| 摘要 |
<p>A straining device for a drainage pump, the straining device comprising a body defining an inner chamber; at least one straining element by which liquid may enter the chamber; and at least one outlet by which liquid may leave the chamber. The straining device further includes a liquid level sensor arranged to detect the level of a liquid in which said straining device is located during use and, upon determining that said liquid level exceeds a threshold, to cause an activation signal to be sent to said pump. The liquid level sensor comprises non-contact sensing means such as an electric field sensor. The sensor is located at the top of the straining device and arranged to project its sensing field upwardly.</p> |
