Improvement in and relating to grinding machines.

摘要

In computer-controlled adjustment of grinding machine settings, one single ball screw (8) is operative to move a lower table (5) and an upper table (6), mutually locked together, to a terminal position in which locking engagement is released and the direction of table movement reversed. The tables move together from their starting position, as a result of the friction acting there between, to a predetermined upper-table position in which an engagement means (25a) engages and holds the upper table (6). The lower table (5) then continues to move to a position in which reference points located on the tables are spaced at a predetermined distance apart. The tables are then reconnected mechanically by means of the locking device. This procedure enables the entire grinding cycle to be computer-controlled, including the machine-setup operation. The device which locks the tables together comprises excentric shafts (31) journaled in the upper table and provided with locking shoulders (35) which engage or grip an elongated straight edge mounted on the lower table on mutually opposite sides of the straight edge. Oblique forces liable to jeopardize grinding accuracy can therewith be avoided. The invention also relates to a computer-controlled grinding machine provided with a work head and a center-point tailstock (16, 17) operating in the manner stated.