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:
Feb. 10, 1992
Kenji Isono, Narashino, JP;
Tetsuro Goto, Funabashi, JP;
Nikon Corporation, Tokyo, JP;
Abstract
There are disclosed a secondary battery detachably mountable on a camera body, a camera body on which such secondary battery is mountable, and a battery system including such secondary battery and such camera body. A system includes a battery pack equipped with a circuit for calculating the charge/discharge amount of the battery and a device for displaying the remaining capacity of the battery obtained from the calculation, the display device being so positioned as to be observable from the rear side of the camera. In another embodiment, a primary battery pack or a secondary battery pack is selectively mounted to the camera body, and a display device on the camera body indicates the remaining capacity of either pack mounted on the camera. In still another embodiment, the calculation of charge/discharge amount is made more precisely, by controlling the timing of calculation according to the on/off timing of loads in the camera such as motors. In another embodiment, the camera body is equipped with a circuit for calculating the charge/discharge amount of battery while the battery pack is provided with a memory for storing its remaining capacity, and information is exchanged between the calculating circuit and the memory. In this manner the remaining capacity can be exactly detected and displayed even when the battery pack is changed.