Abstract: Disclosed is a toroidal line filter with coils wound through various winding processes such that an inductance characteristic for a certain frequency can be improved through changes in current flowing direction and/or area, whereby the toroidal line filter can compensate for a poor EMI characteristic at the certain frequency without adding extra components such as an inductor or a capacitor. The toroidal line filter comprises an annular core and coils wound around the annular core. The coils are wound in such a way that first winding is wound over a predetermined partial area of the annular core, which is not the entire area of the annular core, and then second winding is wound over the remaining area of the annular core.

Abstract: A high voltage power supply (HVPS) including first and second high voltage output controllers controlling output of a high voltage output signal; and a plurality of transformers transforming an output signal provided from the first and second high voltage output controller, disposed outside of the first and second high voltage controllers on the substrate, wherein output terminals in the secondary sides of the plurality of transformers are disposed along the edge of the substrate. Therefore, the volume of a system can be minimized by arranging circuits in each component for high voltage output in parallel, and spark and discharge can be reduced by minimizing interference between the primary sides and the secondary sides of the components for high voltage output, thereby preventing damage to a product.

Abstract: A high voltage power controlling apparatus of an image forming apparatus including a DC (direct current) power controller to convert and output a first PWM (pulse width modulation) signal provided from an engine controller into a switching waveform signal, a first voltage transformer to transform the switching waveform signal output from the DC power controller, a rectifier to rectify output power transformed by the first voltage transformer into DC power, first through N (where N is a positive integer greater than one) DC supplies to adjust and output the DC power rectified by the rectifier such that the DC power is adjusted to a predetermined level, first through N AC (alternating current) power controllers to convert and output a second PWM signal provided from the engine controller into switching waveform signals, and second through N+1 voltage transformer to transform the switching waveform signals output from the first through N AC power controllers, to overlap the transformed powers with the DC powers

Abstract: An AC high voltage detecting device includes a high voltage power supply (HVPS) to convert a low voltage into an AC high voltage, a rectifier to rectify the converted AC high voltage into a positive voltage and a negative voltage, a voltage divider to divide the rectified positive voltage and the rectified negative voltage into a first voltage and a second voltage, respectively; and a detector to read out a sum component of the first and the second voltages to detect the AC high voltage in a DC level. Since the AC high voltage supplied from the high voltage power supply is detected after being converted into a DC voltage, there is no variance caused due to various devices required to detect an AC voltage.

Abstract: Provided is a high voltage power supply which includes a controller to provide a PWM signal and a power signal, an input unit to receive the PWM signal provided from the controller, a comparison unit to control output of the power signal supplied from the controller by comparing a signal filtered to a DC voltage by the input unit to a voltage reference signal, a transformation unit to transform the power signal output from the comparison unit, and a rectification unit to rectify the signal output by the transformation unit, wherein the high voltage power supply further includes a power input delay unit to delay the supply of the power signal to the comparison unit by a predetermined time from when the power supplied from the controller for input into the comparison unit.

Abstract: A fusing system and a fusing control method of an image forming apparatus includes a sensor which senses whether a skew of a paper is generated, wherein the skew refers to the paper being obliquely fed along a paper feeding path, a fusing unit which fuses a developer transferred on the paper, and a controller, if it is sensed that the skew is generated, which controls fusing operations of the fusing unit not to performed. The heater lamp is controlled depending on whether a paper skew is generated while the paper is fed so that power and toner waste can be reduced for a paper that loses the value of printing result.

Abstract: A high voltage power supply (HVPS) with digital control and a method of generating high voltage. The HVPS may include switching units to intermit a current flowing in a primary side coil of a transformer and to control a voltage induced into a secondary side coil of the transformer, digital control units to control the intermission of the switching units in response to an input control data, and a digital interface unit to provide the digital control units with the control data extracted from a control code that is transferred according to a predetermined communication protocol. Because the number of parts used for the HVPS is reduced, a printed circuit board space is used more efficiently and an overall process yield is increased.

Abstract: An AC high voltage detecting device includes a high voltage power supply (HVPS) to convert a low voltage into an AC high voltage, a rectifier to rectify the converted AC high voltage into a positive voltage and a negative voltage, a voltage divider to divide the rectified positive voltage and the rectified negative voltage into a first voltage and a second voltage, respectively; and a detector to read out a sum component of the first and the second voltages to detect the AC high voltage in a DC level. Since the AC high voltage supplied from the high voltage power supply is detected after being converted into a DC voltage, there is no variance caused due to various devices required to detect an AC voltage.

Abstract: An image forming device has a developing process part comprising a plurality of developing process rollers, and a delivery part to move a printing paper to pass through the developing process part. The image forming device includes a skew sensor to detect a skew degree of the printing paper supplied to the developing process part by the delivery part, a potential forming part to form predetermined potential differences among the plurality of developing process rollers to make a developer be applied on the printing paper, and a controller to prevent the potential forming part from forming the predetermined potential differences on the plurality of process developing rollers when the skew degree of the printing paper deviates from a predetermined allowance range. Thus, the image forming device prevents an image from being formed when the skew degree of the printing paper deviates from the predetermined allowance range.

Abstract: An apparatus to generate a high voltage includes a switching part to control a voltage induced in a secondary coil of a power transforming part, by interrupting a current in a primary coil of the power transforming part, a digital controlling part to control the interruption operation of the switching part according to supplied control data. The switching part, the digital interfacing part and the digital controlling part may be embodied in an ASIC chip (application-specific integrated circuit). An optimum control according to an output state of the apparatus is easily achieved, manufacturing time for tuning each parameter is reduced and heat generation in the apparatus is reduced.

Abstract: An analog control application specific integrated circuit (ASIC) apparatus for a high voltage power supply (HVPS) in an image for apparatus, and a method for controlling the HVPS are provided. The HVPS includes a transformer transforming an AC signal to a high voltage signal and a voltage doubler outputting a DC high voltage for the HVPS. The ASIC includes an analog control circuit configured as a one-chip ASIC that converts a predetermined DC level signal to a high frequency switching signal using a switching component and outputs the converted high frequency switching signal to a primary winding of the transformer. If the high voltage output signal output from the voltage doubler is not feedbacked, the switching component high frequency switches a received driving signal of a gate driver, and outputs the high frequency switched signal to the transformer.

Abstract: Disclosed is a high-voltage generator and method of controlling high voltage. The high-voltage generator includes: a power-supplying unit for rectifying an AC power supplied from the outside and generating a first and a second DC powers; a controlling unit to generate PWM (Pulse Width Modulated) signal with a predetermined duty-ratio when the first DC power is supplied; a comparing unit to compare the PWM (Pulse Width Modulated) signal and a predetermined reference voltage and to output a driving signal; a high-voltage generating unit to boost the second DC power by switching operation according to the driving signal and to generate high voltage; and a load sensing unit to sense a load supplied to an output end of the high-voltage generating unit. The controlling unit prevents a generation of high-voltage when the load is equal to, or less than a predetermined reference value.

Abstract: Disclosed is a toroidal line filter with coils wound through various winding processes such that an inductance characteristic for a certain frequency can be improved through changes in current flowing direction and/or area, whereby the toroidal line filter can compensate for a poor EMI characteristic at the certain frequency without adding extra components such as an inductor or a capacitor. The toroidal line filter comprises an annular core and coils wound around the annular core. The coils are wound in such a way that first winding is wound over a predetermined partial area of the annular core, which is not the entire area of the annular core, and then second winding is wound over the remaining area of the annular core.