JPH02149689U - - Google Patents

Description

[Brief explanation of drawings]

Fig. 1 is a side view of an embodiment of the present invention, Fig. 2 is a circuit diagram of an arithmetic circuit in an embodiment of the invention, and Fig. 3 is a hydraulic circuit diagram of a winch for jib hoisting in an embodiment of the invention. , FIG. 4 is a diagram showing the relationship between the jib length, hoist rope length, and jib angle in one embodiment of the present invention, FIG. 5 is a flowchart of the arithmetic circuit, and FIGS. 6 and 7 are diagrams of the conventional telescopic FIG. 2 is a side view of a mobile crane equipped with a jib according to the present invention. In the figure, 1 is a telescopic jib, 2 is a traveling body, 3 is a swivel base, 11 is a wire rope for hoisting, 12 is a winch for jib hoisting, 18 is a jib length detector, 19 is a jib length detection signal, and 20 is a jib length detection signal. Controller, 21 is a jib angle detector, 22 is a jib angle detection signal, 23 is a wire rope payout length detector, 24 is a wire rope payout length detection signal, 25 is a central processing unit, 26 is a data storage device, 27 1 is a read-only memory, 28 is an arithmetic circuit, 29 is a data signal of the appropriate hoist rope length, 31 is a directional control valve, 3
4 is a hydraulic pump, 35 and 36 are piping lines of a hydraulic circuit for a jib hoisting winch, 37 is a drum, and 38 is a hydraulic motor.

Claims (1)

[Claims for Utility Model Registration] A mobile crane consisting of a swivel base provided on the upper surface of a traveling body and a telescopic telescopic jib supported on the swivel base so as to be able to rotate in a vertical plane. 1. A mobile crane, characterized in that a jib hoisting winch for paying out and winding up a wire rope is provided on the swivel base, and the hoisting wire rope is connected to a tip of a telescopic jib. 2. A jib length detector that detects the length of the telescopic jib, a jib angle detector that detects the angle of the jib, a wire rope unwinding length detector that detects the unwinding length of the hoisting wire rope, and a telescopic jib When changing the length of the jib, the direction of the hydraulic circuit of the jib hoisting winch is changed so that the angle of the telescopic jib is kept constant by comparing and calculating the detection signals output by each of the above-mentioned detectors with the data signals stored in advance. The mobile crane according to claim 1, further comprising an arithmetic circuit for controlling the valve.