Keyless entry system
Patent 5204672 Issued on April 20, 1993. Estimated Expiration Date: 
January 14, 2011. 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.
January 14, 2011. 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 ReferencesSwitch and lock activating system and method Automobile burglar alarm and arming circuit for same Automotive keyless entry system incorporating portable radio self-identifying code signal transmitter Alarm, security, and protection system for a motor vehicle Vehicle-use locking and unlocking system Radio-wave transmission system of keyless entry system for automotive vehicle devices Patent #: 4897644 InventorApplicationNo. 641162 filed on 01/14/1991US Classes:340/825.71, Frequency responsive actuation340/5.31, Lockout or disable340/5.65, Electronic coded record340/5.72Vehicle doorExaminersPrimary: Yusko, Donald J.Assistant: Magistre, Dervis Attorney, Agent or FirmForeign Patent References
International ClassH04B 005/00AbstractA keyless entry system is provided for locked or disabled items. A transmitter carried by a person generates a signal with a predetermined frequency characteristic such that the generated signal is transmitted through the carrier's body. There is a receiver apparatus including a detector for detecting a signal with the predetermined frequency characteristic and a mechanism that is engageable by the carrier's body for providing signals transmitted through the body to the detector. When such signals are detected, a circuit is activated to unlock or enable the item. An alarm system may be provided which sounds under certain predetermined conditions and a latching mechanism may be utilized to disarm the alarm under certain conditions. | |
