DE2505551A1 - ARRANGEMENT FOR HAILING UP A HELICOPTER - Google Patents

Description

ΡαΟΓΕΞISiTANV / ÄUTE A. GRÜNECKER

DlPl INQ.

W. STOCKMAIR

DR.-INQ. AeE (CALTECH)

K. SCHUMANN

. DR. RER. NAT. · DIP.L.-PHYS.

P. H. JAKOB

DIPL.-ΙΝΘ.

G. BEZOLD

DR. RER. NAT, DIPL.-CHEM.

MUNICH

E. K. WEIL

DR. RER. OEC. INQ. "

LINDAU

MUNICH 22

MAXIMIUANSTRASSE 43

1θ February 1975 P 8794-

Dominion Aluminum Fabricating Ltd.

Hawkestone Road,

Mississauga, Ontario L5C278, Canada

Arrangement for hauling in a helicopter

The invention relates generally to a retrieval arrangement a helicopter, and more particularly relates to a helicopter landing system.

Arrangements for retrieving a helicopter, which from a Winches with a constant tension. Make use of, for example described in the following US patents:

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U.S. Patent 3,303,807, Stewart et al .; U.S. Patent 3,526,2688, üaekken ;, U.S. Patent 3,552,689 (BaekkenJ, U.S. Patent 3b5992? (Baekken,), and U.S. Patent 3,640,490 to Baekken, J.

In such arrangements, the helicopter is on the flight deck of a ship tied up by a cable that transmits a constant pull, by means of a operated by a servo control winch. This stabilization move is maintained during the critical landing period when there is a risk of the distance accidentally changes between the ship and the helicopter due to the wind or sea. By such a measure the necessary safety is guaranteed to get the helicopter to an exact landing point on the To guide flight deck.

These arrangements typically use a servo-controlled hydraulic motor geared to the winch drum connected is. Furthermore, cable receiving devices and hydraulic shock absorbers are required to avoid extreme shock loads on the cable. Such cable receiving devices and shock absorbers have long been considered necessary in such arrangements as for example, in US Pat. No. 2,444,154 (Hing) is described.

As soon as the helicopter has landed, it is essential to secure the helicopter immediately on the flight deck, with regard to this purpose the above patents (Baekken) describe sophisticated telescopic arrangements which are attached to the underside of the helicopter and corresponding catching devices the Ji ¹ lugdeck, urn appropriate

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Detect probes when the helicopter is on deck lands.

While known helicopters are in the have proven to be essential to the safe and accurate landing of helicopters on the Jj'lugdeck of a Ship, regardless of EoIl and Pounding movements due to the movement of the sea, so suffer they nevertheless suffer from the disadvantage that they are very complex and expensive. In addition, due to the complicated structure These arrangements adversely affects the reliability, so that frequent maintenance and large storage for Spare parts are required.

The object of the invention is to provide an arrangement for retrieving to create a helicopter of the type mentioned above, which is particularly economical and at the same time has an extremely high level of reliability.

To achieve this object, the invention provides an arrangement before, which is characterized in that an eddy current coupling is provided through which an electric drive motor is coupled to the winch drum. The electric motor drives the input element of the eddy current clutch at a constant speed. A stationary field coil in the coupling generates a magnetic field, which is alternating Murder and south poles generated on the output element. A relative movement or a slip between the input and the output element generates eddy currents in the input element the clutch. An interaction between these eddy currents in the input element and the induced magnetic poles the output element supplies the. electromotive force which

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transmits a torque from the electric motor to the winch drum. A control of the output speed and thus the tension on the cable is controlled by a controller ensures that the excitation of the field winding of the clutch feeds and modulates. The winch drum has so far a special configuration that the drum diameter decreases in a spiral immediately before touchdown, to increase the holding voltage in the cable »

According to deil invention is thus a recovery system for a Helicopter on board a ship or for other applications created in which a winch with constant Tension ties a helicopter to the flight deck of a ship to control the landing of the helicopter and the Secure helicopter. The arrangement has an eddy current clutch, which acts as a controllable torque transmitter acts, through which excessive shock loads on the retrieval cable are avoided. The recovery cable will rolled up on a winch drum during landing to maintain stabilizing tension. the Winch drum is designed in a special way in such a way that the drum diameter immediately before being placed in a spiral to increase the tension in the cable and to secure the helicopter on the flight deck to facilitate.

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The invention is described below, for example, with reference to FIG Drawing described; in this show:

1 shows a pictorial and a schematic representation of the system according to the invention for retrieving a helicopter,

Fig. 2 is a simplified block diagram showing the structure and how the eddy current clutch works in the: System illustrates

3 shows a section through part of the eddy current coupling, which illustrates their structure in detail,

Fig. 4- a graphical representation of typical slip-torque curves, which the operation of the formed from the motor, the eddy current clutch and the winch Illustrate combination,

Fig. 5 is a simplified pictorial representation of the invention High voltage safety winch and

6 shows a block diagram of an alternative embodiment. of the control system according to the invention for retrieval.

In the drawing and in particular in FIG. 1, a helicopter 11 is shown which has a retrieval cable 12, which on one. Load hook or a similar device as 13 is attached to the underside of the helicopter 11. The fastening sequence in which the retrieval cable 12 attached to the load hook 13 does not form part of the invention. However, the process can either be done by hand or

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automatically-done. For example, a line cable and a corresponding connection from the helicopter 11 can be lowered onto the flight deck, and the hauling cable

12 can be attached to the conduit cable either manually or automatically. The lead wire would then go to the Helicopter 11 hauled up, the hauling cable 12 being brought along in order to attach it to the load hook 13. the actual attachment of the retrieval cable 12 to the load hook

13 can be done in any number of known ways. For example, a short piece a retrieval cable carried in flight must be permanently attached to the load hook 13 with one end, while the other end is releasably attached to the helicopter fuselage in such a way that it is accessible to the crew. When the main haul-in cable 12 is brought up through the cable and a corresponding connection to the helicopter, the crew of the Helicopter, attach the short length of the haul-in cable carried in flight to the main haul-in cable by hand, which was brought up by the conduit.

In an alternative embodiment, instead of the load hook 13, a cable winch arrangement in the helicopter could be used 11 be arranged. This arrangement would be equipped with an energy source, which is connected to a winch, to which a line cable or a cable ring is connected in such a way that one end of this cable from the helicopter could be lowered to the flight deck of a ship. The end of the line cord that was lowered in this way is attached to an.dem Einholkabel 12, either by hand or by an automatic device, and then pulled back into the helicopter, bringing the hauling cable with him. The line cable winch assembly also has one Device - which serves to automatically grasp the retrieval cable and uncouple the retrieval cable from the line cable.

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The automatic connection system for establishing a connection between the conduit cable and the retrieval cable may have an intermediate piece or an adapter which is attached to the .End of the retrieval cable to engage the end of the line cable and the guide device to enable which on the flight deck of a ship is provided to hold the end of the retrieval cable in a stationary position while the moving end of the lead wire is brought into engagement with it.

Obviously there are many other ways in which the connection between the helicopter 11 and the hauling cable 12 can be produced.

The retrieval cable 12 runs through an inlet trumpet 14 in the flight deck of the ship (not shown). Then the retrieval cable 12 guided around a guide roller 15, and from there to a winch drum 16. The winch drum is driven by an AC induction motor 17 at constant speed Speed over a (water- or air-cooled) Eddy current clutch 18 driven. A brake 19 »which is either an electromagnetic brake or a friction brake can be carried out, can be connected to the winch drum 16 and directly during the backup operation after the helicopter has touched down on the flight deck.

Fig. 2 shows in general form in a block diagram the combination of the AC motor 17 , the eddy current clutch 18 and the winch drum 16. As the name suggests, the clutch operates on the eddy current principle to generate a torque from the AC motor

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to be transferred to the winch drum 16. The clutch points three main components: a drive shaft with an inductor drum 21, an output shaft with a rotor 22 and a stationary field coil assembly 23. Each of the rotatable Elements 21 and 22 of the eddy current coupling can rotate independently of the other element. When the field coil 2J with a DC voltage of a corresponding Control device is fed, so go the magnetic lines of force from the field winding through the rotor 22 in the Inductor drum 21 and back through the inductor drum of field coil 23 · This is illustrated by the dashed arrows showing the magnetic lines of force in the Specify cross section according to FIG. 3.

By a relative movement between the inductor drum 21 and the clutch rotor 22, eddy currents are generated on the inner surface of the inductor drum; These eddy currents • generate an electromotive force which transmits a torque from the inductor drum 21 to the clutch rotor 22. A difference in speeds between the drum 21 and the rotor 22 which is referred to as slip is, must be present between the inductor drum and the rotor so that a torque is transmitted to the winch drum 16 can be. The transmitted torque is proportional to the excitation of the field coil 23 »which of a corresponding control device is controlled. When the field coil excitation is increased, the field strength increases and less slip is required in order to transmit a corresponding torque to the winch drum 16. If, on the other hand, the field excitation is lower, the field strength decreases and a larger slip is required to

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a corresponding torque on the winch drum 16

transferred to. '

The Ji'ig. 4- is a graph showing a ii 'represents a family of typical slip-torque chambers, where the t3b transmission torque is a JJhinction of the Slip between the inductor drum 21 and the clutch rotor 22 is shown. Each curve represents a special value of an excitation of the field coil 23. From this graphical representation can be seen * that the curves between the two vertical dashed lines lie, run relatively flat, which is a constant Represents torque over a wide range of slip. the thick line between the slip-torque curves for the field excitations of 8.5 and 11 amperes is a section of a slip torque curve, which represents a relatively constant tension of about 1360 kp in the retrieval cable according to a particular embodiment which has been manufactured and tested.

From Fig. 4- it can be seen that the distance between the two vertical dashed lines divided in the middle by a line, the left half with "rolling up" and the right half is labeled "Unroll". These · Center line represents the optimal slip revolutions per Minute for a desired tension in the retrieval cable. Changes in hatching., According to either side in with respect to this center line or the optimal value result from incorrect changes in the distance between the helicopter and the flight deck, whatever the wind or the Lake. Furthermore, the cable tension is not

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to be understood as a limitation, d. i.e., the helicopter pilot can exceed this tension and go into a climb at any time without this Cable to loosen. Thus, the eddy current clutch creates a wide area when rolling up and unrolling the Winch drum ensures while the hauling cable is kept under a constant tension, so that thereby excessive shock loads on the retrieval cable are avoided.

According to Fig. 1, the deck officer has a control console, which is shown generally at 25. In a typical embodiment, this control console can be a hot start control 26 for starting the AC induction motor 17. In addition, the control console 25 is provided with a pivot lever 27, which is mechanically connected to the tap of a potentiometer 28. The potentiometer 28 is connected to a power source, which supplies a constant reference voltage V, and the movement of the tap through the lever 27 supplies a control voltage for the control unit 31.

The control unit J1 provides DC excitation for the Field coil of the eddy current coupling 18. In general, the control unit 31 can have a servo amplifier and a motor 32 ' which have differential inputs. One of the inputs to the servo amplifier is with the movable tap of the potentiometer 28 connected. The other of the inputs to the servo amplifier is connected to a voltage sensor 33, which sits on the shaft of the guide roller 15. Consequently sets the control voltage at the tap of potentiometer 28

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<3-the desired voltage in the haul-in cable 12, and the voltage output signal of the tension sensor 23 represents the actual tension in the haul-in cable 12. The output of the servo amplifier and the motor 32 is mechanically connected to ^: the tap of a potentiometer 34- which is on a source of coupling field DC excitation 35 is connected. This feedback control system enables the tension in the haul-in cable 12 to be precisely controlled by the deck officer and maintained via the control unit, while the use of a motor 17 of lower power is also possible. . .

One of the inputs of the servo amplifier and the motor 32 can be connected to a speed sensor 4-0, which is fed through the output shaft of the clutch motor 22 is driven, instead of to the cable tension sensor 33 according to i "ig. 6. Since the speed of the clutch motor of the tension in the recovery cable .12 is directly proportional, this would System also offer the possibility that the tension in the retrieval cable can be precisely controlled.

As soon as the hauling cable 12 is fastened to the load hook 13 during operation, the deck officer gradually sets the cable under tension by having. lever 17 on the control panel 25 moved accordingly. To maintain altitude, the pilot increases of the helicopter 11 the total angle of attack. The resulting increase in thrust and the centering force, which by the cable 12 is applied, combine in such a way that the helicopter over the landing area on the flight deck is stabilized. The pilot's natural flight corrections are complete with this stabilizing effect

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compatible. A constant tension in the recovery cable 12 is automatically maintained, namely during the hover flight and the descent flight, without being influenced by the helicopter or the movement of the ship, by the above-mentioned servo amplifier and motor systems and by a Bolle, which at one end of a lower J ¹ e of the tension-standing lever is attached, which is pivotally attached to the ship in such a way that the retrieval cable is passed over the pulley after it has been passed through the trumpet inlet 14. During the retrieval process, the spring force causes. which acts on the lever so that the roller deflects the cable on its way from the trumpet inlet 14 to the winch 16. As soon as the helicopter has landed, an increase in the tension in the recovery cable causes the lever to rotate about its pivot point. The spring attachment points between the lever and the ship are designed so that when the cable is tightened between the trumpet inlet and the winch, the spring force passes through the pivot point of the lever, thereby preventing the lever system from exerting any force on the cable exercise.

Fig. 5 shows the unique one in greater detail Configuration of the winch drum 16. Immediately after placement of the helicopter on the flight deck, the helicopter must be secured. The winch drum 16 is with killen equipped, which formed on ihper outer peripheral surface are helical around the uniform "winding of the retrieval cable along the axis of the drum. The diameter of the drum is over most of the axial length the drum constant. At the end of the operation of the cable drum, immediately before contact between the helicopter wheel and · the deck comes about, the drum diameter decreases in such a way that the last .groove 38 in the drum surface becomes a waning spiral. This is shown in the figure

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the radius dimensions R. of the main part of the drum and Hp of the decreasing radius of the groove 358 is shown. this leads to to an increase in the holding voltage which is inversely proportional to the diameter of the drum. ;

The trumpet enema 14- according to I ¹ Ig. 1 can be rigidly mounted in the deck of the ship or it can be mounted in a housing which is able to move laterally over the ship's deck. A slot would be cut through the deck to allow the cable to pass through for all sections of the trumpet opening and case. The trumpet opening and housing "would be held between their end positions by braking means until the helicopter landed, whereupon the brake would be released to allow the trumpet inlet and housing to run into a position which the resulting The brake is applied again as soon as the trumpet inlet has reached the housing, while the cable tension is increased at the same time to secure the helicopter on the l'lugdeck _.:

The advantages of the arrangement according to the invention are significant. The eddy current clutch and its auxiliaries cost only about 40 % of the amount that the hydraulic motor and its auxiliaries as they are currently used cost. Much improved reliability results from the reduction in the number of parts of the helicopter retrieval system, the elimination of all hydraulic parts, and the reliability inherent in the eddy current clutch. The installation and commissioning of the system according to the invention for hauling in a helicopter are greatly simplified, since adjustment, cleaning of hydraulic lines, leak detection

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_ 14- -

and similar actions normally required in the facility currently in use fully omitted.

It should be noted that the embodiment shown serves only as an example and that within the scope of the invention, various modifications in structure and arrangement can be provided.

- Patent claims 509833/0722

Claims (4)

250555T claims 1. arrangement for hauling in a helicopter, with a --- 'jEinho! Cable, which can be detached during the landing process. can be attached to a helicopter, with a winch drum, which is used to wind up the hauling cable, and with a device, which is used to apply a controllable torque to the winch drum, characterized in that an electric motor rotating at constant speed ( 17) it is provided that an eddy current coupling continues. (.18) is present, which has an inductor drum (.21), which can be driven by the electric motor (, 17J rotating at constant speed, which furthermore has an independently rotatable Hotor. (22), which is arranged in such a way that it drives the winch drum (, 16.), and which has a field coil (.23) in order to magnetically couple the inductor drum (.21) and the rotor (.22) to one another, this coupling the excitation current in the coil (, 23 ) is directly proportional, and that a device is provided which serves to control the excitation current in the field coil (23). 2. Arrangement according to claim 1, characterized in that the a manually operated control device for controlling the excitation current in the field coil (23) (27) further comprises a device in order to select the desired tension in the retrieval cable (12) for sensing the tension in the cable (12) and finally a feedback device which on. the control device and the scanning device respond, 509833/07 2 2 around the excitation current in the field coil (23) automatically to control. 3- arrangement according to claim 1, characterized in that the winch drum (16) in that part of the drum (16) has a decreasing diameter (Rp), which is assigned to that phase of rolling up the retrieval cable which is immediately followed by the landing of the helicopter precedes, whereby the tension in the hauling cable (12) is inversely proportional to the diameter of the winch drum (16) increases. 4. Arrangement according to claim 1, characterized in that the device for controlling the excitation current in the i'eldspule (23) is a manually operated control device (28) to reduce the tension in the retrieval cable (.12) to select, furthermore has a device (40) which, for sensing the rotational speed of the winch drum (16) serves, and furthermore has a return device which acts on the control device (28) and on the scanning device (40) responds to automatically control the excitation current in the J field coil (23). 50 9833/0722 Blank page