Air Bleeding Pipe Joint

Abstract

An air bleeding pipe joint has a pair of connection pipe portions, a branch pipe portion having an air bleeding hole in an inside thereof, a plug body, and an elastic annular sealing member providing an air-tight seal between a female fitting surface of the branch pipe portion and a male fitting surface of the plug body. The plug body is removably mounted to the branch pipe portion in threaded engagement therewith such that a seating surface of the plug body seats on a seated surface of the branch pipe portion. An air discharge path is provided on an upper end of the branch pipe portion and / or the plug body with respect to a sealing position at which the sealing member is disposed for discharging outwardly an air that leaks upwardly through the sealing position.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to an air bleeding pipe joint connected to a circulation pipeline for an engine cooling water and adapted for bleeding an air in the circulation pipeline.[0003]2. Description of Related Art[0004]In a motor vehicle, when an engine cooling water is supplied in a circulation pipeline for the engine cooling water, an air is sometimes confined within the circulation pipeline, and as a result, it is hard to inject the engine cooling water in a radiator. As a countermeasure, an air bleeding portion has been conventionally provided at a part of the circulation pipeline.[0005]For example, Patent document 1 as below discloses a technique of providing such air bleeding portion.[0006]Further, Patent Document 2 as below also discloses such air bleeding portion provided in a circulation pipeline for an engine cooling water. According to the disclosure of Patent Document 2, an air bleeding pipe joint as t...

AI Technical Summary

Benefits of technology

[0034]Thus, according to the present invention, it can be positively detected whether the sealing member is attached in the air bleeding pipe joint, by conducting the air-tightness test.

[0035]As described above, in the past, in order to verify attachment of a sealing member, an air-tightness test is conducted for an air bleeding pipe joint with a plug body being not fully screwed in a branch pipe portion. So, there is a need for adding a step of screwing the plug body completely in the branch pipe portion after the air-tightness test in an assembling procedure or an inspection procedure of the air bleeding pipe joint. According to the present invention, the need for this bothersome step can be eliminated.

[0043]However, when the recessed portion is provided in the seating surface of the overlapping surface and / or the seated surface of the overlapped surface for allowing an air to pass through the recessed portion, it can be prevented that the air bleeding pipe joint without the sealing member happens to meet the test for acceptable air-tightness since an air that leaks through the sealing position is confined internally.

[0044]When the above protruding portion is provided on the seating surface of the overlapping surface and / or the seated surface of the overlapped surface, this protruding portion can produce the same effect as the recessed portion stated above.

[0045]Or, the seating surface and / or the seated surface may be formed into the roughened surface having the irregularities or the protuberances. This configuration also can produce the same effect as the recessed portion stated above.

[0049]The reason is that in the air bleeding pipe joint of the molded resin product, the overlapping surface of the plug body tends to tightly contact with the overlapped surface of the branch pipe portion and an air-tight seal is easily formed between the overlapping surface and the overlapped surface, resulting that a air is easily confined internally by a tightly contact region therebetween.

Problems solved by technology

In a motor vehicle, when an engine cooling water is supplied in a circulation pipeline for the engine cooling water, an air is sometimes confined within the circulation pipeline, and as a result, it is hard to inject the engine cooling water in a radiator.

However, such additional step could be a complicating factor in an assembly of an air bleeding pipe joint or an inspecting procedure of the air bleeding pipe joint.

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