JPH0446889Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an inner formwork for forming a hollow part of a concrete hollow body such as a concrete hollow column.

[Conventional technology]

In general, the inner formwork that forms the concrete hollow body is made of plywood or corrugated cardboard. Examples of the latter include, for example,
No. 60-2897 (see Figures 7 and 8).

The above-mentioned inner formwork includes a core plate 32 having a plurality of slots 31 formed on the outer periphery, and can be wound outwardly along the outer periphery of the core plate 32, and has insertion slots 33 formed at regular intervals in the longitudinal direction of both ends. The ends of the outer winding plates 34 and 35 are connected to the core plate 3.
The structure is formed by fitting into the slot 31 of No. 2.

However, in the above inner formwork, the core plate 32 is
4 and 35, the pressure resistance is not sufficient, and if the inner form is subjected to external pressure in the direction of twisting, the slot 31
Also, there are problems in that the force is concentrated on the insertion slot 33 portion and it is easily broken, and since the core plate 32 has a plurality of slots 31, the strength of the core plate 32 is weakened and easily deformed. Furthermore, the conventional inner formwork described above has a structure that cannot be assembled unless the slots 31 of the plurality of core plates 32 are fitted into the plurality of insertion slots 33 of the outer winding plate 34 or 35 at the same time. Assembly was extremely complicated and workability was poor.

[The problem that the idea attempts to solve]

The purpose of this invention is to solve the above-mentioned drawbacks of the conventional inner formwork, strengthen the pressure resistance of the core plate of the inner formwork for forming the hollow part of hollow concrete bodies, and improve the workability of assembly. be.

[Means for Solving the Problems] In order to solve the above problems, in this invention, two sets of opposing edges of a pair of opposing corrugated polygonal core plates are connected by a side wall to form a plurality of ring-shaped members. A plurality of ring-shaped members are arranged in a column with the core plates adjacent to each other, and a plurality of ring-shaped members are arranged on both sides of an outer wrapping plate made of corrugated cardboard that can be wound outwardly along the outer periphery of the core plate. The tongue piece is formed into a comb-teeth shape, and the tongue piece is fitted inside each of the side walls.

[Effect]

The inner formwork for forming the hollow part of a concrete hollow body according to this invention has two core plates arranged adjacent to each other to reduce stress on each core plate due to external pressure, thereby preventing deformation of the core plates. Ru. The plurality of ring-shaped members are prevented from deforming by inserting tongues of outer wrappers inside the side walls, and since the opposing positional relationship of each core plate does not change, the inner formwork described above does not twist. It is difficult to change the state. Moreover, the inner formwork can be assembled by simply arranging the ring-shaped members in a column and inserting the tongue pieces of the outer winding plate.

〔Example〕

An embodiment of this invention will be described below based on FIGS. 1 to 6.

As shown in FIGS. 1 and 2, the inner formwork for forming the hollow part of the concrete hollow body has two corrugated heptagonal core plates 1 facing each other, and two sets of opposite edges are connected to each other by side walls 2. A plurality of ring-shaped members 3 are formed by connecting with each other, and the plurality of ring-shaped members 3 are arranged in tandem with the core plates 1 adjacent to each other, and a plurality of tongue pieces 4 are provided in a comb-teeth shape on both side edges. The tongue pieces 4 of the outer winding plates 5 and 6 are respectively inserted into the inner side of the side wall 2 and wound outward.

As shown in FIG. 3a, the blank of the ring-shaped member 3 is constructed by connecting the edges of a pair of two core plates 1 to each other by a rectangular side wall 2, and A separate side wall 2 is connected to one edge of the side wall 2 on the side opposite to the connecting side, and an adhesive piece 7 to be stuck and fixed to this side wall 2 is connected to the other edge, and each connected portion is connected to the side wall 2. The fold line 8 is formed. Ring-shaped member 3
The above-mentioned blank is folded at each fold 8, and the adhesive piece 7 is pasted on the inside of the side wall 2 with an adhesive, adhesive tape, etc., and assembled into the state shown in FIG. 2. The core plate 1 of this ring-shaped member 3 may have a polygonal shape other than the heptagonal shape described above, and the size of the side wall and the arrangement of the two sets of opposing edges connected thereto may be determined by the inner mold to be assembled. Any suitable choice can be made as long as the frame has sufficient pressure resistance.

As shown in FIGS. 3b and 3c, the blanks of the outer corrugated cardboard sheets 5 and 6 are formed with the required length of the inner formwork in the lateral direction in the figure, with folds 5a and 6 in the same direction.
In the longitudinal direction of the figure, a ring-shaped member 3 is formed with a width that allows two or three end edges of the core plate 1 to be wound outward. Further, on both side edges of these blanks, a plurality of tongue pieces 4 having a width to be inserted into the inside of the side wall 2 are formed in a comb-teeth shape.
In this case, if the spacing between the tongues 4 is such that the two adjacent core plates 1 can be sandwiched between them, the core plates 1 will come into close contact with each other during assembly as shown in FIG. 4.

Further, as shown by the chain line in FIG. 2, a slot 9 is formed on the outer periphery of the core plate 1, and fitting slots 10 that engage with the slot 9 are formed at regular intervals in the longitudinal direction of one side edge. A cross plate 11 may be provided, the ring-shaped member 3 may be assembled to the cross plate 11, and one or more exterior plates 12 may be further provided to cover the entire circumference of the inner form.

The above-described embodiment configured in this manner is assembled and used as follows.

As shown in FIG. 2, first, the core plate 1 is placed adjacent to the insertion slot 10 of the cross plate 11 and the ring-shaped member 3 is attached, and then the outer plate 5 is placed below and the tongue piece 4 is attached. It is made to stand up, and the tongue pieces 4 are sequentially inserted into the inside of the side wall 2.
Next, the other outer winding plate 6 is inserted from above by inserting the tongue piece 4 in the same manner as described above, and assembled into the state shown in FIGS. 1 and 5. When assembled in this manner, the ring-shaped members 3 can be easily assembled adjacent to each other by the crosspiece 11, so there is an advantage that the assembly can be performed extremely easily.

The inner formwork has core plates 1 located at both ends in the longitudinal direction, and there is no need to separately provide caps to cover both ends. Concrete intrusion is prevented. It goes without saying that it is preferable to impart water repellency to the cardboard material by various methods such as film lamination and coating.

This inner formwork is the outer formwork 1 of the concrete hollow body in which the hollow part is to be formed, as shown in FIG.
3, fill the surrounding area with fresh concrete and dry it to form a concrete hollow body 14.
is formed.

〔effect〕

As is clear from the above explanation, in the inner formwork for forming the hollow part of the hollow concrete body of this invention, the core plates are adjacent to each other, so the pressure resistance of the core plate is strengthened, and the ring-shaped member is Since the core plate is fixed in position by being held by the winding plate, the inner form is difficult to deform into a twisted state, and has the advantage of being extremely easy to assemble.

[Brief explanation of the drawing]

1 to 6 show examples of this invention,
Fig. 1 is a perspective view, Fig. 2 is an exploded perspective view illustrating the assembled state, Fig. 3 is a developed view, Fig. 4 is a vertical sectional view taken along the - line of Fig. 1, and Fig. 5 is a - line of - of Fig. 1. 6 is a cross-sectional view illustrating the state of use, FIGS. 7 and 8 show a conventional example, FIG. 7 is an exploded perspective view, and FIG. 8 is a cross-sectional view. 1... Core plate, 2... Side wall, 3... Ring-shaped member, 4
... Tongue piece, 5, 6 ... Outer plate.

Claims (1)

[Scope of utility model registration request] A plurality of ring-shaped members are formed by connecting two sets of opposing edges of a pair of opposing corrugated polygonal core plates with a side wall, and the plurality of ring-shaped members are arranged in tandem with the core plates adjacent to each other. , a plurality of tongue pieces are formed in a comb-teeth shape on both side edges of an outer wrapping plate made of corrugated cardboard on which the plurality of ring-shaped members can be wound around the outer periphery of the core plate, and the tongue pieces are placed inside each of the side walls. Inner formwork for forming the hollow part of a concrete hollow body, which is formed by inserting each part.