| 摘要 |
A tapping machine has a base plate fixed to one of the platens, a spindle extending along a spindle axis between the platens in the closing direction of the press actuating the machine, and a nut threaded on the spindle. The nut is normally rotatable about the spindle axis on the base plate and the spindle is fixed nonrotatably about the spindle axis on the other platen so that relative displacement of the platens rotates the nut in the base plate. An element displaceable on the base plate along an element axis but nonrotatable on the base plate about the element axis carries a plurality of tap holders generally fixed relative to the element axis in the element and rotatable in the element about respective tap axes parallel to the element axis. Respective taps are fixed axially and rotationally in the holders. A rotary transmission is provided that operatively connects the rotary nut and the holders for synchronously rotating the holders and their taps at a predetermined tap rotation rate about the tap axes on rotation of the nut about the spindle axis. An addition an axial-feed transmission connects the rotary nut and the element for synchronously axially advancing the element with the taps and tap holders on displacement of the platens from the outer position to the inner position through a predetermined tap stroke equal to a fraction of the press stroke and at a rate such that the taps are rotated through substantially only one revolution while being advanced through a distance equal to the pitch. |
