| 摘要 |
PROBLEM TO BE SOLVED: To prevent confusion of a driver by preventing over run when an engine is rotated at high speed, and checking an erroneous operation of a manual range switching valve. SOLUTION: The above speed change operating device comprises a shift lever 14, a manual range switching valve 16 disposed in a down range pneumatic piping 35 for connecting a down range cylinder 20 of a range shift unit 15 to a pneumatic source, a valve lock unit 17 enabling the switching valve 16 to be locked, and a solenoid valve 18 which is adapted to exhaust compressed air from the down range cylinder 29 and simultaneously supply compressed air to the valve lock unit 17 in the condition where when the manual range switching valve 16 is operated to the down range, the engine is rotated over the rated rotating speed according to the car speed, and the gear ratio, and exhaust compressed air from the valve lock unit 17 and simultaneously supply compressed air to the down range cylinder 20 in the condition where the engine is rotated below the rated rotating speed according to the car speed and the gear ratio. |
