| 摘要 |
An improved rotary expansion tool for reaming frustoconical undercuts in the walls of cylindrical holes is disclosed. The tool is comprised of an elongated sheath with a ram disposed in sliding engagement therein. The ram is provided with an enlarged head which is biased away from the open end of the sheath into which the ram is placed. A load bearing collar is disposed around the sheath intermediate the ends for governing the depth of insertion of the tool into a hole being undercut, and the longitudinal placement of the collar along the sheath can be varied in order to select the depth to which the tool is inserted into the hole. A stop ring is circumferentially disposed around the open end of the sheath to provide a stop for limiting the longitudinal progression of the ram into the sheath, and the longitudinal placement of the stop ring can be varied in order to selectively vary the distance the ram can be pushed into the sheath against the bias of the spring. Cutter holding elements are pivotally mounted on the end of the ram opposite the enlarged head, and longitudinal advancement of the ram into the sheath against the bias of the spring expands the cutter holding elements outwardly to a pair of opposing slots through the wall of the sheath.
|
