A securing method for securing a crane on the occurrence of an exceptional event, the crane including a control-command system connected to actuators of the crane and integrated within a processing unit of the crane, the processing unit connected to movement, load and safety sensors placed on elements of the crane and configured to deliver information from events representative of exceptional events, wherein the securing method includes establishing a list of exceptional events detectable by the movement, load and safety sensors, associating levels of severity to each exceptional event, evaluating the level of severity of a detected exceptional event based on corresponding event information, switching from a nominal operating mode to a secure operating mode by applying a safety instruction associated with a severity level for the detected exceptional event, and emitting an alert message informing of the occurrence of the exception event.

The present disclosure relates to an apparatus and to a method for controlling a crane slewing gear. The apparatus comprises a hydraulic motor for driving the slewing gear and for braking the slewing gear from a rotational movement. The slewing gear is kept stationary via a holding brake. A hydraulic brake circuit for controlling the holding brake, a load sensing device for measuring a load instantaneously taken up by the crane, and an orientation sensing device for measuring an instantaneous orientation of the crane and/or of at least one crane component are furthermore provided. In accordance with the disclosure, a hydraulic limitation circuit is provided by means of which a hydraulic pressure applied to the motor can be limited to a specific limit value. A control unit is furthermore provided that determines a maximum permitted torque and/or a parameter derived therefrom for a current slewing gear movement.

A work state monitoring device for a work vehicle is provided, such that an operator can perform the work without receiving a warning. The work state monitoring device acquires a current work state of a crane using work posture detectors. A calculator calculates at least a predetermined work state corresponding to a warning load factor based on the current work state acquired by the work posture detectors. A monitor informs an operator of the predetermined work state calculated by the calculator.

Various hoisting systems with anti-two-block sensing devices are provided. In one embodiment, an apparatus includes a crane having a hoisting line and an anti-two-block sensing device installed about the hoisting line. The anti-two-block sensing device includes an upper chandelier, a lower trigger assembly suspended from the upper chandelier, and a detector positioned to detect movement of the lower trigger assembly with respect to the upper chandelier. The lower trigger assembly can include two plates each having a hoisting line aperture and a slot that allows transverse installation of the plate about the hoisting line. Further, the two plates can be positioned such that their slots are offset from one another and the plates cooperate to fully surround the hoisting line. Additional systems, devices, and methods are also disclosed.

Various hoisting systems with anti-two-block sensing devices are provided. In one embodiment, an apparatus includes a hoisting system having a hoisting line, a sleeve positioned on the hoisting line, and an anti-two-block sensing device installed about the hoisting line so as to allow the hoisting line to move through the anti-two-block sensing device. The anti-two-block sensing device includes a detector positioned to detect a sleeve component when the sleeve is present within the anti-two-block sensing device. Additional systems, devices, and methods are also disclosed.

A full-time anti-sway control method of a bridge crane system based on an inverter structure includes steps of: receiving a specified high frequency and a frequency change time, calculating a time setting range according to a plurality of system parameters and a rope length information of the bridge crane system, selecting a time setting value within the time setting range, dividing the frequency change time into a plurality of time intervals according to the time setting value, adjusting an operation frequency command to change between a low frequency and the specified high frequency within the plurality of time intervals to generate a frequency change curve, calculating a frequency correction amount according to the frequency change curve and the rope length information, and superimposing the frequency change curve and the frequency correction amount to generate an anti-sway frequency command to drive the at least one motor.

A method for moving a load with a crane in a collision-free manner in a space having at least one obstacle includes providing a position of the obstacle, providing at least one safe state variable of the load, determining from the safe state variable a safety zone surrounding the load, and dynamically monitoring the safety zone in relation to the position of the obstacle.

A method for controlling a crane having a boom operating in a circular work area and at least one anti-collision system detecting a risk of collision on a right side and a left side of the boom may be used to direct the boom from a starting angular sector, where a risk of collision with an obstacle has been detected, towards a final angular sector where a risk of interference is low or even zero, based on an interference mapping segmenting the circular work area into several angular sectors and associating with each of them an interference counter value representative of a level of risk of interference. The values may evolve in real time according to the orientations of the boom and collision risk detections.

A method of positioning a movable structure of an overhead crane, the movable structure being either a trolley or a bridge of the overhead crane, the method comprising providing a position reference for the movable structure, controlling with a state-feedback controller the position of the movable structure, the position of the movable structure and a sway angle of the load being state variables of the system used in the state-feedback controller. Further the method comprises determining the position or speed of the movable structure and the sway angle of the load or angular velocity of the load, providing the determined position or speed of the movable structure, the determined sway angle of the load or angular velocity of the load and the output of the state-feedback controller to an observer, producing with the observer at least two estimated state variables, forming a feedback vector from the estimated state variables or from the estimated state variables together with determined state variables, using the formed feedback vector as a feedback for the state-feedback controller, and providing the output of the controller to a frequency converter.

Tower crane (1) comprising a tower (2) on which a rotating portion (3) is pivotally mounted and configurable between a service configuration in which the rotating portion can be rotatably driven by means of a motorized orientation system (40), and an out of service configuration in which the rotating portion is rotatably released to be able to be oriented in the direction of the wind, where a control/command unit (5) activates a monitoring mode in the out of service configuration to detect, depending on variations in the angle of orientation or the angular speed of the rotating portion, if the rotating portion is in one of the following instability states: an autorotation state corresponding to a rotary movement of the rotating portion in a given direction over at least one complete turn; or an oscillation state corresponding to a back and forth movement of the rotating portion about the orientation axis.