| 摘要 |
<p>1521198 Automatic control of speed TOYOTA JIDOSHA KOGYO KK 21 July 1976 [2 April 1976] 30311/76 Heading G3R In a vehicle speed control system, a vehicle speed dependent voltage is compared with upper and lower limits, to generate an "off" signal if greater than the upper limit and an "on" signal is less than the lower limit. In response to an "on" signal, a throttle valve is opened and, using an electromagnetic relay, a connection made between a vehicle battery and ignition coil, this connection not being made for an "off" signal. As shown, the speed dependent voltage from tachometer 40 is fed to comparator 90 to be compared with an upper limit set by resistors Ro, R 1 , R2 or a lower limit set by R 0 and R 1 . In the latter case, R 2 is shorted by transistor Tr 2 whenever the actual speed exceeds the upper limit, using the inverted comparator output. The output of the comparator forms the "on" or "off" signals which control a switching transistor Tr 1 in series with the electromagnetic relay 42. The throttle valve is opened in, response to the energization of relay 42, provided the vehicle accelerator is pressed and provided the engine is not in neutral or low gear, or the clutch not connected. Thus the acceleration or deceleration of the engine is controlled so as to keep its speed between the upper and lower limits. In an alternative, Fig. 1 (not shown), the upper and lower limits are independently set and each compared with the actual motor speed signals, to control a flip-flop circuit connected to the transistor Tr 1 . Details of the engine starting circuit and ignition circuit are also given on that figure.</p> |
