1482 results about "Jet engine" patented technology

A VTOL aircraft (or other vehicle such as a sea vehicle) includes a pair of elongated ducts on opposite sides of the vehicle body, and a plurality of powered propellers (or other propulsion units such as jet engines) mounted within and enclosed by each of the elongated ducts, such as to produce an upward lift force to the vehicle. Each of the elongated ducts has a short transverse dimension slightly larger than the diameter of the blades of each propeller enclosed thereby, and a large transverse dimension slightly larger than the sum of the diameters of the blades of all the propellers enclosed thereby.

The invention discloses a gear pump used for a microminiature turbo-jet engine, comprising a direct current motor, a pump body, an upper pump cover, a lower pump cover, a shell, a pair of driving and driven gears which are meshed and a driving shaft and a driven shaft. The driving gear is arranged on the driving shaft; the driven gear is arranged on the driven shaft and is aligned and meshed withthe driving gear; the lower pump cover is fixed on the direct current motor, the upper pump cover is connected to the lower pump cover and the plane of the pump body is pressed tightly and sealed so as to lead the structure to be simple; the shell is sleeved at the outside of the lower pump cover; the driving gear and the driving shaft adopt a method of combining clearance fit and a transmission pin to eliminate the installation error of an output shaft of the direct current motor; and an antifriction material is embedded at the positions on the lower pump cover and the upper pump cover corresponding to the driving gear and the driven gear so as to increase the reliability and durability of the gear pump. Most parts of the gear pump adopt aluminium alloy so as to reduce the weight furthest. The gear pump can control the rotating speed of the direct current motor by pulse-width modulation of a single-chip microcontroller and control the flow rate of the gear pump precisely.

Noise reduction sandwich panel, notably for an aircraft turbojet engine.In order to produce a noise reduction sandwich panel having a structure with two degrees of freedom, inserted separative components (20) are placed into the hexagonal cells (16) of the unique waffle core of the panel. More specifically, the separative components (20) have an substantially circular external peripheral edge, which allows them to be easily assembled, in spite of the deformations of the walls (18) of the cells (16) due to manufacturing tolerances and to the optional forming of the waffle core. Advantageously, several separative components (20) are supported by a same positioning unit (22), which then allows relative displacement between the separative components.

An artificial grass surface (10) suited for bordering a runway (12) of an airfield in order to reduce the presence of birds in the airfield. The artificial grass surface (10) includes a pile fabric (14) having a plurality of pile elements (20) extending from a backing mat (18) and resembling grass. A water barrier (24) is provided for preventing water from percolating to the compacted soil surface. An infilled particulate material (22) is dispersed among the pile elements (20). A stabilizer is provided to resist dislodgment of the infilled particulate material (22) at the edges of the runways by the thrust of jet engines and to keep the particulate material (22) in the pile elements (20) when the edges of the runways are vacuumed to remove silt.