| 摘要 |
<p>DONALD J. BOERSMA An improved drain cover comprising a one-piece top disc and depending cylindrical body adapted to be readily inserted into a drain pipe with the disc resting on the floor and overlying the pipe opening. The body is formed with four radial slots in which trapezoidal locking slugs are slidably positioned. The body is also formed with a central bore, the lower portion of which is adapted to receive a frusto-conical camming plug. A threaded bolt is slidably positioned through the disc and is threadedly engageable with the plug. When the bolt is tightened, it raises the plug into the bore where it cams the slugs outwardly into locking engagement with the drain pipe.</p> |
