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:
Oct. 22, 2013
Filed:
May. 02, 2011
Yoshinobu Nakajima, Kyoto, JP;
Mamoru Nomoto, Osaka, JP;
Masaya Yamamoto, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An image projection device includes a replaceable air filter placed near an opening of a housing, a switcher for switching step by step a working area of the air filter, an air-speed meter for detecting a pollution level of the air filter, and a controller for controlling the switcher. When the air-speed meter detects that the pollution level of the air filter reaches a given threshold, the controller prompts the switcher to switch the working area of the air filter, and then detects a pollution level of the air filter after the switchover for determining whether or not the working area before the switchover needs to be switched.