Navistar unveils camless engine technology
7 April 2000
International Truck and Engine Corporation (operating company of Navistar International Corporation) demonstrated a camless diesel engine technology, which has been designed to address future emissions standards while improving engine performance.
Dan Ustian, president of the company's engine group, said "Our camless engine technology represents a radical change in the way engines operate, and we are pleased to be the first to demonstrate an operational camless diesel in a truck. We believe applying this technology to air management in diesel engines is the inevitable step to meeting customer and environmental needs."
Ustian spoke to a group of editors and reporters at the company's Melrose Park, IL, technical center and engine plant. He said that the International continues to refine its camless technology and expects to have a camless engine in the marketplace within three or four years.
According to Ustian, the camless technology expands upon the company's electro-hydraulic platform, and uses electronics to control valve timing in place of a conventional mechanical camshaft and push rod assembly. He said International® camless engine technology has been under development by the company and Sturman Engine Systems, LLC since the formation of a joint venture in 1995.
International camless engine technology was demonstrated to the media in an International 8100 truck with an International 530E diesel engine. International is now able to control air to and from the engine without the limitations imposed by a mechanical system of cams and levers. Instead, International camless engine technology uses electronics and hydraulics to actuate the valves. Based on extensive testing, the benefits of International camless engine technology include:
- Driveability - the camless engine technology has shown to provide up to a 40% increase in torque at clutch engagement speeds, which means a flatter torque curve resulting in smoother acceleration and faster starts. In addition, the camless engine concept will allow integration of compression-braking technology in the engine design, providing greater control over deceleration and wheel brake wear for customers who choose that option.
- Reliability/Durability - the camless engine technology creates the ability to control valve-seating velocity. When the rate of closing is controlled with hydraulic actuation, the valves compress gently, increasing parts reliability and creating less noise. Integrated compression braking technology will lessen brake wear, reducing maintenance costs and improving uptime for International trucks. Solid-state electronic controls also increase reliability because they are wear resistant, easier, and faster to diagnose when compared to mechanical systems, increasing the overall lifecycle value of the engines. Additional weight is eliminated because the optional compression brake is incorporated in the engine design, as opposed to most current compression brakes, which are add-on devices. Additionally, electro-hydraulic air management technology provides another engineering tool to meet future emissions standards.
International has been in the engine business for nearly 100 years. The company currently is field testing its International Green Diesel Technology™, which uses a regenerative particulate trap and low-sulfur fuels to dramatically reduce particulates and help eliminate offensive odors and fumes.
Source: Navistar International Corporation