JP2007285027A - Auger screw holder device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an auger screw holder device capable of firmly holding an auger and drilling a hole at an accurate angle. <P>SOLUTION: The auger 1 supports a work platform 5 via a turntable 4 on a truck 2. A bracket 8 is projected from the front end of the work platform 5, and a guide leader 9 is erected on the front end of the bracket 8. An auger screw 12 and a rotary drive unit 13 of the auger screw 12 are supported on the guide leader 9 vertically movably. The bottom end of the auger screw 12 is secured to the auger screw holder 20 attached to a chassis 2a of the truck 2. The auger screw holder 20 is supported by a horizontal articulated arm 30 and an inclination variable supporting unit 50 attached to the tip of the arm 30. The articulated arm 30 and the inclination variable supporting unit 50 are actuated by a hydraulic cylinder. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an auger screw holder device for an auger (earth auger).

  When building foundation piles on the ground, in recent years, a pre-boring method is often used in which the foundation piles are pushed into holes that have been excavated in the ground beforehand. An auger is used to dig a hole in the ground. Since the screw of the auger is very long, a steady rest is provided at the lower end of the screw. Examples thereof can be seen in Patent Documents 1 and 2.

In the multi-axis auger described in Patent Document 1, a steady rest at the lower end of the auger screw is attached to the front surface of the leader bracket. In the arm type work machine described in Patent Document 2, a catch hawk for guiding an auger screw is extended from the work machine main body.
JP-A-7-247574 ([0018], FIGS. 1 and 2) JP-A-5-222888 ([0008] [0009], FIGS. 1-4)

  In recent years, the need for a foundation pile capable of supporting a heavy load has increased as the number of buildings has increased. The foundation pile for heavy loads inevitably has a large diameter, and the length becomes long in order to reliably reach the support layer in the ground. And in order to make the load bearing performance sufficient, it is not enough to simply lengthen the dimensions of the foundation pile, and it must be built vertically accurately.

It is necessary to guide the auger screw correctly in order to excavate a hole to build a long foundation pile accurately vertically. In this respect, the steady rest and catch hawk described in Patent Documents 1 and 2 have been difficult to say perfectly suited for the purpose. This is because they all extend from the part above the swivel of the work machine. There is always play in the swivel mechanism. The play in the rotation direction on the swivel base appears as a swing of the auger screw, and the magnitude of the swing A is obtained by
A = 2 × π × R × α / 360 ° R is a radius from the center of the swivel to the auger screw, and α is a play value in the rotation direction of the swivel. When R is 4,000 mm and α is 0.2 °, A is about 14 mm.

  The above-mentioned runout A inevitably occurs, and therefore the mechanisms disclosed in Patent Documents 1 and 2 cannot guarantee that the hole is accurately excavated vertically. Further, in an auger having a guide leader as described in Patent Document 1, the guide leader itself may be rotatable about a vertical axis, and the play in the rotation direction of the guide leader is the play in the rotation direction of the swivel base. The lower end position of the auger screw becomes increasingly unstable. In addition, the guide leader puts out the vertical in the stay, but the play of the stay mechanism also affects the instability of the lower end position of the auger screw.

  The present invention has been made in view of the above points, and an object thereof is to provide an auger screw holder device that can hold an auger screw without shaking and excavate a hole at an accurate angle.

  (1) In order to achieve the above object, the present invention is characterized in that an auger screw holder for positioning an auger screw is attached to a chassis of an auger carriage.

  According to this configuration, since the auger screw holder is attached to the chassis of the carriage, which is a part below the swivel base, it is not affected by the play of the swivel part. Since it is unlikely that the carriage will be displaced with respect to the ground, the auger screw holder reliably plays the role of positioning the lower end of the auger screw at a predetermined position.

  (2) In the auger screw holder device having the above-described configuration, the auger screw holder is supported by an articulated arm attached to the chassis, and the bent shape of the articulated arm is changed. It is characterized in that an actuator is provided.

  According to this configuration, the position of the auger screw holder relative to the carriage can be adjusted by changing the bent shape of the articulated arm with the actuator. For this reason, it is not necessary to move the carriage to adjust the position of the auger screw holder.

  (3) Further, in the auger screw holder device having the above-described configuration, the present invention is characterized in that the articulated arm is a horizontal articulated type.

  According to this configuration, since the articulated arm does not bend in the vertical direction, the auger screw holder can be maintained at a certain height from the ground regardless of whether the actuator is activated or deactivated.

  (4) According to the present invention, in the auger screw holder device configured as described above, the auger screw holder is supported by the articulated arm via a variable tilt support device, and the variable tilt support device includes an auger screw. An actuator for changing the vertical angle of the holder is provided.

  According to this configuration, since the angle of the auger screw holder in the vertical direction can be changed by the actuator, the angle of the auger screw can be corrected and the hole can be excavated at the correct angle.

  (5) Further, the present invention is characterized in that, in the auger screw holder device having the above-described configuration, the auger screw holder is capable of relative displacement in the vertical direction with respect to the articulated arm.

  According to this configuration, when the excavated soil accumulates inside the auger screw holder, the auger screw holder can be lifted and the excavated soil can be discharged out of the auger screw holder.

  According to the present invention, the lower end portion of the auger screw can be reliably positioned at a predetermined position by attaching the auger screw holder to the chassis of the auger carriage.

  One embodiment of the present invention is shown in FIGS. 1 is a side view of an auger, FIG. 2 is a horizontal sectional view of a guide leader, FIG. 3 is a plan view of an auger screw holder portion, and FIG. 4 is a perspective view of an auger screw holder variable tilt support device.

  The auger 1 has a carriage 2 having a caterpillar (or crawler) 3 as a moving means. The carriage 2 supports the work platform 5 via the turntable 4. The work platform 5 has a built-in power source such as an engine, a generator, a hydraulic pump, and a cabin 6 on which an operator gets on and operates. At the rear of the work platform 5, an outrigger 7 is provided that contacts the ground G with a wider front width than the caterpillar 3 and increases the stability of the auger 1. A bracket 8 protrudes from the front end of the work platform 5, and a guide leader 9 is erected at the tip thereof. An extendable stay 10 connects the upper portion of the guide leader 9 and the rear portion of the work platform 5. The stay 10 is provided in a pair of left and right like the auger described in Patent Document 1, and maintains the guide leader 9 vertically by adjusting the left and right extension.

  As shown in FIG. 2, the guide leader 9 is composed of a pipe having a circular cross section, and a pair of left and right guide rails 11 are attached to the front side surface. The guide rail 11 is also composed of a pipe having a circular cross section, and extends vertically over almost the entire length of the guide leader 9.

  The guide rail 11 supports the rotation drive device 13 of the auger screw 12. The rotation drive device 13 is connected to the guide reader 9 so as to be slidable in the vertical direction by an arm 14 that holds the left and right guide rails 11 from the outside and does not rotate in a horizontal plane. The weight of the rotary drive device 13 is fed from the upper end of the guide leader 9 and supported by a suspension cable 16 that is wound around a movable pulley 15 on the upper surface of the rotary drive device 13. If the amount of extension of the suspension cable 16 is increased, the rotation drive device 13 is lowered, and if the amount of extension of the suspension cable 16 is decreased, the rotation drive device 13 is raised. The auger screw 12 moves up and down together with the rotary drive device 13. A fixed guide 17 for guiding the auger screw 12 is attached in the middle of the guide rail 11.

  The lower end of the auger screw 12 is positioned by an auger screw holder 20 attached to the carriage 2. Hereinafter, the auger screw holder 20 and its support structure will be described.

  The auger screw holder 20 is a pipe-like member, and has an axial length and an inner diameter for receiving two or more spirals of the auger screw 12 with a predetermined gap. A support mount 21 is fixed to the side surface of the auger screw holder 20. The auger screw holder 20 is supported by an articulated arm 30 (see FIG. 3) and a variable tilt support device 50 (see FIG. 4) provided at the tip thereof.

  The multi-joint arm 30 is a horizontal multi-joint type, and the first arm portion 31, the second arm portion 32, and the third arm portion 33 are sequentially connected by joint portions so as to be able to turn only within a horizontal plane. The first arm portion 31 is connected to a bracket 34 fixed to the front center of the chassis 2a of the carriage 2 by a joint portion 35, and the second arm portion 32 is connected to the tip of the first arm portion 31 by a joint portion 36. The three arm part 33 is connected to the tip of the second arm part 32 by a joint part 37.

  The bent shape of the multi-joint arm 30 changes depending on the operation of the actuator. In this embodiment, a clevis type hydraulic cylinder is employed as the actuator.

  The chassis 2a and the first arm portion 31 are connected by a hydraulic cylinder 38, and the angle of the first arm portion 31 with respect to the chassis 2a is changed by the amount of expansion and contraction of the hydraulic cylinder 38, and the angle is fixed. The first arm part 31 and the second arm part 32 are connected by a hydraulic cylinder 39, the angle of the second arm part 32 with respect to the first arm part 31 is changed by the amount of expansion and contraction of the hydraulic cylinder 39, and the angle is fixed. The second arm portion 32 and the third arm portion 33 are connected by a hydraulic cylinder 40, and the angle of the third arm portion 33 with respect to the second arm 32 is changed by the amount of expansion and contraction of the hydraulic cylinder 40, and the angle is fixed. By controlling the amount of expansion / contraction of the hydraulic cylinders 38, 39, 40, the tip of the third arm portion 33 can be freely positioned within a predetermined two-dimensional movable region and fixed at that position.

  It is also possible to adopt a combination of an electric motor and a speed reducer as the actuator. The combination is arranged at each joint.

  A pole 41 is erected vertically on the upper surface of the distal end portion of the third arm portion 33. A base 51 of a variable tilt support device 50 is attached to the pole 41 so as to be movable up and down and not rotatable relative to the pole 41. The base 51 can be raised by a predetermined stroke until it hits the stopper 41 a at the upper end of the pole 41. The base 51 can be lifted by using a suspension cable 42 similar to the suspension cable 16, but can be lifted by another drive mechanism such as a hydraulic cylinder or a ball screw.

  A support shaft 52 projects horizontally from the side surface of the base 51. The support shaft 52 supports the intermediate support block 53. The intermediate support block 53 supports a support shaft 54 protruding from the support mount 21 of the auger screw holder 20. The support shaft 52 is fixed with respect to one of the base 51 and the intermediate support block 53 and is rotatable with respect to the other, and the support shaft 54 is fixed with respect to one of the support mount 21 and the intermediate support block 53 and with respect to the other. It is free to rotate. With this mechanism, the angle of the intermediate support block 53 is variable around the axis of the support shaft 52, and the angle of the support mount 21 is variable around the axis of the support shaft 54.

  The axis of the support shaft 52 and the axis of the support shaft 54 are orthogonal. By changing the angle θA of the intermediate support block 53 with respect to the base 51 and the angle θB of the support mount 21 with respect to the intermediate support block 53, the inclination of the auger screw holder 20, that is, the angle in the vertical direction can be adjusted in all directions. .

  The variable tilt support device 50 is provided with an actuator for changing the angle of the auger screw holder 12 in the vertical direction. A trunnion type hydraulic cylinder is used in this embodiment.

  A hydraulic cylinder 56 is attached to a fork 55a of a bracket 55 fixed to the base 51 so as to be tiltable. The hydraulic cylinder 56 is inclined in a plane perpendicular to the support shaft 52 with respect to the fork portion 55a. The rod of the hydraulic cylinder 56 is connected to a bracket 57 protruding from the intermediate support block 53.

  A hydraulic cylinder 59 is attached to a fork portion 58a of a bracket 58 fixed to the intermediate support block 53 so as to be tiltable. The hydraulic cylinder 59 is inclined in a plane perpendicular to the support shaft 54 with respect to the fork portion 58a. The rod of the hydraulic cylinder 58 is connected to a connecting shaft 60 protruding from the support mount 21.

  When the hydraulic cylinder 56 expands and contracts, the angle θA of the intermediate support block 53 with respect to the base 51 changes, and when the hydraulic cylinder 59 extends and contracts, the angle θB of the support mount 21 with respect to the intermediate support block 53 changes. That is, by controlling the amount of expansion / contraction of the hydraulic cylinders 56 and 59, the angle of the auger screw holder 20 in the vertical direction can be freely adjusted, and the angle can be fixed after the adjustment.

  When excavating the foundation pile built-in hole by the auger 1, the caterpillar 3 is driven to move the auger 1 to the excavation site and the auger screw 12 is positioned. The position of the auger screw holder 20 is accurately set by controlling the hydraulic cylinders 38, 39, and 40 to change the bent shape of the articulated arm 30, and the hydraulic cylinders 56 and 59 are controlled to control the axis of the auger screw holder 20. To be exactly vertical. Then, the stay 10 is expanded and contracted so that the axis of the guide leader 9 is accurately vertical. The base 51 of the variable tilt support device 50 is in the lowest position at this time, and the auger screw holder 20 is not so far away from the ground G.

  Thus, when the auger screw holder 20 and the guide leader 9 are made vertical and preparations for excavating a vertical hole are completed, the operation of the rotary drive device 13 is started. If the rotary drive device 13 is lowered while rotating the auger screw 12, a vertical hole is excavated in the ground G. The auger screw holder 20 holds the auger screw 12 during excavation. Since the auger screw holder 20 is attached to the chassis 2 a of the carriage 2, the auger screw holder 20 is not affected by the play of the turning portion 4. Since it is unlikely that the carriage 2 will be displaced with respect to the ground G, the auger screw holder 20 reliably positions the auger screw 12 at a predetermined position.

  When excavated soil has accumulated in the auger screw holder 20, the base 51 of the variable tilt support device 50 is pulled up to widen the gap between the lower end of the auger screw holder 20 and the ground G. After the excavated soil is discharged out of the auger screw holder 20, the auger screw holder 20 is lowered again to continue excavation.

  When a vertical hole having a predetermined depth has been excavated, the auger screw 12 is pulled up, and the foundation pile is built using the auger 1 or using a machine different from the auger 1.

  Although the embodiments of the present invention have been described above, various modifications can be made without departing from the spirit of the invention.

  The present invention is widely applicable to an auger that excavates a vertical hole with a screw.

Auger side view Horizontal section of guide reader Top view of the auger screw holder Perspective view of a variable tilting support device for auger screw holder

Explanation of symbols

G ground 1 auger 2 cart 2a chassis 4 swivel 5 work platform 9 guide reader 12 auger screw 13 rotary drive device 20 auger screw holder 30 articulated arm 38, 39, 40 hydraulic cylinder (actuator)
50 Tilt variable support device 56, 59 Hydraulic cylinder (actuator)

Claims (5)

  An auger screw holder device characterized in that an auger screw holder for positioning an auger screw is attached to a chassis of an auger cart. The auger screw holder is supported by an articulated arm attached to the chassis, and the articulated arm is provided with an actuator for changing a bent shape thereof. Auger screw holder device.   The auger screw holder device according to claim 2, wherein the multi-joint arm is of a horizontal multi-joint type.   The auger screw holder is supported by the articulated arm via a variable tilt support device, and the variable tilt support device is provided with an actuator that changes the vertical angle of the auger screw holder. The auger screw holder device according to claim 2 or 3, characterized by the above.   The auger screw holder device according to any one of claims 2 to 4, wherein the auger screw holder is capable of relative displacement in the vertical direction with respect to the articulated arm.

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