GB1013923A - Xerographic member charging method and apparatus - Google Patents

Abstract

1, 013, 923. Apparatus for charging electrophotographic surfaces. RANK-XEROX Ltd. Nov. 28, 1961 [Dec. 9, 1960], No. 42560/61. Heading G2H. A xerographic member is charged by passing across its surface in contact therewith a plurality of electronically conductive electrodes. In Figs. 1 and 2 a xerographic plate 11 held by clips 17 on a movable base plate 12 is charged through a number of spaced fine wires 20 clamped between bars 21 which are connected to a potential source 42 but electrically connected to the bars only by a layer of resistive material 22, so that if one wire is temporarily grounded little effect would be produced on the adjacent wires. The wires may be of stainless steel, phosphor bronze, foil, metallized plastic sheet suitably slit and the wires may be woven into a fabric of insulating strands which maintain the spacing between the wires (Fig. 6 not shown). It is explained that the charge pattern formed on the plate is in the form of a series of strips which may correspond to half tone rendering, but, by arranging the wires slantwise or in layers a more uniform charge may be applied to the plate (Fig. 11, 12 and 13 not shown). The clamping arrangement may be pivoted within a holder and means may be provided for moving the charging wires away from the plate and into the holder (Fig. 9 not shown). Alternatively, where the plate to be charged is on a drum, the wires may be stretched between two supports so that they touch the surface tangentially (Fig. 7 not shown) or they may be formed by winding a wire helically around a channel shaped holder and cutting the wires along the rear side of the holder (Fig. 8 not shown). In Fig. 10 the wires are secured on a drum coated with high resistance material and located within a shield, the drum being rotatable so that the wires may be cleaned by a pad 48 inside the shield. Specification 1,013,924 is referred to.