Patent ID: 6050186
Filing Date: 2000-04-18
Classification: B41F

Abstract:
A dampening mechanism for use in offset lithography, comprising:(a) sprayer means for producing a spray of dampening water, the spray being of such cross sectional shape as to differ in dimensions in two orthogonal directions;(b) sprayer rotating means for rotating the sprayer means in order to cause angular displacement of the spray about an axis passing through the geometric center of the cross section of the spray; and(c) baffle means defining an aperture through which the spray travels, the aperture having a width shorter than the longer dimension of the cross section of the spray and longer than the shorter dimension of the cross section of the spray, both cross sectional dimensions of the spray under comparison being measured in a plane containing the aperture;(d) whereby the supply rate of dampening water that is allowed through the aperture is infinitely variable by changing the angular position of the spray relative to the aperture between a minimum dampening position where the spray has opposite longitudinal end portions of its cross section interrupted to the utmost by the baffle means and a maximum dampening position where the spray is allowed wholly through the aperture.