Patent ID: 7688223

Claim:
System for assisting a driver of an industrial truck comprising: a plurality of transponders ( 20 ), having active and inactive states, and normally being in the inactive state, and being arranged at predetermined points of the working area of the industrial truck ( 10 ), the plurality of transponders receiving at a LF frequency and transmitting at a UHF frequency; the transponders ( 20 ), upon receipt of the LF frequency signal, switch from the inactive state to the active state and transmit a UHF frequency signal; the industrial truck ( 10 ) having at least one transmission and receiving device and at least one antenna for transmitting and/or receiving a signal towards and from at least one transponder, the transmission and receiving device transmitting at a LF frequency and receiving at a UHF frequency; the transponders transmit the UHF-signal upon receipt of the LF signal from the transmission and receiving device; an electronic evaluation unit ( 16 ) for the UHF-signals is arranged on the industrial truck ( 10 ) and the electronic evaluation unit is connected with an on-board-computer in the industrial truck so that an indication for the driver is generated or a speed of the industrial truck is influenced through a control means for a driving means for the industrial truck; further characterised in that the transponders ( 20 ) are fitted with batteries and upon receipt of the LF frequency signal, transmit the UHF frequency signal, the industrial truck has a first aerial for transmitting the transmission signal, and the evaluation unit has a second aerial for the receipt of the UHF frequency signal, and further characterised in that on the industrial truck a monitoring circuit is provided which monitors the functions of the industrial truck, data relative to the functions of the industrial truck are stored in the transponder which correspond to prohibited functions or mandatory functions at the location of, or in the vicinity of, the transponders and the monitoring circuit compares the signals coming from the transponders with the respective function and it is indicated to the driver on a display when the respective function deviates from the prohibited function or mandatory function contained in the signal.