Hands-free device for use with a cellular telephone in a car to permit hands-free operation of the cellular telephone
November 12, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesMulti-level power amplifying circuitry for portable radio transceivers Wireless mobile telephone communication system Control circuit for mobile telephone with full duplex operation capability Vehicular hands-free telephone system Power booster for a radio telephone Power control with a constant gain amplifier for portable radio transceivers Cellular hand held portable speakerphone system having an interface adapter Portable radio telephone used with an adaptor unit having a hand-free circuit Adapter unit for adaptively supplying a portable radio telephone with power Portable radio device with on-vehicle adaptor system InventorApplicationNo. 745493 filed on 11/12/1996US Classes:379/388.02, Speakerphone with build-in microphone379/390.01, Amplification or attenuation level control379/420.02, Hands-free loudspeaker feature379/420.03, Hands-free microphone feature455/569.2In vehicleExaminersPrimary: Zele, Krista M.Assistant: Weaver, Scott L. Attorney, Agent or FirmInternational ClassH04M 009/00AbstractA hands-free device is adapted for use with a cellular telephone in a car to permit hands-free operation of the cellular telephone, and includes a main terminal, a secondary terminal, and a microphone provided on one of the main and secondary terminals. The main terminal includes a first casing, a power supplying unit, a voltage regulating circuit, a first connector, an audio output amplifier circuit, and a sound output unit. The secondary terminal includes a second casing, a second connector connected removably to the first connector, a third connector connected removably to the cellular telephone, a hands-free control circuit, a voltage output control circuit, and a gain control circuit. The secondary terminal can be replaced so that the hands-free device can be used with any type of cellular telephone without changing the main terminal.Field of SearchAmplifying (e.g., AGC or AVC)Power supply (e.g., battery feed) TERMINAL Having distinct circuitry support structure (e.g., circuit board) Loudspeaking set Specified terminal configuration (e.g., novelty type) Casing or enclosure, per se TERMINAL ACCESSORY OR AUXILIARY EQUIPMENT With circuit connection to terminal Including coupler (e.g., inductive) With feedback of modulated output signal With casing or housing Power booster Power supply Battery charging | |
