| 摘要 |
1505778 Vacuum cleaners ELECTROLUX Ltd 22 July 1976 [20 Aug 1975] 30625/76 Heading A4F [Also in Division B1] A vacuum cleaner bag 16 Fig. 2 (not shown) has an end-plate 19 with a central dust inlet 20. and at least one further aperture 21 which is bridged by the inwardly folded pervious wall to form a filter 25. In use a clogging indicator comprising a piston 12 slidable in a transparent plastics cylinder 11 is subject to the pressure drop across the bag via passages 15 and 17, passage 15 communicating with the bag interior through aperture 21 and filter 25 so that dust is excluded from the cylinder, while passage 17 opens into the vacuum cleaner housing outside the bag 16. Passage 15 includes a rubber funnel which presses against plate 19. The plate, inlet 20 and aperture 21 are made by punching, glue is applied to the plate and the pervious wall secured thereto. Two apertures 21 may be provided on opposite sides of inlet 20 to allow the bag to be located in either of two positions. |
