A collecting bag is provided with a vent aperture to allow for escape of gases which may accumulate in the bag during use. The vent aperture is formed in an extension member that is connected with the bag member. In order to bring the vent aperture from a fully open condition to a fully closed condition,...http://www.google.fr/patents/US7150728?utm_source=gb-gplus-shareBrevet US7150728 - Collecting bag having a vent aperture
