Crane safety control system and method, moment limiter and crane

Abstract

The invention discloses a crane, a moment limiter and a safety control system and method. The system comprises a receiving unit and a controller. The receiving unit is used for receiving the pressure difference between pressure oil at an inlet of a hydraulic motor for lifting a winch and the pressure oil at an outlet of the hydraulic motor of a lifting winch and the distance between a fixed pulley set and a movable pulley set of a jib lubbing mechanism. The controller is used for calculating the sling load of the crane according to the pressure difference between the pressure oil at the inlet of the hydraulic motor and the pressure oil at the outlet of the hydraulic motor, calculating the working range of the crane according to the distance between the fixed pulley set and the movable pulley set of the jib lubbing mechanism and comparing the sling load, obtained through calculation, of the crane and the working range, obtained through calculation, of the crane with a preset lifting performance table, so that it is ensured the crane is made to conduct hoisting only in the safety direction through restraint under the condition that hoisting of the crane is not safe. According to the crane, the moment limiter and the safety control system and method, the sling load of the crane is calculated according to the pressure difference between the pressure oil at the inlet of the hydraulic motor and the pressure oil at the outlet of the hydraulic motor, the working range of the crane is calculated according to the distance between the fixed pulley set and the movable pulley set of the jib lubbing mechanism, no coupling relationship exits between calculation of the sling load and calculation of the range, and thus the sling load and the range are independent of each other, and calculation is convenient.

Description

technical field [0001] The invention relates to engineering machinery, in particular to a crane safety control system and method, a moment limiter and a crane. Background technique [0002] In order to ensure the safe operation of large construction machinery such as cranes, the moment limiting unit is an essential component of similar construction machinery. In the prior art, the torque limiting unit generally includes a sensor, a display, and a controller such as a single-chip microcomputer and the like. The sensor can transmit the collected signal to the controller to analyze the current operating state of the crane, and compare it with the lifting performance table stored in the moment limiting unit and the upper and lower limits of the boom angle to determine whether the working state of the crane is safe. If it is safe, the hoisting operation can be continued. Once it is found to be unsafe, the control signal can be triggered to give an audible and visual alarm, and t...

AI Technical Summary

Problems solved by technology

In this technology, the calculation of the hoisting weight of the crane and the calculation of the working range are coupled with each other, and the correlation is too complicated, which requires high performance of the controller.

In addition, the existing technology requires several tension sensors, and the measured value of the tension sensor will be pulled left or right due to eccentric load, side load, leeward, windward, etc., or the installation accuracy and assembly deviation of its own parts. The plate force is not completely within the variable amplitude plane assumed by the calculation model, which will also bring certain calculation errors

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