JPS6122104Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a shaft, and more specifically, to a shaft in which both the inner and outer surfaces of a metal cylinder are coated with synthetic resin.

Conventionally, this type of cylindrical rain gutter made of metal coated with synthetic resin on both the inside and outside has been constructed by using a steel plate 9 coated with synthetic resin 8 on both sides at both ends in the width direction, as shown in Fig. 1. There is a product that is bent into a cylindrical shape so that it can be joined by processing, but in this case, the steel plate 9 is four-fold at the seam processing part X, so it is difficult to cut it with scissors. Also, there was a problem that the tensile strength at the ribbed portion X was low.

The present invention has been developed in view of the above points, and its main purpose is to provide a vertical passageway that can prevent the metal cylinders from opening and has high bonding strength at the joints of the metal cylinders. .

The present invention will be explained in detail below based on embodiments shown in the figures. The vertical passage according to the present invention has a metal tube 1 formed by bending a metal band plate into a cylindrical shape, and an inner layer 2 of synthetic resin covering the entire surface is coated on the inner peripheral surface of the metal tube 1.
The outer circumferential surface of the metal cylinder 1 is coated with an outer layer 4 of synthetic resin over the entire surface of the metal wire 3 wound spirally around the outer circumference of the metal tube 1. The metal tube 1 abuts both ends of the metal strip in the width direction,
Or, it is formed by overlapping, and the fourth
As shown in the figure, a metal strip 5 unraveled from a coil 10 is passed through a forming roll 11 to form it into a cylindrical shape to continuously produce a metal cylinder 1.
The metal wire 3 is spirally wound around the outer circumference of the metal tube 1 by the winding device 12, and the first mold 13 is placed inside the metal tube 1 and the second mold 13 is placed outside the metal tube 1.
Synthetic resin such as vinyl chloride is extruded from the mold 14 onto both the inner and outer surfaces of the metal cylinder 1, so that the inner and outer layers 4 of the synthetic resin are formed over the entire surface of the metal cylinder 1.
The metal cylinder 1 and the metal wire 3 were embedded in the synthetic resin. The above winding device 12
consists of a drum 15 that rotates around a central axis that coincides with the feeding direction of the metal tube 1 and a plurality of bobbins 16 provided on the outer periphery of the drum 15. Therefore,
The metal wire 3 wound around each bobbin 16 is helically wound around the outer periphery of the metal tube 1 that is sequentially conveyed in the axial direction, and the metal tube 1 immediately after being formed into a cylindrical shape by the forming rolls 11 is about to open. metal wire 3
While the metal cylinder 1 is tied up, both the inside and outside surfaces are coated with synthetic resin, and the number of metal wires 3 can be changed as necessary.

As described above, in the present invention, an inner layer of synthetic resin is coated on the entire inner peripheral surface of a metal cylinder obtained by bending a metal band plate into a cylindrical shape, and the inner layer of synthetic resin is applied to the outer circumference of the metal cylinder in a spiral shape. Since the outer circumferential surface of the metal tube is coated with an outer layer of synthetic resin over the entire surface of the metal wire being wound, the metal wire prevents the metal tube from opening from the joint, and prevents the metal tube from expanding. Therefore, the bond between the inner and outer layers and the metal tube is strong, and even though the metal tube is formed by bending a metal strip, the metal tube is This has the advantage of increasing the bonding strength between both the inner and outer layers at the joint.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional example, Fig. 2 is a sectional view showing an embodiment of the present invention, Fig. 3 is a partially cutaway perspective view of the same, and Fig. 4 is a schematic diagram showing the manufacturing process of the same. , FIG. 5 is a schematic cross-sectional view taken along the line AA in FIG. 4, in which 1 is a metal tube, 2 is an inner layer, 3 is a metal wire, and 4 is an outer layer.

Claims (1)

[Scope of utility model registration request] A metal tube is formed by bending a metal strip into a cylindrical shape, and an inner layer of synthetic resin is applied to the entire surface of the inner circumferential surface of the metal tube, and a metal wire is wound spirally around the outer circumference of the metal tube. A vertical shaft with a synthetic resin outer layer covering the entire surface of the metal tube from above.