FOR THE fourth consecutive year, Eaton Corporation has expanded its family of Eaton Fuller AutoShift transmissions to include a line of seven-speed AutoShifts for regional carriers and LTL markets. They are available with maximum torque ratings of 1150-lb/ft and 1450-lb/ft. Like the new six-speed AutoShifts, the seven-speed includes a "ball-ramp" technology inertia brake for fast upshifts.
According to Diane Foppema (medium-duty) and Mark Osinski (heavy-duty), product and market development managers, the newest additions include the same advanced logic, fuel economy, performance, and driver-friendly features of previous AutoShift transmissions. Furthermore, the seven-speeds communicate with a vehicle's engine via the J-1939 data link and include AutoShift "Generation 2" enhancements, such as improved connectors and upgraded circuitry, which significantly expands the products' self-diagnostic capabilities. The seven-speed is an Eaton-Fuller twin countershaft transmission with progressive ratios, which are more advantageous for city driving. The progressive ratios require less shifting in the lower gears while maintaining close steps at the top end for improved fuel economy.
"We're convinced that the new seven-speed AutoShift transmissions will bridge the gap between the lower and higher horsepower and torque requirements that are currently emerging in a variety of applications," said Osinski. In addition to markets that include vehicles involved in regional hauling and LTL hauling, applications such as dump operations, roll-off, refuse, beverage hauling, and municipal operations are good fits for the seven-speed.
The AutoShift seven-speed transmissions weigh roughly 611 pounds without clutch and have an overall ratio of 12.35:1. The TO-11607B-ASX model has a torque range of 860 to 1150-lb/ft, with the TO-14607B-ASX model coming in at 1150 to 1450-lb/ft.
The "shift-by-wire" technology of AutoShift transmissions offers medium- and heavy-duty customers the convenience of automatic shifting, with the durability and efficiency of a manual transmission, Foppema said. Manual lever shifts are eliminated. The clutch is required only when starting or stopping the vehicle. Once the truck is in motion, shifting is fully automatic.
The reduced physical and mental workload offered by AutoShift has been proven to reduce driver fatigue for safer vehicle operation. Meanwhile, computer-controlled shifting optimizes vehicle performance and fuel economy.
With AutoShift, electronic controls and electromechanical actuators take the place of the manual shift lever. Sophisticated, proprietary software algorithms allow AutoShift to function like an expert driver to make smooth and accurate shifts. AutoShift's on-board computer monitors vehicle speed, engine speed, throttle input, and initiates shifts automatically at the appropriate shift points to maximize vehicle efficiency and performance.
Standard on the new seven-speed AutoShift transmissions is an inertia brake with exclusive Eaton "ball-ramp" technology. PTO options include a right-side, six-bolt opening and two optional extended countershaft openings, with both gears turning at .513 of engine speed. The inertia brake occupies the left side eight-bolt PTO opening.
An electromagnetic retarder (12- or 24-volt) is also under development with Jacobs Vehicle Systems for the seven-speed ASX. The retarder fully integrates with all AutoShift transmission functions, as well as cruise control, antilock braking, and Eaton Vorad Collision Warning Systems. No modifications to the driveline and no additional cooling are required for installation. The retarder has an 1800-ft/lb capacity and weighs 481 pounds.
Limited quantity production runs began in January for the 7-speed. With evaluation currently underway with most North American truck and bus manufacturers, full production is expected to begin in June 2000 for the 7ASX.