Monitoring apparatus and control method of crane hoisting vertical deviation angle

An apparatus for monitoring a hoisting verticality deviation angle of a crane, comprising:

• a measuring platform fixed on outside of a guard plate of a movable pulley of a lifting pulley block of the crane, said measuring platform satisfying the requirement that its surface is horizontal when the hoisting verticality deviation angle is 0 degree;
• a dual-axis inclinometer, fixed on the surface of the measuring platform, measuring an angularity of the surface of the measuring platform relative to a horizontal plane to obtain the hoisting verticality deviation angle;
• a wireless transmitter, also fixed on the outside of the guard plate of the movable pulley of the lifting pulley block of the crane, to transmit dual-axis verticality deviation angle signals representing dual-axis verticality deviation angles generated by the dual-axis inclinometer;
• a wireless receiver enclosed in a cab of the crane to receive said dual-axis verticality deviation angle signals;
• a control display, also enclosed in the cab of the crane, used to process said dual-axis verticality deviation angle signals into the hoisting verticality deviation angle and display said hoisting verticality deviation angle.