EP4242162A1 - Method for controlling a winch assembly of a piste caterpillar, device for carrying out said method and piste caterpillar - Google Patents

Abstract

A method and device for controlling a winch arrangement (1) of a snow groomer (2), the winch arrangement having a winch cable and a winch arm (4) guiding the winch cable (3), which is rotatably mounted about a vehicle vertical axis (FH), is disclosed. The method has the following steps: - Detecting a change in a rope tension of the winch rope in a winch operation of the winch arrangement, - Specifying a setpoint range for an operational rope tension, - Specifying a limit value for the change in rope tension, - Comparing the detected change in rope tension of the winch rope with the specified limit value and - Controlling a rotary drive assigned to the winch arm, taking into account the comparison in such a way that if the limit value for the change in rope tension is undershot by an active compensating rotational movement of the winch arm, the operational rope tension is at least largely approximated to the specified setpoint range.

Description

FIELD OF APPLICATION AND STATE OF TECHNOLOGY

The invention relates to a method for controlling a winch arrangement of a snow groomer, wherein the winch arrangement has a winch cable and a winch arm guiding the winch cable, which is rotatably mounted about a vehicle vertical axis. The invention also relates to a device for carrying out such a method, comprising: a winch arrangement with a winding device for storing and winding the winch rope, which can be anchored to a stationary anchor point at a free end region facing away from the winding device; a drive device assigned to the winding device for introducing tensile forces onto the winch rope; a winch arm for feeding the winch rope to the winding device, the winch arm being rotatably mounted about a vehicle vertical axis, and a rotary drive assigned to the winch arm for generating active rotational movements of the winch arm about the vehicle vertical axis; and a control device for controlling the rotary drive of the winch arm, as well as a snow groomer with such a device.

A device described at the beginning is known from the applicant's product range and is used for snow groomers, which are sold by the applicant under the brand name "Pistenbully" in order to maintain and prepare steep ski slopes. The known device has a winch arrangement which is rotatably mounted about a vehicle vertical axis on a chassis of the snow groomer and has a winding device designed as a cable drum, which is assigned a drive device for a winch cable for introducing a tensile force onto the winch cable, the winch cable being placed on the cable drum can be wound up or unwound from the cable drum. A steel cable is used as the flexible winch cable in the known winch arrangement, with a locking device designed as a hook in the manner of a crane hook, which can be closed with a snap lock, being attached to a free end region of the steel cable facing away from the winding device. The winch arrangement is provided with a guide device, which is typically designed as a boom or as a winch arm with cable guide devices and which is intended for feeding the winch cable to the drive device. The winch arm enables the winch rope to be guided from the winding device over a driver's cab of the snow groomer, so that a driver of the snow groomer has the winch rope in his field of vision, at least in the main case of use when the snow groomer is oriented uphill. In addition, the winch arm can have the task of aligning the winch rope in the manner of a forced guidance in a predeterminable direction relative to the snow groomer in order to effect an advantageous attack of the tensile forces transmitted by the winch rope on the snow groomer. For this purpose, the winch arrangement has a rotary drive in order to position the winch arm laterally or to actively improve the steering behavior of the vehicle through a rotary movement.

To drive on and work on steep snowy terrain, the winch rope is pulled off the winding device and anchored or fixed at a stationary anchor point in an upper area of the terrain. The snow groomer then drives on the slopes with traction support from the tensioned winch cable, which is wound up and unwound via the winding device or its drive device depending on the position and travel of the snow groomer. The operation of the snow groomer with train support is also referred to below as winch operation. The winch operation enables, among other things, the snow groomer to prepare steep terrain that could not be navigated without this train support.

However, when the snow groomer is winching, it can happen that the winch cable is temporarily positioned on a terrain contour or on a surface of the ski slope, such as on a hilltop or a pile of snow, with a lateral offset from the direct alignment or path of the snow groomer uphill to the stationary anchor point fixed. This situation can occur, for example, if a different lane is selected when the snow groomer is traveling uphill than when it was traveling downhill. In this situation, the winch arm is deflected to the side or towards the temporary fixation point due to its floating, rotatable bearing. This results in enormous tension in the winch cable. If the friction force between the winch rope and the ground at the temporary fixation point becomes sufficiently low, for example because the snow groomer is moving uphill towards the anchor point or due to a transverse movement of the snow groomer, the winch rope suddenly snaps out of the temporary fixation, in a direct direction between the snow groomer and the stationary anchor point. This is often referred to as rope lay. When the winch rope snaps out or is released, extreme loads are created in the winch rope due to the high static pre-tensioning force of the winch rope. High dynamic mass forces arise, in particular longitudinal and transverse forces, which also act on the winch arrangement of the snow groomer through the winch cable and thereby shorten the service life of both the winch cable and the winch arrangement, in particular the winch arm. There is also the risk of negative force effects on the snow groomer itself, so that there can no longer be sufficient driving safety. Difficulties can also arise due to a sudden drop in winch rope tension the unstressed winch cable lies on the ground or the ski slope in front of the snow groomer and is driven over by the snow groomer.

One in the disclosure document DE 10 2007 061 110 A1 The method disclosed provides for arranging a mechanical and/or hydraulic compensator at a stationary anchor point for hanging the winch rope of the winch of a snow groomer, the compensator reducing the longitudinal vibrations and transverse vibrations occurring in the winch rope and the peak loads in the winch rope, ie between a winch machine and the anchor point and thus also intercepts the wind machine. In addition, a device is also disclosed which is a mechanical and/or hydraulic compensator which is designed in such a way that it absorbs and reduces the impact loads in excess of the normal load in piste operation due to freely swinging ropes. The compensator is arranged as a link between an anchoring device of the winch cable and the anchor point.

The patent specification EP 2 398 966 B1 discloses a snow groomer with a winch arrangement to facilitate handling of the snow groomer on steep slopes. The snow groomer includes a control unit and the winch assembly, which includes a rotatably mounted drum, a winch rope that is wound around the drum, an actuator assembly for rotating the drum, a first sensor for determining the position of the drum, a roller that is rotated by the winch rope and includes a second sensor for determining the position of the roller. The control unit is configured to sense the speed of the drum and the speed of the idler and to control the actuator assembly as a function of the speed of the drum, the speed of the idler, the position of the drum and the geometry of the idler and the drum Control the tension of the winch rope.

The disclosure document EP 1 118 580 A1 discloses a device for automatically adjusting and regulating the pulling force of the rope of a winch arrangement for a snow groomer. The device comprises a control and regulation unit which is connected to a controllable winch drive, an evaluation device which is connected to sensor elements and to the control and regulation unit. The sensor elements are pressure sensors which detect the pressure present at a shuttle valve with the highest value, which is connected between the delivery lines of right-hand and left-hand drives in a first direction of travel or in a direction of travel opposite to the latter, an algorithm being stored in the evaluation device , which calculates a setpoint based on the pressure value obtained by the pressure sensors, which controls the winch drive via the control unit. This setpoint is compared with an actual value measured using a force bolt attached to the traction cable and the control unit regulates the pulling force to the setpoint. The facility further comprises a rotary angle sensor which determines the angle of the winch rope or the winch arm with respect to the vehicle's longitudinal axis, with a signal proportional to the angle being formed which is fed to the evaluation unit for calculating the maximum permissible tensile force.

TASK AND SOLUTION

The object of the invention is to create a method, a device and a snow groomer of the type mentioned at the outset, which enable a high level of operational safety.

This task is solved for the method by the features of claim 1, for the device for carrying out the method by the features of claim 9 and for the snow groomer by the features of claim 13. Advantageous further developments and/or refinements of the invention are specified in the subclaims, the wording of which is hereby incorporated by reference into the description. This includes in particular all embodiments of the invention that result from the combinations of features that are defined by the references in the subclaims.

• Erfassen einer Änderung einer Seilspannung des Windenseils in einem Windenbetrieb der Windenanordnung,
• Vorgeben eines Sollwertbereichs für eine betriebsbedingte Seilspannung,
• Vorgeben eines Grenzwertes für die Seilspannungsänderung,
• Vergleich der erfassten Seilspannungsänderung des Windenseils mit dem vorgegebenen Grenzwert und
• Ansteuern eines dem Windenarm zugeordneten Drehantriebs unter Berücksichtigung des Vergleichs derart, dass bei einer Unterschreitung des Grenzwertes für die Seilspannungsänderung durch eine aktive Kompensationsdrehbewegung des Windenarms die betriebsbedingte Seilspannung dem vorgegebenen Sollwertbereich zumindest weitestgehend angenähert wird.

The method according to the invention for controlling a winch arrangement of a snow groomer has the steps:

• Detecting a change in rope tension of the winch rope in a winch operation of the winch arrangement,
• Specifying a setpoint range for an operational rope tension,
• Specifying a limit value for the change in rope tension,
• Comparison of the recorded change in rope tension of the winch rope with the specified limit value and
• Controlling a rotary drive assigned to the winch arm, taking into account the comparison in such a way that if the limit value for the change in rope tension is undershot by an active compensating rotational movement of the winch arm, the operational rope tension is at least largely approximated to the predetermined setpoint range.

Through the method according to the invention, a rope lay can be detected early on when the snow groomer is winching and the operational rope tension can at least largely be quickly restored or even approximately maintained by an active compensating rotational movement of the winch arm. In this way, the mechanical load on the winch rope as well as on the winch arrangement and the snow groomer can be kept low and operational safety can be increased.

When detecting the change in rope tension of the winch rope in the winch operation of the winch arrangement, the rotary drive assigned to the winch arm is initially passive or deactivated. With a passive rotary drive, the winch arm is positioned floating around the vehicle's vertical axis and can therefore be rotated freely. Detecting a change in rope tension of the winch rope requires a time-dependent detection of the rope tension of the winch rope using fundamentally known measuring methods. The change in rope tension of the winch rope serves as a controlled variable and can be defined, for example, by a change in the tensile force of the winch rope over a predetermined period of time. Such a value is preferably determined empirically.

The specified setpoint range for the operational rope tension defines a rope tension range in which the winch rope is tensioned or does not sag under the given operating conditions. The specified limit value for the change in rope tension indicates a value below which a rope lay or a sudden decrease in winch rope tension can be assumed.

The time-dependent change in rope tension of the winch rope is compared with the specified limit value for the change in rope tension. If the cable tension change falls below the limit value, the rotary drive assigned to the winch arm is activated or activated. The rotary drive causes a compensating rotational movement of the winch arm, so that an actual value of the operational rope tension is at least largely approximated or achieved to the specified setpoint range. For this purpose, the actual value of the operational rope tension is also recorded during the compensating rotational movement. The compensating rotational movement of the winch arm is carried out actively by the rotary drive of the winch arrangement or the winch arm and is therefore also referred to as active compensating rotational movement. On the other hand, a passive (floating) rotary movement of the winch arm occurs when the rotary drive is deactivated and the freely rotatable winch arm is rotated, for example by a tensile force applied to the winch arm. The winch arm can be rotatably mounted separately or rotatably arranged together with a support structure of the winch arrangement.

The method according to the invention for controlling a winch arrangement of a snow groomer is particularly advantageous for maintaining and preparing steep ski slopes using winches.

• Erfassen einer Änderung einer Drehstellung des Windenarms in dem Windenbetrieb der Windenanordnung,
• Vorgeben eines Grenzwertes für die Drehstellungsänderung,
• Vergleich der erfassten Drehstellungsänderung des Windenarms mit dem vorgegebenen Grenzwert und
• Ansteuern des dem Windenarm zugeordneten Drehantriebs unter zusätzlicher Berücksichtigung dieses Vergleichs derart, dass bei einer Überschreitung des Grenzwertes für die Drehstellungsänderung durch die aktive Kompensationsdrehbewegung des Windenarms die betriebsbedingte Seilspannung dem vorgegebenen Sollwertbereich zumindest weitestgehend angenähert wird.

In a further development of the invention, the method has the following further steps:

• Detecting a change in a rotational position of the winch arm in the winch operation of the winch arrangement,
• Specifying a limit value for the change in rotational position,
• Comparison of the detected change in rotational position of the winch arm with the specified limit value and
• Controlling the rotary drive assigned to the winch arm with additional consideration of this comparison in such a way that if the limit value for the change in rotational position is exceeded by the active compensating rotational movement of the winch arm, the operational rope tension is at least largely approximated to the predetermined setpoint range.

An advantage of this embodiment can be that a rope lay or a sudden decrease in rope tension is detected even earlier and more reliably. The change in the rotational position of the winch arm can be caused by a rope lay, i.e. by a sudden snapping out of the winch rope from a temporary fixation on a slope to be prepared.

The detection of a change in the rotational position of the winch arm in the winch operation of the winch arrangement occurs simultaneously with the detection of a change in rope tension, so that the rotary drive is initially deactivated here too. The winch arm can therefore be freely rotated around the vehicle's vertical axis. Detecting a change in the rotational position of the winch arm also requires a time-dependent detection of a rotational position of the winch arm using basically known measuring methods. The change in rotational position of the winch arm can be defined by a change in a rotation angle relative to a vehicle longitudinal axis over a predetermined period of time. The change in rotational position of the winch arm can be recorded both as rotational angular velocity and as rotational angular acceleration. The specified limit value for the change in rotational position specifies a value which, if exceeded, will result in a rope lay or a sudden decrease in the winch rope tension is. It is possible to specify several limit values for a corresponding rotational angular velocity and/or a corresponding rotational angular acceleration.

The time-dependent change in rotational position of the winch arm is compared with the specified limit value for the change in rotational position. This comparison is taken into account in addition to the comparison already described above of the detected change in rope tension of the winch rope with the specified limit value for the change in rope tension. This means that the rotary drive assigned to the winch arm is only controlled or activated in order to at least largely approximate an actual value of the operational rope tension to the specified setpoint range through the active compensating rotational movement of the winch arm when both the limit value for the change in rotational position is exceeded and the limit value for the change in rotational position is not exceeded Limit value for the change in rope tension, especially at the same time, is present. If several limit values are specified for the rotational angular velocity and the rotational angular acceleration, the rotary drive is preferably activated when a first limit value is exceeded.

In one embodiment of the invention, the active compensating rotational movement of the winch arm takes place in the same direction or in the opposite direction to the change in rotational position of the winch arm. The change in the rotational position of the winch arm is a passive rotational movement of the winch arm and can take place in a specific direction of rotation depending on the rotational position of the winch arm and the direction of travel of the snow groomer. The active compensating rotational movement of the winch arm occurs either in the same direction or in the opposite direction to this direction of rotation.

If the active compensating rotational movement occurs in the opposite direction to the change in the rotational position of the winch arm, the passive rotational movement of the winch arm is braked and/or stopped by controlling the rotary drive and then rotated in the opposite direction until the actual value of the operational rope tension is in or close to the specified setpoint range at least largely approximated.

If the active compensating rotational movement occurs in the same direction, then the passive rotational movement of the winch arm caused by the decrease in the winch rope tension is not initially braked or stopped by activating the rotary drive, but continues to be rotated in the same direction until the actual value of the operational rope tension is in the specified setpoint range or at least comes close to this.

In one embodiment of the invention, an angle of rotation of the winch arm is detected relative to a vehicle longitudinal axis, which is determined when detecting the change in rotational position of the winch arm is taken into account in the winch operation of the winch arrangement. Detecting the angle of rotation of the winch arm can be done using basically known measuring methods.

In a further development of the invention, in order to detect the change in rope tension of the winch rope in the winch operation of the winch arrangement, a tensile force on the winch arrangement is recorded as a function of time. The tensile force on the winch arrangement can be detected at a front end region of the winch arm using basically known measuring methods.

In a further development of the invention, the active compensating rotational movement of the winch arm takes place relative to a plane spanned by the vehicle's vertical axis and a stationary anchor point of the winch rope in an angular amount range between 0° and 90°. This means that the active compensation rotational movement occurs relative to the spanned plane in an angular range of -90° to +90°. In the plane spanned by the vehicle vertical axis and the stationary anchor point of the winch rope there is a straight and therefore direct connection between the winch arm and the stationary anchor point. If the winch arm is in this plane, then this also applies to the winch rope anchored to the stationary anchor point.

• Ansteuern des Drehantriebs derart, dass sich der Windenarm durch eine aktive Rückbewegung unter Berücksichtigung des Sollwertbereichs für die betriebsbedingte Seilspannung zu einer von der Fahrzeughochachse und einem stationären Ankerpunkt des Windenseils aufgespannten Ebene hin ausrichtet.

In a further development of the invention, the method has the following further step after the active compensating rotational movement of the winch arm:

• Controlling the rotary drive in such a way that the winch arm aligns itself towards a plane spanned by the vehicle's vertical axis and a stationary anchor point of the winch rope by an active return movement, taking into account the setpoint range for the operational rope tension.

Activating the rotary drive corresponds to switching a direction of rotation of the rotary drive, since the active return movement of the winch arm takes place in the opposite direction to the active compensating rotary movement of the winch arm. By adjusting a driving speed of the snow groomer and/or by adjusting a winding speed of the winch rope, the rope tension can be additionally controlled and preferably kept in the setpoint range for the operational rope tension of the winch rope. After the active return movement of the winch arm, both the tensioned winch rope and the winch arm itself lie in the above-mentioned tensioned plane and thus in a direct alignment with the stationary anchor point.

• Ansteuern des Drehantriebs derart, dass dieser die Drehbarkeit des Windenarms freigibt.

In one embodiment of the invention, the method has the following further step after the active return movement of the winch arm:

• Controlling the rotary drive in such a way that it enables the winch arm to rotate.

Activating the rotary drive corresponds to deactivating the rotary drive. Although the rotary drive preferably remains mechanically connected to the winch arm, it is switched to an almost pressure-free circulation. This means that after this step the winch arm is again freely, in particular essentially resistance-free, rotatably mounted and aligns itself depending on a tensile force acting on the winch rope between the anchor point and the winch arm.

For the device according to the invention it is provided that a sensor system is provided for detecting a change in rope tension of the winch rope in the winch operation of the winch arrangement. In addition, an electronic data processing system is provided which has a data memory in which the data of the setpoint range for an operational rope tension and the limit value for the change in rope tension are stored, and which is coupled to the sensor system in order to activate the control device if the limit value for the change in rope tension is undershot of the rotary drive in such a way that the operational rope tension at least largely approaches the specified setpoint range through an active compensating rotational movement of the winch arm.

The sensor system for detecting a change in rope tension of the winch rope is designed for time-dependent detection of a rope tension of the winch rope. For this purpose, the sensor system can include a time recording unit or be assigned to one. The sensor system, in particular the time recording unit, enables the data recorded by the sensor system to be assigned to different times or periods of time. This makes it possible to calculate a pattern for a rope lay in connection with corresponding changes in the rope tension of the winch rope. If this pattern is extrapolated into the future, a prediction model for a rope strike can be derived. The data processing system has access to the data stored in the data memory of the setpoint range for an operational rope tension and the limit value, based on which a comparison is made with the data recorded by the sensor system.

The solution according to the invention is suitable for winch arrangements in which the winch arm is arranged in a rotationally fixed manner on the winch arrangement. In such an embodiment, the winch arm is located together with the winch arrangement or the winding device Snow groomer rotatably mounted. However, the solution according to the invention can also be used in winch arrangements in which the winding device for the winch cable is arranged fixed to the vehicle. In these winch arrangements, the winch arm itself is rotatably mounted relative to the vehicle-mounted arrangement of the winding device.

In a further development of the invention, a further sensor system is provided in the device for detecting a change in the rotational position of the winch arm in the winch operation of the winch arrangement. In addition, the data processing system has a data memory in which the limit value for the change in rotational position is stored, and is coupled to the further sensor system in order to control the control device of the rotary drive in such a way that the active compensating rotational movement of the winch arm occurs when the limit value for the change in rotational position is exceeded the operational rope tension at least largely approximates the specified setpoint range. This represents a structurally and functionally advantageous implementation of the device.

The further sensor system for detecting a change in the rotational position of the winch arm is designed for time-dependent detection of a rotational position of the winch arm. For this purpose, the additional sensor system can include a time recording unit as described above or can be assigned to one. The data recorded by this sensor system can also be taken into account in the prediction model for a rope lay. The data processing system has access to the data stored in the data memory of the setpoint range for an operational rope tension and the limit value, which is used to compare it with the data recorded by the other sensors.

In a further development of the invention, the further sensor system for detecting the rotational position of the winch arm has a rotation angle sensor which is designed to detect a rotation angle of the winch arm relative to a vehicle longitudinal axis.

In a further development of the invention, the sensor system for detecting the cable tension of the winch cable is arranged in the winch arm, in particular at a front end region of the winch arm, and/or has a tensile force sensor for detecting a tensile force on the winch arrangement.

The snow groomer according to the invention has the device according to the invention. Such a snow groomer has significantly increased operational reliability in winch operation, both in terms of the driving function and the winch function and the functions of the attachments.

Fig. 1

schematisch in einer Seitenansicht eine Pistenraupe mit einer Vorrichtung zur Steuerung einer Windenanordnung,

Fig. 2

schematisch in einer Seitenansicht die Pistenraupe gemäß der Fig. 1 im Windenbetrieb mit einem auf einen stationären Ankerpunkt ausgerichteten Windenarm und einem verankerten Windenseil,

Fig. 3A und 3B

schematisch in einer Draufsicht das Pistenfahrzeug gemäß der Fig. 2 mit unterschiedlichen Fahrtrichtungen der Pistenraupe relativ zu dem Ankerpunkt,

Fig. 4

schematisch in einer Seitenansicht die Pistenraupe gemäß der Fig. 2 mit einem temporären Fixierpunkt des Windenseils und

Fig. 5A bis 5D

schematisch in einer Draufsicht den zeitlichen Ablauf des erfindungsgemäßen Verfahrens zur Steuerung der Windenanordnung der Pistenraupe.

A preferred embodiment of the invention is shown in the drawings. These and further embodiments of the invention are explained in more detail below. Show:

Fig. 1

schematically a side view of a snow groomer with a device for controlling a winch arrangement,

Fig. 2

schematically in a side view the snow groomer according to Fig. 1 in winch operation with a winch arm aligned to a stationary anchor point and an anchored winch rope,

Figures 3A and 3B

schematically in a top view the snow groomer according to Fig. 2 with different directions of travel of the snow groomer relative to the anchor point,

Fig. 4

schematically in a side view the snow groomer according to Fig. 2 with a temporary fixation point for the winch rope and

5A to 5D

schematically in a top view the timing of the method according to the invention for controlling the winch arrangement of the snow groomer.

A snow groomer 2 after Fig. 1 has a crawler chassis 18 in a generally known manner, which is assigned to a chassis (unspecified). The chassis has a driver's cab 19 on the front. A clearing blade 20 is provided as a front attachment. A rear tiller 21 is provided as a rear attachment, which is adjustable and detachably held on the chassis of the snow groomer 2 via an unspecified rear equipment carrier.

The snow groomer 2 further has a device for controlling a winch arrangement 1 of the snow groomer 2. The winch arrangement 1 is rotatably attached to the chassis of the snow groomer 2 about a vehicle vertical axis FH, preferably via a ball-bearing slewing ring, and has a winding device 6, which is assigned a drive device 8 for a winch rope 3 for introducing a tensile force Fz onto the winch rope 3, wherein the winch rope 3 can be wound onto the winding device 6 or unwound from the winding device 6. The winch rope 3 has, on a free end region 7 facing away from the winding device 6, an unspecified locking device, preferably a hanging hook, via which the winch rope 3 can be anchored to a stationary anchor point A, as in particular in the Fig. 2 is visible. The winch arrangement 1 further has a winch arm 4 for feeding the winch rope 3 to the winding device 6. The winch arm 4 enables the winch rope 3 to be guided over a driver's cab 19 Snow groomer 2 away, so that a driver of the snow groomer 2 has the winch rope 3 in his field of vision, at least when the snow groomer 2 is oriented uphill, as in the Fig. 2 is shown. The winch arrangement 1 further has a rotary drive 5 for generating active rotational movements of the winch arrangement 1 or the winch arm 4 about the vehicle vertical axis FH. In the present case, the rotary drive 5 is preferably designed as an electric or hydraulic motor. For this purpose, the snow groomer 2 has a control device 9 for controlling the rotary drive 5 of the winch arrangement 1 or the winch arm 4, the rotary drive 5 preferably acting via a pinion on an at least partially circumferential toothing provided on the winch arrangement 1. This enables an active rotational movement of the winch arrangement 1 or the winch arm 4. The toothing is coplanar with a plane of the slewing ring. The slewing ring preferably lies in a horizontal plane.

The snow groomer 2 or the device for controlling the winch arrangement 1 of the snow groomer 2 further has a sensor system 10 for detecting a change in rope tension of the winch rope 3 in a winch operation of the winch arrangement 1. In addition, an electronic data processing system 11 is provided which has a data memory 12 in which the data of a setpoint range for an operational rope tension and a limit value for the change in rope tension are stored. The electronic data processing system 11 is coupled to the sensor system 10 in order to instruct the control device 9 of the rotary drive 5 if the limit value for the change in rope tension is undershot in such a way that the operational rope tension is at least within a predetermined setpoint range through an active compensating rotational movement of the winch arrangement 1 or the winch arm 4 largely approximated.

In the Fig. 2 the snow groomer 2 is shown on a steep ski slope P in the winch mode with a direction of travel FR uphill or uphill. In winch operation, the snow groomer 2 is anchored to the stationary anchor point A with the free end region 7 of the winch rope 3 facing away from the winding device 6, so that the snow groomer 2 can drive on the slopes with traction support from the tensioned winch rope 3. The stationary anchor point A is designed as a pole anchored in the terrain and is attached above a ski slope P.

The Figures 3A and 3B show the snow groomer 2 in a top view with different directions of travel FR of the snow groomer 2 relative to the stationary anchor point A. The rotatability of the winch arrangement 1 or the winch arm 4 of the snow groomer 2 is enabled by the rotary drive 5. This means that the rotary drive 5 is still mechanically connected to the winch arm 4, but is switched to an almost pressure-free circulation. The winch arm 4 directs therefore due to its free, essentially resistance-free rotation in the direction of a tensile force Fz of the winch cable 3 or towards the stationary anchor point A. The winch arm 4 lies in a plane E spanned by the vehicle vertical axis FH and the stationary anchor point A of the winch rope 3. In the Fig. 3A the direction of travel FR or a direct lane of the snow groomer 2 is aligned with the stationary anchor point A. The winch arrangement 1 or the winch arm 4 of the snow groomer 2 is in a zero position in this situation. This means that the winch arm 4 runs along the vehicle's longitudinal axis FL or in the direction of travel FR of the snow groomer 2. In the Fig. 3B The stationary anchor point A is laterally offset from the direction of travel FR or the direct path of the snow groomer 2. In this situation, the winch arrangement 1 or the winch arm 4 of the snow groomer 2 aligns itself with the laterally offset anchor point A and rotates relative to the zero position or the vehicle longitudinal axis FL by the angle of rotation α. The Fig. 4 shows the plane E spanned by the vehicle vertical axis FH of the snow groomer 2 and the stationary anchor point A of the winch rope 3 in a side view. In plane E there is a straight connection between the winch arm 4 or the vehicle vertical axis FH and the stationary anchor point A.

In the Fig. 4 a temporary fixing point T of the winch rope 3 is also shown. The temporary fixation point T of the winch rope 3 arises in particular when the winch rope 3 is temporarily fixed to a terrain contour or a snow surface elevation of a ski slope P with a lateral offset to the direct alignment or to the plane E of the snow groomer 2, as in particular in the Fig. 5A is visible. In this situation, the winch arrangement 1 or the winch arm 4 is deflected to the side or in the direction of the temporary fixing point T due to the rotatable bearing. If the winch rope 3 is released from its temporary fixation T, the winch rope 3 suddenly snaps in a direct direction between the snow groomer 2 and the stationary anchor point A or in the direction of the plane E due to static pre-tensioning forces of the winch rope 3, as in the Fig. 5B is visible. This is also referred to below as rope lay. The winch arm 3 rotates with the winch rope 3 in this direct direction.

The 5A to 5D show in a top view the time sequence of the method according to the invention for controlling the winch arrangement 1 of the snow groomer 2. In the example shown, the stationary anchor point A is not in alignment with the vehicle longitudinal axis FL or the direction of travel FR of the snow groomer 2, so that the vehicle longitudinal axis FL is not lies in level E, especially in the Fig. 5A is visible. In addition, as already mentioned, the temporary fixation point T is neither in alignment with the vehicle's longitudinal axis FL or the direction of travel FR of the snow groomer 2 nor in alignment with plane E.

If a rope lay occurs during winch operation of the winch arrangement 1, then this leads to a change in the rope tension of the winch rope 3. This change in the rope tension of the winch rope 3 is detected by the sensor system 10 for detecting a change in rope tension of the winch rope 3. The electronic data processing system 11 specifies a setpoint range for an operational rope tension and a limit value for the change in rope tension, these data being stored in a data memory 12. The data processing system 11 compares the detected change in rope tension of the winch rope 3 with the specified limit value. If the detected change in rope tension of the winch rope 3 falls below the limit value for the change in rope tension, then the data processing system 11 instructs the control device 9 of the rotary drive 5 in such a way that the operational rope tension at least largely approaches a predetermined setpoint range through an active compensating rotational movement of the winch arrangement 1 or the winch arm 4 .

In an advantageous implementation, the device for controlling the winch arrangement 1 of the snow groomer 2 has a further sensor system 13 for detecting a change in the rotational position of the winch arm 4 in the winch operation of the winch arrangement 1. Because when the rope is laid, as already described above, the freely rotatable winch arm 4 is rotated in the direction of plane E, as in the Fig. 5B is visible. The data processing system 11 specifies a limit value for the change in rotational position, which is stored in a data memory 14 assigned to it. For this purpose, the data processing system 11 is coupled to the further sensor system 13. The data processing system 11 compares the detected change in rotational position of the winch arm 4 with the specified limit value. This comparison is taken into account in addition to the above-mentioned comparison of the detected change in rope tension of the winch rope 3 with the specified limit value.

In other words: If the detected change in rope tension of the winch rope 3 falls below the predetermined limit value and if the change in rotational position of the winch arm 4 exceeds the predetermined limit value, then the data processing system 11 instructs the control device 9 of the rotary drive 5 in such a way that an active compensating rotational movement of the winch arrangement 1 or of the winch arm 4, the operational rope tension at least largely approaches a predetermined setpoint range. In the example shown, the operational rope tension has reached the specified setpoint range. The winch rope 3 is in a tensioned state between the winch arm 4 and the stationary anchor point A, as in the Fig. 5C is visible.

In an advantageous embodiment, as in the example shown, the active compensating rotational movement of the winch arm 4 takes place in the opposite direction to the change in rotational position of the winch arm 4. In the Fig. 5B a passive rotational movement of the winch arm 4 is shown in a direction of rotation DR. In this exemplary embodiment, the direction of rotation DR corresponds to the passive rotational movement of the winch arm 4 in a counterclockwise direction. The passive rotational movement of the winch arm 4 is braked or stopped by controlling or activating the rotary drive 5 and then rotated in the opposite direction. The winch rope 3 is preferably tensioned due to the opposite rotational movement of the winch arm 4. Accordingly, in the example shown, the active compensation rotational movement of the winch arm 4 takes place clockwise.

In alternative embodiments, the active compensation rotational movement of the winch arm 4 is in the same direction as the change in rotational position of the winch arm 4.

In advantageous embodiments, a rotation angle α of the winch arm 4 is detected relative to a vehicle longitudinal axis FL, as in the Fig. 3B is visible. The angle of rotation α is taken into account when detecting the change in rotational position of the winch arm 4 in the winch operation of the winch arrangement 1. For this purpose, the further sensor system 13 for detecting the rotational position of the winch arm 4 has a rotation angle sensor 15, which is designed to detect a rotation angle α of the winch arrangement 1 or the winch arm 4 relative to a vehicle longitudinal axis FL.

In an advantageous implementation, the tensile force Fz on the winch arrangement 1 is recorded as a function of time, which is taken into account when detecting the change in rope tension of the winch rope 3 in the winch operation of the winch arrangement 1. For this purpose, the sensor system 10 for detecting the rope tension of the winch rope 3 is arranged in the winch arm 4, in particular at a front end region 16 of the winch arm 4, and/or has a tensile force sensor 17 for detecting the tensile force Fz on the winch arrangement 1. In the exemplary embodiment shown, the tensile force sensor 17 is arranged at the front end region 16 of the winch arm 4 on a deflection roller 22, as in the Fig. 1 is visible. The deflection roller 22 is followed by a further deflection roller 23 starting from the winch arrangement 1 in the direction of the front end region 16, so that the tensile force Fz is detected on the second deflection roller 22 of the winch arm 4 seen from the front end region 16 of the winch arm 4.

In further advantageous embodiments, the active compensating rotational movement of the winch arm 4 takes place relative to the plane E spanned by the vehicle vertical axis FH and the stationary anchor point A of the winch rope 3 in an angular amount range β between 0 ° and 90°. This means that the active compensation rotational movement of the winch arm 4 takes place relative to the spanned plane E in an angular range of -90° to +90°, as in the Fig. 5A is visible.

In an advantageous implementation, after the active compensating rotational movement of the winch arm 4, the rotary drive 5 of the winch arrangement 1 or the winch arm 4 is controlled in such a way that the winch arm 4 moves towards level E through an active return movement, taking into account the setpoint range for the operational rope tension aligned, as in the Fig. 5D is visible. By adjusting or reducing a driving speed of the snow groomer 2 and/or by adjusting or increasing a winding speed or a rotational speed of the winding device 6 of the winch rope 3, the rope tension can be kept in the setpoint range for the operational rope tension of the winch rope 3. After the active return movement of the winch arm 4, both the tensioned winch cable 3 and the winch arm 4 itself lie in plane E and thus in a direct alignment with the stationary anchor point A. Since the stationary anchor point A is not in line with the vehicle longitudinal axis FL of the snow groomer 2 is located, the winch arm 4 is slightly rotated relative to the vehicle longitudinal axis FL.

In advantageous embodiments, after the active return movement of the winch arm 4, the rotary drive 5 of the winch arrangement 1 or the winch arm 4 is controlled in such a way that it enables the rotatability of the winch arm 4. The winch arrangement 1 or the winch arm 4 can then be freely rotated again.

Claims (13)

Method for controlling a winch arrangement (1) of a snow groomer (2), the winch arrangement (1) having a winch cable (3) and a winch arm (4) guiding the winch cable (3), which is rotatably mounted about a vehicle vertical axis (FH), with the following steps: - detecting a change in a rope tension of the winch rope (3) in a winch operation of the winch arrangement (1), - specifying a target value range for an operational rope tension, - specifying a limit value for the change in rope tension, - Comparison of the recorded change in rope tension of the winch rope (3) with the specified limit value and - Controlling a rotary drive (5) assigned to the winch arm (4), taking into account the comparison in such a way that if the limit value for the change in rope tension is undershot by an active compensating rotational movement of the winch arm (4), the operational rope tension is at least largely approximated to the predetermined setpoint range. Method according to claim 1, further characterized in that the method comprises the following further steps: - detecting a change in a rotational position of the winch arm (4) in the winch operation of the winch arrangement (1), - specifying a limit value for the change in rotational position, - Comparison of the detected change in rotational position of the winch arm (4) with the specified limit value and - Controlling the rotary drive (5) assigned to the winch arm (4), taking this comparison into account in such a way that if the limit value for the change in rotational position is exceeded by the active compensating rotational movement of the winch arm (4), the operational rope tension is at least largely approximated to the predetermined setpoint range. Method according to claim 2, further characterized in that the active compensating rotational movement of the winch arm (4) takes place in the same direction or in the opposite direction to the change in rotational position of the winch arm (4). Method according to one of claims 2 or 3, further characterized in that a rotation angle (α) of the winch arm (4) is detected relative to a vehicle longitudinal axis (FL), which is taken into account when detecting the change in rotational position of the winch arm (4) in the winch operation of the winch arrangement (1). Method according to one of the preceding claims, further characterized in that in order to detect the change in rope tension of the winch rope (3) in the winch operation of the winch arrangement (1), a tensile force (Fz) on the winch arrangement (1) is detected as a function of time. Method according to one of the preceding claims, further characterized in that the active compensating rotational movement of the winch arm (4) relative to a plane (E) spanned by the vehicle vertical axis (FH) and a stationary anchor point (A) of the winch rope (3) in an angular amount range ( β) between 0° and 90°. Method according to one of the preceding claims, further characterized in that the method has the following further step after the active compensating rotational movement of the winch arm (4): - Controlling the rotary drive (5) in such a way that the winch arm (4) moves through an active return movement, taking into account the setpoint range for the operational rope tension, to a plane spanned by the vehicle vertical axis (FH) and a stationary anchor point (A) of the winch rope (3). (E) aligned. Method according to claim 7, further characterized in that the method comprises the following further step after the active return movement of the winch arm: - Controlling the rotary drive (5) in such a way that it enables the winch arm (4) to rotate. Device for carrying out a method according to at least one of the preceding claims 1 to 8, comprising: - a winch arrangement (1). - a winding device (6) for storing and winding the winch rope (3), which can be anchored to a stationary anchor point (A) on a free end region (7) facing away from the winding device (6), - a drive device (8) assigned to the winding device (6) for introducing tensile forces (Fz) onto the winch rope (3), - a winch arm (4) for feeding the winch rope (2) to the winding device (6), the winch arm (4) being rotatably mounted about a vehicle vertical axis (FH) and - a rotary drive (5) assigned to the winch arm (4) for generating active rotational movements of the winch arm (4) about the vehicle vertical axis (FH), and - a control device (9) for controlling the rotary drive (5) of the winch arm (4), characterized in that - a sensor system (10) is provided for detecting a change in rope tension of the winch rope (3) in the winch operation of the winch arrangement (1) and - an electronic data processing system (11) is provided which has a data memory (12) in which the data of the setpoint range for an operational rope tension and the limit value for the change in rope tension are stored, and which is coupled to the sensor system (10) in order to If the limit value for the change in rope tension is undershot, the control device (9) of the rotary drive (5) is controlled in such a way that the operational rope tension at least largely approaches the predetermined setpoint range through an active compensating rotational movement of the winch arm (4). Device according to claim 9, further characterized in that - a further sensor system (13) is provided for detecting a change in the rotational position of the winch arm (4) in the winch operation of the winch arrangement (1) and - the data processing system (11) has a data memory (14) in which the limit value for the change in rotational position is stored, and is coupled to the further sensor system (13) in order to control the control device (9) of the rotary drive if the limit value for the change in rotational position is exceeded (5) to be controlled in such a way that the operational rope tension at least largely approaches the specified setpoint range due to the active compensating rotational movement of the winch arm (4). Device according to claim 10, further characterized in that the further sensor system (13) for detecting the rotational position of the winch arm (4) has a rotation angle sensor (15) which is used to detect a rotation angle (α) of the winch arm (4) relative to a vehicle longitudinal axis ( FL) is trained. Device according to one of claims 9 to 11, further characterized in that the sensor system (10) for detecting the rope tension of the winch rope (3) is arranged in the winch arm (4), in particular at a front end region (16) of the winch arm (4). and/or has a tensile force sensor (17) for detecting a tensile force (Fz) on the winch arrangement (1). Snow groomer with a device according to at least one of the preceding claims 9 to 12.

Images