Lightweight hydraulic power steering gear

摘要

A lightweight housing (12) for a hydraulic power steering gear (10) includes a tubular structure (34 or 68) with a longitudinal central axis (21 or 23). The tubular structure (34 or 68) has layers extending circumferentially around the axis (21 or 23), including an inner layer (100), an outer layer (102), and an intermediate layer (104) between the inner and outer layers (100 and 102). The inner layer (100) is formed of plastic material. An inner surface (118 or 120) of the inner layer (100) defines an outer boundary of a space (36,38 or 88) containing hydraulic fluid under pressure. The outer layer (102) is formed of metal material. The intermediate layer (104) is formed of elastomeric material, and is compressively loaded radially between the inner and outer layers (100 and 102).