Lifting device for lifting and handling a container

Abstract

A lifting device for lifting and handling a container, in particular a gantry crane, comprising a trolley (1) movable in a horizontal direction and a vertically movable container gripping means (10) connected to the trolley (1) via a plurality of hoisting ropes (2). The container gripping means (10) comprises a support structure (12) extending along a transverse plane, a gripping mechanism (14) for gripping a container, and a positioning means (20) for moving the support structure (12) relative to the trolley (1). The positioning means (20) comprises a translation mechanism configured to move the support structure independently relative to the trolley (1) along two orthogonal translation directions (X, Y) in the transverse plane, and a tilting mechanism configured to tilt the support structure (12) relative to the trolley (1) about at least a first tilting axis.wherein the translation mechanism comprises at least one actively driven movement unit (30, 32) connected to the support structure (12) and to which at least one hoist cable (2) is attached, for moving the support structure (12) relative to the trolley (1) along one of the translation directions (X, Y), while the movement unit (30, 32) is preferably pivotally connected to the support structure (12), and wherein the pivot axis is parallel to the transverse plane and / or parallel to the respective translation direction, characterized in that the tilting mechanism comprises a tilting frame (50) and the translation mechanism comprises at least two movement units (30) connected to opposite ends of the tilting frame (52) via pivot elements (52), each pivot element (52) being pivotally connected to the support structure (12) about a first pivot axis (54) parallel to the first tilt axis,while the tilting frame (50) is movable relative to the support structure (12) by means of a tilting actuator (56), in particular a hydraulic cylinder or a motor unit, wherein the motor unit preferably comprises a hydraulic or electric motor and / or a transmission.

Description

The present invention relates to a lifting device for lifting and transposing a container, in particular a gantry crane, according to the preamble of claim 1.Examples of embodiments known from the prior art can be seen in this connection, for example, from AT 520 091 A4, DE 199 57 823 A1 and DE 32 41 380 A1.Container lift portal cranes typically employ a spreader jack (or simply "spreader"; a mechanism for raising and lowering cargo containers) to enable secure connection to a container and lifting of a container(s). The spreader is usually mounted (over four to eight steel wire ropes) on a trolley which is moved along rails on the main beam of the crane. Traditionally, to position the spreader on a target container, the crane operator has to drive the complete crane construction and trolley into the correct position. Moving the construction / trolley, however, may result in the whole crane fluctuating, making the correct positioning of the spreader more difficult and time consuming during the final phases of container landing / gripping. In order to overcome this problem, it is more advantageous to move only the spreader itself (so-called micromovement) and not the entire crane construction or trolley during the final phases of the operation.Furthermore, with the introduction of container crane automation, it is now necessary to introduce means for accurately performing and controlling fine movements (micromovements) of such container turnover spreader.Current solutions for effecting such micromovements of the spreader consist of hybrid mechanisms in which the movement is achieved by several different subsystems within the mechanical system of the crane. Such solutions are complex and / or do not provide complete control over the spreader movement, often making container gripping and / or transshipment a difficult and time consuming task.It is therefore an object of the present invention to provide a solution for gripping and handling containers which is less complex and easier to handle.According to the invention, this object is achieved by providing a lifting device for lifting and transposing a container, in particular a gantry crane, having all the features of claim 1. The hoist according to the present invention comprises a trolley movable in a horizontal direction and a container gripping means vertically movable and connected to the trolley via a plurality of hoisting ropes (e.g., four or eight steel wire hoisting ropes). The container gripping means comprises a support structure extending along a transverse plane, a gripping mechanism for gripping a container, and a positioning means for moving the support structure relative to the trolley. Furthermore, the positioning means comprises a translation mechanism which is configured for independently moving the support structure with respect to the trolley along two orthogonal translation directions in the transverse plane. The positioning means further comprises a tilting mechanism configured to tilt the support structure relative to the trolley about at least a first tilting axis. The first tilting axis is in particular not a vertical axis. In addition, the translation mechanism has at least one actively driven movement unit for moving the carrier construction with respect to the trolley along one of the translation directions. The movement unit is connected to the carrier structure, preferably pivotably connected, and at least one lifting cable, preferably two lifting cables, is / are attached to the movement unit. The pivot axis is preferably parallel to the transverse plane and / or to the respective translation direction (i.e. the translation direction provided by the movement unit).The movement unit may be pivotally connected to the support structure by means of one or more bushes to form a pin connection or a pin connection. Preferably, maintenance-free and / or lubricant-free bushings are used. Such bushings are resilient in nature so that any deformation of the assembly can be accommodated under load conditions without compromising the integrity of the pin connection or overloading the components by mechanically clamping the pin connections.Preferably, the translation mechanism comprises at least one actively driven movement unit for each intended translation direction, i.e. at least two movement units that cause micromovements along the orthogonal translation directions. More than one movement unit can be used for each direction of translation.The explanations and features listed in the following description regarding a moving unit apply to all moving units in embodiments using more than one moving unit, unless otherwise stated.The tilting mechanism according to the invention comprises a tilting frame and the translation mechanism comprises at least two movement units which are connected via pivot elements to opposite ends of the tilting frame. Each pivot element is pivotably connected to the carrier structure about a first pivot axis which is parallel to the first tilting axis. The tilting frame is movable with respect to the support structure by means of a tilting actuator, for example a hydraulic cylinder or a motor unit. In the latter case, the motor unit may comprise a hydraulic or electric motor and / or a transmission.The movement of the tilting frame by means of the tilting actuator leads to a rotation of the carrier structure and therefore of the gripping means about the first tilting axis. Preferably, the rotation of the support structure about the first tilting axis simultaneously rotates the tilting frame, since the movement units connected to the tilting frame are held by lifting cables and are furthermore pivotably connected thereto.Since the rotation about the first tilting axis (e.g. corresponding to a trimming rotation) is achieved by driving a mechanical tilting frame connected to the support structure, the rotation does not have to be initiated by handling individual lifting ropes, so that a stable and reliable tilting mechanism is provided for the support structure.The positioning means according to the embodiment of the invention enables simultaneous micromovements of the support structure and thus of the gripping mechanism, comprising translatory movements within a transverse plane (which, when the support structure is not tilted, corresponds to a horizontal plane) and a rotational movement about the first tilting axis. Therefore, the positioning means according to the invention provides at least three independent movements of the degree of freedom simultaneously.In such a range of movement, the gripping means of the lifting device, e.g. the spreader or the sheave traverse of a gantry crane, can be positioned so that in automatic operation it can effectively pick up or place its container load with high precision without the negative influence of a fluctuating lifting construction (due to working movement of the entire lifting device) as associated with conventional manual crane movement control systems. The gripping means can be precisely positioned with respect to a container to be received.Furthermore, the system according to the invention combines all the movement mechanisms which cause the different micromovements in an integrated positioning means, so that complex and space-consuming hybrid systems are avoided.In the case of a gantry crane, the transverse micromovements, i.e. the translation directions, preferably correspond to a movement of the support structure in a movement direction of the entire gantry (gantry displacement), which typically coincides with a long axis of the support structure or the spreader, and a movement of the support structure in a movement direction of the trolley along a main support of the gantry crane (trolley displacement), which typically coincides with a short axis of the support structure or the spreader. Moreover, the rotation about the first tilting axis preferably corresponds to a trimming rotation, while the first tilting axis is parallel to the trolley displacement direction.The precise positioning of the gripping means without having to move the entire lifting construction enables the automation of the container gripping and transposing process. In such an automation scenario, the lifting device preferably comprises a control device which receives information regarding a current position of the carrier construction / the gripping means, e.g. provided by a number of sensors, and which controls one or more actuators causing the various micromovements.The gripping means may be adapted to grip / connect to a standard ISO container(s) and / or comprise a number of corner locks for connection to a container.According to an embodiment of the invention, the tilting mechanism is configured to tilt the support structure relative to the trolley about a second tilting axis, wherein the second tilting axis is orthogonal to the first tilting axis. The rotation of the support structure about the second tilting axis may correspond to a skew. In the case of a gantry crane, the second tilting axis may be parallel to the gantry displacement direction.Preferably, the first and second tilting axes are parallel to the transverse plane and / or the translation directions (i.e. the first tilting axis is parallel to one of the translation directions, while the second tilting axis is parallel to the other translation direction).By providing a second microrotating movement of the support structure, the positioning means according to the invention enables a full movement with four degrees of freedom of the gripping means / support structure. The rotation about the second tilting axis may be effected by an actuator or by suitably regulating the length of a number of hoisting ropes. Furthermore, it is conceivable that the angle of rotation range about the second tilting axis (i.e. rotation) is as large as the angle of rotation range about the first tilting axis (i.e. trimming) or greater, which takes into account the fact that the second tilting axis is parallel to a long axis of the carrier construction and the first tilting axis is parallel to a short axis of the carrier construction. In certain embodiments, however, it is possible, depending on the geometry of the carrier construction and the movement directions, for the angle of rotation range about the first tilting axis to be greater than about the second tilting axis.According to a further embodiment, the movement unit comprises a housing element to which the at least one lifting cable is connected, and a linkage element connected to the carrier structure, while the linkage element is movably coupled to the housing element, preferably is slidably coupled. That is, the linkage element is connected to the housing element such that it can be moved, preferably displaced, with respect to the housing element.For this purpose, the slider may be slidably held or mounted inside the housing member. The housing member may comprise two or more component parts which may be assembled together to form the housing member, for example two halves. In an alternative embodiment, however, it is also conceivable for the housing element to be connected to the carrier structure while one or more lifting cables are connected to the slide piece, wherein the slide piece is held or mounted movably within the housing element in order to be movable with respect to the housing element.According to a further embodiment, the slide piece is movable with respect to the housing element by means of a shift actuator. The slider can be moved with respect to the housing element, preferably in a range of greater than or equal to ±100 mm, further preferably of ±200 mm or more, most preferably of ±300 mm or more. The shift actuator could be a hydraulic cylinder or a gear drive.In certain embodiments with two or more motion units per translation direction, all motion units associated with a certain translation direction could be moved by a common shift actuator or each of the motion units could be provided with a shift actuator.According to a further embodiment, the moving unit comprises a gear drive for moving the slide with respect to the housing element. The gear drive comprises a rack connected / mounted to / on the slider and a pinion disposed on or in the housing member and meshed with the rack. The pinion is connected to a drive shaft which can be driven by means of a motor unit. The drive shaft may be rotatably mounted in the housing by one or more drive shaft bearings. The motor unit preferably comprises a hydraulic or electric motor and / or a transmission. The motor unit can be considered to be part of the gear drive.Preferably, the gear drive is arranged such that the weight of the carrier construction and of the gripping means does not load or at least only partially load on the connection between pinion and rack. For this purpose, the slide should rest on a special support of the housing element, which receives the load of the support structure and of the gripping means.According to a further embodiment, the lifting device further comprises a displacement detection means for detecting a current relative position of the carrier construction. The displacement detection means is preferably arranged on a movement unit, in particular on the housing element or shift actuator and on the slide piece of said movement unit, in order to detect a relative distance between the housing element or shift actuator and the slide piece, which is representative of a current relative position of the carrier construction along the translation direction effected by said movement unit. Alternatively, the displacement detection means could be connected on the one hand to another part of the positioning means which moves together with the support structure, e.g. directly to the support structure, and / or on the other hand to another part of the positioning means which is connected to the lifting ropes, e.g. one of the lifting ropes themselves. The displacement detection means preferably comprises a position sensor, for example a cable actuator, in which the body is connected to the housing element / slide and the end of the cable is connected to the slide element / housing element.According to a further embodiment, the slide comprises at least one slide element which extends along the slide in the direction of movement and is in contact with at least one bearing shoe of the housing element. The connection and interaction between the slider(s) and the bearing shoe(s) of the moving unit guide the sliding movement of the slider with respect to the housing member. The slide member may comprise a track or rail extending along the slide member.The slider preferably comprises at least two lateral sliding elements arranged on opposite sides of the slider, each sliding element being in contact with at least one lateral bearing shoe of the housing element. Alternatively or additionally, the slide preferably comprises at least one lower slide element arranged on an underside of the slide element, which is in contact with at least one support shoe of the housing element. The connection between the lower slide element(s) and the support shoe(s) preferably takes up all or most of the load of the gripping means and the support structure (in the case of several motion units, the load is divided among the different motion units). Alternatively or additionally, the slider may comprise one or more upper sliding elements in contact with at least one corresponding bearing shoe of the housing element.The sliding elements and / or bearing shoes are preferably maintenance-free and / or free of lubricant, while the sliding elements are preferably maintenance-free guide tracks. Alternatively or additionally, the sliding elements and / or bearing shoes can be adjustable.According to a further embodiment, at least two lifting cables are connected to the housing element. For example, two hoisting ropes may be connected to the housing element forming a triangle, wherein the tip of the triangle points to the moving unit and the base of the triangle is formed by a distance between the rope pulleys mounted on the trolley and guiding the hoisting ropes to the anchor points on the housing element. The cable end can be directly connected to the housing element via cable connections.Furthermore, each lifting cable is pivotably connected to the housing element via a connecting element, wherein the connecting elements of a movement unit are preferably pivotably connected to the housing element about a common axis. These connecting elements serve as hoisting cable compensating beams that allow the micromovement of the attached beam structure (e.g., spreader / sheave cross-frame) without affecting individual hoisting cable loads (i.e., the cable loads remain evenly distributed). Thus, the operating stability of the individual lifting ropes is not impaired by the micromovements.According to a further embodiment, the translation mechanism comprises at least four movement units, wherein each movement unit is connected to at least one lifting cable, while at least two movement units are arranged to move the carrier construction in one of the translation directions (e.g. for the portal displacement) and at least two further movement units are arranged to move the carrier construction in the other translation direction (e.g. for the trolley displacement). The movement units assigned to a respective direction of translation are preferably arranged on mutually opposite sides of the carrier construction.Each pair or group of motion units responsible for micro-motion in one of the translation directions may be driven by a common actuator or each motion unit may have its own actuator. Preferably, two lifting ropes are connected to each of the at least four movement units, which, as already described, form a triangle.According to a further embodiment, the positioning means further comprises a tilt angle detection means for detecting a current tilt angle, in particular a trim angle, of the carrier structure, wherein the tilt angle detection system is connected to the tilt actuator and to the tilt frame and preferably comprises a cable tension transmitter. The body of the cable tension transmitter can be connected to the tilting actuator or a support structure thereof, while the end of the cable tension can be connected to a movable part of the tilting frame, or vice versa.According to a further embodiment, each pivot element is connected to a movement unit such that it can be pivoted about a second pivot axis and is connected to the tilting frame such that it can be pivoted about a third pivot axis, wherein the second and the third pivot axes are parallel to the first pivot axis. The tilting frame is configured to pivot the pivot elements in the same direction (clockwise or counter-clockwise) about the first pivot axes in the case of a movement caused by the tilting actuator.The pivot elements are preferably arranged and / or formed in such a way that, by moving the tilting frame, the pivot elements connected to one of the movement units move the respective movement unit in an upward direction with respect to the tilting frame, while the pivot elements connected to the other movement unit move the respective movement unit in a downward direction with respect to the tilting frame. Since the moving units are held by hoisting ropes and do not move vertically with respect to the trolley, said mechanism results in a rotation of the tilting frame and thus of the support structure connected to the tilting frame about the first tilting axis which is parallel to the first, second and third pivot axes of the pivot elements.The pivot members may have an L-shape, the ends of the short rod of the "L" being pivotally connected to the tilting frame and the ends of the long rod of the "L" being pivotally connected to the respective moving units. The rods of the "L" can form a 90° angle, but angles which are greater or less than 90° are also conceivable. However, other forms of the pivot elements are possible, as a result of which the tilting dynamics effected by the tilting actuator are influenced.According to a further embodiment, the tilting frame comprises two parallel longitudinal beams extending between the moving units, which are connected to the opposite ends of the tilting frame, wherein each longitudinal beam is pivotably connected at each end to two pivoting elements. The longitudinal beams are preferably connected to one another via at least one cross member. When the tilting actuator is activated, the longitudinal beams move along their longitudinal direction, as a result of which the pivot elements connected thereto are pivoted about their first axis.According to a further embodiment, at least two of the at least four movement units are connected to the tilting frame and at least two of the at least four movement units are pivotably connected directly to the carrier structure, i.e. not to the tilting frame.According to a further embodiment, the tilting mechanism is configured to tilt the carrier construction about the first tilting axis and / or about a second tilting axis in a range of ±2° or greater, preferably ±5° or greater. For example, a trim rotation about the first tilt axis could be in a range of ±2.5°, while a rotation about the second tilt axis could be in another range, for example ±5°. These numbers are of course only exemplary and could be different depending on the exact configuration of the positioning means.According to a further embodiment, the lifting device further comprises at least one control device which is designed to receive signals from the one or more displacement detection means and / or the one or more tilt angle detection means, to compare said signals with a known or measured desired position and to control the shift actuator(s) and / or tilt actuator(s) on the basis of said comparison. The desired position can be a desired position of the carrier construction / of the gripping means (e.g. of a spreader or a cable roller cross-piece) and / or a position of a target container. The displacement detection means and / or the tilt angle detection means may cooperate with a detection system (e.g. a sensor system) to acquire the necessary information for suitably controlling the various actuators of the positioning means. This allows precise microcontrollering and positioning of the gripping means with respect to a target container and therefore facilitates automation of the container gripping and transposing process.The micromovements along the translation directions and the rotation of the support structure may be controlled via a common controller or each micromovement may be controlled by a separate controller. The at least one controller may be a variable frequency controller.In one embodiment, the tilting actuator, which may be or include, for example, a motorized linear gear drive, includes a variable frequency control system. This feature provides a smooth ramp for accelerating and decelerating trimming rotation of the support structure. The type of movement is thus considered to be continuously variable, resulting in very accurate positioning of the support structure for a given trim angle. The angle of the beam structure can be measured with a precise onboard measurement / scanning system, which data can be used by a controller, for example a programmable logic controller (PLC) of the crane, to correct the trim angle. The tilt angle detection means preferably comprises a cable encoder which provides an infinite range of trim position measurement values within the operating limits of the assembly. Thus, the support structure can be compensated from each trim angle position using the current measured trim angle transducer positioning.In a further embodiment, the displacement detection means comprises a cable tension transducer providing an infinite range of position measurements between the two outer ends of the associated micro-motion arrangement / motion unit. The shift actuator preferably includes a variable frequency control system. This feature provides a smooth ramp for acceleration and deceleration of the beam construction micromovement along the respective translation direction. The type of linear movement is thus considered to be continuously variable, which leads to a very precise positioning of the support structure in the transverse plane. The target position for the beam construction position can be measured precisely using an on-board scanning system, while the current beam construction position is detected, for example, by using tracking sensors, e.g., crane and spreader position tracking sensors. Using the micromovement cable feeders, the gripping means can be positioned continuously in an exact required position.According to a further embodiment, the container gripping means is a spreader comprising the support structure or a cable roller traverse comprising the support structure and connected to one or more spreaders. The positioning means may be considered a part of the spreader / sheave traverse or a separate element mounted to the spreader / sheave traverse.The gripping mechanism preferably comprises a plurality of corner locks for locking in respective locking elements of a container.According to a further embodiment, the lifting device further comprises a main beam extending horizontally between a lifting structure which can be moved along rails on wheels, for example. The trolley is movably mounted on the main support, i.e. the trolley can move along the main support, for example on rails.Further features, details and advantages of the present invention will become apparent from the embodiments explained below with reference to the figures. The drawings show in: FIG. 1 : shows the container gripping means according to an embodiment of the invention in a perspective view; FIG. 2 : only the positioning means in a perspective view; FIGS. 3-4 show one of the movement units in a perspective view and a side view, respectively; and FIGS. 5-6 show the trolley with the container gripping means in a schematic front and side view, respectively.FIG. 1 shows the container gripping means 10 of a gantry crane (=lifting device) according to a preferred embodiment of the invention in a perspective view. FIGS. 5 and 6 show a front and side view, respectively, of the trolley 1 of the gantry crane together with a schematic illustration of the container gripping means 10. The micromoving elements of the positioning means 20 according to the invention are not shown in FIGS. 5-6, the main focus of these representations instead lies on the hoist rope cutting-in system.The container lift gantry crane comprises a main beam (not shown) to which a trolley 1 is movably connected. The trolley 1 can be moved along the main support, for example on rails. The main beam extends in a perpendicular direction (hereinafter referred to as a Y direction or a Y axis) to a main moving direction of the gantry crane (hereinafter referred to as an X direction or an X axis).A spreader 10 (= container gripping means) is suspended from the trolley 1 by eight hoisting ropes 2 running from hoisting rope jacks 6 via hoisting rope pulleys 7, all attached to the trolley 1, to their respective anchor points on the top of the spreader 10 (see Figs. 5 and 6).At the top of the spreader 10 and lying between the spreader 10 and the anchor points of the hoisting ropes 2 there is a positioning means 20 in the form of a mechanical micromovement arrangement. FIG. 2 shows the detached positioning means 20 according to the embodiment of the invention set forth in FIG. 1.The spreader 10 comprises a support structure 12 (also referred to as spreader frame) and a gripping mechanism 14, wherein the gripping mechanism 14 comprises four corner locks 5 for locking in respective corner lock parts of a container (not shown) in a known manner. The corner locks 5 are located at the four corners of the spreader frame 12.The micro-motion system / positioning means comprises a translation mechanism with four individual motion units 30, 32 (also referred to as micro-motion arrangements) as outlined in Figures 3 and 4, and a tilting mechanism with a trim linkage system as shown in Figure 2. These moving units 30, 32 and the trimming linkage system are fixed to the spreader frame 12. The motion units 30, 32 may be operated from electrical or hydraulic power sources that may move sliders 36 of the motion units 30, 32 to provide the required micro-motion in the X direction (portal displacement) or the Y direction (trolley displacement). The trim linkage system may be operated by an electrical or hydraulic power source that may move the trim linkage, thereby causing the spreader 10 to be trimmed up or down about a defined controlled position.The spreader frame 12 has a substantially rectangular shape when viewed from above. Two of the moving units 30 are responsible for moving the spreader frame 12 along the Y direction and are located at opposite ends along the long axis of the spreader frame 12, the other two moving units 32 are responsible for moving the spreader frame 12 along the X direction and are pivotally connected directly to the spreader frame 12 at the other two sides along the short axis of the spreader frame 12. The moving units 30, 32 move the spreader frame 12 sideways in the XY plane, also referred to as transverse plane, within a range of ±300 mm each. Depending on the configuration of the movement units 30, 32, however, shorter or longer movement ranges are also conceivable.In the embodiment shown, all four movement units 30, 32 have an identical(s) construction / construction. One of the movement units 30 is shown in a perspective view in FIG. 3 and in a side view in FIG. 4.The movement unit 30 comprises a housing element 34, to / on which two lifting ropes 2 are connected / anchored. A bow-shaped slider 36 is movably connected to the housing element 34 and can be displaced relative to the housing element 34 in the respective micro-movement direction. The slide 36 is pivotably connected directly to the spreader frame 12 (in the case of the movement units 32 responsible for the portal displacement along the X direction) or pivotably connected to two pivot elements 52 of the trim linkage system (in the case of the movement units 30 responsible for the trolley displacement along the Y direction).These pivotal connections are made with maintenance free bushes 33 formed in the lower part of the slider 36. Such bushings 33 are resilient in nature so that any deformation of the assembly under load conditions can be accommodated without compromising the integrity of the pin connections.In order to allow the sliding movement of the slider 36 relative to the housing member 34, the slider 36 comprises a number of maintenance-free guide tracks 37 (=slide members) which extend along an elongate part of the slider 36 and have a length as long as the micromovement range of the respective moving units 30, 32 or longer. The housing member 34 includes two half assemblies enclosing the elongate portion of the slider 36 and including adjustable, maintenance free bearing shoes 38. These bearing shoes 38 are in contact with the guide tracks 37, while bearing shoes 39 of the housing member 34 are in contact with respective lower guide tracks 37 at a bottom of the elongate part of the slider 36 and receive the load / weight of the spreader 10.The slider 36 can be moved relative to the housing member 34 by means of a gear drive (=shift actuator), which gear drive comprises a rack 40 connected to a bottom part of the elongated part of the slider 36 and a pinion 42 connected to a drive shaft 44 driven by a motor unit 46 (a motorized gear unit). The housing member 34 includes bearings 45 which support the drive shaft 44 and which are located below the rack 40. Therefore, the pinion is also located below the rack 40. the lower guide tracks 37 are located above the rack 40.The motor unit 46 is fixed to a motor torque arm plate 47 that is attached to the outside of the housing member 34 and extends in an inward direction of the spreader 10. The hoisting rope linkage is connected to the upper side of the housing element 34. By rotating the drive shaft 44 by means of the motor unit 46, the pinion 42 engaging the rack 40 results in linear movement of the slider 36 with respect to the housing member 34, thereby producing the desired micro-movement.The movement unit 30, 32 also comprises a cable tension transducer 48 (=localization detection means) for providing a position feedback. The cable take-off 48 is attached to the slider 36 and the cable end is attached to the housing member 34. The relative position of the slide piece 36 with respect to the housing element 34 can thereby be precisely measured by means of the cable tension transmitter 48, wherein the signal given by the cable tension transmitter 48 is representative of a current position of the spreader 10 relative to the trolley 1 in the respective translation direction.The lifting ropes 2 are connected to the upper part of the housing element 34 by means of two compensating beams 4 (=connecting elements) which are mounted on the housing element 34 such that they can pivot about a common pivot axis. Each lifting cable 2 is anchored to the respective compensating carrier 4 via a lifting cable tension regulator turnbuckle 3.As the input shaft 44 is rotated by the motorized gear box 46, the gear 42 that is operatively connected to the rack 40 rotates. Therefore, the slider 36 moves, resulting in a linear micro motion. This configuration of the gantry crane and trolley displacement micromovement assemblies (moving units 30 and 32) with the hoist cable leveling beams 4 allows the micromovement of the attached spreader frame 12 without affecting individual cable loads (i.e., the cable loads remain evenly distributed). Thus, the operational stability of the individual hoisting ropes 2 is not impaired by the micromovements.The cable transmitter 48 provides an infinite range of position measurements between the two extremities of the micromovement assembly (i.e., between the two maximum positions of the slider 36 relative to the housing member 34). The motorized transmission 46 further includes a variable frequency control system. This feature provides a smooth ramp for accelerating and decelerating the spreader micromovement. The movement is thus considered to be continuously variable, which leads to a very precise positioning of the spreader 10. The target position for the spreader position is accurately measured using an on-board scanning system, while the spreader position is known through the use of crane and spreader positioning tracking sensors. Using the micro-motion cable feeders 48 (in the embodiment shown, each of the motion units 30, 32 or at least each pair of motion units 30, 32 may have its own cable feeder 48), the spreader 10 may be positioned continuously at a precise location required.The construction and technology used in constructing the system of the present invention enables unrestricted operation of the machines without compromising the reliability of the rack and pinion mechanism under the impact of impact loads (as are common in container turnover systems).FIG. 2 outlines the arrangement for the trim linkage system. The linkage comprises a tilting frame 50 with two parallel longitudinal beams 51 extending along the long axis of the spreader 10 and rigidly connected by two cross beams 53 extending along the short axis of the spreader 10. Four pivot members 52 in the form of L-shaped pivot arms are pivotally connected to both ends of each side member 51 of the tilting frame 50. The pivot members 52 are pivotally connected to the beams 51 via the ends of their shorter arms of the "L" so that on either side of the tilting frame 50 the ends of the long arms of the "L" point away from the tilting frame 50.The pivot members 52 are the mechanical links connected to the spreader frame 12 and the trolley displacement micromovement assemblies (moving units 30). The pivot elements 52 are also pivotally connected to the spreader frame 12 about first pivot axes 54 parallel to the direction of movement of the trolley displacement micro-motion assemblies (motion units 30), i.e. parallel to the Y direction. The pivoting bends of the pivoting elements 50 about the first pivot axes 54 are located at the bending point of the "L". The moving units 30 are pivotally connected to the other ends of the pivot members 52 (the ends of the long arms of the "L") via their maintenance-free bushes 33.The tilt frame 50 is movable along the X direction (as shown in FIG. 2 ) via a tilt actuator, which may be either a hydraulic motor or a motorized linear gear drive. Trim position feedback is provided via a cable encoder 58 (=tilt angle detection means) mounted on the motorized linear gear drive and the cable end is mounted on the tilting frame 50. The tilting actuator 56 is preferably connected to the spreader frame 12 such that the tilting frame 50 can be moved relative to the spreader frame 12.The portal displacement micromovement assemblies (movement units 32) are not connected to the trim mechanism / tilt frame 50, but are directly connected to the spreader frame 12.Activation of the motorized linear gear drive moves the tilt frame 50 linearly, causing a set of pivot members 52 on one side of the tilt frame 50 to move in an upward direction, while on the opposite side the pivot members 52 move in a downward direction, with all four pivot members 52 rotating together clockwise or counter-clockwise about the first pivot axes 54. It is this motion that gives the spreader 10 the trim angle, i.e., the angle of rotation about the Y axis.The motorized linear gear drive includes a variable frequency control system. This feature provides a smooth ramp for accelerating and decelerating the spreader trimming motion. The type of movement is thus considered to be continuously variable, resulting in very accurate positioning of the spreader 10 for a given trim angle. The angle of the spreader 10 is measured using a precise on-board measurement / scan system, which data is used by a programmable logic controller (PLC) of the crane to correct the trim angle. The cable generator 58 provides an infinite range of trim position readings within the operating limits of the assembly (i.e., maximum and minimum trim angles). Thus, the spreader 10 can be compensated from each trim angle position using the actual measured trim angle transducer positioning.The construction and technology used in the construction of the trim system allows unrestricted operation of the system without compromising the reliability of the trim mechanism 40, 42 under the effect of shock loads.The hoisting rope shear used in the embodiment shown consists of a single-strand shear with eight ropes (see FIGS. 5 and 6 ). The one shown in Figures 1-2 and 5-6 is rigid in nature because its structure is composed of up to four equal triangles (two hoisting ropes per triangle), preventing transverse and transverse movement of the spreader 10 / container. The cable ends are connected directly to the cable anchor points of the spreader via the cable connections 3. The positioning means 20 according to the invention allows the spreader frame 10 to be precisely positioned using four independent degrees of freedom (linear movements along the X and Y axes (in addition, the spreader 10 can be moved vertically along the z direction by controlling the hoist winch 6) and rotation about the X and Y axes):Portal displacement - Moving the spreader 10 along the direction of its long axis, i.e. along the X axis (e.g. in a range of ±300 mm);Trolley displacement - Moving the spreader 10 along the direction of its short axis, i.e. along the Y direction (e.g. within a range of ±300 mm);Twist - Twist spreader 10 about the X axis (e.g., within a range of ±5°);Trim - Rotate spreader 10 about the Y axis (e.g., within a range of ± 2.5°).The twisting could be performed, for example, by controlling the respective hoist winch 6 or by providing an additional actively driven mechanical twisting mechanism (not shown in the embodiments of Figures 1 to 6).Instead of just one spreader 10 (single system), the positioning means 20 according to the invention could also be mounted on a cable roller traverse, while the cable roller traverse could, for example, carry two spreaders for simultaneously turning over two containers (twin lifting system).The system according to the invention advantageously allows simultaneous movements along four degrees of freedom, while remaining robust under the effect of impact loads without compromising the reliability of the rack and pinion mechanism / tilting mechanism: 1. the positioning means 20 according to the invention allows simultaneous and precise micromovement of the spreader 10 (or the sheave traverse) including portal displacement, trolley displacement, twisting and trimming. 2. the positioning means 20 according to the invention enables very precise and automated placement of a spreader 10 on the spreader 10 using the above-mentioned micromovement system. Thus, in the micromovement system of the present invention, there is no dwell time associated therewith (i.e., the time that it waits until the natural oscillations of the hoist rope system are sufficiently damped to accurately seat the spreader 10). 3. the mechanisms for generating the micromovements of the spreader 10 are designed to be lubricant-free / maintenance-free:portal and trolley displacing mechanism: rack and pinion drive system with moving housings sliding on a lubricant-free sliding system;trim linkage connected to the trolley displacement micromovement mechanisms (moving units 30).4. The configuration of the portal and trolley displacement micromovement arrangements (movement units 30 and 32) with hoist cable compensation beams 4 allows the micromovement of an attached spreader 10 / sheave cross without affecting individual hoist cable loads (i.e. the cable loads remain evenly distributed), so that the operating strength of individual hoist cables 2 is not impaired by the micromovements.The system according to the invention enables improved automation of container cranes and thus leads to increased productivity.List of Reference Numerals1 Trolley 2 Lifting cable 3 Cable connection (lifting cable tension regulator tension lock) 4 Connecting element (compensating carrier) 5 Corner lock 6 Lifting cable winch 7 Lifting cable pulley 10 Container gripping means (spreader / cable pulley cross-piece) 12 Carrier structure (spreader frame / cable pulley cross-piece frame) 14 Gripping mechanism 20 Positioning means 30 Movement unit (Y direction / trolley displacement) 32 Movement unit (X direction / portal displacement) 33 Bushing 34 Housing element 36 Slide piece / linkage element 37 Slide element (guide track) 38 Bearing shoe 39 Support shoe 40 Toothed rack 42 Pinion 44 Drive shaft 45 Drive shaft bearing 46 Motor unit 47 Motor torque arm plate 48 Displacement detection means (cable tension transmitter) 50 Tilting frame 51 Longitudinal carrier 52 Pivot element 53 Cross-piece 54 first pivot axis 56 tilting actuator 58 tilting angle detection means (cable tension transmitter)

Claims

Lifting device for lifting and transposing a container, in particular a gantry crane, comprising a trolley (1) movable in a horizontal direction and a vertically movable container gripping means (10) connected to the trolley (1) via a plurality of lifting ropes (2), wherein the container gripping means (10) comprises a support structure (12) extending along a transverse plane, a gripping mechanism (14) for gripping a container and a positioning means (20) for moving the support structure (12) with respect to the trolley (1), wherein the positioning means (20) comprises a translation mechanism configured for independently moving the support structure with respect to the trolley (1) along two orthogonal translation directions (X, Y) in the transverse plane and a tilting mechanism, which is designed for tilting the carrier structure (12) with respect to the trolley (1) about at least one first tilting axis, wherein the translation mechanism comprises at least one actively driven movement unit (30, 32), which is connected to the carrier structure (12) and to which at least one lifting cable (2) is attached, for moving the carrier structure (12) with respect to the trolley (1) along one of the translation directions (X, Y), while the movement unit (30, 32) is preferably pivotably connected to the carrier structure (12), and wherein the pivot axis is parallel to the transverse plane and / or parallel to the respective translation direction, characterized in that the tilting mechanism comprises a tilting frame (50) and the translation mechanism comprises at least two movement units (30), which are connected via pivot elements (52) to opposite ends of the tilting frame (52), wherein each pivot element (52) is pivotably connected to the carrier structure (12) about a first pivot axis (54) which is parallel to the first pivot axis, while the tilt frame (50) is movable with respect to the carrier structure (12) by means of a tilt actuator (56), in particular a hydraulic cylinder or a motor unit, wherein the motor unit preferably comprises a hydraulic or electric motor and / or a transmission.Lifting device according to claim 1, wherein the tilting mechanism is configured to tilt the support structure (12) with respect to the trolley (1) about a second tilting axis that is orthogonal to the first tilting axis, wherein the first and the second tilting axes are preferably parallel to the transverse plane and / or to the translation directions (X, Y).The lifting device according to claim 1 or 2, wherein the movement unit (30, 32) comprises a housing element (34) to which the at least one lifting cable (2) is connected, and comprises a linkage element (36) connected to the carrier structure (12), while the linkage element (36) is movably coupled, preferably slidably coupled, to the housing element (34).Lifting device according to claim 3, wherein the slide piece (36) is movable with respect to the housing element (34) by means of a shift actuator, in particular a hydraulic cylinder or a toothed gearing, preferably in a range of greater than or equal to ± 100 mm, further preferably of ± 200 mm or more, most preferably of ± 300 mm or more.The lifting device according to claim 4, wherein the moving unit (30, 32) comprises a gear drive for moving the slide (36) with respect to the housing element (34), wherein the gear drive comprises a rack (40) connected to the slide (36) and a pinion (42) arranged on or in the housing element (34) and meshing with the rack (40), while the pinion (42) is connected to a drive shaft (44) that can be driven by means of a motor unit (46), wherein the motor unit (46) preferably comprises a hydraulic or electric motor and / or a gear.Lifting device according to claim 4 or 5, further comprising a displacement detection means (48) for detecting a current relative position of the carrier construction (12), while the displacement detection means (48) is preferably arranged on a movement unit (30, 32), in particular is connected to the housing element (34) or shift actuator and to the slide piece (36) of a movement unit (30, 32), and preferably comprises a cable tension transmitter (58).Lifting device according to any one of claims 3 to 6, wherein the slider (36) comprises at least one sliding element (37), in particular a guide track, extending along the slider (36) in the direction of movement and being in contact with at least one bearing shoe (38, 39) of the housing element (34), while the slider (36) preferably comprises at least two lateral sliding elements (37) arranged on opposite sides, each in contact with at least one lateral bearing shoe (38) of the housing element (34), and at least one lower sliding element (37) arranged on an underside of the slider (36) and in contact with at least one support shoe (39) of the housing element (34).Lifting device according to one of claims 3 to 7, wherein at least two lifting ropes (2) are connected to the housing element (34), wherein each lifting rope (2) is pivotably connected to the housing element (34) via a connecting element (4), while the connecting elements (4) are preferably pivotable about a common axis.Lifting device according to any one of the preceding claims, wherein the translation mechanism comprises at least four movement units (30, 32), each movement unit (30, 32) being connected to at least one lifting cable (2), while at least two movement units (30) are arranged to move the support structure (12) in one of the translation directions (Y), and at least two further movement units (32) are arranged to move the support structure (12) in the other translation direction (Y), while the movement units (30, 32) associated with a respective translation direction (X, Y) are preferably arranged on mutually opposite sides of the support structure (30, 32).Lifting device according to one of the preceding claims, wherein the positioning means (20) further comprises a tilt angle detection means (58) for detecting a current tilt angle, in particular a trimming angle, of the carrier structure (12), wherein the tilt angle detection means (58) is connected to the tilt actuator (56) and to the tilt frame (50) and preferably comprises a cable tension transmitter.The lifting device according to any one of the preceding claims, wherein each pivot element (52) is connected to a movement unit (30) such that it can pivot about a second pivot axis and is connected to the tilting frame (50) such that it can pivot about a third pivot axis, wherein the second and the third pivot axis are parallel to the first pivot axis (54), while the tilting frame (50) is configured to pivot the pivot elements (52) about the first pivot axes (54) via a movement in the same direction caused by the tilting actuator (56), and while the pivot elements (52) are preferably arranged and / or configured such that, by moving the tilting frame (50), the pivot elements (52) connected to one of the movement units (30) move the respective movement unit (30) in an upward direction with respect to the tilting frame (50), while the pivot elements (52) connected to the other movement unit (30) move the respective movement unit (30) in a downward direction with respect to the tilting frame (50).Lifting device according to any one of the preceding claims, wherein the tilting frame (50) comprises two parallel longitudinal beams (51) extending between the moving units (30), each longitudinal beam (51) being pivotably connected at each end to two pivoting elements (52), while the longitudinal beams (51) are preferably connected to each other via at least one cross beam (53).The lifting device according to any one of the preceding claims, wherein at least two moving units (30) of the at least four moving units (30, 32) are connected to the tilting frame (50) and at least two moving units (32) of the at least four moving units (30, 32) are pivotably connected directly to the support structure (12).The lifting device according to any one of the preceding claims, wherein the tilting mechanism is configured to tilt the support structure (12) about the first tilting axis and / or about a second tilting axis in a range of ± 2° or greater, preferably ± 5° or greater.Lifting device according to claim 6 and / or claim 10, further comprising at least one control device, in particular a variable frequency control device, configured to receive signals from the displacement detection means (48) and / or the tilt angle detection means (58) for comparing said signals with a target position and for controlling the shift actuator and / or tilt actuator (56) on the basis of said comparison.The lifting device according to any one of the preceding claims, wherein the container gripping means (10) is a spreader or a cable pulley cross-piece connected to one or more spreaders.

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