| 摘要 |
For cleaning an article formed of non-rigid fabric such as a tubular filter (5) low frequency air pulses are directed at the article in the form of a concentrated beam to cause the material to vibrate while the article is rotated to expose different portions to direct impingement. The frequency is varied in the range 10 to 100 Hz while observing the article through window 24, and the frequency is held constant for a period at those values where the article resonates. The frequency may return to resonant values more than once in a cleaning operation. <IMAGE> |
