JPS649411B2 - - Google Patents

Description

Detailed Description of the Invention (Object of the Invention/Field of Industrial Application) The present invention is used in the field of improving soft ground.

The present invention inserts a casing into the ground to a predetermined depth, fills the casing with sand, and then supplies pressurized air into the casing to push out the sand while pulling out the casing. The present invention relates to a sand drain driving device used in a sand drain driving method for creating sand piles.

(Prior art) In conventional so-called driving-type sand drain installation equipment, a steel pipe called a mandrel is driven in using a drop hammer, an exciter, etc., and the ground is considerably disturbed by driving the mandrel with the drop hammer or the like. At the same time, there was a problem that noise and vibration were generated during driving.
In addition, so-called auger-type sand drain casting equipment has been used in the past, in which an earth auger is inserted into the casing and the casing is lowered while excavating the ground with the auger. Since no exciter is used, problems with noise and vibration can be solved, but on the other hand, the auger must be removed when the casing reaches a certain depth during construction, and the operation of removing the auger requires considerable time and labor. Therefore, there was a problem that construction efficiency was poor.

In addition, in general, sand drain casting equipment is used to check the supply status of sand supplied into the casing when pulling out the casing. A weight type sand surface detection device is used to detect whether sand is being pushed out and discharged. In this device, for example, a string extending from a torque winch from the main body of the detection device installed on the crane supporting the leader is suspended into the casing from above, and a weight attached to the tip is attached to the upper surface of the loaded sand. (Sand surface)
In order to maintain balance in this resting state, the string is made to maintain tension, and as the sand surface inside the casing descends as the casing is pulled up, it suspends the weight on the sand surface. The cord is let out by the torque winch, and the flow and discharge state of the sand is checked while measuring the amount of the let-out of the cord on the detection device main body side. However, with conventional sand drain casting equipment, sand is directly thrown into the rotating casing, so if the casing is pulled out while rotating, the sand inside the casing will rotate with the casing. As a result, the sand surface detection device described above cannot be applied; in other words, the weight placed on the sand surface moves as the sand rotates, making it impossible to perform proper detection.
Therefore, when detecting the sand surface, the work of pulling out the casing must be interrupted, which reduces the efficiency of the sand drain casting work.

(Object of the Invention) An object of the present invention is to provide a sand drain casting device that can solve the problems of the conventional device as described above.

(Structure of the Invention) The device of the present invention for achieving the above-mentioned object is connected to the lower part of the machine frame suspended by the leader, has a screw on the outer peripheral surface, and has a screw provided on the machine frame. A rotary casing rotated by a rotary drive means, a fixed casing whose upper end is fixed to the machine frame side and fitted into the rotary casing over the entire length of the rotary casing, and a fixed casing installed at the upper end of the fixed casing. a hopper for feeding sand into the fixed casing; an on-off valve provided at the upper end of the fixed casing to seal the fixed casing; a pressurized air supply means for supplying pressurized air into the fixed casing; A vibrator is installed at the lower end of an inner rod that is inserted into the casing. It is characterized in that it is attached to a mounting frame member having a flow path.

(Example) Next, an example of the present invention will be described based on the drawings.

Fig. 1 shows an overall view of the sand drain casting device according to the present invention, and in this figure, 1 is a machine frame that is vertically suspended from a leader (not shown) installed on a crawler crane or the like. So, this machine frame 1
At the bottom of the
A cylindrical rotary casing 3 having a screw threaded thereon is rotatably suspended, and a bottom cover 4 is attached to the lower end of the rotary casing 3 so as to be openable and closable. A rotary drive device 5 for rotating the rotary casing 3 is disposed within the machine frame 1, and a short cylindrical upper fixed casing 6 is disposed above the rotary casing 3 and concentrically with the casing 3. is fixed to the machine frame 1, and a hopper 7 for supplying sand is installed at the upper end of this upper fixed casing 6, and inside this upper fixed casing 6, the upper end opening of the fixed casing 6 leading to the hopper 7 is sealed. An on-off valve 8 that can be closed at any time and this upper fixed casing 6
An air supply nozzle 9 is provided as a means for supplying pressurized air into the interior. Further, an upper end portion of a hollow shaft-shaped inner rod 10 is fixedly attached to the inside of the upper fixed casing 6 via a mounting frame member 11. This mounting member 11 includes an inner ring part 11a into which the upper end of the inner rod 10 is fitted and fixed, an outer ring part 11b which is fitted and fixed to the inner peripheral surface of the upper fixed casing 6, and these inner ring parts 11a and It is composed of a plurality of ribs 11d interconnecting the outer ring portion 11b and forming a sand and air flow path 11d between them. This inner rod 10 extends to near the lower end of the rotating casing 3, and a vibrator 12 is installed at the lower end of the inner rod 10. Furthermore, an elongated cylindrical lower fixed casing 13 with a diameter slightly smaller than that of the casing is fitted into the rotating casing 3 so as to extend over the entire length of the rotating casing 3 and to allow rotation of the rotating casing 3. The upper end of the fixed casing 13 is integrally connected to the lower end of the upper fixed casing 6 and is fixed to the machine frame 1.

As shown in FIG. 1, the rotary drive device 5 rotatably supports a large gear 14 at the bottom of the machine frame 1, and integrally connects the lower end of the large gear 14 with the upper end of the rotating casing 3. , a pair of electric motors 15, 15 with reduction gears are disposed at opposing positions on both sides of the upper fixed casing 6 in the machine frame 1, and these electric motors 1
Small gear 1 fixed to output shafts 16, 16 of 5, 15
7 and 17 are meshed with the large gear 14 at both sides thereof, and the rotation of both electric motors 15 and 15 in the same direction rotates the rotating casing 3 via the small gears 17 and 17 and the large gear 14. That's what I do. The large gear 15 is located in the upper fixed casing 6
It is rotatably fitted to the machine frame 1 through bearing devices 18 and 19 that support both radial and thrust loads, respectively, and is held so as to be rotatable and immovable up and down. The bottom cover 4 consists of two halves 4a, 4a, which are formed by vertically dividing an inverted cone with a hollow interior, into a rotating casing 3.
It is screwed onto the lower end of the rotating casing 3.
Normally, when the rotating casing 3 is suspended above the ground, it is open as shown by the solid line in Figure 1, and when the rotating casing 3 penetrates into the ground, it is shaped like an inverted cone as shown by the imaginary line in the same figure. When the rotary casing 3 is pulled up through the ground, it assumes the open position shown by the solid line in the figure. The on-off valve 8 has a valve port 2 as shown in FIGS. 3 to 5.
A valve receiver 21 and a valve port 20 having an elliptical shape in a plan view having a diameter of 0
It consists of a valve body 22 that opens and closes the valve body 2.
1 is fixed to the upper end of the short upper fixed casing 6 in an inclined position, a packing 23 is attached to the lower peripheral edge of the valve port 20, and a valve body 22 is arranged below the valve receiver 21. The support frame 2 fixed to the hinge member 24 of the valve receiver 21 and the lower surface of the valve body 22
5 and a hinge member 26 at one end thereof are screwed together with a pin 27, thereby making it possible to open and close the valve body 22 with respect to the valve port 20. Normally, this valve body 22 is
It is in the open state at the position shown by the dashed line in the figure,
When pressurized air is supplied from the air supply nozzle 9 into the upper fixed casing 6, the valve element 22 is pressed upward and rotated upward by the pressure air jetted from the tip of the nozzle 9, and is held in the closed position, thereby closing the valve. It's becoming like that. In addition, instead of performing the closing operation of the valve body 22 by such air pressure, as shown by the two-dot chain line in FIG. A spring member 28 is interposed between the valve body 22 and the valve body 22 by the spring force under normal conditions.
Alternatively, the valve body 22 may be held in the closed position, and the weight of the sand may be used to open the valve body 22 against the force of the spring when sand is introduced from the hopper 7.

FIG. 6 shows a cross-sectional view of the vibrator 12. This vibrator 12 is made of a vibro float, and as shown in FIG. The eccentric shaft body 31 is integrally connected to the output shaft of the float body 29 in the lateral direction (in the axial direction of the inner rod 10 and It is designed to produce vibrations in the intersecting directions. The float body 29 is connected to the lower end of the inner rod 10 via a coupling 32. Further, a cap tire 33 for the electric motor 30 is inserted into the hollow portion 10a of the inner rod 10 from a required portion at the upper end of the inner rod 10, and is connected to the electric motor 30 within the float body 29.

Next, a method of using the sand drain casting device having the above-mentioned configuration will be explained with reference to FIGS. 7A to 7E.

First, with the elevator frame 1 of this machine suspended and supported at an appropriate height from the top of the leader (not shown), the rotary drive device 5 is activated to rotate the rotary casing 3 in the forward direction, and the lifting operation wire (Fig. (not shown)
The rotary casing 3 is lowered by letting out the rotary casing 3, and penetrates into the ground G. At this time, when the bottom cover 4 at the lower end of the rotating casing 3 hits the ground G, the bottom cover 4 closes as shown in FIG. 7A. In this way, the rotating casing 3 is inserted into the ground while rotating, and when it reaches a predetermined depth, it is inserted into the elongated lower fixed casing 13 through the upper fixed casing 6 which is shorter than the hopper 7, as shown in FIG. Fill with the required amount of sand. After filling the sand, as shown in FIG. The on-off valve 8 is operated to the closed position by the pressure of the air, and by closing the on-off valve 8, the air pressure in the internal space extending from the inside of the upper fixed casing 6 to the inside of the lower fixed casing 13 is increased, while the vibrator 12 starts operating and adds vibration to the surrounding sand. The sand filled in the lower fixed casing 13 is pressed by the pressurized air from the upper part of the lower fixed casing 13 and is vibrated in the lower part of the lower fixed casing 13 to compact and compact the sand, and at the same time, the rotating casing 3
The rotary casing 3 is pulled up while rotating in the opposite direction to the direction in which it was inserted and winding up the wire for lifting and lowering the machine frame 1. When the rotary casing 3 is pulled up in this way, the bottom cover 4 opens and the compacted sand is removed. The sand pile P is gradually formed while being pushed out from the lower end of the lower fixed casing 13 (7th
(See Figures D and E). In addition, the sand thrown in when the rotating casing 3 is pulled up is removed from the rotating casing 3.
When detecting the sand surface using a weight-type sand surface detection device in order to confirm whether the sand is being pushed out from the lower end, the sand is substantially inside the elongated lower fixed casing 13. Since the sand inside the rotating casing 3 does not rotate as the rotating casing 3 rotates, the sand inside the sand does not rotate when the rotating casing 3 is pulled up while still rotating. Detection can be performed accurately. In FIG. 1, W indicates a weight for detecting the sand surface, which is suspended from the string H, and S indicates the sand surface.

(Effects of the Invention) The sand drain casting device of the present invention penetrates the rotating casing to a predetermined depth into the ground while rotating the rotating casing, which has a screw on the outer peripheral surface and has a vibrator inserted into the lower part of the inside. The casing is constructed so that a sand pile is created in the ground by pressing the sand inside with pressurized air and pulling out the casing while applying vibration to the sand with a vibrator. Since the rotary casing with a screw is inserted while rotating instead of being inserted by driving with a screwdriver, an electric motor etc. can be used as the casing driving means, and a vibrator is installed inside the casing at the bottom. Together with this, it is possible to almost eliminate the generation of noise and vibration on the ground, and since the casing itself has the function of an earth auger, it is possible to eliminate the casing during construction, unlike conventional so-called auger type sand drain casting equipment. There is no need to remove or insert the earth auger from inside, and therefore, the pile construction work can be carried out efficiently without any extra work or effort.
Furthermore, in the device of the present invention, in addition to the pressing action of the pressurized air by the pressurized air supply means, the sand is compacted by the vibration action of the vibrator inside the fixed casing, so that a denser sand pile can be formed. Furthermore, according to the device of the present invention, since the fixed casing is inserted into the rotating casing over the entire length of the casing, the sand that is thrown in is substantially accumulated in the fixed casing.
Even if the rotating casing rotates, the sand itself is not rotated. Therefore, when detecting the sand surface to confirm the state of extrusion and discharge of the inserted sand, the rotation of the rotating casing is stopped. There is no need to interrupt the extraction work, and the construction work can be carried out continuously.

Furthermore, in the sand drain casting device of the present invention, the upper end of the inner rod, which is equipped with a vibrator at the lower end, is fixed to the inner circumferential surface of the fixed casing below the on-off valve, and the sand and air flow path Because it is attached to a mounting frame member having a The flow of sand or air supplied from the pressurized air supply means is not obstructed.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional front view of a sand drain casting device showing an embodiment of the present invention, Fig. 2 is a sectional view taken along the line - - in Fig. 1, and Fig. 3 constitutes the on-off valve in Fig. 1. A bottom view of the valve receiver, FIG. 4 is a bottom view of the valve body, and FIG. 5 is a vertical sectional view showing the mounting structure of the on-off valve.
FIG. 6 is an enlarged sectional view showing the vibrator, and FIGS. 7A to 7E are explanatory views showing how to use the sand drain casting device. 1... Machine frame, 2... Screw, 3... Rotating casing, 5... Rotating drive device, 6... Short upper fixed casing, 7... Sand charging hopper,
9... Air supply nozzle (pressure air supply means), 1
0... Inner rod, 11... Mounting frame member, 12... Vibrator, 13... Long lower fixed casing.

[Claims]

1. A plurality of hulls 1, 1'... are arranged horizontally in a row with a predetermined distance between them, and the hulls are connected to each other,
An endless rotating drive body 3 having a large number of scrapers 2 protruding from all or part of the plurality of hulls is wrapped around the hull, and a continuous rail 4 extending across the group of hulls above the hull,
A hardening treatment machine 6 having stirring blades 5 is installed on the same rail so as to be freely movable, and a plurality of floats are arranged horizontally at the front and rear parts between the hulls, separated by a required distance. , and a hardening treatment device for soft ground comprising the same float that can be raised and lowered freely.