Movable or removable seat for a motor vehicle

• US 8,010,255 B2
• Filed: 05/07/2004
• Issued: 08/30/2011
• Est. Priority Date: 05/09/2003
• Status: Active Grant

• Current Assignee: Autoliv AB (Autoliv Incorporated)
• Original Assignee: Autoliv AB (Autoliv Incorporated)
• Inventors: Darraba, Roger
• Primary Examiner(s): Hellner; Mark
• Assistant Examiner(s): Mawari; Redhwan
• Application Number:
  US10/556,549
• Publication Number:
  US 20070102999A1
• Time in Patent Office: 2,671 Days
• Field of Search: 701/45, 701/1, 701/4, 701/13, 701/29, 701/120, 701/300, 701/301, 342/29, 342/30, 342/33, 342/455, 342/357.08
• US Class Current: 701/45
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: B60N 2/0224 Non-manual adjustments, e.g. with electrical operation
• CPC Class Codes: B60N 2/0264 characterised by the type of electrical connection, e.g. wiring, plugs or USB
• CPC Class Codes: B60R 2021/01088 wireless
• CPC Class Codes: B60R 2021/01265 Seat belts
• CPC Class Codes: B60R 21/01546 using belt buckle sensors
• CPC Class Codes: B60R 21/01548 sensing the amount of belt winded on retractor
• CPC Class Codes: G01D 5/204 by influencing the mutual induction between two or more coils G01D5/22 takes precedence
• CPC Class Codes: G01D 5/48 using wave or particle radiation means G01D5/26 takes precedence

Abstract

A movable or removable seat for a motor vehicle is disclosed which preferably takes the form of a re-movable vehicle seat (1). The removable seat incorporates a first inductor (17) which forms part of an inductive coupling between the removable seat and a second inductor (21) which is mounted on the motor vehicle. The first inductor forms part of a resonant circuit which incorporates at least one capacitor. The resonant frequency of the resonant circuit is variable in response to a sensed parameter such as, for example, the position of a head-rest of the seat, the inclination of the back-rest of the seat and such like. A central unit (23) generates a square wave which excites the resonant circuit. A signal is transmitted from the resonant circuit to the central unit (23) which analyses the resonant frequency of the resonant circuit.

Claims

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.

2. A sensor circuit according to claim 1 wherein the sensed parameter is the position of a height adjustable belt deflector.

3. A sensor circuit according to claim 1 wherein the sensor parameter is the position of a head-rest of the seat.

4. A sensor circuit according to claim 1 wherein the sensed parameter is the inclination of a back-rest of the seat.

5. A sensor circuit according to claim 1 wherein the sensed parameter is the condition of part of a seat-belt system.

6. A sensor circuit according to claim 5 wherein the sensed parameter is a condition of a seat-belt retractor.

7. A sensor circuit according to claim 5 wherein the sensed parameter is the condition of a safety-belt buckle.

8. A sensor circuit according to claim 1 wherein the sensed parameter is weight applied to a seat cushion of the seat.

9. A seat according to claim 1 wherein the resonant circuit incorporating a plurality of capacitors each with a respective switch to enable the capacitors to be switched individually in and out of the resonant circuit and wherein the respective switches responsive to one of a plurality of sensed parameters.

10. A sensor circuit according to claim 1 wherein the resonant circuit is a passive circuit which does not include an electrical power supply carried by the seat.

11. A sensor circuit according to claim 1 wherein the resonant circuit has two resonant frequencies depending upon the condition of the switch, and the signal generator and signal analyser is configured to generate the exciting signal such that the resonant circuit has resonant frequencies which are odd harmonics of the base frequency of the exciting signal.

12. A sensor circuit according to claim 1 wherein the signal generator and signal analyser is adapted to generate a plurality of exciting signals, each exciting signal having a different frequency which is one of a plurality of resonant frequencies of the resonant circuit.

13. A sensor circuit according to claim 1 wherein the signal generator and signal analyser is configured to generate successive exciting signals having different resonant frequencies.

14. A sensor circuit according to claim 1 wherein the signal generator and signal analyser is configured to generate the exciting signal during one period of time and analyse at least one of the transmitted signals during a succeeding period of time.

15. A sensor circuit according to claim 1 wherein the signal generator and signal analyser is configured to generate the exciting signal and analyse at least one of the transmitted signals simultaneously.

16. A sensor circuit according to claim 14 wherein the signal processing circuit is configured to take an average of the transmitted signals, and compare the phase of the average with the phase of the exciting signal.