Battery charging apparatus

• US 20040164710A1
• Filed: 02/21/2003
• Published: 08/26/2004
• Est. Priority Date: 02/21/2003
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: McNeill, James Thomas
• Granted Patent: US 6,859,012 B2
• Time in Patent Office: Days
• US Class Current: 320/133
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence

Abstract

A load, such as a cordless telephone handset, is powered by a rechargeable battery. The battery is recharged, when the load is not in use, by a battery charger which is controlled by a usage timer which totals the amount of time that the load has drawn power from the battery since the last recharging cycle. The usage timer causes operation of the battery charger to be inhibited until after a predetermined cumulative use.

Claims

1. A battery charging apparatus comprising:

a) a rechargeable battery;

b) an intermittent load energized by said battery;

c) a timer coupled to said load, said timer generating a signal representative of elapsed time of loading of said battery by said load;

d) means for charging said battery; and

e) means for controlling said battery charging means in response to the signal generated by said timer.

2. The invention of claim 1 in which said load is a cordless telephone handset, and said timer is located in said handset.

3. The invention of claim 1 in which said load is a cordless telephone handset, and in which said means for charging said battery is located in a base unit associated with said handset.

4. The invention of claim 3, in which said timer generates a signal representative of elapsed time when said handset is remote from said base unit.

5. The invention of claim 1, in which said timer generates a signal representative of elapsed time when said load draws current from said battery.

6. The invention of claim 1, in which said load is a cordless telephone handset, and in which said means for controlling said battery charging means is located in a base unit associated with said handset.