Patent ID: 6561948
Filing Date: 2003-05-13
Classification: B60W,B60Y,F02D,F16D,F16H,Y10T

Abstract:
A method for controlling a vehicular automated transmission system (10) comprising an internal combustion engine (18) having an engine output member (136), an engine controller (38) having at least one mode of operation for controlling engine fueling to control at least one of engine speed (ES) and engine torque (ET), a multiple speed change gear transmission (14) having an input shaft (28), a centrifugal friction clutch (20) for drivingly connecting said engine output member to said input shaft, a manually operated throttle (37) for manually requesting a degree of engine fueling, a system controller for receiving input signals (54) including two or more of signals of (i) engine speed (ES), (ii) throttle position (THL), (iii) engaged transmission ratio (GR), (iv) input shaft speed (IS), (v) vehicle speed (OS) and (vi) engine torque (ET), and processing said signals according to logic rules to issue command output signals (56) to system actuators including at least said engine controller, said method characterized by the steps of:(a) providing said centrifugal clutch with a driving member (60) rotatable with said engine output member and with a driven member (62) rotatable with said output shaft; (b) configuring said centrifugal clutch to have its engagement dependent upon the rotational speed of said driving member, said clutch being disengaged at engine idle speed, said clutch becoming incipiently engaged at an incipient engagement engine speed (ESIE) greater than said engine idle speed (ESIEIDLE), said clutch achieving a maximum engagement (74/64) at at least a lockup engine speed (ESLOCKUP), said lockup engine speed greater than said incipient engagement engine speed (ESLOCKUPIE); (c) sensing vehicle launch conditions; (d) during vehicle launch conditions continuously: (i) sensing throttle position, (ii) determining a target engine speed (EST) as a function of sensed throttle position with said target engine speed being less than said lockup engine speed (ESTLOCKUP), and (iii) commanding engine speed to equal said target engine speed.