公开(公告)号：US10527531B2

公开(公告)日：2020-01-07

申请号：US15414424

申请日：2017-01-24

Applicant: UNITED STATES GYPSUM COMPANY

Inventor： Robert T. Peddle

IPC: G01N3/303

Abstract: A ball drop iris is provided for use in a ball drop testing apparatus. Included on the iris is a lower housing having an upper mounting flange having a ball opening and a body depending from the flange, the body defining a passage through which a test ball passes. A control ring is disposed on the upper mounting surface for sliding, rotating action relative to the lower housing. A plurality of iris petals is provided, each operationally connected to the control ring and to the upper mounting flange to pivot between a closed position in which the ball opening is blocked, and an open position in which the petals are simultaneously retracted and the opening is clear for passage of a test ball.