JPS602895Y2 - Formwork for concrete products using centrifugal force forming - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a formwork for concrete products by centrifugal force forming.

Usually, the formwork for centrifugal force forming of concrete products is
As shown in Figures 1 and 2, it consists of a semicircular upper formwork 1 and a lower formwork 2 which are made by dividing a hollow circular steel pipe into two parts. For example, a pair of formwork fastening hardware 3 and 4 having a cross-sectional shape are disposed facing each other along the direction.

Therefore, when forming a concrete product, the upper formwork 1 and the lower formwork 2 are tightened at the pair of frame fastening hardware 3 and 4, and centrifugal force is utilized by known rotary compaction forming. After the product is molded and cured, the mold fastening hardware 3 and 4 are released and the product is removed from the mold.

By the way, when tightening the formwork fastening hardware 3 and 4, for example, as shown in FIG. 5 is rotated upward, and in the rotational position of the eyebolt 5 as shown in FIG. It is common to attach a washer 8 and tighten it firmly with a nut 9.

Further, the end portion 1a of the upper formwork 1 is set back by a predetermined distance (approximately 5yo++) from the lower surface of the formwork fastening hardware 3,
In addition, the end 2a of the lower formwork 2 is made to protrude by a predetermined dimension from the upper surface of the formwork fastening hardware 4, so that it can be connected to the end 1a of the upper formwork 1 when tightening the upper and lower formworks 1 and 2. The ends 2a of the lower formwork 2 are engaged with each other to prevent mutual displacement of the formworks, and
It has a certain degree of sealing performance to prevent leakage of concrete slurry introduced into the formwork.

Further, a suitable packing material 10 is attached to the formwork fastening hardware 4, and when the upper and lower formwork fastening hardware 3, 4 are tightened, the packing material 10 is elastically deformed to some extent, thereby tightening the formwork. It is compressed to a thickness equal to the predetermined joint width 1 between the metal fittings 3 and 4, and the joint between the upper and lower formworks 1 and 2 is sealed.

Note that the joint width 1 is equal to the difference (1211) between the above-mentioned recession dimension 1 of the end 1a of the upper formwork 1 and protrusion dimension 12 of the end 2a of the lower formwork 2, and is regulated by this. Dimensions.

In the conventional formwork for centrifugal force forming having such a configuration, since the joint width 1 exists between the protruding pieces 3a and 4a of the upper and lower formwork fastening hardware 3 and 4, the fastening means such as the eyebolts 5 are not used too much. If it is tightened strongly, the cantilevered protruding pieces 3a and 4a will be bent and deformed, and sufficient tightening will not be achieved, resulting in insufficient sealing effect of the packing material 10 and the concrete slurry will rotate. There was a problem that it leaked during molding.

Furthermore, if the fastening metal parts of the formwork itself are deformed, the formwork itself becomes unfit for repeated use.

The present invention was devised to solve this problem, and its gist is that the upper formwork and the lower formwork, which constitute the formwork for centrifugal force forming, are arranged at opposite ends thereof. A spacer having a height equal to a predetermined joint width between the pair of formwork fastening hardware when the formwork is tightened is provided on either or both of the attached pair of formwork fastening hardware, and a spacer is provided to prevent leakage of concrete slurry. The problem lies in the fact that a preventive elastic packing material is attached.

Preferred embodiments of the present invention will be described below with reference to the drawings.

The same elements as the conventional example in FIGS. 1 and 2 are as follows.
Displayed with the same code.

FIGS. 3 and 4 show an embodiment of the present invention, and numerals 1 and 2 in the figures are an upper mold frame and a lower mold frame for centrifugal force forming, each having a semicircular cross section.

At both ends 1a and 2a of the upper formwork 1 and lower formwork 2,
A pair of formwork fastening hardware 3 and 4 made of angle members with a cross-section having a cross-section are mounted facing each other.

Predetermined notches 6 and 7 are formed in the pair of formwork fastening hardware 3 and 4 at appropriate intervals along the long side direction and at mutually corresponding positions.

Directly below the notch 7, a rotating shaft 12 is fixed between a pair of stiffeners 11, 11 protruding from the formwork fastening hardware 4, and an eye bolt 5 is rotatably attached to the rotating shaft 12. It is pivoted.

The end portion 1a of the upper formwork 1 is set back by a predetermined dimension from the lower surface of the upper formwork fastening hardware 3, in other words, the formwork fastening hardware 3 is projected by a dimension L□. Installation.

Further, the end portion 2a of the lower formwork 2 is connected to a fastening hardware 4 of the lower formwork.
It is attached so as to protrude from the upper surface by a predetermined distance L2, and when the upper and lower formworks 1 and 2 are tightly connected, the above-mentioned both ends 1a and 2a are engaged, and the upper and lower formwork fastening hardware 3 and 4
The joint width between each of the protruding pieces 3a and 4a is the difference (L2-Ll) between the retraction dimension of the upper formwork 1 and the protrusion dimension L2 of the lower formwork 2.

Near the tip of the protruding piece 4a of the lower formwork fastening hardware 4,
A spacer 13 having a height equal to the joint width is fixed.

As shown in FIG. 3, the spacer 13 is separated at the formation positions of the notches 6 and 7 of the upper and lower formwork fasteners 3 and 4, respectively, and is installed along the long side direction of the formworks 1 and 2. It is worn.

The spacer 13 is made of a material strong enough not to be deformed by compressive force when tightening the formwork, which will be described later.

In addition, near the base end of the protruding piece 4a of the lower formwork fastening hardware 4, an elastic material for preventing leakage of concrete slurry having a height L approximately equal to the protruding height L2 of the end 2a of the lower formwork 2 is provided. A packing material 14 is continuously attached along the long side direction of the lower formwork 2.

The packing material 14 has a cross-sectional shape in which the lower part of the outer end portion 14a projects slightly outward, and the protruding portion of the packing material 13 is held by a packing pressing material 15 having a height equal to or less than the height L of the spacer 13. 16 is pressed and held from above, and the protruding piece 4a is fixed to prevent removal.

Additionally, in FIG. 3, reference numeral 17 is a tire for rotating the upper and lower formworks 1 and 2.

Next, the effects of this embodiment will be explained.

First, the upper and lower formworks 1 and 2 are moved from the state shown in FIG. A large diameter washer 8 is fitted and a waist nut 9 is used to firmly tighten the upper and lower formworks 1 and 2.

At this time, the end 1a of the upper formwork 1 engages with the end 2a of the lower formwork 2 to eliminate misalignment between the forms, and the elastic packing material 14 is compressed to the height L of the spacer 13. The joints between the upper and lower formworks 1 and 2 are tightly sealed by deforming until they become equal.

Here, the packing material 14 is formed of a material that remains within its elastic limit even if it is compressed and deformed to the above-mentioned height L.

Even if the nut 9 is tightened strongly, since the spacer 13 is still provided, the projecting pieces 3a and 4a of the formwork fastening hardware 3 and 4
The upper and lower formworks 1 and 2 can be tightly connected without being deformed.

Furthermore, the elastic packing material 14 is a packing presser material 1.
5, there is no fear that the packing material 14 will come out even if the mold is used repeatedly.

Furthermore, if the height of the packing retainer 15 is made equal to the height of the spacer 13, the protruding pieces 3a and 4a will be supported on both sides of the eye bolt 5 when the nut 9 is tightened, thereby reducing the risk of deformation. It becomes less.

Note that in this embodiment, the spacer 13 and the elastic packing material 14 are
and the packing material 15 are both attached to the lower formwork fastening hardware 4.
Although an example is shown in which these are attached to the upper and lower formwork fastening hardware 3 or 4, it is sufficient that they are attached to either one of the upper and lower formwork fastening hardware 3 or 4.

However, the elastic packing material 14 and the packing pressing material 15 are naturally attached to the same hardware 3 or 4.

The spacer 13 and the elastic packing material 14 can also be provided separately for both the upper and lower formwork fastening hardware 3 and 4. In this case, each elastic packing material 14', 14' (
(not shown) may be held by packing pressers 15', 15' (not shown).

Further, the eye bolts 5 may be attached to the upper formwork 1 in the same configuration as described above, and furthermore, the end portion 1a of the upper formwork 1 is made to protrude by a predetermined amount, and the end portion of the lower formwork 1 is 2a
Even if it is set back by a predetermined distance L1, the same effects as in the above embodiment can be obtained.

Furthermore, the means for tightening the upper and lower formworks 1 and 2 is not limited to the case where the eye bolts 5 described above are used, but other suitable tightening means such as a so-called one-touch method can be used.

In the present invention configured as described above, when the upper and lower formworks are tightened, bending deformation of the formwork fastening hardware can be prevented and the formworks can be firmly connected to each other, and thereby the elasticity An even and wide surface pressure is applied to the contact surface with the packing material, and the elastic packing material can effectively prevent leakage of concrete slurry from the joints between the formworks.

[Brief explanation of drawings]

Fig. 1 is a schematic vertical cross-sectional view showing a conventional centrifugal force forming mold;
FIG. 2 is a longitudinal sectional side view of a main part showing the manner in which the formwork shown in FIG. 1 is fastened. Figures 3 and 4 show an embodiment of the centrifugal forming mold according to the present invention, with Figure 3 being a partially cutaway side view, and Figure 4 being a longitudinal cross-section of the main part showing how the upper and lower molds are tightened. It is a front view. 1... Upper formwork, 2... Lower formwork, 3...
... Upper formwork fastening hardware, 4... Lower formwork fastening hardware, 13... Spacer, 14... Elastic packing material, 15... Packing material. Pressing material.

Claims (1)

[Scope of utility model registration request] In the formwork for centrifugal force forming, the tip portions of a pair of upper formwork fastening hardware 6 and the tip portions of the lower formwork fastening hardware 7 are fixed to opposite ends of each of the upper formwork 1 and the lower formwork 2. and a concrete slurry having a height equal to a predetermined joint width between the pair of formwork fastening hardware when the formwork is fastened, and further having a thickness higher than the spacer 13 by a predetermined dimension. A formwork for concrete products formed by centrifugal force forming, characterized in that a leakage-preventing elastic packing material 14 is attached to prevent removal by a packing holding material 15 having a height equal to or lower than that of the spacer 13.