| 摘要 |
<p>The extractor removes at least part of the air from a bag (1) which can be thermally sealed after filling with a powdered product. The extractor consists of a sleeve (2) which is open at one end only and is fitted into the top of the bag to allow the air to be expelled. The sleeve is made from a permeable, e.g. filter, material which allows air to pass through it. Otherwise it can be made from an impermeable material and be equipped with a non-return valve which lets the air out but not in.</p> |
