MAGNETIC PICK-OFF AND RELEASE DEVICE
Original Publication Date: 1984-Oct-31
Included in the Prior Art Database: 2004-Apr-04
Xerox Disclosure Journal
In the development system of an electrophotographic printing machine, a developer roller transports developer material closely adjacent to a latent image recorded on a photoconductive surface. After the latent image has attracted a portion of the developer material thereto, it is desirable for the developer material to fall freely, under the influence of gravity, from the developer roller so as to be mixed with the remaining developer material in the housing. As shown in the drawing, developer roller 10 includes a tubular sleeve 12 having a magnetic member 14 disposed interiorly thereof. Magnetic member 14 is stationary with tubular member 10 rotating in the direction of arrow 16. Magnetic member 14 includes a soft iron keeper 18 having magnets 20 and 22 mounted therein. h4agnets 20 and 22 are of opposite polarity and set side by side in the soft iron keeper 18. Iron keeper 18 forms in region 24 for attracting the developer material to tubular member 12 and an extremely low radial magnetic force in region 26 for releasing the developer material therefrom. In this way, the radial magnetic forces are suitably adjusted to optimize attraction and release of the developer material from the developer roller.