Patent ID: 7921986

Claim:
A hoisting and lowering driving engagement multi-row chain, each row of the chain comprising: at least two inner link units, each inner link unit including a right and left inner tooth plate arranged in parallel with a front and a rear bush press-fitted between the inner tooth plates in the chain width direction, wherein each of the inner tooth plates has a hook portion and a front and a rear pin hole, where the front and the rear bushes are press-fitted into the front and rear pin hole, respectively; at least two intermediate tooth plates, each intermediate tooth plate having a hook portion and a front and a rear pin hole; at least two outer tooth plates, each having a hook portion and a front and a rear pin hole; and connecting pins which are fitted into the front and rear pin holes of the right and left inner tooth plate, intermediate tooth plates, and outer tooth plates, so that the intermediate tooth plates are disposed in parallel between adjacent inner link units and the outer tooth plates are disposed on the outermost sides of the chain in the chain width direction, wherein the hook portions of the right and left inner tooth plate, intermediate tooth plates, and outer tooth plates are configured to engage with the right and left inner tooth plate, intermediate tooth plates, and outer tooth plates of an opposing row of the multi-row chain when being raised and lowered in the vertical direction when a pair of hoisting and lowering sprockets engages with the bushes, so that the opposing rows of the multi-row chain are integrally raised and lowered and then become disengaged when the opposing rows are moved from the vertical direction to the horizontal direction by the hoisting and lowering sprockets, wherein the right and left inner tooth plate, intermediate tooth plates, and outer tooth plates are all formed of the same material using the same mold in the same orientation, so as to have the same shape, and wherein at least one plate of the right and left inner tooth plate, intermediate tooth plates, and outer tooth plates has a reverse configuration than the remaining plates so that the hook portion of the at least one plate extends in the opposite direction than the hook portion of the remaining plates.