Abstract: A method for folding a jacket material mainly for a magnetic cartridge, by using a folding insert, a folding bar and a heater bar, into a jacket of good external shape and high dimensional precision with a folded edge entirely free from loosening, warping, waving, swelling, etc.

Abstract: An apparatus for folding a jacket material, used mainly for a magnetic cartridge, is characterized by using a folding insert, a folding bar, and a heater bar, to form the jacket material into a jacket of good external shape and high dimensional precision with a folded corner entirely free from loosening, warping, waving, swelling, etc.

Abstract: An electrophotographic process includes the steps of forming a visible image composed of coloring particles on a photosensitive member having a surface insulating layer, providing the visible image with an electrostatic charge by first corona discharge, bringing a transfer sheet into contact with the photosensitive member, providing the rear surface of the transfer sheet with a predetermined amount of an electrostatic charge of a polarity opposite to that of the charge on the coloring particles by second corona discharge thereby transferring the visible image onto the transfer sheet, and providing the rear surface of the transfer sheet with an electrostatic charge, which is the same in polarity as that of the coloring particles but is less in the amount than that provided by the second corona discharge, thereby separating the transfer sheet from the photosensitive member, and an apparatus adapted for executing the above-mentioned process.

Abstract: An electrophotographic process including forming, on a photosensitive plate, an electrostatic latent image corresponding to optical information, developing the latent image by the reversal development and transferring the developed image onto a transfer material includes the improvement whereby a voltage of polarity opposite to that of the developer is applied to the photosensitive plate at least during the time from the end of the reversal development to the transfer step. This improvement in the electrophotographic process and apparatus for same prevents developer particles from being scattered away from the photosensitive plate and thereby also avoids the trouble of distortion of the image at the transfer step.

Abstract: In charging a surface of a chargeable member by AC corona discharge, the current difference between the plus and the minus component of the AC corona discharge current is detected, and the current difference is maintained constant to thereby stably produce a constant surface potential on the chargeable member.

Abstract: An electrostatic latent image developing method and a device therefor, featured in supplying one-component magnetic developer onto a developer-feeding non-magnetic bearing member to form thereon a magnetic brush of developer under the effect of a magnetic field, then bringing said magnetic brush into contact with the surface of an image-developing developer bearing member to form thereon a thin uniform layer of the developer, and bringing said thin layer to a developing position to develop an electrostatic latent image formed on a latent image bearing member. At the development the thin layer of the developer is so spaced in the developing position from the latent image bearing surface as to form a clearance therebetween, across which an AC bias electric field is applied.

Abstract: An image developing device capable of forming a magnetic brush of one-component developer on a developer-feeding magnetic brush roller, and bringing said magnetic brush into contact with a developing roller to form a thin layer of the one-component developer thereon. In the mutually facing area between the rollers the magnetic force of the developing roller for transporting the developer is selected smaller than that of the magnetic brush roller for transporting the developer. The magnetic brush roller and the developing roller are rotated in a same direction so that they are moved mutually oppositely at the mutually facing area thereof.

Abstract: An image forming apparatus includes a plurality of devices for forming an image on a rotatable medium and transferring the image onto transfer material. A detector is provided to detect the electrical condition of one of the devices during an initial turn of the rotatable medium prior to image processing. Electrical circuitry then controls the electrical condition of the one device to approach a predetermined value which value is then held for controlling the device during image formation.

Abstract: A transfer corona current is always maintained substantially constant independently of the surface potential of a photosensitive medium and environmental conditions, to thereby prevent the amount of charge on the back side of a transfer medium from fluctuating in accordance with said surface potential and environmental conditions. In addition, a separation corona current is maintained substantially constant to thereby further improve the stability of electrostatic separation. The transfer corona current is below a critical current value whereat the corona charge passes through the transfer medium, and the separation corona imparts to the back side of the transfer medium an amount of charge substantially equal to the amount of charge provided by the transfer corona.

Abstract: A liquid feeding device for feeding a liquid accommodated in a reservoir through a liquid holding member to an object, onto which the liquid is to be fed, wherein the liquid holding member takes up the liquid in the reservoir and holds the same therein, and the feeding quantity of the liquid to the object can be maintained constant by controlling a vertical distance between the liquid surface level in the reservoir and a point where the liquid holding member and the object contact each other, this vertical distance being made variable depending on whether the device is in operation, or not, and on the liquid temperature as well.

Abstract: In a corona discharger having a corona discharge wire to which a voltage is applied to induce discharge, a member for absorbing vibration of the discharger is supported so as to make contact with the discharge wire at least during vibration thereof.