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:
Nov. 17, 1992
Filed:
Aug. 14, 1991
Hiroshi Kawakami, Youkaichi, JP;
Shuji Asada, Youkaichi, JP;
Sadahiro Shimada, Youkaichi, JP;
Mitsuo Ishii, Shiga, JP;
Matsushita Electric Industrial Co. Ltd., Kadoma, JP;
Abstract
A dust detector in a vacuum cleaner includes a light-emitting element exposed into a dust suction passage for emitting a light beam into the dust passage, and a light-detecting element exposed into the dust suction passage for detecting the light beam emitted from the light-emitting element. A detector unit detects the amount of dust flowing through the dust suction passage based on the intensity of the light beam transmitted from the light-emitting element across the dust suction passage to the light-detecting element. The light-emitting element and the light-detecting element are covered respectively by a pair of light-transmissive covers having respective end faces exposed into the dust suction passage and lying flush with an inner wall surface of the dust suction passage.