Crane, and method for controlling such a crane

Abstract

The present invention relates to a crane, in particular to a revolving tower crane, having a load suspension means attached to a hoist rope, drive devices for moving a plurality of crane elements and for traveling the load suspension means, a control apparatus for controlling the drive devices such that the load suspension means travels along a travel path, and an oscillation damping device for damping oscillation movements of the load suspension means, wherein said oscillation damping device has a control module for influencing the control of the drive devices in dependence on oscillation-relevant criteria. It is proposed not only to take account of the actual oscillation movement of the rope per se in the oscillation damping measures, but also the dynamics of the steel construction of the crane and its drivetrains.

Claims

1. A tower crane subject to dynamic loads during operation comprising: a tower that supports a boom on which a trolley is displaceable, wherein one or more structural elements of the tower crane experience elastic deformations and movements in response to being subject to the dynamic loads; a load suspension means attached to a hoist rope running from the trolley, wherein at least one of the load suspension means or the hoist rope experience oscillation movements resultant from the dynamic loads; drive devices for moving one or more crane elements used for traveling the load suspension means; a control apparatus for controlling the drive devices such that the load suspension means travels along a travel path; and an oscillation damping device for damping the oscillation movements of the load suspension means and/or of the hoist rope as a result of the dynamic loads, the oscillation damping device comprising: determination means comprising a sensor system including at least one deformation sensor, the determination means for determining the elastic deformations and movements of the one or more structural elements of the tower crane under the dynamic loads during operation of the tower crane; and a control module for automatically influencing the movement of one or more of the crane elements via control of the drive devices in response to the determined elastic deformations and movements.

2. The tower crane in accordance with claim 1, wherein one of the structural elements is selected from the group consisting of the tower and the boom; and wherein the determination means are configured to determine deformations and movements of at least one of the tower or the boom during operation of the tower crane.

3. The tower crane in accordance with claim 1, wherein structural elements that experience the elastic deformations and movements include the tower and a drivetrain part; and wherein the determination means are configured to determine deformations and movements of the tower and drivetrain part during operation of the tower crane.

4. The tower crane in accordance with claim 1, wherein the determination means determines the elastic deformations and movements of the tower and one or more other structural elements; wherein at least one deformation sensor is attached to the tower; and wherein, while the tower crane is configured to allow the tower and the one or more other structural elements to experience the elastic deformations and movements, the oscillation damping device dampens the oscillation movements of the load suspension means and/or of the hoist rope resultant from the elastic deformations and movements of the tower and the one or more other structural elements.

5. The tower crane in accordance with claim 4, wherein the determination means further comprise at least one of: an estimation device for estimating the deformations and movements of the tower and the one or more other structural elements during operation of the tower crane on the basis of digital data of a data model describing the tower crane; or a calculation unit that calculates the deformations and movements of the tower and the one or more other structural elements on the basis of a stored calculation model in dependence on control commands input at a control station.

6. The tower crane in accordance with claim 4, wherein the sensor system further comprises a dynamic parameter sensor for detecting dynamic parameters of the tower and the one or more other structural elements.

7. The tower crane in accordance with claim 6, wherein the sensors are selected from the group consisting of: an inclination sensor and/or acceleration sensor for detecting tower inclinations and/or tower speeds; a rotational speed sensor and/or rotational acceleration sensor for detecting the rotational speed and/or rotational acceleration of the boom; a pitching movement sensor for detecting pitching movements and/or pitching accelerations of the boom; a rope speed sensor and/or rope acceleration sensor for detecting rope speeds and/or rope accelerations of the hoist rope; and a combination thereof.

8. The tower crane in accordance with claim 4 further comprising a detection device for detecting a deflection of the hoist rope and/or of the load suspension means with respect to a vertical; wherein the control module of the oscillation damping device is further configured to influence the control of the drive devices in dependence on the determined deflection of the hoist rope and/or of the load suspension means with respect to the vertical.

9. The tower crane in accordance with claim 8 further comprising an image evaluation device; wherein the detection device comprises an imaging sensor system; and wherein the image evaluation device is for evaluating an image provided by the imaging sensor system with respect to the position of the load suspension means in the provided image and for determining the deflection of the load suspension means and/or of the hoist rope and/or of the deflection speed with respect to the vertical.

10. The tower crane in accordance with claim 9, wherein the imaging sensor system comprises a camera configured to look substantially straight down in the region of a trolley of the hoist rope.

11. The tower crane in accordance with claim 4, wherein the oscillation damping device further comprises a filter device and/or observation device for influencing adjustment values of drive regulators for controlling the drive devices, with the filter device and/or observer device being configured to obtain the adjustment values of the drive regulators and the detected and/or estimated movements of crane elements and/or deformations and/or movements of the tower and the one or more other structural elements that occur during operation of the tower crane as input values and to influence the adjustment values of the drive regulators in dependence on the dynamically induced movements of crane elements and/or deformations of the tower and the one or more other structural elements obtained for specific adjustment values of the drive regulators.

12. The tower crane in accordance with claim 11, wherein the filter device and/or observer device is configured as a Kalman filter.

13. The tower crane in accordance with claim 12, wherein detected and/or estimated and/or calculated and/or simulated functions that characterize dynamics of the tower and the one or more other structural elements are implemented in the Kalman filter.

14. The tower crane in accordance with claim 4, wherein the oscillation damping device further comprises a position sensor system that is configured to detect the load suspension means relative to a fixed global coordinate system and/or is configured to position the load suspension means relative to a fixed global coordinate system.

15. The tower crane in accordance with claim 4, wherein the oscillation damping device further comprises an oblique pull regulator and is configured to actuate the drive devices for moving the crane elements and for traveling the load suspension means such that the hoist rope, where possible, is perpendicular to suspended load, even if the tower crane deforms due to an increasing load torque and/or due to increasing transverse forces and/or increasing transverse twisting torques.

16. The tower crane in accordance with claim 1, wherein structural elements that experience the elastic deformations and movements include the tower and drivetrain parts; wherein at least one of the drivetrain parts is selected from the group consisting of slewing gear parts and trolley drive parts; and wherein the determination means are configured to determine deformations and/or movements of the tower and drivetrain parts during operation of the tower crane.

17. A method comprising: controlling drive devices of a tower crane subject to dynamic loads during operation for moving one or more crane elements used for traveling a load suspension means along a travel path, the load suspension means attached to a hoist rope running from a trolley displaceable along a boom supported by a tower of the tower crane; and damping oscillation movements of the load suspension means and/or of the hoist rope resulting from the dynamic loads; wherein the damping comprises: determining elastic deformations and movements of the tower and one or more other structural elements of the tower crane in response to being subject to the dynamic loads that occur during operation of the tower crane; and automatically influencing the movement of one or more of the crane elements via control of the drive devices in response to the determined deformations and movements; wherein a control apparatus performs the controlling; wherein an oscillation damping device performs the damping; wherein a determination means comprising a sensor system including at least one deformation sensor attached to the tower performs the determining; wherein a control module performs the automatically influencing; and wherein, while the tower crane is configured to allow the tower and the one or more other structural elements to experience the elastic deformations and movements, the step of dampening dampens the oscillation movements of the load suspension means and/or of the hoist rope resultant from the elastic deformations and movements of the tower and the one or more other structural elements.

18. The method in accordance with claim 17, wherein the oscillation damping device comprises a Kalman filter to which adjustment values of drive regulators are supplied as input values for controlling the drive devices and crane movements and/or deformations and/or dynamically induced movements of the tower and the one or more other structural parts adopted with adjustment values of the drive regulators are supplied as input values, with the Kalman filter performing an influencing of the adjustment values of the drive regulators in dependence on the input values.

Description

(1) The invention will be explained in more detail in the following with reference to a preferred embodiment and to associated drawings. There are shown in the drawings:

(2) FIG. 1: a schematic representation of a revolving tower crane in which the lifting hook position and a rope angle with respect to the vertical are detected by an imaging sensor system and in which an oscillation damping device influences the control of the drive devices to prevent oscillations of the lifting hook and of its hoist rope;

(3) FIG. 2: a schematic representation of a Kalman filter of the oscillation damping device and the influencing of the adjustment parameters of the drive regulators carried out by it; and

(4) FIG. 3: a schematic representation of deformations and swaying shapes of a revolving tower crane under load and their damping or avoiding by an oblique pull regulation, wherein the partial view a.) shows a pitching deformation of the revolving tower crane under load and an oblique pull of the hoist rope linked thereto, the partial views b.) and c.) show a transverse deformation of the revolving tower crane in a perspective representation and in a plan view from above, and partial views d.) and e.) show an oblique pull of the hoist rope linked to such transverse deformations.

(5) As FIG. 1 shows, the crane can be configured as a revolving tower crane. The revolving tower crane shown in FIG. 1 can, for example, have a tower 201 in a manner known per se that carries a boom 202 that is balanced by a counter-boom 203 at which a counter-weight 204 is provided. Said boom 202 can be rotated by a slewing gear together with the counter-boom 203 about an upright axis of rotation 205 that can be coaxial to the tower axis. A trolley 206 can be traveled at the boom 202 by a trolley drive, with a hoist rope 207 to which a lifting hook 208 is fastened running off from the trolley 206.

(6) As FIG. 1 likewise shows, the crane 2 can here have an electronic control apparatus 3 that can, for example, comprise a control processor arranged at the crane itself. Said control apparatus 3 can here control different adjustment members, hydraulic circuits, electric motors, drive apparatus, and other pieces of working equipment at the respective construction machine. In the crane shown, they can, for example, be its hoisting gear, its slewing gear, its trolley drive, its boom/luffing drivewhere presentor the like.

(7) Said electronic control apparatus 3 can here communicate with an end device 4 that can be arranged at the control station or in the operator's cab and can, for example, have the form of a tablet with a touchscreen and/or joysticks, rotary knobs, slider switches, and similar operating elements so that, on the one hand, different information can be displayed by the control processor 3 at the end device 4 and conversely control commands can be input via the end device 4 into the control apparatus 3.

(8) Said control apparatus 3 of the crane 1 can in particular be configured also to control said drive apparatus of the hoisting gear, of the trolley, and of the slewing gear when an oscillation damping device 340 detects oscillation-relevant movement parameters.

(9) For this purpose, the crane 1 can have a detection device 60 that detects an oblique pull of the hoist rope 207 and/or deflections of the lifting hook 208 with respect to a vertical line 61 that passes through the suspension point of the lifting hook 208, i.e. the trolley 206. The rope pull angle can in particular be detected with respect to the line of gravity effect, i.e. the vertical 62, cf. FIG. 1.

(10) The determination means 62 of the detection device 60 provided for this purpose can, for example, work optically to determine said deflection. A camera 63 or another imaging sensor system can in particular be attached to the trolley 206 that looks perpendicularly downwardly from the trolley 206 so that, with a non-deflected lifting hook 208, its image reproduction is at the center of the image provided by the camera 63. If, however, the lifting hook 208 is deflected with respect to the vertical 61, for example by a jerky traveling of the trolley 206 or by an abrupt braking of the slewing gear, the image reproduction of the lifting hook 208 moves out of the center of the camera image, which can be determined by an image evaluation device 64.

(11) The control apparatus 3 can control the slewing gear drive and the trolley drive with the aid of the oscillation damping device 340 in dependence on the detected deflection with respect to the vertical 61, in particular while taking account of the direction and magnitude of the deflection, to again position the trolley 206 more or less exactly above the lifting hook 208 and to compensate or reduce oscillation movements or not even to allow them to occur.

(12) The oscillation damping device 340 for this purpose comprises determination means 342 for determining dynamic deformations of structural elements, wherein the control module 341 of the oscillation damping device 340 that influences the control of the drive device in an oscillation damping manner is configured to take account of the determined dynamic deformations of the structural elements of the crane on the influencing of the control of the drive devices.

(13) The determination means 342 can here comprise an estimation device 343 that estimates the deformations and movements of the machine structure under dynamic loads that result in dependence on control commands input at the control station and/or in dependence on specific control actions of the drive devices and/or in dependence on specific speed and/or acceleration profiles of the drive devices while taking account of circumstances characterizing the crane structure. A calculation unit 348 can in particular calculate the structural deformations and movements of the structural parts resulting therefrom using a stored calculation model in dependence on the control commands input at the control station.

(14) Alternatively or additionally, the oscillation damping device 340 can also comprise a suitable sensor system 344 by means of which such elastic deformations and movements of structural elements under dynamic loads are detected. Such a sensor system 344 can, for example, comprise deformation sensors such as strain gauges at the steel construction of the crane, for example the lattice structures of the tower 201 or of the boom 202. Alternatively or additionally, acceleration sensors and/or speed sensors can be provided to detect specific movements of structural elements such as pitching movements of the boom tip or rotational dynamic effects at the boom 202. Alternatively or additionally, inclination sensors or gyroscopes can also be provided at the tower 201, for example, in particular at its upper section at which the boom is supported, to detect the dynamics of the tower 201. Alternatively or additionally, motion sensors and/or acceleration sensors can also be associated with the drivetrains to be able to detect the dynamics of the drivetrains. For example, rotary encoders can be associated with the pulley blocks of the trolley 206 for the hoist rope and/or with the pulley blocks for a guy rope of a luffing boom to be able to detect the actual rope speed at the relevant point.

(15) As FIG. 2 shows, the oscillation damping device 340 comprises a filter device or an observer 345 that observes the crane reactions that are adopted with specific adjustment parameters of the drive regulators 347 and that influences the adjustment parameters of the regulator using the observed crane reactions while taking account of predetermined principles of a dynamic model of the crane that can generally have different properties and that can be acquired by analysis and simulation of the steel construction.

(16) Such a filter device or observation device 345b can in particular be configured in the form of a so-called Kalman filter 346 to which the adjustment values of the drive regulators 347 of the crane and the crane movements, in particular the rope pull angle with respect to the vertical 62 and/or its time change or the angular speed of said oblique pull are supplied as input values and which influences the adjustment values of the drive regulators 347 accordingly from these input values using Kalman equations that model the dynamic system of the crane structure, in particular its steel elements and drivetrains, to achieve the desired oscillation damping effect.

(17) In particular deformations and sway shapes of the revolving tower crane under load can be damped or avoided from the start by means of such an oblique pull regulation, as is shown by way of example in FIG. 3, with the partial view a.) there initially schematically showing a pitching deformation of the revolving tower crane under load as a result of a deflection of the tower 201 with the accompanying lowering of the boom 202 and an oblique pull of the hoist rope linked thereto.

(18) The partial views b.) and c.) of FIG. 3 further show by way of example in a schematic manner a transverse deformation of the revolving tower crane in a perspective representation and in a plan view from above with the deformations of the tower 201 and of the boom 202 occurring there.

(19) Finally, FIG. 3 shows an oblique pull of the hoist rope linked to such transverse deformations in its partial views d.) and e.).

(20) To counteract the corresponding sway dynamics, the oscillation damping device 430 can comprise an oblique pull regulation. The position of the lifting hook 208, in particular also its oblique pull with respect to the vertical, that is, the deflection of the hoist rope 207 with respect to the vertical, is in particular detected by means of the determination means 62 and is supplied to said Kalman filter 346.

(21) The positional sensor system can advantageously be configured to detect the load or the lifting hook 208 relative to a fixed global coordinate system and/or the oscillation damping device 430 can be configured to position the load relative to a fixed global coordinate system.

(22) An oblique pull regulation that eliminates or at least reduces a static deformation due to the attached load can be implemented by the load position detection here. To reduce the sway dynamics or even to not even allow them to arise at all, the oscillation damping device 430 can be configured to correct the slewing gear and the trolley chassis such that the rope is, where possible, always perpendicular to the load even when the crane inclines more and more to the front due to the increasing load torque.

(23) For example, on the lifting of a load from the ground, the pitching movement of the crane as a consequence of its deformation under the load can be taken into account and the trolley chassis can be subsequently traveled while taking account of the detected load position or can be positioned using a forward-looking estimation of the pitch deformation such that the hoist rope is in a perpendicular position above the load on the resulting crane deformation. The greatest static deformation here occurs at the point at which the load leaves the ground. An oblique pull regulation is then no longer required. In a corresponding manner, alternatively or additionally, the slewing gear can also be subsequently traveled while taking account of the detected load position and/or can be positioned using a forward-looking estimation of a transverse deformation such that the hoist rope is in a perpendicular position above the load on the resulting crane deformation.

(24) Such an oblique pull regulation can be reactivated by the operator at a later time who can thereby use the crane as a manipulator. He can hereby reposition the load simply by pressing and/or pushing. The oblique pull regulation here attempts to follow the deflection that is caused by the operator. A manipulation control can thereby be implemented.