JP3050682B2 - Synthetic resin hose and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a synthetic resin hose and a method for producing the same.

[0002]

2. Description of the Related Art Thermoplastic hollow bodies, such as hoses and ducts, are used in various applications. For example, ducts are used in intake systems of automobile engines and the like. In such a hollow body, conflicting properties are required. That is, the hollow body is required to have high mechanical strength in order to maintain a hollow shape on the half surface where flexibility is required.

[0003] As a method of manufacturing such a hollow body, Japanese Patent Application Laid-Open No. 3-26522 discloses a hard resin made by applying an adhesive containing metal powder to a joining surface in a mold provided with an electromagnetic induction coil. A method is disclosed in which a reinforcing material is provided, a parison formed of a soft resin is housed in a molding die, blow-molded, a high-frequency current is applied to an electromagnetic induction coil, and the reinforcing material is joined and integrated. I have.

However, in this method, since the hollow body is manufactured by blow molding, the dimensional accuracy of the inner surface of the obtained hollow body is reduced. Also, on the inner surface of the semi-cylindrical reinforcing material in the lower mold,
Since the soft resin parison is housed, the other half-cylindrical reinforcing material is housed in the upper mold and blow-molded,
On the inner surface of the obtained hollow body, a step is likely to occur at locations corresponding to both ends in the axial direction of the reinforcing material. Therefore, the inner surface smoothness of the hollow body is reduced.

Further, since the other reinforcing member is easily dropped from the upper mold, positioning of the reinforcing member disposed on the upper mold becomes complicated, and
The productivity of the hollow body decreases. In particular, when the hollow reinforcing material is formed at a plurality of locations, workability and productivity are significantly reduced.

It is therefore an object of the present invention has excellent flexibility and combines the mechanical strength, be composed of a hard resin part and a soft resin part, Ho made excellent synthetic resin on the inner surface dimensional accuracy
It is to provide a nest.

Another object of the present invention is to provide a method for producing a synthetic resin hose having the above-mentioned excellent characteristics.

In order to achieve the above object, the present inventors have:
Focusing on the fact that a hose having high dimensional accuracy can be obtained by the injection molding method, the present inventors have made extensive studies and completed the present invention.

That is, the present invention provides two-dimensional or three-dimensional
And the hard resin portion formed in the circumferential direction and the soft resin portion formed in the circumferential direction are at least the
Injection molding of a plurality of axially divided hoses integrally formed alternately in the axial direction on the inner surface
It is formed by, providing a circumferential synthetic resin hose formed by fusing integrated joining end face of the dividing member. Ma
And one even without less of the soft resin portion, forming a bellows portion
May be.

[0010] The present invention also discloses a method of manufacturing the hose . This method can be curved in two or three dimensions.
The hard resin part formed in the circumferential direction and the circumferential direction
At least the inner surface of smell and the soft resin portion formed in the
A method of manufacturing a hose which is formed integrally with the alternately axially Te, a plurality of divided members obtained by dividing the hose in the axial direction is molded by injection molding, the circumferential direction of the joining ends of the plurality of divided members <br /> A surface is made of a synthetic resin hose to be fused.

Hereinafter, the present invention will be described in detail.

FIG. 1 is a schematic perspective view showing an example of the synthetic resin hose of the present invention, and FIG. 2 is a schematic perspective view showing a manufacturing process of the hose shown in FIG.

As shown in FIG. 1, the synthetic resin hose 1 has a three-dimensionally curved shape, a smooth cylindrical inner peripheral surface, and a hard resin portion 2 formed in the circumferential direction. And a soft resin portion 3. The hard resin portions 2 and the soft resin portions 3 are formed alternately in the axial direction of the hose 1.

In such a hose 1, high mechanical strength, rigidity and toughness can be imparted to the hose 1 by the hard resin portion 2, and high flexibility and the like can be imparted to the hose 1 by the soft resin portion 3. it can. Therefore, the hose 1 is excellent in both mechanical properties and flexibility. Further, enhanced vibration absorbability by soft resinous portion 3, it is possible to increase the耐負-pressure by hard resin portion 2, since the inner peripheral surface is smooth, high internal surface dimensional accuracy, through the hollow portion of the hose 1 The flow resistance of the fluid can be reduced. Furthermore, in the case where the hard resin portion 2 is formed at the end of the hose 1, it is possible to enhance the fitting property and fitting property to the connection device.

Further, since the mechanical strength can be ensured even when the thickness of the hard resin portion 2 is reduced, the weight can be reduced. Further, the hard resin portion 2 and the soft resin portion 3 formed in the circumferential direction of the hose 1 can be easily separated and recycled.

As shown in FIG. 2, such a hose 1 has a semi-cylindrical cross-section curved member 1 divided into two in the axial direction.
It can be manufactured by heat-sealing the circumferential end surfaces of a and 1b. That is, the hard resin portion 2 and the soft resin portion 3
Each of the curved members 1a and 1b formed as described above is formed by a two-layer injection molding method. When the curved members 1a and 1b are molded by the injection molding method, a molded product having higher dimensional accuracy including the inner peripheral surface can be obtained than by the blow molding method. Further, with the injection molding, the hard resin portion 2 and the soft resin portion 3 are joined and integrated.

Further, when the circumferential end surfaces of the curved section members 1a and 1b are integrally joined by heat fusion, the hose 1 having a smooth inner peripheral surface is obtained. That is, the sectional curved member 1
a, hard resin portion 2 having high mechanical strength in the circumferential direction
Is formed, so that the cross-section curved member 1 is
a, 1b, even if pressure is applied to the joining end face.
Does not melt and swell inward of the hose 1.

The hose is tertiary as in the above embodiment.
The shape is not limited to the original shape, and may be two- dimensionally curved. Also,
If necessary, at least one of the hard resin part and the soft resin part, preferably the soft resin part, may have a bellows shape.

FIG. 3 is a schematic sectional view showing another example of the synthetic resin hose of the present invention, and FIG. 4 is a schematic sectional view showing a manufacturing process of the hose shown in FIG.

In this example, a two-dimensionally curved hose 1
1 is shown. The hose 11 has a hard resin portion 12 and a bellows-shaped soft resin portion 13 formed in the circumferential direction, respectively.
a and the other soft resin portion 13b, and can be manufactured by heat-sealing the circumferential end surfaces of the semi-cylindrical cross-section curved members 11a and 11b divided into two in the axial direction in the same manner as described above.

In such a synthetic resin hose 11, the soft resin portions 13b are formed at both ends, so that the sealing property at the connection portion can be ensured, and the soft resin portion 13a has a bellows shape, so that flexibility is improved. Can be even higher. Also ,
The snake abdomen it is possible to further improve the vibration absorption.

When the end faces of a plurality of cross-sectionally curved members having a soft resin portion formed on at least one end thereof are fused, an inner surface regulating core corresponding to the inner diameter of the hose is inserted into the end and heat fusion is performed. It is preferred to wear. In this case, the inner surface smoothness of the injection-molded cross-section curved member is maintained, and the sealing property at the connection portion by fusion is further improved.

The type of the hard resin and the soft resin is not particularly limited. Examples of the hard resin include styrene-based polymers, polycarbonates, polypropylenes, and hard thermoplastic elastomers (for example, styrene-based elastomers, olefin-based elastomers, and the like). Hard and tough resins such as polyester-based elastomers) are exemplified. As soft resins, styrene-based, olefin-based, and polyester-based thermoplastic elastomers are exemplified.

The width between the hard resin portion and the soft resin portion is
It can be selected appropriately according to the application of the hose . The hard resin portion and the soft resin portion may be formed integrally in the circumferential direction of the hose , and each of the resin portions may be formed in a spiral shape. Furthermore, at least one of the hard resin portion and the soft resin portion may be formed in the circumferential direction of the hose . FIG. 5 is a sectional perspective view of a main part showing still another example of the hose of the present invention.

In this example, a thin hard resin portion 22 is formed on the inner surface side of the synthetic resin hose 21 in the circumferential direction, and a soft resin portion 23 is integrally formed between the hard resin portions 22. And covers the outer surface of the hard resin portion 22.

Even with the hose 21 having such a structure,
The hard resin portion 22 can secure mechanical strength, rigidity and toughness.

The hose does not need to be formed by two curved section members, but may be formed by a plurality of curved section members divided in the axial direction of the hose . In addition, ho
Over scan sectional shape is not limited to a cylindrical shape, a polygonal shape, may be an elliptical shape. Further, the plurality of divided members divided in the axial direction only need to correspond to the shape of the hose as a whole. To increase the productivity, although preferred Ho
Scan is formed by divided members divided into two in the axial direction.

The divided member can be manufactured by a method in which a hard resin portion is first molded using a hard resin and a soft resin, and then the soft resin portion is secondarily molded, and the two are integrally molded. Contrary to the above, the soft resin portion may be formed by primary molding and the hard resin portion may be formed by secondary molding, or both the soft resin and the hard resin may be simultaneously injected and molded.

The circumferential joint end face of the dividing member, various welding methods, for example, hot plate fusing, by a method such as vibration welding or ultrasonic welding, can be joined integrally fused.

The joining end face of the divided member is not limited to a flat shape,
It can be formed into various shapes. FIG. 6 is a sectional view showing another example of the dividing member.

In this example, crimping margins 32a and 32b having an L-shaped cross section are formed on the side portions adjacent to the end surfaces of the cross-sectional curved members 31a and 31b as the dividing members. By providing such crimping allowances 32a and 32b, the crimping work of the joint end face including the positioning is facilitated. After the crimping margins 32a and 32b are joined and integrated by fusion,
It may be removed as needed.

The crimping allowance is not limited to the L-shape, but may be formed in a suitable shape such as a plate. In addition, the crimping allowance can be formed at an appropriate location, for example, may be continuous along the axial direction of the cross-section curved member, or may be formed at predetermined intervals.

FIGS. 7 and 8 are sectional views showing still another example of the dividing member.

In the example shown in FIG. 7, concave / convex portions 42a and 42b that can be fitted to each other are formed on the end surfaces of the cross-sectional curved members 41a and 41b as the dividing members. In the example shown in FIG. 8, the end surfaces of the cross-sectional curved members 51a and 51b are each edged, and inclined surfaces 52a and 52b that are in surface contact with each other are formed.

Such bending members 41a, 41b, 51
In a and 51b, the positioning of the joining end face can be reliably performed, and the contact area of the joining end face can be increased, so that uniform joining properties can be secured.

The joining end face is not limited to the shapes shown in FIGS. 7 and 8, and can be formed in various shapes. For example, an uneven portion extending in the axial direction may be formed on an end surface of the curved section member, and a pin-shaped convex portion and a concave portion may be formed at appropriate positions. In addition, the end surfaces of the cross-sectional curved member may have a wedge-shaped cross-sectional shape that comes into surface contact with each other.

The hard resin portion and the soft resin portion may be colored in the same or different colors as required. In the case of using resins colored in different colors, hollow molded articles colored in a plurality of colors can be manufactured.

[0038]

According to the synthetic resin hose of the present invention, at least the circumferentially joined end faces of the plurality of divided members having the hard resin portions formed in the circumferential direction are fused and integrated, so that flexibility and mechanical strength are improved. In addition to having both characteristics of target strength, it has excellent inner surface dimensional accuracy.

According to the method of the present invention, a plurality of divided members having at least the hard resin portion formed in the circumferential direction are produced by injection molding, and the joining end surfaces of the divided members are fused to each other. Synthetic resin hoe with excellent properties
Vinegar can be produced.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an example of a synthetic resin hose of the present invention.

FIG. 2 is a schematic perspective view showing a manufacturing process of the hose shown in FIG.

FIG. 3 is a schematic sectional view showing another example of the synthetic resin hose of the present invention.

FIG. 4 is a schematic sectional view showing a manufacturing process of the hose shown in FIG.

FIG. 5 is a cross-sectional perspective view of a main part showing still another example of the hose of the present invention.

FIG. 6 is a cross-sectional view showing another example of the dividing member.

FIG. 7 is a cross-sectional view showing still another example of the dividing member.

FIG. 8 is a sectional view showing still another example of the dividing member.

[Explanation of symbols]

1, 11, 21 ... synthetic resin hoses 1a, 1b, 11a, 11b, 31a, 31b, 41
a, 41b, 51a, 51b: Curved cross section member 2, 12, 22: Hard resin part 3, 13a, 13b, 23: Soft resin part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29D 23/00 B29C 45/16 B29C 65/02 B29C 69/02

Claims (3)

(57) [Claims] 1. A two-dimensional or three-dimensional curved shape
Both are formed in the circumferential direction with the hard resin part formed in the circumferential direction.
Axially soft resin portion and at least the inner surface thereof which
Alternately a hose formed integrally with, a plurality of divided members divided in the axial direction is formed by injection molding, wherein
Circumferential <br/> synthetic resin hose formed by fusing integrated joining end face of the dividing member. 2. The method according to claim 1, wherein at least one of the soft resin portions has a bellows portion.
2. The synthetic resin hose according to claim 1, wherein the hose is formed of a synthetic resin hose. 3. When it is curved two-dimensionally or three-dimensionally.
Both are formed in the circumferential direction with the hard resin part formed in the circumferential direction.
Axially soft resin portion and at least the inner surface thereof which
Alternately method of manufacturing a hose which is formed integrally with,
A method of manufacturing a synthetic resin hose in which a plurality of divided members obtained by dividing a hose in an axial direction are formed by injection molding, and a joining end face in a circumferential direction of the plurality of divided members is fused.