Connection structure of multi-channel tube with branching tube and connection method therefor
A connection structure of a multi-channel tube with branching tubes is provided with a multi-channel tube having an end, the multi-channel tube including; an outer tube; a partition being formed in a unitary body and running parallel with the outer tube, the partition partitioning an interior of the outer tube into two or more channel holes; and a passage formed at an end of the partition, the passage linking the channel holes; two or more branching tubes respectively inserted into the channel holes to an insertion depth greater than a depth of the passage measured from the end of the multi-channel tube; and brazing material spreading beyond the passage over clearances between the multi-channel tube and the branching tubes and connecting the multi-channel tube and the branching tubes.
1. A connection structure of a multi-channel tube with branching tubes, the connection structure comprising:
a multi-channel tube having an end, the multi-channel tube including;
an outer tube;
a partition being formed in a unitary body and running parallel with the outer tube, the partition partitioning an interior of the outer tube into two or more channel holes; and
a passage formed at an end of the partition, the passage linking the channel holes;
two or more branching tubes respectively inserted into the channel holes to an insertion depth greater than a depth of the passage measured from the end of the multi-channel tube; and
brazing material spreading beyond the passage over clearances between the multi-channel tube and the branching tubes and connecting the multi-channel tube and the branching tubes.
2. The connection structure of claim 1 , wherein the passage is one or more cuts formed by cutting boundaries between the partition and the outer tube.
3. The connection structure of claim 1 , wherein the passage comprises a cut-off end receded from the end of the multi-channel tube.
4. The connection structure of claim 1 , wherein the end of the multi-channel tube is flared to form a flare portion.
5. A connection method for connection of a multi-channel tube with branching tubes, the multi-channel tube having an outer tube and a partition formed in a unitary body and running parallel with the outer tube, the partition partitioning an interior of the outer tube into two or more channel holes, the connection method comprising:
forming a passage at an end of the partition so as to link the channel holes;
flaring a portion of the outer tube, the portion being separated from the partition by the passage;
inserting the branching tubes respectively into the channel holes to an insertion depth greater than a depth of the passage measured from the end of the multi-channel tube; and
brazing the multi-channel tube and the branching tubes.
6. The connection method of claim 5 , wherein the forming step further comprises cutting boundaries between the partition and the outer tube.
7. The connection method of claim 5 , wherein the forming step further comprises cutting off the end of the partition so as to be receded from the end of the multi-channel tube.