JP2952181B2 - Concrete formwork connector - Google Patents

Abstract

A concrete molding form member connector comprises a first holding portion (3) having a linearly extending first holding surface (3a) of a prescribed length, a cylindrical insertional shaft portion (2), having a central axis being perpendicular to the first holding surface (3a), which is provided in the vicinity of a first end of the first holding surface (3a), and a second holding portion (4), having a second holding surface (4a) being opposed to the first holding surface (3a) in a parallel manner at a prescribed space in a region close to a second end of the first holding surface (3a), which is continuous with the first holding portion (3) on the second end of the first holding surface (3a) so that its free end is positioned at a prescribed space with respect to the insertional shaft portion (3). The insertional shaft portion (2) is inserted in through holes which are provided in overlapping side plate portions of adjacent form members so that the connector is rotated about the same, whereby the side plate portions of the adjacent form members are held between the first holding surface (3a) and the second holding surface (4a). Consequently, a lightweight concrete molding form member connector having excellent workability, which can be provided at a relatively low cost, is provided. <IMAGE>

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete formwork connector for use in concrete molding and the manufacture of secondary concrete products in civil engineering and construction work.

[0002]

2. Description of the Related Art Conventionally, in order to assemble a concrete form material by connecting a concrete form material in civil engineering construction work or a form material in manufacturing a secondary concrete product, a metal round bar is processed. Tools are used.

[0003] Hereinafter, a conventional concrete formwork connector will be described with reference to Figs. First, referring to FIGS. 8 (a) to 8 (c), a conventional concrete formwork connector 10 includes a one-side holding portion 11;
The other side holding portion 12 which faces the one side holding portion 11 in parallel at a predetermined interval, and a curved portion which is continuous with one end of each of the one side holding portion 11 and the other side holding portion 12 and integrally connects the two. And the insertion shaft 13 extending perpendicularly from the other end of the one-side holding portion 11. Such a concrete molding frame connecting device 10
Is obtained, for example, by bending a metal round bar material such as iron.

[0004] In order to connect and fix the adjacent frame material side plates 5, 6 by using the concrete molding frame material connector 10 having the above-described structure, first, the posture shown in FIG. Then, the insertion shaft portion 13 is inserted into the connecting member mounting hole 27 provided in the form material side plate portions 5 and 6 from the lateral direction. Next, the gripper 16
The one side holding portion 11 and the other side holding portion 12 are rotated around the center of the insertion shaft portion 13 by, for example, hitting with a hammer, and the one side holding portion 11 and the other side holding portion 12 are rotated as shown in FIGS. 9B and 9C. Form material side plate portions 5, 6 between 11 and the other side holding portion 12.
In between.

[0005] The strength of the joint required to fasten the form material side plates 5, 6 is determined by an experiment on a form material connector of a conventional typical wooden concrete molding form, as shown in FIG.
The following description is based on (a) and (b).

Referring to FIG. 10 (a), adjacent form members 17, constituting a wooden concrete forming form,
Form material side plates 5 and 6 are fixed to 18 respectively, and the form materials 17 and 18 are
A pressure P is applied by the driven concrete. Due to the pressure P, a force F0 acts in a direction in which the connecting and fixing of the form members 17 and 18 are separated.

[0007] In order to determine the strength of the fastening portion necessary for connecting and fixing the form members 17 and 18, the following experiment was first performed. Assuming that the lengths L1 and L2 of the form material side plate portions 5 and 6 are 30 mm and 50 mm, respectively, and the length of the form material side plate portions 5 and 6 in the longitudinal direction (perpendicular to the drawing) is 300 mm. As shown in FIG. 10 (a), four nails 19a, 1 having a length of 65 mm and a diameter of 3.5 mm are provided on the side plates 5, 6, respectively.
9b, 19c and 19d, and in this state, FIG.
A tensile test as shown in (b) was performed. as a result,
The force F1 required to break the fastening portion and separate the two frame members 17, 18 was about 150 kg. From this, it is presumed that the force that can be endured per nail in fastening is about 40 kg at the maximum.

In an experiment in which concrete was actually driven, only two nails 19a and 19b shown in FIG. 10 (a) were hit and sufficient strength for connecting and fixing the form material side plates 5, 6 was achieved. Was able to maintain. Therefore, from the experimental results, it is sufficient from the experimental results that the connection between the form members 17 and 18 can withstand a tensile force of about 80 kg, which is a force that can be endured by two nails of 40 kg per one. You can see that. As described above, the strength in the tensile direction for fastening and fixing the formwork connector may be relatively low because the force received by the formwork due to the pressure of the concrete that has been driven is mainly the concrete casting surface of the formwork. This is considered to be due to the fact that it works in the direction perpendicular to the surface and does not work much in that direction.

On the other hand, as shown in FIG. 11 (a), when the metal mold members 17, 18 are fastened and joined by using the above-mentioned conventional metal mold joint member 10 for concrete molding, tension is applied. The force (F2 shown in FIG. 11B) is 180 kg
Then, as shown in FIG. 11B, the side plate portion 5 was deformed and damaged. From this, it was found that the formwork connector 10 can withstand a tensile force of at least 180 kg or more. This value is more than twice as high as the tensile strength of 80 kg when the wooden form members 17 and 18 are connected and fixed to the form material side plate portions 25 and 26 by the two nails 19a and 19b. I can say. That is, since the above-mentioned conventional frame material connector 10 is formed of metal such as iron, it has an excessive strength.

[0010] Such a conventional metal mold material connecting device 1
Since 0 is formed by bending a round bar material,
The contact portions 14, 15 of the one-side holding portion 11 and the other-side holding portion 12 which actually hold the form material side plates 5, 6 are substantially in line contact with each other as shown in FIG. Or, in extreme cases, it is close to point contact. FIG. 12 (b) shows a state in which the frame material side plate portions 5, 6 are sandwiched between the one-side holding portion 11 and the other-side holding portion 12, and the mold is cut along the line AA in FIG. 12 (a). Frame materials 7, 8
2 is a schematic enlarged view of the vicinity of the holding portion in a state where the side walls 5 and 6 of the form material are held. As shown by hatching in FIG. 12B, the portions where the one-side holding portion 11 and the other-side holding portion 12 come into contact with the frame material side plate portions 5 and 6 respectively constitute the frame material connector 10. The contact angle θ is about 15 ° out of 360 ° around the central axis of the rod to be formed. Further, the length of the portion where the one-side holding portion 11 and the other-side holding portion 12 contact the form material side plate portions 5 and 6 in the direction perpendicular to the paper surface of FIG. Assuming that the diameter of the constituting bar is 13 mm, the contact portions 14, 15
Are respectively 20 mm × π × 13 × 15 ° / 360 ° = 34 mm ² . Since the contact area at the holding portion is reduced in this way, when a tensile force is applied to the connecting member of the formwork,
The stress applied to the contact surface of the formwork connector increases,
Therefore, the required strength increases.

[0011]

Since the conventional concrete-forming mold material connecting member is made of a rod material such as iron as described above, the workability is poor due to its large weight, and the concrete When attaching or detaching the molding-form connecting member 10 to or from the forming-material side plate portions 5, 6, the use of a hammer or the like is indispensable because the rigidity of the forming-form connecting member 10 is high. , Detachment from the connector mounting hole provided in the form material side plate, or deformation, or
There was a danger to workers. In addition, there is a problem that rust is generated due to rain or the like to cause corrosion, and because the weight is relatively heavy, it is inconvenient to transport and the work efficiency is poor, and the price is relatively high.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and can be easily and safely attached to or removed from the side walls 5 and 6 of the form material. It is an object of the present invention to provide a concrete formwork connector for concrete molding which can improve work efficiency, prevent corrosion due to rust and the like, does not cause deformation, can withstand long-term use, and is relatively inexpensive.

[0013]

According to a first aspect of the present invention, there is provided a concrete formwork connecting member having a predetermined length extending in a strip shape and having a one-side holding surface. And one-side clamping surface in the area of this one- side clamping surface
With a central axis perpendicular to
A cylindrical insertion shaft portion and a second holding surface facing the other holding surface in parallel in the area near the other end of the one holding surface at a predetermined interval, and the other end of the one holding surface. And a second holding portion which is continuous with the one holding portion and has a free end located at a predetermined distance from the insertion shaft portion, and the one holding surface and the other holding surface are made of concrete.
By making surface contact with the molding form material, concrete
Hold the molding material.

According to a second aspect of the present invention, there is provided a concrete formwork connector according to the first aspect of the present invention, wherein the one-side holding portion and the other-side holding portion are made of a resin molded body.

According to a third aspect of the present invention, there is provided a concrete formwork connector according to the first or second aspect of the present invention, wherein a male screw portion is provided on a free end side of the insertion shaft portion.

[0016]

According to the first aspect of the present invention, there is provided a concrete formwork linking device according to the present invention, in use of which a hole is formed through a side plate portion of an adjacent concrete formwork which abuts against each other. By inserting the insertion shaft into the insertion shaft and rotating the insertion shaft around the insertion shaft, the side plate portions of the adjacent mold members are sandwiched by the one-side clamping surface and the other-side clamping surface. Are connected and fixed.

According to the concrete formwork connector of the present invention, the one-side holding surface and the other-side holding surface come into contact with the side surfaces of the mutually overlapping side plate portions of the adjacent formwork members. The side plate of the form material is clamped by the contact.

According to a second aspect of the present invention, at least one of the holding portions and the other holding portion are formed by integral molding of a resin, and the remaining portion is formed of another material. It is manufactured by appropriately joining and fixing the above-mentioned portions.

According to the concrete formwork connecting member of the third aspect of the present invention, since the male screw portion is provided on the free end side of the insertion shaft portion, it can be used in a state used for connecting the formwork member. Then, a nut is screwed into the male screw portion, and the side surfaces of the side plate portions overlapping each other of the adjacent formwork material are made to have one side holding surface even around the connector mounting hole of the side plate portion in which the insertion shaft portion is inserted. It is clamped and fixed with bolts.

[0020]

An embodiment of the present invention will be described below with reference to the drawings. First, a first embodiment of a concrete formwork connector according to the present invention will be described with reference to FIGS. 1 to 3 as follows. FIG.
Referring to (a) to (c), near one end of the one-side holding portion 3 having the one-side holding surface 3a of a predetermined length extending in a belt shape near one end of the one-side holding surface 3a, the one-side holding surface 3a is provided. In the area
Is provided with a columnar insertion shaft portion 5 having a central axis perpendicular to the one side holding surface 3a . In the vicinity of the other end of the one-side holding portion 3, the other-side holding portion 4 is provided at a predetermined distance from the one-side holding surface 3a and has a free end with which the other-side holding surface 4a faces in parallel. The entirety of the formwork connector 1 of this embodiment is formed by integral molding of resin.

In the case of assembling a concrete molding form for civil engineering work, for example, using the concrete molding form connecting member 1 of this embodiment having such a structure,
When connecting and fixing the form material side plates 5, 6, FIG.
As shown in (2), the insertion shaft portion 2 is inserted into the connecting member mounting hole 27 provided in the form material side plate portions 5, 6. Next, FIG.
As shown in FIG. 2B, it is manually rotated about the insertion shaft portion 2 and is moved between the one-side holding portion 3 and the other-side holding portion 4, that is, the one-side holding surface 3a and the other-side holding surface facing each other. The overlapping frame material side plate portions 5, 6 are sandwiched between 4a.

In the present embodiment, the form members 7,
A tensile test was performed to determine the strength with respect to the force in the tensile direction exerted on No. 8. As a result, as shown in FIG. 5 (b), the form member connecting tool 1 breaks from the state shown in FIG. 5 (a) at the connecting portion between the one-side holding portion 3 and the other-side holding portion 4. The force F3 in the tensile direction required about 100 kg, that is, the form member connecting device 1 of the present embodiment did not break until the force F3 in the tensile direction applied to the form members 7 and 8 was about 100 kg. Considering that the required strength in the tensile direction required when used for assembling a mold for concrete molding is about 80 kg as described above, it is understood that the strength is sufficient.

Next, the contact pressure that the one-side holding surface 3a and the other-side holding portion 4a receive from the frame material side plate portions 5 and 6 when using the form material connecting tool 1 of the present embodiment will be considered. The portions of the formwork connector 1 which come into contact with the formwork side plates 5, 6 during use thereof are opposed to the hatched area 3a on the one side and the other side 4a on the other side. Area. The area of each of these regions is about 200 mm ² when the length in the longitudinal direction is set to 20 mm and the width is set to 10 mm. This is the case of the above-described conventional formwork connector 10 (the contact area is about 34 mm ² ).
This means that a contact area approximately six times that of the above is secured.

Since the force in the pulling direction acting on the form material in the use state of the form material connecting tool 1 is at most about 100 kg, the force between the form material connecting tool 1 and the form material side plate portions 5 and 6 can be reduced. The surface stress generated on the contact surface is about 0.5 kg / mm ^2. With such a surface stress, a normal resin molded body can sufficiently withstand the stress.

As described above, the formwork connector 1 of the present embodiment is
Is formed by integral molding of resin material,
It is easy to manufacture and lightweight, and therefore has good workability during transportation and installation. In addition, compared to the conventional frame material connector 10 made of a metal material, the frame material connector 1 of the present embodiment made of a resin material does not have excessive rigidity. Even when the side plate portion is sandwiched for clamping, it is not necessary to hit with a hammer or the like, and it can be manually rotated sufficiently, so that the workability at the time of attachment and removal is further improved.

As the resin material for forming the formwork connector 1 of this embodiment, a mixture of an ABS resin having relatively high mechanical strength and a thermoplastic nylon resin was used. Mixtures with thermoplastic engineering plastics other than resins can also be used. AB
As a mixture with the S resin, a thermoplastic resin material is optimal, but it is also possible to use a thermosetting polyester or epoxy resin as the mixture.

In the form member connecting device 1 of the first embodiment described above, the cross sections of the one side holding portion 3 and the other side holding portion 4 are both rectangular as shown in FIG. 6 (a). Although the case is shown, the cross-sectional shape may be any shape as long as the one-side holding surface 3a and the other-side holding surface 4a can form a flat surface, and if the required mechanical strength is satisfied, for example, as shown in FIG. It is also possible to adopt a cross-sectional shape as shown in (b) to (d). Particularly, the cross-sectional shape as shown in FIG. 6B or FIG. 6D has a rib structure,
It is possible to further reduce the weight while maintaining the mechanical strength, and to hold the form material side plate portions 5 and 6 based on the same principle as that in the case of FIG. .

Next, a concrete formwork connector 30 according to a second embodiment of the present invention will be described with reference to FIGS. Formwork connector 30 of the present embodiment
In, the insertion shaft portion 2 is formed by processing metal in advance,
When the one-side holding portion 3 and the other-side holding portion 4 are integrally formed of resin, the base ends of the one-side holding portion 3 are joined to the one-side holding surface 3a near the free end of the one-side holding portion 3, and FIG. )
Is integrally formed into the shape shown in FIG. As shown in FIG. 4A, a male screw portion 2a is formed on the free end side of the insertion shaft portion 2 of the formwork connector 30 of the present embodiment.
As shown in FIG. 4 (b), a nut 2b is screwed to hold the frame material side plates 5, 6, and the one side holding surface 3
Formwork side plate portions 5 and 6 are strongly clamped between the vicinity of male screw portion 2a and the pressing surface of nut 2b opposed thereto.
As a result, the frame material side plates 5, 6 are located between the one-side holding portion 3 and the other-side holding portion 4, and between the one-side holding portion 3 and the nut 2b.
And between both. For this reason, more rigid connection and fixing of the form members are realized.

Insertion shaft 2 of formwork connector 30 of this embodiment
As shown in FIG. 7 (a), for example, a sleeve-shaped metal cover 22 can be reinforced by press-fitting the base end to the base end. Further, the insertion shaft portion 2 of this embodiment is provided with the one-side holding portion 3 and the other-side holding portion 4 instead of being buried and formed simultaneously when the one-side holding portion 3 and the other-side holding portion 4 are integrally formed. 7B, a female screw 3b is formed near the free end of the one-side holding portion 3, and a male screw portion 2b provided on the metal insertion shaft portion 2 is screwed into the female screw 3b as shown in FIG. They can be joined and fixed together. Also, on the free end side of the one side holding portion 3,
A cylindrical hole may be formed instead of the female screw 3b, and the base end side of the insertion shaft portion 2 may be press-fitted into the cylindrical hole so as to be joined and fixed.

Also in the formwork connector 30 of the second embodiment, the one-side holding portion 3 and the other-side holding portion 4 which are integrally formed of resin are made of the same resin as in the first embodiment. Materials can be used.

The concrete forming mold connecting members 1 and 30 according to the first and second embodiments of the present invention described above are, for example, shown in FIG. Also effective for assembling a formwork for forming a concrete secondary product such as a large box culvert made of concrete as shown in FIG. 13 (a) and an L-shaped product for standing as shown in FIG. 13 (b). Used for

[0032]

As explained above, according to the concrete formwork connector of the present invention, the side surfaces of the side plates of the adjacent formwork are held on one side and the other side. Since the clamping is performed by surface contact with the clamping surface, the required clamping force is secured with a relatively small clamping pressure, and a stable clamping operation can be performed.

Also, since the required clamping force can be secured with a relatively small clamping pressure, the pivoting around the insertion shaft portion and the clamping of the form material side plate between the one-side clamping surface and the other-side clamping surface are not so necessary. A large frictional force does not act, and the turning operation can be performed manually without hitting with a hammer or the like, thereby improving workability in assembling the form material.

Further, since the required clamping force can be secured with a relatively small clamping pressure by clamping by surface contact, the material of the main part is made of resin as described in claim 2. It can be constituted by a molded body. As a result, the main part is formed by integral molding of the resin, and the remaining part formed of another material can be manufactured by bonding and fixing it appropriately by bonding or the like, so that it is lightweight, has good workability, and is suitable for mass production. Suitable concrete formwork couplers can be provided at relatively low prices.

According to the third aspect of the present invention, the nut is screwed into the male screw portion of the insertion shaft portion to fasten the form material side plate portion, thereby providing a stronger rigidity. The connection and fixing of the form material is realized.

[Brief description of the drawings]

1 (a) is a perspective view of a concrete formwork connector according to a first embodiment of the present invention, FIG. 1 (b) is a front view thereof, and FIG. 1 (c) is a side view thereof.

FIG. 2A is a side view of a state in which the formwork connector shown in FIG. 1 is mounted in a mounting hole provided in a forming formwork side plate;
(B) is a side view of the state in which the form material connector sandwiches the form material side plate, and (c) is a perspective view thereof.

FIG. 3 is a perspective view for explaining a portion where one-side holding portion and the other-side holding portion of the formwork connector shown in FIG. 1 are in contact with a formwork side plate portion;

FIG. 4 (a) is a perspective view of a concrete formwork connecting member according to a second embodiment of the present invention, and FIG. 4 (b) is a state where the formwork connecting member sandwiches a formwork side plate portion. It is a perspective view of.

FIG. 5A is a cross-sectional view of the first embodiment of the present invention, in which the form-material connecting member sandwiches the form-material side plate, and FIG. 5B is a drawing in which a tensile force F3 acts on the form material. FIG. 6 is a cross-sectional view showing a state in which the formwork connector is broken.

FIG. 6 (a) is a view showing a cross-sectional shape of one side holding portion and the other side holding portion in the first embodiment of the present invention;
(B)-(d) is a figure which shows the modification of the cross-sectional shape.

FIG. 7A is a perspective view showing a modification in which the insertion shaft is reinforced by a metal cover in the formwork connector of the second embodiment of the present invention, and FIG. 7B is a perspective view of the insertion shaft; It is a perspective view showing a modification in which a male screw part is also provided on the base end side, and it is screwed and joined to one side holding part.

FIG. 8 (a) is a perspective view of a conventional concrete-forming mold frame connector, FIG. 8 (b) is a front view thereof, and FIG. 8 (c) is a side view thereof.

9 (a) is a side view showing a state where the conventional mold material connecting tool shown in FIG. 8 is attached to a mounting hole provided in the mold material side plate portion,
(B) is a side view of the state which rotated the form material connection tool and pinched the form material side plate part, (c) is the perspective view.

10A is a cross-sectional view showing a state in which a conventional wooden form material side plate is fastened with a nail and the form materials are connected, and FIG. 10B is a drawing in which the form material is subjected to a tensile force. It is sectional drawing of the state which fractured | ruptured the fastening part.

11 (a) is a cross-sectional view of the conventional metal-made concrete formwork connector shown in FIG. 8 sandwiching a formwork side plate, and FIG. 11 (b) is a tensile force applied to the formwork. FIG. 10 is a cross-sectional view showing a state in which the form material is deformed as a result of the action of F2.

FIG. 12A is a perspective view for explaining a region where a conventional concrete forming mold material connector comes into contact with a mold material side plate portion, and FIG. 12B is a perspective view taken along line AA of FIG. FIG. 3 is an enlarged view showing the frame material side plate portion sandwiched therebetween.

FIG. 13 (a) is a view showing the possibility of assembling a formwork by applying the concrete formwork connector of each embodiment of the present invention;
FIG. 4B is a perspective view showing a large box culvert as a secondary concrete product, and FIG. 4B is a perspective view showing an L-shaped stop product as a secondary concrete product.

[Explanation of symbols]

1, 30 Concrete shaping material connecting member 2 Inserting shaft 2a Male thread 2b Nut 3 One side holding portion 3a One side holding surface 4 Other side holding portion 4a Other side holding surface 5,6 Forming material side plate portion In the drawings, the same reference numerals denote the same or corresponding elements.

Claims (3)

(57) [Claims] 1. A one-side holding portion having a one-side holding surface extending in a belt shape and having a predetermined length, and a portion perpendicular to the one-side holding surface within an area of the one-side holding surface.
Having a central axis and being provided near one end of the one-side clamping surface;
A cylindrical insertion shaft portion and, in a region near the other end of the one-side holding surface, a second-side holding surface that faces the one-side holding surface in parallel at a predetermined interval, and the one-side holding surface. At the other end thereof , the one-side holding surface and the other-side holding surface , the other-side holding portion being continuous with the one-side holding portion and having a free end positioned at a predetermined distance from the insertion shaft portion. The concree
Surface contact with the mold material for molding
A concrete formwork connector that clamps the formwork material. 2. The concrete formwork connector according to claim 1, wherein at least the one-side holding portion and the other-side holding portion are formed of a resin molded body. 3. The concrete formwork connector according to claim 1, wherein the insertion shaft portion includes a male screw portion on a free end side thereof.