JP4762205B2 - Coupling for pile rotation transmission in emergency - Google Patents

Description

  The invention of the present application is an emergency for embedding by laying the hollow pile when it is difficult to embed the hollow pile due to peripheral surface frictional resistance, etc. The present invention relates to a pile rotation transmission coupling.

  Conventionally, a drilling screw rod is inserted into a hollow pile, and by rotating the drilling screw rod, a hollow pile is press-fitted into the drilling hole while pre-digging the ground at the lower end of the hollow pile with a drilling head at the lower end of the rod, The excavated sediment is widely carried out in the hollow pile excavation method in which the screw rod transports the hollow pile upward and discharges it.

  However, in recent years, hollow piles to be buried have been required to have large diameters to increase the bearing capacity. The circumferential frictional resistance will increase. As a result, in hollow pile burial construction, it is often difficult to bury the hollow pile immediately before the completion of the burial, especially when the hollow pile approaches the supporting ground.

  Conventionally, as a countermeasure, first, a pile rotation transmission coupling is prepared. The coupling is a cap-like one that can be fitted on the upper end of the hollow pile, and the upper end of the hollow pile is placed on the peripheral wall of the cap. A locking projection protruding from the outer peripheral surface of the part and a locked groove that can be freely engaged and disengaged are formed, and an upper joint is projected from the center of the upper surface of the cap.

  Therefore, when it becomes difficult to embed a hollow pile, first, the excavation screw rod is lifted to the ground leaving the hollow pile, and then the excavation screw rod is detached from the joint at the required position, and the upper end having the joint at the lower end. Separated into a rod part and a lower rod part, the pile rotation transmission coupling is connected to the joint at the lower end of the upper rod part by an upper joint, and then the coupling is fitted to the upper end part of the hollow pile At the same time, the locking projection and the locked groove are engaged and connected so as to transmit rotation. By giving the rotation of the upper rod part connected in this way to the hollow pile through the coupling, an emergency measure is taken to reduce the peripheral frictional resistance received by the hollow pile and overcome the difficulty of embedding the hollow pile. It was done.

  However, the conventional emergency measures using the pile rotation transmission coupling as described above waste time in the work of raising the overall length of the drilling screw rod and the work of separately storing the lower rod portion of the screw rod. Along with this, there is a drawback that the hollow pile is crimped to the surrounding ground due to the tightening of the ground around the pile. Furthermore, since only the upper rod part is connected to the hollow pile except for the lower rod part of the excavation screw rod, there is a problem that the press-fit load applied to the hollow pile is reduced.

  This invention makes it a subject to provide the coupling for pile rotation transmission which can perform the connection operation | work of a coupling in a short time, and can apply a required press-fit load to a hollow pile.

As means for solving the above problems, the present invention
It is a cap-like body that is freely detachable from the upper end of the hollow pile,
The cap-like body is provided with a locking portion detachably engaged with the locking portion provided at the upper end of the hollow pile, and the hollow pile is removed from the cap-shaped body when the locking portion and the locked portion are engaged. It is in a positional relationship that enables rotation transmission to
The upper joint is vertically projected at the center of the outer top surface of the circular top plate of the cap-like body, and the lower joint is projected on the axial extension of the upper joint at the center of the inner bottom surface of the circular top plate.
A coupling for pile rotation transmission is proposed.

  According to the emergency pile rotation transmission coupling of the present invention, when it is difficult to embed the hollow pile due to the peripheral frictional resistance, the screw rod is moved into the hollow pile without lifting the excavating screw rod to the ground. The lower rod portion and the upper rod portion are separated from the joint, and the pile rotation transmission coupling of the present invention is positioned between the upper rod portion and the lower rod portion, and the upper joint is connected to the upper rod portion. The connection to the part can be completed in a short time by connecting the lower joint to the lower rod part, and accordingly, the crimping of the hollow pile with the surrounding ground can be substantially prevented. Furthermore, the weight of the entire length of the excavation screw rod can be applied to the hollow pile as a press-fit load, whereby the hollow pile embedding after resumption can be performed more easily than before.

  Embodiments of the present invention will be described in detail below with reference to the drawings. First, on the outer peripheral surface of the upper end portion of the hollow pile (P), four locking protrusions (d).

  As shown in FIGS. 1 and 2, the pile rotation transmission coupling (1) of the present invention is fitted in the upper end portion of the hollow pile (P) and is a short cylindrical cap-like shape with a freely openable lower end, The peripheral wall (2) is provided with a locking protrusion (d) of the hollow pile (P) and a locked groove (3) to be engaged and disengaged, and the locked groove (3) is one of them. When viewed, the groove (3a) cut in the bus bar direction from the peripheral wall (2), and then the groove (3b) cut in the counterclockwise direction in the circumferential direction is formed into a substantially L shape, and the bus bar groove (3a) A cover plate (4) is fixed to the outer surface of the cut opening.

  The coupling (1) is fitted on the upper end of the hollow pile (P), and the locking protrusion (d) of the hollow pile engages with the bus-line direction groove (3a), and then with the circumferential groove (3b). In this case, the coupling (1) is engaged with the hollow pile (P) in a retaining state and capable of transmitting rotation.

  An upper male joint (6) that can be connected to a female joint of male and female joints of a drilling screw rod described later is vertically projected at the center of the upper surface of the circular top plate (5) of the cap-shaped body as described above. In addition, a lower female joint (7) connectable with the male joint of the drilling screw rod is provided on the inner lower surface center of the circular top plate (5) on the axial extension of the upper male joint (6). .

  Next, an example of use of the above-described pile rotation transmission coupling (1) will be described. In FIG. 3, a drilling screw rod (S) has a unit length screw rod connected to a required length via a male / female joint (j)... And a drilling head (h) provided at the lower end. The screw rod (S) is connected to the output shaft of the rotary drive device supported by the mast so as to be movable up and down by a wire rope.

  As shown in FIG. 3 (a), the excavation screw rod (S) is inserted into the hollow pile (P), and the hollow pile (P) is buried by the medium excavation method by the rotation of the excavation screw rod (S). . When it is difficult to embed the hollow pile (P) due to the peripheral frictional resistance, the drilling screw rod (S) is first lifted up appropriately as shown in (b). Then, the nearest joint (j) located in the hollow pile (P) is exposed on the hollow pile (P).

  Next, in a state where the lower rod (Sa) below the exposed joint (j) is held by appropriate means, the male / female joint of the joint (j) is disengaged, and FIG. In this way, the lower rod portion (Sa) having the male joint (ja) at the upper end and the upper rod portion (Sb) having the female joint (jb) at the lower end are separated and the upper rod portion (Sb) is appropriately raised. And a space between the lower rod part (Sa).

  Next, the upper male joint (6) of the pile rotation transmission coupling (1) is connected to the female joint (jb) at the lower end of the upper rod part (Sb) as shown in FIG. (Sb) is lowered and the lower female joint (7) of the coupling (1) is connected to the male joint (ja) at the upper end of the lower rod part (Sa).

  After releasing the holding of the lower rod portion (Sa), the excavating screw rod (S) is slightly lowered, and the bus-direction grooves (3a) of the locked grooves (3) of the coupling (1). Are respectively engaged with the locking protrusions (d) of the hollow pile (P), and then the drilling screw rod (S) is rotated in the direction of the arrow in FIG. (3b) are engaged with the locking projections (d), respectively.

  If the drilling screw rod (S) is rotated, the rotation is transmitted to the hollow pile (P) through the coupling (1), and the weight of the entire length of the drilling screw rod (S) is press-fitted into the hollow pile (P). Applied as a load, the hollow pile (P) thus cuts the peripheral frictional resistance by its rotation and a heavy press-fitting load and resumes the press-fitting.

It is a partially notched front view of the coupling for pile rotation transmission by this invention. It is a bottom view same as the above. (A) It is a general | schematic longitudinal cross-sectional view of the state where the hollow pile embedding in the usage example of the coupling for pile rotation transmission reached difficulty. (B) It is an approximate line longitudinal cross-sectional view in the state where the nearest joint is exposed. (C) It is an approximate line longitudinal cross-sectional view of the state which isolate | separated the drilling screw rod. (D) It is an approximate line longitudinal cross-sectional view of the state which connected the coupling for pile rotation transmission to the upper rod part. (E) It is an approximate line longitudinal cross-sectional view of the state which engaged the coupling for pile rotation transmission with the hollow pile upper end.

Explanation of symbols

1 Pile rotation transmission coupling 3 Locked groove 5 Circular top plate 6 Upper joint 7 Lower joint P Hollow pile d Locking protrusion

Claims (1)

It is a cap-like body that is freely detachable from the upper end of the hollow pile,
The cap-like body is provided with a locking portion detachably engaged with the locking portion provided at the upper end of the hollow pile, and the hollow pile is removed from the cap-shaped body when the locking portion and the locked portion are engaged. It is in a positional relationship that enables rotation transmission to
The upper joint is vertically projected at the center of the outer top surface of the circular top plate of the cap-like body, and the lower joint is projected on the axial extension of the upper joint at the center of the inner bottom surface of the circular top plate.
Pile rotation transmission coupling.

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