| 摘要 |
A speed change control method for hydraulically operated multistep transmissions, which is capable of preventing the shift hunting without reducing the acceleration, and of minimizing a shock, which occurs when the speed is changed, even when a small-capacity hydraulic clutch is used. According to this speed change control method, a speed changing operation is carried out by using a controller (30) when the speed increasing/decreasing conditions have been established. A speed decreasing operation subsequent to a speed increasing operation, and a speed increasing operation subsequent to a speed decreasing operation are carried out after the lapse of a long speed change suspension time, and a speed changing operaton in a case other than these cases is carried out after the lapse of a short speed change suspension time. Only when the speed is changed from a high-speed step to a lower speed step through a coasting operation, a speed decreasing operation is carried out with a direct-coupled clutch (8) in a torque converter (3) left in an engaged state, and, in a case other than this case, a speed change operation is carried out with the direct-coupled clutch in a released state. |
