| 摘要 |
An Emergency or back-up Hydraulic System for use with a primary hydraulic system in motor operated equipment is disclosed. The system illustrated is a steering system for a vehicle and includes a motor driven pump and a wheel driven pump for supplying hydraulic fluid to the steering system of the vehicle. The motor driven pump and the wheel driven pump are connected in series so that the fluid discharged from the motor driven pump is supplied to the inlet of the wheel driven pump. The inlet of the wheel driven pump also communicates with the reservoir as for example through the anticavitation check for the engine driven pump. By-pass connections are provided around the wheel driven pump so that fluid in excess of the demands of that pump are channelled to the steering circuit when the engine driven pump is in operation. The system disclosed provides that the demands of the wheel driven pump are met by the engine driven pump and/or the reservoir depending upon the relative speeds and capacities of the engine and the wheel driven pumps. The system disclosed is flow limiting so that the steering or other hydraulic system is not overwhelmed when both pumps are in operation. |
