| 摘要 |
The truck comprises a lifting mast along which moves a fork unit with a support frame and forks. The forks are movable from a central position on the frame to one extending from the side of the truck. A position monitor optical indicator reads out continuously the fork movements, and a micro-processor to which it is connected calculates the position of the forks, providing control signals to the fork drive for pre-programmed movement purposes. In calculating the fork position, the micro-processor receives two phase-displaced pulse trains from the pulse transmitter incorporated in the optical indicator. A separate signal transmitter provides a signal to the micro-processor when the forks are located in their central position, the processor setting back to zero the pulse calculation and interrupting the fork movement. A circuit changeover switch allows differing pre-programmed movements to be connected to the micro-processor, such as different stop positions, speed reduction or acceleration. The micro-processor or transmits data to teh truck driver as to the position of the forks. |
