JP2007321420A - Reinforcing bar holder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reinforcing bar holder which is suitably usable in the case where a reinforcement embedded in concrete is held, etc., wherein the reinforcing bar holder can hold the reinforcing bar without being broken even if an excessive axial force is introduced to the holder that has been squeezed into a through hole in a form, when pulled upward. <P>SOLUTION: The reinforcement holder has a hook member 10, a screw joint portion 12, and an anchor member 11 which has a tip insertion member 20, an umbrella seat 21, and a stopper 22. Herein the umbrella seat 21 is formed with a plurality of leading wings 35, and the tip insertion member 20 is formed with a plurality of following wings 29. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a reinforcing bar holder that can be suitably used for holding a reinforcing bar embedded in concrete.

In recent years, for the purpose of reducing the weight of a reinforced concrete structure and improving the sound insulation, a method of embedding a spherical polystyrene-made embedded object (hereinafter referred to as “spherical void”) in a slab has been put into practical use (for example, see Non-Patent Document 1). ).
In this method, concrete is placed with a large number of ball voids placed and fixed in the mold, and the ball voids are embedded. However, by placing reinforcing bars above the ball voids, In addition to preventing the voids from lifting, the reinforcing bars are prevented from being pushed up by the spherical voids by connecting the reinforcing bars and the formwork with stoppers.

In this case, the male screw part provided at the lower end of the stopper metal is inserted into the through-hole formed in the mold, and the nut is screwed into the portion that protrudes downward from the mold. There is a problem that workers are required on both the upper side and the lower side of the machine, and that the work takes a lot of time.
Therefore, in order to solve this problem, the anchor to be attached to the formwork using the through hole formed in the formwork, and the lower end portion is simply pushed into the anchor while the upper end portion is hooked on the reinforcing bar. A one-touch hardware has been proposed in which a latch that can be connected in a non-detachable state is set (see Patent Document 1).

The anchor itself is held in a state where it sits on the upper surface of the formwork, but when this anchor is pushed into the through-hole from above the formwork, it becomes a closed shape like a flower bud and penetrates the through-hole. After the penetration, a stopper member called a parachute that opens as a flower blooms was bolted.
RC housing complex using “spherical voids” Building Technology 2003. March issue 228 pages to 234 pages (issued March 1, 2003) JP 2005-188265 A

In the above conventional one-touch hardware, the upper end of the stopper member (the portion that opens in the shape of a petal) is formed in a curved shape. Therefore, when a strong tensile force acts on the anchor by the latch, the stopper member is attached via a bolt. May be damaged due to crushing that causes the stopper member to be crushed in the axial direction while causing excessive opening deformation, or local buckling due to insufficient flowering. was there.
The present invention has been made in view of the above circumstances, and provides a reinforcing bar holding tool capable of holding a reinforcing bar without being damaged even when an excessive axial force is introduced during retraction after being pushed in. With the goal.

In order to achieve the above object, the present invention takes the following technical means.
That is, the reinforcing bar holder according to the present invention can be penetrated into the hook member 10 that can be engaged with the reinforcing bar 5 arranged along the mold 2 and the through hole 2 a formed in the mold 2. An anchor member 11, and a screw connection portion 12 that is screwed into the members 10 and 11 in a state where the hook member 10 and the anchor member 11 are directed in opposite directions, and the anchor member 11 is connected to the through hole. A rebar holding tool for holding the rebar 5 in a state where the anchor member 11 is pushed into the outer surface of the mold 2 after being pushed into 2a,
The anchor member 11 includes a distal end insertion member 20 that can be inserted through the through hole 2a, an umbrella seat 21 that is disposed at a position where the distal end insertion member 20 is inserted into the through hole 2a, and a distal end insertion. And a stopper 22 for restricting movement of the member 20 and the umbrella seat 21 during the push-in, and the umbrella seat 21 can be deformed by being deflated to an outer diameter passing through the through-hole 2a when pushed into the through-hole 2a. A plurality of leading wings 35 that can be restored and expanded are provided, and the tip insertion member 20 is guided to the leading wing 35 at the end facing the umbrella seat 21 when retracted. A secondary wing 29 is formed which expands in the radially outward direction of the hole 2 a and is pressed against the outer surface of the mold 2.

Among these, the umbrella seat 21 is formed in a conical shape having a diameter larger than the through hole 2a of the mold 2 and smaller in diameter toward the distal end insertion member 20, and is a concentric circle provided on the larger diameter side. A thin tapered outer wall 33 is formed around the circular spot facing portion 32, and radial cracks 34 at the center of the screw connection portion 12 are formed at a plurality of locations in the circumferential direction of the tapered outer wall 33, whereby the plurality of leading wings 35 are formed. Is preferably formed.
Further, the tip insertion member 20 is formed in a columnar shape having an outer diameter equal to or smaller than that of the through hole 2a of the mold 2, and a concentric circular seat provided on the side facing the umbrella seat 21. A plurality of secondary wings 29 are preferably formed by forming a thin peripheral wall 26 around the groove portion 25 and forming a radial crack 27 at the center of the screw connection portion 12 in the peripheral wall 26.

  As described above, the anchor member 11 included in the reinforcing bar holder according to the present invention includes the umbrella seat 21 provided with the leading wing 35 and the distal end insertion member 20 provided with the secondary wing 29. When the anchor member 11 is once pulled through the through-hole 2a of the mold 2 and then retracted, the leading wing 35 of the umbrella seat 21 is expanded and deformed as a restoration after being deflated. Further, the secondary wings 29 of the tip insertion member 20 are expanded and deformed so as to be guided to the leading wings 35. Finally, the secondary wings 29 are pressed against the outer surface of the mold 2 to form through holes. An engagement force is generated around 2a.

Here, the secondary wing 29 is surely and smoothly expanded in diameter by the leading wing 35, and generates an engagement force around the through hole 2a in a state of being appropriately expanded in the radial direction.
Therefore, even when an excessive tensile force (axial force) is introduced into the anchor member 11 by being pulled into the through hole 2a of the mold 2, the anchor member 11 leading wing 35 is provided. There is no possibility that the tip insertion member 20 provided with the umbrella seat 21 and the sub wing 29 is damaged in an unsupportable state, and the workability of the reinforcing bar holding work is improved. Moreover, since the tip insertion member 20 is effectively pressed against the mold 2 by the tensile force, the reinforcing bar 5 can be firmly fastened to the mold via the reinforcing bar holder of the present invention. Furthermore, it is possible to prevent rattling from occurring after attachment to the mold 2.

Moreover, it is preferable that the circular spot facing portion 25 formed on the distal end insertion member 20 of the anchor member 11 is a tapered hole.
By doing so, the distal end insertion member 20 comes into contact with the tapered outer wall 33 of the umbrella seat 21 against the inner peripheral surface of the tapered hole, and this contact portion of the distal end insertion member 20, i.e., the follower. Since the wing 29 is gradually tapered toward the tip, the expanding deformation along the leading wing 35 of the umbrella seat 21 is performed more reliably and smoothly.
Further, the tip insertion member 20, the umbrella seat 21 and the stopper 22 of the anchor member 11 are provided with center holes 20a, 21a and 22a at the centers thereof, and a bolt head 24a is provided at one end thereof. It is preferable that the tip insertion member 20, the umbrella seat 21 and the stopper 22 are inserted in a skewered manner in this order with respect to the bolt 24, and the tip insertion member 20 is prevented from being pulled out by the bolt head 24a. . In this way, the structure can be simplified.

  In the reinforcing bar holder according to the present invention, it is possible to hold the reinforcing bar without damaging it in an unsupportable state even when an excessive axial force is introduced at the time of retraction after being pushed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 11 shows an embodiment in the case of constructing a concrete slab with reduced weight and improved sound insulation using the reinforcing bar holder 1 according to the present invention. The grids are arranged in a grid pattern, and the ball voids 4 are arranged vertically and horizontally on the upper part, and upper end bars serving as the presser bars 5 are arranged on the ball voids 4. In this state, an upper mold (not shown) is provided above the presser bar 5, and concrete is placed between the two molds.
Each spherical void 4 is made of a material having a specific gravity lighter than concrete such as polystyrene foam or polyethylene foam, and is formed in a substantially spherical shape. The center of the sphere is positioned so as to penetrate like a skewer.

In the following, the lower mold 2 is simply referred to as “form 2”, and the presser bar 5 is simply referred to as “rebar 5”.
As shown in FIG. 1 (an enlarged sectional view taken along line AA in FIG. 11) and FIG. 2 (a side view in an unused state), the reinforcing bar holder 1 includes a hook member 10 and an anchor member 11. Yes. The hook member 10 and the anchor member 11 are connected to each other via a screw connecting portion 12, and can be rotated relative to the screw connecting portion 12 by tightening or loosening the screw. The overall axial length is variable by rotation.

The screw connecting portion 12 shown in this embodiment forms a first screw joint 13 with the hooking member 10 and can also form a second screw joint 14 with the anchor member 11. Is used. The hook member 10 and the anchor member 11 are provided with male screws 13a and 14a, respectively, and both ends of the intermediate member 15 are provided with female screws 13b and 14b corresponding to the male screws 13a and 14a.
Although the first screw joint 13 and the second screw joint 14 have the same screw pitch, they are in a reverse screw relationship with each other (the first screw joint 13 is a left screw and the second screw joint 14 is a right screw). The screw connection portion 12 is configured by a turnbuckle as a combination of the hook portion 10, the intermediate member 15 and the anchor portion 11, and the forward rotation (right rotation) or reverse rotation (left rotation) of the relay member 15 is configured. By doing so, the hook portion 10 and the anchor portion 11 can be brought close to each other at a distance twice the screw pitch, or can be relatively separated from each other.

The hooking member 10 is formed of a rod having a diameter of about 7 mm, and the male screw 13a is provided at one end thereof, and the rod is bent into a U-turn at the opposite end. Thus, a hook portion 17 for engaging with the reinforcing bar 5 (see FIG. 11) arranged along the mold 2 is provided.
On the other hand, the anchor member 11 has a tip insertion member 20, an umbrella seat 21, and a stopper 22. The tip insertion member 20, the umbrella seat 21 and the stopper 22 are provided with center holes 20a, 21a and 22a at their centers, and these bolts 24 are provided with bolt heads 24a at one end. The tip insertion member 20, the umbrella seat 21, and the stopper 22 are inserted in a skewered manner in this order so that a rotatable state around the screw connecting portion 12 is obtained.

That is, the tip insertion member 20 is prevented from being pulled out by the bolt head 24a of the bolt 24, and the umbrella seat 21 is positioned closer to the screw connecting portion 12 than the tip insertion member 20, and the umbrella seat 21 is The stopper 22 is provided in such an arrangement that it is positioned closer to the distal end insertion member 20 so as not to come out of the screw connecting portion 12. The above-described male screw 14 a is formed by the bolt end protruding from the stopper 22.
When the anchor member 11 is viewed from the male screw 14a side, the stopper 22, the umbrella seat 21, and the tip insertion member 20 are arranged in the extending direction along the axial direction with respect to the screw connecting portion 12. I can say that.

As shown in FIGS. 3 and 4, the tip insertion member 20 is formed in a columnar shape (cylindrical because the central hole 20 a is provided) by resin or the like, and on the side facing the umbrella seat 21, A concentric circular spot facing portion 25 is provided. The outer diameter of the columnar shape is equal to or less than that of the through hole 2a provided in the mold 2 and can be inserted into the through hole 2a.
By providing the circular spot facing portion 25, a thin peripheral wall 26 is formed therearound. In this embodiment, the circular spot facing portion 25 is formed as a tapered hole, and therefore the peripheral wall 26 is shown. Is tapered toward its tip (end toward the umbrella seat 21) and gradually becomes thinner.

A plurality of cracks 27 (four in the illustrated example) are formed in the peripheral wall 26 in a radial arrangement centered on the screw connection portion 12. The crack 27 is formed shallower than the columnar axial length formed by the outer shape of the tip insertion member 20 (that is, the crack 27 does not extend to the entire columnar axial direction). The insert member 20 is provided with a cylindrical body portion 28 where the crack 27 does not reach.
Thus, the portion that remains between the cracks 27 in the circumferential direction becomes the secondary wing 29 (the operation of the secondary wing 29 will be described later). The secondary wing 29 is thinned as the peripheral wall 26, and the peripheral wall 26 is divided in the circumferential direction by a plurality of radially arranged cracks 27. It can be elastically deformed or plastically deformed in the radially outward direction.

As shown in FIGS. 5 and 6, the umbrella seat 21 is formed in a conical shape by resin, and a concentric circular counterbore portion 32 is provided on the large diameter side. The outer diameter on the larger diameter side is larger than that of the through hole 2 a of the mold 2, and the outer diameter on the smaller diameter side is set to fit into the circular spot facing portion 25 of the tip insertion member 20. .
By providing the circular spot facing portion 32, a thin tapered outer wall 33 is formed therearound. In this embodiment, the circular spot facing portion 32 is formed as a tapered hole, and therefore the tapered outer wall is shown. The thickness of 33 is gradually reduced toward the outer peripheral edge.

The tapered outer wall 33 is formed with a plurality of cracks 34 (four in the illustrated example) in a radial arrangement centered on the screw connection portion 12. In the present embodiment, the crack 34 is formed as a fan-shaped notch, but may be formed in a slit shape or the like.
Thus, the portion that remains between the cracks 34 in the circumferential direction becomes the leading wing 35. The leading wing 35 is reduced in thickness as the tapered outer wall 33, and the distal end insertion member is formed by dividing the tapered outer wall 33 in the circumferential direction by a plurality of radially arranged cracks 34. It has elasticity and elastic restoring force that expand and contract in the radial direction of 20. Therefore, even if the diameter is larger than the through hole 2a of the mold 2, it can be deformed by being deformed to the outer diameter passing through the through hole 2a when being pushed into the through hole 2a, and is restored and expanded after being pushed. .

The stopper 22 is formed of a nut that can be screwed into a bolt 24 that forms the male screw 14a. Therefore, by appropriately adjusting the screwing degree with respect to the bolt 24, the axial position of the male screw 14a can be arbitrarily set, and the axial movement of the tip insertion member 20 and the umbrella seat 21 with respect to the bolt 24 is prevented at the set position, Acts as a retaining.
The stopper 22 is not limited to a nut, and may be replaced with a spacer (sleeve-like one) that maintains a predetermined distance between the intermediate member 15 and the umbrella seat 21.
Next, the usage method of the reinforcing bar holder 1 according to the present invention will be described.

As shown in FIG. 11, the lower end bars 3 are arranged in a grid pattern on the mold 2, and the ball voids 4 are arranged vertically and horizontally on the upper part, and the reinforcing bars (presser bars) 5 are placed on the ball voids 4. As shown in FIG. 7, the anchor member 11 of the reinforcing bar holder 1 is pressed against the through-hole 2 a provided in the formwork 2 as appropriate.
In the anchor member 11, the distal end insertion member 20 has a diameter equal to or smaller than that of the through hole 2a, so that it can be inserted without difficulty as shown in FIG. The umbrella seat 21 is larger in diameter than the through-hole 2a, but this large-diameter portion has elasticity and elastic restoring force that expand and contract in the radial direction of the distal end insertion member 20 as a leading wing 35. It passes through the through-hole 2a without any difficulty with its deformation. In this way, the anchor member 11 penetrates through the through hole 2a as a whole, and the umbrella seat 21 expands by restoring the leading wing 35 as shown in FIG.

Thereafter, the reinforcing bar holder 11 is pulled so that the distal end insertion member 20 and the umbrella seat 21 of the anchor member 11 are pulled into the mold 2.
At this time, the anchor member 11 has an action in the direction of being pulled out (retracted) from the through hole 2a, and as shown in FIG. 10, it is guided to the leading wing 35 of the umbrella seat 21 expanded by restoration, The secondary wing 29 of the tip insertion member 20 is caused to expand and deform.
Finally, as shown in FIG. 1, the leading wing 35 and the secondary wing 29 are doubled, and the secondary wing 29 of the tip insertion member 20 is pressed against the mold 2 to surround the through hole 2a. Thus, an engaging force is generated.

At this time, the strength of the distal end insertion member 20 can be increased by the presence of the cylindrical body portion 28, and the secondary wing 29 is locally buckled due to crushing or lack of flowering, such as being crushed in the axial direction. ) Etc. will not be damaged. Further, there is no backlash with respect to the mold 2.
Thereafter, the hook part 17 of the hooking member 10 is hooked on the reinforcing bar 5 (see FIGS. 1 and 11), and the joint member 15 is rotated at the screw connecting part 12 (operation toward the relative proximity in the axial direction). Then, the hook portion 10 and the anchor portion 11 are relatively close to each other like a turnbuckle to adjust the length. As a result, the mold 2 and the reinforcing bar 5 can be reliably and firmly connected.

The present invention is not limited to the above embodiment.
For example, the screw connecting portion 12 is not limited in that it includes the intermediate member 15 as a turnbuckle, and it is sufficient that at least the hook member 10 and the anchor member 11 can be connected by a screw structure.
In the anchor member 11, the number of formation in the circumferential direction is not particularly limited in the sub wing 29 of the tip insertion member 20 and the leading wing 35 of the umbrella seat 21.
In addition, the anchor member 11 according to the present embodiment has a through-hole formed in, for example, a plate-shaped wall surface, and can be engaged with the wall surface simply by pressing and pulling into the through-hole. In addition to being employed to do so, there is also an application as a member for fastening (fastening) another member to a wall surface.

It is a side view which shows the use condition of the reinforcing bar holder which concerns on this invention. It is a side view which shows the unused state of the reinforcing bar holder which concerns on this invention. It is the perspective view which showed the front-end | tip insertion member. It is the perspective view which showed the front-end | tip insertion member from the reverse direction to FIG. It is the perspective view which showed the umbrella seat. It is the perspective view which showed the umbrella seat from the reverse direction to FIG. It is a principal part sectional side view which showed the use procedure of a reinforcing bar holder. It is principal part side sectional drawing which showed the use procedure following FIG. It is principal part side sectional drawing which showed the use procedure following FIG. FIG. 10 is a side cross-sectional view showing a main part of the usage procedure following FIG. 9. It is the side view which showed the use condition of the reinforcing bar holder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rebar holder 2 Formwork 2a Through-hole 4 Ball void 5 Rebar 10 Hook member 11 Anchor member 12 Screw connection part 13 Screw joint (1st screw joint)
14 Screw joint (second screw joint)
14a Male screw 15 Joint member 17 Hook portion 20 Tip insertion member 20a Center hole of tip insertion member 21 Umbrella seat 21a Center hole of umbrella seat 22 Stopper 22a Center hole of stopper 24 Bolt 24a Bolt head 25 Circular shape of tip insertion member Counterbore part 26 Peripheral wall 27 Radial crack of the tip insertion member 28 Cylindrical body part 29 Sub wing 32 Circular counterbore part of the umbrella seat 33 Tapered outer wall 34 Radial crack of the umbrella seat 35 Leading wing

Claims (5)

The hook member (10) that can be engaged with the reinforcing bar (5) arranged along the mold (2) and the through hole (2a) formed in the mold (2) can be penetrated. The anchor member (11) has a screw connection portion (12) that is screwed into the two members (10, 11) in a state where the hook member (10) and the anchor member (11) are directed in opposite directions. Then, the anchor member (11) is pushed into the through hole (2a) and then pulled, and the anchor member (11) is pushed against the outer surface of the mold (2) to hold the reinforcing bar (5). Because
The anchor member (11) is arranged at a tip insertion member (20) that can be inserted through the through hole (2a), and at a position where the anchor member (11) is inserted into the through hole (2a) following the tip insertion member (20). And a stopper (22) for restricting the movement of the front end insertion member (20) and the umbrella seat (21) during the push-in operation, the umbrella seat (21) has a through hole ( 2a) is provided with a plurality of leading wings (35) that can be deformed by shrinking to the outer diameter passing through the through hole (2a) at the time of pushing into the through hole (2a), and that can be restored and expanded after pushing, 20), at the end facing the umbrella seat (21), the guide wing (35) guides the retracted end wing to expand outward in the radial direction of the through hole (2a). Characterized in that a secondary wing (29) is formed which is pressed against the outer surface of Holder.   The umbrella seat (21) is formed in a conical shape having a diameter larger than that of the through hole (2a) of the mold (2) and smaller in diameter toward the tip insertion member (20). A thin tapered outer wall (33) is formed around the concentric circular counterbore portion (32) provided, and the center of the screw connection portion (12) is radially formed at a plurality of locations in the circumferential direction of the tapered outer wall (33). The reinforcing bar holder according to claim 1, wherein the plurality of leading wings (35) are formed by forming cracks (34).   The tip insertion member (20) has an outer diameter equal to or smaller than that of the through hole (2a) of the mold (2) and is formed in a columnar shape, and is provided on the side facing the umbrella seat (21). A thin peripheral wall (26) is formed around the concentric circular spot facing portion (25), and a radial crack (27) at the center of the screw connection portion (12) is formed on the peripheral wall (26). The reinforcing bar holder according to claim 2, wherein the plurality of secondary wings (29) are formed.   The reinforcing bar holder according to claim 3, wherein the circular spot facing portion (25) formed in the tip insertion member (20) of the anchor member (11) is a tapered hole. A center hole (20a, 21a, 22a) is provided at the center of the tip insertion member (20), the umbrella seat (21) and the stopper (22) of the anchor member (11), and a bolt is provided at one end. The tip insertion member (20), the umbrella seat (21), and the stopper (22) are inserted in a skewered manner in this order with respect to the bolt (24) provided with the head (24a), and the bolt head (24a The reinforcing bar holder according to any one of claims 1 to 4, wherein the distal end insertion member (20) is in a state of being withdrawn.

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