EP2473405A2

EP2473405A2 - Gyroplane

Info

Publication number: EP2473405A2
Application number: EP10768376A
Authority: EP
Inventors: Otmar Birkner
Original assignee: Otmar Birkner
Current assignee: AutoGyro AG
Priority date: 2009-09-04
Filing date: 2010-09-02
Publication date: 2012-07-11
Also published as: DE102009040278A1; WO2011026478A3; DE102009040278B4; CN102574582B; BR112012004964A2; BR112012004964A8; US20120181378A1; WO2011026478A2; RU2012112949A; US8690100B2; CN102574582A

Abstract

The invention relates to a gyroplane comprising a motor (18), a rotor head (14) and a torque transmission device for transmitting torque of a motor (18) to the rotor head (14). According to the invention, the torque transmitting device comprises a pneumatic coupling (28).

Description

gyrocopter

The invention relates to a gyroplane with a motor, an engine head and a torque transmission device for transmitting a torque of the motor to the rotor head.

As with all aircraft, the goal of helicopters is to construct them as easily as possible. This applies especially to gyroplanes, because they must not exceed a maximum mass of 450 kg in order to be approved as an air sports equipment. Thus, there is a desire to construct the torque transmission device particularly lightweight. However, in the case of existing helicopters, this is limited by the fact that the torque transmission device has to be designed in such a way that it can handle torque peaks. Such torque peaks may arise at the beginning of pre-rotation, for example, when the pilot accelerates too early.

From US Pat. No. 5,544,844 a gyroplane is known which has a hydraulically actuated coupling. In this hydraulically actuated clutch oil pressure is built up via a lever, which is passed to the clutch and there causes the switching operation. Also with this gyrocopter there is the problem that the pilot can engage too fast, so that the torque transmitting device is overloaded behind the clutch. To avoid that

CONFIRMATION COPY As described above, the torque transmitting device must be oversized.

From US 6,062, 508 a compound aircraft is known, which has a main rotor for takeoff and landing and wings for cruising. To switch the engine from the main rotor to a propeller, a multi-plate clutch is provided. In such a combined aircraft must be transferred to the main rotor so much power that a sufficiently large buoyancy can be generated so that the aircraft can start. This requires a powerful engine and powerful torque transfer device. The requirements of the aircraft from the document are therefore not comparable to the requirements of a gyrocopter. In particular, in the combined aircraft is not the problem of a torque transmitting device, which must be designed oversized, since when starting so large power must be transmitted that power peaks can be intercepted during coupling without further action.

From US Pat. No. 7,448,571 B1, a gyrocopter is known, in which the angle at which the rotor blades of the main rotor are oriented is changed automatically. On the exact design of the coupling is not discussed in the document.

From US 2,712,911 a combined aircraft is known, which can be operated both as fixed-wing aircraft and as rotorcraft and has a magnetic coupling. It has been found that such magnetic couplings are unsuitable for use in gyroplanes, since the required for generating the necessary currents alternator means a large additional weight.

DE 10 2007 004 168 A1 and DE 0 2007 032 488 A1 disclose pneumatic clutches for land vehicles. The invention has for its object to provide a gyroscope, in which an overload of the torque transmission device is avoided during pre-rotation and at the same time has a low weight.

The invention solves the problem by a generic gyroscope in which the torque transmitting device comprises a pneumatic clutch.

An advantage of the inventive solution is that the coupling can be designed so that when engaging a maximum torque is not exceeded. For this reason, the drive train can be designed so that it safely transmits this predetermined maximum torque, but not significantly larger torques. However, since the torque transmission device need not be designed for any pilot misoperation, it can be designed to be lighter in weight.

It is a further advantage that damage in the drive train can be avoided by operating errors. This increases the reliability and availability of the gyrocopter.

It is another advantage that the coupling behavior of the gyrocopter is independent of environmental conditions. In known clutches comprising a belt drive, the static friction coefficient and the sliding friction coefficient decrease with increasing humidity. In particular, when the belt drive has become wet, it can therefore easily come to slip. Because some considerable power has to be transmitted via the coupling, the belt will easily wear too much when slipping. In contrast, the pneumatic clutch can be designed as a dry friction clutch, which is essentially maintenance-free.

It is a further advantage that the coupling can be arranged so that a drive part and an output part of the coupling are coaxial with each other and ner crankshaft of the engine run. During pre-rotation, it can come so by the applied torque to no major displacement of the engine relative to the hull of the gyrocopter. For this reason, a motor mount for the engine can be made less stiff, which saves additional weight.

Known from the prior art are electrical couplings that switch via a magnetic field. However, electric clutches have been found to be less suitable for gyroplanes, among other things, because during pre-rotation over a long period considerable torques of about 35 Newton meters must be transmitted. This leads to thermal expansion of the friction lining and requires an increased travel, which in turn makes a large electric current necessary to close the clutch. Although an electric clutch so advantageous because of the simple control, the peculiarities of the gyroscope lead to serious disadvantages that make an application unattractive.

In the context of the present description, the engine is in particular a cylinder engine.

The rotor head is understood in particular to be that unit of the gyroscope which articulates the rotor with the rigid hull. In other words, the rotor head is that component to which the rotor is fastened and by means of which the rotor can be pivoted relative to the hull.

The torque transmission device is understood in particular to mean an entirety of those components which are arranged in a torque flow behind the engine and in front of the rotor head. If the rotor head has a ring gear which is driven by a pinion, the torque transmission device ends with the pinion.

According to a preferred embodiment, the coupling is a dry friction clutch. Such dry friction clutches have two friction partners, which can be brought into and out of engagement with each other by being delivered to each other. There is no liquid between the two friction partners, so that adhesion-slip effects exist only to a small extent. Preferably, the friction partners are protected by a housing from the ingress of moisture.

It is favorable if at least one of the two friction partners is grooved, in particular radially grooved, so that frictional heat can be dissipated particularly well.

In a preferred embodiment, the pneumatic clutch comprises a drive shaft, an output shaft and a pneumatic cylinder, wherein the pneumatic cylinder radially surrounds the output shaft and / or the drive shaft. Here, the pneumatic cylinder is understood to mean the entire component of cylinder and piston. By contrast, the cylinder is understood to mean the cylindrical cavity in which the piston runs. An advantage of this structure is that it is particularly space-saving.

Preferably, the pneumatic cylinder has an annular cross-section. In this way, the pneumatic coupling is particularly short and compact and manages with a small number of components. The cylinder can also be referred to as an axially hollow-drilled cylinder.

Preferably, the pneumatic clutch has an engagement bearing having a first bearing ring, which is rotationally fixedly connected to the pneumatic cylinder, and a second bearing ring, which is rotatably arranged relative to the pneumatic cylinder comprises. In this case, the first bearing ring is preferably connected to the piston of the pneumatic cylinder. An engagement bearing is a rolling bearing configured to transmit axial forces. The engagement bearing preferably transmits the full axial load generated by the pneumatic cylinder. Preferably, the gyroplane comprises a drive train, wherein the drive shaft is part of the drive train, and a power take-off, wherein the output shaft is part of the drive train. The clutch preferably has a release spring which is arranged for transmitting the load torque in the torque flow between the drive train and the drive train. A release spring is understood in particular to mean a spring which allows axial movement of at least one part of the drive train to at least part of the drive train. The release spring thus allows the load torque to be transferred from the engine to the rotor head and at the same time to move two parts of the drive train respectively relative to each other. In this way, a frictional engagement between two components of the clutch can be produced.

Particularly preferably, the release spring biases the pneumatic cylinder in its rest position. The rest position is preferably the position of the pneumatic cylinder in which it has its minimum extension or deflection. In this position is a piston of the pneumatic cylinder, which runs in the cylinder, usually on the front side, ie on the cylinder head. For safety reasons, it is generally provided that the clutch does not transmit any torque in this position. If the compressed air supply fails during the flight, it can not happen that the rotor is braked.

Preferably, the pneumatic clutch comprises a friction lining and an anchor plate, wherein the release spring is formed so that the friction lining and the anchor plate, when the pneumatic cylinder is pressure-free, have a rest distance of at least 0.5 mm. This leads to a particularly high level of operational reliability, because it is ensured that any thermal expansion of the components of the clutch, for example, by engine heat or sunlight, does not cause the clutch closes unintentionally. Preferably, the pneumatic cylinder has a stroke of at least 2 mm. This makes it possible to provide a friction lining having a thickness of at least 2 mm. At the beginning of pre-rotation, a relatively high torque of, for example, 35 Newton meters must be transmitted with an optionally high power of, for example, 80 kW. This leads, in particular with slipping clutch at the beginning of the rotation, to a high thermal load on the friction lining and thus to high wear. Due to the large stroke, which is made possible by the use of a pneumatic cylinder, the pneumatic coupling has a long service life.

Preferably, the pneumatic cylinder is arranged to act directly. This is to be understood in particular that the piston of the pneumatic cylinder is arranged so that a movement of the piston by a predetermined stroke leads to a change in a distance between the friction lining and armature plate by exactly this stroke. This saves the use of levers and leads to a particularly robust and at the same time lightweight pneumatic coupling.

In particular, inexperienced pilots, it may happen that is engaged too quickly. This leads to torque peaks in the drive train between the engine and rotor head, which lead to damage if the drive train is not designed sufficiently stable. In order to safely absorb the torque peaks, a heavy drive train is necessary with conventional gyroplanes. According to a preferred embodiment, the pneumatic clutch comprises a compressed air supply line to the pneumatic cylinder, which comprises a throttle. Preferably, the compressed air supply line comprises a throttle inlet valve, in particular a non-return throttle inlet valve.

The throttle, the throttle inlet valve and the non-return throttle inlet valve are designed such that a sudden application of the nominal pressure to the compressed air supply leads to a coupling-in period from the time the nominal pressure is applied to the transmission of the complete torque. from powertrain to power train is at least 100 milliseconds. The coupling-in period is preferably at most 5 seconds. For coupling, it is then sufficient to open an inlet valve, in particular the throttle inlet valve. During the Einkoppelzeitspanne the transmitted torque increases preferably monotonically, in particular strictly monotonous, so that the rotor comes to speed. Through controlled engagement, torque peaks are avoided, so that all components of the drive or output line can be designed lightweight.

Preferably, the gyrocopter on a mounting device for mounting the clutch, wherein the pneumatic cylinder is rotationally rigidly connected to the mounting device. This has the advantage that the compressed air can be supplied via a line that does not have to rotate.

Preferably, the clutch has a slip torque that is less than a maximum transmissible torque of arranged in the torque flow behind the clutch components. If, for example due to a pilot error, too much torque is applied by the engine to the drive side, the pneumatic clutch starts to slip before a torque is reached, which could lead to damage of the components of the power train. This increases the reliability and robustness of the gyrocopter.

Preferably, the clutch is arranged coaxially with a crankshaft of the engine. This has the advantage that acting during pre-rotation torques lead only to a small extent to the fact that the engine shifts relative to the hull. That is, engine mounts do not warp relative to the hull and can therefore be made softer and therefore lighter in weight.

Preferably, the gyrocopter has a in the torque flow between the drive shaft and output shaft arranged Ausgleichsvorrich- tion, which has in the axial direction of a compensator rigidity, in particular a tensile rigidity and / or torsional stiffness, which has at most one fifth of the rigidity of the other components of the torque transmission device. In particular, the compensation device is arranged and designed so that a thermal heating of the drive shaft and / or the output shaft, for example at 90 ° C, causes an axial force on the drive shaft, which is smaller than a predetermined maximum force, which may be for example 100 N.

According to a preferred embodiment of the gyrocopter has a arranged in the torque flow between the drive shaft and output shaft balancing device comprising a rubber-elastic compensation element. This compensating element is arranged so that it deforms in a thermal expansion of the compensating device of the drive shaft and / or the output shaft, so that an axial force is limited to one or more bearings of the drive shaft.

The compensation element preferably has a torsional stiffness which is smaller than the torsional stiffnesses of the other components of the torque transmission device. For example, the torsional stiffness is at most one fifth of the torsional rigidity of the component with the next lower torsional rigidity. As a result, the time-varying torque of the engine, which is usually a cylinder engine, smoothed, which protects the rotor head. It is possible that the compensating element additionally or alternatively has a tensile rigidity, as described above.

Preferably, the torque transmission device comprises an angle gear, which is arranged in the torque flow behind the clutch.

Preferably, the torque transmission device comprises a shaft joint, which is arranged in the torque flow behind the angle gear so that a displacement of the motor due to the torque output of the engine is compensable relative to the fuselage. By this is meant that an elastic deformation of the receptacle which carries the motor or parts of the fuselage to which the motor is fastened, relative to the other components of the torque transmission device is compensated by the universal joint. It is thereby possible to make the components by means of which the motor is fastened to the hull less rigid, which makes them lighter in weight. When the motor exerts a torque on the torque-transmitting device during pre-rotation, the hull thus warps relative to the torque-transmitting device only as far as the universal joint.

The universal joint may be configured to compensate for a time varying angle between the two shafts connected by the universal joint. Alternatively or additionally, the shaft joint is designed to compensate for a movement of the waves in or against its longitudinal axis.

Particularly preferably, the universal joint is arranged at the height of the propeller axis of rotation. This is to be understood that the shaft joint has at most a small distance, in particular of less than 40 cm, from the propeller axis of rotation.

In the following the invention will be explained in more detail with reference to an exemplary embodiment. It shows

1 shows a gyro according to the invention in a view from the

Page,

Figure 2 shows a component of the gyroscope according to Figure 1 with the

The torque transfer device,

3 shows a pneumatic coupling of the torque transmission device in an exploded perspective view from the side,

Figure 4 shows the pneumatic coupling in a sectional exploded view from the side

FIG. 5 is a sectional exploded view from below,

FIG. 6 is a sectional view of the pneumatic coupling;

Figure 7 is an exploded perspective view of a second embodiment of a pneumatic clutch for a gyro according to the invention and

8 shows the coupling of Figure 7 in a sectional exploded view.

FIG. 1 shows a gyroplane 10 according to the invention which has a rotor 12 which is fastened to a rotor head 14. The rotor head 14 is driven by a not shown in Figure 1 engine, which is also provided for driving a propeller 16.

FIG. 2 shows the engine 18 in the form of a cylinder engine, which has two 20.1, 20.2 is attached to a support structure 22 of a hull 23. The engine 18 has a crankshaft 24 which is connected to a drive shaft 26 of a pneumatic clutch 28. An output shaft 30 of the pneumatic clutch 28 is connected to an angle gear 32. The angle gear 32 has an output shaft 34 which is connected via a shaft joint 36 with a mast shaft 38.

The angle between the output shaft 34 and the output shaft 30 is between 80 ° and 100 °. In the present case, the angle is 90 °. The Mastwelie 38 terminates in a pinion 40 which cooperates with a ring gear 42 of the rotor head 14.

The propeller 16 has a propeller axis of rotation D and the shaft joint 36 extends at the height of the propeller axis of rotation D. It is also possible to arrange the shaft joint D below the propeller axis of rotation D or just above.

Figure 3 shows an exploded perspective view of the coupling 28. The pneumatic coupling 28 comprises a mounting device 44 for mounting on the hull 23 (Figure 2). The mounting device 44 comprises four connecting elements 46.1, 46.2, 46.3, 46.4, which are mounted on a base plate 48 and connected to a front plate 50. Radially within the connecting elements 46, a driver 52 is arranged, which is in the installed position with the crankshaft 24 (Figure 2) in engagement. The driver 52 includes an anchor plate 54, which is a friction partner of a friction joint, wherein the other friction partner is formed by a friction lining 56. The friction lining 56 is mounted on a friction lining support plate 58.

When the motor 18 (FIG. 2) is operating, the driver 52 rotates and thus also the armature plate 54 rotates. Via a ball bearing 59, (see FIG. 5), an axis centering 60 is mounted on the driver 52, in which the output shaft 30 engages and so stored. On the front plate 50, a cylinder housing 62 (Figure 5) is attached to a cylinder 64. In the cylinder 64, a piston 66 (Figure 3) which is toroidal and has a circular disk-shaped cross-section runs. The cylinder housing 62 and the piston 66 are parts of a pneumatic cylinder 68.

On the piston 66, an engagement bearing 70 is mounted, which comprises a first bearing ring 72 (Figure 5) and a second bearing ring 74. The first bearing ring 72 is rotationally rigidly connected to the piston 66, whereas the second bearing ring 74 is rotationally fixed to the Reibbelagistagplatte 58 is mounted.

At the Achszentrierung 60 a release spring 76 is attached, the arms 78.1, 78.2, 78.3 (Figure 3). At the ends of the arms 78, the release spring 76 is attached to the Reibbelagistagplatte 58, for example screwed. In FIG. 3, the holes for the screw connections for the arms 78. 2 and 78. 3 can be seen in the friction lining support plate 58.

In the uncoupled state, the motor rotates the driver 52 and thus the armature plate 54. All other components of the clutch 28 do not rotate. The piston 66 rests with an end face 80 (FIG. 3), which has a circumferential, circular groove, in the cylinder 64 in FIG.

If the pressure in the cylinder 64 is increased, the piston 66 moves from this rest position against the force of the release spring 76 in FIG. 5 by a stroke H to the right. As a result, the engagement bearing 70 and the friction lining support plate 58 also move toward the anchor plate 54 until frictional engagement between the friction lining 56 and the anchor plate 54 occurs.

Due to the frictional engagement, the friction lining support plate 58 rotates together with the second bearing ring 74 of the engagement bearing 60. The piston 66, however, does not rotate. Since the arms 78.1, 78.2, 78.3 are fastened to the friction lining support plate 58, the axis centering 60 and thus also the output shaft 30, which is rotationally rigidly connected to the axis centering 60, rotate. The pressure in the cylinder increases 64, the release spring 64 pushes the piston 66 back into its rest position and the friction lining 56 comes out of engagement with the anchor plate 54th

FIGS. 3, 4 and 5 could give the impression that the connecting elements 46 are in contact with one of the rotating elements, however, they are only connected to the end plate 50 and, for example, the friction bearing support bar 58 and the armature plate 54 rotate freely radially inside the Connecting elements 46.

The friction lining 54 has a multiplicity of grooves 82.1, 82.2,. The utility 82 extend radially outward and enforce the friction lining 54 completely. Thus, the friction lining 54 is cooled during engagement by an air flow, which is caused by the centrifugal force. The anchor plate 54 is perforated, which improves the cooling of the anchor plate 54.

The pneumatic cylinder 68 is connected by means of a schematically drawn throttle inlet valve 84 and a compressed air connection 86 with a not shown compressed air supply, for example, 8 bar. The throttle inlet valve 84 is operable via an electrical or mechanical actuator from a cockpit of the gyroscope.

FIG. 7 shows an exploded perspective view of a pneumatic clutch for a gyroplane according to the invention. It can be seen that the clutch 28 has a compensation device 88, which is arranged in the present case in the torque flow behind the engine and in front of the armature plate 54. The balancer 88 is configured to receive axial forces resulting from thermal expansion of the drive shaft. This avoids that bearings of the drive shaft are charged excessively.

In the embodiment according to FIG. 7, the compensation device 88 comprises a compensation element 90 made of a rubber-elastic material, for example made of rubber. In principle, any suitable shape for the compensation element is possible, but it is particularly favorable when the compensation element 90 as in the present case projections 92.1, 92.1, ..., with the first coupling projections 94.1, 94.2, ... a first coupling element 98 on the one hand and second coupling projections 96.1, 96.4 of a second coupling element 100 cooperate. The coupling elements 98, 100 and the compensation element 90 are formed so that in each case a projection 92 of the compensation element 90 between a first projection 94 and a second projection 96 is arranged. The torque flow extends from a respective first projection 94 through a tooth 92 of the compensation element 90 in a second projection 96. This causes an attenuation of the fluctuating due to the ignitions of the cylinder engine torque.

Furthermore, the compensation element 90 is arranged between a first coupling element 98, on which the first projections 94 are formed, and the second coupling element 100, on which the second projections 96 are formed, such that an axial force acting in the axial direction R acts , the compensating element 90 compresses, so that the axial force acting on an unspecified bearing of the drive shaft, even with a thermal expansion of the drive shaft is limited to a value below a maximum permissible axial force.

FIG. 8 shows the coupling according to FIG. 7 in a sectional exploded view.

REFERENCES 0 gyrocopter

60 axis centering

2 rotor

62 cylinder housing

4 rotor head

64 cylinders

6 propellers

66 pistons

8 engine

68 pneumatic cylinders0 intake

70 engagement bearing

2 supporting structure

72 first bearing ring

3 hull

74 second bearing ring4 crankshaft

76 release spring

6 drive shaft

78 arm

8 clutch

80 front side

0 output shaft

82 groove

2 angle gear

84 Throttle inlet valve4 Output shaft

86 Compressed air connection6 Universal joint

88 Compensating device 8 Mast shaft

90 Ausgleichselement0 pinion 92 projection

2 gear ring 94 first coupling projection 4 mounting device 96 second coupling projection 6 connecting elements 98 first coupling element 8 base plate

100 second coupling element0 end plate

2 driver D propeller axis 4 anchor plate H stroke

6 friction lining R axial direction

8 friction lining support plate

9 ball bearings

Claims

Claims:

1. gyrocopter with

(a) a motor (18),

(b) a rotor head (14) and

(c) a torque transmission device for transmitting a torque of the motor (18) to the rotor head (14),

characterized in that

(D) the torque transmitting device comprises a pneumatic clutch (28).

2. gyrocopter according to claim 1, characterized in that the pneumatic coupling (28)

a drive shaft (26),

an output shaft (30) and

a pneumatic cylinder (68) radially surrounding the output shaft (30) and / or the drive shaft (26).

3. gyrocopter according to one of the preceding claims, characterized in that the pneumatic cylinder (68) has a circular-annular cross-section.

4. gyrocopter according to one of the preceding claims, characterized in that the pneumatic clutch (28) has an engagement bearing (70), the

a first bearing ring (72) which is torsionally rigidly connected to the pneumatic cylinder (68), and

a second bearing ring (74) rotatably mounted relative to the pneumatic cylinder (68).

5. gyrocopter according to one of claims 2 to 4, characterized by a drive train, which comprises the drive shaft (26), and a power take-off, which comprises the output shaft (30),

wherein the clutch (28) comprises a release spring (76) arranged to transfer the load torque in the torque flow between the drive train and the drive train.

6. gyrocopter according to claim 5, characterized in that the disengagement spring (76) biases the pneumatic cylinder (68) in its rest position.

7. gyrocopter according to one of claims 5 or 6, characterized in that the pneumatic coupling (28)

a friction lining (56) and

an anchor plate (54),

wherein the release spring (76) is formed so that the friction pad (56) and the anchor plate (54), when the pneumatic cylinder (68) is pressure-free, have a rest distance of at least 0.5 millimeters.

8. gyrocopter according to one of the preceding claims, characterized in that the pneumatic cylinder (68) has a stroke (H) of at least

2 millimeters.

9. gyrocopter according to one of the preceding claims, characterized in that the pneumatic cylinder (68) is arranged to act directly.

10. gyrocopter according to one of the preceding claims, characterized by a compressed air supply line to the pneumatic cylinder (68), which comprises a throttle (84).

11. gyrocopter according to one of the preceding claims, characterized by

a mounting device (44) for mounting the clutch (28), wherein the pneumatic cylinder (68) is rotationally rigidly connected to the mounting device (44).

12. gyrocopter according to one of the preceding claims, characterized in that the coupling (28) has a slip-torque, which is smaller than a maximum transmittable torque of torque in the flow behind the clutch (28) arranged components.

13. gyrocopter according to one of the preceding claims, characterized in that the coupling (28) coaxial with a crankshaft (24) of the motor (18) is arranged.

14. Gyrocopter according to one of the preceding claims, characterized by a torque flow between the drive shaft (26) and the output shaft (28) arranged compensating device (88) in the axial direction (R) a compensator stiffness, in particular a tensile rigidity and / or torsional stiffness, which has at most one fifth of the rigidity of the other components of the torque transmission device.

15. Gyrocopter according to one of the preceding claims, characterized by a torque flow between the drive shaft (26) and the output shaft (28) arranged compensating device (88) comprising a rubber-elastic compensation element (90).

16. gyrocopter according to the preamble of one of the preceding claims, characterized in that the torque transmission device comprises an angle gear (32).

17. The gyrocopter according to claim 16, characterized in that the torque transmitting device comprises a shaft joint (36) which is arranged in the torque flow behind the angle gear (32) so that one of the torque output of the motor (18) conditional displacement of the motor (18) is compensable relative to the fuselage.

18. gyroplane according to claim 17, characterized by

a propeller drivable by the engine (18) and having a propeller axis of rotation (D),

wherein the shaft joint (36) is arranged at the height of the propeller axis of rotation (D).