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Calculator driving and battery pack recharging circuit

  • US 4,140,957 A
  • Filed: 06/20/1977
  • Issued: 02/20/1979
  • Est. Priority Date: 06/20/1977
  • Status: Expired due to Term
First Claim
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1. A circuit adapted to be driven by a source of battery power or by a supply of d.c. power, said circuit comprising:

  • contact means having first and second ends to selectively connect one of a rechargeable battery source or a disposable, non-rechargeable battery source into said circuit for driving said circuit from said source of battery power,the first end of said contact means connected to the circuit to be driven, and the second end of said contact means having a first and a second contact, the second end of said contact means selectively connected to one of the rechargeable battery source by said first contact or to the disposable, non-rechargeable battery source by said second contact when said circuit is driven from said source of battery power, andterminal means adapted to apply a d.c. voltage to said circuit for alternatively driving said circuit from said supply of d.c. power,said terminal means moved into engagement with the first end of said contact means in order to apply the d.c. voltage to said rechargeable battery souce to thereby recharge said rechargeable battery source, and the second contact of the second end of said contact means accordingly being moved out of connection with said contact means in response to the movement of said terminal means to thereby electrically isolate said non-rechargeable battery source from said circuit and from said supply of d.c. power when said circuit is alternatively driven from said supply of d.c. power.

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