Canon Kabushiki Kaisha

Other

Osamu Nagasaki

Hiroshi Mano

Atsuhiko Yamaguchi

Kouji Yasukawa

Masamichi Iida

Naoki Nishimura

Masahiro Suzuki

Tomohiro Nakamori

Kazushi Ino

Teruhiko Namiki

Takuya Mukaibara

Takashi Fukuhara

Tohru Saito

Takehiro Uchiyama

Hiroki Murata

Koichi Suzuki

Masafumi Monde

Go Araki

Seiji Yokoyama

Hidenori Kanazawa

Yuki Sugiyama

Jun Haruna

A piezoelectric transformer includes a piezoelectric element. Two primary side electrodes exist on the primary side of the piezoelectric element. The primary side electrodes are coupled by a resistor formed from a conductive coating. A discharge current is discharged via the resistor to protect a semiconductor component from the discharge current. Since neither a short-circuit terminal nor conductive jig is required, electrostatic discharge damage to a semiconductor component can be prevented by a low-cost arrangement.

Printed circuit board, power supply apparatus, image forming apparatus, and printed circuit board manufacturing method

A toner detection unit is configured by an LED that irradiates light toward an intermediate transfer belt, first and second light receiving elements that respectively receive specular reflection light and diffused reflection light of light irradiated toward the intermediate transfer belt from the LED, a circuit board, and a housing. The LED and the light receiving elements are mounted in a line on the circuit board. The housing is configured to guide, to the first light receiving element, the specular reflection light from a first region within an irradiation region on which light is irradiated from the LED on the intermediate transfer belt, and to guide, to the second light receiving element, the diffused reflection light from a second region which is different from the first region within the irradiation region.

Optical sensor and image forming apparatus

A scanning unit performs scanning over a photosensitive member with a laser beam irradiated from a light source. A width correction unit corrects exposure time. A luminance correction unit corrects luminance of the laser beam for forming latent images. A density correction unit corrects a density value of each of the pixels of the image data according to a scanning position of the laser beam on the surface of the photosensitive member.

Image forming apparatus that forms latent image by irradiating photosensitive member with light

A negative bias circuit outputs a DC voltage of a negative polarity. A positive bias circuit outputs a DC voltage of a positive polarity. The DC voltage of the positive polarity is used, for example, as a transfer voltage, and the DC voltage of the negative polarity is used as a cleaning voltage for cleaning toner. A cycle of the clock signal in a period during which the DC voltage of the first polarity is output is longer than a cycle of the clock signal in the period during which the voltage supplied to the load transits from the DC voltage of the first polarity to the DC voltage of the first polarity.

Voltage generating apparatus for stably controlling voltage

An image-forming apparatus includes: an image forming unit which forms an unfixed toner image on a recording material; a fixing unit having a heat generating member which generates heat by power supplied from a commercial AC power source via a choke coil, the fixing unit heating the unfixed toner image formed by the image forming unit and thereby fixing the image to the recording material; and a control unit which controls the supply of power from the commercial AC power source to the heat generating member. The control unit supplies power to the heat generating member by control including phase control, during printing for performing an image forming operation by the image forming unit, and supplies power to the heat generating member by wave number control during standby for awaiting a print instruction.

Image-forming apparatus supplying power to heat generating member using phase control and/or wave number control

An image forming apparatus having a stapler includes an image forming unit configured to form an image on a recording material, a power source configured to supply electric power to the image forming unit and the stapler, and a control unit configured to control the operation of the stapler. In the image forming apparatus, a time period for prohibiting the operation of the stapler is set such that a total of a power consumption of the image forming unit and a power consumption of the stapler is equal to or less than an electric power the power source can supply so as to perform the operation of the stapler and the operation of the image forming unit partially in parallel with each other.

Image forming apparatus and stapler

A high-voltage power supply comprises the following components. A piezoelectric transformer outputs a voltage in accordance with a supplied drive frequency. A rectification part is connected to an output side of the piezoelectric transformer. A drive frequency generating part generates the drive frequency supplied to the piezoelectric transformer. A voltage detection part detects an output voltage of the piezoelectric transformer or the rectification part. A control part controls the drive frequency generating part such that a drive frequency corresponding to the output voltage detected by the voltage detecting part is generated. A first time constant, which is a time constant of the control part, is smaller than a second time constant, which is a time constant of a control target including the piezoelectric transformer and the rectification part. A third time constant, which is a time constant of the voltage detecting part, is smaller than the second time constant.

Technology for reducing circuit oscillations and ripple in a high-voltage power supply using a piezoelectric transformer

The voltage at a spurious frequency is decreased while maintaining as much as possible the voltage at a resonance frequency of a piezoelectric transformer, thus controlling a wide voltage range with a comparatively low cost configuration. A high-voltage power supply apparatus includes a piezoelectric transformer that outputs a highest voltage at a predetermined resonance frequency, and a generating unit that generates a signal that oscillates at a drive frequency that drives the piezoelectric transformer, throughout a frequency range that includes the resonance frequency. Furthermore, the high-voltage power supply apparatus includes an output terminal connected to the piezoelectric transformer, and a constant-voltage element inserted in a path that couples the piezoelectric transformer and the output terminal.

High-voltage power supply apparatus and image forming apparatus employing same

A high voltage power supply includes a frequency signal generation unit, a voltage generation unit, and a voltage amplifying unit. The frequency signal generation unit generates a frequency signal. The voltage generation unit generates an input voltage according to the frequency signal generated by the frequency signal generation unit. The voltage amplifying unit amplifies and outputs the input voltage by rectifying and smoothing the input voltage a plurality of times. A voltage output by the voltage amplifying unit is changed by changing a frequency of the frequency signal.

High voltage power supply

An electronic apparatus includes, for example, a circuit board with an electronic component and a piezoelectric element, a reference potential pattern that gives a reference potential to at least one of the electronic component and the piezoelectric element, and a solder land connected to the reference potential pattern. On the circuit board, the electronic component is located on a downstream side in a transport direction of the circuit board during mounting of the piezoelectric element and the electronic component on the solder land, and the piezoelectric element is located on an upstream side in the transport direction.

Printed circuit board equipped with piezoelectric element

A high voltage power supply may include a switching unit, a voltage resonant unit, a connection part, a rectifier unit, a voltage amplifying unit, a voltage output unit, and a frequency control unit. The switching unit is driven per a frequency signal. The voltage resonant unit is connected to the switching unit and includes an inductor, to which a voltage is applied, and a capacitor. The connection part connects the switching unit and the inductor. The rectifier unit includes a diode that is connected to a power-supply voltage side of the inductor via a capacitor. The voltage output unit outputs a voltage obtained from the voltage amplifying unit. Moreover, the frequency control unit controls a frequency of the frequency signal per a control signal used to set a voltage output from the voltage output unit and an output signal output from the voltage output unit.

A power supply device generates an output voltage by driving a piezoelectric transformer using a frequency signal. The power supply device includes a comparison unit configured to compare an output voltage and a voltage setting signal that sets the output voltage, and a voltage control oscillation unit configured to generate the frequency signal to drive the piezoelectric transformer based on comparison results of the comparison unit. The voltage control oscillation unit generates the frequency signal within a range between the resonant frequency and a spurious resonant frequency closest to the resonant frequency.

Growing community of inventors

Numazu, Japan

Osamu Nagasaki