milk is used for excavation, the disposal amount of soil discharged (industrial waste) discharged by mixing the drilling aid such as cement milk can be reduced.

  Further, as described above, the excavated discharged soil is pushed back to the formation in the middle of the excavation hole and is pushed into the excavation hole wall surface by the rolling roller 6, so that the circumference of the excavation hole is consolidated by the pressing. As a result, the strength is increased. Therefore, it is possible to prevent the wall surface from collapsing during excavation, to reduce the contact resistance between the screw blade 5 and the hole wall surface during excavation, and to obtain an effect of preventing an increase in load.

  In addition, in the location of the screw blade 5 provided with the group of roller compactors 6, all the discharged soil scraped up along the lead of the screw blade 5 is not blocked by the roller compactor 6, and as described above, the roller compactor 6. Since a part of the rod 4 is moved through the gap t between the rod 4 and the rod 4, the rod 4 can be smoothly rotated without being subjected to an excessive load and excavated. Moreover, since the free rotation is not hindered by the pressure resistance due to the discharged soil that also blocks the rolling roller 6, it can roll with the rotation of the screw blades 5 to roll the earth and sand pushed outward. It is.

  Further, since the auger screw 1 is excavated by rotating it forward and backward during operation, even if a situation occurs in which the discharged soil is prevented from moving in the rolling roller 6 group, the auger screw 1 is pushed back by the reverse operation. And discharge without stagnation.

  In this embodiment, since the rolling roller 6 is detachably provided, when there is a soft layer in a part of the formation, the auger screw serving as the excavation depth corresponding position corresponding to the soft layer. If a rolling roller 6 attached to a roller 4 of a screw blade 5 provided in advance on one rod 4 is used or a new rolling roller 6 is attached and excavated and propelled in the manner described above, excavation in the soft stratum It is possible to finish the formation around the excavation hole into a compacted state by pushing the discharged soil into the hole wall.

  In the above description, the rolling roller provided between the screw blades has been described as being provided with the axis of the support shaft parallel to the axis of the rod. It is also possible to attach a support shaft with an axis perpendicular to the helix angle and to support the rolling roller rotatably with this support shaft (not shown). Also in this case, it is preferable that the circumferential surface of the rolling roller is disposed so as to be inside the outer edge of the screw blade. Even if comprised in this way, there exists an effect similar to the said embodiment.

  In the description of the above embodiment, a triaxial auger screw is described. However, the present invention can be applied to a uniaxial auger screw as it is.

1 is a front view of an embodiment in which an auger screw according to the present invention is applied to a multiaxial auger. Front view (a) of the main part of the auger screw of the present embodiment, a sectional view (b) of the mounting part of the compaction roller, and a plan view (c) showing the arrangement of the compaction roller Partial side view (a) and plane sectional view (b) of an auger screw having a known excavated soil compaction function

Explanation of symbols

1 auger screw 2 drilling blade 4 rod (screw shaft)
5 Screw blade 6 Rolling roller 7 Support shaft

Claims (5)

  An auger screw characterized in that a plurality of compacting rollers are attached to be freely rotatable in a circumferential direction between the pitches of the screw blades equally in the circumferential direction of the screw blades.   2. A group of a plurality of roller compactors arranged in the circumferential direction of the screw blades, and the group of roller compactors are provided at essential locations of the screw at a plurality of locations in the axial direction at appropriate intervals. Auger screw as described in.   The auger screw according to claim 1, wherein each of the rolling rollers is disposed such that an outer peripheral surface thereof is within an outer peripheral edge of the screw blade.   The auger screw according to any one of claims 1 to 3, wherein a support axis of the rolling roller is arranged in parallel with the screw axis.   The auger screw according to any one of claims 1 to 4, wherein a support shaft of the rolling roller is detachably attached to the screw blade.

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