Abstract: A color image forming apparatus including: a plurality of drum-type photoconductors for forming an image in a different color on each peripheral surface and the photoconductors having at least two different diameters; a plurality of driving sections for driving each photoconductor at a driving speed in accordance with the diameter so that each photoconductor rotates at a predetermined peripheral speed; a correction signal output section for outputting a speed correction signal to correct a periodic pitch fluctuation included in each formed image; and a drive control section for controlling the driving section to correct the driving speed of each photoconductor by the speed correction signal, wherein the speed correction signal is a signal having the same cycle as a rotational cycle of each photoconductor.

Abstract: An image forming apparatus include: a plurality of photosensitive drums; a latent image forming unit for forming an electrostatic latent image on each photosensitive drum; a developing unit for developing each electrostatic latent image; a transferring unit for superimposing and transferring the developed images onto a moving record medium; a measurement unit for measuring positions of the transferred images on the record medium; and a control unit for controlling the photosensitive drums, the latent image forming unit, the developing unit, and the transferring unit. The control unit includes: a calculating unit for calculating a value related to alignment errors in the positions measured by said measurement unit in accordance with a sine-curve fitting method; and a correcting unit for correcting the alignment errors by the calculated value.

Abstract: An image forming apparatus includes a controller for detecting the opening and closing of a shutter from the output from an optical sensor and controlling the opening and closing operation of the shutter based on the detected result. The controller determines that if the optical sensor is turned “ON” within a predetermined period of time from when the shutter begins opening, the operation of the shutter from the closed state to the open state is correctly detected. When no reflected light is detected by the optical sensor even after a predetermined time has elapsed, the controller determines that an anomaly has occurred and closes the shutter and repeat another detecting process.

Abstract: In an embodiment of the present invention, an image forming apparatus includes a transfer belt that primarily transfers a toner image formed on a photosensitive drum; a secondary transfer unit including a transfer mechanism portion that secondarily transfers the primarily transferred toner image to a paper; an optical sensor that detects a reference toner image on the transfer belt; and a shutter that protects a detection face of the optical sensor, wherein a separation/contact mechanism portion disposed so as to be brought into contact with both of the shutter and the secondary transfer unit is provided, and the separation/contact mechanism portion allows the shutter to move so as to open and allows the secondary transfer unit to move so as to separate from the transfer belt when the reference toner image is detected by the optical sensor, and allows the shutter to move so as to separate from the transfer belt when the secondary transfer unit is drawn out from an apparatus main body.

Abstract: There is provided an image forming apparatus that includes couplings for photoreceptor drums, couplings for waste toner transporting screws, and couplings for developing rollers, that transmit driving force to each of a plurality of driving shafts for driving a process portion that performs image formation by an electrophotographic method, and a plurality of coupling attaching/detaching members for attaching/detaching the plurality of coupling members, so as to drive the process portion. In the image forming apparatus, the plurality of coupling attaching/detaching members are provided so as to be movable independently, and the image forming apparatus includes a coupling attaching/detaching member driving mechanism that operates the coupling attaching/detaching members in association with each other.

Abstract: A sub CPU of an image forming section forms a toner image based on test line data on an intermediate transfer belt, detects an inclination of the formed toner image for each color component, calculates an adjustment indicative value for correcting the detected inclination for each color component, and outputs the adjustment indicative values to the BK adjusting section, C adjusting section, M adjusting section, and Y adjusting section, respectively, of an inclination adjusting section. The BK adjusting section, C adjusting section, M adjusting section, and Y adjusting section generate, based on the respective adjustment indicative values obtained from the sub CPU, adjustment amounts for an inclination adjustment process to be executed on image data, execute the inclination adjustment process based on the generated adjustment amounts, and output the obtained image data to the respective LDs of an exposure unit.

Abstract: It is an object to prevent distortions and deviations of images caused by the eccentricity of a driven gear mounted to a rotational shaft of a photosensitive drum. There are provided a driving gear which is secured to a rotational shaft of a rotational driving power source and is rotated at a constant peripheral speed, a driven gear secured coaxially to a rotational shaft of a cylindrical-shaped photosensitive member, a phase control gear having the same diameter as that of the driven gear and having the same rotational speed variation characteristic as that of the driven gear, and a transmission gear, and a driving force from the driving gear is transmitted to the driven gear through the phase control gear and the transmission gear.

Abstract: An image forming apparatus with an image adjusting function using a adjustment patterns transferred on an endless belt including; a calculation unit that obtains, based on the measured positions of the adjustment patterns, a deviation in a rotating direction and/or in a width direction, respectively; and an adjustment unit that adjusts an image to be formed based on each obtained deviation, the adjustment patterns including a first oblique pattern obliquely intersecting with one straight line extending in the width direction of the endless belt in a right front direction and a second oblique pattern obliquely intersecting with the line in a left front direction, the calculation unit obtaining the deviation in the rotating direction from an average of the deviations of the first and second oblique pattern in the rotating direction and obtaining the deviations of the first and second oblique pattern in the width direction, respectively.

Abstract: An LD switch is turned ON to output image data outputted from an image processing section to a laser diode, and to irradiate a laser light to a photosensitive drum. The number of pixel dots included in the image data outputted from the image processing section is computed by line basis to detect an image density based on the total sum of the pixel dots of each color at a timing when the image data of Nth line is outputted from the image processing section. The detected image density is compared with a threshold value to turn OFF the LD switch at a timing when the image data of (N+?)th line is outputted when the image density is greater than the threshold value. This suppresses a variation in a rear-end-void length due to sheet slippage.

Abstract: An image forming apparatus including: image forming sections, each image forming section forming an image of a color component among plural color components under a predetermined condition, and forming a pattern of each color component for adjusting the condition; a detecting section that reads the formed patterns so as to perform a temporary detection and a main detection of a deviation from a reference under the condition; and a correction control section that determines whether the deviation of the temporary detection exceeds a predetermined threshold value or not, and when the deviation exceeds the threshold value, executes the main detection to fully detect the deviation so as to correct the condition, wherein the correction control section controls to form the pattern for the temporary detection, the number of the color components for the temporary detection being fewer than those of the patterns to be used for the main detection.

Abstract: An image forming apparatus including: an output image forming section for forming an image and a pattern on a supporting medium under a prescribed condition; an output section for transferring the formed image on a recording sheet; a correction section for performing reading of the formed pattern and correcting the condition based on a result of the reading; and a correction control section for controlling operations of the output image forming section, the output section, and the correction section, wherein the correction control section identifies whether or not an area where the image is to be formed and an area where the pattern is to be formed overlap each other, and when the areas are identified that they do not overlap each other, the correction control section controls the output image forming section to simultaneously form the image and the pattern in parallel on the supporting medium.

Abstract: A color image forming apparatus including: a plurality of drum-type photoconductors for forming an image in a different color on each peripheral surface and the photoconductors having at least two different diameters; a plurality of driving sections for driving each photoconductor at a driving speed in accordance with the diameter so that each photoconductor rotates at a predetermined peripheral speed; a correction signal output section for outputting a speed correction signal to correct a periodic pitch fluctuation included in each formed image; and a drive control section for controlling the driving section to correct the driving speed of each photoconductor by the speed correction signal, wherein the speed correction signal is a signal having the same cycle as a rotational cycle of each photoconductor.

Abstract: A color registration method in a color image forming apparatus including a plurality of drum-type photoconductors for driving some or all of the photoconductors having the same diameter to match pitch fluctuations which correspond to a rotational cycle of the photoconductors, the method including: a first measurement step for forming a first registration image for each color and measuring formation positions of a plurality of predetermined portions in each registration image; a second measurement step for forming a second registration image for each color and measuring formation positions of a plurality of predetermined portions in each registration image; a calculation step for calculating a periodic fluctuation component being contained in the images in different colors and corresponding to the rotational cycle of the photoconductors so as to obtain phases thereof; and a step for adjusting a rotational phase of the photoconductors in order for the obtained phases matching to each other, wherein the interval

Abstract: A refining agent containing Al, MgO and CaO as main components, wherein dolomite is a MgO source and a CaO source. When the refining agent is supplied into molten iron, Mg vapor is produced due to a reaction in the molten iron, and causes a refining reaction by the Mg vapor.

Abstract: A refining agent contains Al, MgO, and CaO as main components, and uses dolomite as a MgO source and CaO source. When the refining agent is supplied into molten iron, it produces Mg vapor due to a reaction in the molten iron, and causes a refining reaction by the Mg vapor.

Abstract: The present invention provides a method of desulfurizing hot metal, which method utilizes desulfurization slag resulting from a KR hot metal desulfurizing treatment as a desulfurizing agent for hot metal again to reduce hot metal desulfurization costs and the amount of slag generated, thereby solving environmental problems.

Abstract: A method for blowing oxygen in a converter uses a top-blown lance having a Laval nozzle installed on its tip. The Laval nozzle has a back pressure of the nozzle Po(kPa) satisfying a formula, Po=FhS/(0.00465·Dt2), with respect to a oxygen-flow-rate FhS(Nm3/hr) per hole of the Laval nozzle determined from the oxygen-flow-rate FS(Nm3/hr) in a high carbon region in a peak of decarburization and a throat diameter Dt(mm). An exit diameter De of the Laval nozzle satisfies the following formula with respect to the back pressure of the nozzle Po(kPa), an ambient pressure Pe(kPa), and the throat diameter Dt(mm): De2≦0.23×Dt2/{(Pe/Po)5/7×[1−(Pe/Po)2/7]1/2}.

Abstract: The present invention provides a method of desulfurizing hot metal, which method utilizes desulfurization slag resulting from a KR hot metal desulfurizing treatment as a desulfurizing agent for hot metal again to reduce hot metal desulfurization costs and the amount of slag generated, thereby solving environmental problems.

Abstract: An apparatus for melting a metal provided with a metal melting furnace (10) for melting a metallic raw material with a flame of an oxygen fuel burner (11) to which oxygen is supplied as a combustion assisting gas; and an oxygen supply source for supplying oxygen as a combustion assisting gas to the oxygen fuel burner (11). The metal melting furnace (10) has a preheating section (13) for preheating the metallic raw material above a melting section (12) to which the oxygen fuel burner (11) is attached and a reduced section (14) located between the melting section (12) and the preheating section (13), the reduced section having an inside diameter smaller than those of the melting section and preheating section. The oxygen supply source is a pressure swing adsorption separator (30) employing an adsorbent which adsorbs preferentially atmospheric nitrogen and supplying a low-purity oxygen having an oxygen content of 65 to 94% to the oxygen fuel burner (11).

Abstract: A method for blowing oxygen in a converter uses a top-blown lance having a Laval nozzle installed on its tip. The Laval nozzle has a back pressure of the nozzle Po(kPa) satisfying a formula, Po=FhS/(0.00465·Dt2), with respect to a oxygen-flow-rate FhS(Nm3/hr) per hole of the Laval nozzle determined from the oxygen-flow-rate FS(Nm3/hr) in a high carbon region in a peak of decarburization and a throat diameter Dt(mm). An exit diameter De of the Laval nozzle satisfies the following formula with respect to the back pressure of the nozzle Po(kPa), an ambient pressure Pe(kPa), and the throat diameter Dt(mm).