JP2816740B2 - Cast-in-place pile forming machine - Google Patents

Description

The present invention relates to a cast-in-place pile builder for foundation work.

[Prior art] Conventionally, as a cast-in-place pile method, a hole is previously drilled in the ground, a bag is inserted into the hole, and then a hydraulic slurry is injected into the bag to form a pile. Have been done.

[Problems to be Solved by the Invention] However, the above method has the following problems.

Since the drilling step and the step of pushing / inserting the bag are required, the steps are complicated and require a long time.

When the ground is sandy ground, it is often difficult to insert the bag body because the hole wall is likely to collapse, and the bag body stays high when inserted.

When the bag is inserted, the bag is often damaged by friction with the hole wall or the like.

The shape of the pile to be formed is easily affected by the strength of the ground, and the reliability is poor.

Therefore, in order to solve such a problem, the bag is attached to the inside of the hollow tube, a hole is drilled to a predetermined depth by the hollow tube, and then only the hollow tube is pulled up and the hydraulic fluid is introduced into the bag. There has been proposed a construction method in which a slurry is press-fitted (for example, JP-A-64-36821).

An object of the present invention is to provide a cast-in-place pile forming machine suitable for performing such a construction method.

[Means for Solving the Problems] In order to achieve the above object, a cast-in-place pile builder according to the present invention includes a guide frame, a drill head slidably mounted on the guide frame, and having a motor. A base end is attached to the drill head, an auger blade is formed on the outer periphery near the lower end, and a notch is provided at the end, and an outer tube rotated by the motor and a base end penetrate the drill head. Then, a pair of guide square members facing each other in the axial direction are disposed on the inner periphery and loosely fitted in the outer tube, and the inner tube having a notch at the end thereof is sandwiched between the inner tube and the outer bag. A pair of fixing plates, which are attached to the tips and can be engaged with the notches of the inner and outer tubes while being held therebetween, and an upper end of the bag are detachably held, and are axially attached to a guide square member in the inner tube. A holder slidably engaging; A winch for suspending the holder with a wire through a sarkan;
An inner tube pushing device mounted on the drill head and pushing the inner tube toward the outer tube in a distal direction, and a feeding device for moving the drill head up and down along the guide frame. .

[Operation] When the bag is inserted into the inner tube and the holding device holding the upper portion of the bag is pulled by the winch wire, the fixing plate is engaged with the notch at the tip of the inner and outer tubes. When the outer tube is rotated, the torque of the outer tube is transmitted to the inner tube via the fixing plate, and the inner tube rotates together with the outer tube.

Further, when the inner tube pushing device is operated to push the inner tube in the distal direction, the fixing plate is detached from the notch provided at the distal end of the outer tube, so that the inner tube is free with respect to the outer tube.

Furthermore, in the bag body mounted in the inner tube, the retainer holding the upper end is engaged with the guide square in the inner tube, and the fixing plate holding the lower end is engaged with the notch at the end of the inner tube. The bag does not rotate with respect to the inner tube and does not twist.

[Example] In FIGS. 1a and 2, reference numeral 1 denotes a base machine, 2 denotes a guide frame, and a drill head 3 is mounted on the guide frame 2 so as to be movable up and down. Are arranged side by side so as to be vertically movable.

The drill head 3 is provided with an oil motor 3a for rotating the outer tube 4.

An auger blade 5 is formed at a predetermined length near the lower end of the outer tube 4, and a pair of notches 6 are provided at axially symmetric positions on the end surface (FIGS. 3a and 3b). .

As shown in FIGS. 3a and 3b, an inner tube 8 having a pair of notches 7 similar to the outer tube 4 at its distal end surface is loosely fitted inside the outer tube 4, as shown in FIGS. The end penetrates the drill head 3. A ring body 9 having a concave portion 9a with which a cam follower 19 of an inner tube pushing device 20 described later is engaged is attached to the outer periphery of the upper end of the base end portion, and a guide square member is provided on the inner periphery.
10 and 10 (Figs. 3a and 4b) are mounted in the axial direction.

The position where the guide square member 10 is provided is the same as the position where the notch 7 is provided on the inner wall peripheral surface of the inner tube 8.

Further, the role of this guide square is to guide a holder 24 for holding the upper end of the bag body 40 described later, and to fix the lower end to the fixing plate.
The bag body 40 and the inner tube 8 engaged with 21 are rotated integrally, so that the bag body 40 is not twisted. Further, when the bag body 40 is pushed out by the inner tube pushing device 20, the bag body 40 is Even when the outer pipe 4 and the inner pipe 8 rise after being fixed in the soil, the bag body 40 does not twist.

FIG. 10 shows a feeding device 11, in which a roller chain 15 is engaged with a sprocket 14 connected to an oil motor 12 provided at the upper end of the guide frame 2 via a speed reducer 13. A roller chain 15 is stretched between the sprocket 14a attached to the lower end of the guide frame 2 and the sprocket 14a. Then, both ends of the roller chain 15 are fixed to the drill head 3 as shown in FIG.
Figure).

Therefore, when the oil motor 12 is driven, the power is transmitted through the sprocket 14 → the roller chain 15, and the drill head 3 moves up and down. In this example, the oil motor 12 has particularly preferable characteristics in that the torque is large even at a low speed and the impact resistance is high, but another motor may be used. Further, transmission means for converting the power by the motor into vertical movement and transmitting the power to the head is used as a feeding mechanism fixed to the head, and as other transmission means such as a wire or a belt in addition to the sprocket and the roller chain. Is also good. However, a combination of a sprocket and a roller chain is particularly preferable because there is no slip or extension in power transmission.

In FIGS. 8 and 9, reference numeral 20 denotes an inner tube pushing device which is mounted on the upper portion of the drill head 3.

That is, reference numeral 16 denotes a bifurcated shifter fork, the base end of which is pivotally connected to a cylinder 18 by a pin 17, and a cam follower 19 attached to each of the opposing surfaces at the end thereof has a recess 9a at the upper end of the inner tube 8. Is engaged. The operation of the cylinder 18 causes the shifter fork 16 to rotate in the vertical direction, so that only the inner pipe 8 can be pushed downward.

3a and 4a, reference numeral 21 denotes a pair of fixing plates, which are set by holding the lower end of the bag body 40 with bolts 22 during excavation and engaging with the notches 6, 7 at the inner and outer pipe ends. Is what you do. Reference numeral 23 denotes a semicircular closing plate formed in each fixing plate 21 in a horizontal direction, which prevents earth and sand from entering the inner pipe 8 during excavation.

5 to 7, reference numeral 24 denotes a holder for locking the upper end of the bag body 40, and a clip 27 having an upper hole 25 and a lower hole 26.
A clip bar 30 integrally formed with an engaging portion 28 that engages with the upper hole 25 and a plate 29 wider than the engaging portion 28;
It consists of a plate 29 and a bar retainer 31 of the same shape,
As shown in FIG. 5, a clip bar 30 and a bar retainer 31 integrated with bolts are attached to the upper hole 25 of the clip 27 so as to be slidable up and down. Hard bottoms 25a and 30a made of wear-resistant metal are provided on the bottom surface of the upper hole 25 of the clip 27 and the lower surface of the clip bar 30, respectively.

The upper end of the bag 40 is locked to the holder 24 as shown in FIG. That is, after the upper end of the bag resistance 40 is first inserted into the lower hole 26 of the clip 27, it is passed above the clip bar 30 of the upper hole 25, then folded downward, and then passed under the lifted clip bars 30, 31; Thus, when the bag body 40 is pulled downward, the clip bars 30, 31 are pressed downward by the weight of the clip bars 30, 31, and the upper end of the bag body 40 is sandwiched between the hard overlays 25a and 30a. It is what you hold. The clip 27 is rotatably suspended via a sulcan 33 at the tip of a wire 32 fed from a winch 35 (FIG. 1). The sarkan (monkey ring) 33 has a structure in which a metal ring rotates freely. For example, as shown in FIG. 11, the upper and lower rings 33a and 33b rotate independently and freely, respectively. The structure is such that rotation from (or below) is not transmitted downward (or above).

As a material of the bag body 30, a fiber, a plastic film, a metal film, or the like is preferable.

Hereinafter, a pile forming method using this cast-in-place pile forming machine will be described. First, a pair of fixing plates 21 is attached to the lower end of the bag body 40 with bolts 22 on the ground near the outer tube 4.

Next, the wire 32 is drawn out from the winch 35 and the sarkan 33 is attached to the lower end of the wire 32 shown in FIG. 7 (the clip 27 is not attached). Then, the holding tool 24 is attached to the sarkan 33, and the upper end of the bag body 40 is locked to the holding tool 24 as shown in FIG.

Next, the holding tool 24 is held at the lower end of the inner tube 8 by the guide square material 10.
(FIGS. 3a and 4b), the wire 32 is wound up by the winch 35, the bag body 40 is drawn into the inner tube 8, and the upper end surface of the fixing plate 21 is moved as shown in FIGS. 3a and 3b. Are engaged with the notches 7, 6 of the inner and outer tubes 8, 4, respectively. In addition, wire 32
Is applied with tension until the end of excavation, and the bag body 40 and the fixing plate 21 are pulled upward.

Then, the oil motor 3a of the drill head 3 is driven to rotate the outer pipe 4, and at the same time, the oil motor 12 of the feeding device 11 (FIG. 10) is driven to feed the drill head 3 downward (1b). Figure).

When the oil motor 12 is driven, the roller chain 15 is pulled via the sprocket 14, so that the drill head 3 (FIG. 8) attached thereto moves along the guide frame 2, so that the drill head 3 is fed downward or Raised upward.

Accordingly, the inner and outer pipes 8, 4 and the fixing plate 21 rotate and feed together and excavate to a predetermined depth.

In the above case, the outer tube 4 is rotated by the drill head 3, and the torque of the outer tube 4 is transmitted in the order of the notch 6 at the lower end of the outer tube → the fixing plate 21 → the notch 7 at the lower end of the inner tube. It rotates simultaneously with the outer tube 4.

In addition, the holder 24 at the upper end of the bag 40 is
As a result, the bag 40 also rotates integrally and its twisting is prevented.

Further, since the wire 32 is connected to the holder 24 without being twisted via the sarkan 33, the wire 32 is not twisted.

Next, the rotation / feeding is stopped, and the cylinder 18 of the inner pipe pushing device 20 is operated to rotate the shifter fork 16 downward to push the inner pipe 8 downward. As a result, the fixing plate 21
Is pushed out into the soil and fixed, so that the bag body 40 is also fixed, and the engagement between the fixing plate 21 and the notch 6 of the outer tube 4 is released.

Next, when the outer tube 4 is retracted (upward) while rotating in the reverse direction, the engagement between the outer tube 4 and the fixing plate 21 is released as described above, so that the inner tube 8 is not rotated and is moved together with the outer tube 4. To rise. At this time, the bag 40 is set in the soil without being twisted because the guide squares 10 are present in the inner tube 8 of the bag 40.

When the retreat of the inner and outer tubes 8, 4 is completed, the holder 24 also comes off the inner tube 8, so the holder 24 is removed from the upper end of the bag 40, and a hydraulic slurry such as mortar is injected from the upper end opening of the bag 40. Pile.

[Effects of the Invention] As described above, according to the present invention, since drilling and insertion of the bag are performed in one step, not only is the construction simple and quick, but also the collapse of the hole wall is prevented. In addition, since the bag does not stay at a high level or is not damaged, and the pile to be formed can be reliably formed in a predetermined shape without being affected by the strength of the ground, reliability is improved.

Further, according to the present invention, the fixing plate in which the lower portion of the bag is engaged in the inner tube is attached to the lower end of the outer tube so as to be engaged with the notch, and the upper portion of the bag is detachable with the holder. The holding tool is made non-rotatable within the inner tube, and is allowed to move up and down in the axial direction inside the inner tube, and the holding tool is hung on a wire via a sulkan and vertically moved with a winch. As a result, the bag is not damaged at all, the bag is not twisted in the inner tube, and the outer tube and the inner tube are left in the hole. When the bag is pulled up, there is no twist in the bag. As described above, according to the device of the present invention, not only is the pressing operation of the bag body simple and quick, but also the twist of the inserted bag body is eliminated,
Since the injection of the hydraulic slurry after pulling up the inner pipe becomes quicker and the injection pressure can be increased,
The swelling of the bag is sufficient, and the pile and the hole wall adhere to each other, so that the reliability of the pile is improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1a is a side view of a cast-in-place pile forming machine showing an embodiment of the present invention, FIG. 1b is a partial view thereof, FIG. 2 is a front view thereof, FIG.
The figure is an enlarged vertical sectional view of the drill head and the inner and outer pipes driven by it. Fig. 3b is the same, a partial view of the sectional view, Fig. 4a is the bottom view of Fig. 3a, and Fig. 4b is Fig. 3a. 5 is a front view of the holder, FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 5, FIG. 7 is a longitudinal sectional view showing a use state of the holder, FIG. The figure is an enlarged side view of the part of the drill head, FIG.
FIG. 10 is an enlarged side view of the feeding device, partially broken away, and FIG. 11 is a perspective view showing an example of a sarkan. 1 ... Base machine, 2 ... Guide frame, 3 ... Drill head, 3a ... Motor, 4 ... Outer tube, 5 ... Auger blade, 6,7 ... Notch, 8 ... Inner tube, 10 ... … Guide square, 11… Feeding device, 20 …… Inner tube pushing device, 21 …… Fixing plate, 24 …… Holder, 32 …… Wire, 33 …… Sarkan, 35 …… Winch, 40 …… Bag body.

──────────────────────────────────────────────────続 き Continued on the front page (72) Koji Suzuki, Inventor 1-1-11-9-201 Nakaochiai, Shinjuku-ku, Tokyo (58) Field surveyed (Int.Cl. ⁶ , DB name) E02D 5/38 E02D 7 / 00

Claims (1)

(57) [Claims] 1. A guide frame, a drill head slidably mounted on the guide frame and equipped with a motor, a base end mounted on the drill head, and an auger blade formed on an outer periphery near a lower distal end. And a notch at the distal end, an outer tube rotated by the motor, and a pair of base ends penetrating through the drill head and loosely fitted into the outer tube, and a pair of axially opposed inner circumferential portions. A guide square member is disposed, and the inner tube having a notch at the tip is attached to the tip of the bag by holding the bag and engaged with the notch of the inner and outer tubes while holding the bag. A pair of fixing plates capable of being held, a holder for detachably holding the upper end of the bag body and slidably engaging the guide square in the inner tube in the axial direction; and connecting the holder with a wire via a sulcan. The winch to be suspended and the drill An inner tube pushing device mounted on a drill head and pushing the inner tube toward the outer tube in a distal direction, and a feeding device for moving the drill head up and down along the guide frame. Pile making machine.