Toshiba Tec Kabushiki Kaisha

Other

Kabushiki Kaisha Toshiba

Hisaaki Kawano

Osamu Takagi

Satoshi Kinouchi

Kazuhiko Kikuchi

Hiroshi Nakayama

Masahiko Ogura

Kenji Takano

Taizo Kimoto

Noriyuki Umezawa

Yasufumi Tanimoto

Noiryuki Umezawa

Kouji Ishida

The present invention provides a fixing device and a digital photocopier which can shorten the time from an instruction of starting image formation to end of fixing. The fixing device is provided in a cylinder made of metal and having a small thickness, and includes a magnetic excitation coil. When the power source is turned on, all the electric power defined by subtracting an electric power amount consumed by components other than the fixing device is supplied to the magnetic excitation coil to perform heating. As the structural components of the photocopier and auxiliary devices added to the photocopier operate, the electric power defined by subtracting, from the maximum input electric power, the electric power consumed by the structural components of the photocopier and the auxiliary devices is supplied to perform heating. In this manner, the heat roller of the fixing device is heated, in a short time, to a temperature which enables fixing, so that the time required for first copying can be shortened.

Image forming apparatus and fixing device

An electrophotographic fixing device allowing a flow of an AC current through an electromagnetic induction coil arranged close to a heating roller having a metal layer formed of a conductor and allowing the heat generation of the heating roller to heat a to-be-fixed member, in which the fixing device comprises a circuit board for outputting the AC current from an output terminal and passing the current through the electromagnetic induction coil, a conductive plate metal having one end side fixed by a fastening screw to the output terminal of the circuit board, a male-side connection terminal provided on the other end of the plate metal, and a female-side connection terminal provided at an end of a leader line of the electromagnetic induction coil and detachably connected to a male-side connection terminal.

Fixing device that is detachable from an image forming apparatus

Fixing device

A fixing device comprising an endless heating member which is adapted to be contacted with a fixable member to thereby enable an image on the fixable member to be thermally fixed, an electromagnetic inductive coil member disposed close to the endless heating member and inductively heating the endless heating member, and an AC power supply circuit supplying an AC current to the electromagnetic inductive coil member. The coil member is constructed such that in a state where the coil member is positioned in the fixing device, a ratio between an inductance L of the coil member and a load resistance R of the coil member meets a condition of L/R<50&times;10 (H/&OHgr;).

Fixing device including an electromagnetic inductive coil member providing inductive heating

An electrophotographic fixing device allowing a flow of an AC current through an electromagnetic induction coil arranged close to a heating roller having a metal layer formed of a conductor and allowing the heat generation of the heating roller to heat a to-be-fixed members. The fixing device comprises a circuit board for outputting the AC current from an output terminal and passing the current through the electromagnetic induction coil. A connection plate having a thickness twice or more the current penetration depth and having one end side fixed by a fastening screw to the output terminal of the circuit board, and a male-side connection terminal provided on the other end of the plate metal. A female-side connection terminal provided at an end of a leader line of the electromagnetic induction coil is detachably connected to the male-side connection terminal.

Fixing device having connection member for supplying AC current to an electromagnetic induction coil

The present invention is a fixing device for use in an electrophotographic apparatus arranged in a structure in which a high-frequency current is flowed through an induction coil provided close to an endless member having a metal layer made of a conductive material and the endless member is caused to generate heat to heat a material to be fixed. This fixing device is characterized in that, when a start-up operation is started by electrically conducting the induction coil, the endless member is rotated after the metal layer reaches a temperature higher than a final setting temperature, and for a predetermined time from starting rotation of the endless member, a high-frequency current having a size corresponding to a control value of a temperature lower than the final setting temperature and higher than a target temperature is supplied to the coil.

Image forming apparatus and fixing device for fixing a toner image to a fixing device

When a voltage abnormality error signal from a drive control section is at a low level, a control section determines a normal state. When the voltage abnormality error signal has arisen to a high level, the control section does not immediately determine an abnormal state and instead measures a time in which the voltage abnormality error signal is at the high level. If the measured time does not exceed a predetermined error timer value (limit value) T, the control section ignores this abnormal state as a temporary voltage abnormality. If the time in which the voltage abnormality error signal is at the high level exceeds the error timer value T, the control section determines a serviceman call error (SC) as the occurrence of voltage abnormality.

Image forming apparatus having fixing device for fixing developer image on recording medium by induction-heating heat roller

Fixing device using induction heating as a heating source

An image forming apparatus for forming an image on paper has a controller for changing paper feed intervals of a feeding device based on a mode set by a setting device. The controller may stop the feeding of the paper by the feeding device based on a temperature at an end portion of the fixing device detected by a temperature detector. The controller may control the paper feed intervals in such a manner that the paper feed intervals are small for a paper having a width greater than a threshold, large for a paper having a width; equal to or less than the threshold with no designation of a high using frequency, and small for a paper having a width equal to or less than the threshold with a designation of a high using frequency.

Image forming apparatus having a controller for controlling paper feed intervals

The present invention includes individually (independently) a drive control section for driving/controlling an induction heating device of a fixing device and a main-body control section for entirely controlling an electronic copying machine. The start-up processing for the induction heating device is started prior to start-up processing for parts of the main body of the electronic copying machine other than the induction heating device.

Image forming apparatus having a fixing device for fixing developer image on recording medium by subjecting heat roller to induction heating

A high-frequency current is supplied from a high-frequency generating circuit to a coil of a heat roller, and a high-frequency magnetic field is generated from the coil. The high-frequency magnetic field causes an eddy current to be generated in the heat roller, and a developer image on a recording medium is fixed by self-generation of heat of the heating roller based on an eddy-current loss. Electric wires between the high-frequency generating circuit and the coil are electrically shielded by a shield member.

Fixing device for fixing a developer image on a recording medium by induction-heating a heat roller

In an image forming apparatus, a developing unit for developing a latent image on a photosensitive drum is detachably mounted in the apparatus and is provided with a identification signal generator for each particular developing unit. When the developing unit is replaced by a new one, an identification signal generated from the generator is compared in a CPU with reference identification data stored in a memory. When the generated identification signal differs from the stored reference identification data, the generated identification signal is stored as a new reference data in the memory and a toner concentration signal generated from the sensor is also stored as new reference toner concentration data in the memory. Thus, a desired toner concentration can be maintained even through developing units are replaced.

Growing community of inventors

Chigasaki, Japan

Hisaaki Kawano