JPH0444729Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention Industrial Application Field The present invention relates to a spacer that is attached to reinforcing bars and maintains the distance between the formwork and the reinforcing bars to ensure the cover thickness of the reinforcing bars in reinforced concrete.

Prior Art Conventionally, donut-shaped spacers used to ensure the thickness of reinforcing bars in walls, columns, etc. have been integrally molded entirely from plastic. FIG. 8 is a top view of a conventional spacer 20, where 21 is a reinforcing hole,
22 is a notch for mounting, 23 is a protrusion for preventing falling off,
24 is a void. The spacer 20 has a notch 22
It is installed by passing the reinforcing bar through the reinforcing bar and fitting the reinforcing bar into the reinforcing bar hole 21. When the protrusion 23 is attached to the reinforcing bar, it is elastically deformed and guides the reinforcing bar to the reinforcing bar hole 21, but once attached, the reinforcing bar cannot be easily removed from the reinforcing bar hole 21, and the spacer 20 is prevented from falling off. be. The void 24 is provided primarily to save material.

Problems to be solved by the invention Figure 9 is a cross-sectional view of reinforced concrete using a spacer 20, but since the spacer 20 is made of plastic, there are differences in thermal expansion coefficient with concrete, shrinkage of concrete, etc. A gap 25 is created between the spacer 20 and the concrete C. There is a problem in that moisture such as rainwater and groundwater enters the concrete C from the outside through the gap 25, passes through the spacer 20, reaches the reinforcing bars T, and causes corrosion of the reinforcing bars T.

The present invention provides a spacer that is less likely to form a gap between the reinforcing bar and the concrete that causes corrosion.

Means for Solving Problems in the Structure of the Invention The present invention is a donut-shaped spacer having a central reinforcing bar hole and a notch for installation extending from the outer circumferential direction to the reinforcing bar hole. an outer piece made of mortar, the inner piece has flanges projecting outward at the top and bottom of the outer circumference, and the inner circumferential end of the outer piece is rotatably fitted into a groove formed by the upper and lower flanges and the outer circumferential surface. This spacer is characterized by:

The mortar that forms the outer piece may be a normal mortar made by mixing cement, sand, and water, but it is preferable to improve its strength by press-molding a hard-mixed mortar or by using glass fiber reinforced cement. .

In order to make the outer piece rotatable relative to the inner piece,
It is desirable that the outer diameter of the inner piece be slightly smaller than the inner diameter of the outer piece.

Function The spacer of the present invention consists of a C-shaped outer piece made of mortar and an inner piece made of plastic. Concrete and mortar have approximately the same coefficient of thermal expansion and are compatible with each other and adhere well to each other, so it is difficult to form a gap between the outer piece of the spacer and the concrete. Therefore,
There is less risk of moisture penetrating into the concrete through the spacer. Since the outer piece is rotatably fitted to the inner piece, in other words, the inner piece is rotatable relative to the outer piece, so after attaching it to the reinforcing bar, rotate the inner piece, and as shown in Figure 2. As shown, if the reinforcing bar hole 4 is closed to the mounting notch 5, the reinforcing bar T
The spacer 1 attached to the spacer 1 is prevented from falling off. Since the inner piece is made of plastic, it is easy to manufacture, and because it is highly elastic, it can be easily attached to the outer piece so as to be rotatable.

Example 1 Figures 1 to 6 relate to the spacer 1 of Example 1, in which Figure 1 is a top view, Figure 2 is a top view showing a state in which the inner piece is rotated to close the reinforcing bar hole, and Figure 3 is a top view. 1
4 is a perspective view of the inner piece, FIG. 5 is a perspective view of a rotating tool for the inner piece, and FIG. 6 is a perspective view of the formwork.

The spacer 1 consists of a C-shaped inner piece 2 made of plastic and an outer piece 3 made of mortar, and has a central reinforcing bar hole 4 and a notch 5 extending from the outer circumferential direction to the reinforcing bar hole 4, as shown in FIG.

As shown in FIG. 4, the inner piece 2 is made of plastic and has a C-shape, and has flanges 6, 7 on its outer periphery that protrude upward and downward. A groove 9 formed by the upper and lower flanges 6 and 7 and the outer peripheral surface
As shown in FIG. 3, the inner peripheral end of the outer piece 3 is fitted. There are two small holes 8 for rotation on the upper and lower surfaces.
For example, a protrusion 11 of a rotating tool 10 as shown in FIG. 5 can be fitted into a small hole 8 to rotate.

The outer piece 3 is formed by pressing mortar made by hardening cement, sand, and water into a C shape.

As shown in Figure 3. The fact that the outer diameter d of the inner piece is approximately 1 mm smaller than the inner diameter D of the outer piece facilitates rotation of the inner piece relative to the outer piece.

There are two methods for manufacturing the spacer 1. The first method is to manufacture the inner piece 2 and the outer piece 3 separately, and then attach the inner piece 2 to the outer piece 3 through the notch 5 etc. of the outer piece 3 using the elasticity of the inner piece. . The second method is to manufacture the inner piece 2 in advance, attach it to the circular part 13 of the keyhole-shaped core of the formwork 12, and pour mortar into it to harden it, as shown in FIG. It is. In this case, if the diameter of the circular part 13 of the keyhole-shaped core is made slightly larger than the inner diameter of the inner piece 2, the outer diameter of the inner piece 2 will be
It returns to a position slightly smaller than the inner diameter D of the outer piece 3.

Embodiment 2 FIG. 7 is a sectional view of a spacer 14 according to Embodiment 2.

Spacer 14 is a C-shaped plastic inner piece 1
5 and an outer piece 16 made of mortar. Inner piece 15
Flanges 17, 18 are formed above and below the outer circumference of the outer piece 16, and the inner circumferential end of the outer piece 16 is rotatably fitted into a groove formed by the flanges 17, 18 and the outer circumferential surface. A protrusion 19 is formed on the upper surface of the inner piece 15, on which a finger is placed when rotating the inner piece.

The manufacturing of the spacer 14 consists of an inner piece 15 and an outer piece 16.
are made separately in advance, and then the inner piece 15 is replaced with the outer piece 1.
6, this is done by pressing from above as shown by the arrow in FIG. The lower flange 18 is undersized to facilitate attachment of the inner piece to the outer piece.

Effects of the invention The spacer of the invention consists of an outer piece and an inner piece,
Since the outer piece is made of mortar, it adheres well to the concrete, leaving no gaps between the pieces and the concrete, thereby preventing moisture from entering. Since the inner piece is rotatably attached to the outer piece,
After the spacer is attached to the reinforcing steel, the inner piece is rotated and the reinforcing bar hole is closed from the mounting notch, so that the spacer does not fall off from the reinforcing steel. Since the inner piece is made of plastic, it is easy to process, and its elasticity allows it to be easily rotatably attached to the outer piece.

[Brief explanation of the drawing]

1 to 6 relate to the spacer 1 of Example 1, FIG. 1 is a top view, FIG.
4 is a perspective view of the inner piece, FIG. 5 is a perspective view of a rotating tool for the inner piece, and FIG. 6 is a perspective view of the formwork. Figure 7 shows spacer 1 as Example 2.
4 is a sectional view of FIG. Figure 8 shows conventional spacer 2
0 and FIG. 9 are cross-sectional views of reinforced concrete using the spacer 20. 1...Spacer, 2...Inner piece, 3...Outer piece,
4... Rebar hole, 5... Notch, 6... Flange,
7...Flange, 8...Small hole, 9...Groove, 10...
...Rotating tool, 11...Protrusion, 12...Formwork, 13...
... circular part, 14 ... spacer, 15 ... inner piece,
16...Outer piece, 17...Flange, 18...Flange, 19...Protrusion, 20...Spacer, 21
... Rebar hole, 22 ... Notch, 23 ... Protrusion,
24...Gap, 25...Gap, T...Reinforcing bar.

Claims (1)

[Scope of utility model registration request] It is a donut-shaped spacer that has a central reinforcing bar hole and a notch for installation extending from the outer circumference to the reinforcing bar hole, and consists of a C-shaped inner piece made of plastic and an outer piece made of mortar. 1. A spacer having an outwardly projecting flange, the inner peripheral end of the outer piece being rotatably fitted into a groove formed by the upper and lower flanges and the outer peripheral surface.