Abstract: A vane pump having a flow regulating bypass valve activated by outlet pressure to direct excess flow back to the inlet is provided with a channeling having an element comprising a plug insertable in the valve housing, which plug has a specially shaped flow bend in the form of an arcate groove that forms a smooth transition for combined flow from a tank fed inlet and from the bypass valve to the pump inlet. This is effected by connecting a channel from the tank inlet and bypass valve to a channel for flow return to the pump inlet which channels are angularly related. Since the valve housing is die cast the difficulty of providing, in a casting, an exactly shaped smooth surfaced and accurately dimensioned transition passage between the aforementioned channels is overcome by the invention.

Abstract: At least two radial piston pumps having a common eccentric rotatable within an eccentric chamber of the pump housing supply pressurized fluid to separate fluid circuits. The eccentric chamber is divided into separate fluid delivery compartments to which fluid is conducted from a common suction port by the pumps through passages that dampen the transfer of pressure fluctuations between the fluid circuits.

Abstract: A mode of assembly for a vane pump rotor and drive shaft provides a construction wherein a plain, i.e., sleeve or collar type bearing can be used for the support of the drive shaft. The arrangement affords axial positional securing, i.e., axial fixation of the drive shaft with a spring ring peripherally confined by a recess in the pump rotor to prevent its being dislodged and thus affording safety in maintaining axial securement of the drive shaft.

Abstract: A particular composition and method are given for an iron alloy which will produce an article by sintering which is highly resistant to abrasion as well as possessing high tensile strength. The alloy is particularly useful for bearings, either rotary or planar. Conditions of sintering are described to produce articles from a novel sintering powder having a homogenous carbide network in a lamellated, perlitic base structure with interspersed residual austenite and martensite to considerably improve the abrasion resistance.