Haldexféle

Haldexféle refers to a family of electronically controlled all-wheel-drive (AWD) systems developed by the Swedish company Haldex AB. These systems are designed to provide traction on demand by varying the distribution of torque between the front and rear axles. In normal operation many vehicles employing a Haldex-type system run as front-wheel drive, with the rear axle decoupled until additional traction is required.

Operation and components

The core element is a hydraulic multi-plate clutch that sits in the path to the rear axle. A pump, valves, and an electronic control unit (ECU) actuate the clutch to engage the rear wheels when wheel-slip or loss of traction is detected, or when driving conditions demand extra grip. The ECU interprets signals from wheel-speed sensors and other inputs such as throttle position, steering angle, brake status, and vehicle dynamics to determine the appropriate amount of rear-wheel torque. The goal is to improve stability and traction while minimizing energy use by avoiding permanent AWD torque delivery.

Generations and characteristics

Over several generations, Haldex-féle rendszerek have evolved with improvements in control software, hydraulic actuation, and clutch design. These updates aim to deliver faster, more precise torque transfer and to offer a wider range of torque distribution between front and rear depending on driving conditions. The terminology is widely used in Hungarian automotive literature to describe these Haldex-type, electronically controlled AWD systems found on a variety of front-wheel-drive platforms and adapted to different vehicle models.

Applications and context

Haldex-type systems are used by multiple manufacturers, notably in European-market cars, where they provide an efficient path to AWD without the drawbacks of a permanently engaged center differential. They are one option among several AWD technologies used to enhance traction and stability.