Patent ID: 6351720
Filing Date: 2002-02-26
Classification: B66C,G01B

Abstract:
A trolley camera position detecting apparatus characterized by a crane comprising a trolley moving on a girder, a trolley camera mounted at the trolley, a leg supporting the girder and wheels for allowing the crane to travel on a rail,wherein a leg target is provided to travel together with the crane in a position away from a center of the rail by a predetermined distance, a girder camera is mounted on said girder, the girder camera provided with a clinometer to thereby allow measuring an inclination &thgr;cg between a camera centerline and said leg target using the girder camera and measuring an inclination &thgr;kg using the clinometer, an initial value &dgr;go of a horizontal travel amount &dgr;g of a girder reference point in relation to the center of the rail is measured in advance using an instrumentation, and a constant value &dgr;o in regard of the horizontal travel amount is calculated using initial values &thgr;cg and &thgr;kgo of the inclinations &thgr;cg and &thgr;kg, respectively at a time of measuring the initial value of &thgr;go as indicated by â€ƒ&dgr;o=&dgr;goâˆ’Hg(&thgr;cgoâˆ’&thgr;kgo)where Hg is a height from the leg target to the girder camera, said inclinations &thgr;cg and &thgr;kg are calculated in time sequence during loading, a change of the horizontal travel amount &dgr;g from said reference point on said girder is calculated using the obtained &thgr;cg, &thgr;kg and the constant value &dgr;o as indicated by&dgr;g=&dgr;oâˆ’Hg(&thgr;cgâˆ’&thgr;kg), a position of said trolley camera with reference to the center of the rail using the horizontal travel amount &dgr;g, and structural elements are provided for carrying out the mathematical expressions for calculating the constant value &dgr;o in regard of the horizontal travel amount and the horizontal travel amount &dgr;g.