3840795 is referenced by 110 patents and cites 9 patents.

A battery operated appliance comprising a power unit having a rechargeable battery therein and a charging unit having a recess for insertion of the power unit therein for recharging the battery within the power unit, a transformer including one winding in the power unit and one winding in the charging unit. In one embodiment the magnetic core structure associated with one of the windings is at least in part defined by the casing of the rechargable battery. Various core structures may be employed to ensure good inductive coupling between the respective windings.

Title
Hand held battery operated device and charging means therefor
Application Number
05/004,712
Publication Number
3840795
Application Date
January 21, 1970
Publication Date
October 8, 1974
Inventor
Barnas Jr Louis A
Roszyk Leon M
Agent
Clark Esquire George R
Assignee
Sunbeam Corporation
IPC
H02j 07/00
H02J 07/02
A61C 17/16
A61C 17/22
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