JPH06285994A - Fusion-bonding method for synthetic resin member - Google Patents

Abstract

PURPOSE:To reduce burrs extended from an outer surface via two stripes of melting margins and to improve reliability of a fusion-bonded part by opposing surfaces to be fusion-bonded of synthetic resin members in a flange state and providing two stripes of parallel ribs at least at one of the surfaces as a melting margin. CONSTITUTION:Flanges 3, 4 are provided at synthetic resin members 1, 2, and two stripes of parallel ribs 7, 8 are provided at one of opposed flat surfaces 5, 6. When it is pressed to be vibrated, burrs also flow to a recess 15 between the ribs 7 and 8, and hence burrs externally extended are reduced. Since fusion- bonded parts are formed in two stripes, reliability of pressure resistance and airtightness is enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration welding method for two synthetic resin members.

[0002]

2. Description of the Related Art In order to weld synthetic resin members to each other by a vibration welding method, the surfaces to be welded of two members are butted against each other and pressurized so that friction heat is generated. For example, in the fuel filter manufacturing method disclosed in Japanese Patent Laid-Open No. 58-74111, a cross-sectional shape of the welded portion as shown in FIG. 8 is disclosed. In this example, two synthetic resin members 4
The flanges 42 and 43 provided with the grooves 44 and 45 are formed in 0 and 41, and the flat butting surfaces 46 and 47 of both are brought into close contact with each other to apply vibration. In this method, there are problems that the welding surface is too wide and the pressure distribution becomes non-uniform to cause defective welding, or the molten burr protrudes into the inner and outer circumferences A and B.

Therefore, like two synthetic resin members 30 and 31 whose cross-sections are shown in FIG. 5, one rib 36 serving as a melting margin is provided at the center of one of the butted flat surfaces 34 and 35 of the flanges 32 and 33. There are two barriers 37a and 37b for preventing melted burrs on the other side ends. In this structure, as shown in FIG. 6, pressure is applied in the direction of arrow W and vibration is applied in the direction of arrow Z to weld. The melt burrs 38a and 38b prevent the outflow by the barriers 37a and 37b, respectively, and the ribs 36 are worn to obtain a welded state as shown in FIG.

[0004]

However, when the synthetic resin members 30 and 31 having the above-mentioned structure are welded, the ribs 36 are melted and worn away, and the melt burrs 38a and 38b are also worn.
Flow out to both sides of the rib 36. The rib 36 has a relatively wide width, a relatively large amount of melted burr is generated, and the outflow direction is limited to these two directions, so that the rib 36 sometimes gets over the barriers 37a and 37b and sticks out, resulting in an unfinished finished shape.

Further, the guarantee of airtightness or liquidtightness of the welded portion is mainly made at the joint portion (melt layer) between the remaining portion of the rib 36 and the flat surface 35, and this portion is the physical property of the synthetic resin material. Is deteriorated, and reliability such as pressure resistance, airtightness, chemical resistance, etc. is deteriorated.

[0006]

A flange having flat surfaces facing each other is provided at a portion to be welded of two synthetic resin members, and two parallel ribs are provided on the flat surfaces to provide a melting margin. Barriers having a height lower than the protruding height of the ribs are provided on both sides of the one flat surface, and vibration is applied while pressing the two members to melt and fuse the two ribs,
This is a welding method in which the generated burr that flows out to the outside is projected and blocked by a barrier.

[0007]

When the synthetic resin member of the present invention is pressed with its flat surfaces facing each other and vibration is applied, the tips of the two ribs generate heat and melt and fuse to the other side. In this case, the melted portion of the rib becomes melted burr, but the outflow direction is the barrier direction on both sides of the flat surface and the relatively concave portion formed between the two ribs. Since the two-row rib has a narrower width than the conventional one-row rib, the amount of melt burr generated per rib is reduced. Since it is also formed in the recessed portion between them, the outward flow of the melted burr is completely blocked by the barrier.

Further, since the welding surface is divided into two narrow ribs, the two members have two welding surfaces. Therefore, even if the property of the member for welding is deteriorated by the fluid flowing in contact with the member, the fusion surface of the rib of the second rib is maintained without contacting the fluid, and thus the pressure resistance and the airtightness are maintained. Reliability or chemical resistance is kept high.

[0009]

Embodiments Embodiments are shown in FIGS. 1, 2 and 3. The members 1 and 2 made of synthetic resin are a body and a cover forming a box body, for example, a closed casing of an oil mist separator forming a part of a blow-by gas recirculation device of an internal combustion engine. Partial cross-sectional views As shown in FIGS. 1, 2 and 3, flanges 3 and 4 are provided on the peripheral edges of the members 1 and 2, and one of the facing flat surfaces 5 and 6 has two strips. Rib 7,
8 is provided, and barriers 9 and 10 are provided on both sides of the other flat surface 6. The height a of the ribs 7 and 8 is larger than the height b of the barriers 9 and 10, and the width c of each of the ribs 7 and 8 is the same as that of the conventional rib 34.
Is about 2/1 of the width d (FIG. 5). In this example, the widths of the flat surfaces 5, 6 of the flanges 3, 4 are the same as those of the conventional flat surface 34 of FIG.
This is the case when the width is equal to 35.

As shown in FIG. 2, when the members 1 and 2 are pressed in the arrow X direction and vibration in the Y direction is applied, frictional heat is generated between the tips of the ribs 7 and 8 and the flat surface 6, and the ribs 7 and 8 are generated. 8 melts from the tip and wears off, and the wear is melted by burrs 11, 12, 1
3 and 14 occur, and the state shown in FIG.
The melted burrs 11 and 14 flow outward toward the inner and outer circumferences of the fusion-bonded surface, but are blocked by the barriers 9 and 10 and do not form a protruding portion. Further, the melted burrs 12 and 13 go to a relative concave portion 15 sandwiched by two ribs 7 and 8 and are accommodated therein.

Comparing the amount of melted burr generated in the example of FIG. 2 with the conventional case of FIG. 6, although the total amount of generated burr is almost equal,
Each of the melt burrs 11, 12, 13, and 14 in each individual direction is approximately 1/2 of the conventional melt burrs 38a or 38b.
Is. In this way, about half of the total amount of melted burr is recessed 15
It is possible to reduce the amount of melted burr that goes outward and to prevent the protrusion to the side surface of the fusion.

When the members 1 and 2 are fusion-bonded to each other to form a hermetically sealed container and a gas is caused to flow to the R side shown in FIG. 3, this gas has an effect on the physical properties of the synthetic resin member. Even if the fusion surface tends to be deteriorated, the ribs 8 do not come into contact with gas, so that reliability such as pressure resistance, airtightness, and chemical resistance is maintained.

FIG. 4 shows a rib structure of another embodiment. The flat surfaces 2 are formed on the flanges 23 and 24 of the synthetic resin members 21 and 22.
5 and 26 are provided with two ribs 27a, 28a and 27b, 28b, respectively, and 27a, 27b and 28 are provided.
a and 28b are opposed to each other, and their tips are rubbed to generate heat. The method of generating heat is shown in FIGS.
This is similar to the case of FIG.

[0014]

According to the welding method of the present invention, the ribs to be melted have two ribs, and the generated molten burrs are distributed in the outward direction and in the recesses between the two ribs. The amount is reduced, and the appearance of burrs on the fused side surface is eliminated.

Further, the function of the fused portion such as pressure resistance, airtightness, chemical resistance, etc. by fusion is guaranteed by the double ribs, and one of them does not come into contact with harmful fluid, so pressure resistance, airtightness, chemical resistance High reliability for sex.

[Brief description of drawings]

FIG. 1 is a diagram showing a cross section of a member structure according to an embodiment.

FIG. 2 is a cross-sectional view showing a welding process of the example.

FIG. 3 is a cross-sectional view showing a state after welding of the example.

FIG. 4 is a view showing a structural cross section of a member of another embodiment.

FIG. 5 is a view showing a cross section of a conventional member structure.

FIG. 6 is a cross-sectional view showing a conventional welding process.

FIG. 7 is a cross-sectional view showing a state after conventional welding.

FIG. 8 is a cross-sectional view of a structural example of another conventional member.

[Explanation of symbols]

 1 and 2 members 3 and 4 flanges 5 and 6 flat surfaces 7 and 8 ribs 9 and 10 barriers 11 and 12, 13 and 14 melt burr

Claims (1)

[Claims] 1. A welding method in which two synthetic resin members are provided with flanges having flat surfaces facing each other, and heat is applied by applying vibration in a facing direction while applying vibration to generate heat. Synthetic resin member characterized in that parallel ribs are provided as a melting allowance, and barriers having a height lower than the protruding height of the ribs are provided on both sides of one flat surface so as to prevent melted flash from protruding. Welding method.