FI79886B - FOERFARANDE FOER AOSTADKOMMANDE AV HELIKOPTERNS MOTORSYSTEM. TRANSFERRED PAEIVAEMAEAERAE-FOERSKJUTET DATUM PL 14 ç 27.04.88. - Google Patents

Description

Method of implementing a helicopter powerplant - Förfarande för ästadkommande av helikopterns motor- system 79836

The invention relates to a method for implementing a helicopter power plant.

The advantage of a reaction force device placed on the blade (tip) of a helicopter rotor (e.g. a dam tube motor or a jet nozzle to which pressurized gas is led along hollow blades from a compressor in a helicopter fuselage) is that almost no torque is transmitted from the fuselage to the rotating rotor. In this case, complex transmission and tail rotor systems are unnecessary and the helicopter is simple and lightweight in structure. Due to the poor efficiency of the power plant complex, this so-called jet rotor helicopter is not very common today.

The invention relates to methods and devices in which the helicopter is powered by a free piston engine and a reciprocating compressor connected thereto, the compressed air produced by which is led to the hollow rotor blades and the nozzles therein. A similar method is known from U3 patent publication 2,590,457, in which a compressor piston is in close connection with the piston of a 2-stroke engine. The compressed air produced by the compressor is used to purge the 2-stroke engine and the engine exhaust is led to the turbine and further to the rotor blades. Em. the turbine drives a turbocharger, the compressed air produced by which is also led to the hollow rotor blades. The publication mentions that a 2-stroke engine with reciprocating compressors may be of the free piston type.

The invention of this application is considerably simpler; the turbine and turbocharger are not used, which allows for a relatively good efficiency of the jet rotor helicopter. The power unit is also simple and light. To achieve this, the methods according to the invention are characterized by what is stated in the features of the main claim. Other features of the invention will be apparent from the subclaims.

In the following, the invention will be explained with reference to the accompanying Figures 1, 2, 3 and 4. The designations in the illustrations and text are: 1 rotor blade 2 nozzle 3 compressed air 4 compressor intake port 5 compressor outlet valve 6 engine exhaust port 7 engine piston 8 engine flush piston 9 engine intake port 10 seal 11 baffle plate 12 rotor hub 13 compressor piston 14 compressor intake valve 15 compressor intake valve filling chamber 17 throttle / valve 18 flexible diaphragm (eg rubber) 19 non-return valve 20 start valve 21 pressure tank 22 carburettor / fuel supply device 23 pressure line 24 fuel tank 25 connecting rod 26 compression chamber 27 workspace 3 79836

In Figure 1, the power unit is a Stelzer motor (known from DE OS 3 029 287 (F 02 B 71/00)), on which both compressors are built. The compressor includes e.g. parts 4 and 5. The piston 7 of the compressor is the piston 7 of the Stelzer motor. When the motor is running, the assembly formed by the pistons 7 and 8 swings back and forth and in the extreme position of the pistons the suction openings 4 are open and The compressed working fluid air exits the compressor through the directional valves 5 and is led to a rotating rotor hub (hollow) 12 (a seal 10 is required) and further along the hollow blades 1 to nozzles 2 from which the compressed air 3 discharges into the environment causing rotor rotation.

The nozzles 2 can be nozzles with a decreasing or decreasing flow cross-sectional area and then expanding (so-called Laval nozzle). The nozzle may be located at the tip of the blade or may cover a larger area of the blade (e.g. the trailing edge) and the jet may be used not only to generate the torque required to rotate the rotor but also to generate circulation (control its intensity) / control blade lift / limit layer control, etc.

The rotor can be of the rigid type (as in Figure 1) or of another type, e.g. a semi-rigid or articulated rotor.

The powerplant with its compressors may be located in the helicopter fuselage (as in Figure 1) or it may be located in the rotor hub (with wheels).

The suction opening 4 may be replaced by a suction valve commonly used in compressors (directional valve in the compressor cover).

There may be two or more power units with compressors in the helicopter (for added safety).

4,79836

The exhaust gases discharged from the exhaust port 6 can be mixed with the compressed working fluid air 3, whereby a higher volume flow (low pressure) is obtained. The other extreme is high pressure (only air 3 as the working medium) and the use of a Laval nozzle. It is possible that only the exhaust gas is used as a working medium to be fed to the nozzles 2 (Stelzer engine only without compressor). The compressor can be separate from the Stelzer motor (connected to the Stelzer motor via a pull-to push rod).

Instead of a Stelzer motor, it is also possible to use a power unit / compressor according to Figure 2, in which the pistons 7 of the 2-stroke motors located at both ends are connected to the piston 13 of the compressor. The 2-stroke motors operate like a normal 2-stroke motor; however, the crankshaft and crankshaft are missing and are a free piston engine. The engine can run on a petrol / positive ignition engine or a diesel engine. The piston 13 and the compressor can be left out (there is a partition between the 2-stroke engines) when only the engine exhaust is fed to the rotor. In Figure 2, the suction opening 4 may be replaced by a suction valve (directional valve) in the cylinder head.

Since the power of the freewheel motor can be quickly adjusted if necessary, the circulation of the blade can also be quickly adjusted (when the purpose is not only to rotate the rotor but also to influence the circulation). In this case, the rotor closing joint (setting angle adjustment) can be omitted. In this case, it is possible to use, for example, a 2-blade rocker rotor (one flutter joint) known from autogyroes; cyclic steering by tilting the shaft and pitch control by adjusting the engine power.

Turbocharger technology (to recover exhaust energy and / or reduce the suction flow of a reciprocating compressor) can be used with the engines and compressors of this application.

5,79836

In Fig. 3, the main principle is the same as in Fig. 2. At both ends of the power unit there are 2-stroke engines (parts 6, 7, 9 and 22, diesel engine also possible), the pistons of which are connected by a part 25 to which the compressor pistons 13 are attached. The seals are (rubber) diaphragms 18, but other seals can be used (e.g. a rolling diaphragm seal or a normal piston ring). The air to be compressed is taken from the outside through the directional valve 14 and exits the compression space via the directional valve 5. This device is suitable when the pressure ratio is lower and the required stroke volume flow is high. It is possible to make the pressure drop in the valves small. There can be 1 piston 13, in which case all valves must be placed on the cover.

Start-up can take place with compressed air (pressure vessel 21). The (solenoid) valves 20 can be controlled by the ignition circuit breaker and high pressure air can enter the combustion chamber when the piston 7 is close to its top dead center. If the piston is not sufficiently far to the extreme position before starting, manual control of the valves 20 can be used to initiate the starting event. Combustion gas cannot pass through the directional valve 19. Excessive movement of the piston is prevented, for example, by a microswitch, which the piston 13 begins to touch, temporarily switching off the ignition. The piston 13 may also begin to contact a valve that releases pressurized air to a device that adjusts the power from the carburetor less. The ignition can also be adjustable according to the power / piston extreme position.

In Fig. 4, the free piston engine operates on the 2-stroke principle so that in the second extreme position of the piston 7 the filling port 15 and the exhaust port 6 are open (the piston is not at them) and the fuel and air mixture (only air in the diesel engine) enters the cylinder and the exhaust gas escapes. In the extreme position of the piston, the air inlet 4 (there may be several to reduce the flow resistance) is open and the vacuum draws air into the compression space. Instead of the inlet 4, 6 79836 may have a non-return valve, as in the compressor in general (on the cover). The compressed air 3 leaves the compression space via a directional valve 5 (there may be several) to be fed to the rotor. A part of the compressed air 3 is used as combustion air of the internal combustion engine, possibly by mixing fuel with it (e.g. by a carburetor 22; the throttle 17 may be a part belonging to the carburetor). The air is led through the filling opening 15 to the working cylinder. The storage chambers 16 ensure adequate filling and equalize pressure fluctuations. A choke 17 may be necessary before the storage chamber. Since the carburetor 22 is pressurized, it may be necessary to pressurize the fuel tank 24 (pressurization line 23). As shown in Figure 4, the power unit has almost all parts in two pieces and is symmetrical. Possible igniters and starting system (e.g. compressed air) are missing from Figure 4. It may be necessary for opening 15 and / or 6 to open considerably before the piston is at its lower dead center.

Claims (10)

A method of obtaining the engine system of the helicopter, in which process gas (3) is pressurized through hollow helicopter rotor blades (1) to nozzles (2) located in the rotor blades to provide the reaction torque needed to rotate the rotor and / or for effecting the circulation or boundary layer of the rotor blade, characterized in that the pressurized gas (3) is produced by a static piston compressor, the piston of which is a piston engine piston (7, Figs. 1 and 4) or a compressor piston (13, Fig. 2 and 3) which is in fixed communication with a piston engine piston (7). 2. A method according to claim 1, characterized in that the free-piston motor consists of two cylinders (2, 3 and 4) located opposite each other, the pistons (7) of which are fixedly connected to each other with a spacer (25). Method according to claim 2 (Fig. 4), characterized in that the filling and flushing of the 2-stroke engine is carried out with air compressed with a piston compressor or with a mixture (3) (Fig. 4) of air and fuel which is fed to the engine. cylinder via a filling chamber (16) and a filling opening (15). Method according to claim 2 or 3, characterized in that the pistons (13) of the compressor (Figures 2 and 3) are fixed to the spacer bar (25). Method according to claim 2 or 3 (Fig. 4), characterized in that the air (3) is compressed with the pistons of the 2-stroke engine (7) so that the compression chamber (26) is on the opposite side of the cow (7) with respect to the working position. chamber (27). 6. A method according to claim 1, characterized in that the pressurized air (3) directed to the nozzles (2) is produced by a compressor, the piston of which is in fixed communication with the moving parts of the Stelzer motor (7, 8, FIG. 1) and move with them. Process according to claim 6, characterized in that the piston of the compressor (3) producing the compressor S is a piston of a Stelzer motor (7, Fig. 1). 8. A method according to claim 6 or 7, characterized in that the pressurized gas (3) supplied to the nozzles (2) consists of a mixture of air and the exhaust gas of the Stelzer engine compressed with a compressor. 9. A method according to claim 1, characterized in that the pressurized gas (3) supplied to the nozzles (2) is controlled by the exhaust gas of the Stelzer engine. 10. A method according to any one of claims 1-8, characterized in that the working air compressed in the compressor is sucked into the compression chamber (26, Figs. 2 and 4) via the suction opening (4, released by the cow) (7, 13). ) d & koiven is near its outer position.