JPH021568B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a sleeve for a large-diameter reinforcing bar joint.

(Prior art) Sleeves for large-diameter reinforcing bars are designed to increase frictional force to counter the tensile force acting on large-diameter reinforcing bars.
It is necessary to form unevenness such as a waveform on the inner peripheral surface.

For this reason, conventional sleeves are either integrally formed by casting as shown in Japanese Utility Model Publication No. 52-30166, or the inner peripheral surface of a normal sleeve is machined to form irregularities.

(Problems to be Solved by the Invention) However, if the sleeve is formed by casting, it will be large and thick, and if the inside of the sleeve is machined, the process will be complicated and costs will increase. .

This invention was devised to solve the above problems, and its purpose is to provide a method for manufacturing a sleeve for reinforcing bar joints, which allows the sleeve to be made more compact, facilitates work, and reduces costs. shall be.

(Means for Solving the Problems) This invention involves attaching a plurality of rings to the outer peripheral surface of a cylindrical core, fitting them into a sleeve, and crimping them onto the outer periphery of the sleeve while rotating a plurality of rolls. After applying compressive force, the core is removed from the sleeve, and a plurality of rings are driven into the sleeve to form irregularities.

A plurality of annular grooves are formed on the outer periphery of the core, and a truncated conical cavity continuous in the longitudinal direction is formed in the core. The structure of the core is divided into a plurality of separate parts in the circumferential direction, and the end face of each component is fan-shaped.

The ring is formed so that its outer periphery protrudes like an edge.

To attach the ring to the core, after fitting the ring into the annular groove of the core, drive a wedge into the cavity of the core to enlarge the diameter of the core, which will prevent play between the annular groove and the ring. Make sure there is no such thing.

(Example) The present invention will be described below based on an example shown in the drawings.

As shown in Figures 1 and 4, the cylindrical core 1
A plurality of rings 4 are attached to the outer peripheral surface of the sleeve 6 and inserted into the sleeve 6.

The ring 4 is made of steel and has an edge-shaped outer circumference as shown in FIG.
It is designed to easily bite into the inner peripheral surface of the sleeve 6.

The structure of the core 1 is a separate shape divided into four parts in the circumferential direction, and the end surface of each component part 1a is fan-shaped. After driving the ring 4 into the inner peripheral surface of the sleeve 6, the core 1 is inserted through the sleeve 6. It can be easily taken out.

A plurality of annular grooves 2 for supporting rings 4 are formed on the outer periphery of the core 1, and a truncated conical cavity 3 connected in the longitudinal direction is formed in the core of the core 1.
is formed.

After fitting the ring 4 into the annular groove 2 of the core 1, a wedge 5 is driven into the cavity 3 to enlarge the diameter of the core 1 and prevent play between the annular groove 2 and the ring 4. .

The core 1 with the wedge 5 and the plurality of rings 4 attached is inserted into the sleeve 6 using the above procedure. In order to facilitate insertion, the outer diameter of the ring 4 and the inner diameter of the sleeve 6 are fitted with a slight clearance. Further, the core 1 is inserted into the sleeve 6 from the side where the diameter of the cavity 3 is smaller.

In the embodiment shown in FIG. 1, a filler pipe 8 is attached to the lower part of the sleeve 6 via diamond sand 7. This furler pipe 9 is made of reinforcing steel 9 in advance.
It is fitted on the top edge of the .

In the embodiment shown in FIG. 4, a plurality of cores 1 each having a wedge 5 and a plurality of rings 4 attached thereto are successively inserted into a sleeve 6 as described above.
As shown in the figure, the wedges 5 and 5 adjacent to each other are brought into contact with each other at their ends, and when the lower end of the lowest wedge 5 is struck, the upper wedge 5 also comes out of the core 1 successively. . Therefore, a certain clearance is provided between the upper end surface of the wedge 5 and the lower end surface of the core 1 directly above the wedge 5.

A plurality of rolls 10 and 13 are arranged around the outer circumference of the sleeve 6.
A plurality of rings 4 are driven into the sleeve 6 by crimping while rotating and applying compressive force.

Before the compression process, compression force is applied to the upper end of the sleeve 6 using a die 11 (see FIGS. 1 and 4).

As an example of the compression process, as shown in FIGS. 5 and 6, three rolls 1 are placed around the sleeve 6.
There is a method of compressing the sleeve 1 and pulling the sleeve 6 upward. In FIG. 6, the axis of the roll 10 is arranged at an angle of about 45° to 60° with respect to the longitudinal direction within the sleeve 6, but it may be arranged at an angle of 90°.

As another example of the compression process, as shown in FIGS. 7 and 8, three rolls 13 having a spiral convex portion 12 formed on the outer periphery are used so that the axes of the rolls 13 are parallel to the longitudinal direction of the sleeve 6. There is a method of compressing the sleeve 6 by arranging the rolls 13 as shown in FIG.

Finally, the core 1 is removed from the sleeve 6.

In the embodiment shown in FIG. 1, the wedge 5 is pulled out from above (larger diameter), and in the embodiment shown in FIG. 4, the lower part (smaller diameter) of the wedge is struck with a hammer or the like. Then, play occurs between the wedge 5 and the cavity 3 of the core 1, so that the core 1 can be easily removed from the sleeve 6.

Since the ring 4 is driven into the sleeve 6, when the core 1 is removed, unevenness will be formed in the sleeve 6 as shown in FIG.

Example of use of sleeve When using the sleeve 6 manufactured by the above procedure, insert the upper end of the lower column reinforcing bar 14 and the lower end of the upper column reinforcing bar 15 into the sleeve 6 as shown in FIG. Filler 16 is injected between 15 and sleeve 6.

(Effect of the invention) Since the unevenness is formed by attaching a plurality of rings inside the sleeve, it can be formed by casting,
The cost is lower than that of a sleeve in which cutting is performed on the inside, and the sleeve can be made more compact.

The process involves inserting a core with multiple rings attached into the sleeve, compressing the sleeve by rotating and crimping multiple rolls around the outer circumference of the sleeve, and then removing the core, so it is not a conventional cutting process. The work is easier than those that require

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the present invention;
The figure is a front view of the ring, FIG. 3 is an enlarged cross-sectional view taken along the - line in FIG. 1, FIG. 4 is a sectional view showing another embodiment of the present invention, and FIG. 6 is a side view of FIG. 5, FIG. 7 is a plan view showing another example of the compression process, FIG. 8 is a side view of FIG. 7, and FIG. 9 is an example of the sleeve manufactured according to the present invention. FIG. 10 is a sectional view showing an example of the use of the sleeve manufactured according to the present invention. DESCRIPTION OF SYMBOLS 1... Core, 1a... Component, 2... Annular groove, 3... Cavity, 4... Ring, 5... Wedge, 6... Sleeve, 7... Diamond sand, 8... Filler pipe, 9...Reinforcing bar, 10...Roll, 11
...Dice, 12...Protrusion, 13...Roll, 1
4...Lower column reinforcing bars, 15...Upper column reinforcing bars, 16...
...Filling material.

Claims (1)

[Claims] 1 A plurality of annular grooves are formed on the outer periphery, a truncated conical cavity continuous in the longitudinal direction is formed in the core, and the outer periphery is in the annular groove of the core which is divided into a plurality of parts in the circumferential direction. After attaching a plurality of rings formed to protrude in an edge shape and fitting a wedge into the cavity of the core, the core with the rings and wedges attached integrally is inserted into the sleeve, and the outer circumference of the sleeve is Manufacture of a sleeve for reinforcing bar joints, characterized in that after crimping and applying compressive force while rotating a plurality of rolls, the wedge and core are removed, and a plurality of rings are driven into the sleeve to form unevenness. Method.