Abstract: A fixing apparatus including: a cooling unit which cools a non-sheet-passing area for a small-sized sheet of a fixation area to suppress a temperature rise of the non-sheet-passing area; a temperature detecting unit which detects temperatures of a central portion of a sheet-passing area and the non-sheet-passing area; and a fixing-temperature controller which performs an early-heating, restart-control operation to decrease the temperature of the non-sheet-passing area by the cooling unit for a fixation operation of a large-sized sheet while the heat source is de-energized after a fixing operation of the small-sized sheet is completed, and thereafter restart the energization of the heat source during the cooling-down operation by the cooling unit when the temperature of the non-sheet-passing area is lowered to a set target value lower than a controlled fixing temperature for fixing a toner image to the sheet.

Abstract: A fixing apparatus including: a cooling unit which cools a non-sheet passing area for a small sized sheet of a fixation area to suppress a temperature rise of the non-sheet passing area; a temperature detecting unit which detects temperatures of a central portion and the non-sheet passing area; and a fixing temperature controller which performs an early heating restart control operation to decrease the temperature of the non-sheet passing area by the cooling unit for a fixation operation of a large sized sheet while the heat source is de-energized after a fixing operation of the small sized sheet is completed, and thereafter restart the energization of the heat source during the cooling-down operation by the cooling unit when the temperature of the non-sheet passing area is lowered to a set target value lower than a controlled fixing temperature for fixing a toner image to the sheet.

Abstract: The contact rate between a heater 1 and a heater holder 2 is made higher at both ends in the longitudinal direction of the heater than at the center. Alternatively, the per-unit-length volume of the heater holder 2 in the longitudinal direction is made larger at the both ends in the longitudinal direction of the heater. In this configuration, the heat generated by the heater can easily escape into the heater holder side at the both ends but cannot easily escape into the heater holder side at the center. Although the per-unit-length heat amount in the longitudinal direction of the heater 1 may be even, it is also possible to set the heat amount distribution in such a way that the heat amount at the both ends is larger than that at the center.

Abstract: It is an object of the present invention to provide a hydraulic-free automatic swiveling turret apparatus which can easily ensure a swiveling function that is smooth and superior in terms of durability using a simple construction without any need to install a hydraulic pressure reducing mechanism requiring complicated design and control.

Abstract: It is an object of the present invention to provide a hydraulic-free automatic swiveling turret apparatus which can easily ensure a swiveling function that is smooth and superior in terms of durability using a simple construction without any need to install a hydraulic pressure reducing mechanism requiring complicated design and control.

Abstract: The contact rate between a heater 1 and a heater holder 2 is made higher at both ends in the longitudinal direction of the heater than at the center. Alternatively, the per-unit-length volume of the heater holder 2 in the longitudinal direction is made larger at the both ends in the longitudinal direction of the heater. In this configuration, the heat generated by the heater can easily escape into the heater holder side at the both ends but cannot easily escape into the heater holder side at the center. Although the per-unit-length heat amount in the longitudinal direction of the heater 1 may be even, it is also possible to set the heat amount distribution in such a way that the heat amount at the both ends is larger than that at the center.

Abstract: The contact rate between a heater 1 and a heater holder 2 is made higher at both ends in the longitudinal direction of the heater than at the center. Alternatively, the per-unit-length volume of the heater holder 2 in the longitudinal direction is made larger at the both ends in the longitudinal direction of the heater. In this configuration, the heat generated by the heater can easily escape into the heater holder side at the both ends but cannot easily escape into the heater holder side at the center. Although the per-unit-length heat amount in the longitudinal direction of the heater may be even, it is also possible to set the heat amount distribution in such a way that the heat amount at the both ends is larger than that at the center.

Abstract: The temperature “t” sensed at the end in the longitudinal direction of a heater is compared with a threshold Th and, based on the comparison result, the print speed (throughput) is controlled. The threshold Th is switched according to a predetermined condition. For example, whether the number of times the throughput reduction, which switches the print speed to a lower speed, is executed has reached a predetermined number is used as the predetermined condition. Alternatively, whether the small-size-paper passing ratio is higher than a predetermined value is used as the predetermined condition. This prevents grease runoff, provides good slidability between a fixing film and the heater, solves problems of improper paper conveyance, sliding sound generation, and improper fixing, and improves the durability of a fixing device.

Abstract: The contact rate between a heater 1 and a heater holder 2 is made higher at both ends in the longitudinal direction of the heater than at the center. Alternatively, the per-unit-length volume of the heater holder 2 in the longitudinal direction is made larger at the both ends in the longitudinal direction of the heater. In this configuration, the heat generated by the heater can easily escape into the heater holder side at the both ends but cannot easily escape into the heater holder side at the center. Although the per-unit-length heat amount in the longitudinal direction of the heater may be even, it is also possible to set the heat amount distribution in such a way that the heat amount at the both ends is larger than that at the center.

Abstract: The temperature “t” sensed at the end in the longitudinal direction of a heater is compared with a threshold Th and, based on the comparison result, the print speed (throughput) is controlled. The threshold Th is switched according to a predetermined condition. For example, whether the number of times the throughput reduction, which switches the print speed to a lower speed, is executed has reached a predetermined number is used as the predetermined condition. Alternatively, whether the small-size-paper passing ratio is higher than a predetermined value is used as the predetermined condition. This prevents grease runoff, provides good slidability between a fixing film and the heater, solves problems of improper paper conveyance, sliding sound generation, and improper fixing, and improves the durability of a fixing device.

Abstract: It is to provide an image forming apparatus capable of reducing a processing time and of forming an image without high-temperature offset and defect of fixing when images are continuously formed. The image forming apparatus has number of sheets storing means for storing the number of passing sheets upon previous continuous-image-formation; counter means for counting a passing time from the end time of the continuous image formation; and a CPU for, when the images are continuously formed at this time, limiting the number of sheets image-formed at a first copying speed at which the number of sheets is large per unit time to a predetermined number of sheets, based on the number of recorded sheets and the passing time upon the previous continuous-image-formation and for, when the number of sheets is over the limited number of sheets, changing the first copying speed to the second copying speed at which the number of sheets per unit time is small.

Abstract: It is to provide an image forming apparatus capable of reducing a processing time and of forming an image without high-temperature offset and defect of fixing when images are continuously formed. The image forming apparatus has number of sheets storing means for storing the number of passing sheets upon previous continuous-image-formation; counter means for counting a passing time from the end time of the continuous image formation; and a CPU for, when the images are continuously formed at this time, limiting the number of sheets image-formed at a first copying speed at which the number of sheets is large per unit time to a predetermined number of sheets, based on the number of recorded sheets and the passing time upon the previous continuous-image-formation and for, when the number of sheets is over the limited number of sheets, changing the first copying speed to the second copying speed at which the number of sheets per unit time is small.

Abstract: A two-component developer suitable for use with an image-forming apparatus which permits the removal and recovery of a toner remaining on a photoconductive drum after the transfer of the toner to a receptor sheet without using cleaning means, comprisinga toner formed of toner matrix particles containing a binder resin and a colorant as main components, and a magnetic powder adhering to a surface of each toner matrix particle, anda magnetic carrier having a saturation magnetization of 90 to 200 emu/g in an external magnetic field of 3,000 oersted.

Abstract: In a thermal printer for thermo-sensitive recording, a plurality of heating resistors are electrically divided into N units each having M heating resistors, and N driver circuits, N latch circuits and N shift registers which are interconnected in tandem are respectively provided in association with the N units of M heating resistors. Dot data signals and associated hysteresis correction signals are collectively applied to the shift registers so that a pulse for print data and a pulse for hysteresis correction data can be applied continuously for printing.

Abstract: The present invention relates to a printer, and more particularly to a heat transfer printer. The printer comprises: a pair of upper and lower chutes for guiding printed paper; an idle roller provided on the upper chute; a paper discharging motor bracket provided on the lower chute; a paper discharging lever rotatably provided on the paper discharging motor bracket; and a paper discharging pulley disposed at a tip of the paper discharging lever, wherein, at the time of discharging the paper, the paper discharging lever is rotated by a driving force of a motor provided on the bracket to cause the paper discharging pulley to project from the lower chute so as to come into contact with the idle roller, while, at the time of printing, the motor is stopped.

Abstract: A magnetic head having a sputter-deposited glass film of the gap forming area of the magnetic core, said glass film being made of borosilicate glass having the composition consisting of 65-85 mol % of SiO.sub.2, 8-30 mol % of B.sub.2 O.sub.3 and containing 2-15 mol % of alkali metal oxide Na.sub.2 O and K.sub.2 O and 0.1-5 mol % of Al.sub.2 O.sub.3, with the molar ratio of boron oxide to alkali metal oxides being defined by the following formula: ##EQU1## The magnetic head provides sharpness of the recording leakage flux, thus giving excellent electromagnetic conversion characteristics.