Hy-Power Brake Booster for FMVSS-105 Brake Requirements

In anticipation of hydraulic brake system standards for medium duty trucks requiring dual brake systems and stringent stopping distances, Delco Moraine developed an open-center, hydraulically powered brake booster using the power steering pump as the primary source of power. An electric motor-driven pump is used to provide hydraulic power for the reserve booster system. This Hy-Power brake booster is currently used to actuate a 1-3/4″ diameter high displacement master cylinder.

The total system operation plus operation of the hydraulic booster primary, reserve, and manual modes and respective outputs are described in this report.