摘要:
A developing device used in an electrophotographic apparatus has seal members fixedly disposed between both end portions of a developing roller and those portions of inner walls of a device casing which correspond to both end portions of the developing roller. The seal members are made of a material which can be charged by friction with the developing roller to have the same polarity as charged toner. The toner is blocked by the seal members and presented from entering end portions of the developing roller.
摘要:
A transfer device of a contact transfer method wherein a transfer power supply applies a predetermined transfer voltage to a transfer roller contacting the rear surface of a printing sheet, so that an electric field for causing the toner to be attracted by the transfer roller is generated. A lumped constant resistor is electrically inserted between the transfer roller and the transfer power supply. The lumped constant resistor has an electric resistance smaller than an equivalent electric resistance obtained when the whole transfer roller is regarded as one electric resistor. When the electric resistance of the printing sheet changes in accordance with a change in ambient environment, the voltage drop across the lumped constant resistor is changed to compensate for the change in electric resistance of the printing sheet.
摘要:
At start of rotation of a photosensitive drum, rotation of a developing roller caused by a developing/register rollers driver is kept stopped until a time required for a predetermined point on the photosensitive member, which was located at a charging position when charging thereof by a charging device was started, to reach a development position elapses, and thereafter the developing roller is rotated by the developing/register rollers driver. When the predetermined point on the photosensitive member, which was located at the developing position when at least rotation of the photosensitive member was started, passes the transfer position, a roller cleaning voltage having the same polarity as the charge polarity of toner is applied to a transfer roller.
摘要:
In a developing device for developing an electrostatic latent image formed on a photosensitive member in an electrophotographic apparatus, a developing roller and a developing blade are formed such that the hardness of the surface of the developing blade is higher than the hardness of the surface of the developing roller by 30 degrees or more in JIS-A hardness. The developing blade deforms and bites into the developing roller. Accordingly, the developing roller can be brought into tight contact with the developing blade, and a great frictional force is applied to the toner passing between the developing roller and blade to fully charge the toner.
摘要:
A developing device used in an electrophotographic apparatus has seal members fixedly disposed between both end portions of a developing roller and those portions of inner walls of a device casing which correspond to both end portions of the developing roller. The seal members are made of a material which can be charged by friction with the developing roller to have the same polarity as charged toner. The toner is blocked by the seal members and prevented from entering end portions of the developing roller.
摘要:
A toner pack for use in an electrophotographic apparatus is formed of a polypropylene resin containing 30 to 50 wt % calcium carbonate filler. This resin has a high deformability, and generates a small amount of heat at the time of incineration thereof. Thus, the used toner pack can be disposed of together with flammable products made of paper and/or wood. Further, at the time of disposal, it is possible to fold the used toner pack to reduce its size.
摘要:
A developing device includes an agitator rotated in a toner hopper. The agitator has a rod portion. A first coil spring portion is wound around the first portion of the rod portion in a first direction. A second coil spring portion is wound around the second portion of the rod portion in a second direction. The first direction is opposite to the second direction.
摘要:
In an electrophotographic device, a main body is divided into a lower body and a swingable upper body. A process unit formed of at least a toner holder, a charger, and a developer is detachably mounted in the lower body. The position of the process unit (particularly, the photosensitive member) relative to the lower body (particularly, a member driving gear) is controlled by placing a shaft of the member through a groove in a side wall of the lower body at one end of the member, and by bringing a lower end of the side wall of the process unit supporting the member into contact with an upper end of a support member supporting the member driving gear. An exposure unit mounted in the upper body is positioned to the photosensitive member with a predetermined distance therebetween by bringing a contact portion of the exposure head into contact with the side wall of the lower body supporting the member.
摘要:
A fixing device includes a fixing belt movably supported by a rotatable heating member and a rotatable support member equipped with a surface elastic layer having a hardness not higher than 40°. The fixing device also includes a pressurizing mechanism arranged to face the support member with the fixing belt interposed therebetween and equipped with a pressurizing member movable in synchronism with the fixing belt.
摘要:
Disclosed is an decolorizable electrophotographic toner, containing a binder resin, an electron-donating color-developable agent, and a wax having a color-developing action and having an acid value of 60 mgKOH/g or more.