JPS62233330A - Excavator for large-diameter pit - Google Patents

Abstract

PURPOSE:To a large-diameter pit at low cost by using a constitution in which the rotation of a penetrating rotary device is transmitted to an inner excavator through a torque bar, a turntable, and a kelly bar. CONSTITUTION:A base 13 and a turntable 14 are fitted with a kelly bar 8, and an excavator 5 is set in a casing pipe 4 under a condition that it is attached by a pin 7 to the lower end of the bar 8. The base 13 is set on the upper end of the pipe 4, a torque bar 12 is connected by a shear pin to a rotary device 2, and the excavator 5 is lowered to rockbed by sending out a rope 19. The rotary device 2 is turned to rotate the bar 12, the turntable 14, and the bar 8, whereupon the rotating force and vertical load of a weight 6 act on a cutter 5c to crush the rockbed.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a large-diameter drilling device for forming piles using the casing vibe construction method, and is particularly suitable for use when excavating rock. related to things.

(Prior art) As a known construction method for constructing cast-in-place piles using the all-casing construction method in ground with high excavation resistance such as bedrock, as described in Japanese Patent Publication No. 19836-1983, the inner diameter of the casing vibe is A method is known in which the center of the inside of a casing pipe built in I2E is excavated using a screw auger having an outer diameter, and then the remaining soil inside the casing pipe is excavated using an excavator and discharged.

However, according to this known construction method, one casing vibe
In addition to the push-in rotation device that pushes in while moving or rotating, it is also necessary to prepare a rotation device that excavates the ground in the casing pipe, which poses a problem of high costs.

(Problems to be Solved by the Invention) In view of the above-mentioned problems, the present invention is capable of not only setting up a casing vibrator but also rotationally driving an excavating tool for digging inside a casing pipe using a single rotating device. Moreover, it is an object of the present invention to provide a large-diameter vertical hole drilling device that requires small rotational torque.

(Means for Solving the Problems) The present invention provides the following advantages: a turntable centering base is installed on a casing pipe, and a turntable is rotatably installed on the base via a bearing. The Torque Par fixed to the table is removably connected to the rotating body rotated by the pushing rotation device of the casing pipe, and the Kerry bar can be moved up and down through the power transmission hole provided in the center of the turntable so as to rotate together with the turntable. The invention is characterized in that the Kelly bar is suspended via a swivel joint by a hanging lobe of a crane, and an excavating tool for medium digging to be inserted into the casing pipe is attached to the lower end of the Kelly bar. A casing pipe push-rotation device can be used as a driving source for the excavation tool, and there is no need to rotate the casing pipe.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. Reference numeral 4 designates a casing pipe having a cutter 4a at the lower end, and reference numeral 1 designates a pushing rotation device that loads the casing pipe 4 with a load and pushes it into the ground while rotating it. Although the details of the pushing rotation device 1 are not shown in the drawings, an outline thereof will be explained.

The base frame 1 is
The cylindrical rotating body 2 is rotated by a hydraulic motor (not shown) etc. installed on the lifting table 18 while lowering the lifting table 18 with respect to a, and the tightening force is applied to a hydraulic cylinder (
(not shown) and tightening are transmitted to the casing pipe 4 via the chuck device 3 consisting of a service band 3ai, thereby performing the erection of the casing pipe 4.

Reference numeral 5 denotes an excavator for digging into the casing pipe 4, and the excavator 5 is the lower end of the telescopic Kelly bar 8 (ie, the outer rod 8a having a rectangular cross section).

A cylindrical shaft 5a that is removably connected to the lower end of the inner rod 8c of Kerryba consisting of a center rod 8b and an inner rod 8c by a pin 7, and a plurality of wings 5b radially provided at the lower end of the cylinder +jh5a; It consists of a cutter 5c provided on the lower surface of each i5b, and a disc-shaped weight 6 for applying an excavation thrust is attached to the cylindrical shaft 5a. The inner rod 8c is connected to a suspension lobe 19 of a crane (not shown) via a swivel joint 11 and a support lobe 10 inserted into the Kelly bar 8.

t) The 11th Kerry bar 8 is moved from the rotating body 2 to the torque par 1.
The rotational force is transmitted through the turntable 2 and the turntable 14. That is, as shown in FIGS. 1 to 4, a turntable centering base 13 made of a circular plate having a round hole 13a through which the Kelly bar 8 is inserted and a fitting edge 13b is installed at the upper end of the casing pipe 2. A turntable 14 is rotatably installed on the base 13 via a bearing 15, and a plurality of inverted torque bars 12 are fixed radially to the turntable 14. The straight part is removably connected to the rotary body 2 by a shear bin 17, and the seven outer rods 8a of the Kelly bar 8 are slidably fitted into a rectangular hole 14a for power transmission provided at the center of the turntable 14. The rotational force of the rotating body 2 is l·Lukbar 12. Turntable 1
The signal is transmitted to the keiriva 8 via the channel 4.

Further, at the upper end of the seventh outer rod 8a of the Kelly bar 8, there is an upper plate 9a fixed to the outer rod 8a, and an upper plate 9a fixed to the outer rod 8a.
a lower plate 9b slidably fitted to a, and both plates 9a, 9b.
A stopper 9 with a shock absorber of a Kelly bar 8 is provided, which is made up of a spring 9c interposed between the plates 9a and 9b and connected to each other.

When using this device to excavate in bedrock, attach the base 13 and turntable 14 to the Kellyba 8.
and with the excavator 5 attached to the lower end of the Kelly bar 8 by the pin 7, the excavator 5 is suspended into the casing pipe 4, the base 13 is installed on the upper end of the casing pipe 4, and the torque par 12 is rotated. The excavator 5 is connected to the body 2 by a shear bin 17, and the lobe 19 is let out to lower the excavator 5 and reach the bedrock, and the rotating body 2 is rotated once. Rotate A5. As a result, the cutter 5C of the excavation tool 5 is subjected to a rotational force due to the eave direct load m by the weight 6 and the rotational torque transmitted via the Kelly bar 8, and these forces cause the cutter 5C to bite into the rock.
Crush the bedrock. In this way, it becomes possible to perform digging in the ground made of rock by using the rotational drive device of the push-in rotation device 1. Also, at this time, the chuck is installed! i
3 is left open, the rotational force of the push-rotation device 1 is not transmitted to the casing pipe 4, which remains stationary, and the rotational force of the push-rotation device 1 can be effectively utilized.

The gravel produced by crushing can be discharged using a talam shell packet or the like after being pulled up by the excavation A5.

In addition, in this embodiment, since a stopper 9 with a shock-absorbing neck for the Kellyba 8 is provided, even if the Kellyba 8 falls for some reason, the stopper 9 will act, so that the Kellyba 8 will not collide with the turntable 14. This prevents the Kerry bar 8 from being damaged due to mechanical damage, and also prevents the Kerry bar 8 from being buried in the hole being excavated. In addition, the pushing rotation device l has
Although it is equipped with a rotating torque and TjJ111 device,
- If excessive rotational torque is applied for some reason, the shear pin 17 will not break and the structural members will not be damaged.
Since the casing pipe 4 is detachably connected, it can be easily replaced with an appropriate one according to the diameter of the casing pipe 4, the hardness of the rock, the condition, etc.

5 and 6 show other embodiments of the present invention, in which a roller 16 is provided on the inner wall of the power transmission hole 14a of the turntable 14, so that the Kelly bar 8 can be smoothly moved up and down. This is what I did. Note that the hole 14a of the turntable 14 is not limited to a rectangular shape, and may have any other shape as long as it can sufficiently transmit rotational torque.

(Effects of the Invention) As described above, the large-diameter drilling equipment of the present invention transmits the rotational force of the pushing rotation device to the medium drilling tool through the torque bar, the turntable, and the Kelly bar. The device 1 for pushing and rotating the casing pipe is constructed so that it can be dug inside.
The platform can excavate the ground inside the casing pipe, making it possible to create large-diameter piles at low cost. Also.

Since the drilling tool is rotated using a rotating device with a large rotational force that rotates the casing pipe, any large diameter hole can be prepared easily by using a drilling tool suitable for the diameter.
Moreover, the entire interior can be thoroughly excavated. Also,
If a drilling tool is inserted into the casing pipe, and the torque transmission projection provided on the inner wall of the casing pipe is engaged with the outer periphery of the drilling tool, and the drilling tool for medium digging is rotated together with the casing pipe, the projection 1111 However, according to the present invention, these forces are unnecessary and can be effectively used for excavation without significantly increasing the output of the single-rotation device. , can be economically excavated,
Furthermore, since there is no excavation resistance due to the protrusions, excessive rotational torque is not required when erecting the casing pipe.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view showing an embodiment of the present invention, Fig. 2 is an enlarged view of the construction part in Fig. 1, Fig. 3 is a sectional view taken along line E-E in Fig. 2, and Fig. 4 is a sectional view of Fig. 1. 5 shows another embodiment of the present invention. JSZ diagram equivalent diagram, Figure 6 is F-F of Figure 5
FIG.

Claims (1)

[Claims] A turntable centering base is installed on the casing pipe, and the turntable is rotatably installed on the base via a bearing, and a torque bar fixed to the turntable is rotated by the pushing rotation device of the casing pipe. The Kelly bar is removably connected to the rotating body, is inserted into a power transmission hole provided at the center of the turntable so as to be vertically movable so as to rotate together with the turntable, and the Kelly bar is connected to the rotating body via a swivel joint by a hanging rope of a crane. 1. A large-diameter hole-forming drilling device, characterized in that a drilling tool for medium digging, which is inserted into a casing pipe, is attached to the lower end of the kely bar.