Drive device, apparatus for notching, and method for driving apparatus for notching

Apparatus for notching, comprising:

• a frame with a stand and a headpiece;
• a plunger coupled to the headpiece and movable along a punching axis oriented along a y axis;
• an electrical direct drive for driving the plunger, wherein the direct drive comprises an electric machine with a drive shaft, wherein the drive shaft carries an eccentric, wherein the eccentric is coupled to a connecting rod via a bearing for the connecting rod, and wherein the connecting rod is coupled to the plunger;
• and
• a controller configured to provide an electric control signal for effecting rotation of the drive shaft of the direct drive, in order to effect linear motion of the plunger, characterized in that the rotation of the drive shaft comprises, for realizing a pendular operation of the plunger, a step of rotating forward the drive shaft and a step of rotating backward the drive shaft, wherein when rotating forward and when rotating backward, a punching stroke for punching a notch each is performed,
• wherein in the step of rotating forward, the drive shaft is rotated about a first portion of a full revolution in a first rotational direction to move the plunger from a top reversal point via a lowest reversal point back to the top reversal point,
• wherein in the step of rotating backward, the drive shaft is rotated about the first portion in a second rotational direction opposite to the first rotational direction to move the plunger from the top reversal point via the lowest reversal point back to the top reversal point,
• wherein in rotation of the draft shaft, following completion of a punching process, the drive shaft is rotated to a predetermined rest position starting from a current position, in order to effect an upstroke of the plunger, in order to enable supplying or removing a workpiece to be machined.