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:
Apr. 08, 1986
Filed:
Oct. 01, 1984
Gerhard Kurz, 7262 Althengstett, DE;
Other;
Abstract
Protective device for dust collecting devices, in particular vacuum cleaners such as wheel-mounted or hand vacuum cleaners, whereby the presence of any dust behind the dust collecting vessel, due to a damage to the dust collecting vessel, is detected by means of an electric sensor comprising a light receiver and a light transmitter, and supplied in the form of an electric signal to an associated evaluation circuit. The design of the evaluation circuit is such that when a given threshold value is exceeded it will respond and activate an associated blocking and braking arrangement for interrupting the operation of the vacuum cleaner abruptly. This prevents the collected dust, the quantities of which may be quite considerable, to be blown back within a few seconds into the environment by the continued operation of the dust collecting device in case the dust bag should for example break.