DE102012013527A1 - Rope drum for e.g. inner-board winch such as rescue hoist, of helicopter, has coupling link rotationally coupling cable guide drive to drum cylinder or to drum drive, where cable guide drive axially displaces direction-reversible guide unit - Google Patents

Abstract

The drum (1) has a drum cylinder (2) for rolling-up a rope (3), and an electronic controllable, electrical drum drive (4) for rotation of the drum cylinder. A cable guide (5) comprises a guide unit (6) axially directed for supplying the rope on the drum cylinder. A cable guide drive (7) i.e. spindle drive, axially displaces the direction-reversible guide unit. A spindle (17) i.e. screw rod, has a spindle pitch, which is constant in a central region and decreases in spindle ends (13, 15). A coupling link (8) rotationally couples the cable guide drive to the drum cylinder or to the drum drive. The drum drive is designed as a brushless direct-current (DC) motor with an angular position sensor (14) and as a torque motor or as a component of a motor and a gear box.

Description

The invention relates to a cable drum for a capstan winch, in particular for a rescue winch of land or aircraft. The pulling force of winches is determined by the drive torque and the lever arm as the radius of the outermost rope layer on the cable drum. The tensile force therefore decreases with the number of cable layers. For many applications, however, a constant tensile force is required regardless of the layer. Especially winches for passenger transport depend on a constant or controllable traction.

In order to make the tensile force on the cable drum comparable, capstan winches have long been known. Spinning winches have a rope spool, around which the rope is first looped and only then wound up on a cable drum. The tensile force of the rope spool depends on the attached load.

By means of the cable drum, the rope is biased to the spill head, to ensure the necessary frictional torque at this.

The traction can be evened out in mechanical winds by the engine speed of the drive is changed. In hydraulic winches control valves can be provided for this purpose. Such a hydraulic winch is for example off DE 26 16 470 A1 known. Construction and integration of the winch in a hydraulic circuit are relatively expensive. To control the rate of descent may need to be provided a positive displacement pump and a throttle valve with adjustable throttle performance.

Furthermore, these winches are often equipped with a slip clutch, which is exposed to wear and can cause noise during operation. If rope length measurement is required, additional components must be provided. In particular, if the determination of the actual unwound cable length is mandatory, the determination must be ensured even in case of unforeseen events, a referencing should be possible or the rope length determination for security reasons should be redundant, complex design measures are required.

Object of the present invention is therefore to avoid the disadvantages mentioned above and to improve a cable drum for a capstan, which is intended in particular as rescue helmets for helicopters.

The object is achieved by a cable drum for a capstan winch comprising a drum cylinder for rolling up a rope, an electronically controllable electric drum drive independent of the capstan drive for rotating the drum cylinder, a cable guide with a guide means for axially directing the cable onto the drum cylinder, a cable guide drive for axial displacement of the direction-reversing guide means, a spindle which forms the Seilführungsantrieb with a shuttle as the sliding guide means, the spindle has a spindle pitch, which is constant in a central region and decreases at the spindle ends, and a coupling member for rotationally fixed coupling of the cable guide drive having the drum cylinder or to the drum drive.

Such a cable drum requires no mechanical coupling to a spill, so that the production and transport costs of the individual components is reduced and due to the almost no load on / unwinding is subject to only minor wear, thus significantly extending the service life of the capstan.

The drum drive is designed as an electric drive of the drum cylinder, wherein the drum cylinder can represent the rotor of the electric drive. The stator may be formed as part of a housing into which the cable drum can be inserted. It is preferably electronically adjustable.

An electronically controlled drum drive is preferably controlled so that it generates a constant cable pulling force during winding in all possible winding layers. On the spill of a capstan winch with a cable drum according to the invention, this ensures that the rope always has the friction required for the spill drive.

The drum cylinder is formed as a circular cylindrical hollow or solid body, which is preferably provided at its end faces with ribs to ensure a side guide for the rope to be wound in a plurality of radially superposed cable layers.

On the drum cylinder, the rope can be rolled up in several rope layers. As ropes can be rolled up, for example, made of polyethylene, for example, especially for heavy loads steel cables or plastic ropes.

For the orderly feeding of the rope, the cable drum has a cable guide with a guide means. The guide means ensures that the rope is not wound on the cable drum, but an arrangement in uniform cable layers, wherein in each rope layer, the windings abut each other or are constantly spaced from each other in tracks. The guide means is axially displaceable over a cable guide drive and over a coupling member connected to the drum drive via a fixed transmission ratio.

The cable guide drive is designed as a spindle drive with a spindle on which, for example, a spindle nut in the form of a shuttle is guided as the guide means. The spindle converts the rotational movement caused by the coupling member into a translatory axial movement. In the simplest construction, the spindle is designed as a threaded rod with a flat thread. For the purpose mentioned ball screws are suitable, which allow a high positioning accuracy and a low-friction running. A roller screw drive can also be provided. A designed as a crosshead spindle allows for the same direction of spindle rotation by a receding thread back and forth of the shuttle.

Due to the fact that the spindle drive is connected in a rotationally fixed manner to the drum drive, special measures are required in the area of the deflection of the shuttle in order to ensure uniform winding of the rope on the drum end side. For this purpose, it is provided to change the spindle pitch over the axial length of the spindle. While the lead pitch in a central area is constant, it is reduced at the turnaround points to ensure that during winding, the lower layer of rope is first completely closed and the next, overlying layer of rope does not begin offset. This will use the entire drum width. The axial feed is therefore limited at the end points so that the shuttle dwells for exactly two drum revolutions in the area of the end points. This halves the increase.

The coupling member connects the two drives such that they are coupled in a rotationally fixed manner. Under a rotationally fixed coupling is understood that the two rotors of the drives have a defined phase relationship to each other, so that when the phase position of a rotor, the angular position of the other rotor is known. Thus, each angular position of the cable guide drive is assigned an unambiguous one angular position of the drum cylinder, wherein the angular positions are to be considered going beyond 360 °. The number of revolutions of the drum cylinder are therefore in a fixed relationship to the number of revolutions of the rotor of the cable guide drive (1: 1, 1: n or m: n). With a 1: 1 ratio and meshing gears of equal size, they rotate synchronously, albeit with opposite directions of rotation. The rotor of the cable guide drive is designed as a threaded spindle and defines an axial position of a threaded spindle arranged on the spindle nut or a carriage.

The coupling means itself can mediate a translation, provided that this mediation is in phase. The rotational speeds of the drives are therefore always proportional to each other. Advantageously, angular position sensors can be arranged on the drum cylinder or on the drum drive so that the cable guide can be constructed solely from mechanical components. This simplifies the production and eliminates the need to connect cables to this module.

The cable drum ensures with the cable guide that under all circumstances a defined winding of the rope on the cable drum takes place. Since the number of turns per rope layer and the drum cylinder radius are known, the unrolled rope length is in a clear relationship to the phase position of the drum cylinder. The rope length determination can therefore be advantageously carried out within the cable drum. A detection on a possible spill drive is not required, so that the rope cap can be designed much easier.

The phase position of the drum cylinder can be determined easily. In a first embodiment, the cable length can be calculated by using a stepping motor and an arithmetic unit connected thereto. In a particularly simple embodiment of the cable drum can then be dispensed with additional sensors.

In another embodiment, the cable drum has one or more additional sensors for detecting the angular position, the speed, the Seilumlenkpunkte and / or the end points of the rope. They can be provided for adjustment, for determining reference positions, for reasons of redundancy, for determining the cable length or the unwinding speed. The sensors can be designed as angular position sensors, tachogenerators or position sensors for determining the cable end positions. In addition to or instead of electromagnetic transducers for angular position signaling, for example, incremental encoders can also capture part of the required quantities. If the cable drum is part of a capstan winch, these sensors can be dispensed with on the spill drive. This is particularly advantageous if the drum drive is designed such that it requires these sensors for its operation, so that the number of sensor elements in the capstan can be reduced overall.

Due to the proportionality of the rotational speeds of the drum drive and the cable guide drive they are in a fixed angular relationship to each other, so that the detection of the cable length not only on the cable guide drive, but also on the electric drum drive possible is. The cable guide drive can thus consist solely of mechanical components. A cable feed to Seilführungsantrieb can be omitted. By positioning the angular position sensor on the stator, bundling of the cables can take place, which simplifies the construction of the cable drum.

Particularly preferably, the angular position sensor is designed as a resolver. It can transmit the measured values inductively via the rotor position and thus work wear-free. The resolver supplies absolute values as measured values and therefore requires no adjustment with a reference point to be defined within a 360 ° revolution.

In a variant of the invention, the electric drum drive is designed as a brushless DC motor (BLDC motor). In this case, its sensors, which are used to determine the commutation, can be used in addition to detect the phase position of the drum cylinder and thus to determine the unwound cable length. It is particularly advantageous to operate the BLDC motor with a vector control in order to achieve a high positioning accuracy.

In principle, the cable drum according to the invention can be driven with various electric drives. A particularly strong, the slip and the game minimizing coupling of the two drives succeeds if they form a direct drive, so rotate at the same angular velocity.

For the cable drum torque motors are preferably provided. Torque motors have a high drive rigidity due to their high number of pole pairs, which is advantageous for the rotational phase strength according to the invention. They also build very compact, so they are well used in land or air vehicles in confined spaces. A winch with a cable drum driven by a torque motor is particularly suitable for rescue vehicles, where low maintenance and reliability are required. A good alternative to torque motors are motors with an additional gear, which forms with the motor upstream of the coupling member assembly.

In a development of the invention, the electric drive is arranged coaxially with the drum cylinder. In this case, the drive can be laterally flanged to the drum cylinder and thus also have a larger diameter than the drum cylinder, which may be necessary in particular for high power and allows easier cooling. Alternatively, the drum cylinder is formed as a hollow cylinder, in which the electric drive is partially or fully integrated.

The electric drive can also be arranged externally and transmit its torque to the cable drum via a gear arranged in the drum cylinder designed as a hollow cylinder, for example a planetary gear or a harmonic drive gear. For small strokes, a worm gear can be sufficient. The coupling member may also be formed as a planetary gear. Alternatively, the coupling member is a belt drive having, for example, a toothed belt or a chain. Another alternative is a gear assembly as a coupling member, which in contrast to the belt means is not lengthy and due to the always meshing teeth with little rotational play is afflicted.

One embodiment provides to secure the electric drive and thus the drum cylinder by means of an electrically opening, each loading holding brake. A wear-affected slip clutch is not provided, since its function is taken over by the integrated torque control of the above-mentioned drive system.

For the uniform winding of the rope, it is advantageous that the cable guide has sensors for detecting the running direction of the rope. If the rope reaches an edge of the drum cylinder, a reversal of the direction of the guide means can take place. The sensors may be part of the cable guide, for example by being arranged axially end on the cable guide drive. However, they can also detect the position of the cable guide as optical sensors without contact from outside.

Instead of sensors or in addition to these, the movement of the guide means can also be predetermined by mechanical force means such that an automatic reversal of direction takes place at the end points.

In a next embodiment, the cable guide is provided with a support roller for guiding the rope on the boat. The support roller makes the loads even and prevents infeed marks. Preferably, at least one support roller is arranged on each axial side of the shuttle.

In a further embodiment, the cable drum has an angular position sensor whose signal is used to calculate the length of the unwound cable by calculation. For this purpose, the angular position sensor is connected to an evaluation as an arithmetic unit, which either forms part of the cable drum or is arranged externally. Alternatively, the rope length is calculated directly from the control of the drum drive. Both embodiments allow a method, the rope length to be determined continuously. The rope length determination is reliably possible due to the non-rotatable coupling of the drives.

The cable drum may still be additionally equipped with a separate device for detecting the end of the rope to redundantly ensure that the rope is not completely unwound. The rope is usually connected at one end to the cable drum before it is wound up. During operation, the drum drive forces the cable in such a way that a constant prestressing is ensured, independent of unwound rope length.

To be able to confine the unwinding of the rope safely to the maximum allowable, for example, provided in the jacket of the cable drum at the point corresponding to the maximum allowable unwinding of the rope, for example, before the start of the fifth or third last turn of the unwound rope, a Attach sensor The sensor can detect a lifting of the rope at this point. For this purpose, for example, an inductive proximity switch is suitable. The proximity switch may itself be part of a braking device or act on further components on a braking device which mechanically prevents complete unwinding.

The cable drum can have limit switches to automatically prevent excessive handling. In addition, the cable drum can be provided with interfaces for signal transmission of the sensors to an external control electronics or for displaying the operating parameters.

The power electronics can be integrated directly into the cable drum so that the cable drum can be built as a compact, preassembled unit. It is particularly suitable for outboard helicopters due to its small size and good efficiency. Alternatively, it can also be provided at the installation site.

In summary, the invention provides a cable drum which causes a sufficiently large frictional force on a spill over the rope. The friction force on the spill is thus sufficiently high in both winding directions to safely lift or lower the attached load. The cable drum according to the invention is particularly suitable for capstan winches intended for mobile use.

The only picture shows a cable drum 1 a not shown spill winch for a helicopter. The rope drum 1 has a drum cylinder 2 for rolling up a rope 3 on, which is usually designed as a steel cable. From the rope 3 is only a part of the first rope layer shown. The one end of the rope is on the jacket of the drum cylinder 2 secured non-positively by a lock, not shown, in the form of a clamp.

The drum cylinder 2 has a cylindrical shell on the radial outer surface of the rope 3 wound up in layers. Axial, the shell is bounded by an annular disk-shaped and an annular drum cylinder wall, each having a limiting board 12 form. to allow the stacking of several radially superposed cable layers. So that the first layer of rope can be wound up over the entire drum width, the lock is on one of the shelves 12 or at least arranged close to them.

The drum cylinder 2 is a trained as a torque motor electric drum drive 4 driven. The drum drive 4 is partially within the drum cylinder designed as a hollow cylinder 2 arranged and protrudes on one side from the drum cylinder 2 out. The drum cylinder 2 is non-rotatable with the rotor of the drum drive 4 and is powered by an inverter from the 28 V DC or 115 V AC grid. The electric drum drive 4 is electronically regulated.

Due to the uniform winding, the rotational speed of the drum drive 4 not adjusted within the same rope layer to ensure a constant pull. When changing to the next rope layer, the constancy of the tension is adjusted by adjusting the torque of the drum cylinder 2 and thus by adjusting the speed of the drum drive 4 causes. At about ten rope days, a reduction of the speed from the innermost to the outermost layer of rope takes place by about half; at the same time the required torque increases to about twice.

Due to the constant tension it is ensured that in all operating conditions enough frictional torque between the rope 3 and the spill of the capstan, not shown, is available. The rope 3 therefore encloses the spill so tightly that the required friction is always high enough to increase the driving force of the spill on the rope 3 transferred to.

The rotation of the drum cylinder 2 is via a coupling element 8th on a cable guide drive 7 a rope guide 5 transfer. The cable guide drive 7 has a spindle 17 with a boat 16 as a guide 6 and an end-side gear, not shown, with the as a gear assembly 18 trained coupling member 8th the spindle 17 rotationally fixed with the drum cylinder 2 combines. The movement of the on the spindle 17 arranged guide means 6 thus takes place "synchronously" to the drum speed. To translates the gear assembly 18 through the drum drive 4 on the cable guide drive 7 applied rotational movement. It thereby provides an axial movement of the shuttle 16 sure, the thread pitch of the spindle 17 , and the drum diameter is adjusted. The translation is chosen so that the boat 16 always radially over the section of the drum cylinder 2 is positioned, that of the target track of the rope 3 equivalent. This results in a tight winding with a fixed number of wraps per rope layer.

The spindle 17 points in a middle area 11 over the drum width on a constant thread. Only at the spindle ends 13 and 15 takes the spindle pitch from such that the shuttle 16 for two turns of the drum cylinder 2 remains in the respective end position or the feed is at least reduced so much that even at the edge of the drum a complete filling of the rope layer is ensured. The winding pattern is thereby improved.

To further improve the rope feed are on the boat 16 two support rollers 19 . 21 arranged. The support rollers 19 . 21 lead the rope 3 , provide a uniform support and thus can prevent or at least reduce run-in traces.

To determine the rope length is designed as a resolver angular position encoder 14 , The angular position encoder 14 is on the drum drive 4 arranged and detects the rotational position of the rotor in a periodic range from 0 ° to 360 °, and also the number of turns made. The rope layer that is being unwound is through the spindle sensors 9 . 10 recorded and stored in an electronic unit, not shown. The length of the unrolled rope 3 can then be determined not only in a simple way and without the rope capstan. The length determination is particularly error-prone to unforeseen events, since the resolver detects the absolute position of the rotor and does not require referencing like incremental encoders. Furthermore, a continuous determination of the rope length can take place. The resolver is used simultaneously for pulse width modulation control.

The spindle sensors 9 and 10 are at the endpoints of the spindle 17 arranged and detect the switching of the direction of the shuttle 16 , Another sensor, which in the present case also acts as a switch, provides redundant calculation of the rope length as a means 20 for rope end detection sure that in any case a predetermined minimum number of wraps on the drum cylinder 2 remains.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 2616470 A1 [0004]

Claims (10)

Cable drum ( 1 ) for a capstan, comprising - a drum cylinder ( 2 ) for rolling up a rope ( 3 ), - an electronically controlled, electric drum drive ( 4 ) for rotating the drum cylinder ( 2 ), - a cable guide ( 5 ), which is a guiding means ( 6 ) for axially directed feeding of the rope ( 3 ) on the drum cylinder ( 2 ), - a cable guide drive ( 7 ) for the axial displacement of a direction reversible guide means ( 6 ), - a spindle ( 17 ), with a boat ( 16 ) as the sliding guide means ( 6 ) the cable guide drive ( 7 ), wherein the spindle ( 17 ) has a spindle pitch which in a central region ( 11 ) is constant and at the spindle ends ( 13 . 15 ), and - a coupling member ( 8th ), the cable guide drive ( 7 ) to the drum cylinder ( 2 ) or to the drum drive ( 4 ) rotationally fixed coupled. Cable drum according to claim 1, characterized in that the coupling member ( 8th ) as a gear group ( 18 ) or formed as a belt drive. Cable drum according to claim 1 or 2, characterized in that the cable drum ( 1 ) a sensor for detecting the direction reversal of the guide means ( 6 ) having. Cable drum according to one of the preceding claims, characterized in that the drum drive ( 4 ) as a brushless DC motor with an angular position sensor ( 14 ) is trained. Side drum according to one of the preceding claims, characterized in that the drum drive ( 2 ) is formed as a torque motor or as an assembly of a motor and a transmission. Side drum according to one of the preceding claims, characterized in that the drum drive ( 4 ) in the drum cylinder ( 2 ) is integrated. Cable drum according to one of the preceding claims, characterized in that the cable drum ( 1 ) Medium ( 20 ) for cable end detection. Cable drum according to one of the preceding claims, characterized in that the drum drive ( 4 ) is acted upon by a control electronics so that the cable pull force is constant over the changing winding thickness. Cable drum according to one of the preceding claims, characterized in that the cable drum ( 1 ) an angular position sensor ( 14 ) or a controllable drum drive ( 4 ) and for Seillängenermittlung from the phase signal of the angular position sensor ( 14 ) or is connected from the control with an evaluation. Use of a cable drum according to one of the preceding claims in an outboard winch or inboard winch of a helicopter.

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