JPH10121725A - Concrete opening section molding form - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate joint work between a pair of die members, make it possible to carry out the work within a short period of time and, at the same time, to reduce the number of components for molding a grip to enable the molding of the die members efficiently. SOLUTION: One end face of the circumferential wall 18 is opened and, at the same time, a pair of square cylindrical die members 15 and 16 formed by closing the other end face with the bottom wall 17 are provided. A joint projection 19 is projected to the bottom wall 17 of one die member 15, an insertion-hole for inserting the joint projection 19 therein is formed in the other die member 16, and elastic members 21 are fitted into the joint projections 19 in a state to insert the joint projections 19 into the insertion-holes to make it possible to joint both die members 15 and 16. A bearing pate 27 is mounted to one die member 15, slide metal fixtures 30 can be vertically slid to the bearing plate 27, and they are interlocked with concrete forms 11. An opening section 14 is molded in a concrete wall 12 between the concrete forms 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete opening forming form used for forming an opening such as a ventilation hole in a concrete wall such as a cloth foundation concrete for a house.

[0002]

2. Description of the Related Art A conventional opening-forming mold of this type is provided with a pair of square cylindrical mold members having both ends opened, and the peripheral wall of the mold member gradually increases from one end to the other end. A tapered portion that increases in diameter is formed. A male screw is joined to the bottom wall surface of one mold member, and an insertion hole for inserting the male screw is formed in the other mold member.By screwing a thumbscrew with the male screw inserted into the insertion hole Both mold members are connected by a bottom wall.

[0003] A handle for attaching and releasing the mold members is attached to the bottom wall surfaces of both mold members separately from the mold members. Further, one of the mold members is provided with a support plate for suspending and holding the mold member on the concrete formwork, and the support plate has a pair of slide fittings for adjusting the vertical position of the mold member to slide up and down. A long hole is provided. A bolt is attached to the slide fitting and a thumb screw is tightened through a long hole of the support plate, so that the position at which the slide fitting is supported on the concrete form can be adjusted.

[0004] After the vertical position of the mold member is adjusted by a support plate and a slide bracket, the two mold members are connected and fixed and interposed at a predetermined position between the concrete molds. In this state, when concrete is poured between the concrete forms, an opening is formed in the concrete by the mold member.

[0005]

However, the conventional opening forming mold has the following various problems. (1) When connecting a pair of mold members, a plurality of male screws joined to one mold member must be inserted into the insertion holes of the other mold member, and then a thumb screw is screwed into each male screw and tightened in order. No. For this reason, there has been a problem that such connecting work of the mold members is troublesome and time-consuming. (2) The handles for attaching and releasing the mold members provided on the bottom wall surfaces of both mold members are formed of members separate from the mold members. For this reason, there is a problem that the number of parts increases and it takes time to form the mold member. (3) Further, the slide fitting for adjusting the vertical position of the mold member moves up and down along a pair of long holes provided in the support plate, and a thumb screw is tightened to a bolt provided on the slide fitting at a predetermined position. It is supposed to be. For this reason, in order to hold the slide fitting in a horizontal position, the vertical position of the slide fitting with respect to the pair of long holes must be confirmed and determined, and there has been a problem that such positioning is not easy.

The present invention has been made by paying attention to such problems existing in the conventional technology. An object of the present invention is to provide a concrete opening forming mold that can easily connect a pair of mold members and can be performed in a short time.

[0007] Another object of the present invention is as follows.
An object of the present invention is to provide a concrete opening forming frame capable of efficiently forming a mold member by reducing the number of parts for a handle.

It is still another object of the present invention to provide a concrete opening forming mold capable of easily and accurately setting the vertical position of a metal fitting for positioning a mold member. It is in.

[0009]

In order to achieve the above object, a concrete opening forming mold according to the first aspect of the present invention is provided with a concrete interposed between opposing concrete forms. In an opening forming mold for forming an opening in concrete formed by being cast between molds, a pair of bottomed cylindrical mold members are provided, and a peripheral wall of each mold member faces the opening side. A tapered portion for increasing the diameter is formed, and a connection projection protruding toward the other mold member is formed on the bottom wall of one mold member, and the connection protrusion is inserted into the bottom wall of the other mold member. And an insertion hole for fitting the two mold members into an elastic member for connecting and fixing the two mold members, and the two mold members are interposed and arranged between the concrete forms while being connected and fixed to each other on the bottom wall. .

According to a second aspect of the present invention, in the concrete opening forming mold according to the first aspect, the one mold member is provided with a support plate for engaging and holding the concrete mold. The support plate supports a slide bracket for adjusting the position to be locked and held on the concrete formwork. On both sides of the slide bracket, both sides of the support plate are engaged so that the slide bracket is fixed to the support plate. An engagement portion for sliding up and down while maintaining substantially horizontal is formed by bending.

According to a third aspect of the present invention, in the mold for forming an opening of concrete according to the first or second aspect, the bottom wall of each of the two mold members is provided with a mold member at the time of installation or release. It is formed by bending a handle for gripping.

Therefore, when an opening is formed in concrete using the concrete opening forming mold according to the first aspect, the bottom wall of one mold member and the bottom wall of the other mold member are formed. Are joined, the connecting protrusion of one mold member is inserted through the insertion portion of the other mold member, and then the connecting protrusion is fitted to the elastic member. In this state, when concrete is poured between the concrete forms, an opening is formed in the concrete by both mold members.

When releasing the mold member in a state where the concrete has hardened to a predetermined hardness, after releasing the concrete form from both sides of the concrete, the elastic member is removed from the connection projection. Release the connection between the two mold members.
In this state, each mold member is pressed and moved in the direction of removing the mold.
Thereby, both mold members can be released from both sides of the concrete opening.

As described above, since the connection between the two mold members is performed by the engagement between the connection projections and the elastic members, the work of connecting and releasing the mold members can be performed quickly. In one embodiment, a support plate is provided on one of the mold members for locking and holding the concrete formwork, and the support plate is locked with the concrete formwork. In addition to supporting the slide fitting for adjusting the holding position, engaging portions for engaging both sides of the support plate are formed on both sides of the slide fitting.

For this reason, when the two mold members are locked and held at a predetermined position with respect to the concrete formwork, when the slide metal is slid up and down with respect to the support plate, the engaging portions on both sides of the slide metal are supported by the support plate. By engaging on both sides of
The sliding of the slide fitting can be performed in a state where it is kept substantially horizontal, and the work of arranging the mold members can be performed easily and accurately.

[0016] In the concrete opening forming frame according to the third aspect, a handle for gripping the mold member at the time of installation or release is bent on the bottom wall of both mold members. Therefore, there is no need to attach another member to form a handle, and the handle can be formed only by bending a part of the bottom wall, so that the molding of the mold member can be performed efficiently.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.

As shown in FIG. 1 and FIG. 2, concrete forms 11 are opposed to each other at a predetermined interval, and concrete is cast between the concrete forms 11 to form a concrete wall 12 such as a foundation concrete. Is formed. The opening forming frame 13 is interposed between the concrete forming frames 11, and an opening 14 such as a ventilation hole is formed in the concrete wall 12 by the opening forming frame 13.

As shown in FIGS. 2 to 7, the opening forming mold 13 is constituted by a pair of mold members 15 and 16. Each of the mold members 15 and 16 is formed in a rectangular tube shape of metal so as to have substantially the same shape, and one end is opened and the other end is closed by a bottom wall 17. The peripheral wall 18 is formed so as to increase in diameter from the bottom wall 17 side to the opening end side.

A plurality of (four in this embodiment) connecting projections 19 are provided on the bottom wall 17 of the one mold member 15 at predetermined intervals. Plurality (4 in this embodiment)
) So that the insertion holes 20 correspond to the connection projections 19,
It is formed on the bottom wall 17 of the other mold member 16 at predetermined intervals. Then, the connection projection 19 of the one mold member 15 is formed.
Is inserted into the insertion hole 20 of the facing mold member 16, and an elastic member 21 made of synthetic rubber is fitted to the tip of the insertion member 20, whereby the two mold members 15 and 16 are joined to each other on the bottom wall 17.

At this time, the bottom wall 1 of both mold members 15 and 16
The metal support frame 2 having a square plate shape shown in FIG.
2 is interposed. Bent part 24
Are formed by bending both upper and lower edges of the support frame 22 to reinforce the support frame 22,
When the base members 16 are joined to the bottom wall 17, the wire mesh 23 can be reliably supported between the two mold members 15, 16.

The contact surface 25 is formed with a predetermined width around the opening end of each of the mold members 15 and 16.
6, the contact surfaces 25 of the two mold members 15, 16 are in contact with the concrete form 11 when the mold members 15, 16 are connected, so that concrete does not enter the mold members 15, 16.

The handle 26 is provided on the bottom wall 1 of each of the mold members 15 and 16.
7 is formed by cutting and raising a central portion in a rectangular shape and bending a part of the cut and raised portion. And
When the mold members 15 and 16 are attached to the concrete formwork 11 or when the mold members 15 and 16 are released after the concrete is cast, the work can be performed by hanging the handle 26.

The concrete members 11 and 16 are
The support plate 27 is joined to the outer surface of the peripheral wall 18 of one of the mold members 15 so as to extend along the concrete form 11. The support plate 27 is formed integrally at a joint portion of the mold member 15 with the peripheral wall 18, but is formed in two parts with a predetermined space at the center in a portion above the contact surface 25 of the mold member 15. . The pair of long holes 28 are formed to extend vertically on both sides of the support plate 27. The bending piece 29 for reinforcement is formed by bending the upper edge of the support plate 27 inward, and reinforces the support plate 27.

As shown in FIG. 8, the slide fitting 30 has an L-shaped cross section, and a vertical plate 31 has a pair of rectangular support holes 32 formed therethrough. The pair of positioning bolts 33 project from the inside of the vertical plate 31 through the long holes 28 and the support holes 32 of the slide fitting 30, and the wing nuts 34 are tightened from the outside.

Then, with the wing nut 34 loosened, the slide fitting 30 can slide with respect to the support plate 27,
The slide fitting 30 is positioned and fixed to the support plate 27 with the wing nut 34 tightened at a predetermined position. The engaging portions 35 are bent at upper portions on both sides of the slide fitting 30 and are engaged with both sides of the support plate 27 so that the slide fitting 30 is substantially horizontal with respect to the support plate 27 as shown by a two-dot chain line in FIG. It is possible to move up and down while maintaining.

The horizontal plate 36 of the slide fitting 30 is placed on the upper surface of the concrete form 11.
When a wooden form or the like is used for the nail hole 38 of the horizontal plate 36 of the slide fitting 30, the horizontal plate 36 is placed on the wooden form, and a nail is driven into the nail hole 38 to insert the slide fitting. 30 can be fixed to a wooden formwork.

Next, the operation of the concrete opening forming frame constructed as described above will be described. Now,
When forming the opening 14 in the concrete wall 12 using the opening forming mold 13, as shown in FIG. 2, the mold member 15 having the support plate 27 and the support member 27 are not provided. Mold member 16 and wire mesh 23 held by support frame 22
And prepare. Then, the bottom wall 1 of both mold members 15, 16
7 are opposed to each other, and a wire mesh 23 is arranged between the two mold members 15 and 16 to couple the two mold members 15 and 16 together.

That is, the plurality of connecting projections 19 formed on one mold member 15 are inserted through the wire mesh 23 into the insertion holes 20 of the other mold member 16. At this time, work is performed by putting a hand on a handle 26 provided on the bottom wall 17 of the two mold members 15 and 16. Then, by fitting the elastic member 21 into the connecting projection 19 protruding from the insertion hole 20 of the other mold member 16, the two mold members 15, 16 are connected and fixed with the wire mesh 23 interposed on the bottom wall 17. . At this time, the four connection projections 19 are tightened by the tightening force of the rubber of the elastic member 21, and the two mold members 15 and 16 are connected by the required tightening force. This operation can be performed easily and quickly because it is only necessary to fit the elastic member 21 into the connecting projection 19.

Next, the pair of wing nuts 34 of the slide fitting 30 slidably attached to the one mold member 15 are loosened, and the slide fitting 30 is moved up and down in accordance with the mounting position with respect to the concrete formwork 11 to position. Then, the wing nut 34 is tightened at that position. At this time, the engagement portions 35 are provided on both upper sides of the slide fitting 30 and the slide fitting 30 moves in a substantially horizontal state, so that the positioning of the slide fitting 30 can be easily performed.

Thereafter, as shown in FIG.
5 and 16 are inserted between the concrete forms 11, and the horizontal plate 36 of the slide fitting 30 is locked and supported on the upper end surface of one concrete form 11. As a result, the two mold members 15 and 16 are interposed between the concrete forms 11, and the contact surfaces 25 of the peripheral walls 18 are in close contact with the inner surfaces of the concrete forms 11.

When concrete is poured between the concrete forms 11 in this state, a concrete wall 12 such as a foundation concrete is formed by the concrete form 11 and the concrete walls 12 are formed in the concrete wall 12 by both mold members 15 and 16. An opening 14 such as a ventilation hole is formed. At this time, since the wire mesh 23 is interposed between the bottom walls 17 of the two mold members 15 and 16, the wire mesh 23 is stretched integrally in the opening 14.

When the mold members 15 and 16 are released from the mold with the concrete wall 12 solidified to a predetermined hardness, the concrete form 11 is released from both sides of the concrete wall 12. Thereafter, the pair of wing nuts 34 of the slide fitting 30 attached to the one mold member 15 are loosened, and the elastic member 21 is removed from the connection projection 19.

In this state, the user grips a handle 26 provided on the bottom wall 17 of each mold member 15 and pulls each mold member 15 in a direction away from the concrete wall 12. Thereby, the both mold members 15 and 16 can be released from both sides from the opening 14 of the concrete wall 12.

The effects exerted by the first embodiment will be described below. (1) A connecting projection 19 is provided on the bottom wall 17 of one mold member 15 and an insertion hole 20 is provided on the other mold member 16 so that the connection projection 19 is inserted through the insertion hole 20. Then, the elastic member 21 is fitted to the connecting projection 19 protruding from the insertion hole 20.

Therefore, the work of connecting the pair of mold members 15 and 16 and the work of releasing the concrete after casting are easy, and the work can be performed in a short time. (2) The handle 26 cuts and raises the bottom wall 17 of both the mold members 15 and 16, instead of attaching the member separate from the bottom wall 17 of the mold members 15 and 16 to the bottom wall 17. It is formed by bending.

Accordingly, the number of parts for forming the handle can be reduced, and the molding of the mold member can be performed efficiently. (3) A slide fitting 30 is provided on a support plate 27 formed on one mold member 15 so as to be vertically movable, and engagement portions 35 are engaged with both sides of the support plate 27 at upper portions on both sides thereof.

Therefore, the vertical position of the slide fitting 30 for positioning the mold members 15 and 16 with respect to the concrete mold 11 can be easily and accurately adjusted. (4) As described above, the connection protrusion 19 and the elastic member 21
The pair of mold members 15 and 16 are connected to each other, and the vertical position of the mold members 15 and 16 is adjusted by the slide fitting 30 having the engagement portion 35.

Therefore, the two mold members 15 and 16 can be easily and quickly interposed between the concrete molds 11. (5) In this opening forming mold, the opening 14 is formed in the concrete wall 12 by the two mold members 15 and 16.
Is molded.

For this reason, the opening area at one end of the opening 14 is extremely small due to the tapered portions of the peripheral walls 18 of the mold members 15 and 16 as compared with the case where the opening is formed using one mold member. In addition, the opening 14 having a large opening area can be secured. (6) The pair of mold members 15 and 16 are formed to have the same shape except for the support plate 27.

Accordingly, the two mold members 15 and 16 can be manufactured as a common part, and the manufacturing can be facilitated and the manufacturing cost can be reduced. (7) Since the connecting projection 19 is formed to have a diameter of about 3 mm (usually 6 mm or less), it is possible to prevent the wire mesh 23 from being damaged when the wire mesh 23 is inserted. (Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. In this embodiment, points different from the first embodiment will be mainly described.

As shown in FIG. 11, the auxiliary mold member 39 is formed in a rectangular frame shape, and is formed larger than the mold members 15 and 16 including the depth. The auxiliary mold member 39 has a peripheral wall 40 formed in a tapered shape like the peripheral wall 18 of the mold members 15 and 16, and the mold member 16 is accommodated inside. The bent reinforcing plate 41 is used as the auxiliary member 39.
And the strength of the auxiliary mold member 39 is maintained.

As shown in FIG. 10, the auxiliary mold member 39 is put on the mold member 16, and one of the mold members 15 is connected to the concrete form 11 via the wire mesh 23, thereby supporting the first embodiment. The concrete wall 12 wider than the form can be formed.

Now, as shown in FIG.
9 is placed on the mold member 16 and the wire mesh 2 is attached to the auxiliary mold member 39.
3 is pressed, and the bottom wall 17 of one of the mold members 15 is pressed against the wire mesh 23. At this time, one mold member 1
5 is connected to the other mold member 1 via a wire mesh 23.
6, the elastic member 21 is fitted to the connecting projection 19 protruding from the insertion hole 20, and the two-type members 15,
16 are connected.

According to the second embodiment, the auxiliary mold member 3
By arranging 9 between the two mold members 15, 16, the width of the concrete wall 12 to be formed can be easily increased.

The present invention can be embodied with the following modifications. (A) The engaging portion 35 of the slide fitting 30 is supported by the support plate 2.
7 to form a U-shaped cross section so as to enclose the side edge.

In this manner, when the wing nut 34 is loosened, the slide fitting 30 can be prevented from dropping off the support plate 27. (B) In the first embodiment or the second embodiment,
An insertion hole 20 is provided in one mold member 15, and the connection projection 19 is provided.
Is provided on the other mold member 16. (C) In the first embodiment or the second embodiment,
The support plate 27 provided with the slide fitting 30 is connected to the other mold member 1.
6 or on both mold members 15 and 16. (D) The mold members 15, 16 are made of a synthetic resin having good impact resistance and weather resistance such as ABS resin or polypropylene resin.

In this case, the mold members 15 and 16 can be easily formed, and the manufacturing cost can be reduced. (E) The length, width, and depth of each of the mold members 15 and 16 may be changed, or the mold members 15 and 16 may be formed in a cylindrical shape, an elliptical shape, or a rectangular shape such as a hexagonal shape.

In this way, the opening 14 having a desired size or shape can be formed in the concrete wall 12. (F) The handle 26 is formed by cutting and raising the bottom surface 17 of the mold members 15, 16 in the lateral direction, or by forming each of the mold members 15, 16.
Or one pair at a time. (G) The elastic member 21 is formed of a thermoplastic elastomer such as a polyurethane elastomer. (H) The mold for forming an opening of the present invention is used for forming an opening different from the ventilation hole of the embodiment. (I) As shown in FIG. 12, the insertion holes 20 of the respective mold members 15 and 16 are formed by burring tapping on the bottom wall 17, and the insertion holes 20 are formed at the ends of the connection projections 19. Forming a screw portion to be screwed into the portion and forming a flange portion; In addition, the connection protrusion 1
The body side having 9 sharp portions is formed thinner than the screw portion 42 (for example, the screw portion 42 has a diameter of 4 mm and the body has a diameter of 3 mm).
mm), so that the insertion hole 20 of the mold member 16 can be easily inserted. The burring tapping is a process in which a hole flange is formed on a flat plate so that screws can be screwed together.

With this configuration, the two mold members 15, 1
6, the same insertion hole 20 may be formed in the bottom wall 17 and the screw portion 42 of the connection projection 19 may be screwed into a portion of the one mold member 15 where the insertion hole 20 is formed. Can be formed. Moreover, the screwing portion 42 of the connecting projection 19 is screwed away from the portion forming the insertion hole 20 of the mold member 15, so that the connecting projection 19 can be removed from the bottom wall 17 of the mold member 15. Therefore, when the connecting projection 19 is bent or broken, the connecting projection 19 can be easily replaced. (J) The support plate 27 is formed of a single plate without being divided into two, and the structure is simplified to facilitate manufacture.

Further, the technical idea grasped from the above embodiment will be described below. (1) The concrete opening forming mold according to claim 1, wherein a plurality of the connecting projections are provided on a bottom wall of one of the mold members, and the elastic member is formed of synthetic rubber.

In the case of such a configuration, the connection between the two mold members can be reliably performed, and the connection operation can be easily performed. (2) The slide fitting is formed in an L-shaped cross section composed of a vertical plate and a horizontal plate, the vertical plate can be moved along the support plate, and the horizontal plate can be positioned on the concrete formwork. 3. The concrete opening forming mold according to claim 2, wherein at least a part of both sides of the plate is bent to the rear side to form an engaging portion.

With such a configuration, the slide fitting can be moved up and down while being kept horizontal, and can be easily positioned and fixed on the concrete formwork by the horizontal plate. (3) The concrete opening forming mold according to claim 3, wherein the handle is formed by cutting and raising a bottom wall of the mold member and further bending a part of the cut and raised portion.

With this configuration, the handle can be easily formed integrally from the bottom wall of the mold member. (4) The concrete opening forming mold according to any one of claims 1 to 3, wherein a wire mesh can be arranged between the bottom walls of the both mold members.

With this configuration, a wire net can be arranged in the opening at the same time as the opening is formed. (5) The concrete opening forming mold according to any one of claims 1 to 3, wherein the tapered portion is provided on a part of the peripheral wall of each mold member.

With this configuration, the opening can be formed wider. (6) The concrete opening forming frame according to (4), wherein the connection projection is formed so as to be thin so as not to damage the wire mesh when the wire mesh is inserted.

With this configuration, both mold members can be connected while easily preventing damage to the wire mesh. (7) Burr tapping is performed on the bottom wall of the two mold members to form an insertion hole, and a threaded portion is provided at one end of the connecting projection, and the threaded portion is formed into an insertion hole for the one mold member. The concrete form for forming an opening of concrete according to claim 1, wherein the form is formed so as to be screwable and retreatable at a portion to be screwed.

With such a configuration, when the connecting projection is bent or broken, the connecting projection can be easily replaced, and the same processing is performed on the bottom walls of both mold members so that the insertion hole is formed. Can be formed.

[0059]

The present invention is configured as described above, and has the following effects. According to the concrete mold for forming an opening of concrete according to the first aspect of the present invention, the work of connecting a pair of mold members and the work of releasing the mold members after concrete casting are easy, and the work can be performed in a short time. Can be done.

According to the mold for forming an opening of concrete according to the second aspect of the present invention, in addition to the effect of the first aspect, the number of parts for forming the handle is reduced, and Molding can be performed efficiently.

According to the third aspect of the present invention, in addition to the effects of the first and second aspects of the present invention, a sliding metal fitting for positioning a mold member is provided. The vertical position can be set easily and accurately.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a use state of an opening forming mold according to a first embodiment.

FIG. 2 is an exploded perspective view showing an opening forming mold and a wire mesh.

FIG. 3 is a front view of a state where one of the mold members is assembled via a wire mesh.

FIG. 4 is a plan view of FIG. 3;

FIG. 5 is a front view showing the other mold member.

FIG. 6 is a plan view of FIG. 5;

FIG. 7 is a side view of FIG. 5;

FIG. 8 is a perspective view showing a slide fitting.

FIG. 9 is a perspective view showing a state where a wire net is attached to a support frame.

FIG. 10 is a cross-sectional view showing a use state of the opening forming mold of the second embodiment.

FIG. 11 is a perspective view showing a reinforcing member.

FIG. 12 is a cross-sectional view showing another example of the insertion hole in the bottom wall of the connecting member and the mold member.

[Explanation of symbols]

11 ... concrete formwork, 12 ... concrete wall, 13
... Opening forming mold, 14 ... Opening, 15, 16 ... Mold member, 17 ... Bottom wall, 18 ... Peripheral wall, 19 ... Connection projection, 2
0 ... insertion hole, 26 ... handle, 27 ... support plate, 30 ... slide fitting, 35 ... engagement part.

Claims (3)

[Claims] 1. A concrete opening forming mold for forming an opening in concrete formed between concrete forms by being interposed between opposing concrete forms, wherein a pair of bottomed bottoms is provided. A connecting member having a cylindrical mold member, a tapered portion having a diameter increasing toward an opening formed on a peripheral wall of each mold member, and a connecting projection projecting toward the other mold member on a bottom wall of one mold member; The bottom wall of the other mold member is provided with an insertion hole through which the connecting projection is inserted to fit into an elastic member that connects and fixes the two mold members, and the two mold members are mutually connected at the bottom wall. A concrete opening forming mold that is interposed and placed between concrete forms while being connected and fixed. 2. The one mold member is provided with a support plate for locking and holding to the concrete formwork, and the support plate is provided with a slide fitting for adjusting a position for locking and holding to the concrete formwork. Claims: An engaging portion for supporting and sliding on both sides of a slide fitting is formed to be engaged with both sides of a support plate to slide up and down while the slide fitting is maintained substantially horizontal with respect to the support plate. 2. The mold for forming an opening of concrete according to 1. 3. The mold for forming an opening of concrete according to claim 1, wherein a handle for gripping the mold member at the time of installation or release is bent on a bottom wall of the both mold members. frame.