JPS592390Y2 - Union for resin tube connection - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a union connected to a resin tube.

For example, when a resin tube with a vacuum passage formed inside is press-fitted into a union such as a vacuum check valve, the tube relaxes when the surrounding temperature becomes high, and the reaction force upon press-fitting is reduced.

In conventional unions, a protrusion with a perfectly circular cross section fits into the tube to seal and maintain the connection, so when the reaction force becomes small, the tube rotates relative to the union due to external force such as vibration, reducing the sealing force. There is a risk that the union may decline or break away from the union.

Therefore, the purpose of the present invention is to provide a union that eliminates the above-mentioned drawbacks, and its gist is that the conventional protrusion has a perfectly circular cross section and that a part of this protrusion is removed. At least one other protrusion having a hollow shape is provided on the outer periphery of the union, thereby making it difficult for the tube to rotate and ensuring sealing performance.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 10 denotes a Duracon valve body with a built-in check valve, one end of which communicates with a negative pressure source (not shown), and the other end of which is integrally formed with a union 11.

12 is a tube made of nylon resin, one end of which is fitted into the union 11, and the other end is connected to a brake booster (not shown).

To explain in detail the connection between the union 11 and the tube 12, there are three protrusions 13° 14.15 on the union 11.
As is clear from FIG. 2, the protrusion 13 closest to the check valve body 10 has a non-circular cross section.

That is, the protrusion 13 has four land portions 16 spaced apart from each other, allowing the shoulder 16a and the tube 12 to fit together.

Therefore, rotation of the tube 12 is prevented, while the protrusion 1
4.15 has a circular cross section as shown in the third figure, and sealing performance with the tube 12 is ensured.

FIG. 4 shows an example in which three land portions 26 are provided, which provides the same effect as the land portion 16 in FIG. 2.

In FIG. 5, the land portion 36 is formed in a semicircular shape, and in FIG. 6, each side portion 46 is formed flat, and the tube 12 is
This is to stop the rotation.

In addition to what is shown in the drawings, the cross-sectional shape of the protrusion 13 may be square or star-shaped.

In addition, the non-circular protrusion 13 is connected to the check valve body 10.
By installing it on the side, that is, by providing it at a position far from the tip of the union 11, it becomes easier to insert the tube 12 into the union 11.

[Brief explanation of drawings]

Fig. 1 is a diagram showing how the union and tube of the present invention are fitted, Fig. 2 is a sectional view taken along the line A-A in Fig. 1, Fig. 3 is a sectional view taken along the line B-B in Fig. 1, and Fig. 4 is a sectional view taken along the line A-A in Fig. 1. -FIG. 6 is a sectional view similar to FIG. 2, but shows a modified example. 11...Union, 13.14.15...
··protrusion.

Claims (1)

[Scope of utility model registration request] In a hollow cylindrical union into which the end of a resin tube is press-fitted into the outer periphery, at least one projection having a perfect circular cross section perpendicular to the axis of the union and concentric with the union is provided on the outer periphery, A union characterized in that at least one protrusion formed by removing a portion of the protrusion is provided on the outer periphery.