Patent ID: 8010255
Filing Date: 2011-08-30
Classification: B60N,B60R,G01D

Abstract:
1. A sensor circuit for a removable seat for a motor vehicle, comprising the seat incorporates a first inductor to form part of an inductive coupling between the first inductor and a second inductor that is mounted to a floor of the motor vehicle forming a contactless-transmission arrangement extending between the seat and the floor of the motor vehicle, the first inductor forming part of a resonant circuit mounted to the seat which incorporates at least one capacitor and has a resonant frequency, the resonant frequency of the resonant circuit being variable in response to a sensed parameter, and a signal processing circuit for detecting between resonance conditions of the resonant circuit based on response to the sensed parameter, wherein the resonant circuit includes a switch associated with the at least one capacitor to switch the capacitor in and out of the resonant circuit in response to the sensed parameter, such that the resonant frequency of the resonant circuit depends upon the sensed parameter, the switch together with the capacitor incorporated in the part of the resonant circuit that is mounted to the seat and which is associated with the first inductor, wherein the signal processing circuit includes a signal generator and an analyser, wherein the signal generator is connected to a first side of the second inductor through a load, the second side of the second inductor being connected to the analyzer, the signal generator generating a first signal having a first frequency, a second signal being provided to the analyser from the second inductor, the second signal having a second frequency based on the first frequency and the resonant frequency of the resonant circuit, the analyser determining the resonant frequency based on the second frequency and identifying a sensed parameter based on the resonant frequency.