JPS6140527B2 - - Google Patents

Description

Detailed Description of the Invention The present invention supports a cylindrical outer frame curved in an arc shape on a machine frame, supports annular end plates at the upper and lower ends of the outer frame, and has an opening in the end plate at the lower end. Insert the chevron-shaped upper end of a cylindrical core curved into a circular arc into the section, pour ready-mixed concrete between the core and the outer frame, and while applying vibration to the ready-mixed concrete, change the chevron-shape of the same core. Concrete characterized in that the upper end portion is raised in an arc shape to the outside of the opening of the annular end plate at the upper end of the outer frame, and after the concrete is semi-hardened, the core is moved in an arc shape and removed from the mold. This relates to a method for manufacturing bent pipes.

To explain the embodiment of the present invention shown in the drawings, the lower end flange portion of a cylindrical outer frame 2 which can be divided into two with upper and lower ends open is fixed to a machine frame 1 with bolts 3, and the upper end opening is supported upward. This outer frame 2 is curved in an arc shape around the center line of a horizontal shaft 4 extending from the machine frame 1, and an annular end plate 5 is fixed to the lower end opening with the bolt 3, and the upper end opening is fixed to the outer frame 2. An annular end plate 6 is fixed to the flange with bolts 7. A cylindrical core 8 curved in the shape of an arc with its center line as the center is supported on the horizontal shaft 4 by arms 9, and the center line of the cylindrical core 8 is aligned with the cylinder of the outer frame 2. The chevron-shaped upper end 10 of the core 8 is aligned with the center line of the lower end plate 5.
and close the opening (see Figure 2). In the figure, 11 indicates a reduction gear provided on the horizontal shaft 4, 12 a small gear meshing with the same gear 11, 13 a small gear rotation handle, and 14 a vibrator provided on the machine frame 1.

In the present invention, as described above, in the state shown in FIG. 1, a predetermined amount of fresh concrete 15 is poured into the outer frame 2 from the opening of the end plate 6 at the upper end. In this way, the concrete 15 is held by the lower part of the outer frame 2, the annular end plate 5, and the chevron-shaped upper end part 10. When the vibrator 14 is vibrated in this state, the vibration is transmitted to the outer frame 2, end plate 5, and core 8, and further vibrates the fresh concrete 15. In this vibration state, when the handle 13 is rotated in the direction of the arrow, the core 8 is rotated in the direction of the arrow and rises in a circular arc shape.
Fresh concrete 15 is poured in as described above while being raised, and is vibrated as described above. Then, the upper chevron portion 10 comes out to the outside of the opening of the upper annular end plate 6 to stop the core 8, and after the fresh concrete 15 has semi-hardened, the handle 13 is rotated in the opposite direction to the arrow. The core 8 is lowered from the imaginary line position in FIG. 1 to the solid line position and further lowered to remove the mold. The opening angle Θ of the outer frame 2 can be 90 degrees, in which case the upper end is supported on the machine frame 1 with the upper end facing upward. Therefore, the outer frame 2 is lowered from the position shown in FIG. 1 and supported.

Conventional concrete bent pipes cannot be molded using centrifugal force, and even when using the manual vibration method, reinforcing bars are placed between the inner and outer frames and the pipe thickness is small, making it difficult to pour concrete and making filling difficult. It was difficult.

The present invention has been made in view of the above-mentioned defects, and since the present invention is based on the above-described method, it is possible not only to simplify the production equipment for the concrete curved pipe 16 but also to easily manufacture the arc-shaped concrete curved pipe 16. can be manufactured. That is, even if there is a complicated reinforcement 17 in a narrow gap, the concrete 15 can be easily poured into the gap, and the concrete bent pipe can be mass-produced.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the method for manufacturing a concrete curved pipe according to the present invention, and FIG. 2 is a perspective view of the same curved pipe. 1... Machine frame, 2... Cylindrical outer frame, 5, 6... Annular end plate, 8... Cylindrical core, 10... Chevron-shaped upper end, 1
5... Fresh concrete.

Claims (1)

[Scope of Claims] 1. A cylindrical outer frame 2 bent in an arc shape is supported on the machine frame 1, annular end plates 5 and 6 are supported at the upper and lower ends of the outer frame 2, and the end plate at the lower end The chevron-shaped upper end 10 of the cylindrical core 8 curved in an arc shape is inserted into the opening of the cylindrical core 5, and the ready-mixed concrete 15 is put between the core 8 and the outer frame 2, and the ready-mixed concrete 15 is vibrated. While applying the same pressure, the chevron-shaped upper end 10 of the core 8 is raised in an arc shape to the outside of the opening of the annular end plate 6 at the upper end of the outer frame 2, and after the concrete 15 is semi-hardened, the core 8 is raised in an arc shape. A method for manufacturing bent concrete pipes characterized by moving them in a shape and removing them from the mold. 2. The concrete bent pipe manufacturing method according to claim 1, wherein the outer frame 2 and the core 8 are supported concentrically.