摘要:
A developing apparatus in which a stationary multipole permanent magnet (4) is placed in a sleeve (3) and in which a development is performed by bringing a developer (7), which contains at least carrier and toner particles and is held on the periphery of a sleeve (3) by use of the magnetic force of the multipole permanent magnet (4), into contact with a photo-conductive body (1) owing to the rotation of the sleeve (3). For securing of image density and for preventing of the deposition of carrier onto the photo-conductive body (1), two magnetic pieces (18, 19), each of which is arranged lengthwise in the direction of the axis thereof and has same polarity, are placed in a region in the multipole permanent magnet (4), which faces the photo-conductive body (1), in such a manner as to adjoin in the circumferential direction of said permanent magnet (4). This results in generation of the distribution of a magnetic field, which have two peaks of the magnetic force. The position, at which a second one of the two peaks of the magnetic force is formed downstream in the direction of rotation of the sleeve (3), is set at the nearest point between the photo-conductive body (1) and the sleeve (3). Thereby, even when a development is performed by bringing the developer (7) into light contact with the photo-conductive body (1), the image density can be secured. Further, the carrier can be prevented from depositing on the photo-conductive body (1).
摘要:
A developing apparatus in which a stationary multipole permanent magnet (4) is placed in a sleeve (3) and in which a development is performed by bringing a developer (7), which contains at least carrier and toner particles and is held on the periphery of a sleeve (3) by use of the magnetic force of the multipole permanent magnet (4), into contact with a photo-conductive body (1) owing to the rotation of the sleeve (3). For securing of image density and for preventing of the deposition of carrier onto the photo-conductive body (1), two magnetic pieces (18, 19), each of which is arranged lengthwise in the direction of the axis thereof and has same polarity, are placed in a region in the multipole permanent magnet (4), which faces the photo-conductive body (1), in such a manner as to adjoin in the circumferential direction of said permanent magnet (4). This results in generation of the distribution of a magnetic field, which have two peaks of the magnetic force. The position, at which a second one of the two peaks of the magnetic force is formed downstream in the direction of rotation of the sleeve (3), is set at the nearest point between the photo-conductive body (1) and the sleeve (3). Thereby, even when a development is performed by bringing the developer (7) into light contact with the photo-conductive body (1), the image density can be secured. Further, the carrier can be prevented from depositing on the photo-conductive body (1).
摘要:
Disclosed is an electrical power supply (18) for use, for example, for a flush fusing device in an electrophotographic recording apparatus, in which a DC high voltage is generated from a low voltage of a AC power supply (11) so that the high voltage DC energy is momentarily consumed or discharged. The electrical power supply (18) is configured in a manner so that, in order to make unnecessary a charging capacitor and a current limiting resistor for preventing rectifier elements from being damaged, at least a part of the rectifier elements are constituted by rectifying control elements such as thyristors or transistors (5, 6) and a control signal is given to those rectifying control elements so as to make the rectifying control elements be in an isolated state. By use of such a configuration, the electrical power supply (18) can be reduced in size as well as in power loss. The effect can be fully exhibited not only in a fusing apparatus employing the electrical power supply but in a recording apparatus employing such a fusing apparatus.
摘要:
Disclosed is an electrical power supply (18) for use, for example, for a flush fusing device in an electrophotographic recording apparatus, in which a DC high voltage is generated from a low voltage of a AC power supply (11) so that the high voltage DC energy is momentarily consumed or discharged. The electrical power supply (18) is configured in a manner so that, in order to make unnecessary a charging capacitor and a current limiting resistor for preventing rectifier elements from being damaged, at least a part of the rectifier elements are constituted by rectifying control elements such as thyristors or transistors (5, 6) and a control signal is given to those rectifying control elements so as to make the rectifying control elements be in an isolated state. By use of such a configuration, the electrical power supply (18) can be reduced in size as well as in power loss. The effect can be fully exhibited not only in a fusing apparatus employing the electrical power supply but in a recording apparatus employing such a fusing apparatus.