Abstract: A lube spacer bearing for a lube and scavenge pump includes a bearing body defining a bore with a central axis. The bearing body has a first axial side, a second axial side, an outer radial side, and an inner radial side at the bore. The outer radial side includes an arcuate portion. A channel is defined in the arcuate portion of the outer radial side and extends a circumferential length about the outer radial side. The channel has a channel width (CW) defined between a first channel wall and a second channel wall and a bearing length (BL) defined between the first axial side and the second axial side. A ratio of CW/BL is between 0.45 and 0.70.

Abstract: A gear pump comprises first and second gears and a housing. The housing comprises a first arcuate gear bore that receives the first gear, a second arcuate gear bore that receives the second gear, a discharge port that joins the first and second arcuate gear bores, an inlet port that joins the first and second arcuate gear bores opposite the discharge port; and first and second cutbacks that are joined to the first and second arcuate gear bores, respectively, adjacent the inlet port.

Abstract: A hydraulic displacement machine including two external gears located in the machine housing and meshing with each other, with the teeth of the two gears sealingly engaging the inner surface of the housing, and with meshing teeth of the two gears sealing the two port regions from each other, and an arrangement for communicating pressure prevailing in the port region of the housing having a higher pressure to the port region of the housing having a lower pressure over a circumference of each of the two gears.

Abstract: The roller-vane hydraulic machine comprises a hollow casing (1) having working fluid inlet and outlet passages (2, 3). The casing (1) is provided with hollows opening into the space of the casing (1), said hollows accommodating rollers (4) interacting with a rotor (5) located inside of the casing (1). The casing (1) is provided with vanes (6) which, together with the casing (1) form a working space (7) divided by the rollers (4) into larger and smaller inter-roller chambers (8, 9) intercommunicated in pairs by hydraulic relief passages (14, 15). The rollers (4) have slots for the passage of the vanes (6) of the rotor (5). The larger and smaller inter-roller chambers (8, 9) are intercommunicated in pairs by passages (14, 15, 16, 17) in the casing (1).

Abstract: A gear pump in which one rotating, toothed pump gear is supported axially displaceable in the pump casing and engaging an axially displaceable sliding part at least on the one face wall of the pump gear. The sliding part is adapted to overlap the operating space or zone of engagement of the displaceable pump gear against the other, axially stationary pump gear, with hydraulic relief provided by the pump casing and/or the sliding part by pocket-like recesses on the side diametrically opposing the pressure side of the pump across the displaceable pump gear, the recesses hydraulically communicating with the pressure side of the pump.

Abstract: A rotary positive-displacement fluid-pressure motor which includes a casing, having an inlet port and an outlet port, at least two intermeshing rotors of toothed or lobed form housed for rotation in the casing, and means for conducting pressure fluid derived from the inlet port as far as a predetermined position in a face adjacent, and engaged by, a side of one of the rotors. A recess is so disposed in that face intermediate the predetermined position and the outlet port that, for facilitating starting of the motor when fluid under high pressure is directed into the inlet port, some of that fluid can gain access to the recess by way of said means and whichever intertooth or interlobe space of that rotor is so positioned as to place the means and the recess in communication.

Abstract: A reversible gear pump or motor capable of sustained operation under unusually high pressure conditions is provided with a unique diverter plate having pressure-transmitting paths in the ends of the plate which open to the gear teeth on both the high and low pressure sides of the pump or motor. In operation, the high pressure is transmitted through the specially formed paths to areas of the gears on the low pressure side. The pressure acts as a counter force which pushes the gears towards a centered position and reduces bearing loads without increasing the pressure forcing the gears towards one another.

Abstract: Method and apparatus are disclosed for counterbalancing the high pressure forces normally generated in the high pressure fluid region of a rotary pump or motor and exerted against the rotating structure of the pump or motor. By this method and apparatus a portion of the fluid in the high pressure region of the pump housing is transported to a region of the housing interior adjacent to, but out of communication with the low pressure fluid region. This transported high pressure fluid is directed against the rotating structure in the direction of the high pressure fluid region. Consequently, the rotating structure of the pump or motor is less subject to distortion or displacement due to forces generated by fluid in the housing's high pressure fluid region.

Abstract: A gear pump having a drive gear provided with trunions mounted for rotation in the housing of the pump and a driven gear meshing with the drive gear and guided in the housing only on side faces and a portion of the inner peripheral surface of the housing and pressed by fluid pressure against the driven gear. A first sealing member at the outlet of the housing presses the driven gear against a sealing zone of the housing adjacent the inlet thereof and a second sealing member subjected to fluid pressure presses the driven gear against the drive gear. A low pressure zone is arranged at the inner peripheral surface of the housing between the two sealing members, whereas a high pressure zone is arranged between the second sealing member and the sealing zone.

Abstract: An external gear pump wherein the gears are installed in an eight-shaped compartment of a central housing section which is flanked by two covers. The outlet port of the housing communicates with two arcuate recesses for metallic inserts which are biased against the adjacent gears by fluid pressure in the outlet port whereby the inserts urge the gears against those portions of the internal surface of the central housing section which are located opposite the recesses. Such portions of the internal surface are formed with narrow first cutouts which communicate with the outlet port. The internal surface is further formed with relatively wide additional cutouts which are located between the first cutouts and the recesses and communicate with the inlet port. The force which is produced by fluid in the cutouts opposes the force which urges the gears against the internal surface of the central housing section to thus reduce the force with which the stubs of the gear shafts are urged against the housing.