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:
Jul. 18, 1989
Filed:
Nov. 16, 1987
Robert H Munnig Schmidt, Drachten, NL;
Geert J Bosscha, Drachten, NL;
U.S. Philips Corporation, Tarrytown, NY (US);
Abstract
In a device where a load (R.sub.1) is powered by a battery (6), if a detection means (10) detects a battery voltage below a first threshold value (V.sub.1) defined by an adjustable voltage source (20), a first time-measurement means (40, 50) measure the time interval during which the load 6 is powered by the battery (6), at a voltage below the first threshold value. If subsequently, the load is switched off and is not connected to the AC supply voltage via a power-supply circuit (1), the battery is discharged by a discharger (30). Second time-measurement means (40, 60) measure the time interval during which the discharger is operative until the detection means detect a battery voltage below a second threshold value (V.sub.2), which is defined by a voltage source (25) and at which the battery may be regarded as fully discharged or drained. After comparison of the sum of the time intervals measured by the first and the second time-measurement means with a reference value, correction means (70) correct the first threshold value in such a way that during a next discharge the time measured is more in agreement with the reference value.