US 2006/0124375 A1 · Vehicle lift interlock

Abstract

An interlock for a vehicle platform lift meets the Federal Motor Vehicle Safety Standards (FMVSS 403) effective in late 2004 with minimum modification of vehicle electronic control arrangements. The interlock prevents forward and rearward mobility of vehicles unless the platform lift is stowed. The interlock operates to prevent accidental release but does not affect vehicle movement when the platform lift is stowed. Operation of the lift is allowed by placing the transmission in park or by placing the transmission in neutral and actuating the parking brake. A vehicle body computer controls operation when the vehicle is running. A bypass enable relay allows use when the vehicle's engine is not running.

Claims14

Dependent claims

A platform lift interlock for a motor vehicle comprising:

a vehicle data network;
a brake system controller and a parking brake, the brake system controller being coupled to the parking brake for reporting the state of a parking brake over the vehicle data network;
a transmission controller and a transmission, the transmission controller being coupled to the transmission for obtaining the state thereof and for reporting the state of the transmission over the vehicle data network;
a body computer coupled to the vehicle data network for receiving the signals relating to the states of the transmission and the parking brake, the body computer being further programmed to generate a platform lift enable signal in one of two states responsive to the signals relating to the states of the transmission and the parking brake;
and
a first enable relay coupled for energization to the body computer for receiving the enable signal.

3 more elements

A vehicle comprising:

a wheelchair door;
a wheelchair door switch having a state controlled by the position of the wheelchair door;
a body computer coupled to sense the state of the wheelchair door switch;
a data network connected to the body computer;
a plurality of controllers coupled to the data network for reporting states including the state of a parking brake and the state of a transmission over the data network;
the body computer being programmed to respond to an open state of the wheelchair door, the parking brake being set and the transmission being park or neutral for generating an enable signal;
a first enable relay connected to the body computer for receiving the enable signal;
an ignition switch;
a second enable relay connected to the ignition switch for energization in response to placement of the ignition switch in a keyoff position;
a platform lift mechanism;
and
a power relay having a high side input connected to the outputs from the first and second enable relays, a low side input connectable to ground through the wheelchair door switch and a power output connected to the platform lift mechanism.

9 more elements

An energization control system for a vehicle platform lift comprising:

a power source;
a power relay having high and low side inputs for connecting the power source to the vehicle platform lift;
an ignition switch;
an ignition enable relay connected to apply an energization signal to the high side input of the power relay, the ignition enable relay having an energization input connected to the ignition switch for connecting power through the ignition enable relay when the ignition switch is in a keyoff position;
parking brake and transmission state signal sources;
a state enable relay connected to apply an energization signal to the high side input of the power relay responsive to an enable relay drive signal;
and
an enable relay drive signal generator responsive to selected parking brake and transmission state signals for generating an enable signal for application to the state relay.

5 more elements

Dependencies are inferred from the claim text.

Vehicle lift interlock

Life of this patent

Vehicle lift interlock

Life of this patent

Abstract

Claims14