Patent ID: 7066704

Claim:
A cart for changing a component supply unit, which component supply unit is connectible with and separable from a component mounting apparatus for a purpose of simultaneously changing a plurality of supplying devices attached to the component supply unit by installing the component supply unit onto the component mounting apparatus or removing the component supply unit from the component mounting apparatus, comprising: a base frame having wheels including caster wheels; lifters fixed to said base frame; a driver, accommodated inside said base frame, for simultaneously driving said lifters, said driver including a hydraulic jack and a lever mechanism, said lever mechanism including (i) a first lever for changing extending and retracting movements of said hydraulic jack into circular movements, (ii) a shaft fixing said first lever in a rotatable manner about an axis of said shaft, and (iii) second levers for simultaneously lifting or lowering said lifters, with one end of each of said second levers being fixed to a corresponding end of said shaft so as to be rotatable about the axis of said shaft; and a holder, fixed to said lifters, for holding the component supply unit, wherein the cart has a multi purpose utility space beneath the component supply unit when held by said holder, said multi purpose space being surrounded by said base frame and said lifters, wherein each of said lifters comprises an elevating rod to be driven by said driver for performing lifting and lowering movements, and a supporting frame having a linear bearing structure for movably supporting said elevating rod in up and down directions, and wherein said linear bearing structure comprises: (i) first engaging elements on an outer surface of said elevating rod along a first direction parallel to the up and down directions of said elevating rod, said first engaging elements including one first engaging element on one side of said outer surface and another first engaging element on a second side of said outer surface, with said one side and said second side opposing one another in a second direction perpendicular to said first direction; and (ii) second engaging elements, on circumferences of at least three guide rollers rotatably fixed to said supporting frame, for holding said elevating rod from opposing sides along said second direction, such that when said first engaging elements engage said second engaging elements, said at least three guide rollers guide a movement of said elevating rod along said first direction while restricting movement of said elevating rod along said second direction and also restricting movement of said elevating rod along a third direction perpendicular to both said first and second directions.