Earthquake resistant crane

A crane comprising;

• girders;
• rail means for supporting the girders;
• a travelling device for moving said girders along the rail means including a plurality of wheels for supporting the girders on the rail means;
• means for mounting each of said wheels on the girders so as enable the wheels to be horizontally displaceable with respect to the girders including vibration direction converting means for resiliently supporting said girders and for converting vertical vibrations to a horizontal displacement of the wheels, said vibration direction converting means comprises a plurality of pairs of cranks, cranks of each pair being pivotally connected at one end thereof to one pair of saddles secured to an undersurface of either end portion of each of said girders, each crank of each pair supporting at the other end thereof a bearing box containing therein a bearing supporting an axle for said wheels, spring means secured at an upper end to each of said girders and at a lower end to a side plate, and means for preventing said spring means from being displaced in a horizontal direction, said slide plate being forced against said bearing box;
• and
• drive control means for driving said travelling device for movement and for interrupting the movement thereof.

An earthquake resistant crane comprising;

• girders;
• rail means for supporting the girders;
• a travelling device for moving said girders along the rail means including a plurality of wheels for supporting the girders on the rail means;
• means for mounting each of said wheels on the girders so as to enable the wheels to be horizontally displaceable with respect to the girders including vibration direction converting means for resiliently supporting said girders and for converting vertical vibrations to a horizontal displacement of the wheels, said vibration direction converting means comprises a pair of trucks, each truck being fitted at a fitting portion for vertical movement to one of a pair of saddles secured to an undersurface of either end portion of one of said girders and supporting at a forward end of each of a pair of horizontal arms a bearing for said wheels for movement in the horizontal direction, a pair of cranks, each crank including a substantially U-shaped arm and a pair of horizontal crank arms, said U-shaped arm including a central portion and two vertically extending portions, the U-shaped arm is pivotally supported at the central portion thereof by one of said saddles and pivotally supported at upper ends of the vertical portions thereof to an associated one of said trucks, a forward end of each of said horizontal crank arms is connected to a bearing box for said bearing so as to convert vertical vibrations to horizontal displacement of the wheels, and spring means mounted between each of said trucks and each of said girders for supporting said girders in a vertical direction;
• and
• drive control means for driving said traveling device for movement and for interrupting the movement thereof.