JPH028011A - Concrete form device of centrifugal concrete molder - Google Patents

Abstract

PURPOSE:To produce a hollow dense column excellent in strength without employing a double concrete form by a method wherein a concrete form having a rectangular cross-section is supported by discs and turning force is given to the turning wheel or driving wheel of a centrifugal concrete molder. CONSTITUTION:A concrete form device 1 consists of a concrete form 2 having a rectangular cross-section, which is constituted by generally and strongly assembling panels into a cube having quadrilaterals, discs 3, in each of which an opening to fit the concrete form therein is bored, and bars 4, which are inserted in the concrete form 2. The discs 3 are respectively fitted to both the ends of the concrete form 2 under the condition that the axial center of the concrete form coincides with the center of each disc 3. The concrete form 2 is turned by turning the discs 3. A centrifugal concrete molder 7 has turning wheels 8 and 8a. The turning wheel 8 is connected with a belt 11 to a driving wheel 10. In order to manufacture a hollow square column, the concrete form device 1 is installed horizontally with the portions of the discs thereon. After that, concrete is charged in the concrete form 2. After the near solidification of the concrete, the molder 7 is stopped for demolding.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a formwork for a centrifugal concrete forming machine for obtaining a column having a hollow rectangular cross section and onto which main reinforcing bars can be installed later. Regarding equipment.

(Prior Art) In recent years, precast concrete has been used in high-rise buildings because of its high construction efficiency for reinforced concrete structures and its ability to produce high-quality concrete products.

Increasingly, precast concrete hollow columns are being used to connect the column/beam joints of precast concrete columns and the columns together in the axial direction.

Such hollow columns are generally made using a centrifugal concrete forming machine, and when concrete is poured into the formwork while rotating, the concrete adheres tightly to the inner wall of the formwork due to centrifugal force. It is cured as it is to obtain a hollow column.

The above-mentioned formwork was generally of a cylindrical type because it was rotated.

(Problem to be solved by the invention) However, building columns are usually formed with a rectangular cross section, and there has never been one in which a cubic column form is rotated using a centrifugal forming machine. .

The present invention has been made in view of the circumstances described above, and
The object is a precast hollow column with a rectangular cross section, and a centrifugal concrete forming machine that forms it so that reinforcing bars of any shape and length can be later installed to facilitate connection with other members. to provide formwork equipment.

(Means for Solving the Problems) In order to achieve the above object, a formwork device for a centrifugal concrete forming machine according to the present invention includes a centrifugal concrete forming machine equipped with a drive wheel for rotating a horizontally placed formwork. The formwork of the machine consists of a box-like formwork with a rectangular cross section, a disk attached to the center axis of the formwork, and a rod passed through the formwork in the axial direction. The formwork was made to rotate by receiving the rotational output of the drive wheel by the disk.

(Function) The box-shaped formwork with a rectangular cross section and the disk are concentric,
When this disk is rotated, the formwork also rotates and an even centrifugal force acts inside the formwork. When concrete is poured into the formwork while rotating, the centrifugal force presses the concrete closely against the inner walls of the formwork and solidifies it.

At this time, the rods that have been inserted into the formwork in advance are held at corner positions within the formwork by the action of centrifugal force, and are fixed in that position by the poured concrete.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an outline of the formwork device 1. This formwork device 1 includes a formwork 2 with a rectangular cross section that is constructed by firmly assembling panels into a square cube shape, a disk 3 with an opening into which it is inserted, and a disk 3 that is inserted into the formwork 2. It consists of a rod 4 having a right triangular cross section.

The formwork 2 needs to have sufficient strength to withstand the centrifugal force of concrete thrown into it during rotation. And this formwork 2
Place the formwork 2 in such a way that the axial center of the disk 3 matches the center of the disk 3.
Discs 3 are fitted on each end of the disc.

By rotating the disk 3, the formwork 2 is rotated.

Furthermore, four rods 4 having a right triangular cross section are placed in the formwork 2 in advance.
Insert the book. This is placed in the corner of the formwork 2 by the centrifugal force generated when the formwork 2 is rotated.

The details are shown in FIG. 2 in the direction indicated by the arrows ■-■ in the figure.

In the formwork 2, a hoop line 6 is arranged with a doughnut-shaped spacer (commonly known as a donut) 5 fitted thereinto at an appropriate distance from the inner wall surface of the formwork 2.

FIG. 3 shows the centrifugal concrete forming machine 7 and the above-mentioned formwork device 1 together. It is connected by a belt 11 to a drive wheel 10 attached to the output shaft of a motor 9.

Therefore, when manufacturing a hollow prismatic column, the formwork device 1 is placed horizontally with the disk 3 placed between the rotating wheels 8-8a of the molding machine 7.

Then, concrete is poured into the formwork 2, and both end faces of the formwork 2 are closed. To close the formwork, an iron plate or plate material is screwed to the side of the formwork 2.

Concrete may be poured from the side of the formwork 2, or from a closable opening provided in a part of the formwork 2, but the concrete may be poured from the center of the iron plate that closes the side end face of the formwork 2. A concrete pressure hose is rotatably connected to the formwork 2.
After rotating the rod 4 and moving it to the corner by centrifugal force, concrete is poured in while further increasing the rotational speed.

Centrifugal force causes the concrete to coagulate and excess water drains from the edges of the formwork. It is desirable to drain as much excess water as possible during rotation to obtain high quality concrete.

When the concrete is almost solidified, the centrifugal concrete molding machine 7 is stopped and the concrete is demolded. After demolding, a product as shown in FIG. 4 is obtained. This is a square prism 12 that has a cylindrical space inside due to centrifugal force.

Its four corners are provided with spline-shaped notches 13 with a rectangular cross section obtained by extracting the rod 4 from behind. The column main reinforcement 14 can be passed along this notch 13. Note that if the surface of the rod 4 is coated with a Teflon coating, or an edge cutting agent such as oil or fat is applied, it will be easier to remove it later.

Next, another embodiment of the present invention will be described.

FIG. 5 is an end view of the same part as shown by the arrows ■-■ in FIG. In comparison, it is almost the same as the previous embodiment except for the fan shape, so only the differences will be described below.

First, a rod 4a with a fan-shaped cross section is installed in the mold crusher 2, and the mold 2 is rotated while inserting concrete into the mold 2 so that the short side thickness a of the square pillar 12a becomes the required thickness. .

In figure (1) of the same figure, when the concrete has hardened to some extent, the thickness b of the long side of the square column 12a becomes thinner, so the formwork 2 is added while adding concrete so that this part has the required thickness. Rotate it (Figure (2)).

Figure (3) in the same figure is the same figure (2) after the concrete hardens.
A square column 12a having a rectangular cross section and having notches 13 spaces at the four corners, which is obtained by demolding the rod body 4a having a fan-shaped cross section and the formwork 2.
of products are obtained.

(Effects) As explained in detail above, according to the formwork device of the present invention, the formwork configured to have a rectangular cross section is supported by a disk at a coaxial center position, so that Since rotational force can be applied by placing the disk part of the formwork on the drive wheel, it is possible to create a shape with a rectangular cross section that is dense and strong, without using a double formwork with an inner formwork etc. A hollow column can be formed.

In addition, since the rod is inserted into the formwork and placed in the corner using centrifugal force, there is no need to specifically lock it in the formwork, making it easy to remove it after concrete is poured. do. Furthermore, in the notch that remains after the rod is removed, there is a column main reinforcement of any length depending on the site situation, and the diameter can be selected arbitrarily and the reinforcement can be arranged with an appropriate concrete cover thickness, so the column reinforcement・It is convenient for joining beam joints, and can provide a column body that is ideal for construction using precast concrete.

Furthermore, it is also possible to form a hollow column with a rectangular cross section, and by selecting the cross-sectional shape of the bar, the notches formed at the corners of this hollow part can be made into the optimal shape for passing the main reinforcement. effective.

[Brief explanation of the drawing]

The drawings all relate to embodiments of the present invention, and Fig. 1 is a perspective view showing a formwork device of a centrifugal concrete forming machine, Fig. 2 is an end view shown along the line of arrows ■-■ in Fig. 1, and Fig. 3. is a side view illustrating the state in which the formwork device is placed in the centrifugal concrete forming machine;
FIG. 4 is a perspective view illustrating a hollow columnar body obtained by the present invention, and FIG. 5 is a cross-sectional view of a formwork device according to another embodiment, and also describes the process of its use (1) to (3). FIG. 10... Drive wheel 12... Square column 14... Column main reinforcement 11... Belt 13... Notch

Claims (1)

[Claims] (1) The formwork of a centrifugal concrete forming machine is equipped with a drive wheel for rotating the formwork placed horizontally. Centrifugal concrete molding comprising an attached disk and a rod passing through the formwork in the axial direction, and the formwork is rotated by receiving the rotational output of the drive wheel by the disk. Machine formwork equipment.