Patent ID: 6522965
Filing Date: 2003-02-18
Classification: B60W,F16H,Y10T

Abstract:
A method carried out by an electronic transmission control for setting a multiplication of a continuously variable automatic transmission having a variator (CVT transmission) for a motor vehicle having the electronic transmission control, said control having a control unit with a microcomputer connected with one of sensors and external control units to detect several operating parameters and with an actuator wherein a starting clutch is actuatable by the actuator, said method comprising the following steps:a) determining in a test module (M1 or M1â€²), by comparison of a set of input signals in the control unit with a predefined characteristic data, if a predefined operating situation exists in which a program module (M2 or M2â€²) is activated for adaptation of an existing transmission multiplication (i_v_ist) to one of a vehicle speed (v_F) and an output rotational speed (n_ab) of the transmission; and determining in the negative, in a processing function (F6, F9 or F15 respectively), a transmission specified multiplication (i_v_strategy, i_v_start) from a characteristic field as a new transmission specified multiplication (i_v_soll) for a regular driving strategy; b) in the program module (M2 or M2â€²) for adaptation of the transmission specified multiplication (i_v_soll), testing in a differentiation function (F2 or F16) if one of the vehicle speed (v_F) and the output rotational speed (n_ab) of the transmission is higher than a predetermined limitation value (v_F_limit, n_ab_limit); and c) for a positive inquiry of the differentiation function (F2 or F16), and when the starting clutch is closed, assigning a predefined transmission specified multiplication (i_v_ABS), i_start_w) to a detected operation state and setting the predefined transmission specified multiplication (i_v_ABS), i_start_w) as the new transmission specified multiplication (i_v_soll); in case of negative inquiry a processing function (F4 or F17), starting to at least partly open the starting clutch and assigning to the operating state the predefined transmission specified multiplication (i_v_ABS, i_start_w) and setting the transmission specified multiplication (i_v_ABS, i_start_w) as the new transmission specified multiplication (i_v_soll).