The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 23, 1991
Filed:
Nov. 15, 1989
Manfred Kraft, Neubulach, DE;
Gerhard Kurz, Stuttgart, DE;
Interlava AG, Lugano, CH;
Abstract
A device for controlling the operation of a vacuum cleaner and for signalling the dust bag fill level, the existence a clogged pipe or of secondary air openings, or the like has an air turbine arranged in the exhaust air flow generated by the blower of a vacuum cleaner, downstream of the dust bag, whose rotary speed or the air turbine is detected in a non-contact manner, converted into an electric indication signal and supplied to a control circuit which controls the blower motor. Based upon the rotary speed so detected, it is then possible to determine the momentary operating conditions of the vacuum cleaner and/or the dust bag fill level, to emit signals warning the operator that the dust bag has to be changed, and also to display finely graded percentage statements or applicable text messages for the user. By combining this information with pressure values picked up by diaphragm-type switches, it is possible to accurately determine the operating conditions to be indicated.