| 摘要 |
PURPOSE:To improve the safety of a vehicle by providing a control means changing the transmission gear ratio of an automatic transmission to a low speed side when a device is brake-operated in a condition where abnormality occurred in a brake device based on the detected information of an abnormality detection means and an operation condition detection means. CONSTITUTION:Brake liquid quantity in a reservoir tank is detected by a brake liquid quantity sensor 3 (abnormality detection means), and when the liquid quantity reduces to unsufficing quantity to brake, an abnormality signal Bx is outputted to a transmission control device 4 (control means). The push-down quantity (brake operation condition) of a brake pedal is detected with a brake sensor 5, and a brake operation signal Brk corresponding to the push-down quantity is outputted to the transmission control device 4. The number of revolution of an engine is detected with an engine number of revolution sensor 6, and a number of revolution signal Ne corresponding to the said number of revolution is outputted to the transmission control device 4. In the control device 4, a control program stored in an inner memory is carried out based on output signals from sensors 3, 5, and 6, the signals are outputted to an automatic transmission 1, and an engine brake is applied at the time of the abnormality of a brake device. |
