JP2962406B2 - Pull rod grip device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pull rod grip device used in a device for press-fitting a building into the ground.

[0002]

2. Description of the Related Art When an underground structure (caisson or the like) is constructed on the ground and then excavated in the ground and buried in the ground, as shown in FIG. A pull rod 2 (a predetermined length is connected to a required length by screws) is connected to the anchor 1 for use, and a structure 3
The structure 3 is press-fitted downward by applying a pulling force with the hydraulic jack 4 and the pull rod grip device 5 installed at the top of the structure. Conventionally, as a pull rod grip device,
Japanese Utility Model Publication No. 61-27913 and Japanese Utility Model Application Laid-Open No. 6-5940.
No. 0 publication is known. Of these, Jiko 61-
As shown in FIGS. 6 and 7,
The grip piece 6 is supported by a rotating pin 7, and the load from the hydraulic jack is received by the rotating pin 7 and the grip base 8. 8 and 9, the load from the pull rod 2 is supported by the grip pieces 6 and the grip pieces 6 are spread between the grip pieces 6 to release the grip pieces 6, as shown in FIGS. The opening spring 9 is provided.

[0003]

[Problems to be solved by the invention]
No. 27913, a part of the press-fit load is applied to the rotating pin 7, so that the rotating pin 7 is supported by bearings at both ends in the longitudinal direction, and a press-fit load is applied to the central portion in the longitudinal direction. A bending moment is applied to the rotating pin 7, and as a result, the rotating pin 7 is frequently damaged. For this reason, actually, a device having no rotating pin is used as in Japanese Utility Model Laid-Open No. 6-59400,
In this type, an expansion spring 9 for releasing the grip pieces 6 must be incorporated between the grip pieces 6. However, due to severe use, the expansion spring 9 often breaks, and the replacement of the expansion spring 9 requires disassembling the entire grip device, reassembling after replacement, and complicating the operation. There is a problem that is. An object of the present invention is to provide a structure in which a rotating pin can be realized with a small diameter without applying a press-fit load to the rotating pin, and even if the expanding spring is broken, the entire device is disassembled for replacement. Another object of the present invention is to provide a pull rod grip device that does not require assembly.

[0004]

The present invention which achieves the above object of the present invention is as follows. (1) A plurality of grip pieces disposed around a grip device axis and rotatable around a horizontal rotation axis between a closed position and a release position, and the grip device axis as a center axis. A grip base, which receives the grip piece when the grip piece comes to the closed position, and transmits all of the force of the hydraulic jack to the grip piece, and is disposed radially outward of the grip base. When the grip piece is in the closed position and the grip base receives the grip piece, the grip piece can be rotated with a gap between the grip piece and the grip piece that does not receive any force from the grip piece. A rotary pin for loosely fitting and supporting, and a spring disposed radially outside of the grip base and constantly biasing the grip piece in a closing direction; Rurod grip device. (2) a casing in which the grip pieces and the grip base are housed, and a release arranged outside the casing and hung from the casing, and when pressed down, rotates all the grip pieces to the release side. The pull rod grip device according to claim 1, further comprising: a use ring.

In the device (1), the press-fit load from the grip piece is completely received by the grip base, and in this state, there is a gap between the grip piece and the rotary pin. No load is applied to
No bending moment is generated on the rotating pin. Therefore, the rotating pin may have a small diameter, and can be arranged around the grip base, resulting in a feasible structure. In the device of (2), the spring that always biases the grip piece in the closing direction is disposed radially outside the grip base, and it is not necessary to fix the spring between the grip pieces. Only the spring can be easily replaced without disassembling the base and the grip piece.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A pull rod grip device according to an embodiment of the present invention will be described with reference to FIGS. FIG.
Similarly, a reaction force anchor 1 buried and fixed in the ground
Is connected to a pull rod 2 (a required length is connected to a predetermined length by a screw). As shown in FIGS. 3 and 4, the upper pull rod grip device 10 is installed via a hydraulic jack 12 on a support member 11 installed on the structure 3 to be pressed. In the support member 11, a lower pull rod grip device 10 (having the same structure as the upper pull rod grip device 10) is installed. The pull rod 2 is a support member 1
1. The hydraulic jack 12 and the upper and lower pull rod grip devices 10 are inserted.

As shown in FIGS. 1 and 2, a pull rod grip device 10 includes a grip piece 13 and a grip base 1.
4, a rotating pin 15, a spring 16, and a casing 17
And a release ring 18. Grip piece 13
Are provided around the axis of the grip device, and are rotatable between the closed position and the release position around the horizontal rotation axis of each grip piece 13. The grip base 14 has a conical concave surface 19 whose center axis is the axis of the grip device.
When the grip 3 is in the closed position, the grip 13 is received, and in this state, all the force of the hydraulic jack 12 is transmitted to the grip 13.

The rotating pin 15 is disposed radially outward of the grip base 14, and the grip piece 14 is in the closed position, and the grip base 14 receives the grip piece 13. The grip piece 13 is loosely fitted and supported rotatably with a gap 20 (at least a gap provided in the vertical direction) that does not receive any force from the grip. The grip piece 13 has an arm 13a (a part of the grip piece), and the arm 13a extends radially outward. The spring 16 is disposed radially outward of the grip base 14, extends between the casing 17 and the arm 13a, and constantly biases the grip piece 13 in the closing direction.

The casing 17 houses the grip piece 13 and the grip base 14 inside. Casing 1
7 has a bottom wall, a ceiling wall, and a side wall, and a hole for inserting the pull rod 2 is provided in the bottom wall and the ceiling wall. The release ring 18 is suspended from a side wall of the casing 17 via a suspension spring. The arm 13 a of the grip piece 13 is provided with a slit 22 provided on a side wall of the casing 17.
And extends out of the casing 17. When the release ring 18 is pressed down by hand, the grip piece 13 is released.
Arm 13a of the grip piece 13
a is depressed, and the grip piece 13 is rotated toward the release position to the release position.

Next, the operation will be described with reference to FIGS.
explain. First, as shown in FIG.
Is operated upward (jack extension direction). At this time, the upper pull rod grip device 10 moves upward while the grip piece 13 is in the closed position and the pull rod 2 is gripped, and the lower pull rod grip device 10 moves the pull rod 2 to the lower position when the grip piece 13 is in the release position. The pull rod grip device 10 is freely moved upward. Pull rod 2 is anchor 1 buried underground (Fig. 5)
, The reaction force is applied to the press-fitted structure 3, and the press-fitted structure 3 is pressed into the ground.

Next, as shown in FIG. 4, the hydraulic jack 12 is operated in a downward direction (jack contracting direction). At this time, the upper pull rod grip device 10 moves the pull rod 2 freely upward with respect to the upper pull rod grip device 10 with the grip piece 13 in the release position, and the lower pull rod grip device 10 moves the grip piece 13 to the closed position. And the pull rod 2 is gripped. By repeatedly expanding and contracting the hydraulic jack 12, the hydraulic jack 12 and the upper and lower pull rod grip devices 10
It moves downward like a sniffer bug with respect to the pull rod 2, and presses the press-fitted structure 3 into the ground.

Next, the operation of the pull rod grip device 10 will be described with reference to FIGS. In the apparatus according to the embodiment of the present invention, the press-fit load (also the load of the hydraulic jack 12) from the grip piece 13 is completely received by the grip base 14, and in that state, the rotary pin insertion hole of the arm 13a of the grip piece 13 and the rotary pin 15 so that there is a gap 20 between the grip piece 13 and the rotating pin 1.
5 is not applied, and no bending moment is generated on the rotating pin 15. Therefore, the rotating pin 15 is
It is only necessary to be able to rotatably support, so that it may be of small diameter and not large, so that it can be arranged in space around the grip base 14, resulting in a feasible structure. Further, the spring 16 for constantly biasing the grip piece 13 in the closing direction is provided on the grip base 14.
And it is not necessary to stick between the grip pieces as in the prior art. Therefore, even if the spring 16 breaks, the spring 16 is easily disassembled without disassembling the grip base 14 or the grip piece 13. Can be replaced with Further, when the press-fitting device is removed after the press-fitting is completed, it is necessary to release the grip piece 13. However, by pressing down the release ring 18 against the suspension spring 21, the arm is released by the release ring 18. 13a down,
The grip can be easily released by rotating the grip piece 13 to the release side.

[0013]

According to the first aspect of the present invention, all the press-fitting load from the grip piece is received by the grip base, and in this state, there is a gap between the grip piece and the rotating pin. No load is applied to the rotating pin, and no bending moment is applied to the rotating pin. Therefore, the rotating pin may have a small diameter, and can have a feasible structure. In addition, the spring that always biases the grip piece in the closing direction is located outside the grip base in the radial direction and there is no need to stick it between the grip pieces, so even if the spring breaks, the grip base and the grip piece Only the spring can be easily replaced without disassembly. According to the second aspect of the present invention, since the release ring is provided, it is possible to easily release the pull rod grip device by depressing the release ring.

[Brief description of the drawings]

FIG. 1 is a plan view of a pull rod grip device according to an embodiment of the present invention.

FIG. 2 is a sectional view of the apparatus of FIG.

FIG. 3 shows a state in which a pull rod grip device according to an embodiment of the present invention is attached to a pull rod and a structure is press-fitted.
It is a front view when a hydraulic jack is in an extended state.

FIG. 4 shows a state in which a pull rod grip device according to one embodiment of the present invention is attached to a pull rod and a structure is press-fitted.
It is a front view when a hydraulic jack is in a contracted state.

FIG. 5 is a perspective view of a state in which a conventional pull rod grip device is attached to a pull rod and a structure is being press-fitted.

FIG. 6 is a sectional view of a pull rod grip device disclosed in Japanese Utility Model Publication No. 61-27913.

FIG. 7 is a plan view of a pull rod grip device disclosed in Japanese Utility Model Publication No. 61-27913.

FIG. 8 is a sectional view of a pull rod grip device disclosed in Japanese Utility Model Laid-Open No. 6-59400.

FIG. 9 is a plan view of a pull rod grip device disclosed in Japanese Utility Model Laid-Open No. 6-59400.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Anchor for reaction force 2 Pull rod 3 Structure to be press-fitted 10 Pull rod grip device 11 Support member 12 Hydraulic jack 13 Grip piece 13a Arm 14 Grip base 15 Rotating pin 16 Spring 17 Casing 18 Release ring 19 Conical concave surface 20 Gap 21 Hanging Spring 22 slit

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Kamiya 1-13-6 Nagashiro, Koto-ku, Tokyo Inside Topy Construction Co., Ltd. (56) References JP-A 7-2911591 (JP, A) JP-A Sho 48-68970 (JP, A) JP-A-8-218371 (JP, A) JP-B-51-45858 (JP, B2) JP-B-51-1905 (JP, B1) US Patent 5380056 (US, A) ( 58) Field surveyed (Int.Cl. ⁶ , DB name) B66F 1/08 B66F 3/24-3/25 B66F 19/00

Claims (2)

(57) [Claims] 1. A plurality of grip pieces arranged around a grip device axis and rotatable between a closed position and a released position around respective horizontal rotation axes, and a center of the grip device axis. A grip base having a conical concave surface serving as an axis, receiving the grip piece when the grip piece comes to the closed position, and transmitting all of the force of the hydraulic jack to the grip piece; and a radially outer side of the grip base. The grip piece is rotated with a gap between the grip piece and the grip piece in a state where the grip piece is in the closed position and the grip piece receives the grip piece with no gap from the grip piece. A rotatable pin that loosely fits and supports, and a spring that is disposed radially outside of the grip base and constantly biases the grip piece in a closing direction. Pull rod grip device. 2. A casing in which the grip piece and the grip base are accommodated, and a casing arranged outside the casing, hung from the casing, and rotates all the grip pieces to the release side when pushed down. The pull rod grip device according to claim 1, further comprising: a release ring for causing the pull rod to be released.