JPS597952Y2 - Frame for drilling into concrete structures - Google Patents

Description

[Detailed explanation of the invention] This invention is designed to bury anchor bolts, guardrail poles, and other columnar objects vertically in a concrete structure by forming blind holes from the top to the inside. The present invention relates to a perforation frame.

The present invention consists of a cylindrical frame body that is open at the top and a lid that fits into the upper opening of the frame body, and the head of the frame body is provided with an engaging part such as a brim. A small hole for air venting is provided in the bottom surface and the lid of the frame body, and the frame body is buried vertically with the head portion of the frame body partially protruding into the concrete at the time of pouring, and after the concrete hardens, an external extraction means is provided. The target blind hole is drilled by locking a hook or the like on the retaining part of the frame body and pulling it out.

Hereinafter, one embodiment of the present invention will be explained in detail with reference to the drawings.

Figure 1 shows an example of a case where a blind hole for embedding a guardrail pole, etc. is to be drilled in a band-shaped concrete structure formed on both sides of the tread of a bridge. The perforation frame 1 of the invention consists of a cylindrical frame body 2 with an upper opening, for example, and a lid 3 that fits into the upper opening.

The material of this frame body 2 is not particularly limited, but it is preferably made of a material that has sufficient strength to withstand the pressure of concrete and does not have adhesive properties with concrete. The head part is provided with a retaining part 4 having an enlarged diameter, for example, in the shape of a brim, and a small hole 5 for air venting is provided in the bottom surface of the retaining part 4.

More preferably, the frame body 2 should have a tapered surface 2a whose diameter increases slightly but gradually from the bottom to the top so that it can be easily pulled out. It is preferable to provide reinforcing ribs 6 at appropriate intervals between the joint lower surface bases.

The lid 3 is made of plastic, for example, and is fitted into the upper opening of the frame body 2 to prevent unnecessary objects from entering inside and to prevent the frame body from being crushed when pulled out. As shown in FIGS. 1 and 2, a knob 7 is protruded from the center thereof, and a small hole 8 for venting air is provided on the upper surface thereof.

In order to drill a blind hole from the top surface to the inside of a concrete structure using the drilling frame 1 having such a structure, first, as shown in FIG. Before the concrete poured between the frames 9, 9 is yet hardened, the perforating frame 1 is vertically pressed and buried with its head partially protruding from the concrete surface.

In this case, a mold release agent or the like having good releasability to concrete may be applied to the outer periphery of the body of the frame body 2, if necessary.

Then wait for the concrete to harden. Once the concrete has hardened sufficiently, as shown in Figure 3, the external pulling means 1
0, for example, using a type of hydraulic jack, its hydraulic mechanism 1
1, the lifting rod 1 moves up and down centering on the other support member 12.
Hook 14.14 hanging down from 3 is hooked onto the retaining part 4 of the head protruding above the concrete surface, and then the lever 15 of the hydraulic mechanism 11 is operated to rotate the lifting rod 13 upward, Gradually pull out the perforation frame 1.

During this extraction, a space is formed below the blind hole by the rise of the frame 1, but in this space there are small holes 5 for removing the space,
Since external air is supplied from 8, there is no vacuum, and the extraction is performed smoothly.

In addition, when the outer circumferential surface of the body part of the frame body 2 is tapered as the tapered surface 2a as described above, by the initial slight pulling out,
You can easily pull it out afterwards.

In this way, when the drilling frame 1 is completely withdrawn, the desired blind hole 16 can be formed in the concrete structure 17.

Therefore, it is sufficient to insert the lower end of an anchor bolt, pole, etc. into the blind hole 16, fill it with concrete, and allow it to harden.

As described above, according to the drilling frame according to the present invention, it is possible to easily and accurately make blind holes for vertically burying anchor bolts, guardrail poles, and other columnar bodies in concrete structures. The practical effects are enormous.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal side view showing the drilling frame according to the present invention embedded in concrete, Fig. 2 is a plan view of the drilling frame, and Fig. 3 shows the drilling frame in its pulled out state. FIG. 2 is a partially longitudinal side view showing an example. 1... Frame for drilling, 2... Frame body, 3
...Lid body, 4...Engagement part, 5, 8...
...Small hole for air vent.

Claims (1)

[Scope of utility model registration request] It consists of a frame body with an upward opening, which is buried in the concrete during pouring with the head partially protruding, and a lid body that fits into the upper opening of the frame body, and the head of the frame body is buried in concrete. A body for drilling into a concrete structure, characterized in that an engaging part is provided with which a hook or the like of an external extraction means engages after hardening, and a small hole for air venting is provided in the body and the lid. .