JP2865459B2 - Chuck structure for hammer drop - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp for lifting a hammer used in a so-called weight drop compaction method for dropping a heavy hammer on a soft ground having a weak ground support to improve the ground. The present invention relates to a chuck structure composed of a hammer receiving object held by a hammer.

[0002]

2. Description of the Related Art The weight drop compaction method described above holds an extremely heavy hammer by a clamp attached to the tip of a wire such as a crane, lifts the hammer, and drops it from a high place. The ground is compacted around the impact point of the ground hit by the hammer and in the depth direction. And in order to perform the work of dropping the hammer efficiently and repeatedly from a predetermined height,
The clamp is usually opened and closed by a hydraulic cylinder. However, the conventional clamp has drawbacks in that it cannot be smoothly opened and closed due to the large weight of the hammer, and that the hammer does not drop horizontally.

[0003]

According to the present invention, as a result of various studies, it has been found that a chuck having a clamp capable of dropping a hammer smoothly and horizontally smoothly and a hammer receiving object held by the clamp is provided. Provides structure.

That is, the present invention relates to a hammer dropping chuck structure comprising a holding clamp which is lifted by a crane or the like and which can be opened and closed, and a hammer receiving object which is held by the clamp. It consists of a metal support that supports the universal pin in parallel with each other, and a clamp that fixes two parallel hammer support pins at the lower end that respectively contact the lower end of the rotatable pin. By providing a contact plate which is in contact with a side surface and is movable inward at a lower portion of the clamp, an opening interval between the support pins can be adjusted.

[0005]

Next, an embodiment of the present invention will be described.

As shown in FIGS. 1 and 2, the following metal receiving object (2) is fixed to the upper end surface of the hammer (1). That is, two sets of opposing perforations are provided on the upper part of two parallel vertical steel plates (3) (3), and an oilless metal (4) is fitted into these perforations,
A pin is inserted between these opposing oilless metals (4).
(5) The (5) is rotatably supported, and a plurality of steel plates are integrally fixed for reinforcement. The oilless metal (4) allows the pins (5) and (5) to rotate freely, so that the hammer (1) can be smoothly separated when the hammer is separated as described below. More oilless metal
(4) prevents wear of the rotatable pin (5) and the steel plate (3). In addition, this receiving object (2) was fixed to the upper surface of the hammer (1) with bolts (6).

Further, as shown in FIG. 3, the clamp has a hydraulic cylinder (7) at the center of both clamp arms (9) (9) so that the clamp arm (8) can be moved around the suspension shaft (8) at the upper end. 9) (9)
The lower end side of the clamp arm (9) (9)
Support pins (10) and (10) for holding the pins (5) and (5) of the metal receiving object (2) were fixed to the lower end of the metal holder (2) obliquely upward inside the clamp opening. In addition, compression springs (11) and (11) are provided above these support pins (10) and (10), and adjustment screws (12) and (12)
Then, the backing plates (13) (13) which can be moved in the lateral direction were attached.
In the drawing, (14) is a suspended wire rope provided with a hook for lifting the clamp (15) with a crane or the like.

[0008] The clamp (15) and the hammer receiver (2) are used in combination as follows. That is, FIG.
As shown in the figure, the support pins (10) and (10) at the lower end of the clamp come into contact with the lower end surfaces of the rotatable pins (5) and (5) of the metal receiving object (2), respectively, and are received by the clamp (15). Hold the hardware (2). If the caul plates (13) and (13) connected to the adjusting screws (12) and (12) are at appropriate positions, the hammer (1) is lifted in the state of FIG. ), The opening operation of the clamp (15) is performed smoothly and reliably.

However, if the adjusting screws (12) and (12) are excessively tightened when the clamp (15) is clamped by the clamp (15), the abutment plates (13) and (13) are moved inward. Since the lower end of the clamp (15) is too open because it protrudes too much, the contact state between the rotatable pins (5) (5) of the metal receiving object (2) and the support pins (10) (10) becomes unstable, and Hammer (1) when lifting (15)
May fall off the holding of the support pins (10) of the clamp (15) during the lifting. Also, use the adjustment screw (1
2) If the tightening of (12) is insufficient, the rotatable pins (5) and (5) of the receiving object (2) are too deeply mounted on the support pins (10) and (10) of the clamp (15). When lifting (1) and dropping it, the opening of the clamp (15) does not go smoothly, causing the hammer (1) to get caught on the clamp (15) or the hammer (1) to drop obliquely. May occur. Therefore, it is better to adjust the tightening of the adjusting screws (12) for each hammer used.

According to the chuck structure of the hammer and the clamp according to the present invention, there is an advantage that the hammer can be easily lifted again even if the hammer does not fall vertically on the ground surface and falls in an inclined state. That is, the clamp is inclined to the inclined receiving object of the hammer that has fallen in the inclined state, and the receiving object is chucked by the hydraulic cylinder. Next, the hammer may be pulled up while raising it in an oblique direction, and fine adjustment may be performed so that the hammer is finally vertical. As described above, according to the present invention, even when the hammer has to be lifted obliquely, it can be easily and quickly performed.

[0011]

As described above, according to the present invention, in the weight drop compaction method, the chuck for lifting the hammer can be made simple and reliable, and furthermore, the hammer can be dropped smoothly and horizontally reliably. Remarkable effects can be expected, such as improvement of ground quality and accurate ground improvement.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a hammer with a receiving member used in the present invention.

FIG. 2 is a side view showing one embodiment of a hammer with a receiving member used in the present invention.

FIG. 3 is a front view showing an embodiment of a clamp used in the present invention.

FIG. 4 is a main part front view showing an embodiment of the present invention and showing a chucked state between a receiving object and a clamp.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hammer 2 Hardware 3 Vertical steel plate 4 Oilless metal 5 Rotatable pin 6 Bolt 7 Hydraulic cylinder 8 Hanging shaft 9 Clamp arm 10 Support pin 11 Compression spring 12 Adjustment screw 13 Backing plate 14 Hanging wire rope 15 Clamp

Claims (1)

(57) [Claims] 1. A hammer drop chuck structure comprising a clamping clamp lifted by a crane or the like and capable of being opened and closed, and a hammer receiving member clamped by the clamp, comprising two rotatable pins fixed to the upper end of the hammer. It consists of a metal support that is pivotally supported in parallel with each other, and a clamp in which two parallel hammer support pins that abut against the lower end of the rotatable pin are fixed to the lower end. A chuck structure for dropping a hammer, characterized in that an abutment plate which is movable inward by contact is provided at a lower portion of the clamp so that an opening interval between the support pins can be adjusted.