摘要:
A fixing device is provided with a fixing unit for fixing a toner image; a magnetic flux generator including a switching element for generating a magnetic flux; and a control unit for performing a start-up mode for raising the temperature of the fixing unit to a fixing temperature by the magnetic flux and a steady mode for maintaining the temperature of the fixing unit at the fixing temperature. The control unit turns off the switching element when the temperature of the switching element is equal to or higher than a first reference temperature lower than a destruction temperature during a period of the start-up mode, and turns off the switching element when the temperature of the switching element is equal to or higher than a second reference temperature lower than the destruction temperature and higher than the first reference temperature during a period of the steady mode.
摘要:
A fixing device is provided with a fixing unit for fixing a toner image; a magnetic flux generator including a switching element for generating a magnetic flux; and a control unit for performing a start-up mode for raising the temperature of the fixing unit to a fixing temperature by the magnetic flux and a steady mode for maintaining the temperature of the fixing unit at the fixing temperature. The control unit turns off the switching element when the temperature of the switching element is equal to or higher than a first reference temperature lower than a destruction temperature during a period of the start-up mode, and turns off the switching element when the temperature of the switching element is equal to or higher than a second reference temperature lower than the destruction temperature and higher than the first reference temperature during a period of the steady mode.
摘要:
An image forming apparatus, including: a fixing device having: a first heat generator for generating heat for a fixing processing, the first heat generator using electric power supplied by a commercial power source; and a second heat generator for generating heat for the fixing processing, the second heat generator using electric power supplied by the auxiliary power source device; a heat generation controller for allowing the first heat generator and the second heat generator to generate heat; a sheet jam detector for detecting a sheet jam of a recording sheet which occurs in the image forming section having the fixing device and a conveyance path of a recording sheet; and a charge controller for allowing charging of the auxiliary power source device to start when the sheet jam detector detects a sheet jam, and the charged capacity detector detects no full charge of the auxiliary power source device.
摘要:
A controller is operative to heat a first fixing heater by an electric power from a commercial power source, and to heat a second fixing heater by an electric power from an electric storage device in a state that driving of a voltage boosting device is suspended by a PWM controller and an MOS transistor in an initial stage of driving a fixing heater unit. The controller is also operative to drive the second fixing heater by an electric power from the electric storage device which is boosted by the voltage boosting device by driving the voltage boosting device by the PWM controller and the MOS transistor after an inrush current to the second fixing heater has dropped to a certain level.
摘要:
A fixing device comprises a heated member formed into a hollow, cylindrical shape, said heated member including a nonmagnetic portion having a particular length along an axial direction of said heated member, a magnetic flux generator for generating magnetic flux exerted on said heated member, a first magnetic core disposed face to face with said magnetic flux generator with said heated member positioned between said first magnetic core and said magnetic flux generator to form a magnetic circuit which is routed to come out of said magnetic flux generator, pass through said heated member and return to said magnetic flux generator, and a shifting mechanism for varying the length of an area of said heated member along the axial direction thereof where the nonmagnetic portion of said heated member and said first magnetic core face each other.
摘要:
A machine (1) has a capacitor switch (20) for switching between a side to drive a first fixing heater (17) by a capacitor (18), and a side to charge the capacitor (18). A battery switch (25) switches between a side to drive a second fixing heater (22) by a battery (23), and a side to charge the battery (23). A heater switch (27) drives a third fixing heater (26). A judger (152) judges whether the machine (1) is in a first condition requiring a rapid raise in the temperature of a fixing section, or a second condition requiring a maintained temperature of the fixing section. A controller (153) energizes all three fixing heaters (17, 22, 26) when the machine (1) is in the first condition, and energizes the second and third fixing heaters (22, 26) while charging the capacitor (18) when the machine (1) is in the second condition.
摘要:
A machine (1) has a capacitor switch (20) for switching between a side to drive a first fixing heater (17) by a capacitor (18), and a side to charge the capacitor (18). A battery switch (25) switches between a side to drive a second fixing heater (22) by a battery (23), and a side to charge the battery (23). A heater switch (27) drives a third fixing heater (26). A judger (152) judges whether the machine (1) is in a first condition requiring a rapid raise in the temperature of a fixing section, or a second condition requiring a maintained temperature of the fixing section. A controller (153) energizes all three fixing heaters (17, 22, 26) when the machine (1) is in the first condition, and energizes the second and third fixing heaters (22, 26) while charging the capacitor (18) when the machine (1) is in the second condition.
摘要:
In order to efficiently utilize the energy of the flux leaked from the vicinities of the edges of a fixing roller having a part to be heated, which is made of magnetic material that has Curie point, the energy of the leaked flux is stored to be utilized as need arises, or is utilized to heat the vicinity of the center of the fixing roller.
摘要:
Provided is an image forming apparatus, including: a heating section; a coil that is opposed to the heating section, for heating the heating section; a core that has a circumferential surface covered with a magnetic shielding plate having different lengths in an axis direction in a plurality of steps according to a position in a circumferential direction; a rotary section for causing the core to rotate; a plurality of temperature sensing elements for sensing temperatures of the heating section; and a control section for controlling a heating width by controlling the rotary section to control a rotation angle of the core, setting the heating width corresponding to a size of a paper sheet at a start of a print job, and setting the heating width wider than at the start of the print job midway through the print job.
摘要:
An image forming apparatus, including: a fixing device having: a first heat generator for generating heat for a fixing processing, the first heat generator using electric power supplied by a commercial power source; and a second heat generator for generating heat for the fixing processing, the second heat generator using electric power supplied by the auxiliary power source device; a heat generation controller for allowing the first heat generator and the second heat generator to generate heat; a sheet jam detector for detecting a sheet jam of a recording sheet which occurs in the image forming section having the fixing device and a conveyance path of a recording sheet; and a charge controller for allowing charging of the auxiliary power source device to start when the sheet jam detector detects a sheet jam, and the charged capacity detector detects no full charge of the auxiliary power source device.