Abstract: A pump and motor assembly (20) includes a centrifugal pump (30), a bent axis hydraulic pump 58, and a wet-type drive motor (228). The motor has a rotor and a stator that are submerged in hydraulic fluid for full lubrication and cooling. A drive shaft 66 is driven by the motor. The centrifugal pump has a rotatable impeller (50) for pumping hydraulic fluid from an inlet (48) to the bent axis hydraulic pump. The centrifugal pump also pumps fluid to the motor for lubrication and cooling. The bent axis hydraulic pump pumps the fluid and discharges the fluid from the system. The centrifugal pump and the bent axis hydraulic pump are rotatable along a common rotational axis R1 that is angled relative to the rotational axis R2 of the drive shaft.

Abstract: A pump assembly includes a housing, and first and second rotor that are rotatable within the housing and mesh with each other. The pump assembly includes wear plates arranged on opposing sides of the rotors and a separation mechanism that is engageable with the wear plates and enables axial movement of the wear plates relative to the rotors. The wear plates are normally biased to be disengaged from the rotors and axially moveable to engage the rotors when pressure in the pump assembly exceeds a predetermined pressure threshold. The rotors may be lobe gears that each include a plurality of lobes. The lobes may include wiper retaining recesses that retain wiper inserts and the walls of the wiper retaining recesses may have pressure trapping grooves that enable trapped fluid to flow out of the wiper retaining recesses for pressure relief.

Abstract: A high speed, rotary lobe gear pump assembly is provided which combines a positive displacement lobe gear pump having wipers with a centrifugal pump utilizing an impeller. The centrifugal pump feeds high pressure fluid flow directly into the lobe gear pump allowing the gear pump to rotate at high speeds without cavitation. The high speed capability of the pump assembly allows the lobe gear pump to operate without speed reduction gearing for the motor shaft.

Abstract: A pump and motor assembly (20) includes a centrifugal pump (30), a bent axis hydraulic pump 58, and a wet-type drive motor (228). The motor has a rotor and a stator that are submerged in hydraulic fluid for full lubrication and cooling. A drive shaft 66 is driven by the motor. The centrifugal pump has a rotatable impeller (50) for pumping hydraulic fluid from an inlet (48) to the bent axis hydraulic pump. The centrifugal pump also pumps fluid to the motor for lubrication and cooling. The bent axis hydraulic pump pumps the fluid and discharges the fluid from the system. The centrifugal pump and the bent axis hydraulic pump are rotatable along a common rotational axis R1 that is angled relative to the rotational axis R2 of the drive shaft.

Abstract: A high speed, rotary lobe gear pump assembly is provided which combines a positive displacement lobe gear pump having wipers with a centrifugal pump utilizing an impeller. The centrifugal pump feeds high pressure fluid flow directly into the lobe gear pump allowing the gear pump to rotate at high speeds without cavitation. The high speed capability of the pump assembly allows the lobe gear pump to operate without speed reduction gearing for the motor shaft.

Abstract: A centrifugal pump for a fluid tank includes a pump housing enclosing an electric motor, a primary impeller coupled to the drive shaft of the motor, and a secondary impeller extending axially downward from the primary impeller proximate to the floor of the tank. The secondary impeller has a central stem and helical blades formed integrally with the stem and extending radially outward therefrom. An outer shroud encloses the central stem and helical blades of the secondary impeller. The outer shroud is fixedly secured to the helical blades and rotates in conjunction with the secondary impeller. The secondary impeller is either formed in one piece with the primary impeller or is removably attached by, e.g., screwing a threaded shaft on the secondary impeller into a corresponding through-bore in the primary impeller and the motor drive shaft.