| 摘要 |
<p>1,224,566. 566. Hydraulic gear pumps. KOEHRING CO. April 30, 1968 [Dec.27, 1967], No.20456/68. Heading F1F. A hydraulic gear pump comprises a casing 5, Fig. 1, having a pair of parallel intersecting bores 19, Fig. 2, rotatably mounting intermeshing gears 15. The gears are mounted on drive and collar shafts 11, 12 between front and rear bearings 23, 24 having flanges 21, 22 closely fitting the bores, and means to radially balance the hydraulic forces acting on the bearings. Chambers 25 behind the rear bearings 24 to which pump discharge pressure is admitted urge the bearings and gears into sealing engagement with each other. In one embodiment, holes 35, Fig. 2, are drilled axially through the rear bearings 24 to connect the chambers 25 to root spaces between the gear teeth on the inlet side of the pump to transmit pump discharge pressure thereto. The holes are located on radii through the bearing axes which are spaced about 30 degrees outwardly of the horizontal planes through the axes and are tapered in width and depth towards the pump inlet. Drive shaft seal 42 is located in a mounting member separate from the casing 5 so that it may be replaced if necessary without dismantling the pump. In another embodiment a peripheral chamber 38, Fig. 5, extends in the front face of either or both bushes from the pump outlet towards the pump inlet and a groove 39 parallel to but offset from a plane common to the gear axes connects the chamber to the root circle of the teeth at a location where there is one tooth between the end of the groove and the pump inlet.</p> |
