Abstract: A system and method for completing an automatic up-shift during an engine progressive governor event in a controller-assisted, manually shifted compound transmission system (10) and splitter shift control therefor. Auxiliary splitter section (16B) shifts are automatically implemented by a splitter shifter (28) under commands (56) from a controller (48). The controller (48) overrides the engine governor control and controls engine torque to approach, and preferably reach a zero torque condition and bring the transmission to a splitter-neutral condition to enable an automatic up-shift when the splitter button has been selected or lever shift has been moved by the operator. Depending on the type of shift event, the transmission will automatically complete the upshift or the operator can manually complete the upshift after engine synchronization.

Abstract: An improved system and method for detecting solenoid-related faults in a solenoid-controlled actuator assembly. The system includes a processing circuit which controls a solenoid driver circuit for energizing and de-energizing the solenoid, a current sense circuit for sensing the current in the solenoid, and a power supply switching circuit for selectively connecting and disconnecting a supply voltage from the solenoid driver circuit. The processing circuit implements fault detection logic wherein the processing circuit senses the current in the solenoid and, if the sensed current exceeds a predetermined current value for a predetermined time period, disconnects the supply voltage from the solenoid driver circuit and measures the rate of voltage decay in the solenoid driver circuit to determine if an open circuit fault or a short circuit fault exists.

Abstract: An improved control method/system for controlling engine speed (ES) of an electronically controlled engine (12) communicating over an industry standard data link. If the difference between engine speed and target engine speed exceeds a reference value ((ES−ESTARGET)>REF?), then the engine is commanded to operate in a torque control mode or a speed- and torque-limiting mode (64).

Abstract: A manually shifted, range-type compound transmission (110) is provided with enhanced automatic range shifting. A controller (222) receives input signals indicative of shift selector operation and of vehicle speed (OS) and automatically commands range shifts as a function of both system parameters.

Abstract: A control for preventing damage to a vehicular driveline (10) during attempts to launch a vehicle from a stopped condition while engaged in an inappropriate start ratio. The control involves sensing engaged transmission ratio (GR) and vehicle speed (OS) to determine if the vehicle is being launched while the transmission is engaged in an inappropriate start ratio and, if such conditions are sensed, issuing command signals to the engine controller (36) to cause engine output torque to be limited to a predetermined value, preferably a value less than 50% of maximum engine output torque.

Abstract: A control for enhanced range shifting in a computer (48) assisted vehicular compound transmission having a main section (16A) shifted by a manually operated shift lever (31) and a range section (16B) shifted in response to operation of a range shift selector, such as sensing shift lever (31) passing through a predetermined actuation point (AR) in the shift pattern. During a compound shift, if the main section is engaged prior to completion of the range shift, the engine is fueled to a synchronous speed for engaging the target ratio (ES=OS*GR.sub.T) and the range section shift is completed without undue wear or damage to the range section synchronized clutch (130).

Abstract: A robust control (10) for a pressurized-fluid-operated, three-position shift actuator piston assembly (12). The system requires only a single controlled source of pressurized fluid (44) to provide movement to and retention in a selected one of three axially displaced positions (D, N, OD). A solenoid-controlled valve (42) is controlled by pulse width modulation. Current applied to the solenoid coil is controlled (46), voltage (V) applied to the solenoid coil is sensed and used as a control parameter and/or a relatively light detent (48, 50) biases the assembly to a neutral (N) position to provide a robust control.

Abstract: A control for enhanced manual shifting in a computer (48) -assisted vehicular compound transmission having a main section (16A) shifted by a manually operated shift lever (31) and an engine fuel controller (36). Engine fueling will be in accordance with the operator-set throttle pedal position (THL) unless the control logic determines that such fueling will prevent acceptable engagement of a target gear ratio (GR.sub.T), in which case engine fueling will be automatically controlled to complete the shift.

Abstract: A control system for controlling jaw clutch (88) engagement for completing upshifts. The synchronous window ((OS*GR.sub.T).+-.offset) for commanding jaw clutch engagement is increased upon sensing relative great vehicle deceleration (dOS/dt<REF.sub.1) or relatively great vehicle acceleration and relative small engine deceleration (dOS/dt<REF.sub.1) and (dES/dt>REF.sub.2).

Abstract: A control for controlling splitter clutch (88) engagement for compound shifts in a controller (48) assisted manually shifted splitter-type vehicular transmission system (10). The controller has logic rule for sensing an attempted compound shift of the splitter-type transmission (16) and will retain the splitter clutch in a disengaged condition (N) until engagement of a main transmission section (16A) ratio from main transmission section neutral is sensed.

Abstract: A control system for controlling splitter jaw clutch (88) engagement and disengagement forces during a splitter section (16B) shift. The splitter section is shifted by a variable force splitter actuator (142) and is preferably capable of asserting at least a low, medium and high force to the splitter jaw clutch members.

Abstract: A control for enhanced shifting in a computer (48)-assisted vehicular compound transmission system having a having a main section (16A) shifted by a manually operated shift lever (31). The system is controlled as a function of current main section engaged or neutral condition sensed as function of shift lever vertical position in an H-type shift pattern. A position sensor (160) is provided for sensing the position of the shift lever in the shift pattern. Logic is provided to vary, as a function of vehicle operating conditions, the location/width of the bands of vertical positions (202/204) considered to be indicative of a main section neutral condition.

Abstract: A control module assembly (200) for mounting as a unit to the housing (116) of a compound transmission (110). The module assembly includes a module housing (202) defining electric (207) and fluid (208) connectors and having an interior containing a position sensor (218) interacting with a transmission shift shaft (188), cavities (212 and 214) defining auxiliary section actuator piston cylinders (204B and 206B), solenoid control valves, a printed circuit board, and various interior electric and fluid conduits.

Abstract: A transmission shifting mechanism (10) and position sensor assembly. The shifting mechanism includes a member (32) of known flux-conducting or flux-insulating properties movable therewith, which will variably extend (42, 44, 46) into an electric coil (36), which is periodically charged and then allowed to discharge. The rate of discharge is variable with the position of the member in the coil and, thus, provides a signal indicative to mechanism condition (H, N, L).

Abstract: A manually shifted, range-type compound transmission (110) is provided with enhanced automatic range shifting. A controller (222) receives input signals indicative of shift lever position in the shift pattern (low range/high range) and of vehicle speed (OS) and automatically commands range shifts as a function of both system parameters.