Fujitsu Corporation

Hirohiko Kubo

Masato Ishii

Wataru Miki

Tetsuya Fujimoto

Toshio Fukushima

Tatsuhiro Taniwa

Masanori Tokuhisa

An inexpensive large-capacity paper hopper capable of energizing a paper feed table with a constant lift force irrespective of the quantity of paper sheets remaining thereon, thereby performing stable paper feeding. To achieve such a paper hopper, a paper hopper, wherein a paper feed table is lifted or lowered being kept in a horizontal condition and paper sheets stacked on the paper feed table are sequentially sent out from the top sheet for feeding, is arranged such that the paper feed table is so suspended by a wire suspending device as to be lifted or lowered in a horizontal condition, and an elastic tensile force of extension coil springs included in a lift force exerting device is so exerted to the paper feed table that the direction in which the restoring displacement of the extension coil springs takes place becomes coincident with the direction of lifting the paper feed table.

Paper hopper

An electrophotographic recording apparatus including a light-sensitive drum for carrying toner images developed thereon, and a transfer unit arranged at a prescribed distance from the light-sensitive drum for transferring the toner images from a light-sensitive drum to the image recording paper. The transfer unit has a charging wire electrode for electrically charging the paper and a generally inverted U-shaped housing having spaced sidewalls with respective bottom edges. A separator is provided for separating the paper from the light-sensitive drum as the paper travels along a conveying path and comprises a paper separating plate extending from the downstream one of the bottom edges of the housing of the transfer unit in the downstream direction of the travel of the paper along the conveying path side thereof, with and the housing of the transfer unit is grounded. The paper separating plate has a distal end having a saw tooth shape along the length thereof, as measured transversely to the conveying path.

Means for separating image recording medium in electrophotographic

An image forming apparatus includes a developing unit and a photoconductive drum. A toner sensor is disposed in a toner mixing chamber of the developing unit. A mixing member is included in the chamber for mixing and frictionally charging the toner. A detection device is mounted on the unit for detecting the residual quantity of density of the toner according to the output voltage of the sensor. The residual quantity or density of the toner is detected by sampling an output voltage of the toner sensor at predetermined times during a predetermined period while the mixing member is rotated at a specific constant speed, and averaging the sampled vales. As a result correct data for the residual quantity or density of the toner can be obtained.

Growing community of inventors

Hyogo, Japan

Hirohiko Kubo