| 摘要 |
PURPOSE:To enhance the indexing accuracy, the flatness and rigidity of the table surface by setting the meshing force of steel balls for indexing and the cramping force of an indexing table individually at respective optimum sizes, and thereby preventing application of unreasonable force to these balls and table. CONSTITUTION:Fluid pressure is supplied to a lower cylinder chamber 81, and if a piston 7 and an indexing table 5 are lifted, an indexing member 2 coupled by a lief spring 12 rises to cause disengagement of the steel balls 1. When under this condition a rack 9 is moved force and aft and a piston rod 71 is rotated by turning a pinion 10, and if the supply of fluid pressure is switched to an upper cylinder chamber 82, the piston 7 and indexing table 5 will sink. Consequently, the indexing member 2 is sunk by the lief spring 12, and steel balls 1 engage with each other to provide indexing. When the undersurface of the indexing table 5 comes in contact with the oversurface of a pressure receiving plate 11 and the surface pressure of the contact surfaces attains a certain specific level, the indexing table 5 is cramped by the specified force. |
