| 摘要 |
<p>A blind rivet wherein the remaining mandrel portion is prevented from dropping out and the fastening force thereof is maintained at a high level without causing an increase to mandrel manufacturing cost, assuring uniform pressing of the head against the end surface of the sleeve merely by the operation of pulling in the mandrel, and wherein the fastening is maintained in good order. A mandrel (22) has an anti-dropping-off portion (33) that is formed between a head (29) and a breakable portion (31) thereof. In the anti-dropping-off portion (33), a plurality of latching ridges (34) is formed which have peaks that protrude outwardly in the radial direction and frictionally engage with the inner wall surface of a sleeve. The latching ridges are formed in the outer surface of the portion of the mandrel that is between the head and breakable portion thereof, so as to be diagonal relative to the circumferential direction of the outer surface of the mandrel and to cross each other, with the peaks thereof formed in a twill pattern protruding out from the outer surface of that mandrel portion. ( Fig. 2 )</p> |
