GB1251670A - - Google Patents

Abstract

1,251,670. Electro-photographic copying apparatus. W. ZINDLER [trading as LUMOPRINT ZINDLER K.G. Nov.15, 1968 [Nov. 17, 1967], No. 54437/68. Heading G2H. A device for replenishing the toner in the developing tank 51 of an electro-photographic copying apparatus is arranged to supply the toner automatically after the passage of each copy sheet, or after the passage of two, three or four copy sheets in succession between a continously rotating roller 21 and an intermittently rotatable roller 22. A manual over-ride of the selected frequency is provided. A copy sheet is inserted in the gap between the rollers 21, 22 and insertion of an original depresses a lever so that the roller 22 is rotated under spring action until its curved surface contacts the roller 21 to complete the rotation through 360 degrees. General Principle. The roller 22 (corresponding to roller 10 of Fig. 1) carries a cam 9 having a recess 11. As the recess 11 is rotated, an arm 8 of a control lever 6 drops into the recess, thereby allowing the other, hooked arm 7 to rise clear of a dog 2 on a dog roller 1, which is thereby free to rotate, it being intermittently connected with the driving roller 21. Movement of the cam 9 brings the arm 8 out of the recess 11 and the arm 7 hooks over the next dog 3, on the curved surface of the dog roller 1. As shown, the roller 10 must make four rotations (corresponding to the passage of four copy sheets) for the dog roller 1 to rotate through 360 degrees. In the embodiment of Figs. 2-4 (not shown), the lever 6 is axially displaceable by virtue of the rotation of an eccentrically mounted square sectioned member 18 so as to engage four, three, two or one dogs of the dog roller for each rotation thereof. In the embodiment of Figs. 5-7 (not shown), the dog roller 1 is axially displaceable by virtue of the rotation of a similar member 18. Replenishment. The dog roller 1 is provided with an actuating lug (45) Figs. 2, 3 and 7 (not shown) which, after the roller 1 has rotated through 360 degrees, trips a plate (57) to move a lever 46, which in turn opens a valve 48 to allow toner to fall into the tank 51. The plate (57) is released before the next dog of the roller 1 is hooked by the arm 7. A push button (63) is provided for manual over-ride.