WO2023093996A1

WO2023093996A1 - Boom assembly and corresponding lifting assembly for helicopter rotor blades and corresponding mounting method

Info

Publication number: WO2023093996A1
Application number: PCT/EP2021/083184
Authority: WO
Inventors: Otto Kabilka
Original assignee: Otto Kabilka
Priority date: 2021-11-26
Filing date: 2021-11-26
Publication date: 2023-06-01

Abstract

The invention relates to a boom assembly and a corresponding lifting assembly for helicopters (1), and a corresponding mounting method. The boom assembly is provided with: a base unit (8) having a first upper side and a first underside, wherein the first underside can be rotationally fixed to a rotor head (2) of the helicopter (1) and wherein the first upper side has a rotary guiding unit (11); a guiding unit (9) having a second upper side and a second underside, wherein a bearing unit (9a) is provided on the second underside, into which the rotary guiding unit (11) can be introduced in such a way that the guiding unit (9) is rotatably mounted in the rotary guiding unit (11), and wherein a receiving unit (9b) is provided on the second upper side; and a telescopic boom unit (10) having a first element (10a) which can be laterally moveably received in the receiving unit (9b), and having a second element (10b) which can be laterally removeably introduced into the first element (10a).

Description

BOOM ASSEMBLY AND RELEVANT HELICOPTER ROTOR BLADE LIFTING ARRANGEMENT AND RELEVANT ASSEMBLY METHOD

The present invention relates to a boom assembly and a corresponding lifting assembly for helicopters and a corresponding assembly method.

DE 197 16 525 C1 discloses a device for removing rotor blades, in particular a helicopter main rotor. It is equipped with a blade connection acting between the rotor blade and rotor head, a holder that can be mounted separately from the blade connection and detachably on the rotor head, and a support arm that is pivotably mounted on the holder in the direction of removal of the rotor blade and holds the rotor blade in a stable position while relieving the blade connection.

The main drive element of a helicopter is the main rotor. The tail rotor is only used to balance torque and change direction. The rotor head with the rotor blades is attached to the upper end of the main rotor mast. The rotor head and the number of attached rotor blades differ depending on the helicopter (2 to 5 and more rotor blades).

The rotor mast and rotor head of a helicopter are designed to be so stable that they absorb any loads (vertical forces and bending moments) during flight. These two helicopter components can therefore also be subjected to corresponding forces and bending moments on the ground.

The removal and installation of helicopter components above a certain dead weight is usually carried out with cranes in maintenance hangars. Components are, for example, rotor blades, recovery winches, turbines, gears. The dead weight of these helicopter components is between approx. 50 kg and approx. 120 kg.

To do this, the fitter stands on the platform on the helicopter, for example next to the main rotor gearbox, or on a maintenance platform next to the helicopter. In detail, these are, for example, the following components: - rotor blades

- mountain winds

- Helicopter drive (turbine, gearbox)

- transport loads

Helicopter rotor blades have to be removed and installed regularly for regular inspection of the rotor blades and the rotor mast and for transport in airplanes and on trucks. Recovery winches (also on both sides of the helicopter) are attached to the outside of the helicopter above the cabin doors and are often only installed for planned operations and then removed again (e.g. in the German Armed Forces). Drive units, such as turbines or gears, are only removed and installed outside of assembly halls in emergencies (e.g. when used in the field by the German Armed Forces).

The mounting positions of the rotor blades on the helicopter are up to 4.5 m above the ground. The rotor blades are very sensitive goods and must be treated very carefully during installation and removal. The installation and removal of the components is first a lifting task (height over approx. 3.5 m) and in the assembly position an adjustment and assembly task in order to attach the connecting means (bolts) with a high degree of accuracy. As long as a crane or a forklift is available, the dismantling and assembly process is not a problem.

If these lifting aids are not available, both dismantling and assembly problems have to be overcome and occupational safety problems arise (e.g. overhead work on stepladders). In any case, 2 - 3 employees are required for this.

The transport of helicopters in transport aircraft to a site is of particular importance. This transport takes place with dismantled rotor blades. At the place of use, it is of great importance to be able to assemble the rotor blades as quickly as possible without using large tools. The object of the invention is to be able to carry out assembly work and disassembly work involving lifting or other lifting work on the helicopter without major additional tools.

The present invention provides a boom assembly and a corresponding lifting assembly for helicopters according to independent claims 1 and 11, respectively, and a corresponding assembly method according to independent claim 15.

Preferred developments are the subject matter of the respective dependent claims.

The idea on which the present invention is based consists in attaching a boom arrangement to the rotor head of the helicopter and using this to upgrade the helicopter to a lifting device or a crane in just a few simple steps.

The invention provides a boom assembly and helicopter hoist that allows both tasks (lifting and leveling) to be performed with little human effort and minimal safety risk. Especially with rotor blades (e.g. 2 - 5 rotor blades), the working time can also be significantly reduced. Occupational safety is thereby increased in a considerable way. Theoretically, the entire dismantling and assembly can be completed by a specialist fitter or loading (possibly with just one assistant) in a short time.

According to a further preferred development, the rotary guide device is designed as a circular pipe bend which has a plurality of inner struts. This ensures high stability of the rotary guide device. The space required next to the helicopter for assembly and disassembly is very small.

According to a further preferred embodiment, support blocks are attached to the inner struts, via which the first underside can be placed on corresponding rotor head flanges. In this way, a rotor head-specific interface can be created. According to a further preferred embodiment, the support blocks have attachment extensions for a respective tensioning strap, via which the respective support block can be attached to the associated rotor head flange in a rotationally fixed manner. This enables a quick and stable type of attachment.

According to a further preferred embodiment, the inner struts each have at least one screw hole, the inner struts being able to be screwed to a rotor head plate via respective support blocks. If necessary, existing screw inserts can be used to assemble the basic device.

According to a further preferred embodiment, the guide device has a carrier profile, at the opposite ends of which a respective U-shaped bearing of the bearing device is attached, so that the guide device can be pushed laterally onto the rotary guide device. This enables the guide device to be easily mounted on the rotary guide device.

According to a further preferred embodiment, a locking pin is provided in the center of the rotary guide device, with a corresponding receiving hole being provided in the center of the carrier profile, as a result of which the guide device can be centered with respect to the rotary guide device. This ensures stable alignment.

According to a further preferred embodiment, the guide device has a roller device on the second upper side, which is attached to the carrier profile, wherein the first element of the telescopic boom device can be inserted into the roller device and can be locked therein by pivoting struts attached to the carrier profile, in order to form the receiving device . In this way, the guide device can be easily stored in a laterally displaceable manner.

According to a further preferred embodiment, the second element of the telescopic boom device can be locked in an end position when it is pulled out of the first element. According to a further preferred embodiment, the second element of the telescopic boom device has a plug-in eyelet in its outer end region. This enables a simple way of attaching further components, such as an elevator device.

Embodiments of the invention are shown in the drawings and explained in more detail in the following description.

Show it:

1 is a perspective view of a helicopter boom assembly according to a first embodiment of the present invention;

FIG. 2 shows a perspective detail view of the base device from FIG. 1 ;

FIG. 3 shows a perspective detail view of the guide device from FIG. 1 ;

FIG. 4 shows a perspective detail view of the cantilever device from FIG. 1 ;

Figures 5a)-c) are perspective views of successive stages of assembly in attaching the boom assembly for helicopters according to a first embodiment to the rotor head;

Fig. 6 shows a helicopter hoist assembly according to a second embodiment of the present invention;

7a), b) perspective representations to illustrate a use of the lifting arrangement when disassembling/assembling a rotor blade; and

8 shows a perspective detail view of a base device in a third embodiment of the present invention. In the figures, the same reference symbols denote the same or functionally identical components.

1 is a perspective view of a helicopter boom assembly according to a first embodiment of the present invention.

In Fig. 1, reference numeral 1 designates a helicopter having a four-bladed rotor, for example. The rotor has a rotor head 2 to which four rotor blades 3 are flanged in pairs opposite each other.

The cantilever assembly according to the first embodiment bears the general reference numeral 4 and is attached to the rotor head 2 in a maintenance or assembly/disassembly state.

The boom arrangement 4 has a modular structure and has the following main components that can be assembled together, the total weight of which can be measured at 10 to 15 kg, so that the boom arrangement 4 can easily be carried along as an item of equipment in the helicopter 1 .

The first component is a base device 8 with a first upper side and a first lower side, the first lower side being non-rotatably attachable to the rotor head 2 of the helicopter 1 and the first upper side having a rotary guide device 11 provided with inner struts 111 . It is attached, for example, by means of tension belts 14 to rotor head flanges or bearing mounts 20, as will be explained in more detail later.

The second component is a guide device 9 with a second upper side and a second lower side, with a bearing device 9a being provided on the second lower side, into which the rotary guide device 11 can be introduced in such a way that the guide device 9 is rotatably mounted in the rotary guide device 11, and wherein a receiving device 9b is provided on the second upper side. The third component is a telescopic boom device 10, which has a first element 10a, which can be received in the receiving device 9b in a laterally displaceable manner, and which has a second element 10b, which can be inserted into the first element 10a in a laterally extendable manner. To insert the telescopic boom device 10 into the receiving device 9b, it is only necessary to loosen and tighten screw nuts 60, as will be explained in more detail later. A plug-in eyelet 100 is provided at the end of the second element 10b, which makes it possible to attach further components, for example an elevator device.

FIG. 2 shows a detailed perspective view of the base device from FIG. 1 .

As shown in Fig. 2, the rotary guide device 1 1 is designed as a circular pipe bend, which has a plurality of inner struts 1 1 1. In the illustrated example of the four-bladed rotor, these are four inner struts 1 1 1 , each extending in opposite directions from a center, corresponding to the course of the four rotor blades 3.

Four support blocks 13 are attached, e.g. screwed, to the inner struts 111, via which the first underside of the base device 8 can be placed on the corresponding four rotor head flanges or bearing mounts 20. For this purpose, the support blocks have circular segment-like recesses on their underside, which are adapted to the contour of the rotor head flanges or bearing mounts 20 .

The four support blocks 13 have attachment projections 113 for a respective tensioning belt 14, via which the respective support block 13 can be attached to the associated rotor head flange 20 in a rotationally fixed manner. Lashing is done, for example, by means of a respective turnbuckle 14.

In the center of the rotary guide device 11, a locking pin 12 is provided on the upper side (cf. FIG. 5a)), which engages and disengages via a locking lever device 120. is cash. This serves to align the guide device 9, as will be explained in more detail below.

The base device 8 can be adapted to the different constructions of the rotor head 2 as desired. The further components described below can be designed in the same way independently of the rotor head 2 .

Fig. 3 shows a perspective detail view of the guide device from Fig. 1.

The guide device 9 has a carrier profile 90, at the opposite ends of which a respective U-shaped bearing 95a, 95b of the bearing device 9a is attached, so that the guide device 9 can be pushed laterally onto the rotary guide device 11.

A corresponding receiving hole 96 is provided in the center of the carrier profile 90 for receiving the locking pin 12, as a result of which the guide device 9 can be centered with respect to the rotary guide device 11.

The guide device 9 has a roller device 16 on the second upper side, which is attached to the carrier profile 90 via rigid vertical struts 99c, 99d. In the present example, two pairs of opposing rollers 16 are provided.

The first element 10a of the telescopic jib device 10 can be inserted into the roller device 16 and can be locked therein via the screw nuts 60 by pivoting struts 99a, 99b attached to the carrier profile 90, in order to form the receiving device 9b.

To reduce the sliding friction, four sliding pads 160 are provided on the insides of the vertical struts 99c, 99d and the pivoting struts 99a, 99b, which are formed, for example, from a plastic with a low friction factor. FIG. 4 shows a perspective detail view of the cantilever device from FIG. 1 .

The telescopic boom device 10 is made up of two square profiles. It has a first square element 10a, which can be accommodated in a laterally displaceable manner in the receiving device 9b, and has a second square element 10b, which can be inserted into the first square element 10a in a laterally extendable manner.

In its extended end position, the second square element 10b can be locked, e.g. by a push-button mechanism (not shown). The second square element 10b of the telescopic boom device 10 has in its outer end area a plug-in eyelet 100 into which, for example, a retaining clip device 30 can be inserted, as explained later.

In use, the first square element 10a is preferably first fully extended and locked before the telescopic boom device 10 is attached to the guide device 9 . The second square element 10b is pulled out depending on the desired position, e.g.

5a)-c) show perspective views of successive assembly stages in the attachment of the boom assembly for helicopters according to a first embodiment to the rotor head.

With reference to FIG. 5 a ), the base device 8 is first placed on the rotor head 2 from above, so that the support blocks 13 are seated flush on the rotor head flanges or bearing mounts 20 . This is followed by lashing down using the tensioning straps 14. The locking pin 12 is locked in place using the locking lever device 120.

Subsequently, with reference to FIG. pins 12 is mounted by means of the locking lever device 120. Thus, the guide device 9 is stably rotatably mounted on the rotary guide device 11.

Then the nuts 60 of the pivoting struts 99a, 99b are loosened and the pivoting struts 99a, 99b folded down laterally so that the first element 10a of the telescopic boom device 10 can be inserted into the roller device 16 after the first and second element 10a, 10b have been preassembled.

Finally, with reference to Fig. 5c), the first element 10a of the telescopic boom device 10 is inserted into the roller device 16 and the swivel struts 99a, 99b are folded up and locked by means of the screw nuts 60, so as to receive the first element 10a in the receiving device 9b so that it can be displaced laterally , as shown in Fig. 1.

6 shows a helicopter hoist assembly according to a second embodiment of the present invention.

The lifting arrangement according to the second embodiment has a boom arrangement as explained in connection with FIG. 1 . On the first element (10a) of the boom device 10 there is a helicopter-specific marking 200 for indicating a predetermined working position when the second element 10b is fully extended. This working position can be a receiving position for a rotor blade, for example.

A retaining bracket device 30 is attached to the second element 10b (cf. Fig. 4), in particular inserted into the plug-in eyelet 100, with a winding device 6, e.g. a remote-controllable electric drive, being suspended from the retaining bracket device 30 in such a way that it extends laterally over the second element 10b survives. The elevator device 6 has an upper hook 6a, by means of which it is suspended in the holding bracket device 30. The retaining bracket device 30 is also expediently attached to the guide device 9 before the cantilever device 10 is attached. The elevator device 6 has a cable pull 7 at one end and a fastening eyelet 6b is provided at the other end. A gripping tool 5 for gripping a rotor blade 3 can be attached to it, for example. During operation, the position of the elevator device 6 changes due to the extension and retraction of the cable 7.

The elevator device 5 typically weighs about 10 kg, which is why it makes sense to extend the cable pull in the ground position before the cantilever device 10 is attached. Then only the hook 6a needs to be hung in the holding bracket device 30 . Depending on the task, the fastening eyelet 6b is required on the ground or above the rotor blade 3.

In this way, a crane device for a helicopter 1 is created in the same way.

7a), b) show perspective views to illustrate use of the lifting arrangement when disassembling/assembling a rotor blade.

First, a lifting arrangement according to FIG. 6 is attached to the rotor head 2 of the helicopter 1 and a gripping tool 5 for gripping a rotor blade 3 is attached to the elevator device 6 .

The rotor blade 3 is assembled or disassembled in a corresponding assembly or disassembly position, with the gripping tool 5 being moved to the corresponding assembly or disassembly position by means of the cable pull 7 .

The second element 10b of the cantilever device 10 is locked here, and lateral displacements of the rotor blade 3 are brought about by a displacement of the first element 10a of the cantilever device 10 . Rotor displacements are brought about by rotating the guide device 9 in the rotary guide device 11 . When changing from one rotor blade 3 to another rotor blade 3, the rotor head 2 is first rotated and then the guide device 9 is rotated so that the lateral working position next to the helicopter 1 can be maintained.

This ensures that the space required next to the helicopter is minimal.

FIG. 8 shows a perspective detail view of a base device in a third embodiment of the present invention.

In this embodiment, the base device 8 is screwed to the rotor head 2 . The inner struts 111a each have at least one screw hole 105 for this purpose. The inner struts 111a are screwed to a rotor head plate 15 via respective support blocks 13a.

The screw holes in the rotor head plate 15 are used, for example, to attach a cover (not shown) during normal operation.

Although the present invention has been explained above on the basis of preferred embodiments, it is not limited thereto but can be modified in many different ways.

In particular, the geometric design of the individual components is only exemplary and can be varied in many ways.

Although the lifting arrangement has been explained in relation to the assembly or disassembly of rotor blades, it is in principle suitable for any lifting work.

Claims

patent claims

A boom assembly for helicopters (1) comprising: a base means (8) having a first top and a first bottom; wherein the first underside is rotatably attachable to a rotor head (2) of the helicopter (1) and wherein the first top has a rotary guide device (11); a guide device (9) having a second upper side and a second lower side; a bearing device (9a) is provided on the second underside, into which the rotary guide device (11) can be introduced in such a way that the guide device (9) is rotatably mounted in the rotary guide device (11), and wherein a receiving device (9b ) is provided; and a telescopic boom device (10) which has a first element (10a) which can be received in the receiving device (9b) in a laterally displaceable manner and which has a second element (10b) which can be inserted in a laterally extendable manner in the first element (10a). is.

2. Boom arrangement according to claim 1, wherein the rotary guide device (11) is designed as a circular pipe bend which has a plurality of inner struts (111).

3. Boom arrangement according to claim 2, wherein the inner struts (111) support blocks (13) are attached, via which the first underside on corresponding rotor head flanges (20) can be placed.

4. Boom arrangement according to claim 3, wherein the support blocks (13) have suspension extensions (113) for a respective tension belt (14) via which the respective support block (13) is non-rotatably attachable to the associated rotor head flange (20).

5. Boom arrangement according to claim 2, wherein the inner struts (1 1 1 a) each have at least one screw hole (105) and the inner struts (1 1 1 a) can be screwed to a rotor head plate (15) via respective support blocks (13a).

6. Boom arrangement according to one of the preceding claims, wherein the guide device (9) has a carrier profile (90), at the opposite ends of which a respective U-shaped bearing (95a, 95b) of the bearing device (9a) is attached, so that the guide device ( 9) can be pushed laterally onto the rotary guide device (11).

7. Boom arrangement according to claim 6, wherein a locking pin (12) is provided in the center of the rotary guide device (11) and a corresponding receiving hole (96) is provided in the center of the carrier profile (90), whereby the guide device (9) for the rotary guide device ( 1 1 ) can be centered.

8. Boom arrangement according to claim 6 or 7, wherein the guide device (9) has a roller device (16) on the second upper side, which is attached to the carrier profile (90), the first element (10a) of the telescopic boom device (10) being in the Roller device (16) can be inserted and can be locked therein by pivoting struts (99a, 99b) attached to the carrier profile (90), in order to form the receiving device (9b).

9. Boom arrangement according to one of the preceding claims, wherein the second element (10b) of the telescopic boom device (10) can be locked in an extended end position from the first element (10a).

10. Boom arrangement according to one of the preceding claims, in which the second element (10b) of the telescopic boom device (10) has a plug-in eyelet (100) in its outer end region.

11 . Helicopter lift assembly (1) comprising: a boom assembly according to any one of claims 1 to 10; and an elevator device (6) attached to the second member (10b) of the telescopic boom device (10).

12. Lifting arrangement according to claim 11, wherein a retaining bracket device (30) is attached to the second element (10b), in particular is plugged into the plug-in eyelet (100), and wherein the elevator device (6) is suspended from the retaining bracket device (30) in such a way that that it protrudes laterally over the second element (10b).

13. Lifting arrangement according to claim 11 or 12, wherein the elevator device (6) comprises a cable (7).

14. Lifting arrangement according to claim 13, wherein a gripping tool (5) for gripping a rotor blade (3) is provided, which can be attached to the cable (7).

15. Assembly method for assembling or disassembling a rotor blade (3) of a helicopter (1) with the steps:

Attaching a boom assembly according to any one of claims 1 to 10 on the rotor head (2) of the helicopter (1);

attaching an elevator device (6) to the second element (10b) of the telescopic boom device (10) which has a cable (7);

Attaching a gripping tool (5) for gripping a rotor blade (3) to the elevator device (6);

Attaching the gripping tool (5) essentially in the center of gravity of the rotor blade (3);

15 Assembling or disassembling a rotor blade (3), the gripping tool (5) being moved to a corresponding assembly or disassembly position by means of the cable pull (7).

16. Assembly method according to claim 15, wherein the second element (10b) of the cantilever device (10) is locked and lateral displacements of the rotor blade (3) are accomplished by displacing the first element (10a) of the cantilever device (10).

17. Assembly method according to claim 15 or 16, wherein rotary displacements by rotating the guide device (9) in the rotary guide device (11) are accomplished.

16