TWO STEP SMART KEY START SYSTEM

Abstract

A keyless ignition start system in which authentication of a coded key fob is carried out twice, first to activate the ignition switch to allow starting the engine and second at the time when the brake pedal is depressed to put the car in a drive gear. The two step authentication prevents driving off a car which has been started without having the key fob for security purposes and also to avoid inconvenient situations that can otherwise occur.

Claims

1. A smart key system for an automobile having an engine, transmission, and brake pedal including a coded key fob able to be detected and authenticated within a passenger compartment and authenticated by a smart key system controller and enabling an ignition switch to start said engine, said automobile also including a transmission operating lever, and a lever lock preventing shifting until said brake pedal is depressed, the improvement wherein said smart key controller again detects and authenticates the presence of the coded key fob in said passenger compartment at the time said brake pedal is depressed prior to activate said transmission lever lock actuator and release said lock and allow shifting into gear.

Description

DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 is a pictorial diagrammatic view of a portion of the passenger compartment of an automobile with keyless system components included according to the present invention being depicted diagrammatically.

[0018] FIG. 2 is a block diagram of components of the keyless system depicting the two step detection authentication operation of the invention.

DETAILED DESCRIPTION

[0019] In the following detailed description, certain specific terminology will be employed for the sake of clarity and a particular embodiment described in accordance with the requirements of 35 USC 112, but it is to be understood that the same is not intended to be limiting and should not be so construed inasmuch as the invention is capable of taking many forms and variations within the scope of the appended claims.

[0020] Referring to FIG. 1, a portion of the interior of an automobile passenger compartment 10 is shown in fragmentary form.

[0021] A center console mounted transmission shift lever 12 is provided in conventional fashion. A dash mounted starter button 14 is provided (or a turnable ignition switch which could also accept a key). A keyless system controller 16 is depicted diagrammatically which detects the presence of a coded key fob 18 in the passenger compartment 10 as by one or more car body mounted antennas 20 receiving transponder coded pulse codes transmitted by the key-fob 18 when interrogated by the smart key controller 16 in the well known manner.

[0022] The system controller 16 enables the ignition push button 14 when the presence of the correctly coded key fob 18 in the compartment 10 is detected and authenticated, such that the car can be started by merely pushing the button 14 without the use of a key, in the well known manner.

[0023] According to the present invention, a transmission lever lock 22 is provided, such as described in U.S. 2009/0151412A1, which positively prevents movement of the transmission selector or shift lever 12 to a drive position unless the brake pedal 24 is depressed and also unless the key fob 18 in the passenger compartment 12 is again detected and authenticated by the system controller 16.

[0024] According to the invention, such detection-authentication necessary to shift the lever 12 is not carried out at the same time as when the ignition detection-authentication is carried out. This second authentication is carried out at the time the brake pedal is pressed and a signal is generated and sent by a sensor 26 which detects the pressing of the brake pedal 24 to the smart key controller 22, which carries out a second detection authentication of the key fob 18 prior to operating the release of the transmission lever lock actuator 22.

[0025] Thus, if the key fob 18 is removed from the passenger compartment 10 after the car is started, the vehicle will not be able to be operated as the transmission lever 12 will remain locked even when the brake pedal is pressed.

[0026] This prevents operation of the vehicle even after the key fob 18 has been initially authenticated and the car started and running, and thus positively prevents operation of the vehicle unless the key fob 18 is authenticated as being within the passenger compartment.