JPS648126B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Use) The present invention is used in the field of improving soft ground.

The present invention relates to an apparatus for constructing sand piles on soft ground, and more particularly to an apparatus for constructing sand piles without vibration or noise.

(Prior art and its problems) There are sand pile making devices that have already been filed and published by the applicant of the present invention (Japanese Patent Application No. 152835/1983 (Japanese Unexamined Patent Publication No. 77715/1989) and others). This device forcibly vibrates an outer tube and an inner tube inserted into the outer tube using a vibrator connected to the upper end of the inner tube while penetrating into the ground, and after the outer tube reaches a predetermined depth, Sand is introduced into the outer tube from the hopper, while the inner tube is vibrated by a vibrator and simultaneously moved up and down with a relatively long stroke by a fluid pressure cylinder that drives the inner tube up and down, tamping the sand in the outer tube. However, the outer pipe and inner pipe are pulled out to form a sand pile.This device has the great effect of sufficiently compacting the sand in the outer pipe to create a strong sand pile. On the other hand, since a vibrator is used and the vibrator vibrates the inner tube and the outer tube, it has the disadvantage of generating severe noise and vibration during operation. In addition, the so-called auger-type sand drain driving machine, which has traditionally been used as a device that generates less noise and vibration, lowers the casing while excavating the ground by inserting an earth auger into the casing. This device removes the auger when it reaches a certain depth, throws sand into the casing, and then pulls out the casing to create a sand pile, but the sand is not compacted inside the casing. Therefore, there are many disadvantages such as the strength of the sand piles that are formed and the construction ability is low.

The present invention solves the conventional difficulties, and provides a sand pile construction device that can minimize the generation of noise and vibration during work, and can form sufficiently consolidated and strong sand piles. With the goal.

(Technical Means for Solving the Problems) To achieve the above object, the sand pile construction device of the present invention has an elevator frame that is suspended along a leader so as to be able to rise and fall freely, An outer tube with a screw threaded thereon is connected to the outer tube so as to be rotatable, and a middle tube with a screw threaded on at least the lower end of the outer periphery is rotatably inserted into and supported by the outer tube. An inner tube serving as an air supply path is inserted, and the large-diameter head at the upper end of the inner tube is supported relative to the upper end of the middle tube so that it can rotate freely, and an air hammer is attached to the lower end of the inner tube protruding from the lower end of the middle tube. A sand charging hopper for charging sand into the outer pipe is connected to the outer pipe through a fixed pipe supported by the elevator frame, and the upper part of the sand charging hopper is placed in the upper part of the outer pipe at a symmetrical position on both sides of the fixed pipe. A pair of inner tube drive motors are installed on both sides, and a pair of outer tube drive motors are installed on both sides at the lower side. A required gap is provided between the lower end and the upper end of the lower tube part, and a large gear on the middle tube side fixed to the upper end of the middle tube is inserted airtightly through the gap and protrudes outside the outer tube. , is meshed with the output gear of each of the middle tube drive motors, and the large gear on the middle tube side is provided with an opening for circulating sand and air;
In addition, a large gear on the outer tube side fixed to the upper end of the outer tube is meshed with the output gear of each of the outer tube drive motors, and an air supply pipe for sand pressing is connected to the fixed tube, and the fixed tube and hopper are connected to each other. An on-off valve is provided between the

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

Figure 1 shows an overall diagram of the sand pile construction equipment. In this figure, 1 is an elevator frame that is suspended from a leader (not shown) installed upright, such as a crawler crane, so that it can be raised and lowered. 1, an outer tube 3 having a screw 2 screwed thereon over the entire length of its outer periphery, and an inner tube 5 fitted into the outer tube 3 having a screw 4 screwed onto the lower end of the outer periphery are connected to each other so as to be freely rotatable. An inner tube 6 having an air supply path 6a inside is inserted into the inner tube 5 in a loosely fitted state.
An air hammer 7 is attached to the lower end of the inner tube 2 protruding from the lower end of the middle tube 5, and a drive device 8 for rotating the outer tube 3 and a drive device 9 for rotating the middle tube 5 are installed in the elevator frame 1. In addition, a hopper 10 for feeding sand into the outer tube 3 is provided, and a fixed tube 11 having the same diameter as the outer tube 3 is interposed between the hopper 10 and the outer tube 3. An on-off valve 12 is provided at the connection between the fixed pipe 11 and the hopper 10, and an air supply pipe 13 for operating the air hammer is connected to the upper end of the inner pipe 6. A pipe 14 for supplying air for sand pressing into the outer tube 3 through the fixed tube 11 is connected to the upper end of the tube 11 .

To explain the above structure in more detail, the outer tube rotation drive device 8, as shown in FIGS. 1 and 2, rotatably supports a large gear 15 at the lower part of the elevator frame 1. While the lower end is integrally connected to the upper end of the outer tube 3, a pair of reducer-equipped motors 16, 16 are installed at symmetrical positions on both sides of the fixed tube 11 within the elevator frame 1, and these motors 16, 16
A small gear (output gear) fixed to the output shaft 17, 17 of
18, 18 are meshed with the large gear 15 at both sides thereof, and the rotation of both motors 16, 16 in the same direction rotates the outer tube 3 via the small gears 18, 18 and the large gear 15. I'm starting to let them do it. The fixed pipe 11 has an upper pipe part 11a and a lower pipe part 11.
b, and these upper and lower pipe parts 11a, 1
1b is disposed coaxially above the outer tube 3, and is spaced apart from the lower end of the upper tube portion 11a and the upper end of the lower tube portion 11b with a required distance from each other to the elevator frame 1, as shown in FIG. Fixed. The middle tube rotation drive device 9, as shown in FIG.
A pair of reducer-equipped motors 20, 20 are provided on both sides of the fixed pipe 11, and are fixed to the middle pipe 5 in a rotatable manner within the space between the fixed pipe 11 and the lower pipe part 11b. , 20 output shafts 21, 2
As shown in FIG. 3, small gears (output gears) fixed at 1 and 22, 22 are meshed with a large gear 19, and the rotation of motors 20, 20 causes the small gears 22, 22, 22 to mesh with the large gear 19.
22 and a large gear 19 to rotate the middle tube 5. As is clear from FIG. 3, the large gear 19 has a plurality of fan-shaped openings 19a formed between its central shaft and peripheral teeth, and the fixed tube 11
Sand and air inside can flow through this opening 19a. In addition, the upper tube part 11
The gap between the lower end a and the upper end of the lower tube part 11b is the large gear 19.
The middle tube 5 is sealed by a seal ring 23 disposed on the upper surface side and a seal-bearing 24 disposed on the lower surface side supporting the large gear 19. It is rotatably supported by support members 25 as shown in FIGS. 1 and 4 provided at required portions. As shown in FIG. 5, the inner tube 6 has a large-diameter head 6b that is connected to the inner tube 6 through a ring-shaped cushion member 26 in order to allow rotation of the inner tube 5 and to prevent vibrations of the inner tube 6 from being transmitted to the inner tube 5. Middle tube 5
It is supported at the upper end, and the upper end of the air supply path 6a of the inner tube 6 passes through the upper end 11a.
It is connected to the air supply pipe 13. The air supply pipe 13 and the sand pressing air supply pipe 14 are each connected to an air compressor (not shown).

As shown in FIGS. 6 to 9, the air hammer 7 includes a body 28 having a sliding chamber 27 and connected to the lower end of the inner tube 6, and a pressure chamber 29 inside the sliding chamber 27 of the body 27. It consists of a piston 30 that reciprocates, and a head plate 31 attached to the tip of the piston 30. First, pressurized air from the air supply path 6a of the inner tube 6 is introduced into the introduction path 32 through the inlet hole 32a of the body 28. The air is introduced into an annular intermediate chamber 34 through a plurality of communication passages 33 extending in the axial direction, and the pressurized air from this intermediate chamber 34 is transferred to an annular variable volume chamber 35 between the sliding chamber 27 and the piston 30. At the same time, the piston 30 enters the pressure chamber 29 through a plurality of communication holes 36 provided in the piston 30. At this time, due to the difference in pressure receiving area between the annular variable volume chamber 35 side and the pressure chamber 29 side, the piston 30 having a larger pressure receiving area is pushed downward with respect to FIG. Annular outlet side chamber 3 on the side
7, the pressure air in the pressure chamber 29 flows from the communication hole 36 and the outlet side chamber 37 to the body 2.
The air is discharged to the atmosphere from the upper end surface side of the body 28 through a plurality of exhaust passages 38 extending in the axial direction of the variable volume chamber 35, thereby reducing the air pressure in the pressure chamber 29. The piston 30 is pushed upward, and the same operation as described above is repeated at high speed, so that the piston 30 performs high-speed reciprocating motion, that is, vertical vibration damping. The head plate 31 is screwed onto the tip of the piston 30 with a screw 39.

As shown in FIGS. 10 to 12, the on-off valve 12 consists of an elliptical valve receiver 41 having a valve port 40 and a valve body 42 that opens and closes the valve port 40. The valve receiver 41 is fixed. It is fixed to the upper part of the upper pipe part 11a of the pipe 11, a packing 43 is attached to the lower peripheral edge of the valve port 40, and the valve body 42 is arranged on the lower side of the valve receiver 41. The hinge member 44 and the hinge member 46 at one end of the support frame 45 fixed to the lower surface of the valve body 42 are screwed together with a pin 47, thereby making the valve body 42 openable and closable with respect to the valve port 40. Normally, this valve body 42 is in an open state at the position shown by the dashed line in FIG. The valve element 42 is pressed upward and rotated by the pressurized air and held in the closed position, thereby closing the valve. In addition, instead of performing the closing operation of the valve body 42 by such air pressure, as shown by the two-dot chain line in FIG. A spring member 48 is interposed so that the valve body 42 is normally held in the closed position by the force of the spring, and when sand is introduced from the hopper 10, the weight of the sand resists the force of the spring and opens the valve body 42. You can also do it like this.

When operating the sand pile making device having the structure described above, first, only the drive device 8 is operated while the elevator frame 1 of the device is suspended and supported at an appropriate height from the top of the leader (not shown). The outer tube 3 with the screw 2 is rotated in the feeding direction of the screw 2, and while the lifting operation wire (not shown) is let out to lower the outer tube 3, the outer tube 3 is removed by the drilling action of the outer tube 3. The pipe 3, the middle pipe 5, and the middle pipe 6 with the air hammer 7 are penetrated into the ground. Prior to the penetration of this outer tube 3, so-called point sand (sand plug) is put in the lower end of the outer tube 3 (the part where the screw 4 of the middle tube 5 is located), and when drilling the hole, the inside of the outer tube 3 is removed. to prevent dirt from entering.

After the outer pipe 3 is penetrated into the ground together with the middle pipe 5 and the inner pipe 6 to a predetermined depth as described above, the outer pipe 3
While rotating the inner tube 5 with the screw 4 in the direction opposite to the direction of the insertion, the inner tube 5 with the screw 4 is rotated in the feeding direction of the screw 4, and is inserted into the outer tube 3 from the hopper 10 through the fixed tube 11. Sand is put in, and pressurized air is further supplied from the air supply pipe 13 to the air hammer 7 through the air supply passage 6a of the inner pipe 6 to operate the air hammer. The sand put into the outer tube 3 is compressed by the screw 4 of the middle tube 5 and pushed out from the lower end of the outer tube 3, and an air hammer 7 vibrates vertically at the lower end.
By gradually raising and lowering the elevator frame 1 via a wire for lifting and lowering the machine frame (not shown), the sand compacted by the screw 4 and tamped by the air hammer 7 is removed from the outer tube. 3. Sand piles are gradually formed as they are pushed out from the bottom. In this case, when one sand pile's worth of sand has been poured into the outer tube 3, pressurized air is supplied into the fixed tube 11 through the air supply pipe 14, and when the sand has finished being poured into the outer tube 3, the on-off valve 12 is closes the valve and seals the inside of the fixed tube 11 to increase the air pressure in the internal space from the fixed tube 11 to the outer tube 3, and the increased air pressure presses the sand inside the outer tube 3. It is pushed out from the lower end of the outer tube 3 while being compressed more strongly. As a result, a strong sand pile that is sufficiently consolidated and compacted will be formed.

In the embodiment described above, the screw is provided along the entire length of the outer tube, but this is the most preferred case, and the screw may be provided only at the lower end of the outer tube, and the screw in the middle tube is not implemented. In the example, it is provided only at the lower end of the middle tube, but it may be provided from the lower end to the middle or even over the entire length.

(Effects of the Invention) The sand pile building device of the present invention includes an outer tube having a screw screwed on at least the lower end of the outer periphery, and an inner tube fitted into the outer tube and having a screw screwed on at least the lower end of the outer periphery. The pipes are connected to each other so as to be freely rotatable, and an air hammer is attached to the lower end of the inner pipe, which communicates with the inner pipe with the inside serving as an air supply path, and protrudes from the lower end of the middle pipe. A hopper for feeding sand is connected to the outer pipe via a fixed attachment supported on the elevator frame, and an air supply pipe for operating the air hammer is connected to the upper end of the inner pipe. A pressure air supply pipe is connected to the hopper, and an on-off valve is provided between the fixed pipe and the hopper.When forming a sand pile, the sand put into the outer pipe is pressed by pressurized air. As the sand is compacted by the action and extrusion action of the screw, and tamped by the impact action of the air hammer, the sand can be sufficiently compacted and an extremely strong sand pile can be formed. Since the air hammer itself is not equipped with an exciter, and the air hammer itself is attached to the lower end of the inner pipe and operates underground, it is possible to minimize the generation of noise and vibration during work. Pile construction work can be performed with almost no noise or vibration.

Furthermore, in the sand pile building device of the present invention, the inner pipe drive motor for rotationally driving the inner pipe and the outer pipe drive motor for rotationally driving the outer pipe are connected to fixed pipes at the upper and lower parts of the elevator frame. Since a pair of sand piles are installed at symmetrical positions on both sides, the center of gravity of the sand pile making device is located on the central axis of the device (the axis passing through the centers of the outer, middle, and inner tubes). Therefore, this device can be lifted and lowered in an extremely stable state without shaking or rattling when suspended from the top of the leader with wires, etc., thereby preventing penetration into the ground and its subsequent movement. This makes it easier to pull out the tube, and even if each drive motor is relatively small, the pair of motors on each side can reliably apply stronger rotational torque to each of the inner and outer tubes. can. Furthermore, in the device of the present invention, the large-diameter head provided at the upper end of the inner tube inserted into the middle tube is supported by the upper end of the middle tube so that it can rotate freely, so the support structure of the inner tube is extremely compact. It is simple and does not interfere with the distribution of sand thrown in from the hopper. Furthermore, the fixed pipe is configured with an upper pipe part and a lower pipe part, and a required gap is provided between the lower end of the upper pipe and the upper end of the lower pipe part, and the middle pipe side fixed to the upper end of the middle pipe is fixed to the upper end of the middle pipe. A large gear is inserted airtightly through the gap and protrudes from the outer tube, and is meshed with the output gear of each of the middle tube drive motors, and sand and air are circulated through the large gear on the middle tube side. Since the on-off valve is provided with an opening, the rotational drive for the middle pipe placed inside the fixed pipe, which is in a sealed state when the on-off valve is closed, can be controlled by the pair of both sides placed outside the fixed pipe. This can be done directly by a motor without complicating the structure, and there is no problem with the flow of sand or air in the fixed pipe.

[Brief explanation of the drawing]

FIG. 1 is a partial longitudinal cross-sectional view showing an embodiment of the sand pile building device according to the present invention, FIG. 2 is an enlarged cross-sectional view taken along the line -- in FIG. 1, and FIG. 3 is an enlarged cross-sectional view taken along the line -- in FIG. , FIG. 4 is an enlarged cross-sectional view taken along the - line in FIG. 1, and FIG.
The figure is a - line enlarged sectional view of Figure 1, and Figure 6 is an enlarged cross-sectional view of Figure 1.
7 is a sectional view taken along the - line in FIG. 6, FIG. 8 is a sectional view taken along the - line in FIG. 6, FIG. 9 is a sectional view taken along the - line in FIG. 6, FIG. 10 is a plan view of the valve receiver of the on-off valve shown in FIG. 1, FIG. 11 is a plan view of the valve body, and FIG. 12 is a longitudinal sectional view showing how the on-off valve is installed. 1... Elevator frame, 2... Screw, 3... Outer tube, 4... Screw, 5... Middle tube, 6... Inner tube, 6b... Large diameter head, 7... Air hammer, 8...
...outer tube rotation drive device, 9...middle tube rotation drive device,
10...Hopper for sand charging, 11...Fixed pipe, 1
1a...Upper pipe part, 11b...Lower pipe part, 12...Opening/closing valve, 13...Air hammer operation air supply pipe, 14...Sand pressing air supply pipe, 15...
...Large gear on the outer tube side, 16... Motor for driving the outer tube, 18... Output gear, 19... Large gear on the middle tube side, 19a... Opening, 20... Motor for driving the middle tube, 22... Output gear, 23... Seal ring, 24... Bearing that also serves as a seal, 25... Support member.

Claims (1)

[Claims] 1. An outer tube with a screw threaded on at least the lower end of the outer periphery is rotatably connected to an elevator frame that is suspended vertically along the leader, and the outer tube has a screw threaded on at least the lower end of the outer periphery. A middle pipe with a threaded structure is rotatably inserted and supported, and an inner pipe whose inside is an air supply path is inserted into the middle pipe, and the large-diameter head at the upper end of the inner pipe is rotated relative to the upper end of the middle pipe. An air hammer is attached to the lower end of the inner tube that is freely supported and protrudes from the lower end of the middle tube, and a hopper for introducing sand into the outer tube is connected to the outer tube via a fixed tube supported by the elevator frame. Inside the elevator frame, a pair of inner pipe drive motors are arranged on both sides at symmetrical positions on the upper side, and a pair of outer pipe drive motors on both sides are arranged on the lower side. The fixed pipe is composed of an upper pipe part and a lower pipe part, and a required gap is provided between the lower end of the upper pipe and the upper end of the lower pipe part, and the middle pipe is fixed to the upper end of the middle pipe. The large side gear is passed through the gap airtightly and protrudes from the outer tube, and is meshed with the output gear of each of the middle tube drive motors, and the large gear on the middle tube side is supplied with sand and air. An opening is provided for the circulation, and a large gear on the outer tube side fixed to the upper end of the outer tube is meshed with the output gear of each of the outer tube drive motors, and a sand pressing air supply pipe is connected to the fixed tube. A sand pile construction device that connects a fixed pipe and a hopper and provides an on-off valve between the fixed pipe and the hopper.