| 主权项 |
1. A cutting apparatus, comprising:
an elongate straight blade,
having a forward facing, left-to-right horizontal cutting edge;
the horizontal cutting edge lying in a vertical first plane; a circular blade having a circular cutting edge rotatable in a second plane; and having an axis of rotation perpendicular to the second plane;
the axis moveable from left to right and back in a vertical third plane parallel to the first plane;the third plane being a first horizontal distance forwardly from the first plane;the circular cutting edge having a radius greater than the first horizontal distance;the second plane intersecting the horizontal cutting edge at an angle in the first plane;the horizontal cutting edge having a first point along it which coincides with a second point on the circular cutting edge, at which point sheet material is sheared; and a means for rotating the circular blade about the axis to produce a tangential speed of the circular cutting edge and a linear speed of the axis in the third plane;
the motion of the first point relative to the second point in the left-right direction being within about 3% of the linear speed of the axis in the third plane. |
