Battery voltage checking apparatus

• US 4,547,770 A
• Filed: 07/01/1983
• Issued: 10/15/1985
• Est. Priority Date: 07/08/1982
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Suzuki, Ryoichi, Tokuda, Ryuji
• Primary Examiner(s): Rowland, James L.
• Assistant Examiner(s): Myer, Daniel
• Application Number:
  US06/510,346
• Time in Patent Office: 837 Days
• Field of Search: 340/636, 354/468, 320/48
• US Class Current: 340/636.1
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: G08B 29/181 due to failing power supply

Abstract

In the disclosed battery voltage checking apparatus a first detector detects a first battery voltage level and a second detector detects a second battery voltage level. The first detector produces a signal to instruct the operator to replace the battery when the voltage level of the battery is below the first battery voltage level. Another signal is produced to inhibit camera operation when the battery voltage is below the second battery voltage level. The apparatus includes a circuit arranged to cause the first and second detectors to simultaneously detect the battery voltage level and another circuit arranged to process the signal produced from the first detector before processing the signal from the second detector.

Claims

1. A battery voltage checking apparatus for an electrical system comprising:

(a) a first detector for producing a first electrical signal indicative of a necessity for replacement of a battery used for the system when the output voltage of the battery drops to a value lower than a first voltage level;

(b) a second detector for producing a second electrical signal to inhibit operation of the system when the output voltage of the battery drops to a value lower than a second voltage level which is lower than the first voltage level;

(c) first circuit means functionally connected to the first and second detectors and for causing the first and second detectors simultaneously to detect the output voltage of the battery; and

(d) memory means for electrically memorizing, during a predetermined length of time assoicated with an exposure cycle of a camera, the first and second electrical signals produced by the first and second detectors as a result of an operation of said first circuit means; and

(e) second circuit means connected to the memory means for processihg the memorized first electrical signal before the memorized second electrical signal is processed.

2. A battery voltage checking apparatus according to claim 1, wherein said second circuit means includes:

(a) annunciating means responsive to the memorized first electrical signal for annunciating the necessity of replacing the battery; and

(b) inhibiting means for inhibiting operation of the electrical system after annunciation of the first electrical signal.

3. A battery voltage checking apparatus according to claim 2, further including:

means for operating said inhibiting means after actuating said annunciating means.

4. A battery voltage checking apparatus according to claim 1, wherein said first latching means includes a first flip-flop circuit for memorizing the first electrical signal.

5. A battery voltage checking apparatus according to claim 1, wherein said memory means includes a second flip-flop circuit for memorizing the second electrical signal.

6. A battery voltage detecting apparatus for a camera, comprising:

(a) a first detector arranged to produce a first electrical signal representative of a change of a battery used for the camera when the output voltage of the battery drops to a value lower than a first voltage level;

(b) a second detector arranged to produce a second electrical signal for inhibiting operation of the camera when the output voltage of the battery drops to a value lower than a second voltage level which is lower than the first voltage level;

(c) first circuit means, functionally connected to the first and second detectors for causing the first and second detectors to simultaneously detect the output voltage of the battery a prescribed length of time after said battery is switched on;

(d) meory means for electrically memorizing the first and second electrical signals produced by the first and second detectors as a result of an operation of said first circuit means; and

(e) second circuit means, connected to the first and second detectors, for processing the first electrical signal before the second electrical signal is processed.

7. A battery voltage detecting apparatus according to claim 6, wherein said first circuit means includes a first switch member to cause the preparation in circuit to control said camera, and said second circuit means includes a second switch member to cause the commencement of the photographic operation in said camera.