JPH10110449A - Excavator and excavation construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discharge each discharged by an auger screw smoothly to an upper section by forming the diameter of the shaft joining section of the auger screw constituted of a plurality of separable and connectable split shafts in approximately the same size as the front-rear shafts of the joining section. SOLUTION: The joining sections 6 of an auger screw 10 consist of a female screw 14 bored onto the same axial center from the end face side of one split shaft 7a and a male screw 12 bored on the end face side of the other split shaft 7b while axial centers are equalized. The diameter of the male screw 12 is made smaller than the shaft diameter of the split shaft 7b, and a shaft diameter in the joining sections of the female screw 14 is made approximately the same as the shaft diameter of the split shaft 7a. Screws directed in the same directions as screws 8 are threaded to the male screw 12 and the female screw 14, and the screws of the joining secions 6 are not loosened by the rotational resistance of the auger screw 10. The catching of excavated soil in the joining sections is prevented by forming the diameters of the joining sections 6 the same as the diameter of a shaft 7. Accordingly, trouble such as the stop of the auger screw 10 due to the biting of stone and gravel between a casing and the auger screw 10 in pile installation by inner excavation is avoided, and excavation using the casing is ensured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavator for drilling in the ground such as an earth auger used for foundation work such as a hollow excavation method, a cast-in-place pile method, a pre-boring method, and an underground continuous wall method. The present invention relates to a drilling method using a drilling device.

[0002]

2. Description of the Related Art An excavator equipped with an auger screw has been proposed in which the auger screw can be divided into a plurality. For example, assuming that the auger screw is made divisible, as shown in FIG. 5, a male joint part having a square tenon 53a having substantially the same diameter as the shaft 53 protrudes from one end of the divided auger screws 51, 52. 55, and at the other end, a mortise 56
a provided with a female joint portion 56 formed with a.

[0003]

However, in the above-mentioned splittable auger screw 50, since the joint portions 55 and 56 are thicker than the front and rear shaft diameters, there are the following problems. . For example, in the case of the middle digging method of a steel pipe pile, as shown in FIG.
9 removes stones, rocks, etc. along the axis 53 by the rotation of 9
Are raised to discharge the discharged soil 63 to the ground surface. However, the discharged soil 63 is caught by the joints 55 and 56 which are thicker than the shaft, and hinders smooth discharge of the discharged soil. . Further, there is a problem that a stone or a wrench bites between the casing 60 and the auger screw 50, and the auger screw 50 stops or the rotation resistance of the auger screw 50 becomes extremely high.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. In an excavating apparatus and an excavation method using a separable auger screw, the auger screw can smoothly lift and discharge the soil, and stone clogging can be achieved. An object of the present invention is to provide an excavation apparatus and an excavation method that can surely perform excavation using a casing such as a middle excavation method on hard ground or the like that is unlikely to occur and has a large stone diameter.

[0005]

According to a first aspect of the present invention, there is provided an excavator having an auger screw comprising a shaft and a screw provided around the shaft, the excavator being used for drilling a ground. An apparatus, wherein the shaft of the auger screw is composed of a plurality of divided shafts that can be separated and joined, and a joint for joining these divided shafts is formed to have substantially the same diameter as the front and rear axes of the joint. And

According to the first aspect of the present invention, since the shaft of the auger screw can be separated and connected,
As before, the auger screw can be split during transport,
In addition, handling becomes easy when the auger screw is set up or put down. Furthermore, when the auger screw is inserted into the ground while rotating, and a perforation is provided in the ground, the joint portion of the auger screw has substantially the same diameter as the front and rear axes of the joint portion. Excavated soil such as stones and rubble that rises and is discharged to the surface of the ground does not get caught at the joint, so that the excavated earth is smoothly discharged.
Accordingly, an increase in the rotational resistance of the auger screw due to the catching of the earth at the joint is prevented, and the load on the motor for rotating the auger screw and the driving device for insertion can be reduced. In particular, when used in the method of passing auger screws through the casing and drilling in the ground, such as the middle boring method, stones and wrench bite between the casing and the auger screw, and the auger screw stops. Since problems such as curling and extremely high rotational resistance are avoided, excavation using a casing such as a middle excavation method can be reliably performed even on a hard ground having a large stone diameter.

According to a second aspect of the present invention, there is provided an excavating method using the excavating apparatus according to the first aspect, wherein the divided shafts are joined to assemble an auger screw and inserted into the ground while rotating the auger screw. Then, the soil was lifted and discharged along the axis by the rotation of the screw, and a perforation was provided in the ground.

[0008] According to the excavation method of the second aspect, based on the operation and effect of the first aspect, the auger screw can smoothly lift and discharge the soil, and hardly causes stone clogging. Excavation using a casing such as the middle boring method can be reliably performed even on a large hard ground or the like.

The excavation method according to the present invention is not limited to a method of forming a hole in the ground using an auger screw, such as a hollow excavation method, a cast-in-place pile method, a pre-boring method, and an underground continuous wall method. Although the same effect can be obtained even when used in a simple construction method, it is more effective in a construction method in which an auger screw rotates in a casing to raise the earth removal, such as a middle boring method.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. [First Embodiment] FIG. 1 is a schematic diagram showing a state in which an excavator (earth auger) 1 according to a first embodiment of the present invention is used in a middle boring method. The excavator (earth auger) 1 includes a crane 3, a driving device 4, an auger screw 10, and the like. The auger screw 10 is suspended by the crane 3, and is moved in the vertical direction while being rotated by the driving device 4, so that the ground Drilling is performed while drilling. The auger screw 10 is provided with a spiral screw 8 around a shaft 7 and an auger head 9 for excavating the ground at the tip. The auger screw 10 can be divided into a plurality of pieces in order to simplify transportation and facilitate handling when the auger screw 10 is set up or laid down. That is, the division shafts 7a, 7b,.
6 to form a single auger screw 10. And, as shown below, the joints 6 and 6 are formed with the same shaft diameter as the shafts 7 before and after the joints, so that the excavated soil can be smoothly discharged and discharged.

FIG. 2 is a side view showing a joint portion of the auger screw 10. The joint 6 of the auger screw 10 is configured by providing a female screw 14 on one split shaft 7a and a male screw 12 on the other split shaft 7b. Male screw 1
Reference numeral 2 denotes a shaft having the same axial center protruding from the end face side of the divided shaft 7b, and has a smaller diameter than the shaft diameter of the divided shaft 7b.
The female screw 14 is formed on the same axis from the end face side of the split shaft 7a, and the joint portion 6 has the same shaft diameter as the split shaft 7a. The male screw 12 and the female screw 14 are cut in the same direction as the screw 8, and when drilling the ground while rotating the auger screw 10, the screw of the joint 6 is loosened due to rotational resistance. Not to be. In the present embodiment, as an excavation method using the above-described excavator 1, an example in which a ground is drilled by a middle excavation method will be described. In the middle boring method, an auger screw 40 is built in a hollow portion of a casing 40 such as a tubular concrete pile or a steel pipe pile, and the auger screw 40 excavates the ground at the tip of the casing 40 to a predetermined depth while excavating the ground. Is a construction method that penetrates
This method can be performed with low noise and low vibration.

Excavated soil excavated by the auger screw 40 (stone, wrench, earth removal, etc.) rises in the casing 40 along the shaft 7 by the rotation of the screw 8, and is discharged from the upper end of the casing 40 to the ground surface. In the case where the joint is formed larger than the shaft diameter of the auger screw as in the past, excavated soil such as stones that have risen along the axis is caught at the joint, and bites between the casing and the auger screw, In some cases, the rotation of the auger screw stops or the rotation resistance becomes extremely large. However, in this excavator 10, the joint 6 is formed to have the same diameter as the shaft 7 as described above. Excavated soil rises smoothly,
The above conventional problems are avoided. Although not shown, the casing 40 is laid down by its own weight of equipment attached to the casing 40 or by a combination of its own weight and press-fitting or tapping. As described above, according to the excavator 1 and the excavation method shown in this embodiment, since the joint 6 of the auger screw 10 has substantially the same diameter as the shaft 7 before and after the joint, When drilling holes in the ground, the excavated soil, such as stones and rubble, which rises along the axis 7 of the auger screw 10 and is discharged to the surface of the ground, is not caught by the joint 6 and the excavated earth is smoothly discharged. Can be done. Therefore,
An increase in the rotational resistance of the auger screw 10 due to the removal of soil at the joint can be prevented, and the load on the drive unit 4 for rotating the auger screw 10 or inserting it into the ground can be reduced. In particular, when used in a construction method in which the auger screw 10 is passed through the casing 40 and a perforation is made in the ground, such as the inner boring method shown in this embodiment, a stone or wrench is provided between the casing 40 and the auger screw 10. Biting, the auger screw 10 stops, and the problem of extremely high rotational resistance is avoided, so that excavation using the casing 40 such as the middle excavation method can be performed even on hard ground having a large stone diameter. It can be done reliably.

It should be noted that the present invention is not limited to the excavator 1 and the excavation method shown in this embodiment, but can be appropriately changed without departing from the gist of the invention. For example, as long as the configuration of the excavator uses a divisible auger screw, the configuration of a heavy machine that vertically holds the auger screw or a drive device that rotates and drives the auger screw is arbitrary. The excavation method is not limited to the mid-boring method, and if the work involves drilling in the ground using an auger screw, a method that does not use a casing, such as a cast-in-place pile method, a pre-boring method, and an underground continuous wall method. The same effect can be obtained for

[Second Embodiment] FIGS. 3A and 3B show a joint portion of an auger screw according to a second embodiment of the present invention. FIG. 3A is a side view thereof, and FIG. ) Arrow a-
It is a sectional view taken along line a and a sectional view taken along line bb. The auger screw 20 shown in FIG. 3 is mounted on the excavator 1 and used similarly to the auger screw 10 shown in the first embodiment. Omitted. The joint 6A of the auger screw 20 according to the second embodiment has a spline shaft 22 and a connecting shaft 23 protruding from one of the divided shafts 7b, and a spline hole 24 and a receiving hole for the connecting shaft 23 from the other divided shaft 7a. 25. As shown in FIG. 3B, the spline shaft 22 is formed by forming a spline on the outer peripheral surface of the shaft in the rotation direction of the auger screw 20, and has a smaller diameter than the shaft diameter of the divided shaft 7b. The same axis is protruded from the end face side of the divided shaft 7b. The connecting shaft 23 is provided with a through hole 23 a as a pin hole through which the connecting pin 28 penetrates, and protrudes from an end of the spline shaft 22.

The spline hole 24 and the accommodating hole 25 are for fitting the spline shaft 22 and the connecting shaft 23.
The same axis is bored on the end face of the divided shaft 7a. A spline is provided on the inner peripheral surface of the spline hole 24 so that the spline fits with the spline shaft 22 so as not to shift in the rotation direction of the shaft. As shown in FIG.
As shown in FIG. 5, a through hole 25a as a pin hole communicating with the accommodation hole 25 of the connection shaft 23 is formed. When the connection shaft 23 is inserted into the accommodation hole 25, the through hole 25a is formed.
The divided shafts 7a and 7b are joined by penetrating the connecting pin 28 into the through hole 23a of the connecting shaft 23 and hooking the connecting pin 28. The through-hole 25a of the split shaft 7a and the through-hole 23a of the connecting shaft 23 are formed at positions perpendicular to the axis and passing through the center of the axis. The through hole 25a of the split shaft 7a is provided at its end with a housing portion 25b for housing the head of the connecting pin 28, so that the outer peripheral surface of the shaft 7 forms a smooth continuous surface. I have. As described above, according to the excavator and the excavation method of this embodiment, in addition to the effects and advantages shown in the first embodiment, a strong and reliable connection can be performed.

[Third Embodiment] FIG. 4 is a side view of a joint 6B of an auger screw 30 according to a third embodiment. The auger screw 30 of the third embodiment
Is used by being mounted on the excavator 1 similarly to the auger screw 10 shown in the first embodiment,
The same components are denoted by the same reference numerals and description thereof is omitted.
As shown in FIG. 4, the joint 6B of the auger screw 30 of the third embodiment has a square tenon 32 on one of the divided shafts 7b.
And a mortise 34 is provided on the other split shaft 7a. The square tenon 32 is a tenon for a joint formed in a square shape so as not to be displaced with respect to the rotation direction of the shaft.
, And has the same axial center protruding from the end face side of the divided shaft 7b. Further, a pair of cutout grooves 33, 33 for latching the connecting pin are formed on both sides of the corner tenon 32 (sides when the longitudinal direction of the shaft 7 is viewed vertically). . The pair of cutout grooves 33, 33 are formed so as to be shifted in the longitudinal direction of the shaft 7, so that the thickness of the square tenon 32 cannot be made too large in order not to increase the diameter of the joint 6B. The strength reduction of the square tenon 32 is maintained by dispersing the strength reduction due to the notch grooves 33, 33 back and forth.

The mortise hole 34 is for fitting the square tenon 32, and has the same axis at the end face of the divided shaft 7a. The split shaft 7a is provided with through holes 36, 36 as pin holes communicating with the mortise hole 34. When the square tenon 32 is fitted into the mortise hole 34, a connecting pin is formed in the through hole 36, 36. (Not shown) through the notch 3 of the square tenon 32
By hooking the connecting pin on the third and third 33, the split shaft 7
a and 7b are joined. The through holes 36, 36 of the divided shaft 7a are perpendicular to the shaft 7 and have square tenons 32.
Are formed at positions passing through the notched grooves 33, 33. Since the pair of through holes 36 are also shifted from each other in the longitudinal direction of the shaft 7, the outer peripheral portion of the mortise hole 34 is too thick so as not to increase the shaft diameter of the joint 6B. Although it is not possible, the strength of the mortise hole 34 is maintained by dispersing the decrease in strength due to the through holes 36, 36 back and forth. Also,
At the ends of the through holes 36, 36 of the split shaft 7a, cutouts 35 are provided at the ends to prevent the head of the connecting pin from projecting from the outer periphery of the shaft 7. The connecting pins are provided with through holes 36, 36.
, Both ends of the connecting pin are made substantially flush with the outer peripheral surface of the shaft 7, whereby
In the state where the divided shafts 7a and 7b are joined, there is nothing other than the screw 8 in which the joint 6B has the same shaft diameter as the front and rear shafts 7 and protrudes from the outer peripheral surface of the shaft 7.

As described above, according to the auger screw 30 of this embodiment, the structure for hooking the connecting pin provided on the square tenon 32 is formed by a pair of notches formed on both sides of the square tenon 32 so as to be shifted back and forth. Since the grooves 33, 33,
It is easy to form, the manufacturing cost can be reduced, and the strength reduction of the square tenon 32 due to the formation of the notches 33 can be dispersed back and forth to maintain the strength. Similarly, mortise 3
The through holes 36, 36 provided on the side 4 are also shifted forward and backward, so that the strength of the mortise 34 can be maintained. That is, the joining portion 6B has a low manufacturing cost, can be joined securely, and has a high strength.

[0019]

According to the first aspect of the present invention, the ascending and discharging of earth removal along the axis of the auger screw is performed smoothly. Accordingly, an increase in the rotational resistance of the auger screw due to the catching of the earth at the joint is prevented, and the load on the motor for rotating the auger screw and the driving device for insertion can be reduced. Especially in the case of the middle boring method,
Stones and grinds are caught between the casing and the auger screw, which prevents problems such as stopping the auger screw and increasing the rotation resistance. Excavation using a casing such as a construction method can be reliably performed.

According to the second aspect of the present invention, rock clogging hardly occurs, and in particular, excavation using a casing such as a middle boring method can be reliably performed even on hard ground having a large stone diameter.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a state where an excavator according to an embodiment of the present invention is used for a middle boring method.

FIG. 2 is a side view showing an example of a joint portion of the auger screw of FIG.

3A and 3B show other examples of the joint portion, and FIG.
Is a side view thereof, and (b) is a cross-sectional view taken along line aa of FIG.
It is a sectional view taken on line b.

FIG. 4 is a side view showing another example of the joint.

FIG. 5 is a side view showing an example of a joint portion of a conventional auger screw.

FIG. 6 is a side view showing a state in which a conventional auger screw is used for a middle boring method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Excavator 6, 6a, 6b Joint part 7 Auger screw shaft 7a, 7b Split shaft 8 Screw 9 Auger head 10, 20, 30 Auger screw 12 Male screw 14 Female screw 22 Spline shaft 24 Spline hole 25 Connection hole for connecting shaft 32 Square tenon 33 Notch groove 34 Mortise hole 36 Through hole (pin hole)

Claims (2)

[Claims] 1. An excavator used for drilling a ground, comprising an auger screw comprising a shaft and a screw provided around the shaft, wherein the auger screw has a plurality of splittable and joinable shafts. An excavator, comprising a shaft, and a joint for joining these divided shafts is formed to have substantially the same diameter as the shafts before and after the joint. 2. An excavation method using the excavator according to claim 1, wherein the auger screw is assembled by joining the divided shafts, and is inserted into the ground while rotating the auger screw. An excavation method characterized in that soil is lifted up and discharged along an axis, and a perforation is provided in the ground.