| 摘要 |
<p>A wave isolator (18) is provided for large format drafting plotters (10) for preventing waves in the drafting medium (16) from traveling up the platen (14) and adversely affecting the pen (20) and its operation and reducing acceleration related vertical scalloping of angled lines. Such waves in the medium are generated by the motion of the paper during the plotting operation. The wave isolator comprises at least one strip (22a) of flexible material secured to the platen and of substantially the same length. Preferably, a polyimide film is used, having a coating of a thermoset acrylic resin with additives including conductive carbon black and polyethylene. In operation, when the medium is moving upward, the wave isolator deflects under the increased inertial load, and air trapped between the medium and the platen exits at the sides of the medium, dissipating some of its energy. When the medium is moving downward, the wave isolator sees a negative change in load and responds by flexing upward, tending to increase the volume of air between the medium and the platen, creating a low pressure area which sucks air in at the sides of the medium, again dissipating its energy. Use of the wave isolator of the invention permits high speed, high acceleration plotting on both sheet and roll media without the aid of firmware solutions.</p> |
