JP2726399B2 - Method and apparatus for molding concrete product - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete product having a hollow portion such as a through hole or a hole that does not penetrate with a depth greater than the hole diameter, and a method and apparatus for molding the concrete product. And a product for molding this concrete product.

[0002]

2. Description of the Related Art Recently, with the burial of so-called trunk lines such as communication lines, power lines, gas pipes, water pipes, and sewer pipes,
For wiring to communication lines and power lines to users, concrete products such as electric wire common grooves installed underground such as passageways are mainly used.

Conventionally, as this kind of concrete product, for example, a centrifugal reinforced concrete pipe (JIS-A
5303) A method of molding a concrete pipe having a through hole using centrifugal force without using an inner frame forming the inner wall surface of the through hole as in 5303), a concrete having a through hole by forming a draft in the inner frame A method of molding a pipe, a method of disassembling an inner frame into two or more to form a concrete pipe having a through hole, and a method of removing a middle frame main body during demolding as described in Japanese Utility Model Publication No. 1-12626. It is known to mold a concrete block having a through hole by using a medium-sized die having a reduced diameter.

[0004]

In the molding method utilizing the centrifugal force, the diameter of the through-hole of the reinforced concrete pipe tends to be relatively large with respect to its length.
Only one through hole can be molded at the center from the mechanism, and the device for molding the concrete pipe is a large-scale device equipped with a rotating mechanism and the configuration becomes complicated. is there. Also, in the molding method using the inner frame having a draft angle, a gradient is also formed in the through hole itself, and when forming a through hole having a depth greater than the hole diameter, the through hole is formed by the draft angle. There is a problem that a large difference occurs in the hole diameter between the entrance and the exit.

In the molding method of disassembling the inner frame into two or more parts, it takes time and effort to assemble or disassemble the inner frame. There is a problem that an excessive force is applied and the inner frame is easily damaged.

Further, in the configuration disclosed in Japanese Utility Model Publication No. 1-12626 in which the diameter of the middle frame body is reduced, the configuration in which the diameter of the middle frame body is reduced is complicated, and the cost disadvantage is large.
In addition, the concrete trocars are easily attached to the matching portion due to the configuration, and the insertion member for matching the opening into the opening of the middle frame body is drawn into the middle frame body, so that it takes time to remove the concrete trochus. There is.

Further, since the inner wall of each through-hole formed by each of the above-mentioned forming methods is formed into a smooth surface having no irregularities, for example, a cable is drawn into each through-hole and installed. In this case, since the contact area between the through hole and the cable is large, frictional resistance is large, an excessive tension is required for drawing in the cable, and there is a problem that the cable drawing operation is not easy.

In each of the molding means, the through-hole is formed in a straight line, and the through-hole is formed in a concrete product into a curved shape bent into, for example, a substantially L-shape. Is very difficult.

The present invention has been made in view of such a point, and when a penetrating member such as a cable is inserted into a hollow portion, the contact area with the inner wall surface of the hollow portion is small, so that the frictional resistance is small, and An object of the present invention is to provide a concrete product that does not require a drawing tension, is easy to perform a drawing operation, and is excellent in workability.

Further, according to the present invention, it is possible to easily mold a hollow portion having no difference in the hole diameter at the entrance and the exit, to easily release the molded hole, and to easily remove the trocars from the concrete. Accordingly, it is an object of the present invention to provide a concrete product molding method in which a concrete product having a hollow portion can be easily molded.

Further, the present invention is preferable for an embodiment of a concrete product molding method, and provides a concrete product molding apparatus which has a simple structure, is easy to assemble and release, and has a high cost merit. It is the purpose.

Further, the present invention can easily mold a concrete product having a curved hollow portion bent into a substantially L-shape or the like, for example, and can easily perform a releasing operation of the concrete product molding apparatus. The purpose is to provide.

[0013]

According to a first aspect of the present invention , there is provided a method for forming a concrete product , the method comprising :
Core that forms a hollow portion that is open at least on one end surface
When the outer periphery of the material expands, the outer peripheral surface is sectioned along the axial direction
A flexible hollow core that forms a concave and convex surface
Holding the core material having the hollow core body fitted therein,
The hollow core is expanded in the hollow
Concrete is poured around the child and cured.
The hollow core is formed by molding the product and sucking the pressure fluid.
The hollow core body and the core
The core material is pulled out of the concrete product and released . Then, the inner wall surface is concave along the axial direction
Easy to use concrete products with convex hollows
Molded, this is in the hollow portion is easily inserted is drawn smoothly without requiring excessive pull tension insertion member such as a cable.

The method for molding a concrete product according to the second aspect is the same as the method for molding a concrete product according to the first aspect.
The hollow core body has an expandable and contractable chip with one end sealed.
A hollow core made of this tube
Is spirally wound around the outer peripheral portion of the core material . The helically wound hollow core is expanded with a pressure fluid.
Pile concrete around the hollow core in the expanded state.
By setting and curing, the spiral shape along the axial direction
A concrete product having a hollow portion in which the inner wall surface is formed in an arc-shaped uneven surface along the axial direction on the uneven outer peripheral surface is easily molded.

According to a third aspect of the present invention, in the method for molding a concrete product according to the second aspect , the outer peripheral portion of the spirally wound hollow core is formed.
It is covered with a flexible sheet . And flexible
The sheet has a winding pitch of a hollow core that is spirally wound.
The part located in between is the core
Concrete is bent in an arc-shaped section toward the core material.
Cured. Therefore, the hollow core is spirally wound.
A concrete product having a hollow portion in which the inner wall surface is formed in an arc-shaped uneven surface along the axial direction in accordance with the winding pitch thus formed is easily formed.

A molding device for a concrete product according to claim 4.
The mold is provided with a mold, a hole-formed body and a fluid provided in the mold.
Supply and discharge means, wherein the hole-formed body is made of concrete.
Form a hollow part that is open on at least one end surface of the product
Core material which is fitted to the core material
Part is formed on an arc-shaped uneven surface along the axial direction
And the fluid supply / discharge means is provided with the hole
Supplying pressurized fluid into the flexible hollow core of the molded body
At the same time, the pressure fluid is sucked.

And a hollow shape expanded by the supply of a pressure fluid.
When the core is expanded, the outer periphery of the hollow core extends in the axial direction.
It is formed and held on an arc-shaped uneven surface along the cross section. Also,
The hollow core is contracted flat by suction of the pressure fluid.
This allows the hollow core to be molded into a concrete product.
Release from the surface. Therefore , a concrete product having a hollow portion in which the inner wall surface is formed in an arc-shaped uneven surface along the axial direction is easily molded.

The concrete product molding apparatus according to the fifth aspect is the same as the concrete product molding apparatus according to the fourth aspect.
The hollow core of the hole-formed body is
Formed by an inflatable tube spirally wound along
It is a thing. And a hollow core wound spirally
A concrete product having a hollow portion in which the inner wall surface is formed into an arc-shaped uneven surface along the axial direction by the spiral uneven outer peripheral surface is easily molded.

The concrete product molding apparatus according to a sixth aspect of the present invention is the concrete product molding apparatus according to the fifth aspect , wherein the outer peripheral portion of the spirally wound hollow core is covered.
Flexible sheet . And predetermined
Outer periphery of a hollow core body spirally wound at a winding pitch of
Is covered with a flexible sheet,
The pitch is between the winding pitches of the spirally wound hollow core.
The part located at the core
The concrete grows in a state where it is bent in an arc cross section toward the material.
Be born.

The concrete product molding apparatus according to claim 7 is the concrete product molding apparatus according to any one of claims 4 to 6, wherein the core material is bendable.
It is made of a flexible body . And inside the flexible body
Bending the core material into a predetermined shape and disposing it on the mold
The inner wall surface is formed into an arc-shaped uneven surface along the axial direction
Conc having a curved straight hollow portion and a curved hollow portion
A reed product is molded.

[0021]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In the embodiment shown in FIGS. 1 to 3,
Reference numeral 1 denotes a mold, and the mold 1 has a bottom plate (not shown) provided integrally with a gantry, and left and right side plates 2 provided on left and right portions of the gantry so as to be able to advance and retreat toward the bottom plate. Are arranged vertically. The left and right side plates 2 are formed in a predetermined height and long in the front-rear direction.

In addition, front and rear end plates 3 which are provided so as to be able to advance and retreat toward the bottom plate are vertically arranged at the front and rear portions of the mount, respectively. The front and rear end plates 3 are sandwiched between the front end portions and the rear end portions of the left and right side plates 2 and are formed in a rectangular shape at the same height as the left and right side plates 2. A cylindrical support 5 having an insertion hole 4 having a diameter substantially the same as a through hole as a hollow portion formed in a concrete product body, which will be described later, is provided at the center of the front and rear end plates 3 to face outward. It protrudes integrally toward.

Next, reference numeral 6 denotes a hole-formed body disposed on the mold 1. The hole-formed body 6 is composed of a core 7 and a flexible member fitted to the core 7. And a hollow core body 8. The core 7 forms a through hole as a hollow portion having both ends opened in the concrete product, and has a length to be inserted into the insertion holes 4 of the front and rear end plates 3. The cross-sectional shape has a diameter slightly smaller than the cross-sectional shape of the through hole. That is, when the diameter of the through-hole is circular, the diameter of the core 7 is formed in a circular cross-sectional shape that is slightly smaller than the circular hole diameter. The core 7 is made of steel, synthetic resin, wood, rubber, or the like, or a combination thereof.

The hollow core 8 has a deformable tubular portion 9 formed of a flexible material in a hollow tubular shape, and one end of the tubular portion 9 is connected to the middle portion. It is opened as an insertion opening 10 for inserting the core material 7, and is integrally formed at the other end of the cylindrical portion 9 as an opposing side plate 12 facing the insertion end 11 of the core material 7. I have.

The outer peripheral portion of the cylindrical portion 9 is formed with an arc-shaped uneven surface 13 along the axial direction. That is,
In a state where the cylindrical portion 9 is fitted to the core 7, the arc-shaped concave-convex surface 13 is formed from the arc-shaped concave portion 14 and the core 7, which are concave toward the core 7. It has an arc-shaped convex portion 15 protruding in an arc-shaped cross section toward the separating direction, and is formed in a spiral shape along the axial direction.

The arc-shaped concave portion of the arc-shaped concave-convex surface 13
The arc-shaped convex portion 14 and the arc-shaped convex portion 15 are expanded by the pressure fluid supplied into the cylindrical portion 9 and held in the shape of the arc-shaped concave portion 14 and the arc-shaped convex portion 15, and the pressure fluid is sucked from the inside of the cylindrical portion 9. As a result, the arc-shaped concave portions 14 and the arc-shaped convex portions 15 are contracted and deformed into a shape along the core material 7.

A tube 16 communicating with the inside of the tubular portion 9 is integrally formed at one end of the tubular portion 9.
Then, the cylindrical portion 9 of the hollow core 8 is fitted to the core 7, and one end of the cylindrical portion 9 is annularly attached to the outer periphery of one end of the core 7. At 17 it is kept closed. A fluid container 18 for pressurized fluid is formed in the hollow core body 8 around the core 7.

Next, reference numeral 19 denotes a fluid supply / discharge means for supplying and discharging a pressurized fluid into and from the fluid accommodating portion 18 of the hollow core 8, and the fluid supply / discharge means 19 has a conduit 20; Conduit 20
A connecting pipe 21 connecting and connecting the connecting end of the tube 16 is protrudingly provided at an intermediate portion of the tube 16, and one end of the conduit 20 is provided with a fluid housing of the hollow core body 8 through the tube 16. Part 18
A fluid supply device 22 for supplying a pressure fluid to the inside is connected.

The fluid supply device 22 supplies a gas such as air to the fluid container 18 of the hollow core 8 through the tube 16.
It is composed of a compressor for supplying pressure into the inside, a cylinder filled with fluid gas, and a pump mechanism for supplying a liquid such as water or oil to the fluid accommodating portion 18 of the hollow core 8 through the tube 16. .

A valve body 23 for opening and closing the inside of the conduit 20 is interposed in the middle of the conduit 20 to which the fluid supply device 22 is connected, that is, in the middle of one side centered on the connection pipe 21. The supply and stop of the pressure fluid from the fluid supply device 22 are controlled by the valve body 23.

The other end of the conduit 20 is connected to a fluid discharge device 24 for sucking and discharging the pressure fluid in the fluid storage portion 18 of the hollow core 8 through the tube 16. I have. The fluid discharge device 24 is a vacuum device that sucks and discharges gas or liquid in the fluid storage portion 18 of the hollow core 8 through the tube 16.

Further, a valve body 25 for opening and closing the inside of the conduit 20 is interposed in the middle of the conduit 20 to which the fluid discharge device 24 is connected, that is, in the middle of the other side centering on the connection pipe 21. The valve body 25 controls the suction and stop of the pressure fluid of the fluid discharge device 24.

Next, the operation of the above embodiment will be described.

The front and rear end plates 3 are respectively disposed on the front and rear portions of the bottom plate, and the left and right side plates 2 are disposed on the left and right portions of the bottom plate, respectively, and the front end plate is disposed between the front ends of the left and right side plates 2. 3 and hold the rear side plate 2 between the rear ends of the left and right side plates 2 to form a mold. The left and right side plates 2 and the front and rear side plates 3 are attached and detached by fixing means (not shown). Adhere if possible. The bottom frame, the left and right side plates 2 and the front and rear end plates 3 constitute a mold 1 having an open upper surface.

Next, the core 7 to which the hollow core 8 is fitted is inserted from the insertion hole 4 of the one end plate 3 of the mold 1 to the other end plate 3 with the opposite side plate 12 as an insertion end. By being inserted through the insertion hole 4, both ends of the core 7 to which the hollow core 8 is fitted are supported by the insertion holes 4 of the front and rear end plates 3.

At this time, the cylindrical portion 9 of the hollow core 8 has flexibility, and the fluid containing portion 18 in the cylindrical portion 9 is not supplied with the pressurized fluid. The core core material 7 with the core body 8 fitted therein is easily inserted from the insertion hole 4 of the one end plate 3 to the insertion hole 4 of the other end plate 3.

Next, while closing the valve body 25 provided on the conduit 20 on the fluid discharge device 24 side to close the conduit 20, the valve body 23 provided on the conduit 20 on the fluid supply device 22 side is opened. To open the conduit 20. When the fluid supply device 22 is operated, the fluid supply device 22 causes the conduit 20 and the tube 16
Then, a pressurized fluid such as pressurized air is supplied into the fluid accommodating portion 18 of the hollow core body 8 through the above, the tubular portion 9 is expanded by the pressurized fluid, and the tubular portion 9 is held in a rigid shape. .

The outer peripheral surface of the cylindrical portion 9 has an arcuate concave / convex surface formed of an arcuate concave portion 14 and an arcuate convex portion 15 along the axial direction.
13, the shape of the arcuate uneven surface 13 is held hard, and the cylindrical portion 9 is held in a state that can sufficiently withstand the concrete driving pressure. Also, the cylindrical portion 9
When is expanded and held in a hard shape, both ends of the tubular portion 9 are brought into contact with the insertion holes 4 of the front and rear end plates 3 in a liquid-tight manner.

In the mold 1, a required number of reinforcing bars are arranged and fixed at predetermined intervals in the left-right direction and the front-back direction. If necessary, the hollow core body is held by a holding member protruding from a reinforcing bar provided around a hollow core body 8 supported by the insertion holes 4 of the end plate 3 in front and behind the form 1. Position 8

Accordingly, as shown in FIG. 2, the core 7 on which the hollow core 8 is fitted is held in the mold 1 and both ends of the hollow core 8 of the core 7 are formed. The part is liquid-tightly matched in the insertion holes 4 of the front and rear end plates 3.

Next, the hollow core body 8 in the mold 1 is held in a state where the cylindrical portion 9 of the hollow core body 8 provided and supported between the front and rear end plates 3 is expanded and held by the pressure fluid. Concrete is sufficiently poured around the cylindrical portion 9 of the concrete product 8 and the concrete is cured for a required time until the concrete solidifies.
Then, a through-hole B having both ends open as a hollow portion penetrating the concrete product body A is formed. Since the cylindrical portion 9 of the hollow core 8 is continuously sufficiently expanded and held by the pressure fluid during the concrete placement and curing, a cross section of the outer peripheral surface of the cylindrical portion 9 of the hollow core 8 is maintained. Arc-shaped uneven surface
At 13 concrete is formed.

Next, when removing the concrete product main body A, the valve body provided in the conduit 20 on the fluid supply device 22 side is used.
23 is closed to close the conduit 20, while the fluid discharge device 24 is closed.
The conduit 20 is opened by opening the valve body 25 provided on the side conduit 20. And when this fluid discharge device 24 is operated,
The fluid discharge device 24 sucks and discharges a pressure fluid such as air in the cylindrical portion 9 of the hollow core 8 fitted to the core 7 and discharges the hollow core 8. As shown in FIG. 3, the cylindrical portion 9 is contracted and bent along the core 7 to be deformed to be small.

Then, as shown in FIG.
Pull-out gaps 26 are formed between the cylindrical portion 9 and the through hole B formed in the concrete product main body A, and between the both end portions of the cylindrical portion 9 and the insertion holes 4 of the front and rear end plates 3 respectively. It is formed. Then, the core 7 with the tubular portion 9 of the hollow core 8 fitted therein is pulled out, and the through hole B formed in the concrete product main body A and the insertion holes 4 of the front and rear end plates 3 are formed.
Release from

Further, the left and right side plates 2 of the mold 1 are retracted from the concrete product main body A to release the mold, and the front and rear end plates 3 are respectively retracted from the concrete product main body A to release the mold. 1 is demoulded. Further, by lifting the concrete product body A with a crane or the like and taking out the concrete product body A from the bottom plate of the gantry, the concrete product body A in which the through hole B is formed as shown in FIG. 4 is obtained.

Thus, the concrete product body A
As shown in FIGS. 4 and 5, the inner wall surface C of the through hole B formed in the concrete product body A has an arc-shaped unevenness in the outer peripheral surface of the cylindrical portion 9 of the hollow core body 8. The surface 13 is formed into an arc-shaped uneven surface D having a smooth cross section along the axial direction. That is, since the cross-section arc-shaped uneven surface 13 of the outer peripheral surface of the cylindrical portion 9 is formed of a spiral arc-shaped concave portion 14 and an arc-shaped convex portion 15 along the axial direction, the through-hole B is formed by the arc-shaped concave portion 14 and the arc-shaped convex portion 15. The cross-section arc-shaped uneven surface D formed on the inner wall surface C is smoothly formed into a substantially wave-shaped cross-section at the arc-shaped concave portion d1 and the arc-shaped convex portion d2.

Next, when the concrete product body A is used as a buried groove for installing a cable, when the cable is drawn into the through hole B, a smooth surface D composed of the cable and the arcuate uneven surface D of the through hole B is required. The contact area with the substantially wavy inner wall C is small, the frictional resistance is small,
Excessive tension is not applied to the cable, so that the cable is easily pulled into and installed in the through hole B of the concrete product body A.

Next, in the embodiment shown in FIGS. 6 to 8, the hole-formed body 6 is made up of a core 27 and a core 7.
A hollow core body 29 formed of an expandable and contractible tube 28 spirally wound along an outer peripheral portion of the hollow core body 29, and an outer peripheral portion of the spirally wound hollow core body 29 is covered. This is provided with a tubular flexible sheet 30. Since other embodiments are the same as those in the above-described embodiment, the common portions are denoted by the same reference numerals used in the description of the above-described embodiment, and description thereof is omitted.

The core 27 is the same as that of the embodiment. Further, a tube 28 forming the hollow core body 29 is formed in a hollow cylindrical shape with elastic vinyl or rubber or the like, and one end portion spirally wound around the core core material 27 is airtight. Sealed in state. And this tube
Numeral 28 is expanded in a tubular shape by the supply of the pressure fluid, and spirally protrudes to the outer peripheral portion of the core core material 27. 27
Is formed along the spiral shape on the outer peripheral portion.

The flexible sheet 30 for covering the outer peripheral portion of the core material 27 in which the tube 28 is spirally wound is formed into a flexible hollow cylindrical shape by a sheet body of a synthetic resin or the like. The hollow cylindrical flexible sheet 30 is formed so that
Is formed so as to have an outer shape inserted into the insertion hole 4. The hollow cylindrical flexible sheet 30 is used to form a through hole B as a hollow portion in the concrete product main body A.

Next, the operation of the above embodiment will be described.

An expandable / contractible tube 28 whose one end is closed is spirally wound along the outer peripheral portion of the core 27. At this time, if the through hole B as a hollow portion molded into the concrete product main body A is a buried groove penetrating a cable or the like, the tube 28 is spaced from the outer peripheral portion of the core 27 by a predetermined distance. And spirally wound at a winding pitch.

In the case where the through hole B as a hollow portion formed in the concrete product main body A is a buried groove penetrating a water pipe or a sewer pipe, the outer peripheral portion of the core 27 is The tube 28 is spirally wound at a winding pitch smaller than the winding pitch of the buried groove for the cable or the like. At this time, the tube 28
It is preferable to form a spiral groove at a winding pitch at which is wound.
Further, the tube 28 may be attached to the contact surface with the outer peripheral portion of the core material 27 with an adhesive or the like as necessary, or may be fixed in position using an adhesive tape or the like.

Next, the valve body 23 provided on the conduit 20 on the fluid supply device 22 side is closed to close the conduit 20 while the valve body 25 provided on the conduit 20 on the fluid discharge device 24 side is opened. To open the conduit 20. When the fluid discharge device 24 is operated, a pressure fluid such as air in a tube 28 spirally wound around the core 27 is sucked and discharged by the fluid discharge device 24. 28 is contracted and crushed along the outer peripheral portion of the core 27, and is deformed to be flat and small.

The outer peripheral portion of the core material 27 in which the tube 28 is spirally wound is covered with a tubular flexible sheet 30 for forming a through hole as a hollow portion. At this time, as shown in FIG. 7, a tube 28 spirally wound around the outer peripheral portion of the core material 27 is used.
Is deformed to be flat and small, so that between the outer peripheral portion of the spirally wound tube 28 and the inner peripheral portion of the tubular flexible sheet 30, the tube 28 When the tube 28 is inflated, a gap 31 is formed so that the outer peripheral portion of the tube 28 is pressed against the inner peripheral portion of the flexible sheet 30.

Then, the core 28 obtained by spirally winding the tube 28 covered with the flexible sheet 30 is inserted through the insertion hole 4 of the one end plate 3 of the mold 1 into the other end plate 3. By being inserted into the hole 4, the hole molded body 6 is supported by the insertion holes 4 of the front and rear end plates 3. At this time, the tubular flexible sheet 30
Are inserted and supported in advance in the insertion holes 4 of the front and rear end plates 3, and the tube 28 is inserted into the tubular flexible sheet 30.
May be inserted into the core material 27 that is deformed into a flat shape. Then, the outer peripheral portion of the hole molded body 6 may be covered with a tubular flexible sheet 30.

Next, the valve body 25 provided on the conduit 20 of the fluid discharge device 24 is closed to close the conduit 20 while the valve body 23 provided on the conduit 20 of the fluid supply device 22 is opened. To open the conduit 20. When the fluid supply device 22 is operated, a pressurized fluid such as pressurized air is supplied from the fluid supply device 22 into the conduit 20 and the spiral tube 28, and the fluid is deformed flat and small by the pressure fluid. Tube 28
Is expanded and restored to a hard round bar shape.

When the spiral tube 28 is expanded and restored to a round bar shape, the outer peripheral portion of the spiral tube 28 is pressed against the inner peripheral portion of the tubular flexible sheet 30 as shown in FIG. The inner peripheral portion of the flexible sheet 30 is positioned and supported by the outer peripheral portion of the tube 28, and both ends of the flexible sheet 30 abut liquid-tightly in the insertion holes 4 of the front and rear end plates 3. Is done.

At this time, since the spiral tube 28 is sufficiently hard and expanded into a round bar shape by the pressurized fluid, the flexible sheet 30 is supported by the spiral tube 28 so that the flexibility is increased. The sheet 30 is supported in a state that can sufficiently withstand the concrete driving pressure. Then, between the inner peripheral portion of the flexible sheet 30 and the core core material 27, a release cavity 32 for pulling out the core material 27 around which the tube 28 is wound at the time of demolding is secured.

Therefore, the core 27, the core 27
A tube 28 spirally wound around and expanded into a hard round bar
And the tubular flexible sheet 30 are integrally combined to form the hole-formed body 6, and both ends of the flexible sheet 30 of the hole-formed body 6 Insertion hole 4
Liquid-tightly matched inside.

Next, the required number of reinforcing bars are arranged and fixed in the form 1 at predetermined intervals in the left-right direction and the front-rear direction similarly to the case of the above-described embodiment. Sheet of hole-formed body 6 supported by insertion hole 4 of end plate 3
The flexible sheet 30 is positioned by a reinforcing bar disposed around the periphery of the flexible sheet 30.

Next, as shown in FIG. 8, concrete is wrapped around the flexible sheet 30 in the mold 1 in a state where the spirally wound tube 28 is inflated and held in a hard round bar shape by a pressure fluid. The concrete product body A and a through-hole B having both ends open as hollow portions penetrating the concrete product body A are formed by sufficiently casting and curing for a required time until the concrete solidifies.

At this time, when the concrete is poured and cured, the spiral tube 28 continues to be expanded to a sufficiently hard and round bar shape by the pressure fluid.
Since the flexible sheet 30 is supported by the helical tube, the helical support portion 30a of the flexible sheet 30 supported on the outer periphery of the spiral pitch of the helical tube 28 is driven by a concrete placing pressure. However, the non-supporting portion of the flexible sheet 30 located between the winding pitches of the spiral tube 28 is slightly elastically deformed toward the core 27 by the driving pressure of the concrete. Then, it is deformed into a spiral arcuate surface 30b which swells smoothly.

Accordingly, the inner wall surface C of the through hole B formed in the concrete product main body A is formed into an arc-shaped uneven surface D by the spiral support portion 30a of the flexible sheet 30 and the spiral arc surface 30b. You.

Next, when removing the concrete product main body A, the valve body provided in the conduit 20 on the fluid supply device 22 side is used.
23 is closed to close the conduit 20, while the fluid discharge device 24 is closed.
The conduit 20 is opened by opening the valve body 25 provided on the side conduit 20. And when this fluid discharge device 24 is operated,
A pressure fluid such as air in the tube 28 wound around the core 27 is sucked and discharged by the fluid discharge device 24, and the tube 28 is deformed into a flat and small shape in a contracted and crushed state. The support of the flexible sheet 30 by the spirally wound tube 28 is released.

Also, a helical tube deformed small
The core material 27 having the core 28 is pulled out and released, and the flexible sheet 30 is pulled out from the through hole B formed in the concrete product main body A and the insertion holes 4 of the front and rear end plates 3 to release the mold. Also, by removing the mold 1 in the same manner as in the above-described embodiment, a concrete product main body A in which the through holes B are formed can be obtained.

The inner wall surface C of the through hole B formed in the concrete product main body A is formed on the spiral supporting portion 30a of the flexible sheet 30 supported by the outer peripheral portion of the spiral tube 28.
Further, the helical tube 30 is formed on the helical arc-shaped surface 30b of the flexible sheet 30 that is not supported by the outer peripheral portion of the helical tube 28 into a smooth arc-shaped uneven surface D along the axial direction.

Therefore, when the flexible sheet 30 is supported by the tube 28 spirally wound at a winding pitch with a predetermined wide interval around the outer peripheral portion of the core 27, The inner wall surface C of the through hole B of the concrete product main body A is formed into a smooth arc-shaped uneven surface D at a wide pitch along the axial direction in accordance with the winding pitch of the tube 28.

Then, the concrete product body A is
For example, when the cable is used as a buried groove for installing the cable, when the cable is drawn into the through-hole B, the contact area between the cable and the inner wall surface C of the through-hole B is small, the frictional resistance is small, and the cable is excessively large. The cable is easily pulled into and installed in the through hole B of the concrete product body A without applying tension.

The flexible sheet 30 is wound around the outer peripheral portion of the core 27 by a tube 28 spirally wound at a winding pitch smaller than the winding pitch of the buried groove penetrating the cable.
Is supported, the inner wall surface C of the through hole B of the concrete product main body A according to the winding pitch of the tube 28 is
It is formed into an arc-shaped uneven surface D at a narrow pitch along the axial direction. And when the flexible sheet 30 is supported by the tube 28 spirally wound in a state of contact with each other,
The arc-shaped uneven surface D is formed at an extremely small pitch along the axial direction, and the arc-shaped uneven surface D is molded in a state almost entirely straight.

Next, in the embodiment shown in FIGS. 6 to 8, the hole-formed body 6 comprises a tube 28 spirally wound at a predetermined winding pitch on the outer periphery of the core 27. The case where the outer peripheral portion of the hollow core body 29 is covered with the cylindrical flexible sheet 30 has been described.
Is a hollow core body comprising a core core material 27 and an expandable / contractible tube 28 spirally wound around an outer peripheral portion of the core core material 27 without using the tubular flexible sheet 30. 29 may be used.

In this case, a hollow core 29 composed of a tube 28 is provided around the outer periphery of the core 27,
The helical coil 29 is spirally wound at a position where it is in close contact with each other when it is expanded into a hard rod shape by the pressure fluid, and the outer peripheral surface of the helically wound hollow core body 29 is expanded at the time of expansion. An arc-shaped uneven surface along the axial direction may be formed.

Then, a pressurized fluid is supplied into a hollow core body 29 composed of a tube 28 spirally wound around the outer peripheral portion of a core core material 27 in the same manner as in the above-described embodiment. By expanding the hollow core body 29 composed of the tube 28 into a hard and round rod shape with the fluid, the hollow core body 29 is in close contact with the side surfaces thereof along the outer peripheral portion of the core core material 27. In addition to being joined in a liquid-tight state, the outer peripheral surface of the spiral hollow core body 29 is formed into an arc-shaped uneven surface along the axial direction.

In the same manner as in the above-described embodiment, the hole-formed body 6 is disposed in the mold 1, and the helical hollow core body 29 of the hole-formed body 6 is surrounded by concrete. And the inside wall C of the through hole B as a hollow portion formed in the concrete product body A is formed into a spiral hollow core.
29 is formed into an arc-shaped uneven surface D along the axial direction at the arc-shaped uneven surface formed on the outer peripheral surface.

Next, in each of the above-described embodiments, both ends of the hole-formed body 6 are inserted into the insertion holes 4 of the end plate 3 in front of and behind the mold 1 to be supported. Although the main body a has been described the case of forming a through-hole B which is open at both ends, not limited thereto, the hollow portion in the concrete product body a does not penetrate an opening only one end using the holes molded 6 B may be formed.

In this case, a part of the hole-formed body 6 of each of the above embodiments is protruded into the mold 1 from the insertion hole 4 of the one end plate 3 of the mold 1, and is inserted into the mold 1. Projected hole molded body 6
Is supported by a plurality of reinforcing bars arranged and fixed in the mold 1 in the same manner as in the above-described embodiments.

Further, the hole-formed body 6 is supported by the insertion hole 4 of the one end plate 3 and a plurality of rebars, and the hollow cores 8 and 29 of the hole-formed body 6 are expanded by a pressurized fluid. Then, concrete is poured around the hollow cores 8, 29 of the hole-formed body 6 protruding into the formwork 1 and cured for a required time, so that the concrete product body A as shown in FIG. In addition, a hollow part B which does not penetrate only one end face is formed in the concrete product main body A. The inner wall surface C of the hollow portion B of the concrete product main body A, which does not penetrate, is formed into an arc-shaped uneven surface D along the axial direction.

In the case of forming a non-penetrating hollow portion B having only one end surface opened in the concrete product main body A,
A part of the hole-formed body 6 is directly inserted into the concrete casting portion without being inserted into the insertion hole of the side plate such as the one end plate 3 of the formwork 1, and the concrete product body is formed in the same manner as in the above-described embodiment. The inner wall surface C of the hollow portion B which does not penetrate and whose one end portion is open to A may be formed on the arc-shaped uneven surface D along the axial direction.

The concrete product main body A is formed with a hollow portion B which does not penetrate the anchor bolts and the reinforcing bars and the like, and the anchor bolts and the reinforcing bars and the like are mounted in the hollow portions B via concrete. Thereby, anchor bolts, reinforcing bars, and the like are securely prevented from falling out of the concrete that bites into the arc-shaped uneven surface D of the inner wall surface C and is solidified.

Next, in each of the above-described embodiments, the case where the through-hole B as a hollow portion in which the inner wall surface C is formed in the concave-convex surface D with an arc-shaped section in the concrete product main body A has been described. Instead, for example, as shown in FIG. 10, a concrete product main body A may be formed with a through hole B having an inner wall surface C formed into an arc-shaped uneven surface D and having a plurality of open end surfaces.

In this case, a plurality of hole forming bodies 6 are set on the mold 1 at predetermined intervals. Then, concrete is poured into the mold 1 and cured for a required time in the same manner as in each of the above-described embodiments, so that the concrete product main body A has an inner wall C formed with an arc-shaped uneven surface D in cross section. The through hole B is formed at the same time.

When a plurality of through-holes B having an inner wall surface C having an arc-shaped uneven surface D are formed in the concrete product main body A, each core material 7, 27 is formed in the same manner as in the above-described embodiments. May be a round bar having a circular cross section. However, as shown in FIG. 10, the round bar cores 7 and 27 and a flat core core 33 formed in a flat shape are used. The tube 28 is spirally wound around the flat core 33, and the outer peripheral portion of the spirally wound tube 28 is covered with the flexible sheet 30 to form the hole-formed body 6. You may.

Then, the hole-formed body 6 having the flat core material 33 is set in the mold 1 in the same manner as in the above-described embodiments, and concrete is poured and cured for a required time so that the concrete is cured. The product body A has a plurality of round holes and an arc-shaped uneven surface D having an inner wall surface C having an arc-shaped uneven surface D.
Each of the flat through holes E as hollow portions having the inner wall surfaces C is simultaneously formed.

Accordingly, the core members 7, 2 formed in various shapes such as the round core members 7, 27 and the flat core members 33, etc.
By forming each of the hole moldings 6 using the members 7 and 33, the inner wall surfaces C of the through holes B and E of various shapes formed in the concrete product main body A have an arc-shaped uneven surface D along the axial direction. It is molded.

Next, in each of the above embodiments, the case where the linear through holes B and E are formed in the concrete product main body A has been described. However, the present invention is not limited to this. The through-holes B and E formed in the arc-shaped uneven surface D along the axial direction may be formed in a curved shape. For example, as shown in FIG. It is also possible to form a through-hole F as an L-shaped hollow portion that is bent into a substantially L-shape formed on the arc-shaped uneven surface D along the cross-section.

In this case, a bendable flexible core material 34 is used. As the flexible core 34, for example, a flexible tube that can be sufficiently bent or a flexible tube 35 as a flexible body made of rubber or the like may be used. Then, the flexible tube 35 is bent into a substantially L-shape, and the hollow cores 8, 29 are provided along the outer peripheral portion of the flexible tube 35 in the same manner as in the above-described embodiments. A molded body 6 is formed, around the hollow cores 8 and 29 of the hole molded body 6 or a hollow core.
By pouring curing concrete around the flexible sheet 30 coated with 29, is formed in cross section arcuate uneven surface D along the inner wall surface C in the axial direction in the concrete product body A and concrete product body A A through hole F is formed as a substantially L-shaped hollow portion.

Therefore, in each of the above embodiments, if necessary, the linear cores 7 and 27 and the flat cores 33
In addition, by selecting and using a flexible core 34 composed of a bendable flexible tube 35 or the like, the inner wall surface C of the concrete product main body A is formed along the axial direction along the arc-shaped uneven surface D.
The curved through holes F are formed by bending the straight through holes B and E and the inner wall surface C formed in the above-described manner into an approximately L-shape or the like formed on the arc-shaped uneven surface D along the axial direction.

The through-holes B, E, and F formed in the concrete product body A are, for example, drainage holes in L-shaped retaining walls, manholes, fire prevention water tanks, box culverts, rainwater basins, etc. Can be molded into various products, such as branch holes for joints and the like and joint holes for concrete products.

Next, in each of the above-described embodiments, one linear core core 7, 27, a flat core core 33, and a bendable flexible core 34 are provided on the outer periphery. Tube28
Has been described in a spiral manner, but the present invention is not limited to this. For example, linear core members 7 and 27 and a flat core
For example, on the outer peripheral portion of the bendable flexible core 34 and the core 34, for example, the cores 7 and 27 and the flat core 33
In addition, a plurality of independent expandable and contractible annular tubes are fitted to each other at predetermined intervals in accordance with the length of the flexible core material 34, and are arranged and supported. The hole-forming body 6 may be formed by connecting and connecting one common inflatable communication tube to each of the annular tubes. The fluid supply / discharge means 19 is connected to the drawing end of the communication tube. Other configurations and the method of molding the concrete product are the same as those in the above-described embodiments.

In the concrete product body A molded by using the hole molded body 6 configured as described above, independent annular concave portions and annular convex portions are successively formed successively and repeatedly in the longitudinal direction thereof. The concrete product body A has an inner wall surface C extending along the axial direction and an arc-shaped uneven surface D in section.
Are formed, and through holes F having a substantially L-shape are formed.

Next, in each of the above-described embodiments, the case where the hole forming body 6 is provided in the mold 1 to form the concrete product body A having the through holes B, E, F and the hollow portion B which does not penetrate. However, the present invention is not limited to this, and the hole-formed body 6 can be directly applied to cast-in-place of concrete or the like without using the formwork 1.

Then, concrete is cast in place. For example, through holes B,
E, F and the hollow part B which does not penetrate are easily molded. Thus, the through holes B, E, and F can be used as guide holes through which cables such as communication lines and power lines and water and sewage pipes and gas pipes are inserted. Thus, in this specification, the concrete product main body A is similar to a buried groove such as an electric wire common groove,
For example, it includes not only a block-shaped product that can be transported in a predetermined size such as several meters, but also a portion such as a foundation of a building.

[0093]

According to the first aspect of the present invention, the outside of the core material is provided.
When expanding to the periphery, the outer peripheral surface is arc-shaped in section along the axial direction
A flexible hollow core that forms
A pressure fluid is supplied to the core to expand the hollow core.
And concrete around the hollow core.
Cross section of the outer peripheral surface of the hollow core by casting and curing
One end and the other end, such as entrance and exit,
A hollow part with no difference in hole diameter between the end and the inner end
The concrete product body can be easily molded,
In addition, the inner wall surface of the hollow part formed in the concrete product body is formed into an arc-shaped uneven surface along the axial direction .
When a cable or the like is inserted into this hollow portion, the contact area with the inner wall surface of the hollow portion is small, so that the frictional resistance is small, an excessive pulling tension is not required , and the pulling operation is easy. When anchor bolts, reinforcing bars, and the like are mounted in the hollow portion, they can be reliably retained and supported, and therefore, it is possible to provide a concrete product that is preferable as a buried groove such as an electric wire common groove.

Also, the pressure fluid in the hollow core is sucked.
The hollow core can be easily shrunk by shrinking the hollow core.
The mold can be released, and the pressure flow into the hollow core
Supply and suck the body to easily expand and contract the hollow core
And the mold release time can be reduced.
It can be significantly reduced.

Also, the hollow core is pulled out and released.
This allows the hollow core to be easily exposed and
The trocars can be easily removed. Accordingly
To make the inner wall surface an arc-shaped uneven surface along the axial direction.
Improve the productivity of concrete products that form voids
Can be.

According to the second aspect of the present invention, the first aspect of the present invention is provided.
Hollow core made of expandable and contractible tube
By spirally winding the body around the outer periphery of the core material,
The inner wall surface of the hollow part of the concrete product
This makes it possible to easily form an arc-shaped uneven surface in a spiral shape.
The hollow core is spirally wound around the outer periphery of the core.
Even when turned, it can be easily molded by supplying and suctioning pressure fluid.
Can be released and released.

According to the third aspect of the present invention, the second aspect of the present invention is provided.
In addition to the effect of the above, the outer periphery of the spirally wound hollow core body
Is covered with a flexible sheet to obtain a hollow core body.
The flexible sheet is formed by the winding pitch in which the
It can be bent and molded, and the inner wall surface of the hollow part is
Can be formed on the smooth arcuate uneven surface along the
You.

According to the fourth aspect of the present invention, concrete
It is suitable for the embodiment of the molding method of the product, and its configuration is simple
, Easy to assemble and release operations, cost merit
And concrete products have the same or different shapes.
The number of hollow parts can be easily molded,
For molding joint grooves etc. to insert and install various insertion materials
To provide concrete product molding equipment suitable for
it can.

According to the invention of claim 5, according to the invention of claim 4,
In addition to the effects of
The tube is made by core
Easy to form a hole by spirally winding along the outer periphery of the material
Can be configured, this tube is expandable and contractable
Easy to match and release.

According to the invention of claim 6, according to the invention of claim 5,
In addition to the effect of the above, a winding pin for spirally winding the hollow core body
The outer circumference of the hollow core is flexible
Parts can be reliably covered over the entire length, and this flexible
That the concrete sheet adheres to the core
It can be reliably prevented, and the medium can be adjusted according to the winding pitch of the hollow core.
The inner wall surface of the cavity is smooth in the axial direction along the arc
Can be formed on the surface.

According to the invention of claim 7, according to claims 4 to 6,
In addition to the effects of any one of the inventions, the core material can be bent
Because it consists of a flexible body,
In addition to being able to mold a straight hollow part into the product,
For example, a curved hollow portion that is bent into a substantially L-shape
It can be simply molded, its release operation is easy,
Therefore, it is versatile and has high cost merit overall.
Can provide molding equipment for concrete products
You.

[Brief description of the drawings]

FIG. 1 is a perspective view in which a part of a concrete product is omitted.

FIG. 2 is an enlarged sectional view of a part of the above.

FIG. 3 is a perspective view of a concrete product molding apparatus showing one embodiment of the present invention.

FIG. 4 is an enlarged cross-sectional view showing a molded state in which the hollow core body of the above-mentioned hole molded body is expanded.

FIG. 5 is a cross-sectional view showing a mold release state in which the hollow core of the hole-formed body is contracted.

FIG. 6 is a perspective view of a concrete product molding apparatus showing another embodiment of the present invention.

FIG. 7 is an enlarged cross-sectional view showing a contracted state of a tube of the above-mentioned hole-formed body.

FIG. 8 is an enlarged cross-sectional view showing a molded state in which the tube of the above-mentioned molded hole is expanded.

FIG. 9 is a perspective view in which a part of a concrete product molded in another embodiment is omitted.

FIG. 10 is a perspective view in which a part of a concrete product molded in another embodiment is omitted.

FIG. 11 is a perspective view in which a part of a concrete product molded in another embodiment is omitted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Formwork 6 Hole molding 7 Core core 8 Hollow core 19 Fluid supply / discharge means 27 Core core 28 Tube 29 Hollow core 30 Flexible sheet 33 Flat core 34 Flexible Core core material 35 Flexible tube A Concrete product body B, E, F Hollow portion C Inner wall surface D Sectional arc-shaped uneven surface

Claims (7)

(57) [Claims] Claims: 1. A method for manufacturing a concrete product body, comprising :
The outer periphery of the core material that forms a hollow part that is open at one end
When the part expands, the outer peripheral surface has an arc-shaped uneven surface along the axial direction
A flexible hollow core that forms
The hollow core body holding a core core material fitted with a core body,
In a state where the hollow core is expanded with a pressure fluid.
Pour concrete into the enclosure and cure it to form a concrete product.
Mold and suck the pressure fluid to shrink the hollow core
And the hollow core body and the core material
A method for molding a concrete product , wherein the method is performed by pulling out from the concrete product and releasing the mold . 2. The expansion / contraction in which the hollow core is closed at one end.
Formed with a possible tube, hollow consisting of this tube
2. The method for molding a concrete product according to claim 1 , wherein the core is wound spirally around the outer periphery of the core . 3. The spirally wound hollow core body is
3. The method of molding a concrete product according to claim 2, wherein the outer peripheral portion is covered with a flexible sheet . 4. A mold, and a molded hole provided in the mold.
And a fluid supply / discharge means, wherein the hole-formed body is formed at least in a concrete product.
Also, a core material forming a hollow part opened at one end surface,
The outer peripheral part was fitted to the core and expanded along the axial direction when expanded.
A flexible hollow core formed on the concave-convex surface with an arc-shaped cross section.
The fluid supply / discharge means is provided in a flexible hollow shape of the hole-formed body.
While supplying pressure fluid to the child body, this pressure fluid is
Molding equipment for concrete products characterized by suction
Place . 5. The hollow core of the hole-formed body is made of a core material.
Expandable tube spirally wound along the outer circumference
The apparatus for molding a concrete product according to claim 4, wherein the apparatus is formed by the following. 6. An outer peripheral portion of a spirally wound hollow core body.
6. The concrete product molding apparatus according to claim 5, further comprising a flexible sheet for covering the concrete product. 7. The core material is made of a bendable flexible body.
Made, it molding apparatus of the concrete product according to claim 4 or 6 either serial <br/> mounting characterized.