| 摘要 |
PROBLEM TO BE SOLVED: To provide a guide mechanism, which is used for an electronic component mounting head, is low in a slide resistance and has not a looseness. SOLUTION: A guide mechanism is constituted in such a structure that the guide mechanism has a sleeve having a through hole with the polygonal section and a shaft which is inserted in the through hole. The outer surface of the shaft is formed into a prismatic shape with the section formed into a polygon similar to the through hole and is a little smaller than the through hole provided in the sleeve and a gap is formed between each surface of the prism-shaped outer surfaces of the shaft and the through hole. A needle rolling-bearing comprising a plurality of needles, which are rotatably held by a retainer and are juxtaposed to each other in the axial direction, is inserted in each of the gaps and the shaft is movably provided at a slight stroke in the axial direction in the sleeve. The above-mentioned polygon is favorably a quadrangle or a hexagon. |
