Coaxial-rotor helicopter gearbox

FIELD: aircraft engineering.

SUBSTANCE: this gearbox comprises housing to accommodate spinning hollow vertical and coaxial shafts. Rotor is fitted on one end of every said shaft. Sump is arranged in housing case and coupled via bearings and tapered gearing with second ends of hollow shafts of upper and lower rotors. Note here that vaned pump wheel is fitted on upper rotor shaft its vanes being arranged at angle α relative to its radius and provided with orifices arranged regularly on its lower end surface, axes of said orifices being parallel with pump wheel axis. Vanes on sump inner surface are arranged at angle α relative to its radius directed opposite inclination of the vanes of said pump wheel. Chamber case is filled with lubricant and communicated via channel, clearances and orifices with bearings and gearings.

EFFECT: higher reliability.

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The invention relates to the field of aircraft construction and can be used in transmissions, mainly lung coaxial-rotor helicopters.

Known gear coaxial-rotor helicopter Ka-26, contains two concentrically arranged shaft connected to the cylindrical gears internal and external links, kinematically, through bevel gears and couplings associated with the engines of the helicopter (A. Vakhitov Century Helicopter Ka-26. - M.: Transport, 1973, S. 58...65).

However, despite the fact that having a gear oil pump ensures reliable lubrication of the elements of the gearbox under high pressure, known gearbox has a complex structure that requires a complex seal, which significantly reduces the reliability of the device as a whole.

Known main gearbox main rotor, comprising a housing partially filled with a lubricant, drive shaft with a bevel gear meshed with the wheel shaft of the main rotor and the impeller blades and the guide device (Patent No. 2474514 EN. Publ. 10.02.2013,).

However, in known main gear missing the axial bore in the impeller between the shaft and the blades, which creates conditions for oil starvation and heat loss, and is not supplied oil to remote column bearings of the rotor helicopter.

Known GLA is hydrated gear coaxial-rotor helicopter, containing a bevel gear with a pinion meshed with two conical wheels arranged coaxially to each other and connected with two cylindrical gear wheel which is connected with two coaxial and vertically mounted shaft bearing screws (Patent No. 2059535 EN. Publ. 10.05.1996 year).

However, the known invention is complex, large mass, a large number of heavily loaded elements of kinematic pairs, the lubricant which is carried out by the oil pump pressure.

The objective of the invention is the creation of a gearbox of the helicopter coaxial configuration, ensuring reliable operation of the gearing and bearings through the use of simple and reliable lubrication system in conditions of continuous operation on a flying machine, and the result of which is the required speed of expiration and the amount of the lubricant.

The problem is solved in that the gearbox of the helicopter coaxial configuration, comprising a housing within which a vertically and coaxially arranged shafts of the upper and lower screws, are hollow and connected with them, as well as bevel gears, forming a gearing with a bevel gear connected to the cylindrical gear wheel meshed with the leading cylindrical gear, and decree the main shaft is installed with the possibility of rotational movement relative to the housing by means of bearings, on vertically placed the shaft of the upper rotor installed the pump wheel blades, made on its lower surface at an angle relative to its radius and axial holes located between its axis and the said blades, and a sump with a similar inclined relative to its radius in the opposite direction of inclination of the blades mentioned pump wheel, the blades facing into the side of the camera body, filled with lubricating material connected by canal with clearances and calibrated holes, indicating the bearings and the elements of the gearing gears with this camera, in addition, inside the shaft upper bearing screw is placed a sleeve, forming a gap between the inner surface mentioned shaft and the sleeve, forming a channel drain waste oil in the gearbox housing.

The present invention is explained detailed description and drawings, in which:

Fig.1 shows a section of the top view of the gearbox of the helicopter coaxial-rotor vertical plane, according to the invention;

Fig.2 illustrates a cut gear plane a-a (in part).

The engine 1 through the clutch 2 is connected with the shaft and the pinion 3 (Fig.1, 2). Leading gear 3 has the possibility of engagement with the toothed wheel 4 connected with the bevel gear 5, the size of the military in General for her and 4 wheel shaft 6. The specified bevel gear 5 forms meshing with two bevel wheels 7, associated, respectively, with the shaft of the lower rotor (HHB) 8 and the shaft of the upper rotor (auto gaseous VNV) 9. Shafts HHB 8 and auto gaseous VNV 9 have the option of relying on the bearings 10, 11, 12, 13, 14 and 15, mounted in the housing 16. In the lower part of the housing 16 posted the sump 17 with the blades and shaft auto gaseous VNV 9 - related pump wheel 18 with the holes B and the blades facing down (drawing). Blades sump 17 and the pump wheel 18 have inclinations to the radius on the corners, respectively, α and β. Under the blades of the sump 17 in the housing 16 is made Luggage Century. Luggage In through channel G hydraulically connected to the gap D through a calibrated orifice E gap G and, through a calibrated orifice And cavity, formed between the axial hole of the shaft auto gaseous VNV 9 and the sleeve 19, and named the cavity through the openings L communicates with the internal cavity of the housing 16. The latter is supplied by a pipe 20 with calibrated holes M, oriented vertically. The housing 16 of the gearbox is filled with lubricating oil up to level N. Seals 21, 22 and 23 are designed to isolate the cavities and gaps. The magnitude of the gaps D and K, and the diameter of the calibrated holes E, And L are determined considering the required speed expiration Vi and the number podemos the lubricant, it must comply with the condition, characterized by the mathematical expression

G=1000 Ci Ai Vi

where G is the second performance of the pump wheel, l/C;

Ci is the coefficient of hydraulic resistance of the concrete section;

The Ai section to cut an orifice (mm²);

Vi - outflow velocity (m/s);

Z - number of calibrated holes.

Running gear coaxial helicopter schema as follows.

The rotation of the motor shaft 1 through the clutch 2 is transmitted to the conical wheels 7 through gears 3, wheels 4 and bevel gear 5.

Bevel wheel 7 drive shafts HHB 8 and auto gaseous VNV 9 and associated with the shaft auto gaseous VNV 9 pump wheel 18. The oil fed to his blades through the holes B, passes through the blades of the sump 17 into the cavity under pressure, which is sufficient to move the oil through the channels G to the holes M of pipe 20, to the bearing 13 and further through the opening E to the bearing 15 and through the opening to the cavity and then through the opening L merges into the body. Part of the oil through the clearance between the housing 16 and the shaft HHB 8 is supplied to the bearing 12.

The design of the gearbox of the helicopter coaxial configuration allows you to ensure reliable operation of the gearing and bearings through the use of simple and reliable lubrication system in continuous work is on an aircraft.

In the proposed design of all bearings serving rotational movement of the shaft and THUS auto gaseous VNV securely to lubricate and cool the oil contained in the gear housing, which increases the reliability of the gearbox of the helicopter.

In addition, the proposed invention allows to take into account the required rate expires and the amount of supplied lubricant. The amount of oil supplied to the bearings and into the zone of meshing bevel gears, are determined by the values of the cross sections of the gap D and the diameters of the holes E, And L, selected in accordance with the requirements.

The gearbox of the helicopter coaxial configuration, comprising a housing within which a vertically and coaxially arranged shafts of the upper and lower screws, are hollow and connected with them, as well as bevel gears, forming a gearing with a bevel gear connected to the cylindrical gear wheel meshed with the leading cylindrical gear, and these shafts are installed with the possibility of rotational movement relative to the housing through a bearing, characterized in that the vertically placed the shaft of the upper rotor installed the pump wheel blades, made on its lower surface at an angle relative to its radius and axial holes, located is between its axis and the said blades, as well as the sump with a similar inclined relative to its radius in the opposite direction of inclination of the blades mentioned pump wheel, the blades facing into the side of the camera body, filled with lubricating material connected by canal with clearances and calibrated holes, indicating the bearings and the elements of the gearing gears with this camera, in addition, inside the shaft upper bearing screw is placed a sleeve, forming a gap between the inner surface mentioned shaft and the sleeve, forming a channel drain waste oil in the gearbox housing.