JPS5822630B2 - How to add screw auger with casing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of refilling a screw auger with a casing.

Conventionally, when excavating pile holes for laying concrete piles, etc., in collapsible ground, etc., a screw with a casing was used as a method to continue excavating while maintaining the pile hole that had been excavated with a screw auger. Augers were sometimes used.

The present invention relates to an improvement over the prior art in this regard.
In particular, the object is to provide a method that allows the rotating casing to expand and contract, thereby allowing for the addition of screw augers and casings.

To specifically explain the embodiment shown below, FIGS. 1 and 2 are partially cut-away front views of the device showing the expansion and contraction state of the casing, and 1 is a screw in the upper part that is directly connected to the rotary drive unit 2. The auger is shown and consists of a hollow auger shaft 1a and a spiral portion 1b.

Reference numeral 3 denotes a rotary casing, which is attached to the auger 1 and is free to rotate with respect to the auger 1. Several blade-like protrusions 4 are vertically attached to the outer periphery of the upper end in a radial manner. An earth discharge port 5 for discharging earth and sand lifted by the auger 1 is bored at an appropriate position in the protruding part.

A drive casing 6 is provided externally around the screw auger 1 on the lower surface of the rotary drive unit 2 and is rotated in the opposite direction to the auger 1, and its upper end is connected to the inside of the drive unit 2.

A vane-like protrusion 7 corresponding to the vane-like protrusion 4 at the upper end of the rotary casing 3 is provided centripetally and vertically on the inner periphery of the drive casing 6, and both casings 3.degree. The protrusions 4 and 7 are loosely fitted into each other at the projecting portions, and the protrusions 4 and 7 come into contact with each other, so that the rotation of the drive casing 6 is transmitted to the rotary casing 3.

The protrusions 4 and 7 also function as guides when the casing 3 moves up and down, and are an important component of the present invention, particularly in allowing the casing to expand and contract.

That is, the rotating casing 3 is raised and lowered by the telescopic drive mechanism described below even while the casing is rotating.
At this time, the outer diameter of the protrusion 4 is configured to be slidably and loosely fitted within the inner diameter of the drive casing 6, and the inner diameter of the protrusion 7 is configured to be slidably fitted to the outer periphery of the rotating casing 3. , both casings 3 and 6 and the auger screw 1 are always held concentrically.

Reference numeral 8 denotes a bracket protruding from the outer periphery of the rotary drive unit 2; 9, the center of which is rotatably fitted near the lower part of the protrusion 4 of the rotary casing 3; arms 10 are integrally protruded from both sides; The frame 11 is a thrust bearing or other bearing portion that holds the frame 9 from above and below so as to fix the vertical position of the frame 9 on the outer periphery of the casing 3.

Reference numeral 12 denotes a jack consisting of a fluid pressure cylinder or the like, which is installed between the arm 10 and the bracket 9, and moves the casing 3 up and down (extensions and contractions) by its expansion and contraction operation.

The casing expansion/contraction device configured as described above is operated from the soil discharge port 5 while excavating the ground using the screw auger 1 whose tip protrudes from the tip of the casing 3 (or the casing further joined to the lower end of the casing 3). During excavation and removal, and at the same time penetrating into the ground together with the outer casing 3, the casing 3 also rotates in the opposite direction to the auger 1 and is expanded and contracted by the jack 12 (see Figure 2), as will be described later. It has various effects.

Next, the connection work of the auger and casing performed by the above-mentioned apparatus will be explained based on FIGS. 5 to 9.

Adding screw augers and casings is necessary when the initially installed auger has been excavated to the maximum possible depth and it is necessary to excavate even deeper, and is carried out as follows.

Figure 5 shows the state in which excavation with the initially installed casings 3, 3' and screw augers 1, 1' has been completed, and Figure 6 shows the state in which each connection is removed in order to add casings and augers. .

Here, the casings 3, 3' are first separated, the upper casing 3 is raised a certain distance by a telescoping device, and then the augers 1, 1' are disconnected.

Next, as shown in FIG. 7, the casing 3 and the auger 1 are lifted upward, and while doing so, first the upper end of the auger 1' and the lower end of the auger 1 are connected, and then the upper end of the casing 39 and the lower end of the casing 3 are connected.

Next, the lower end of the auger 11 and the upper end of the auger 1' are connected (Fig. 8), and then the casing 3' connected to the casing 3 is lowered by the distance previously raised by the telescoping device, and the lower end of the casing 3' is lowered. Connect the upper end of the g to complete the connection of all casings and augers (Figure 9).

Similar operations may be performed below as needed.

As mentioned above, according to the method of the present invention, when constructing long piles, by expanding and contracting only the casing, it is possible to easily add screw augers and casings, and in collapsible ground, simply removing the jack of the expansion device This has great technical effects, such as the ability to easily remove only the auger and construct piles while leaving the casing in the ground.

[Brief explanation of the drawing]

Figures 1 and 2 are partially cut-away front views of the device showing the expanded and contracted state of the casing, and Figures 3 and 4 are A--A in Figure 1.
A and BB sectional views and FIGS. 5 to 9 are explanatory front views showing the state of the connection work of the casing and screw auger. The symbols in the figure indicate the following parts. 11'1"・Song・9 Screw auger, 1a・・Song auger shaft, 1b・・
...Spiral part, 2...Four rotation drive part, 33' la 2 γ...Rotating casing, 4...Face protrusion, 5.
... Soil discharge port, 6. Curved drive casing, 7. Surface protrusion, 8. Bracket, 9. Frame, 1o. Curved arm, 11. Curved bearing. , 12・Song・Jyatsuki.

Claims (1)

[Claims] 1. A screw auger with a rotational drive section attached to the upper part, a drive casing which is mounted on the upper end of the screw auger and whose upper end is connected to the rotational drive section to receive rotational drive in the opposite direction to the screw auger, and a drive casing through which the screw auger is inserted. A rotary casing whose upper end is slidably fitted to the drive casing and receives rotational drive thereof, and a jack interposed between a frame that rotatably supports the rotary casing and the rotary drive section. First, connect the lowermost rotating casing and the lowermost screw auger inside the rotating casing to the lower ends of the rotating casing and the screw auger inside the rotating casing, using a casing expansion and contraction device consisting of a casing expander, and excavate in a conventional manner. Once completed, the connection between the rotating casing and the lowermost rotating casing is removed, and the space created by lifting the rotating casing with the jack is used to disconnect the screw auger from the lowermost screw auger. Lift up the rotating casing and the internal screw auger at the same time, connect the next rotating casing and the next screw auger to their respective lower ends, and then attach the next screw auger onto the bottom screw auger. Then, the jack lowers the connected rotating casing and the next rotating casing, connects the next rotating casing onto the lowermost rotating casing, and excavates in a conventional manner. , a method for adding a screw auger with a casing, characterized by repeating the above steps.