JPS6130812Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of a formwork for centrifugal forming of concrete products such as concrete piles, concrete poles, and humid pipes.

Conventionally, this type of molding form (Utility Model Publication No. 53-23729
As shown in FIG. 1, which shows a vertical cross section of the main part, the system is formed of a semi-cylindrical lower frame 1 and an upper frame 2, and the outer surfaces of the lower frame 1 and the upper frame 2 are , a pair of flanges 3 and 4 are provided close to the edge thereof, a gate-shaped wedge receiver piece seat 5 is fixed to the flange 3 of the lower frame, and a wedge receiver piece insertion hole 6 is provided;
A gourd-shaped through hole 7 is provided in the flange 4 of the upper frame, and a wedge piece 8 having a pronged end that sandwiches the small diameter hole of the through hole 7 is welded to the upper frame. Across the through hole 7 and the wedge receiving piece through hole 6 of the lower frame,
The head body 9 of the screw rod 9 is inserted into the wedge receiving piece 10, which is formed into an oval shape in plan, and the nut 11 is screwed onto the screw rod 9.
12 is fixed to the wedge receiver single seat 5, and by sliding the upper frame 2 and the lower frame 1 in the longitudinal direction, the wedge piece 8 is press-fitted to the lower side of the head body 9, and the upper frame 2 and the lower frame are The frame 1 is tightened via flanges 3 and 4.

However, in such a conventional molding form, the flanges 3 and 4 are simply tightened with the lower frame 1 and upper frame 2 in close contact with each other as shown in the figure. When the concrete is rotated at high speed during molding of concrete products, a part of the fresh concrete flows out from the abutment part 13 between the upper frame 1 and the lower frame 2 due to centrifugal force, and this flows out from the gap between the flanges 3 and 4 to the outside. This will result in spillage and scattering.

In order to improve this drawback, it is possible to interpose a packing such as elastic rubber or gasket between the flanges 3 and 4, but in reality, the gap h between the flanges 3 and 4 when tightening is about 2 mm. Moreover, since the upper frame 1 and the lower frame 2 are tightened by sliding in the longitudinal direction, it is hard to say that the effect of interposing the seal in preventing leakage is sufficient.

In other words, it is very difficult to install the packing because it is made of rubber, and the life of the packing is extremely short due to wear and damage to the packing due to repeated use of sliding in the longitudinal direction between the upper frame 1 and the lower frame 2. Because they are short and time consuming to replace, resulting in high maintenance costs, they have not been put into practical use. Also, in order to prevent concrete from flowing out, it is effective to increase the thickness of the packing, but
The upper frame 1 and the lower frame 2 may not slide properly.

This invention attempts to solve the above-mentioned conventional drawbacks, by placing a metal plate between the flanges, fixing this to the flange of the lower frame by spot welding, and tightening the flange by sandwiching the metal plate. Due to the width and elasticity of the metal plate, ready-mixed concrete does not flow out, and it is very durable, and the tightening work between the lower frame and the upper frame, that is, the sliding work between the upper frame 1 and the lower frame 2, is smooth. We are trying to make it possible.

An embodiment of this invention will be described below with reference to FIGS. 2 and 3.

Figure 2 is a vertical cross-sectional view showing the main parts of the centrifugal molding form according to this invention, and Figure 3 is an enlarged vertical cross-sectional view showing how the metal plate is attached. The same parts as the formwork are given the same reference numerals.

As is clear from the figure, the centrifugal molding form of this invention also has a semicircular lower frame 1, similar to the conventional form.
and an upper frame 2, each having flanges 3 and 4. A gate-shaped wedge receiver piece 5 is fixed to the flange 3 of the lower frame, and a wedge receiver piece 10 is attached to this by nuts 10 and 11. is fixed. This wedge support piece 10
is a wedge that projects upward through the flange 3 of the lower frame from the gourd-shaped through hole 7 of the flange 4 of the upper frame, and is formed and fixed to the lower side of the head body 9 so as to sandwich the small diameter hole of the through hole 7. Piece 8 is press-fitted.

A relatively soft metal such as soft iron or copper alloy is used on the upper surface of the inner side of the wedge receiving piece insertion hole 6 of the flange 3 of the lower frame over almost the entire length of the flange 3 in the longitudinal direction. A thin and wide metal plate 14 is fixed thereto. As shown in FIG. 3, this metal plate 14 is attached by partially welding 15 to the flange 3 on the outer side, for example.
Just do it. If only one side of the metal plate 14 is to be fixed in this way, the metal plate 1
Not only is it easy to install, repair, or replace the metal plate 4, but because only one side of the metal plate 14 is welded, the other side floats upward as shown in FIG. The flange 3,
The tightening effect of 4 is improved, and the flange 3,
4 and the metal plate 14 become close to each other.

As explained above, in this invention, since the metal plate 14 is fixed to the upper surface of the flange 3 of the lower frame, the tightening by the flanges 3 and 4 is performed elastically, and the Each surface is in close contact with the metal plate 14 over a wide area, and the fresh concrete poured into the upper and lower frames 1 and 2 during centrifugal forming is transferred to the abutment area 13 of the upper and lower frames 1 and 2. The metal plate is extremely strong and durable, and the metal plate is extremely strong and has excellent durability. Not only is it suitable for tightening type forms, but it can also be applied to other forms in which flanges are simply tightened from above and below with bolts, nuts, etc., resulting in formworks with excellent workability and economy. It has many advantages, such as the ability to

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view showing the main parts of a conventional formwork, Fig. 2 is a longitudinal sectional view of the main part of a formwork showing an embodiment of this invention, and Fig. 3 shows how the metal plate is attached. It is an enlarged longitudinal cross-sectional view. 1... Lower frame, 2... Upper frame, 3, 4... Flange, 5... Wedge receiver piece seat, 6... Wedge receiver piece insertion hole, 7...
...Through hole, 8...Wedge piece, 9...Head body, 10...Wedge receiver piece, 11, 12...Nut, 13...Abutment part,
14...Metal plate, 15...Welding.

Claims (1)

[Scope of utility model registration request] A centrifugal mold for centrifugal molding, in which a pair of flanges 3 and 4 are provided on the outer surfaces of a semi-cylindrical lower frame 1 and an upper frame 2 close to their edges, and these flanges 3 and 4 are tightened together. A formwork for centrifugal forming of concrete products, characterized in that a metal plate 14 is fixed to the upper surface of a flange 3 of a lower frame by point welding along its length.