| 摘要 |
<p>The lid includes a pressure relief device by which gases or pressure can be vented, but which will not permit escape of liquid even if liquid level above that of the opening. The lid comprises a screw on cap with a central depression, and a hole in the middle. The pressure relief device is in the form of a disc, also with a central depression, placed above the lid. The disc has a central plug which is pushed through the hole, holding the assembly together elastically. The lid has vent holes through which gas can pass to a space between the two components. This space is sealed by a lip on the upper disc. If excessive pressure occurs, the disc deforms elastically lifting the lip and venting to atmosphere.</p> |
