06115616 is referenced by 70 patents and cites 9 patents.

A detachable keyboard for a telephone set is provided in the form of a keyboard card clipped to the headset, which is completely detached from the body when unclipped. Wireless communication between the handset body and keyboard is used when the card is unclipped, while contacts are activated in the clipped position so that the wireless handset then functions as in the case of a non detachable keyboard.

Title
Hand held telephone set with separable keyboard
Application Number
9/86160
Publication Number
6115616
Application Date
May 28, 1998
Publication Date
September 5, 2000
Inventor
Chai Wah Wu
Ossining
NY, US
Robert Jacob von Gutfeld
New York
NY, US
Charles P Tresser
Mamaroneck
NY, US
Alejandro Gabriel Schrott
New York
NY, US
Joseph D Rutledge
Mahopac
NY, US
Arnold Halperin
Cortlandt Manor
NY, US
Agent
Whitham Curtis & Whitham
Agent
Stephen C Kaufman Esq
Assignee
International Business Machines Corporation
NY, US
IPC
H04Q 7/08
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