| 摘要 |
<p>A device for preventing backflow of a fetid gas in a drainage way comprises a device body having a drain opening which is defined at a center portion of the device body, and sidewalls which are formed on a lower surface of the flange to be fitted into the entrance of the drainage way; opening and closing means including a pair of cover plates which are rotatably installed on one pair of oppositely facing sidewalls such that distal ends of the cover plates can come into close contact with each other; and elastic members arranged at positions where the cover plates are installed on one pair of oppositely facing sidewalls, and each having one end which is held against the cover plate and the other end which is held against the sidewall, to apply elastic force to the cover plate.</p> |
