JP2002200397A - Bellows pipe hose for washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bellows pipe hose for a washing machine comprising an inner hose on the inside of a casing and an outer hose on the outside formed reasonably and economically respectively. SOLUTION: Each of a bellows-like inner hose and the bellows-like outer hose has a two-layer structure comprising a polymer A layer and a polymer B layer molded continuously integrally. The polymer A layer of the inner hose is larger in thickness than the polymer B layer, and the polymer B layer of the outer hose is larger in thickness than the polymer A layer. Thermoplastic elastomer is preferably used for the polymer A, and polyolefin preferably used for the polymer B. Constituting materials satisfying the performance required for the inner hose and the outer hose respectively are selected and used to continuously integrally form them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bellows hose for a washing machine. Specifically, the present invention relates to a bellows hose for a washing machine in which an inner hose inside a casing of the washing machine and an outer hose outside the washing machine are configured based on respective required performances.

[0002]

2. Description of the Related Art In a washing machine, since a washing drain is led out of a washing tub through a casing housing a power section and a rotating section to a drain port outside the casing, a flexible hose of a bellows pipe is used as a drain hose. Installed as Conventionally, the bellows tube hose for a washing machine has been used by integrally molding the whole with the same material and shape. However, in general, the parts used in the casing (hereinafter referred to as internal hose)
Is often mounted in a bent state, and
In order to be subjected to severe vibration, a hose having a high level of bending resistance, vibration resistance, and durability must be used. For this purpose, it is necessary to use a high-grade material for the hose, or to increase the thickness of the tube wall and to increase the irregularities forming the bellows. On the other hand, a portion used outside the casing (hereinafter referred to as an external hose) does not require much bending resistance and vibration resistance, and on the other hand, it is desirable that the portion be lightweight, have a small outer diameter and be easy to handle. In particular, in a fully automatic washing machine, the use conditions in the casing are severe, and therefore, improvement in bending resistance and vibration resistance of the internal hose is desired.

[0003]

In order to meet the above-mentioned demand, if an entire bellows tube hose for a washing machine is manufactured integrally with the same performance and shape in accordance with the inner hose under severe use conditions, the handling of the outer hose is improved. Is not only inconvenient,
Increases cost. Also, the inner hose and the outer hose
After individually molding with performance and shape suitable for use conditions, both can be joined and manufactured. But,
The hoses formed and joined separately have problems such as that the joints are easily detached during use and are difficult to handle, the joints are easily damaged and lack durability, and the manufacturing means is complicated and the manufacturing cost is high. These problems can be solved to some extent by molding the inner and outer hoses with different performances together, for example, using a crosshead blow extruder. However, there is a need to complete a bellows tube hose for a washing machine that has performance specialized for the washing machine and that can be produced more efficiently. The present invention was completed as a result of research and trial production, with the object of a bellows tube hose for a washing machine having a reasonable configuration that can withstand the use conditions as an internal hose and an external hose, and which can be economically produced. Things.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a bellows-shaped inner hose mounted in a casing of a washing machine and a bellows-shaped outer hose exposed outside the casing, which are continuously and integrally formed. And the inner hose has a two-layer structure including a layer of polymer A and a layer of polymer B, wherein the thickness of the layer of polymer A is larger than the thickness of the layer of polymer B, and the outer hose is B. A bellows tube hose for a washing machine characterized by having a single-layer structure made of B. Further, according to the present invention, as described above, except that the outer hose has a two-layer structure composed of a layer of polymer A and a layer of polymer B, wherein the thickness of the layer of polymer B is smaller than the thickness of the layer of polymer A. 2. The bellows tube hose for a washing machine according to claim 1, wherein the hose is large.
A thermoplastic elastomer as the polymer A;
Is preferably a polyolefin. Also, a flexible hose in which the difference in diameter between the peak and the valley of the bellows is larger in the portion corresponding to the inner hose than in the portion corresponding to the outer hose,
Suitable for washing machines. Here, polymers A and B include:
A combination of polymers having the same composition but different compositions is also included.

[0005]

Operation and Embodiment The bellows tube hose for a washing machine according to the present invention will be specifically described with reference to the drawings. FIG.
(A) and (b) are schematic diagrams illustrating the cross-section of the tube wall of the bellows hose for a washing machine according to the present invention, and FIG. 2 is an apparatus preferably used for manufacturing the bellows hose for a washing machine of the present invention. FIG. 1 is a cross-sectional view schematically showing a main part of a continuous extrusion blow molding machine as an example.

First, for reference, a bellows tube hose which is a single layer integrated using a single polymer, but which differs in shape and thickness for each predetermined length corresponding to the inner and outer hoses will be described. . Usually, the opposite mold unit 2
2. A continuous extrusion blow molding machine is used, each of which is connected in the form of a crawler belt, forming a pair of dies 21 and 21 '. First, the material constituting the tube wall is extruded from the annular die 23 to form the annular parison 24 continuously. For a parison corresponding to the part 25 forming the inner hose, where it is desired to be thick,
The extrusion speed is increased, and the extrusion speed is reduced so that the parison of the portion 26 forming the outer hose becomes thinner.
The parison is continuously extruded while repeatedly changing the extrusion speed. Each extrusion speed is determined in consideration of the shape, outer diameter, desired wall thickness, etc. of the bellows tube hose. For example, when the unevenness of the bellows is large, the pipe wall becomes thinner than when the bellows is small, so that it is necessary to increase the extrusion speed to make the pipe wall thicker.

[0007] The extruded parison 23 is pressed against the mold unit 22 by the gas blown from the blow holes 27 and formed into a bellows tube. The molds 21 and 21 ′ are a set of a mold unit 22 a for an internal hose and a mold unit 22 b for an external hose having a different shape from the number necessary for forming a desired hose length. Then, the set of mold units is connected and circulated. When the shape of the inner hose is the same as the shape of the outer hose, a common mold unit can be connected. The formed bellows tube 28
Cool, remove continuously and cut the inner and outer hose sections together. The bellows tube hose manufactured by repeating this operation has a desired thickness and inner and outer diameters in the inner hose portion and the outer hose portion, respectively.
Both are formed continuously and integrally. The hose port and the part to be attached to the casing can be integrally formed by connecting a mold unit therefor as required.

Next, in order to meet the strict requirements for a bellows tube hose for a washing machine, an inner hose portion and an outer hose portion provided by the present invention are integrated, and at least two kinds of different polymer A and polymer are provided. B, a bellows tube hose for a washing machine of the present invention having a different tube wall configuration for each part and a method of manufacturing the hose will be described. The difference in the configuration of the tube wall means that, for example, the thickness of each layer constituting the tube wall, the shape of the tube wall, the type of polymer, the composition ratio of the polymer, and the like are different.

According to the present invention, in order to extrude at least two or more kinds of different polymers, a mold unit is connected in a crawler belt shape, and a multi-ring die for extruding a different polymer for each ring is installed. A continuous co-extrusion blow molding machine is used. The extrusion speed of each extruder communicating with each annular die is adjusted to a predetermined speed based on the required thickness of each layer of the hose wall, and if necessary, the traveling speed of the mold is adjusted. The thickness of each layer of the hose tube wall and the overall thickness are set. And a predetermined extrusion length,
That is, for each length corresponding to the inner hose and the outer hose, the extrusion speed of each extruder and / or the traveling speed of the mold are switched to conditions suitable for each part, so that the pipe wall is formed for each predetermined length. A bellows tube hose for a washing machine having a different configuration can be integrally and repeatedly manufactured continuously.

For example, if the above-described molding machine equipped with a two-layered annular die for extruding polymer A on one side and polymer B on the other side is used, the inner hose and the outer hose illustrated in FIG. The thickness of the layer and the layer of polymer B and / or
Alternatively, bellows tubes having a multilayer structure having different tube wall thicknesses can be continuously and integrally formed repeatedly. If there is a problem with the joining, a third polymer may be inserted into the joining portion in a single layer or a multi-layer using a molding machine equipped with a three-layered ring base, and the inner hose and the outer hose may be integrated and manufactured. it can. In addition, if mold units having different shapes are used, flexible hoses having different tube wall shapes for each predetermined length can be integrally and continuously manufactured.

The bellows tube hose for a washing machine illustrated in FIG. 1A, which is a preferred embodiment of the present invention, will be specifically described. A material having excellent vibration resistance and bending resistance, preferably a thermoplastic elastomer, is used as the polymer A, and an inexpensive general-purpose material, preferably polyolefin, is used as the polymer B, and a portion forming the internal hose 11 is extruded. In this case, the polymer A is supplied at a suitable speed up to a predetermined extrusion speed, and at the same time, the extrusion speed of the polymer B is reduced to be lower than the extrusion speed of the polymer A. In the outer hose section 12, the polymer B is fed up to a predetermined extrusion rate,
The polymer A is produced at an extrusion rate of zero. The appropriate speed may be any speed at which the inner hose and the outer hose can be firmly and integrally joined, and differs depending on the type of the polymer, the thickness of the tube wall, and the like. In this way, a bellows hose for a washing machine having the required performance for each part can be provided at low cost.

As shown in FIG. 2B, which is another preferred embodiment of the present invention, for example, 80% of the wall thickness of the inner hose 11 is made of polymer A and 20%.
Is made of polymer B, and conversely, the outer hose portion 12 is made of polymer B with 80% of the wall thickness and 20% of the wall thickness
Is formed as Polymer A, and a bellows hose for a washing machine with reduced cost can be obtained without lowering practical performance.

Further, in a state where each bellows tube is integrated,
It is preferable that each part of the hose be appropriately shaped to withstand the stress applied to each part of the hose, since the performance of the hose is further improved. For example, the internal hose of a fully automatic washing machine has a cycle of 1
It is not unusual to receive a vibration of about 30 mm amplitude at 000 times / min. Therefore, the bellows hose for a washing machine of the present invention is suitable for the drain hose. For example, the pipe wall of the bellows hose for a washing machine, in which the difference in diameter between the peak and the valley of the bellows tube in the portion corresponding to the inner hose is larger than that in the portion corresponding to the outer hose, It is composed of at least two kinds of polymers such as a plastic elastomer and a polyolefin. By increasing the irregularities in the inner hose with a thick thermoplastic elastomer layer and reducing the irregularities in the outer hose with a thick polyolefin layer,
Vibration resistance and bending resistance can be further improved.

[0014]

According to the bellows tube hose for a washing machine of the present invention, the inner hose in the washing machine casing and the outer hose in the exposed portion outside the casing are appropriately selected and used for the constituent materials satisfying the required performance. And has the feature that it can be easily manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view in the axial direction of a bellows tube hose for a washing machine according to the present invention. (A) The inner hose has a two-layer structure (thickness: A polymer layer> B)
(Polymer layer), bellows tube hose for washing machine with single-layer outer hose (b) Double-layer inner hose (thickness: A polymer layer> B)
Polymer layer), external hose (thickness: A polymer layer <B polymer layer), bellows hose for washing machine

FIG. 2 is a cross-sectional view schematically showing an example of a main part of a continuous extrusion blow molding machine used for carrying out the present invention.

[Explanation of symbols]

11: Internal hose 12: External hose A: Material excellent in vibration resistance and bending resistance (Example: thermoplastic elastomer) B: General-purpose material (Example: polyolefin) 21, 21 ': Mold 22: Mold unit ( Subscript a: for internal hose b: for external hose 23: annular die (annular base) 24: parison 25: part forming internal hose 26: part forming external hose 27: blow hole 28: bellows tube

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tetsuya Inakake Tigers Polymer, Co., Ltd., 6th, Tanyo, Kakegawa-shi, Shizuoka Prefecture Inside the Shizuoka Plant (72) Inventor Yoshiro Nakano 2150 Hozoji Temple, Takanezawa-cho, Shioya-gun, Tochigi Prefecture, Thailand 2150 Inside the Tochigi Plant Gars Polymer Co., Ltd. F term (reference) 3B155 AA18 BB05 FC08 GC02 GC10 MA02 4F100 AK01A AK01B AK03B AL09A BA01 BA02 BA44B DA13 GB81 JB16A JL02

Claims (3)

[Claims] 1. A bellows-shaped inner hose mounted inside a casing of a washing machine and a bellows-shaped outer hose exposed outside the casing are integrally formed continuously, and the inner hose is formed of a polymer A layer and a polymer B. A two-layer structure comprising: a polymer A layer having a thickness greater than that of the polymer B; and an outer hose having a single layer structure comprising the polymer B. Bellows hose for machine. 2. The outer hose has a two-layer structure including a layer of a polymer A and a layer of a polymer B, wherein the thickness of the layer of the polymer B is larger than the thickness of the layer of the polymer A. The bellows hose for a washing machine according to claim 1. 3. The bellows hose for a washing machine according to claim 1, wherein the polymer A is a thermoplastic elastomer, and the polymer B is a polyolefin.