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:
Feb. 02, 1982
Filed:
Aug. 30, 1979
Applicant:
Inventors:
Assignee:
Konishiroku Photo Industry Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08B / ;
U.S. Cl.
CPC ...
340617 ; 7329 / ; 310321 ; 310323 ; 310338 ; 340621 ;
Abstract
An apparatus for detecting a residual quantity of toner remaining in the supply hopper of a copying machine includes a piezoelectric vibrating element disposed in a wall of the hopper and having a surface normally positioned in contact with toner in the hopper, and an electronic circuit for causing vibration of the element at a predetermined frequency and for detecting changes in operating characteristics of the element as representative of a decrease in the amount of toner in the hopper to operate a warning device.