| 摘要 |
<p>PURPOSE:To prevent a notch of a device for protecting an electric motor vehicle from overrunning by detecting the line voltage drop to thereby turn a cam shaft advance instruction off. CONSTITUTION:If a line breaker 3 is closed to drive a main motor 5 when an electric motor vehicle is started and accelerated, a drive signal is applied from a brake logic unit 14 to a pilot motor 13 upon increase of revolution to revolve a cam shaft to sequentially operate cams 10 to 12 to thereby sequentially close contactors 7 to 9 for advanching the notch. Since an advance signal is automatically advanced under the condition that the current flowing through the motor 5 becomes lower than predetermined value, the logic unit 14 continues to produce the advance signal even if a pantograph is separated in short time, but since an interlocking contact 17 of a no voltage relay 15 is inserted into a cam shaft advance instructing circuit, the contact 17 is released, when the pantograph is separated, to turn the cam shaft advance instruction off.</p> |
