摘要 |
<p>Apparatuses and systems that use a variable displacement motor-pump (VDMP 110) to control the position and speed of a hose for an aerial refueling system are disclosed. At displacements greater than required to hold a position of the hose, the VDMP operates in a motor mode to retract the hose. For lesser displacements, the VDMP operates in a pump mode to control extension of the hose. In accordance with some embodiments, a pump-motor relief valve (112) operates to throttle hydraulic fluid flow from the VDMP and to control mixing of hydraulic fluid flowing from the VDMP with system hydraulic fluid.</p> |