Abstract: A printing machine including a drum adapted to have a latent image recorded on the surface thereof. The drum is positioned with the longitudinal axis thereof extending in a direction substantially transverse to the horizontal. The latent image is developed with a liquid developer to form a liquid image on the surface of the drum. The liquid image is transferred to a copy sheet. Residual liquid developer removed from the surface of the drum by the cleaning unit, flows in a downwardly direction under the influence of gravity to a liquid collector housing located at the bottom of the cleaning unit.

Abstract: A development station conveys developer material from a sump to a magnetic brush for development of latent images on a photoconductor. The developer material flows through a slot adjacent the magnetic brush. A thin film having a plurality of apertures is positioned adjacent the slot. The film is movable to align the apertures with the slot so that developer material can pass through the slot to the brush. Movement of the film perforations out of alignment with the slot shuts off the flow of developer material to the magnetic brush.

Abstract: An image forming apparatus includes a paper delivery detecting switch provided near the paper delivery opening, a paper presence detecting structure to detect the presence of the paper on the receiving tray, a counter circuit and a comparator. The counter circuit counts up the number of delivered paper on the receiving tray in response to a delivered paper signal from the paper delivery detecting switch and a paper presence signal from the paper presence detecting structure. The comparator compares the value of number of delivered paper counted up by the counter circuit and a delivery quantity limit value preset in the apparatus main body, and halts the image forming operation when the two values coincide.