Phoenix International Corporation

Charles D Needham

Barry Douglas Batcheller

Kevin L Brekkestran

Adrian G Kallis

An electronic transmission control system for a self-propelled off-road vehicle having an internal combustion engine and multiple gear powershift transmission controls the powershift transmission and provides the at least on control signal to the engine for selecting the speed at which the engine is to operate. The system preferably includes a first electronic controller that provides transmission control signals required to command the powershift transmission to shift to and operate in any particular one of its forward gears, and a second electronic controller that provides at least one engine control signal required to command the engine to operate at one of a number of different desired engine speeds and to monitor the actual engine speed. By use of gear ranges which overlap slightly, and a throttle that is infinitely adjustable within a range of engine speeds, any given ground speed within the range of possible vehicle speeds can be achieved and maintained, as long as the engine is operating within its overall power envelope. The system also supports a pseudo-gear mode where the operator interface indicates there are more gears in the transmission than actually exist.

Pseudo-gear transmission control system and method

An electronic transmission control system for a self-propelled off-road vehicle having an internal combustion engine and multiple gear powershift transmission. The control system controls the powershift transmission and provides at least one control signal to the engine for selecting the speed at which the engine is to operate. The system includes a first electronic controller that provides transmission control signals required to command the powershift transmission to shift to and operate in any particular one of its forward gears, and second electronic controller that provides at least one engine control signal required to command the engine to operate at one of a number of different desired engine speeds and to monitor the actual engine speed. By use of gear ranges which overlap slightly, and a throttle that is infinitely adjustable within a range of engine speeds, any given ground speed within the range of possible vehicle speeds can be achieved and maintained, as long as engine is operating within its overall power envelope. Once the desired ground speed is specified by the operator, the control system automatically selects the specific transmission gear and engine speed required to achieve the desired ground speed. The control system also performs automatic upshifts or downshifts, as required, to achieve the desired ground speed. The system has a comfort mode, fuel economy mode, and a maximum horsepower mode, all selectable by the operator. The system also supports a pseudo-gear mode where the operator interface indicates there are more gears in the transmission than actually exist.

Engine variable transmission control system

An expandable, modular microcomputer system for an off-road vehicle having a controller which is operable to generate a plurality of independent pulse-width modulated control signals and a plurality of independent on/off control signals to a corresponding plurality of metal oxide silicone field effect transistors (MOSFETS). An RS-485 bi-directional serial communications interface enables the system to communicate with at least one other ingredient, external, controller. Thus, the control system can be modularly expanded to handle the needs of increasingly complex powershift transmissions. A watchdog circuit monitors operation of the controller and is supplied with a regulated voltage independent of the regulated voltage used to power the microcomputer. The watchdog can provide a reset signal to the microcomputer when spurious operation of the microcomputer is detected, as well as initiate operation of a back-up voltage supply circuit. The back-up voltage supply circuit is responsive to at least one analog input and operable to pulse-width modulate at least one of the MOSFETs to thereby control a clutch of a powershift transmission while operating in a 'limp-home' mode. The system is particularly well-suited for controlling transmissions of heavy-duty off-road vehicles such as earth moving and other like vehicles, but can be readily adapted for use with transmissions of vehicles to be used to widely varying applications.

Growing community of inventors

Fargo, ND, United States of America

Charles D Needham