JPS5837890B2 - Surface treatment method for plastic tubes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for surface treatment of plastic tubes.

Conventional. When making a pressure hose by applying a reinforcing layer around a plastic tube with a smooth surface such as a nylon tube, it is difficult for adhesives to adhere to the smooth surface of the plastic tube, so the reinforcing layer applied to the surface Since there is a risk of peeling and deterioration of performance, the smooth surface of such plastic tubes is roughened to improve adhesive bonding by the following method.

■ As shown in Fig. 1, the tube T is passed through the flame of the annular burner B, and while its surface is heated and softened by the flame, the tube T is passed between the molded roller R, which has an uneven surface, due to the unevenness of this roller. An uneven surface is formed on the surface of the tube.

■ As shown in Fig. 2, a plurality of rollers R1 with rollers on their surfaces are rotatably supported on a rotating frame W with a tube T passing between them, and while rotating this frame W, A tube T heated and softened by an annular burner similar to that shown in FIG. 1 is passed between the rollers R, and a knurled rough surface is formed on the tube surface by pressure from the rollers.

■ As shown in Fig. 3, countless needles N are planted and fixed on the inner periphery of the annular support M, and the tube T is passed through the center of the annular support M and countless small grooves are created by scratching the tube surface with the tip of the needle N. Forms a rough surface.

However, the method (2) causes deterioration of the tube even if only slightly, and there is a risk that the diameter of the tube may be deformed due to pressure from the rollers.

In addition, method (■) tends to leave deep striations on the tube surface, and requires a strong tensile force, which may cause elongation deformation.Furthermore, since the striations are only in the axial direction of the tube, it has no effect on strengthening the adhesion. Not enough.

The present invention is designed to eliminate the above-mentioned drawbacks. A pair of upper and lower endless sandpapers are provided in parallel using guide rolls, and a plastic tube is passed between the upper and lower endless sandpapers in parallel with the guide roll. Tension rolls are provided at positions corresponding to both sides of the tube to press the endless sandpaper against the upper and lower circular surfaces, and at the same time, the endless sandpaper is circulated in the circumferential direction of the tube and the tube is moved in the axial direction. As a result, the surface of the tube is characterized by a combination of grooves in the circumferential direction and the axial direction, and as described above, the desired purpose can be successfully achieved.

Hereinafter, an embodiment of the present invention shown in FIG. 4 will be explained. An endless sandpaper 1 is circulated by guide rolls 2 and 3. A pair of upper and lower endless sandpapers are provided parallel to each other, and the rolls are rolled between them. Tension rolls 4 and 5 are placed at positions corresponding to both sides of the tube P so as to pass the plastic tube P in parallel with the tubes 2 and 3, and to press the endless sandpaper 1 and 1 against the upper and lower surfaces of the tube P. are provided, and while the upper and lower endless sandpapers 1 are circulated in the directions of arrows ¥1 and ¥2, respectively, the tube P is moved in the direction of arrow Y3.

In this way, the endless sandpaper circulates in opposite directions, enclosing the tube in between, which not only eliminates the risk of the tube escaping, but also prevents the formation of streaks on most of the circumference of the tube. obtain.

In addition, since the endless sandpaper circulates, there is little resistance to the direction of the tube's tensile force, allowing work to be carried out smoothly and reliably.

The present invention provides a surface treatment method for a plastic tube, in which a pair of upper and lower endless sandpapers are provided in parallel using guide rolls, a plastic tube is passed between the upper and lower endless sandpapers in parallel to the guide rolls, and the endless sandpaper is applied to the tube. Since the tube is circulated circumferentially, there is no need to heat or compress the tube as in the past.

In addition, in the processing method according to the present invention, tension rolls are provided at positions corresponding to both sides of the tube in order to press the endless sandpaper against the upper and lower surfaces of the tube, so there is no risk of damaging the tube or causing a change in diameter as in the conventional method. There is no.

In addition, since the rough surface P' formed on the surface of the tube P is composed of aligned grooves in the axial direction and the circumferential direction, the adhesive bonding with the adhesive is extremely good.

Therefore, the present invention is suitably effective in manufacturing nylon hoses and the like.

[Brief explanation of the drawing]

FIGS. 1 to 3 are perspective views showing each conventional rough surface shape method, and FIG. 4 is a perspective view showing an embodiment of the present invention. 1 is sandpaper, 2 and 3 are guide rolls, 4 and 5 are tension rolls, P is a plastic tube, and P' is a rough surface.

Claims (1)

[Claims] 1 A pair of upper and lower endless sandpapers are arranged parallel to each other by guide rolls, a plastic tube is passed between the upper and lower endless sandpapers in parallel to the guide rolls, and the plastic tube is inserted in order to press the endless sandpaper against the upper and lower surfaces of the tube. Tension rolls are provided at corresponding positions on both sides of the tube, and the endless sandpaper is circulated in the circumferential direction of the plastic tube, and at the same time, the plastic tube is moved in the axial direction, so that the surface of the plastic tube is coated in a circumferential manner. A method for surface treatment of a plastic tube, characterized by producing striations in both direction and axial direction.