JP6385189B2 - Method and apparatus for producing concrete products - Google Patents

Description

  The present invention relates to a method for manufacturing a concrete product and a manufacturing apparatus. More specifically, the present invention relates to a manufacturing method and a manufacturing apparatus for a concrete product including a reinforcing steel bar.

In order to increase the strength of precast concrete products, reinforcing bars are disposed inside, and there is a manufacturing method of Patent Document 1 as such a conventional technique.
In the manufacturing method of Patent Document 1, a reinforcing material is disposed in a mold 1 and a concrete material is supplied.

An example of the manufacturing method which arrange | positions a reinforcing bar in the above molds is demonstrated based on FIGS. 5-7 and FIG.
In FIG. 5, reference numeral 100 denotes a mold, which includes a bottom plate 101 and a side plate 102 standing on its periphery. The upper surface is opened. The opening of the formwork 100 is installed facing upward, and the rebar 110 is passed over the side plate 102. At this time, the reinforcing bar 110 is placed horizontally. 105 is an intermediate | middle board, and in order to hold | maintain the extra part of concrete material, it mounts on the mold 100. FIG. This state corresponds to I in FIG.

  Next, as shown in FIG. 6, the concrete material m is supplied. The concrete material m fills the mold 100 and is piled up to the upper end of the intermediate plate 105. In this state, the pressing material 106 is used to vibrate and press the concrete material m. At this time, the reinforcing bar 110 is curved so that the central portion is recessed. This state corresponds to II in FIG.

Next, the mold 100 is turned upside down, and the concrete semi-finished product Z is allowed to stand on the upper surface of the mounting plate 120 as shown in FIG. Then, the mold 100 is pulled upward and removed. This state corresponds to III in FIG.
In this stationary state, the concrete material m shifts from a water-containing state to a dry state. At the same time, the curved reinforcing bar 110 tries to return to the original straight state, and both end portions thereof are lifted upward (indicated by arrows f). Based on the behavior of the reinforcing bar 110, deformation v such as swell, cracks, and cracks occurs on both end surfaces of the semi-finished concrete product Z.

  As can be seen from the curved state of the reinforcing bar 110 shown in II to IV in FIG. 8, the above-described problem is that a force f, that is, a springback is generated in the reinforcing bar 110 that has been deformed once. Therefore, the deformation v of the concrete product inevitably occurred.

JP 2001-47422 A

  In view of the above circumstances, an object of the present invention is to provide a method and an apparatus for manufacturing a concrete product that does not cause deformation such as swell, cracks, and cracks on the surface of the concrete product.

A method for producing a concrete product according to a first aspect of the present invention is a method for producing a concrete product with reinforcing bars using a mold having a bottom plate and a side plate and having an opening on the upper surface, wherein the opening is installed upward. A setting process for passing the reinforcing bar on the side plate in the mold, a reinforcing bar bending process for pressing the both ends of the passed reinforcing bar downward and bending the central part upward, and supplying concrete material into the mold It is characterized by performing a material pressurizing step for deforming the steel bar so as to approach the rebar straightly, and a demolding step for removing the mold after inverting the mold.
According to a second aspect of the present invention, there is provided a method for producing a concrete product according to the first aspect, wherein the reinforcing bar bending step uses the presser member attached to the back surface of the intermediate plate that holds the surplus portion of the feeding material in the feeding step. It is characterized in that it is carried out by pressing down both end portions of the.
The concrete product manufacturing apparatus of the third invention is a concrete product manufacturing apparatus used in the manufacturing method of the first invention, and the manufacturing apparatus includes a mold having a bottom plate and a side plate and having an opening on the upper surface. The side plate of the formwork is formed with holding grooves that hold both ends of the passed reinforcing bars downward and hold the central part curved upwards. method for producing a product, in the first or second invention, before Symbol rebar, characterized in that both end portions are formed in the high-rigidity area with improved rigidity than the central portion.

According to the first invention, since the central portion of the reinforcing bar passed to the formwork in the reinforcing bar bending step is curved upward, even if the pressing pressure acts on the concrete material m in the next feeding step, The rebar only deforms to approach straight. For this reason, since the spring back of the reinforcing bar does not occur in the concrete product after the demolding process, the concrete product is not deformed such as distortion or swell phenomenon.
According to the second invention, when the intermediate plate used in the feed material pressurizing step is lowered, both ends of the reinforcing bar are simultaneously pressed downward at that time, so that the central part of the reinforcing bar is bent upward by the reaction. For this reason, since a reinforcing bar bending process is automatically performed before a feed material pressurizing process, operational efficiency improves.
According to the third aspect of the invention, since the reinforcing bar passed over the mold is held by the holding groove provided on the side plate and becomes a fulcrum when bending, the reinforcing bar can be bent reliably.
According to the fourth aspect of the invention, since both ends of the reinforcing bar have increased rigidity, it is easy to bend the central portion having lower rigidity than both ends. For this reason, rebar bending work can be performed reliably.

It is explanatory drawing of all process I-IV in the concrete product manufacturing method which concerns on this invention. It is explanatory drawing of the reinforcing bar bending process which concerns on this invention. It is explanatory drawing in the feed material pressurization process which concerns on this invention. It is explanatory drawing of the demolding process which concerns on this invention. It is explanatory drawing of the setting process in the conventional manufacturing method. It is explanatory drawing of the material pressurization process in the conventional manufacturing method. It is explanatory drawing of the concrete semi-finished product Z after the demolding process in the conventional manufacturing method. It is explanatory drawing of all process I-IV in the conventional manufacturing method.

Next, an embodiment of the present invention will be described with reference to the drawings.
The concrete product to which the manufacturing method and the manufacturing apparatus of the present invention are applied is a concrete product having a block shape and having reinforcing reinforcing bars inside.

First, a manufacturing apparatus is demonstrated based on FIG.
The manufacturing apparatus of the present invention includes a mold 1 and an intermediate plate 6.
The mold 1 is a box-shaped member having a bottom plate 2 and side plates 3 and having an opening on the upper surface. In addition, the side plate 3 of the mold 1 is formed with a holding groove 4 that holds a reinforcing bar to be passed.
The intermediate plate 6 is a member having a side frame 7 having four sides and having an open central portion. This opening forms a space where the concrete material m is piled up. Further, presser members 8 are attached to the lower surfaces of both end portions of the intermediate plate 6. The pressing member 8 is a member for pressing down both end portions of a reinforcing bar 10 to be described later.

The reinforcing bar 10 is not particularly different from a reinforcing bar used for normal reinforcement, but a high-rigidity part 11 having higher rigidity than the central part is formed at both ends thereof.
In order to form the high-rigidity portion 11, it is preferable to bend the reinforcing bars and weld them together. However, the short reinforcing bars are not bent and the short reinforcing bars are fixed with a wire without welding. Any means such as a thing can be taken.

Next, the production method of the present invention will be described with reference to FIG. 1 and FIGS.
(Set process)
As shown in FIG. 2, the mold 1 is installed with the opening facing upward. A reinforcing bar 10 is passed between the opposing side walls 3 and 3 of the mold 1. The crossing of the reinforcing bars 10 may be performed in the oblique direction in the quadrangular formwork 1 or in the vertical and horizontal directions.
Further, the reinforcing bars 10 are passed so as to drop into the holding grooves 4 formed on the side plates 3. The high-rigidity portion 11 of the reinforcing bar 10 is provided on both the outside and the inside of the side wall 3 with the holding groove 4 as a boundary. In FIG. 1, the state is indicated by I.

(Rebar bending process)
As shown in FIG. 2, the intermediate plate 6 is placed on the mold 1, and the high rigidity portions 11 at both ends of the reinforcing bar 10 are pushed down by the pressing member 8 of the intermediate plate 6. Then, since the bottom of the holding groove 4 becomes a fulcrum, the outer end of the high-rigidity portion 11 of the reinforcing bar 10 is inclined so as to face downward, and the central portion of the reinforcing bar 10 is curved so as to protrude upward by the reaction. . The curved state of the reinforcing bars 10 is held while being pushed down by the intermediate plate 6.

(Feeding process)
Next, as shown in FIG. 3, a concrete material m is fed. At this time, the extra space of the concrete material m is held in the space in the intermediate plate 6. As described above, when the concrete material m is supplied into the mold 1, vibration is applied and pressure is applied using the pressure plate 9.
When the concrete material m is vibrated and pressed by the pressing plate 9, the rebar 10 is also pushed downward, so that the degree of bending is reduced and the state approaches a horizontal state.

(Demolding process)
Next, as shown in FIG. 4, after reversing the mold 1, the concrete product A is placed on the placing plate 20, and the mold 1 is pulled upward. In this state, the concrete material m is dried from the water-containing state and becomes a concrete product A. And the concrete material m of the enclosure hardens | cures in the state in which the internal reinforcement 10 maintained substantially horizontal.

Next, the features of this production method will be described.
Since the central portion of the reinforcing bar 10 passed to the mold 1 in the reinforcing bar bending process shown in I of FIG. 1 is curved upward, a pressing pressure acts on the concrete material m in the next feeding material pressing process II. However, the rebar 10 only deforms so as to approach straight. For this reason, since the spring back of the reinforcing bar 10 does not occur in the concrete product A after the demolding process III, deformation v such as distortion, swelling, cracks, cracks, etc. does not occur in the concrete product A.

1 Formwork 3 Side plate 4 Holding groove 10 Reinforcement m Concrete material A Concrete product

Claims (4)

A method of manufacturing a concrete product with reinforcing bars using a mold having a bottom plate and a side plate and having an opening on the top surface,
A setting step of passing a reinforcing bar over a side plate in the mold frame with the opening facing upward;
Reinforcing bar bending process in which both ends of the passed reinforcing bar are pressed downward and the central part is bent upward,
Feeding and pressing the concrete material into the mold and pressurizing and deforming the reinforcing bar so as to approach straight; and
A method of producing a concrete product, comprising: performing a demolding step of removing the mold after the mold is inverted. The reinforcing bar bending step is performed by pressing both ends of the reinforcing bar downward using a pressing member attached to the back surface of the intermediate plate that holds the extra supply portion in the supplying step. The method for producing a concrete product according to claim 1. It is a concrete product manufacturing apparatus used with the manufacturing method of Claim 1, Comprising: This manufacturing apparatus is provided with the formwork which has a baseplate and a side plate, and has an opening in an upper surface, and is passed over the side plate of the said formwork. An apparatus for manufacturing a concrete product, characterized in that a holding groove is formed to hold both ends of the reinforcing steel bar downward and hold the central part curved upward . Before SL rebar claim 1 or 2 method for producing a concrete product according characterized in that both end portions are formed in the high-rigidity area with improved rigidity than the central portion.

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