Patent ID: 7628171

Claim:
A leak preventing structure comprising: a first unit including (i) a first casing, (ii) a convex portion provided for the first casing, and (iii) a first passage which is open in an end of the convex portion; a second unit including (i) a second casing, (ii) a concave portion which is provided for the second casing, the concave portion includes an inner circumferential wall and a bottom wall and into which the convex portion is to be inserted, and (iii) a second passage which is open in the bottom wall of the concave portion and which is connected to the first passage and permits a fluid to flow between the first and second passages, when the convex portion is inserted into the concave portion; and an absorbing member provided on the inner circumferential wall of the concave portion and interposed between the inner circumferential wall of the concave portion and an outer circumferential surface of the convex portion, the absorbing member, being an elastic member including an opening which is smaller than outer size of the convex portion and into which the convex portion is to be inserted, is configured to absorb the fluid when the convex portion is pulled out of the concave portion.