JPS6037391A - Screw pipe for boring ground - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a screw pipe for drilling holes in the ground, which uses a casing made of steel pipe or the like to drill holes in the ground, and is capable of lifting even large gravel. Regarding screw pipes for drilling holes.

When creating foundation piles, there are two methods: drilling a hole from the ground surface and then erecting ready-made piles, or creating piles by pouring concrete, or using spring water with mortar, hardening agent, etc. without discharging the excavated soil. Methods such as injecting and kneading to create fill mortar piles are often used.

However, in any of the above-mentioned land preparations, an excavator is used to excavate the ground, but conventional excavators, as shown in Fig. 1, have screw blades 2 spirally formed around the outer periphery of a shaft 1, and the lower end An auger screw 4 having an excavating blade 3 is used, and if necessary, a casing 5 made of a steel pipe or the like is fitted around the outer periphery of the auger screw 4, and the auger screw 4 is connected to a drive section 6 of an excavator to drive it rotationally. By doing so, a hole is drilled in the ground, and the excavated earth and gravel is stored between the drilled hole or the inner peripheral surface of the casing 5 and the shaft 1, and is conveyed upward by 20 rotations of the screw blade, and then It is designed so that it can be discharged.

However, when drilling a hole in a place where the excavation ground is a gravel area and there are many large gravels, the size of the gravel A is limited by the hole or the gap between the inner surface of the casing 5 and the shaft 1 as shown in the second figure. Therefore, it becomes impossible to transport gravel larger than the gap, and there are problems such as being restricted by the ground where it can be used and having to use a casing 5 and auger screw 4 that are larger than necessary.

In view of this, the present invention has been made with the aim of solving the above-mentioned conventional problems.The present invention is made by fixing a screw blade member in a spiral shape to the inner circumferential surface of a casing made of a steel pipe or the like. Window holes are arranged at required intervals on the surface of the casing to allow the earth and sand to come into contact with the inner surface of the drilled hole in order to provide resistance to the earth and sand carried on the screw blades. The present invention provides a screw pipe for ground drilling in which a pipe for injecting a chemical liquid is spirally provided on the blade, and even gravel larger than the radius of the screw blade can be taken in and transported.

Two embodiments of the present invention will be described below with reference to the embodiments shown in FIGS. 3 to 9, and parts common to those in FIG. 1 are given the same reference numerals.

FIG. 3 shows the external appearance of the screw tube 7 according to the present invention, and FIG. 4 is an enlarged perspective view of a part thereof, showing a casing 8 made of a steel pipe or the like, and a screw tube fixed to the inner peripheral surface of the casing 8 in a spiral shape. It consists of a screw blade 9, and this screw blade 9 is axisless.

A required number of window holes 10, io, . As shown in the cross section of FIG. 5, this window hole has an opening width extending over y% of the circumference at a diametrically symmetrical position.

A chemical liquid injection pipe 11 for injecting mortar, soil hardening agent, etc. is spirally arranged on the screw blade 9, and the upper end thereof can be connected to a chemical liquid supply source for excavation. , the lower end is opened at the base of the excavation blade 12 at the lower end of the screw blade 9. For manufacturing the screw blade 9, for example, as shown in one plane in FIG. A large number of slits 14 are formed in the radial direction of the press-molded disk, and as shown in FIG. A screw shape is formed by sequentially connecting the lower edge of the slit 14 and the upper edge of the slit 14 of the next one by welding.Furthermore, welding to the casing 8 is performed by welding to the window holes 10, 10. You can do this by using...

Since the present invention has the above-mentioned configuration, when the screw pipe 8 is connected to the drive unit 6 of the side cutting rock and is driven to rotate to drill a hole in the ground, the excavation blade at the lower end of the screw blade 9]2
The earth and sand are excavated, and the excavated earth and sand are placed on the screw blades 9 and conveyed upward. During this conveyance, the window holes 10, 10, . . . opened in the casing 8 at
The earth and sand on the screw blade 9 comes into contact with the inner circumferential surface of the drilled hole at the part indicated by ・, receives frictional resistance, is transported upwards without slipping on the screw blade 9, and is discharged from the upper end of the casing 8 to the ground. be done.

If large gravel A is found during the above-mentioned excavation, it enters beyond the center of the screw blade 9 and is sent upward as shown in FIGS. 8 and 9.

When stirring the excavated soil and injecting mortar or the like, a chemical liquid may be injected through the pipe 11 during the drilling or drawing.

FIGS. 10 to 13 show modified examples of the present invention. The embodiment shown in FIG. In the embodiment, the window holes 10 are formed in an axially elongated oval shape, one of which is shown in FIG. 12, and are formed so as to be axially shifted from each other in the helical direction of the screw blades 9. In addition, as shown in g13, the window hole 10 may be a series of axially long holes. , and a digging blade 12 provided on the screw blade 9.
may not be made to protrude from the lower end of the casing 8, but may be positioned within the casing 8 as shown in FIG.

As explained above, in the present invention, the screw blades are threaded onto the inner peripheral surface of the casing without a shaft, and the holes are drilled by the lower end of the screw blades or the drilling blade at the lower end of the casing, so that the space between the screw blades is Even large gravel can be accommodated and carried upward without being obstructed by the shaft, and even in the ground where large gravel exists, holes can be drilled without any problem. In addition, a required number of window holes are made on the circumferential surface of the casing, and through these windows, the earth, sand, and gravel placed on the screw blades are brought into contact with the inner surface of the drilled hole, so that they receive operational resistance. Therefore, even if it is shaftless, it is ensured that it is carried upwards on the screw blade, and since the chemical liquid injection pipe is spirally provided on the screw blade, mortar and other chemical liquids can be injected. It has a glue effect such as.

[Brief explanation of drawings]

Fig. 1 is a top view showing a conventional excavator, Fig. 2 is a horizontal sectional view showing the state of gravel indentation by a conventional casing auger, and Fig. 3 is an embodiment of a screw pipe according to the present invention. Front view, Figure 204 is an enlarged view of the same part, Figure 5 is a horizontal cross-sectional view of the same part, %! Figures 6 and 7 are explanatory diagrams of one means for manufacturing the screw blades of the same screw pipe, and Figures 8 and 9 are the main parts 8...casing, 9...screw blades, 10...windows. Hole, 11... Pipe for chemical injection, 12... Drilling blade. Out 1 Representative Kiyoshi Inomata Figure 1 Hato 3 Ash ° 1 Figure 4 (9 ■ Figure 5 Figure 6 Figure 8 Kasumi Figure 7 Figure 3 Figure 9 Figure 10 Figure 11 Figure 1/ 1z Figure 13

Claims (1)

[Claims] It has a casing made of a steel pipe or the like, and a shaftless screw blade that is helically fixed to the inner circumferential surface of the casing. Window holes are arranged and opened at required intervals on the surface of the casing, and the screw blade is A screw pipe for ground drilling, in which a chemical liquid injection pipe is spirally provided, a drilling blade is provided at the lower end, and the upper end of the casing can be freely connected to the LTA moving part of an excavator.