| 摘要 |
An integral power steering gear with a valve in the piston is provided having a short piston and cylinder to conserve space and weight. The input shaft is mounted on a bearing carried by an inwardly projecting annular portion on the bearing cap. The projecting portion mates with a recess in the end of the piston when the piston is moved to the full extreme in that direction. The valve guide pin has been relocated at the input shaft end of the valve where maximum support of the valve is realized and improved reversibility of the valve under all conditions is gained. In the bearing cap, both a high pressure seal and a low pressure weather seal are provided. An insert ring between the two seals serves as backup to the high pressure seal. In an alternative embodiment, the insert ring may be tapered toward the inside of the gear to allow use of a thin wiper-type seal. Lubricating grooves in the piston adjacent the output rack provide fluidized bearings to counteract the force of the fluid bearing provided on the top of the piston at the pressurized input slot. Dual feed passageways extending to opposite ends of the piston have connecting ports drilled from opposite sides of the piston to add further lubrication, but also prevent cross-bleeding between the ports. |
