JPS6239867Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to a device for straightening the bending of a coiled steel wire so as not to cause a reduction in relaxation or yield load. Heat stretch steel wire (HS wire) is a PC steel wire with extremely low stress relaxation loss in order to stably apply prestress to autoclaved concrete. In order to achieve low relaxation, this steel wire is manufactured by simultaneously applying heating in the bluing temperature range and tensile load to the steel wire. This is called heat stretch treatment, or HS treatment for short. After HS treatment, it cannot be transported for a long time, so it is rolled up and transported. If the HS wire sent to the concrete factory is immediately stretched into a straight line, it will not become curly, but if it is stored as a coil, it will gradually become curly and will not become straight when stretched. This results in a curved state. When burying HS wires in concrete,
If there is residual bend in the HS wire, it will be difficult to draw it out from the coil, cut it to the required length, and arrange it in the formwork. In order to remove residual bends, the bends can be straightened by straightening using a conventionally used rotary straightening machine. Stress relaxation loss increases and the characteristics of the HS line are lost. The present invention aims to provide a device capable of correcting residual bending of an HS wire without reducing yield load or increasing stress relaxation loss. To achieve this goal, we investigated the bending of the HS winding material and found that when the HS wire is pulled out from the coil, it has a residual strain that causes it to rotate 360 degrees (one rotation) at a length of 20 to 25 m. It was found that the direction of rotation was counterclockwise as viewed from the direction in which the coil was pulled out, and that as the coil was pulled out as it rotated, the direction of bending also rotated, resulting in a bend of 25 to 35 mm/2 m. It was also found that this rotational and bending strain increases with storage time, and the above-mentioned strain occurs after about 3 weeks. The cause of this phenomenon has not yet been elucidated. From this, it has been found that the further the position of the straightening device is from the coil pull-out position, the more the HS wire rotates, the more variation in the amount of rotation, and the more difficult it is to straighten the wire by pushing it in the opposite direction to the bending direction. Based on this knowledge, the present invention is designed to move the straightening rolls so that the straightening position can be brought as close as possible to the wire drawing position, and the straightening direction can be made to match the bending direction of the wire as much as possible. The supporting roll table is provided in a tiltable manner. Based on this idea, the present invention has a structure on the top of the swift on which the coiled wire is placed, which is movable in the tangential direction of the winding circle of the wire placed on the swift, and is perpendicular to the rotation center axis of the swift. A roll table having a flat upper surface tiltable toward the outside of the Swift from a plane perpendicular to the rotation center axis of the Swift about an intersection line between the surface and a vertical plane including the tangent line; , two rolls spaced apart along the tangent line and rotatably provided on the swift side around a central axis perpendicular to the top surface of the roll table, and a roll located outside the swift than the two rolls in the middle of the two rolls. and one roll located in the opposite direction and rotatable around a central axis perpendicular to the upper surface of the roll table, and provided between the two rolls so that the facing position can be adjusted. This device constitutes a winding material bend straightening device. An embodiment of the present device shown in the figure will be described. A Swift 6 is placed on the ground so as to rotate around its center on a horizontal plane. A wire rod 5 wound into a coil is placed in the annular cage of the swift 6. A rail extending in the tangential direction of the outer periphery of the Swift 6 is provided on the ground on the side surface of the Swift 6, and a moving platform 4 is provided on the rail so as to be movable along the rail. The upper end of the moving platform 4 is higher than the upper end of the outer circumference of the annular car of the Swift 6, and a support arm 3 extends from this upper end to the upper part of the annular car of the Swift 6 in parallel with the rail.
are integrated. One end 3a of the support arm 3 on the swift 6 side is bent at 90 degrees and bent upward. The roll table 2 is plate-shaped and one end 2a is bent at 90 degrees.
One end 2a is attached to the outer surface of one end 3a of the support arm 3 with a bolt 9 so that the bent corner is located upward. A pair of pull-out rolls 7 driven by a motor are arranged on an extension of the rails away from the swift 6 at the same height as the flat upper surface of the roll table 2. On the upper surface of the roll stand 2, there is a space between the inside of the outer periphery of the annular basket of the Swift 6 and a pair of opposing surfaces of the pull-out roll 7 when viewed from above so as to pull out the coiled wire 5 placed in the Swift 6 from the outermost periphery. Two rolls 1a and 1b are provided rotatably around a center line perpendicular to the top surface of the roll table 2 along a line connecting the two rolls 1a and 1b at intervals on the swift 6 side of this line,
A roll 1c is provided between the rolls 1a and 1b so as to be rotatable around a center line perpendicular to the upper surface of the roll table 2, and located further outside the swift 6 than the rolls 1a and 1b. The central axis of roll 1c is roll 1a,
It is provided so that its position can be adjusted in a direction perpendicular to a line connecting the centers of 1b. As mentioned above, in this embodiment, the wire rod 5 placed in the annular cage of the swift 6 is pulled out from the outermost periphery of the winding ring of the wire rod 5. This is to avoid bending the wire 5 as much as possible, since if the part of the wire 5 that is at the diameter of the ring is pulled out at a position where the diameter is small, the wire will be bent inward by that amount. However, there is no problem even if the wire 5 is pulled out from a position slightly inside the maximum outer diameter of the ring. Support arm 3
The bolt 9 insertion hole at one end 3a of the rolls 1a, 1
By moving the position of the bolt 9 in the long hole 8 and tightening the bolt 9, the roll base 2 can be moved to the rolls 1a, 1b. It is provided so that it can be fixed at an angle with respect to a plane perpendicular to the center line of the swift 6, with the wire rod 5 in contact with the wire rod 5 as the center. To straighten the wire rod 5 using this device, move the moving table 4 along the rail, move the roll table 2 to the outside of the Swift 6, and hang the coiled wire rod 5 with a crane. Place it in the ring-shaped basket No. 6. Then, the swift 6 is rotated and the wire 5 is pulled out straight from one end in a free state and viewed. As the drawer length increases, the bending direction of the wire rod 5 as seen from the drawer side gradually rotates counterclockwise, and the bending becomes larger. For example, measure the length when the bending direction is rotated 360 degrees, and divide 360 degrees by the length (m) to find the rotation angle per 1 meter. Also, by dividing the bending depth by the length at that time, the bending depth per meter can be obtained. Next, the drawn wire 5 is wound up in the annular basket of the swift 6, and the moving table 4 is moved toward the swift 6 so that the roll table 2 is positioned above the annular basket of the swift 6. And roll 1c
The wire rod 5 is located at a position indicated by K in FIG. 1, that is, at a distance of, for example, 1 m from the diameter perpendicular to the drawing direction of the wire rod 5. Next, loosen the bolt 9 and turn the roll stand 2 counterclockwise when viewed from the direction in which the wire rod 5 is pulled out, so that it is tilted with respect to the horizontal by the rotation angle per 1 m, as shown by H in FIG. 5 of the roll 1c. The indentation amount is set to 1 roll for the bending depth per 1 m.
The wire is pushed and bent in the opposite direction to the bending direction by an amount corresponding to the bending depth between a and 1b.
Then, the wire is passed between the rolls 1a, 1b, and 1c, and the wire 5 is continuously pulled out from the swift 6 by a pull-out roll 7, and the bend in the wire is straightened. The twist of the wire 5 is not related to straightening. The characteristics of a 9mm diameter HS wire (JIS G 3536PC steel wire) wound into a coil with an inner diameter of 2.1m and an outer diameter of 2.4m after straightening the bend using the above device were measured using a conventional rotary straightening machine. The following is a comparison of cases in which correction was performed using the method and one case in each case. The rolls 1a, 1b, and 1c are 90 mm in diameter and have a semicircular guide groove on the outer periphery with a width of 10 mm and a depth of 5 mm.The distance between the centers of the rolls 1a and 1b is 240 mm, and the roll 1c is placed exactly in the middle. 5th
The indentation amount shown by H in the figure was 4.2 mm, and the inclination angle shown in FIG. 3 was 5 degrees. Then, the roll 1c was drawn out at a linear speed of 35 m/min and straightened with a distance K from the drawing position of the wire 5 to the center of the roll 1c of 1 m. The bend of the wire 5 drawn out in its free state is
The rotation in the 35mm/2m bending direction was 36m and 180°.

[Table] The main parts of the conventional straight line machine used in the above test are
As shown in the figure, there are 5 pieces in one row of pieces 11 cut in half on the diameter with a pitch of 150 mm, and 5 pieces of wire rod 5.
In a cylinder 10 with an inlet and an outlet, there are five
The cylinder is eccentrically set by mm and fixed with a bolt 12, and the cylinder is rotated at 2000 revolutions per minute while the wire 5 is passed through the cylinder at a speed of about 40 m per minute for correction. In this way, according to the proposed device, the wire is accurately bent in the direction opposite to the bending direction to straighten the wire, and no bending other than the minimum necessary bending is applied to the wire, so the characteristics of the wire can be improved. It can be corrected without damaging it.

[Brief explanation of the drawing]

Fig. 1 is a plan view of one embodiment of the present device, Fig. 2 is a front view of Fig. 1, Fig. 3 is a side view of the portion taken along line E-A in Fig. 1, and Fig. 4 is a plan view of the part shown in Fig. 5 is a plan view of FIG. 4, and FIG. 6 is a sectional view of a main part of a conventional straight line machine. 1a, 1b, 1c...Roll, 2...Roll stand, 2a...One end, 3...Support arm, 3a...One end, 4...Moving table, 5...Wire rod, 6...Swift, 7... Drawer roll, 8...long hole, 9...bolt.

Claims (1)

[Scope of utility model registration request] On the upper part of the Swift on which the wire wound into a coil is placed, there is provided a vertical plane that is movable in the tangential direction of the winding circle of the wire placed on the Swift, and that includes a plane perpendicular to the central axis of rotation of the Swift and the tangential line. a roll table having a flat top surface tiltable toward the outside of the swift from a plane perpendicular to the central axis of rotation of the swift about the intersection with the plane; Two rolls are provided on the Swift side to be rotatable around a central axis perpendicular to the top surface of the roll table, and a roll is provided on the top surface of the roll table located outside of the Swift from the two rolls in the middle of the two rolls. 1 provided so as to be rotatable around a central axis perpendicular to , and to be able to adjust its facing position between the two rolls.
A device for straightening the bending of a wire winding material, characterized in that the device comprises: