JP2000006127A - Method for forming fitting hole of concrete molded article and male mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for forming a fitting hole of a concrete molded article and a male mold wherein a fitting hole into which a hooking part provided on the side end of an elastic seal material is inserted in a concrete molded article such as a side water path, a box culvert, a retaining wall and an exterior wall panel is highly accurately formed and deviation on the fitting posture of a male mold main body is not generated and elastic recovery is rich and the life can be extended and maintenance and control are easily performed in relation to the method for forming the fitting hole of the concrete molded article and the male mold. SOLUTION: A hollow projected part 7b formed on the apex of a male mold main body 7 which is formed of an elastic material such as a rubber and can be fitted at a required position in a form 1 is expanded by making a pressurized fluid L flow thereinto when concrete is filled and the pressurized fluid L is made to flow out to reduce the pressure when the concrete is aged and solidified and in addition, when the concrete molded article is released from the mold, it is shrunk by making the pressurized fluid flow out to form the concrete molded article A with a highly accurate fitting hole.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a mounting hole in a concrete molded product and a male mold, for example, an underground buried structure such as a side groove, a U-shaped groove, a box culvert, a sewer pipe, a tunnel, a retaining wall, and the like. Locking parts provided at the side ends of an elastic sealing material formed of an elastic material on a concrete molded product of a building material such as a civil engineering material, an outer wall panel, an inner wall panel, a ceiling panel, a floor panel, a slab plate, etc. It is optimally used to form a mounting hole for inserting

[0002]

2. Description of the Related Art Conventionally, concrete materials, such as civil engineering materials, outer wall panels, inner wall panels, ceiling panels, and floor structures such as underground structures such as gutters, U-shaped grooves, box culverts, and underground structures such as retaining walls. FIGS. 11 and 12 show a molding die for inserting a locking portion provided at a side end of an elastic sealing material into a concrete molded product of a building material such as a panel to form a mounting hole for fastening in a watertight manner. Some of them have such a male mold or a male mold as shown in FIG. In these male molds, a male mold body a formed of an elastic material such as rubber or synthetic resin has a mold b formed of a plate material having a smooth surface such as an iron plate or a hard synthetic resin plate. As shown in FIG. 11, it is bonded to the side surface using an adhesive c,
Or protrudes from the bolt d were implanted in male body a as shown in FIG. 13 from the insertion hole b ₁ of the form b, it was formed in the like to fix at the nut e. Male body a
Forms a protrusion a ₂ of the large-diameter forming the substantially circular section on the front end of the mounting base portion a ₁ of the tapered-off. Then, concrete is poured into the formwork b, cured, solidified and released from the mold, for example, gutters, U-shaped grooves, underground buried structures such as box culverts, civil engineering materials such as retaining walls, outer wall panels, A concrete molded product A such as an inner wall panel, a ceiling panel, or a floor panel is formed. The release time of the concrete moldings A, the bonding surface A ₁ of the concrete moldings A, A by a male body a made of an elastic material such as rubber is pulled out is exhibited stretchability concrete moldings A, A It was to form a substantially circular section of the mounting hole g for the back of the opening g ₁ facing the ₁ to insert the elastic sealing material.

[0003]

FIG. 11 and FIG.
In the conventional example shown in FIG. 13, the mounting posture of the male main body a mounted on the inner side of the mold frame b tends to be deviated, and the elastic restoring property of the male main body a is not uniform every time it is used. A high-precision mounting hole g having a desired shape and dimensions could not be formed in the concrete molded product A. The mounting hole g formed in the concrete molded product A has a cross-sectional shape of a concrete molded product in order to surely secure the locking portion of the elastic seal material and to ensure watertightness with respect to the elastic seal material. a, because it is formed behind the cross-section substantially circular large-diameter openings g ₁ of Subomari previously facing the bonding surface a _1, a ₁ of a mutual, concrete curing, mounting holes g upon release after solidification to extract the male body a, narrow constricted portion k of the communication設個office opening g ₁ with respect to the mounting hole g, protrusion a ₂ of the large diameter of the male body a to k are engaged from As a result, there was a problem that the male main body a could not be smoothly removed from the mounting hole g. Therefore, molding the concrete molded product A is inefficient and takes a lot of molding time, which is inefficient, and the molding cost of the concrete molded product itself has become expensive. Since the strong tensile force for release is applied to the projecting portion a ₂ of the male body a, the number of uses of the male increases, the male body a by mechanical fatigue
Of the protrusion a ₂ is broken, replace it with a new one male body a Shinazu, maintenance, have required a lot of the time and expense to management. In addition, since a gap is easily formed between the male body a and the mold b after the male body a is attached to the mold b, concrete invades into the gap when the concrete is poured and cures,
Since concrete debris remains even after releasing from the mold after solidification, it was not possible to form the mounting hole g with high precision in the concrete molded product A, and the surface of the concrete molded product A could not be formed neatly.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional inconvenience, and there is no deviation in the mounting posture of a male body attached to the inside of a formwork. It is reliable without any deterioration, has low mechanical fatigue, prolongs the life, is easy to maintain and manage, and can produce a concrete molded product with a beautiful surface with high-precision mounting holes without taking much time. An object of the present invention is to provide a method for forming a mounting hole of a concrete molded product which is efficiently molded and whose production cost is low, and a male mold.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a first aspect of the present invention is to attach a male mold body formed of an elastic material such as rubber to a desired position inside a mold, and to attach the mold to the mold. A step of forming a mounting hole in a concrete molded product by pouring a pressurized fluid into a hollow protrusion provided at the tip of the male main body at the time of casting concrete and inflating the protrusion into a desired shape; After the concrete is poured, a step of allowing a desired amount of pressurized fluid to flow out of the protruding portion and curing and solidifying the concrete molded product under reduced pressure; Then, the protruding portion is withdrawn to remove the protruding portion from the mounting hole and release the concrete molded product.

According to a second aspect of the present invention, a pressurized fluid is injected into a large-diameter hollow projection formed at the tip of a male mounting base portion having a tapered male portion mounted in a mold. By inflowing through the flow passage, the protruding part is expanded by pressurization at the time of concrete casting to form a mounting hole in the concrete molded product, and when releasing the pressurized fluid from the protruding part, the protruding part , The protruding portion is withdrawn from the mounting hole in the axial direction and released from the mounting hole.

According to a third aspect of the present invention, there is provided a male body formed of an elastic material such as rubber and attached to a desired position in a mold frame, and a male body formed at the tip of the male body and being added at the time of placing concrete. When a pressurized fluid is introduced and expanded, a desired amount of pressurized fluid is reduced during curing and solidification of the concrete in the concrete molded product, and a hollow protrusion is formed to allow the pressurized fluid to flow out and shrink when the concrete molded product is released from the mold. A means consisting of a shape part was adopted.

According to a fourth aspect of the present invention, in the third aspect, the male mold main body has a tapered mounting base portion mounted on a mold and a pressurized fluid formed at a tip end of the mounting base portion. Or a large-diameter hollow protrusion that can be expanded and contracted by flowing out, and the inside of the male body is communicated with the protrusion to allow the pressurized fluid to flow in or out. A route is provided.

According to a fifth aspect of the present invention, in the third aspect, a position regulating projection is provided on the top of the projecting portion, and the position regulating projection is in a direction in which the male mold body is removed when the concrete molded product is released from the mold. Is adopted in accordance with the above.

According to a sixth aspect of the present invention, in any one of the third and fourth aspects, the protrusion has an outer shape of any one of a substantially circular cross section, a substantially elliptical cross section, and a substantially triangular cross section. Means is adopted in which a hollow portion that can be expanded or reduced is formed inside the protruding portion.

According to a seventh aspect of the present invention, the pressurized fluid according to any one of the third and fourth aspects is characterized in that the pressurized fluid is either air or gas, or water or oil liquid. We adopted the means of being.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the invention. 1 to 10 show an embodiment of the present invention. Reference numeral 1 denotes a mold. The mold 1 is formed to have an inner shape that matches the outer shape of the concrete molded product A to be molded. In this embodiment, a side groove 2 is formed as the concrete molded product A in FIG. Formed by the bottom plate 3, the side plates 4 and 4 disposed opposite to the left and right side surfaces of the bottom plate 3, and the front plate 5 and the rear plate 6 disposed opposite to the front and rear of the side plates 4 and 4, respectively. After the concrete is cast and cured and solidified, the bottom plate 3
On the other hand, the side plates 4, 4 and the front plate 5 and the rear plate 6 are formed so as to be disassembled and assemble. M is a concrete molded product A
This is a nesting member which is installed at a desired interval K in the mold 1 in order to form the mold. The bottom plate 3, the side plates 4 and 4, the front plate 5 and the rear plate 6 are configured to be easily disassembled and can be assembled using a connection fitting such as a hinge not shown.

Reference numeral 7 denotes a desired position inside the formwork 1, for example, in the present embodiment, a front and rear surface of the side groove 2 as the concrete molded product A, which can be detachably protruded into a substantially U-shaped front when the concrete molded product A is molded. In this embodiment, the male body 7 is made of rubber or flexible so as to have a waterproof property by connecting the side grooves 2 when the side groove 2 is laid, as shown in FIG. front substantially U-shaped mounting hole 2a for causing the fastening insert the locking portion S _1, S ₁ provided on both sides longitudinally of the sealing material S made of an elastic material such as synthetic resin having, 2a
To the openings 2a ₁ facing the joining surfaces 2b, 2b of the side grooves 2, 2.
It is intended to form the back of the 2a _1. The male main body 7 has a tapered male mounting base 7a and a large-diameter hollow shape formed at the tip of the mounting base 7a as shown in the figure, for example, whose outer shape is substantially circular in cross section. And the projection 7b. 7a ₁ is a engagement recess as an engagement means formed in correspondence with the left and right outer sides of the mounting base portion 7a.

The protruding portion 7b shown in FIGS. 1 and 2 is merely an example, and has an outer shape of a substantially circular cross section, an elliptical cross section or a substantially triangular cross section, and a hollow inside. part 7b ₁ is a hollow shape provided. The hollow protruding portion 7b is used when the concrete C is cast to cast the concrete C to form the concrete molded product A by the mold 1 as shown in FIGS. L flows into the protruding portion 7b
Is formed into a desired shape to form a mounting hole 2a having a desired shape and a desired size in the concrete molded product A. After the concrete is cast, concrete C is applied to the concrete molded product A as shown in FIG. At the time of curing, such as steam curing, and solidification, a desired amount of the pressurized fluid L is discharged from the projecting portion 7b such that the shape-retaining property is maintained, thereby curing and solidifying the projecting portion 7b in a reduced pressure state. As shown in FIG. 9, when the concrete C is cured and solidified, the pressurized fluid L flows out from the protruding portion 7b and shrinks, thereby removing the protruding portion 7b from the mounting hole 2a to form concrete. 1 and 7 and expandable or collapsible hollow portion 7b ₁ as shown in FIG. 9 is formed to make reliably release work of goods a. 7c is a flow path provided so as to communicate with the hollow portion 7b ₁ in male body 7,
It has either flowing a pressurized fluid L with respect to the hollow portion 7b _1, or a pressurized fluid L to be drained through the passage 7c. As described above, the inside of the projection 7b is depressurized during curing and solidification of the concrete because the projection 7b expands due to steam heat due to steam curing and heat due to hydration of the concrete C. This is for preventing rupture of the mounting hole 2a and for improving the manufacturing accuracy of the mounting hole 2a. As the pressurized fluid L, either air or gas, or water or oil is used. The pressurized fluid L flows into, out of, or stops with respect to the protruding portion 7b by suction and discharge by a pump (not shown), and further by stopping. Is controlled so that the manner of expansion of the outer volume of the protruding portion 7b differs in size according to the size of the mounting hole 2a of the concrete molded product A to be molded. In addition, the sealing time of the pressurized fluid L in the protruding portion 7b, that is, the cement,
The length of the concrete C is controlled in accordance with the curing and solidification time of the concrete C which varies depending on the mixing ratio of aggregates such as sand and gravel.

Reference numeral 7d denotes a conical position regulating projection provided on the top of the projecting portion 7b, for example. The position regulating projection 7d is used when the concrete molded product A is released (see FIG. 9). Is provided in accordance with the extraction direction A. The position restricting projection 7d is provided so as to coincide with the extracting direction A of the male main body 7 because a pressurized fluid is applied to the concrete C to be cast into the mold 1 to form the concrete molded product A. The protrusions 7b swelled by the inflow of L are locked at a predetermined position in the concrete C against the compression pressure of the fluid concrete C and the expansion pressure of the concrete C during curing and solidification. In addition, when the mounting hole 2a having a desired shape and a high precision of a desired dimension is formed by uniform swelling (see FIGS. 6 and 7), a protrusion is generated when the concrete molded product A is released (see FIG. 9). This is for facilitating the withdrawal from the mounting hole 2a by deflating the shape portion 7b without requiring excessive force.

The mold 1 comprises a mold forming substrate 8 disposed outside the mold 1 and a male body 7 inside the mold forming substrate 8 (the upper surface in FIGS. 1 and 2). Desired plural pieces which are divided and slidably overlapped in the opposite direction or the opposite direction, for example, three pieces each on the left and right sides with respect to the male body 7, a total of six internal form forming plates 9 ′ a, 9 ′ b, 9'c; 9a, 9
b, 9c.

The male frame 7 is attached to the male main body 7 by a total of six left and right three slidable in opposing or intersecting directions with respect to the longitudinal direction I of the male main body 7. Internal form forming plates 9'a, 9'b, 9'c; 9 arranged on the form forming substrate 8 so as to be divided and superimposed.
a, 9b and 9c sandwich the mounting base portion 7a and the inner end edges 9'b _{1 of} the internal form forming plates 9'b and 9b located at a predetermined number of steps, in FIGS. 1 and 2, the second step. , 9b ₁ are locked in the engaging recesses 7a ₁ , 7a ₁ as engaging means, and the male main body 7 formed of an elastic material such as rubber is fixed to the mold 1.

One embodiment of the male mold according to the present invention is constituted as described above. A method of forming the mounting hole 2a of the concrete molded article A using the male mold will be described in the order of steps together with the operation. First, as a first step, in order to form the side groove 2 as a concrete molded product A, an interval formed between the nested member M installed in the assembled mold 1 and the mold 1 as shown in FIG. Pour concrete C into K. Thus, when the concrete C is poured into the formwork 1,
FIG. 7 shows the inside of a hollow projection 7b provided at the tip of the male body 7.
As shown in (1), the mounting hole 2a is formed in the concrete molded product A by flowing the pressurized fluid L to expand the protrusion 7b into a desired shape and a desired size.

At this time, the male body 7 is provided on the top of the projection 7b.
Is provided with a conical position regulating projection 7d in accordance with the extraction direction A, so that the protruding portion 7b of the male mold body 7 is moved relative to the concrete C cast into the mold 1 by the position regulating projection 7d. As shown in FIG. 6, the mounting position is locked at a predetermined position without causing bias in the mounting position against the expansion pressure of the concrete C at the time of compression, curing, and solidification, so that it does not move carelessly. When the pressurized fluid L flows into the protruding portion 7b by driving a pump (not shown), the outer shape is uniformly and evenly expanded and the outer shape is substantially circular in cross section as shown in FIG. It has a desired shape such as a shape and a substantially triangular cross section. In addition, the amount of the pressurized fluid L flowing into the protruding portion 7b is controlled by controlling the driving time and the driving speed of the pump so as to adjust the degree of expansion of the outer volume of the protruding portion 7b by adjusting the size thereof. Of the mounting hole 2a can be set. In addition, the filling time of the pressurized fluid L into the protruding portion 7b, that is, from the inflow start time to the outflow end time, depends on the curing and solidifying time of the concrete C which varies depending on the mixing ratio of the aggregates such as cement, sand, and gravel. By controlling the length, an optimum concrete molded product A can be formed.

Next, as a second step, the concrete C cast in the previous step is placed in a curing room at 60 ° C. to 7 ° C.
By curing and solidifying by steam curing at a room temperature of about 0 ° C., a concrete molded product A having a desired shape and a highly accurate mounting hole 2 a having a desired size can be formed. At this time, as shown in FIG. 8, a desired amount of pressurized fluid L is discharged to the extent that the shape retention of the protruding portion 7b is maintained, and the inside of the protruding portion 7b is depressurized.
Curing and solidifying. As described above, the pressure in the projecting portion 7b is reduced in the curing and solidifying processes of the concrete C because the projecting portion 7b expands due to steam heat due to steam curing and heat due to hydration of the concrete C. This is for preventing the rupture of the portion 7b and for forming the mounting hole 2a having high production accuracy in the concrete molded product A. The mounting holes 2a are used to connect the concrete moldings A to be joined,
A large-diameter section is formed substantially in the back of the constricted openings 2a ₁ , 2a ₁ facing 2b.

Next, as a third step, when the concrete C is cured and solidified, the pressurized fluid L flows out from the protruding portion 7b to deflate the protruding portion 7b, so that the formed mounting hole 2a is removed. The protrusion 7b is pulled out, and the concrete molded product A is released from the mold 1 (see FIG. 9). The protrusion 7b of the male body 7 is a concrete molded product A
Collapses behind the opening 2a ₁ facing the bonding surface 2b of the constricted portion k becomes continuous設個office opening 2a ₁ with respect to the mounting hole 2a formed in the large diameter, narrower than the gap l between the k since, in the case of forming the mounting hole 2a of the tapered-off of a large diameter at the back of the opening 2a ₁ of the concrete moldings a, in the normal male body 7
Even when it is difficult to remove the protruding portion 7b from the mounting hole 2a, a strong tensile force is forcibly applied to the protruding portion 7b of the male body 7 at the time of release, as shown in FIG. The protruding portion 7b can be smoothly removed from 2a, and the release operation of the concrete molded product A can be performed quickly and reliably.

Further, since the conical position regulating projection 7d is formed on the top of the protruding portion 7b in accordance with the extracting direction A,
Protrusion 7b is sampling is smoothly performed in the protrusion 7b without being caught in the mounting hole 2a and the opening 2a ₁ when deflated.
Moreover, since an excessively strong tensile force does not need to be applied to the protruding portion 7b at the time of removal, even when the male molded body 7 is frequently used in molding the concrete molded product A, the male molded body 7 may be mechanically fatigued or stressed. No degradation such as breakage or cracking of the protruding portion 7b is eliminated. For this reason, when molding the concrete molded product A, the male mold body 7 has a low mechanical fatigue and is structurally robust through a series of molding steps such as a concrete C placing step, a curing / solidifying step, and a releasing step. , The service life is extended even when used repeatedly, and the life is extended.

The male body 7 is attached to the front and rear plates 5 and 6 on the molds 1 and 1 by mounting the male body 7 on the inside (upper surface in FIGS. Desired plural sheets which are slidably divided in an opposing direction or a separating direction so as to intersect in the longitudinal direction I of the main body 7 and are superimposed, and in FIG. 1 and FIG. 9a, 9b and 9c hold the mounting base 7a of the male mold body 7 between the internal formwork plates 9'a, 9'b and 9'c; , 9'c; 9a, 9b, 9c
Number stage given of the internal formwork construction plate 9'b located the second stage, provided inner edge 9'b _1, 9b ₁ and 9b on the left and right sides of the mounting base portion 7a of the male body 7 The male main body 7 is mounted so as to protrude inside the mold 1 by being locked in the engagement recesses 7a ₁ , 7a ₁ as the engagement means.

For this reason, the male body a is bonded to the inner surface of the mold b by using an adhesive c as shown in FIG. 11, or a bolt d is implanted in the mold b as shown in FIG. As in the conventional male main body a in which the male main body a is fixed to the inside of the mold frame b by screwing the nut e to the male main body a, there is no gap between the male main body 7 and the mold frame 1. The concrete residue after curing and solidification does not enter the gap. Accordingly, the mounting hole 2a with high precision can be formed in the concrete molded product A, and the surface of the concrete molded product A has a beautiful finish.

When the form 1 is used many times and the male body 7 is worn or cracked and becomes old and needs to be replaced with a new one, the form structure arranged outside is used. A plurality of internal mold forming plates 9'a, 9 '
b, 9'c; 9a, 9b, 9c are slid so as to be separated from each other to the left and right, so that the inner frame forming plates 9'a, 9'b, 9'c with respect to the mounting base portion 7a of the male main body 7; 9a, 9
b, a predetermined number of stage with releasing the holding of 9c, internal formwork construction plate 9'b located at the second stage as shown in FIGS. 1 and 2, the inner edge of 9b 9'b _1, 9b ₁ Can be pulled out from the engagement recesses 7a ₁ , 7a ₁ as the engagement means to release the engagement. In this way, the male main body 7 that is used many times and becomes old or cracks can be removed from the mold 1.

For mounting the new male body 7 on the mold 1
Are the desired number of internal formwork plates 9'a, 9'b, 9 '
c; 9a, 9c, 9c are opposed to the frame forming substrate 8 in the facing direction.
The male body 7 can be
Holds the mounting base 7a and is positioned at a predetermined number of steps.
Inner edge 9'b of the internal form forming plate 9'b, 9b₁, 9b
₁Recess 7a as an engagement means₁, 7a₁Locked in
By attaching the male body 7 to the inside of the mold 1
Can be. In this way, the replacement work of the new male body 7
Finish the business.

In the first embodiment, in order to attach the male body 7 to the mold 1, the engaging recesses 7a ₁ , 7a ₁ are provided on both left and right sides of the mounting base 7a of the male body 7 as engaging means.
Are formed in the engaging concave portions 7a ₁ , 7a ₁ so as to be slidable on the mold forming substrate 8 in opposition to the internal forming plate 9 ′.
b, it is mounted to the inner edge 9'b _1, 9b ₁ and 9b to be engaged. However, as the engaging means, opposite to the above embodiment, engaging convex portions are formed on both left and right sides of the mounting base portion 7a of the male main body 7, and the engaging convex portions are formed by a plurality of opposing internal molds. Inner edge 9 'of internal component plates 9'a, 9a; 9'c, 9c, which are arranged above and below other than frame component plates 9'b, 9b
a ₁ , 9a ₁ ; 9'c ₁ , 9c ₁ so that the male body 7 can be engaged and received in an engagement recess formed in the recess.
Can be attached to the mold 1.

In each of the above-described embodiments, the internal form forming plates 9'a, 9'b,
9'c; 9a, 9b, and 9c use a total of six sheets, three on each of the left and right sides, but they can be freely increased or decreased.

Further, in the above embodiment, the case where the male mold body 7 forms the side groove 2 as the concrete molded product A has been described. However, the form 1 is not limited to the case where the side groove 2 is formed, but should be formed. Concrete molded product A is U-shaped ditch, box culvert, underground buried structure such as sewer pipe, civil engineering material as outer structure such as tunnel, retaining wall, outer wall panel, inner wall panel, ceiling panel, floor panel, slab board The present invention can also be applied to a case in which a mounting hole for mounting an elastic sealing material is formed in the above manner. The male body 7 is not limited to the case where the mounting hole is formed, and the shape is not limited to the illustrated one.

[0030]

As described above, according to the present invention, a male mold is formed of an elastic material such as rubber, and is mounted on a desired position in a mold frame. When the concrete is cast, the pressurized fluid expands, and when the concrete is cured and solidified, the desired amount of pressurized fluid flows out and the pressure is reduced, and when the concrete molded product is released, the pressurized fluid flows out and shrinks. Since it is formed from a hollow protruding part that is formed, the mounting posture of the male body attached to the inside of the mold is not biased, and the elastic recovery of the male body increases the number of uses. Also, it is ensured without deterioration, the mechanical fatigue is reduced, the life is extended, and the maintenance and management become easy. In addition, a concrete molded product having a clean surface having high-precision mounting holes can be efficiently molded without requiring much time, and the production cost is reduced.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view showing one embodiment of a male mold for a concrete molded product of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a state before the male mold according to the present embodiment is attached to a mold forming substrate.

FIG. 3 is an exploded perspective view illustrating an example of a mold used in the present embodiment.

FIG. 4 is a perspective view showing an example of a concrete molded product similarly molded by a male mold.

FIG. 5 is an enlarged perspective view showing a state in which a sealing material is inserted into a mounting hole formed in the concrete molded product and the concrete molded products are joined to each other.

FIG. 6 is an explanatory enlarged cross-sectional view showing a concrete placing process when a concrete molded product is molded using the male mold of the present embodiment.

FIG. 7 is an explanatory enlarged cross-sectional view showing a molding step, a curing step, and a solidifying step when a concrete molded article is molded.

FIG. 8 is an explanatory enlarged cross-sectional view showing a state in which the concrete product is cured and solidified.

FIG. 9 is an explanatory enlarged cross-sectional view showing a mold release process of a concrete molded product for extracting a deflated protrusion from the mounting hole.

FIG. 10 is an explanatory enlarged sectional view showing the completed concrete molded product.

FIG. 11 is an enlarged sectional view showing an example of a conventional male mold.

FIG. 12 is an enlarged sectional view showing a concrete molded product in which a mounting hole is formed using a male mold.

FIG. 13 is an enlarged sectional view showing another example of the conventional male mold.

[Description of Signs] 1 Formwork 2 Side groove 2a Mounting hole 2a ₁ Opening 2b Joining surface 7 Male main body 7a Mounting base 7a ₁ Engaging recess 7b Projecting portion 7b ₁ Hollow portion 7c Flow path 7d Position regulating protrusion 8 type Frame component board A Concrete molded product C Concrete I Longitudinal direction L Pressurized fluid

Claims (7)

[Claims] A male body formed of an elastic material such as rubber is attached to a desired position inside a mold, and when a concrete is poured into the mold, a hollow projecting portion provided at a tip of the mold body is provided. A step of forming a mounting hole in a concrete molded product by injecting a pressurized fluid and inflating the projecting portion into a desired shape; and after pouring concrete, a desired amount of the pressurized fluid flows out of the projecting portion. Curing and solidifying the concrete molded product in a reduced pressure state, and releasing the protruding portion from the mounting hole by releasing the pressurized fluid from the protruding portion and depressing the protruding portion at the time of release from the concrete. Forming a mounting hole in a concrete molded product, comprising the step of releasing the molded product. 2. A concrete by flowing a pressurized fluid through a flow passage into a large-diameter hollow protruding portion formed at the tip of a tapered male mounting base portion mounted in a formwork. At the time of casting, the protrusion is expanded by pressurization to form a mounting hole in the concrete molded product, and at the time of release, the pressurized fluid flows out from the protrusion and the protrusion is shrunken from the tip width of the mounting base. 2. The method for forming a mounting hole in a concrete molded product according to claim 1, wherein the protrusion is pulled out from the mounting hole in the axial direction and released. 3. A male body formed of an elastic material such as rubber and mounted at a desired position in a mold, and a pressurized fluid is formed at the tip of the male body and flows in when concrete is poured in to expand the concrete body. When the concrete is cured or hardened in the concrete molded product, a desired amount of pressurized fluid flows out and the pressure is reduced. A male mold for a concrete molded product, characterized in that: 4. The male main body has a tapered mounting base portion mounted on a mold, and a large diameter formed at the tip of the mounting base portion and capable of expanding and contracting by flowing in or out of a pressurized fluid. And a flow passage through which the pressurized fluid flows in or out, which is formed in the male body and communicates with the inside of the protrusion. 4. A male mold of the concrete molded product according to 3. 5. A position restricting projection is provided on a top of the projecting portion, and the position restricting protrusion is provided so as to coincide with a pulling-out direction of the male mold body when the concrete-formed product is released from the mold. A male mold for the concrete molded product according to claim 3. 6. The protruding portion has an outer shape of any one of a substantially circular cross section, a substantially elliptical cross section, and a substantially triangular cross section, and a hollow portion that can be enlarged or reduced is formed inside the protruding portion. The male molding die for a concrete molded product according to claim 3, wherein 7. The concrete molded product according to claim 3, wherein the pressurized fluid is one of air and gas, or one of water and oil. Male mold.