JPH0637445U - Formwork equipment for precast concrete - Google Patents

Abstract

(57) [Summary] [Structure] The reinforcing bar supporting member 5 is fixed to the inner surface of the side plate 12 of the formwork 1. The reinforcing bar supporting member 5 is formed with a through hole 51 whose axis is aligned with the insertion hole 13 of the side plate 12. The screw reinforcing bar 2 is inserted into the through hole 51. For the screw rebar 2,
The lock nut 6 is screwed. The lock nut 6 abuts the reinforcing bar supporting member 5 by a screw action, and presses the end portion of the screw reinforcing bar 2 against a side plate facing the side plate 12 by its reaction. As a result, the screw reinforcing bar 2 is supported and fixed between the two side plates 12. The outer peripheral surface of the lock nut 6 is formed into a tapered surface. A locking hole 61 is formed on the end surface of the lock nut 6 that abuts the reinforcing bar supporting member 5. [Effect] By engaging the pin portion of the spanner with the locking hole 61, the lock nut 6 is rotated by the spanner. Thereby, the lock nut 6 can be taken out from the precast concrete.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a precast concrete formwork device for producing precast concrete having screw reinforcing bars.

[0002]

[Prior art]

 As a conventional mold apparatus of this type, there is one described in Japanese Patent Laid-Open No. 4-115904. As shown in FIG. 5, this formwork device has a formwork 1 and screw rebars 2 as main constituent elements. The mold 1 is formed by a bottom plate 11 and four side plates (side walls) 12 detachably attached to each side of the bottom plate 11 into a rectangular box shape with an open top. An insertion hole 13 is formed in one side plate 12 of the mold 1. On the side plate 12 facing the side plate 12 in which the insertion hole 13 is formed, a support member 14 whose axis is aligned with the insertion hole 13 is fixed by a nut 15.

A screw is formed on the outer circumference of the screw rebar 2, the sleeve 3 is screwed into one end, and is fixed by a nut 31. A lock nut 4 is screwed onto the other end of the screw reinforcing bar 2. The screw rebar 2 is fixed by the lock nut 4 between the two side plates 12 and 12 in the following manner.

That is, in the screw reinforcing bar 2, the sleeve 3 fixed to one end of the screw reinforcing bar 2 is fitted into the support member 14, and the other end is inserted into the insertion hole 13. In this state, the lock nut 4 is pressed against one side plate 12 by a screw action, and the sleeve 3 is pressed against the other side plate 12. As a result, the screw reinforcing bar 2 is supported and fixed between the two side plates 12 and 12.

In the case of producing precast concrete by the above-described mold apparatus, the screw rebar 2 is attached to the mold 1 as described above, and then the concrete is placed in the mold 1. Then, after the concrete is solidified, the formwork 1 is disassembled and the bottom plate 11 and the side plate 12 are removed from the concrete.

[0006]

[Problems to be solved by the device]

 When precast concrete is manufactured by the above-mentioned conventional formwork apparatus, as shown in FIG. 6, since the lock nut 4 is embedded in the concrete C, the lock nut 4 cannot be rotated. Therefore, there is a problem that the lock nut 4 cannot be taken out from the concrete C.

[0007]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention has a formwork in which concrete is placed, a screw rebar with a screw formed on the outer periphery, and a lock nut screwed to one end of the screw rebar. And the lock nut and the other end of the screw rebar are pressed against the inner surfaces of the two opposite side walls of the form by the screw action between the screw rebar and the lock nut, respectively, to form the screw rebar. In the precast concrete formwork device fixed to the frame, the outer peripheral surface of the lock nut is formed into a circular cross section, and the lock nut is attached to the end surface of the lock nut pressed against the inner surface of the side wall of the formwork. The feature is that a locking portion for locking the jig for rotating is formed.

In this case, the lock nut is preferably composed of two nut halves so that the lock nut can be divided into two parts by a plane including the axis thereof, for the reason described later.

[0009]

[Action]

 After removing the solidified concrete from the form, lock the lock nut with a jig such as a spanner. Then, the lock nut is rotated by this jig to remove it from the concrete. In this case, if the lock nut is one piece, the lock nut must be moved by the length that the screw reinforcing bar protrudes from the concrete, but if the lock nut can be divided into two parts, the lock nut can be separated from the concrete. After pulling out, it can be removed from the screw rebar immediately by dividing it in two.

[0010]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. In the following examples, the same parts as those in the above-mentioned conventional example are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 is a cross-sectional view showing a main part of a formwork apparatus according to the present invention. A reinforcing bar supporting member 5 is attached to an inner surface of a side plate (side wall) 12 having an insertion hole 13 formed therein. The reinforcing bar supporting member 5 is in the shape of a disk, and the outer peripheral surface thereof is formed in a taper shape whose diameter gradually decreases from the side plate 12 side toward the inner side, and a through hole 51 is formed in the center thereof. Has been done. The reinforcing bar supporting member 5 is fixed to the side plate 12 with the bolt 7 in a state where the axis of the through hole 51 is aligned with the axis of the insertion hole 13. Reference numeral 8 is an O-ring, and the O-ring 8 ensures water tightness between the screw reinforcing bar 2 and the reinforcing bar supporting member 5, and the reinforcing bar 2 supports the reinforcing bar 2 through the O ring 8. Supported by.

A lock nut 6 is screwed onto the screw reinforcing bar 2. The outer peripheral surface of the lock nut 6 is formed into a tapered surface whose axis coincides with that of the screw hole 61. This tapered surface is formed as a tapered surface having the same degree of taper as the outer peripheral surface of the reinforcing bar supporting member 5, and the diameters of the end surfaces of the reinforcing bar supporting member 5 and the lock nut 6 that abut against each other are equal. Therefore, the outer peripheral surface of the reinforcing bar supporting member 5 and the outer peripheral surface of the lock nut 6 form one continuous taper surface.

Further, a plurality of (four in this embodiment) locking holes (locking portions) 62 are formed in the end surface of the lock nut 6 facing the reinforcing bar supporting member 5. The locking hole 62 is for fitting a jig for rotating the nut, for example, a pin portion formed on a spanner, and as shown in FIG. Are arranged on the same circumference centered on.

When manufacturing a screw reinforced concrete by the above-mentioned formwork device, the lock nut 6 is rotated by a pipe wrench or the like. Then, the lock nut 6 is pressed against the side plate 12 via the reinforcing bar supporting member 5 by the screw action between the lock nut 6 and the screw reinforcing bar 2. Of course, similarly to the conventional formwork device, the other end of the screw rebar 2 is pressed against the side plate 12 via the screw sleeve 3 (see FIG. 5), whereby the screw rebar 2 is attached to the two side plates 12 respectively. , 12 are supported and fixed.

After fixing the screw rebar 2 to the formwork 1, concrete is placed in the formwork 1. After the concrete solidifies, the formwork 1 is disassembled and the bottom plate 11 and the side plate 12 are removed from the concrete. At this time, the reinforcing bar support member 5 is removed from the concrete together with the side plate 12.

When the reinforcing bar supporting member 5 is removed from the concrete together with the side plate 12, the end surface of the lock nut 6 having the locking hole 62 is exposed to the outside. Then, the pin portion of the wrench is fitted into the locking hole 62, and the lock nut 6 is rotated by the wrench. In this case, since the outer peripheral surface of the lock nut 6 is circular, the lock nut 6 can be easily rotated. When the lock nut 6 is rotated, the lock nut 6 is moved from the concrete to the outside by a screw action, whereby the lock nut 6 can be removed from the concrete. In particular, in this embodiment, since the outer peripheral surface of the lock nut 6 is tapered, even if the lock nut 6 moves slightly outward, the lock nut 6 separates from the concrete. Therefore, it can be easily rotated thereafter by hand.

Next, another embodiment of the present invention shown in FIGS. 3 and 4 will be described. In this embodiment, the through hole 51 of the reinforcing bar supporting member 5 is formed of an outer small-diameter hole portion 52 and an inner large-diameter hole portion 53, and between the small-diameter hole portion 52 and the large-diameter hole portion 53. A step surface 54 is formed on the. A tapered portion 55 is formed at the intersection of the step surface 54 and the inner peripheral surface of the small diameter hole portion 52.

Further, the lock nut 6 is composed of two nut halves 6A and 6B so that the lock nut 6 can be divided into two in the radial direction by a plane including the axis of the screw hole 61. The two nut halves 6A and 6B are formed in the same shape, and the lock nut 6 is formed by abutting them. The lock nut 6 including the two nut halves 6A and 6B has an outer diameter that is substantially the same as the inner diameter of the large diameter hole portion 53, and one end of the lock nut 6 is rotatable in the large diameter hole portion 53. It is inserted freely and freely. The two nut halves 6A and 6B can behave as one lock nut 6 by being inserted into the large-diameter hole portion 53.

An O-ring 9 is mounted between the lock nut 6 and the tapered surface 55 of the reinforcing bar supporting member 5. The O-ring 9 is pressed by the tapered surface 55 and the end surface of the lock nut 6 so that the inner peripheral surface thereof is pressed against the threaded reinforcing bar 2, whereby the threaded reinforcing bar 2 and the reinforcing bar supporting member 5 are separated from each other. The watertightness between them is secured. Further, reference numeral 10 is an O-ring for ensuring water tightness between the reinforcing bar supporting member 5 and the lock nut 6.

When the precast concrete is manufactured by the above-mentioned formwork apparatus, the screw rebar 2 is previously inserted into the through hole 13 of the side plate 12 and the through hole 51 of the rebar supporting member 5. Next, the two nut halves 6A and 6B are butted against each other from both sides of the screw rebar 2 to form one lock nut 6. Then, the lock nut 6 is rotated, and one end of the lock nut 6 is inserted into the large-diameter hole portion 53 of the reinforcing bar supporting member 5 until it abuts on the step surface 54.

Here, the nut halves 6 A and 6 B are butted against each other at a position close to the reinforcing bar supporting member 5, so that the rotation amount for inserting the lock nut 6 into the large diameter hole portion 53 of the reinforcing bar supporting member 5 is increased. Can be reduced. Moreover, if the lock nut 6 is integrally formed, the lock nut 6 must be rotated and moved from the end of the screw rebar 2 to the position where the nut halves 6A and 6B are butted. The lock nut 6 of the present invention does not require such movement due to the rotation, and the lock nut 6 can be easily attached to the screw rebar 2 at a predetermined position.

Next, the outer periphery of the end of the lock nut 6 protruding from the large-diameter hole 53 is clamped and rotated by a pipe wrench, the lock nut 6 is abutted against the step surface 54, and the screw rebar 2 is screwed. It abuts the side plate 12 via the sleeve 3 (see FIG. 5), whereby the screw rebar 2 is fixed between the two side plates 12, 12 of the formwork 1. Next, concrete is placed in the mold 1. After the concrete is solidified, the formwork 1 is disassembled and the bottom plate 11 and the side plate 12 are removed from the concrete to obtain precast concrete.

When removing the lock nut 6 from the precast concrete manufactured as described above, the wrench is rotated with the pin of the wrench fitted in the locking hole 62, and the lock nut 6 is rotated. Remove from concrete. When the entire lock nut 6 comes out of the concrete, divide the lock nut 6 in two and remove it from the screw rebar 2. Therefore, it is not necessary to rotate the lock nut 6 to move it to the end of the screw rebar 2, and the lock nut 6 can be removed from the screw rebar 2 in a short time.

It should be noted that the present invention is not limited to the above-described embodiments, and can be modified as appropriate without departing from the spirit of the invention. For example, in the above embodiment, the locking hole 62 is formed as a locking portion for locking the jig for rotating the nut such as the spanner, but the jig is locked and Therefore, it goes without saying that another one may be used as long as it can rotate the lock nut 6. Moreover, the number of the locking holes 62 is not limited to four, but may be arbitrary.

Further, in the above-described embodiment, the lock nut 6 is pressed against the side plate 12 via the reinforcing bar supporting member 5, but the lock nut 6 may be pressed directly against the side plate 12.

Further, in the embodiment shown in FIGS. 3 and 4, the two nut halves 6 A and 6 B are fitted into the large-diameter hole portion 53 of the reinforcing bar supporting member 5 to form one lock nut 6. Although it is configured to behave, if an engaging mechanism that detachably integrates the two nut halves 6A and 6B is provided between the two nut halves 6A and 6B, the nut halves 6A and 6B are fitted into the large diameter hole portion 53. You don't have to. In particular, in such a case, as shown by an imaginary line in FIG. 3, if the outer peripheral surface of the lock nut 6 protruding to the outside from the large-diameter hole portion 53 is formed into a tapered surface, the lock nut 6 is made of concrete. It can be removed more easily.

[0027]

[Effect of device]

 As described above, according to the precast concrete formwork device of the present invention, the outer periphery of the lock nut is formed into a circular cross section, and a jig for rotating a nut such as a spanner on the end face of the lock nut facing the side plate. Since the locking portion for locking the lock nut is formed, the lock nut can be easily pulled out from the concrete by locking the jig on the lock nut and rotating the jig. When the lock nut is composed of two nut halves, the lock nut can be attached to the screw rebar by sandwiching the two nut halves from both sides at arbitrary points of the screw rebar, and at the same time extracting from concrete. It is not necessary to move the lock nut to the end of the screw rebar. Therefore, the lock nut can be attached and detached more easily.

[Brief description of drawings]

FIG. 1 is a sectional view showing an essential part of an embodiment of the present invention.

2 is a plan view of a lock nut used in the embodiment shown in FIG. 1. FIG.

FIG. 3 is a sectional view showing an essential part of another embodiment of the present invention.

FIG. 4 is a plan view of a lock nut used in the embodiment shown in FIG.

FIG. 5 is a partially omitted sectional view showing an example of a conventional formwork device for precast concrete.

FIG. 6 is an enlarged view showing a state in which a lock nut is buried in concrete.

[Explanation of symbols]

 1 Formwork 12 Side plate (side wall) 2 Screw rebar 6 Lock nut 6A Nut half 6B Nut half 61 Screw hole 62 Locking hole (locking part)

Continued Front Page (72) Creator Koichi Ebine 13508-3 Yuki, Yuki City, Ibaraki Prefecture

Claims (2)

[Scope of utility model registration request] 1. A formwork in which concrete is cast, a screw rebar having a screw formed on the outer periphery thereof, and a lock nut screwed to one end of the screw rebar. The lock nut and the other end of the screw rebar are opposed to each other by the screw action between the lock nut and the form 2
In the precast concrete formwork device in which the screw rebars are fixed to the formwork by pressing against the inner surfaces of the two side walls, the outer peripheral surface of the lock nut is formed into a circular cross section, and the inner surface of the side wall of the formwork is formed. A precast concrete formwork device characterized in that a locking portion for locking a jig for rotating the lock nut is formed on an end surface of the lock nut to be pressed. 2. The formwork apparatus for precast concrete according to claim 1, wherein the lock nut is composed of two nut halves so that the lock nut can be divided into two parts by a plane including the axis thereof.