JPH0716892B2 - Deformed bar rotation chuck - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chuck used when a deformed bar is fixed to a structure made of a plastic body such as concrete by a chemical fixing force.

[0002]

2. Description of the Related Art For example, when a seismic wall is installed in a concrete structure, deformed reinforcing bars are embedded and fixed in the existing structure and the reinforcing bar of the seismic wall is connected to integrate the existing structure and the seismic wall to be post-cast. The construction method is widely used. In order to embed and fix deformed reinforcing bars in an existing structure, generally, a method using chemical bonding force is used.

That is, an embedding hole is bored in an existing structure with a drill, and a capsule containing a synthetic resin-based main agent and its curing agent separately stored is loaded into the embedding hole and the deformed rebar is rotated. It is inserted into the embedding hole, the capsule is crushed, the main agent and the hardening agent are sufficiently stirred and mixed, rotation is stopped, and the deformed bar is left in the embedding hole and fixed as it is until the mixture hardens. is there.

However, as is well known, the deformed reinforcing bar has a rib extending in the longitudinal direction and a bush extending in the circumferential direction on the outer peripheral surface, and a normal chuck is firmly bite to rotate the rotary power tool. Since it is extremely difficult to properly transmit the above, a chuck for deformed rebar has been developed, one of which is disclosed in Japanese Utility Model Laid-Open No. 60-17964.

In the deformed rebar rotation chuck disclosed in this publication, a lock pin is inscribed in a long hole having a substantially triangular end face provided in the main body so as to be opened to the front end face, and a circular inner cylinder having an end face is provided. It is loosely fitted, and the lock pin is fitted in the groove hole formed in the inner cylinder, and a part of the lock hole is projected and retracted into the inner cylinder depending on the contact position of the elongated hole with the inner peripheral wall.
When the deformed rebar is inserted into the inner cylinder and the main body is rotated, when the lock pin comes into contact with the part of the triangular inner wall of the long hole that is close to the central axis of the main body, part of it will come out of the slot into the inner cylinder. When the lock pin projecting inside the inner cylinder engages with the rib, the deformed bar further rotates integrally with the main body and the inner cylinder. Three lock pins are provided at equal intervals in the circumferential direction.

That is, the chuck has a construction in which three lock pins and an inner cylinder are built in a long hole of the main body, and in addition to having a large number of parts, it can be used only for deformed reinforcing bars having a diameter suitable for the inner cylinder. Therefore, it is necessary to prepare a dedicated chuck for each deformed rebar having a different diameter, which is an economical burden and a management trouble. Further, since the lock pin makes a line contact with the inner peripheral wall of the long hole and transmits the rotational force to the inner cylinder and the deformed reinforcing bar, one or both of the lock pin and the long hole is easily worn, and rattling occurs in a relatively short period. There is a problem that it occurs or becomes unusable.

[0007]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is that the rotating force can be properly transmitted to the deformed rebar with a simple structure, and that the ones having different diameters can be surely rotated. The point is that there was no excellent deformed rebar rotation chuck.

[0008]

In order to solve the above-mentioned problems, according to the present invention, a plurality of eccentric arc surfaces which are gradually distant from the center toward the same circumferential direction are formed side by side in the circumferential direction. A main body having an insertion hole which is connected to the rotary power tool; an outer peripheral surface having the same diameter as the eccentric circular arc surface, and an inner peripheral surface having unevenness for engaging the rib of the deformed rebar, And a plurality of gripping pieces that gradually become thicker from one end to the other end, and the gripping piece has a thick side end located farther from the center of the eccentric arc surface and is inserted into the insertion hole. It has a structure in which it is separately movably mounted in the circumferential direction and in the radial direction; and with such a structure, it is adaptable to deformed rebars having different diameters with a simple structure, and durability to appropriately transmit rotational force. Achieving the purpose of providing a chuck for rotating deformed rebar with excellent .

[0009]

[Function] When the deformed bar is inserted into the insertion hole and the main body is rotated, the gripping pieces arranged around the deformed bar are moved toward the center by the eccentric arc surface, and the irregularities engage the ribs of the deformed bar. Like When the main body is further rotated, the gripping pieces are further moved toward the center to firmly engage with the ribs and become immovable in the central direction, and thereafter, the main body, the gripping pieces, and the deformed reinforcing bars are integrally rotated. Deformed bars can be bitten even if they have different diameters as long as they are smaller than the inscribed circle of their inner peripheral surfaces when the grip pieces are farthest from the center.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The main body 1 has a square hole, which is a connecting portion 3 into which the distal end portion of the drive shaft of the rotary power tool is fitted, and which is open at the base end surface. A socket 2 having a screw shaft 4 and a stopper 5 protruding from the tip thereof, and a housing 6 having a screw hole 7 at the base end and an insertion hole 8 opened to the tip surface.
The screw shaft 4 is screwed into the screw hole 7 and the stopper 5 is projected to the bottom of the insertion hole 8 to connect the socket 2 and the housing 6.

The insertion hole 8 is formed with two eccentric circular arc surfaces 9 having a substantially one-half circumference length, which are gradually distant from the center toward the same circumferential direction, and are arranged in the circumferential direction. The two eccentric circular arc surfaces 9, 9 are centrally symmetrical and are formed from the vicinity of the inlet of the insertion hole 8 to the bottom.

Next, the gripping piece 1 inserted in the insertion hole 8
1 comprises an outer peripheral surface 12 of an arc surface having the same diameter as the eccentric arc surface 9 and an inner peripheral surface 14 of an arc shape having a concave portion 13 composed of a plurality of grooves extending in the axial direction, and from one end It is formed in an arc wedge shape that is slightly shorter than the half circumference length that gradually becomes thicker toward the other side end, and has an axial length substantially equal to the eccentric arc surface 9. .

Two of these gripping pieces 11 are inserted into the insertion holes 8 with their thick side edges being located farther from the centers of the two eccentric arc surfaces 9 and along them. The spring piece 1 has a notched annular shape that is movable in the circumferential direction and the radial direction, and is fitted to the inlet end of the insertion hole 8.
It is held inside the insertion hole 8 by an annular seat plate 17 fixed by 6 so as not to be pulled out.

In this embodiment thus constructed, the main body 1 is connected to the rotary power tool by the connecting portion 3, and the deformed bar is inserted into the insertion hole 8 and held to rotate in the embedding hole of the concrete structure. , Crushing a capsule containing a main agent of a synthetic resin adhesive and a curing agent and thoroughly stirring and mixing them,
The deformed bar is left in the embedding hole and fixed.

First, when inserting the deformed bar 21 into the portion of the insertion hole 8 surrounded by the inner peripheral surface 14 of the gripping piece 11, the gripping piece 11 is farthest from the center, that is, an eccentric arc. The deformed bar 21 having a diameter smaller than the inscribed circle of the inner peripheral surface 14 when the thick side edge is located at the portion farthest from the center of the surface 9 can be inserted, and the gripping piece 11 can be inserted around the circumference. It can move a little in the direction and in the radial direction (see FIG. 4A).

When the deformed rebar 21 is inserted in this way,
When the main body 1 is rotated counterclockwise in FIGS. 2 and 4, a portion near the center of the eccentric arc surface 9 moves toward the thick side edge, so that the gripper piece 11 has an outer peripheral surface 12 having an eccentric arc surface. It comes in contact with 9 and comes closer to the center.
The rib 22 extending in the longitudinal direction of 1 fits into the recess 13 (see B in FIG. 4).

When the main body 1 is further rotated, the gripping piece 11
Is gradually rotated, but if necessary, the deformed reinforcing bar 21 is fixed so that the deformed reinforcing bar 21 is further moved toward the center and the rib 22 is deeply fitted into the recess 13. When the gripping piece 11 becomes immovable in the center direction by the deformed rebar 21 in this way, the eccentric arc surface 9 comes into surface contact with the outer peripheral surface 12 in a close contact state, and thereafter, the main body 1, the gripping piece 11, and the deformed shape. The rebar 21 will rotate integrally (see C in FIG. 4).

When the main body 1 is slightly rotated in the opposite direction when the rotation is stopped, the gripping piece 11 is loosened.
When moving in the base end direction as it is, the deformed rebar 21 is pulled out from the portion surrounded by the gripping piece 11, and thus can be left in the embedding hole of the concrete structure.

In this embodiment, the number of the eccentric arc surfaces 9 is two, but the number of the eccentric arc surfaces 9 may be three or more, and the gripping pieces 11 may be arranged inside each.

[0020]

According to the present invention, the main body having the insertion hole for the deformed rebar and the plurality of eccentric arc surfaces formed on the peripheral surface of the insertion hole allow the inner peripheral surface surrounding the deformed rebar to move. Since it consists of a gripping piece, the number of parts is small and the configuration is simple, as well as deformed rebars with different diameters can be reliably bited and the rotating force can be transmitted appropriately, so prepare a dedicated chuck for each It is not necessary and has great economic and management advantages. Further, since the main body and the grip portion are in surface contact with each other to transmit the rotational force to the deformed rebar, there is little wear and the durability is excellent.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is an exploded end view of the main body and the grip piece.

FIG. 4 is an explanatory diagram of a situation where a deformed reinforcing bar is bitten.

[Explanation of symbols]

1 main body, 3 connecting parts, 8 insertion holes, 9 eccentric arc surface,
11 gripping piece, 12 outer peripheral surface, 13 unevenness, 14
Inner circumference,

Claims (1)

[Claims] 1. A peripheral surface has insertion holes formed with a plurality of eccentric circular arc surfaces which are gradually distant from the center in the same circumferential direction and are arranged side by side in the circumferential direction, and are connected to a rotary power tool. A main body; an outer peripheral surface having the same diameter as the eccentric circular arc surface, and an inner peripheral surface having unevenness for engaging a rib of the deformed rebar,
A plurality of gripping pieces that gradually become thicker from one side end to the other side end, and the gripping piece has its thicker side end located farther from the center of the eccentric arc surface. And a chuck for rotating a deformed rebar, which is movably inserted into the insertion hole separately in the circumferential direction and the radial direction.