JPH03324Y2 - - Google Patents

Description

[Detailed description of the invention] Purpose of the invention Industrial application field This invention is intended for the purpose of manufacturing holes in various concrete products, such as holes used for connecting concrete products, holes used for lifting, holes used for water drainage, and holes used for collecting water. It relates to a formwork structure for forming.

BACKGROUND ART When connecting concrete products such as gutter blocks and box culverts, connecting pins 29 having tapered sides on both sides are used as shown in FIG. In this case, the concrete product C is provided with a hole for inserting the connecting pin, but the lower hole 25 is provided horizontally, whereas the upper hole 24 is provided at right angles to the slope 30, that is, with respect to the horizontal direction. It is installed at an angle.

To form such a hole, a truncated cone-shaped protrusion is made to protrude from the inner surface of the formwork, but if the protrusion is inclined with respect to the demolding direction of the formwork, the protrusion should be removed prior to demolding. must be removed.

FIG. 4 is a schematic sectional view showing a formwork for concrete product C. When removing the mold by folding down the side plate 27 using the hinge 28, the lower protrusion 26 coincides with the removing direction (direction of arrow A); The upper projections do not match. Therefore, the upper protrusion is formed by screwing the male threaded part 23 of the bolt 21 into the nut 20 welded and fixed to the outside surface of the mold, and making the tip 22 protrude from the inside of the mold. is removed.

FIG. 7 is a sectional view of a connecting portion of the wall panel 31, in which two wall panels are connected by passing bolts 33 through through holes 32 and tightening them.

FIG. 6 is a partial sectional view of the formwork of the wall panel 31. When removing the mold by folding down the side plate 38 using the hinge 39, the length of the through hole is long and the taper of the through hole is small even though the distance h between the hinge 39 and the through hole is short. The protrusion for forming must be removed. Therefore, this protrusion is formed by screwing the male threaded portion 36 of the bolt 35 into a nut 34 welded to the outer surface of the mold, and causing the tip 37 to protrude into the inner surface of the mold.

Problems that the invention aims to solve: The formwork structure that forms the holes in concrete products as described above is complicated and difficult to install and install by rotating the bolts with an impact wrench each time the formwork is demolded or assembled. There was also the problem that leaked concrete adhered to the threaded parts of bolts and nuts, causing damage to those parts.

This invention solves these conventional problems and
The present invention provides a formwork structure for forming holes in concrete products that has excellent work efficiency during demolding and assembly of formwork, and is less affected by concrete leakage.

Means for solving the structural problems of the invention The present invention consists of a ring which is fixed to the outer surface of the formwork, has a cylindrical shape with the rear part having a socket-like diameter increased compared to the front part, and which is fixed by suction inside the rear part. A male member having a truncated conical head and an integrally formed flange plate having means for engaging with an inverted hammer at the tail is inserted into a female member having a shaped magnet, and the head is made to protrude into the formwork. ,
This formwork structure for forming holes in concrete products is characterized by fixing a male member to a female member by the attraction force of a magnet acting on a flange plate.

Function This invention utilizes the attraction force of a ring-shaped magnet that fits into a cylindrical female member fixed to the outer surface of the formwork, makes its head protrude inside the formwork, and is fixed to the rear of the female member. Since the male member is fixed by acting on the flange plate of the male member, attachment and detachment of the male member is extremely easy. In other words, when installing, just fit the male member into the female member and it will be fixed by the attraction force of the magnet, and when removing it, engage the flange plate with a reverse hammer and pull it out, so there is no need to rotate the bolt. Since it does not have a threaded part, cleaning for concrete leakage is also easy. The reason why the head of the male member is shaped like a truncated cone, that is, tapered so that the diameter becomes smaller toward the tip, is because
A so-called draft angle is provided to facilitate the removal of the male member during demolding.

By creating a gap (approximately 1 to 3 mm) between the outer peripheral surface of the magnet and the inner surface of the rear peripheral wall of the female member, and a small gap (approximately 0.3 to 1 mm) between the magnet and the flange plate of the male member, the attraction force of the magnet will be reduced. It acts most efficiently on the flange plate and securely fixes the male member.

Embodiment Fig. 1 is a sectional view showing an embodiment of the structure of the present invention, Fig. 2 is a side view showing the state in which the male member is pulled out, and Fig. 3 is a side view showing another example of the means for engaging with the inverted hammer. It is a diagram.

As shown in FIG. 1, a cylindrical female member 1 is fixed to the outer surface of a formwork 12 by welding. The rear part 1b has a socket-shaped diameter increased compared to the front part 1a,
Inside, there is a ring-shaped magnet 8 which is magnetically attracted and fixed to the inner side of a step 3 formed around the end face 2. There is a distance of 2 mm between the outer peripheral surface of the magnet 8 and the inner surface of the rear peripheral wall of the female member.
There is a gap 9. The male member 4 has a head 5 formed in the shape of a truncated cone, a flange plate 6 integrally formed at the tail, and an intermediate portion thereof formed into a slightly constricted rod shape without contacting the magnet 8 and the inner circumferential surface of the female member. This increases the attraction power of the magnet. 11 is a seal ring to prevent concrete leakage. Flange plate 6
An annular notch 6a is formed on the outer periphery to engage with the rear end of the female member 1 to stabilize the male member 4, and a reverse hammer engaging portion 7 having an annular bulge 7a is integrally formed on the back surface. There is. The male member 4 is fitted into the female member 1, the head 5 protrudes into the mold 12, and the flange plate 6 contacts the rear end of the female member. At this time, a gap 10 of 0.5 mm is created between the magnet 8 and the flange plate 6.

To remove the male member 4 from the female member 1, as shown in FIG. Pull it out.

Various engagement portions of the male member with the inverted hammer can be considered depending on the shape of the head of the inverted hammer. for example,
As shown in FIG. 3, in the case of a hook-shaped head 16,
These include a hook-shaped engaging portion 17 shown in A, a round annular engaging portion 18 shown in B, and a perforated plate-like engaging portion 19 shown in C.

When the male member 4 is removed and the formwork 12 is demolded, a hole similar in shape to the head 5 of the male member is formed in the concrete surface.

Effects of the invention With this invention, it is possible to attach and detach the male member extremely easily and in a short time when demolding and assembling the formwork, and since there are no screws, it is easy to clean even if concrete leaks. Is possible. The present invention is suitable for forming holes in various concrete products, such as holes used for connecting concrete products, holes used for lifting, holes used for draining water from retaining walls, etc., and holes used for collecting water from waterways, etc. It is practically excellent.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the structure of the present invention, FIG. 2 is a side view showing the male member pulled out, and FIG. 3 is a side view showing another example of the means for engaging with the reverse hammer. Fig. 4 is a sectional view showing the structure of a conventional tapered hole forming part, Fig. 5 is a sectional view showing the concrete product connection state, Fig. 6 is a partial sectional view of the formwork of the wall panel, and Fig. 7 is the wall panel. FIG. 1...Female member, 1a...front part, 1b...rear part,
2...End face, 3...Step part, 4...Male member, 5...
Head, 6...flange plate, 7...engaging portion, 8...
Magnet, 9...Gap, 10...Gap, 11...Seal ring, 12...Formwork, 13...Inverted hammer,
14...Head, 15...Floating weight, 16...Head,
17, 18, 19... engaging portion, 20... nut,
21...Bolt, 22...Tip, 23...Male thread, 24, 25...Hole, 26...Protrusion, 27...
...Side plate, 28...Hinge, 29...Connecting pin, 3
0...Slope, 31...Wall panel, 32...Through hole, 33...Bolt, 34...Nut, 35...
Bolt, 36...Male thread part, 37...Tip part, 3
8...Side plate, 39...Hinge.

Claims (1)

[Claims for Utility Model Registration] (1) It is fixed to the outer surface of the formwork, has a cylindrical shape with the rear part having a socket-like diameter increased compared to the front part, and has a ring-shaped magnet that is attracted and fixed in the rear part. To the female member,
A male member having a truncated conical head and an integrally formed flange plate having a means for engaging with an inverted hammer at the tail is inserted, the head protrudes into the formwork, and a magnet acting on the flange plate is inserted. A formwork structure for forming holes in concrete products, which is characterized by fixing a male member to a female member by suction force. (2) By adsorbing and fixing the ring-shaped magnet in the step formed around the rear end of the female member, a gap is secured between the outer peripheral surface of the magnet and the inner surface of the rear peripheral wall of the female member, and the flange plate of the male member is secured at the rear of the female member. A formwork structure for forming a hole in a concrete product according to claim 1, wherein a slight gap is formed between the flange plate and the magnet when the magnet is completely fitted in contact with the end thereof.