TRW Automotive Unveils Second Generation Slip Control Boost for Hybrid and Low Vacuum Braking Systems

LIVONIA, Mich., October 16, 2008: TRW Automotive Holdings Corp. , through its Kelsey-Hayes Company subsidiary, is developing its second-generation Slip Control Boost 2 (SCB 2) brake technology ideal for regenerative and low vacuum powertrain vehicles.

Slip Control Boost 2 offers the same fully integrated TRW stability and brake actuation functions as the original system and replaces traditional boosters, master cylinders and vacuum pumps with a 25% smaller and lighter electro-hydraulic control unit (EHCU). SCB2 also uses a brake pedal simulator unit with a twin master cylinder to supply brake pressure. The twin master cylinder has been significantly reduced in length when compared to the original system.

"Slip Control Boost technology solves a number of challenges for the requirements of current and future brake systems," said Josef Pickenhahn, vice president, braking systems for TRW Automotive. "Our original Slip Control Boost is already in production on GM's Chevrolet Tahoe and GMC Yukon hybrids and works seamlessly with the two-mode regenerative system. And with the higher penetration of direct injection and diesel engines globally, Slip Control Boost 2 and its predecessor can generate high pressure in the absence of significant vacuum power for these powertrains."

"As the hybrid and direct-injection engine vehicle market continues to grow, TRW stands ready to assist our customers with flexible systems that meet the requirements across the broad range of engine variants for vehicle platforms," said Peter Lake, executive vice president, sales and business development, TRW Automotive. "Fuel efficiency, packaging flexibility and weight reduction are key factors, and in the case of the second generation Slip Control Boost, we can offer regenerative energy recovery with full Electronic Stability Control functionality in a smaller, lighter package."

TRW alternative powertrain brake solutions

TRW offers two brake system solutions for hybrid and other alternative powertrain vehicles, the Slip Control Boost system family (SCB and SCB 2) and the Electronic Stability Control Regenerative (ESC-R) system.

The SCB family of systems incorporate high performance Electronic Stability Control and brake actuation within a 12- volt system architecture. This offers several advantages: (1) ease of installation with fewer components to fit; (2) improved packaging in the front dash area versus traditional vacuum boosters; (3) a decoupled brake pedal that is ideal for integration into autonomous or emergency braking systems; and (4) best-in- class NVH characteristics.

The ESC-R is a modular, hydraulically closed system based on TRW's Standard Electronic Stability Control system with a conventional booster and master cylinder, a vacuum pump, if required, and a brake volume displacement simulator. This system configuration results in no change in pedal feel from traditional brake systems and a seamless blending of regenerative and hydraulic brake output based on driver demand.

The ESC-R system makes maximum use of standard actuation and ESC components and works within a 12 volt power system to offer both safety and fuel savings benefits and is compatible with four-wheel drive, rear wheel drive and front-wheel drive vehicles.

The systems can cover a range of vehicles from small cars to Sport Utility Vehicles.