Abstract: A system for controlling the speed of an engine in a vocational application is implemented within a mobile cement mixer. The system permits operation of the engine at a high rpm PTO speed to drive the mixing drum at a recommended speed for optimal full mixing of aggregate within the drum. The system maintains the engine at this high rpm only for a predetermined time period necessary for full mixing. After expiration of the time period, the system directs the engine governor to drop the engine speed to low idle, thereby preventing overworking of the cement, reducing the abrasive effect of the aggregate on the interior of the mixing drum, and improving engine fuel economy. In one embodiment, the system permits operator entry of drum rotation speed and total drum revolutions, which are then used to calculate the time period value.

Abstract: A road speed control system for a vehicle driven by an internal combustion engine includes a control computer operable to control engine fueling based on inputs from at least an accelerator pedal position sensor, a vehicle speed signal, and at least one control signal. According to one aspect of the invention, the control computer is responsive to a first control signal to decrease the maximum road speed limit value and to a second control signal to increase the maximum road speed value, to thereby provide a road speed limiting system operable under manual engine fueling conditions. According to another aspect of the invention, the control computer is responsive to at least one control signal to activate a maximum road speed limit override feature for temporarily increasing the maximum road speed limit value to, for example, facilitate passing attempts.

Abstract: A vehicle having an internal combustion engine with a throttle control is disclosed. The throttle control is responsive to a vehicle operator to generate a throttle setting signal to adjust vehicle speed. An operator-controlled input device is also provided to generate a selected signal corresponding to a selected one of a number of predetermined engine control relationships. A controller responds to the selection signal to govern engine operation in accordance with the selected one of the relationships and the throttle setting signal. The throttle control has a different performance characteristic for each of the relationships and is adjustable by the operator to increase or decrease speed for each of the relationships. The relationships may each correspond to a different type of engine governing technique and include different droop characteristics.

Abstract: A vehicle having an internal combustion engine with a throttle control is disclosed. The throttle control is responsive to a vehicle operator to generate a throttle setting signal to adjust vehicle speed. An operator-controlled input device is also provided to generate a selected signal corresponding to a selected one of a number of predetermined engine control relationships. A controller responds to the selection signal to govern engine operation in accordance with the selected one of the relationships and the throttle setting signal. The throttle control has a different performance characteristic for each of the relationships and is adjustable by the operator to increase or decrease speed for each of the relationships. The relationships may each correspond to a different type of engine governing technique and include different droop characteristics.

Abstract: A method and apparatus for controlling engine speed during power take-off (PTO) operation. A technique is disclosed which enables accelerator pedal over-ride of PTO operation, wherein PTO operation is resumed when the accelerator pedal induced engine speed value decreases to a preset PTO engine speed. Also, a high-speed governor is employed to limit accelerator pedal-based engine speed during PTO over-ride operation to thereby limit maximum engine speed. In accordance with the invention, the operator of a vehicle can thus accelerate the engine, via actuation of the accelerator pedal, to engine speeds in excess of the preset PTO engine speed without disengaging PTO operation.

Abstract: A cruise control based retarder control. If the vehicle speed exceeds the cruise control set speed, the cruise control system continuously checks the vehicle speed and acceleration order to determine the optimum auxiliary brake level based upon the amount of overspeed and acceleration. The cruise control system allows the vehicle driver to select which auxiliary brakes will be applied to slow down the vehicle to the desired speed by means of the normal cabin brake switches, limited by the determined optimum brake level. The driver can therefore control which auxiliary brakes are applied, however the application of these brakes is controlled by the cruise control system without the need to exit cruise control mode. Operation of the auxiliary brakes by the cruise control system will normally reset in increased fuel economy over prior art systems which require exiting of the cruise control system, manual activation of the auxiliary brakes and resumption of the cruise control system.