JPS5911121Y2 - Manufacturing equipment for precast concrete parts - Google Patents

Description

[Detailed description of the invention] The present applicant differs in U.S. Pat. No. 53-126931,
In an apparatus for manufacturing a precast concrete member in which a steel plate 1 is anchored on the surface of a concrete part, the bolt hole 2 is covered with the back surface of the steel plate 1 and is arranged concentrically with the bolt hole 2. A transparent resin cap 5, which is formed by fitting a nut 3 and a washer 4 slidably and loosely in the radial direction of the bolt hole 2, is disposed in the bolt hole 2, and is inserted into and detachably from the bolt hole 2. The screw rod 8, which is screwed into the tip end surface of the temporary bolt 6 and crimped by the screw 7 inserted from the side, is inserted into the head through hole 9 of the cap 5, and the cap head of the screw rod 8 is inserted. We have proposed an apparatus for manufacturing a precast concrete member in which the outer circumferential edge of the cap 5 is crimped to the steel plate 1 by screwing and tightening a nut 10 onto the protruding part.

(See Figure 1) When manufacturing a precast concrete member using the same device, concrete 11 is poured on the back of the steel plate 1, and after the poured concrete 11 has hardened, the temporary bolt 6 is screwed onto the tip of the concrete 11. The screw rod 8 of the part is detached from the nut 5 and removed to the outside of the steel plate 1, and the cap 5,
The washers 3 and nuts 4 and 10 are left in the concrete part, and when the steel plate 1 of the precast concrete member produced in this way is friction-welded to the steel plate 12 of another member, the steel plate 12 collides with the steel plate 1. , a high-tension bolt 14 for permanent installation is inserted into the bolt hole of the steel plates 1 and 12 so that the washer 13 is interposed between the steel plate 12 and the bolt head, and then inserted through the washer 3 and screwed into the nut 4. At this time, the nut 4 moves in the radial direction of the bolt hole 2, and the high tension bolt 14 for permanent installation and the inclined surfaces 14a, 4a provided on the opposing surface of the nut 4 collide with each other. The nut 4 is forcibly moved coaxially with the central axis of the high tension bolt 14 for permanent installation and is screwed into place.

In the above device, by using the cap 5 made of transparent resin, the presence or absence of a nut in the cap 5 can be confirmed from the outside during the production of a precast concrete member, and it is possible to prevent forgetting to insert a nut. Since it is made of resin and has flexibility, its outer periphery is covered with a steel plate 1.
The gap between the cap 5 and the steel plate 1 can be maintained sufficiently watertight simply by crimping the cap 5 to the nut 1.
By crimping the 0, the watertightness of the part can be maintained sufficiently, and as a result, the use of packing can be omitted, simplifying the process and reducing costs.

Further, according to the above device, the threaded rod 8 erected on the tip end face of the temporary bolt 6 which is removably inserted into the bolt hole 2 of the steel plate 1 is passed through the head through hole 9 of the cap 5 and the screw rod 8 is inserted into the bolt hole 2 of the steel plate 1 so as to be inserted into the bolt hole 2 of the steel plate 1. A nut 10 is screwed onto the protrusion from the hole 9 and tightened, and the cap 5 is temporarily fixed so that its outer periphery is crimped to the back surface of the steel plate 1. After concrete is poured, the temporary bolt 6 is attached to the steel plate 1 together with the threaded rod 8. The nut 10 is removed and crimped onto the cap 5 and its head.
By allowing the remaining parts to anchor in the poured concrete, other parts do not protrude from the top surface of the cap 5, and the effective working length Z inside the cap 5 can be increased. There is no need to change the length under the neck of the high tension bolt 14 for main installation in accordance with the change in flange thickness depending on the number of floors of the main steel frame of the building to which the precast concrete member is attached, simplifying workability. It is something that can be done.

Furthermore, according to the device, since the washer 3 is disposed below the nut 4 in the cap 5, the high tension bolt 14 for permanent installation is screwed into the nut 4 and tightened, and the precast concrete member is removed from the other parts. When the steel plate 1 is joined to a member, the presence of the washer 3 reduces deformation of the steel plate 1.

Although the above-mentioned device has many advantages, the temporary bolt 6 is manufactured by machining a normal bolt, so processing accuracy is required, and the screw rod 8 to be attached to the temporary bolt 6 is required. If the machining accuracy is poor, the central axis of the screw rod 8 and the high tension bolt 1 for the main installation will need to be drilled.
4 becomes misaligned, and as a result, the cap 5 becomes misaligned, which in turn causes the nut 4 and washer 3 to become misaligned, making it impossible to perform the intended function.

Furthermore, in the above-mentioned device, the screw rod 8 is tightened with the screw 7 from the side of the temporary bolt 6, so if the screw 7 is not tightened properly, the screw rod 8 will be damaged when removing the temporary bolt 6 after concrete pouring. It may remain and make it impossible to tighten the high tension bolt 14 for permanent installation.

This project was proposed to eliminate such defects, and in a manufacturing device for precast concrete members in which a steel plate is anchored on the surface of the concrete part, bolt holes drilled in the steel plate are installed on the back side of the steel plate. A transparent synthetic resin cap is disposed concentrically with the bolt hole and has a nut and washer slidably fitted in the radial direction of the bolt hole in its inner cavity. A temporary bolt, which is removably inserted into the bolt hole and is fitted with an over-tightening prevention nut that hits the back side of the head when the cap is tightened, is inserted through the washer and nut as well as through the head of the cap. A precast conch notebook characterized in that the outer circumferential edge of the cap is crimped to the steel plate by screwing and tightening a nut to the tip of the temporary bolt that penetrates the hole and protrudes from the head of the cap. This relates to a manufacturing device for parts.

In this case, as described above, instead of installing a threaded rod at the tip of a temporary bolt that is removably inserted into the bolt hole of the steel plate as in the above-mentioned device, the steel plate is inserted so as to cover the bolt hole. After inserting the washer and nut inside the transparent resin cap arranged on the back side, insert the temporary bolt tip directly into the head hole of the cap and insert the nut into the part protruding from the cap. Since the bolts are screwed and tightened, according to this proposal, commercially available bolts can be used as temporary bolts, simplifying the construction of the entire device, and eliminating the need for washers and nuts for high-tension bolts for permanent installation. It can be slidably disposed within the cap with high precision and also saves costs.

Further, in the present invention, an over-tightening prevention nut is attached to the temporary bolt, and when the tightening nut is screwed onto the tip of the temporary bolt protruding from the head through hole of the cap and tightened, the over-tightening prevention nut is attached to the cap. By colliding with the back surface of the head and supporting the tightening force of the tightening nut, the cap is prevented from being deformed due to over-tightening of the tightening nut.

The present invention will be described below with reference to the illustrated embodiments.

A steel plate 21 is to be anchored to the joint surface of the precast concrete member, and a guide plate 23 and a temporary bolt 24 inserted through the plate 23 are inserted into the bolt hole 22 of the steel plate.

The diameter D1 of the insertion portion of the guide plate 23 into the bolt hole 22 is made slightly smaller than the bolt diameter D2, so that the shaft of the temporary bolt 24 inserted through the guide plate 23 when fitted into the bolt hole 22. The center is made to coincide with the axis of the permanent high tension bolt 25 to be inserted into the bolt hole 22.

A washer 26 and a nut 27 for the permanent high-tension bolt are loosely fitted into the temporary bolt 24, and a transparent synthetic resin cap 28 allows the washer 26 and nut 27 to move in the radial direction of the bolt hole 22. It is arranged on the back side of the steel plate 21 so as to cover both of them, and the tip of the temporary bolt 24 is passed through the head through hole 29, and the nut 30 is screwed into the protruding end of the temporary bolt 24. The peripheral edge of the cap 28 is crimped to the back surface of the steel plate 21.

Note that if the nut 30 is tightened too strongly, there is a risk that the plastic cap 28 may be deformed. Therefore, an over-tightening prevention nut 31 is attached to the temporary bolt 24 in advance, and the nut 30 is tightened to remove the cap 28. When the steel plate 21 is watertightly crimped, the cap 28 is tightly fitted between the nut 30 and the over-tightening prevention nut 31, so that the cap 28 cannot be tightened any further.

Next, concrete 32 is placed on the back surface of the steel plate 21, and after the poured concrete 32 has hardened, the temporary bolt 24 is removed while being rotated.

At this time, the cap 28 is restrained by the concrete 32 and does not move.

When friction welding the steel plate of the precast concrete member manufactured in this way to the steel plate 33 of another member, the high tension bolt 25 for permanent installation is attached to the steel plate 33 so that the washer 34 is interposed between the head of the bolt. Further, the tip thereof is inserted into the bolt hole 22 of the steel plate 21 and the washer 26, and then screwed onto the nut 27 and tightened.

At this time, since the nut 27 is movable in the radial direction of the bolt hole 22, even if the steel plate 21 and the steel plate 33 of another member are misaligned due to construction errors, this error is absorbed, and both of them are It is tightened on the same axis as the central axis of the tension bolt 25.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a conventional precast concrete member manufacturing apparatus, and FIG. 2 is a longitudinal sectional view of an embodiment of the precast concrete member manufacturing apparatus according to the present invention. 21... Steel plate, 22... Bolt hole, 24... Temporary bolt, 26... Washer, 27... Nut, 28...
Cap, 29...Through hole, 30...Nut, 31.
・Over-tightening prevention nut.

Claims (1)

[Scope of utility model registration request] In an apparatus for manufacturing a precast concrete member in which a steel plate is anchored on the surface of a concrete part, a bolt hole drilled in the steel plate is placed on the back side of the steel plate, and the bolt hole is arranged concentrically with the bolt hole, and the inner cavity thereof is A transparent resin cap is disposed in the bolt hole, and a nut and a washer are slidably and loosely fitted in the radial direction of the bolt hole, and the cap is inserted into and removably into the bolt hole, and the cap is tightened. At the same time, insert a temporary bolt fitted with an over-tightening prevention nut that should come into contact with the back side of the head into the washer and nut as well as the head hole of the cap, and insert the temporary bolt that protrudes from the head of the cap. An apparatus for manufacturing a precast concrete member, characterized in that a nut is screwed onto the tip of a bolt and tightened, and the outer peripheral edge of the cap is crimped to the steel plate.