| 摘要 |
PURPOSE:To eliminate a speed sensor by reducing the frequency of a supply power source to decelerate a truck and maintain a creeping speed. CONSTITUTION:In order to accelerate to travel a stopped truck at high speed, the frequency of a supply power source is, for example, set to a commercial frequency. Thus, the truck is accelerated along a curve L1, and the truck arrives at the high speed of a point B soon. When the truck arrives at a deceleration starting point, this is detected by a position sensor, and the frequency of the supply power source decreases, for example, to 5Hz. Thus, the truck is decelerated along a curve L2. It is crepted with the speed at the point D that a thrust balances with the traveling resistance, and when the truck arrives at the stopping position, it is detected by the sensor to be stopped. |
