JPH0620786B2 - Method of manufacturing uneven hose - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing an uneven hose.

More specifically, an improvement in product finishing accuracy of a method for manufacturing a concavo-convex hose in which thick and thin parts are alternately formed in the length direction and a concavo-convex shape formed by the thick and thin parts is formed on the outer peripheral surface. Regarding

[Prior Art] The applicant of the present invention has previously proposed this type of uneven hose (see, for example, No. 3), the effect of reinforcement by the thick portion and the hose length and hose due to the uneven shape of the thick and thin portions. It has features in the measuring function such as the installation length.

Conventionally, as a means for manufacturing such an uneven hose,
It is practiced to use an extruder. That is, the thick and thin portions are formed by alternately changing the extrusion amount of the resin by changing the rotation speed of the extrusion molding machine.

[Problems to be Solved by the Invention] In the above-described conventional method for manufacturing a concavo-convex hose,
When changing the formation of the thin portion, the extrusion amount of the resin cannot be adjusted sensitively by the extrusion molding machine.
There is a problem in that the unevenness is not formed clearly because the steps of the thin portion become gradual, and the product finishing accuracy becomes poor.

The present invention has been made to solve such a problem, and an object thereof is to provide a method for manufacturing a concavo-convex hose having a good product finishing accuracy regarding the concavo-convex shape due to the thick portion and the thin portion. .

[Means for Solving the Problems] In order to achieve the above-mentioned object, in the method for manufacturing a concavo-convex hose according to the present invention, thick and thin portions are alternately formed in the long direction, and thick and thin portions are formed. The uneven hose is formed on the outer peripheral surface of the hose by an extrusion molding machine, and a mold is attached to the outer circumference of the hose raw material extruded to a uniform wall thickness and injected into the mold. While injection molding the additional thickness material with a molding machine, remove the mold, and form the additional thickness material on the outer circumference of the hose raw material to form a thick portion,
This thick portion is formed on the extruded hose raw material at regular intervals, and means for thinning the portion where the thick portion is not formed is adopted.

[Operation] According to the above-described means, a die is attached to the outer periphery of the hose raw material formed to have a uniform thickness by the extrusion molding machine, and the additional thickness material is laminated by injection molding to form a thick portion. From the characteristics of injection molding, it is possible to form an accurate thick part corresponding to the shape of the mold, and in combination with the fact that the part where the thick part is not formed is a thin part, the step difference between the thick part and the thin part Since it becomes clear and the uneven shape can be clearly formed, the object of the present invention is to provide a method for manufacturing an uneven hose having good product finishing accuracy with respect to the uneven shapes of the thick portion and the thin portion.

[Embodiment] An embodiment of a method for manufacturing a concavo-convex hose according to the present invention will be described below with reference to the drawings.

An example of an apparatus in which this embodiment is implemented has a configuration in which an injection molding machine 2 and a mold 3 are installed near a die 11 of a normal extrusion molding machine 1.

The extrusion molding machine 1 includes a die 11 and a material supply unit 12, and a plurality of spiral reinforcements 42 are wound on the outer side of an inner tube 41 in both forward and reverse directions. The material 5 supplied from the part 12 is die 11
Is melt-extruded from the outer tube 43 to form a laminate,
Inner tube 41, reinforcing material 42, outer tube 43
The hose raw material 4 having a three-layer structure and having a uniform thickness is extruded and molded.

The injection molding machine 2 has a cylindrical body 22 having an injection nozzle 21 at its tip.
The screen 24 is equipped with a screen 24 connected to the piston 23, and the wall thickness adding material 6 is charged from the hopper 25 communicating with the inside of the tubular body 2 and melted and injected from the injection nozzle 21.

The mold 3 has a U-shaped cross section, and the U-shaped open portion faces the outer circumference of the hose raw material 3 and can be attached and detached. The mold 3 is connected to the injection nozzle 21 of the injection molding machine 2.

According to such a device example, the hose raw material 4 having a uniform wall thickness is extruded by the extrusion molding machine 1, the die 3 is mounted on the outer periphery of the extruded hose raw material 4, and the hose raw material 4 is injected into the die 3. Molding machine 2
Thus, the operation of detaching the mold 3 is performed after the injection molding of the additional wall thickness material 6.

As a result, the additional wall thickness material 6 is laminated on the outer periphery of the hose raw material 4 to form the thick portion A.

Further, by forming the thick portion A on the extruded hose raw material 4 at regular intervals, it is possible to form a portion where the thick portion A is not formed and to make the thin portion B with a large thickness. it can.

In such an operation, in order to further improve the features such as the reinforcing effect due to the thick portion A in the manufactured uneven hose and the measuring function such as the hose length due to the uneven shape of the thick portion A and the thin portion B, the hose arrangement length, etc. The material and color of the additional wall thickness material 6 can be changed with respect to the hose raw material 4.

In the operation of the above-mentioned device example, since the hose raw material 4 is continuously extruded from the extruder 1, mounting of the mold 3, injection of the thickness adding material 6 of the injection molding machine 2, Type 3
It is required that the extruder 1 be temporarily stopped or the injection molding machine 2 and the mold 3 be made to follow the extrusion movement of the hose raw material 4 during the attachment and detachment.

According to such an embodiment, since the injection molding has a feature that it is possible to form a fine uneven shape, the mold 3
It is possible to form an accurate thick part A corresponding to the shape of
Coupled with the fact that the portion where the thick portion A is not formed is the thin portion B, the step between the thick portion A and the thin portion B becomes clear, and the concavo-convex shape can be formed clearly. In addition, in the injection molding, since the additional thickness material 6 can be precisely injected into the mold 3, the leakage loss of the additional thickness material 6 can be prevented.
Material costs for hose manufacture are reduced.

As described above, in addition to the illustrated embodiment, the hose raw material 3 can be an embodiment having a single layer structure.

Further, the injection molding machine 2 and the mold 3 may be incorporated around the die 11 of the extrusion molding machine or installed in a completely different position from the extrusion molding machine 1.

[Effects of the Invention] As described above, in the method for manufacturing a concavo-convex hose according to the present invention, it is possible to form an accurate thick portion corresponding to the shape of the mold by injection molding, and a portion where the thick portion is not formed is a thin portion. In addition to the above, the step difference between the thick portion and the thin portion can be made clear and the uneven shape can be clearly formed, so that the product finishing accuracy of the uneven shape of the thick portion and the thin portion becomes good. There is.
Also, due to this effect, the manufactured uneven hose can effectively exhibit the reinforcing effect by the thick part, which is its characteristic, and the measuring function such as the hose length and the hose disposition length due to the uneven shape of the thick part and the thin part. it can.

Furthermore, since the thick part is formed by injection molding separately from the extrusion molding of the hose raw material, the material and color of the thick part can be changed, so the reinforcing effect and thickness of the thick part in the manufactured uneven hose can be improved. There is an effect that it is possible to improve the features such as the measuring function such as the hose length and the hose arrangement length due to the uneven shape of the thin part and the thin part.

Furthermore, since the thick portion is formed by injection molding which is a precise quantitative injection, there is an effect that leakage loss of the additional material for wall thickness is prevented and the material cost for manufacturing the hose is reduced.

[Brief description of drawings]

The drawing is a cross-sectional view showing an example of an apparatus for carrying out the embodiment of the method for manufacturing an uneven hose according to the present invention. 1 ... Extrusion molding machine 2 ... Injection molding machine 3 ... Mold 6 ... Additional material for wall thickness A ... Thick part B ... Thin part

Claims (1)

[Claims] Claims: 1. An extrusion hose for producing a concavo-convex hose in which thick and thin parts are alternately formed in the longitudinal direction, and the concavo-convex shape formed by the thick and thin parts is formed on the outer peripheral surface. A hose raw material extruded to a uniform wall thickness by a machine is fitted with a mold, and an additional wall thickness material is injection-molded in the mold by an injection molding machine, and then the mold is removed A thick part is formed by stacking additional thickness material on the outer periphery of
A method for manufacturing a concave-convex hose in which the thick portion is formed on the extruded hose raw material at regular intervals and the portion where the thick portion is not formed is a thin portion.