| 摘要 |
PURPOSE:To minimize the high-speed rotation of an engine required for purifying exhaust gas by fixing and retaining an automatic speed change gear at a low-speed step in starting a cooled engine, and then releasing such fixed state when water temperature, the rev. count of an engine or the time elapsed after starting meets a prescribed condition. CONSTITUTION:After an engine is started, the condition of the engine is decided in a control circuit 6 by a signal from a water temperature sensor 7. When the water temperature is within a fixed range of temperature, and hence the engine is decided as a cooled condition, a relay 5 is turned on. Then, a down-shift solenoid 4 is excited to fix an automatic speed change gear at the first speed step, so that even if running is started, the gear is checked from automatically changing to high-speed side, thereby to keep the engine at high-speed rotation and promote the temperature rise of a catalyzer or the like. When the water temperature reaches a fixed high temperature, the time passes fixed hours after starting or the rev. count of the engine goes to high-speed rotation, the relay 5 is turned off to deenergize the down-shift solenoid 4, and hence the automatic speed change gear is released from the first speed step and restored to the automatic speed changeable condition. |
