Patent Number: 6,167,588

Title: Vacuum cleaner with filter clogging indicating means

Abstract: The invention provides a vacuum cleaner having an airflow path, dust separating apparatus (16) arranged in the airflow path and a motor (24) arranged in the airflow path downstream of the dust separating apparatus (16), a pre-motor filter (20) located immediately upstream of the motor (24) and downstream and separate from the dust separating apparatus (16), and a bleed valve (18) located upstream of the pre-motor filter (20) to allow air to be bled into the airflow path in the event of a blockage occurring upstream of the bleed valve (18), wherein signalling means (30, 32, 34) responsive to a change in an operating condition of the motor (24) are provided to indicate that a blockage has occurred at or downstream of the pre-motor filter (20).

Inventors: Dyson; James (Wiltshire, GB)

Assignee: Notetry Limited

International Classification: A47L 9/10 (20060101); A47L 9/19 (20060101); A47L 9/28 (20060101); A47L 009/28 ()

Expiration Date: 01/02/2018