JPH0823134B2 - Sand pile building equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sand pile forming apparatus used for a method of forming sand piles in soft ground to improve the soft ground.

[0002]

2. Description of the Related Art A conventional device of this type has a rotary casing having an outer peripheral surface screwed with a screw for excavation, and an upper end connected to a sand supply hopper so as to be fixedly inserted into the rotary casing. It comprises a casing and an inner rod for sand compaction which is inserted into the fixed casing and is movable up and down. While the rotary casing is normally rotated by the rotation driving means, the rotary casing is reversely rotated after it is dug to a predetermined depth in the ground. While pulling out both casings and excavating excavated soil with the screw, sand supplied into the fixed casing from the hopper is discharged from the lower end of the fixed casing, and the inner rod is moved up and down by the vertical drive means. By doing so, sand piles are created in the ground.

[0003]

In the conventional apparatus as described above, the rotating casing is rotated in the forward direction and the screw on the outer peripheral surface thereof is used to excavate the casing to a predetermined depth in the ground, and then the casing is pulled out when the casing is pulled out. Since the soil is discharged by using the screw by reversing the soil, the amount of soil discharged is not sufficient, that is, the amount of soil discharged is smaller than the amount of ground excavation, and therefore the amount of sand filled in the hole is small. As a result, it becomes impossible to form high-quality sand piles, the wall surface of the drill hole is destroyed by the screw when the casing is pulled out, and a large amount of excavated soil is mixed during the discharge and filling of sand from the lower end of the fixed casing to the drill hole. Because of that, we couldn't create good quality sand piles. Further, in the conventional device, the rotation of the rotary casing needs to be switched between forward and reverse when the casing is driven in and when the casing is pulled out, which causes a problem that the operation is complicated and the control system becomes complicated.

In view of the above-mentioned problems in the conventional apparatus, the present invention is capable of sufficiently discharging the soil and strengthening the wall surface of the hole to prevent the mixture of the soil into the hole. It is an object of the present invention to provide a sand pile forming device capable of forming extremely high quality sand piles.

[0005]

In the sand pile forming apparatus according to the present invention, an inner rotating casing having a screw for discharging soil on the outer peripheral surface thereof is provided with a large number of through holes and an outer side having an excavating blade at the lower end. The rotary casing is fitted on the outside, and both rotary casings are interlockingly connected to the rotary drive means so as to be able to rotate in opposite directions, and a fixed casing whose upper end is connected to the sand supply hopper is inserted into the inner rotary casing. An inner rod for sand tamping is vertically movably inserted into the fixed casing, and an upper end portion of the inner rod is interlocked with a vertical drive means.

[0006]

EXAMPLES Examples will be described with reference to the drawings.
FIG. 1 shows the entire sand pile forming apparatus according to the present invention,
In this figure, reference numeral 1 designates a machine frame suspended from the top of a leader (not shown) via a wire for raising and lowering operation (not shown) and vertically supported along a guide rail (not shown) of the leader. A sand storage tank 2 is provided on the upper part of the machine frame 1, and a sand supply hopper 3 is provided on a side portion of the tank 2. 4 is a screw for earth removal 5 on the outer peripheral surface
And a cylindrical outer rotary casing 6 fitted onto the inner rotary casing 4, both rotary casings 4 and 6 are rotatably attached to the lower portion of the machine casing 1. A pair of rotation driving means 7, which are both suspended and provided on the lower portion of the machine frame 1,
7 are interlockingly connected to each other so as to be rotatable in opposite directions. A large number of through holes 8 are formed in the outer rotary casing 6 over the entire area, and a plurality of excavating blades 9 are integrally projecting downward and inward at the lower end of the casing 6.

A cylindrical fixed casing 10 having a slightly smaller diameter is concentrically inserted into the inner rotary casing 4 so that the upper end of the fixed casing 10 communicates with the bottom wall 2a of the sand storage tank 2. A hollow inner rod 1 for sand compaction is connected in the fixed casing 10.
1 is vertically movably inserted, and the upper end of the inner rod 11 is inserted through the sand storage tank 2 and is interlockingly connected to the inner rod up-and-down driving means 12 installed at the top of the machine frame 1. In addition, an electric vibroflot 13 for sand compaction is provided at a lower end portion of the inner rod 11, and an electric wire for supplying power to the electric motor of the vibroflot 13 is not shown.
It is inserted into the inner rod 11 and extends to the outside from a required portion on the upper part thereof.

The pair of rotary drive means 7, 7 are arranged symmetrically on both sides of the outer rotary casing 6, and the output shaft 1 of the electric motor 14 in each rotary drive means 7.
The drive gear 16 fixed to the base end side of 5 is meshed with the driven gear 17 fixed to the upper end outer peripheral surface of the inner rotary casing 4 via the intermediate transmission gear 18, and is connected to the tip end side of the output shaft 15. The fixed drive gear 19 meshes with the driven gear 20 fixed to the outer peripheral surface of the upper end of the outer rotary casing 6, and the rotation of the output shaft 15 caused by the operation of the electric motor 14 causes the inner rotary casing 4 and the outer rotary casing 6 to move. It is designed to rotate in opposite directions. Further, a top plate 21 is provided so as to project at a lower proximity position of the driven gear 17 at an upper end portion of the inner rotary casing 4, and the outward flange 22 provided so as to project at the top ends of the top plate 21 and the outer rotation casing 6. An annular soil discharge port 23 is formed between and.

The inner rod up-and-down driving means 12 is composed of a pair of well-known air spring devices 24 and 24 on both sides. The upper half of each air spring device 24 is a lowering air spring 24a and the lower half is an upper part. The upper end of the inner rod 11 is connected to the movable frame 25 provided between the air springs 24a and 24b, and the movable frame 25 is slidable to the pair of guide columns 26, 26 on both sides. The compressed air from the air compressor is alternately supplied to the lower moving air springs 24a and the upper moving air springs 24b, whereby the air springs 24a and 24b expand and contract alternately. The inner rod 11 moves up and down with a predetermined stroke.

A partition wall portion 2b is provided in the sand storage tank 2 on the side closer to the bottom wall portion 2a. Sand partitioning openings 27, 27 are formed in the partition wall portion 2b at symmetrical positions on both sides of the partition wall portion 2b. An opening / closing valve 28 is provided at the opening 27, and the partition wall 2
An air nozzle 30 for supplying pressurized air to the space 29 formed between b and the bottom wall portion 2a is inserted into the space.
It should be noted that, in the sand storage tank 2, at least one sand of constructed sand pile is temporarily stored above the partition wall 2b in a state where each of the on-off valves 28 is closed. There is. Although not shown, each on-off valve 28 is interlockingly connected with a valve opening / closing driving means such as a cylinder, and is opened / closed by this driving means.

Next, a method of using the sand pile forming apparatus having the above-described structure will be described. First, the rotation driving means 7 is operated while the apparatus frame 1 is suspended and supported at a proper height from the top of the leader. Then, the outer rotating casing 6 is rotated in the normal direction and the inner rotating casing 4 is rotated in the reverse direction, and the wire for lifting and lowering operation of the machine frame 1 is fed out and penetrates into the ground. When the casing penetrates, the entire casing 4, 6, 10 is excavated in the ground while excavating the ground by the excavation action of the excavation blade 9 at the lower end of the outer rotating casing 6 together with the weight of the entire apparatus and the normal rotating action of the outer rotating casing 6. While being buried, the excavated soil is pushed up from between the inner and outer rotary casings 4 and 6 by the soil discharging screw of the inner rotary casing 6, and a part of the excavated soil is exposed to the outside from the through hole 8 of the outer rotary casing 6. The excavated soil that has been pushed out and pressed against the wall surface of the digging hole and not discharged through the through hole 8 is pushed up as it is and discharged to the ground through the discharge outlet 23 at the upper ends of both the inner and outer rotary casings 4 and 6.

Further, during the penetration of the casing, in the case of the outer rotating casing 6 having no screw, if it is normal, a considerably large earth pressure is applied to the outer peripheral surface from around the ground to rotate due to the pressure friction resistance. Although the penetrating action is hindered, the outer rotary casing 6 is provided with a large number of through holes 8 over its entire area, so that the through holes 8 reduce the pressure friction resistance. As a result, the outer rotary casing 6 rotates smoothly without any difference from the screw-equipped rotary casing and penetrates into the ground. Further, in this case, the outer rotating casing 6 having no screw rotates while being pressed against the wall surface of the digging hole, and the excavated soil is pushed out from each through hole 8 of the casing 6 by the soil discharging screw 5. Since the wall surface of the hole is pressed against the wall surface of the hole, the wall surface of the hole becomes strong and does not collapse unlike the conventional device.

When the outer rotary casing 6 reaches a predetermined depth in the ground, sand is supplied from the sand supply hopper 3 into the sand storage tank 2 whose sand inlet 27 is closed. After a predetermined amount of sand is supplied (for example, the amount of sand for one sand pile), the opening / closing valves 28 are operated to open the sand in the tank 2 from the sand inlet 27 through the space 29 to the fixed casing. Put in 10. The upper surface of the thrown-in sand is located at the intermediate portion of the space 29 in the state where the throwing-in of the sand is completed, and at this time, the on-off valve 28 is closed to start the supply of the pressure air from the air nozzle 30. The internal pressure of the space 29 is increased.

When the inner pressure of the space 29 reaches a predetermined pressure, the inner rod up-and-down drive means 12 is operated to operate the inner rod 11.
Is moved up and down, and further the vibro flot 13 at the tip of the inner rod 11 is operated. The rotation driving means 7 may be continuously operated after the casing penetrates to rotate the inner and outer rotating casings 4 and 6 as it is, or may be stopped when the casing penetrates. In such a state, when the inner and outer rotary casings 4 and 6 are pulled out while winding up and down the operation wire of the machine frame 1, the sand in the fixed casing 10 causes the inner rod 11 to move up and down and vibrates. While being sufficiently compacted by the vibrating action of the Loflot 13, while being pressed from above the pressure on the side of the space portion 29, it is effectively pushed out from the lower end of the fixed casing 10 and is solid sand pile that is compacted in the ground. Will be formed.

[0015]

According to the sand pile forming apparatus of the present invention, when the casing penetrates, the rotation driving means is operated to rotate the outer rotating casing in the normal direction and the inner rotating casing in the reverse direction, while the inner and outer rotating casings are ground. It penetrates inside. When the casing penetrates, the ground is excavated by the self-weight of the entire device and the normal rotation action of the outer rotary casing, and the excavation action of the excavating blade at the lower end of the outer rotary casing excavates the soil. While being pulled up from between the two rotating casings by the screw for earth removal of the inner rotating casing, a part of it is pushed out from the through hole of the outer rotating casing and is crimped to the wall surface of the pit,
The excavated soil that has not been discharged from the through holes is pushed up as it is and discharged from the upper ends of the outer rotary casings to the ground. Therefore, most of the excavated soil is effectively discharged when the casing penetrates.

During the penetration of the casing, in the case of the outer rotating casing having no screw, a considerably large earth pressure is normally applied to the outer peripheral surface of the outer peripheral surface from the ground periphery, and the rotational penetration action is caused by the pressure frictional resistance. Although hindered, the outer rotary casing has a large number of through-holes formed throughout its entire area, and therefore the through-holes reduce the pressure frictional resistance, whereby the outer rotary casing is It rotates smoothly like a rotating casing with screws and penetrates into the ground. Also, during casing penetration, the outer rotating casing, which does not have a screw, rotates while pressing against the wall surface of the hole, and the excavated soil is pushed out from each through hole of the casing by the screw for soil removal to the wall surface of the hole. Since it is crimped, the wall surface of the pit becomes a solid wall and does not collapse as in the case of conventional equipment, and when excavating the casing, the excavated soil enters the pit or the sand discharged from the fixed casing. It is less likely to get mixed in.

After the outer rotary casing reaches a predetermined depth in the ground, the inner rod up-and-down drive means is operated to move the inner rod up and down. Further, the rotation drive means may be continuously operated from the time of penetration of the casing to drive the inner and outer rotating casings to rotate in the same direction as the time of penetration, or may be stopped at the time of completion of penetration of the casing. In such a state, when the inner and outer rotary casings are pulled out, the sand supplied from the sand supply hopper into the fixed casing is sufficiently tampered by the tamping action of the vertical movement of the inner rod, and from the lower end of the fixed casing. It is pushed out and discharged into the hole. As a result, high-quality and high-density sand piles are formed. Further, when the casing is pulled out, it is not necessary to reverse the rotating casing as in the conventional device, so that the operation is easy and the control system can be simple.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a sand pile building device showing an embodiment of the present invention.

[Explanation of symbols]

 1 Equipment Machine Frame 2 Sand Storage Tank 3 Sand Supply Hopper 4 Inner Rotating Casing 5 Excretion Screw 6 Outer Rotating Casing 7 Rotation Driving Means 8 Through Hole 9 Excavation Blade 10 Fixed Casing 11 Inner Rod for Sand Sanding 12 Inner Rod Top and Bottom Drive means

Claims (1)

[Claims] 1. An outer rotary casing having a large number of through holes and a drilling blade at its lower end is fitted onto an inner rotary casing having an earth discharging screw on its outer peripheral surface, and both rotary casings are rotated. A fixed casing, which is rotatably coupled to the driving means so as to be rotatable in opposite directions, and has an upper end communicating with and connected to a sand supplying hopper, is inserted into the inner rotating casing, and an inner rod for sand tamping is inserted into the fixed casing. A sand pile forming device, which is vertically movably inserted, and whose upper end portion is interlockingly connected to a vertical drive means.