Abstract: An image forming apparatus includes an image bearing member for bearing an image. A charging device is supplied with a voltage. The charging device includes a magnetic brush contactable to the image bearing member to electrically charge the image bearing member. A developing device develops, at a developing position, an electrostatic image formed on the image bearing member using a charging operation of the charging device, with toner having the same polarity as a charging polarity of the charging device, into a toner image. The developing device is capable of removing residual toner from the image bearing member. The developing device stops its developing operation if an area of the image bearing member, which has been charged by the charging device when the charging device is being supplied with an oscillating voltage in the form of superimposed AC and DC voltages, is still at the developing position.

Abstract: An image forming apparatus includes an image bearing member and a charging unit having magnetic particles that are contactable with the image bearing member. An electrostatic image forming unit forms an electrostatic image on the charged image bearing member. A developing device develops an electrostatic image on the image bearing member with toner that includes toner and magnetic carrier. A detecting unit detects the toner content of the developer and a toner supply unit supplies the toner into the developing unit when the detected toner content is lower than a predetermined level. A calculating unit calculates the changing rate of the toner content from an output of the detecting unit and a warning unit warns that a changing rate of the toner content is larger than a predetermined level.

Abstract: The linear motion rolling guide unit of this invention prevents galvanic corrosion by electrically insulating the mounting surfaces of the track rails and the casings as well as the surfaces in contact with other members. The track rails mounted on the base have rail raceway surfaces on both sides thereof. The casings have casing raceway surfaces facing the rail raceway surfaces, are mounted astride the track rails and slide on the track rail. A large number of rolling elements roll between the rail raceway surfaces and the casing raceway surfaces. Insulating members are interposed between the base and the mounting surfaces of the track rails. The mounting surfaces of the casings with respect to the end caps and the table are also provided with insulating members.

Abstract: A stopper assembly for use in a linear motion rolling contact guide unit, including a rail formed with a pair of inner guide grooves, a slider slidably mounted on the rail and formed with a pair of outer guide grooves, each located opposite to a corresponding one of the inner guide grooves to thereby define a guide channel and a plurality of rolling members provided in the guide channel, generally includes a generally U-shaped main body and a bolt. The main body includes a horizontal section and a pair of vertical sections extending vertically from the respective ends of the horizonal section. One of the vertical sections is provided with a projection which is received in one of the inner guide grooves and the other vertical section is provided with a threaded hole in which a bolt extends and has its tip end received in the other inner guide groove.

Abstract: A multi-slider single rail linear motion rolling contact guide unit is provided. The guide unit includes an elongated rail provided with a first pair of guide grooves and a second pair of guide grooves. A first slider is provided with a first pair of endless circulating paths filled with a plurality of rolling members engageable with the first pair of guide grooves, and, similarly, a second slider is provided with a second pair of endless circulating paths filled with a plurality of rolling members engageable with the second pair of guide grooves. Thus, the first and second sliders are slidably mounted on the rail independently from each other.

Abstract: A linear motion rolling guide unit comprising a track rail of substantially rectangularly columnar shape and a slider slidably movable on said track rail, said track rail being formed with arcuate raceway grooves at both right and left shoulders of sidewall surfaces thereof, said slider being formed with an arcuate raceway groove on an inner peripheral surface thereof opposed to the arcuate raceway grooves of said track rail, balls being arranged between said arcuate raceway grooves. Said track rail has bottom mounting portions, relieves are formed longitudinally at both sides of the bottom mounting portions, a relief groove is longitudinally at an axially central position of the track rail so that the width of bottom mounting portions thereof interposed between relieves is smaller than the diameter of the mounting hole of said track rail so as to improve its moving accuracy while maintaining a parallelism between the track rail and an opponent member.

Abstract: A dust-free linear motion rolling contact bearing assembly includes a U-shaped bed of a length, a table and a plurality of rolling members interposed between the bed and the table to provide a rolling contact between the bed and the table. A take-up/supply roller is rotatably mounted at each end of the table and a shield palte has its base end fixedly attached to the take-up/supply roller and has its forward end fixedly attached to the corresponding end of the bed. Thus, as the table moves linearly relative to the bed, the shield plate is either supplied as unwound from the take-up/supply roller or taken up as wound around the take-up/supply roller to keep the opening of the bed covered by the shield plate. Thus, the interior space of the bearing assembly is kept shielded at all times without any scrubbing action between the shield plate and the bed.

Abstract: A dust-free linear motion rolling-contact bearing assembly includes a track rail having a generally U-shaped cross section, a table having a generally inverted U-shaped cross section and received in the track rail and a plurality of rolling members interposed between the table and the track rail such that the table can move along the track rail freely. The present assembly also includes a pair of shielding plates each extending between one end of the table and the corresponding end of the track rail so that, as the table moves along the track rail, the shield plates keep the track rail covered at all times thereby preventing any undesired foreign matter, such as debris and dust, from getting into the assembly.