An apparatus and a system for application of pressure to a fluid, as well as a corresponding use. The apparatus includes an introduction port for introducing the fluid into the apparatus; a cooling apparatus port and an outlet port; a controllable first valve device having an adjustable first opening pressure value; a second valve device having a second opening pressure value; a controllable third valve device having an adjustable third opening pressure value; the first valve device and the third valve device being automatically controllable for simultaneous application to the fluid of the first predefinable pressure value for output at the outlet port and of the second predefinable pressure value for output at the cooling apparatus port.

The invention relates to a rotary lobe pump including a pump housing with a pump chamber, an inlet opening and an outlet opening. A first multi-lobed rotary piston is rotably mounted around a first axis in the pump chamber. A second multi-lobed rotary piston is rotably mounted around a second axis in the pump chamber and meshes with the first rotary piston. The first and second rotary pistons are rotated by a drive unit to create a fluid flow from the inlet opening to the outlet opening. The drive unit includes a first electric drive motor mechanically coupled with the first rotary piston and a second electric drive motor mechanically coupled with the second rotary piston.

A fuel pump system for a turbomachine engine can include a boost pump driven by an electric motor and configured to be in fluid communication with a fuel tank, a primary pump configured to be driven by a shaft connected to the turbomachine engine, wherein the primary pump is in fluid communication with the boost pump downstream of the boost pump by a boost branch, a bypass flow branch that connects the boost branch to a downstream branch that is downstream of the primary pump, the downstream branch is in fluid communication with one or more metering valves and/or one or more fuel nozzles, and a bypass valve disposed in the bypass flow branch and/or the downstream branch and configured to selectively directly fluidly communicate the boost branch and the downstream branch.

A method of machining, with a formed tool, a first rotor and a second rotor with mutually complementary meshing threads involves rotating a first workpiece about a longitudinal axis of the workpiece. The tool makes one or more passes along the longitudinal axis of the workpiece as the workpiece rotates so as to remove material, thereby forming the flanks of each helix of the first rotor's thread. The value of at least one of the parameters that collectively define the relative position and relative movement of the workpiece and formed tool is varied during each pass so as to vary the lead of the thread. The above steps are repeated for a second workpiece, thereby forming the second rotor. Adjustments are made to at least one of said parameters during one or more of the passes in order to maintain mutually complementary shapes of the threads of the rotors.

Provided is an internal gear pump. The shape of any one of a plurality of external teeth and a plurality of internal teeth of the pump is formed on the basis of formulae (1)-(5). Formula (1): r=ro−dr.Math.cos θ, Formula (2): Px=(ro−dr)+1/4 dr{1−cos (2θ)}, Formula (3): Py=1/4 dr{−2θ+sin (2θ)}, Formula (4): Qx=Px−r.Math.cos θ, Formula (5): Qy=Py+r.Math.sin θ.

A gear pump (1) comprises a pump housing (2), wherein a working chamber (6) is formed in the pump housing (2). A first gearwheel (11) and a second gearwheel (12) are arranged meshing with each other in the working chamber (6). The first gearwheel (11) has a number of first teeth (13) and the second gearwheel (12) has a number of second teeth (14). A first tooth flank (13a, 14a) and a second tooth flank (13b, 14b) are formed on each of the teeth (13, 14). When the gearwheels (11, 12) mesh, the first tooth flanks (13a) of the first teeth (13) are meshed with the first tooth flanks (14a) of the second teeth (14). A coating (15) is arranged on each of the first tooth flanks (13a, 14a). The coating (15) and the first tooth flank (13a, 14a) are positively connected to each other.

A liquid gear pump includes a gear pump assembly and an electric motor with an motor shaft. The gear pump assembly includes a pump housing which defines a pump chamber, an inlet and an outlet which are in fluid communication with the pump chamber, and a driving gear and an idle gear which are received in the pump chamber. The driving gear is driven by the motor shaft. The idle gear is supported on an idle shaft and engaged with the driving gear. The driving gear and the idle gear are made of a material with a main component of PPS.

An internal gear pump for a slip-controlled hydraulic vehicle braking system includes a pump shaft that is mounted rotatably on one side of a pinion and a ring gear that is mounted rotatably in an axial disk. The axial disk seals off the pinion and the ring gear at the sides.

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.

A gear for a pump includes a gear body defining a root circle, and a plurality of gear teeth extending from the gear body radially outwardly of the root circle. Each of the plurality of gear teeth have a tip portion, a leading edge, a trailing edge, a circular thickness defined between the leading edge and the trailing edge, a first radially outwardly facing surface and a second radially outwardly facing surface. At least one of the first radially outwardly facing surface and the second radially outwardly facing surface includes a chamfered portion that extends from the leading edge toward the trailing edge across a portion of the circular thickness.