×

Battery charger

  • US 5,949,220 A
  • Filed: 05/26/1998
  • Issued: 09/07/1999
  • Est. Priority Date: 09/27/1996
  • Status: Expired due to Fees
First Claim
Patent Images

1. A battery charger that outputs a predetermined voltage even when a power supply device having a rechargeable battery is not connected to said battery charger so that said battery charger can supply said predetermined voltage to said power supply device whenever said power supply device is connected to an output terminal of said battery charger, comprising:

  • periodic signal producing means for supplying a periodically varying periodic signal to said output terminal; and

    detecting means for checking whether said power supply device is connected to said battery charger or not by checking through a filter whether said periodic signal is present at said output terminal or not.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×