| 摘要 |
<p>PURPOSE:To provide a filter with a fine filter element which prevents passage of water and takes less time than prior art products for starting at initial sucking in spite of finess thereof while suction resistance of which is low enough and exchanging and cleaning of which is easy upon being clogged. CONSTITUTION:A filter element 27 is removably fixed between a suction port 20b and a suction hole 23 both for suction cup frame 20. The filter element 27 is formed integrally with a retaining ring 28 made of rubber and the like. The suction hole 23 is provided through a rim portion 22 protruding in the suction cup frame 20 with a ventilating groove 26 or holes communicating between in-and-out side of the protuberance, and the waterproof filter element 27 is held in contact with the rim portion 22. Thus, deflection of the filter element 27 is prevented and the ventilating groove 26 becomes to be an air passage between the suction hole 22 and a space of a suction chamber 20a enclosed with the filter element 27 upon sucking operation. Owing to such air passage construction, the whole area of the filter element 27, having the same diameter with the suction port 20b, may be utilized for sucking operation through above-described space.</p> |
