Abstract: A two-stage AC-DC power converter for powering a load at a substantially constant current, and related methods and systems. The first stage of the AC-DC power converter includes a conventional power factor correction (PFC) circuit that outputs a direct current (DC) voltage and a DC current. The second stage of the AC-DC power converter includes a low voltage flyback circuit that receives the DC voltage and the DC current. The low voltage flyback circuit includes a flyback transformer and a switch circuit that selectably toggles the substantially constant output current provided by the low voltage flyback circuit to the load between a first and a second, preset constant current. The secondary windings of the flyback transformer are split into two sections, and the switch circuit toggles the two sections of the secondary windings between a series and a parallel configuration to provide the first and second, preset constant currents.

Abstract: A two-stage LED driver for providing a substantially constant output current to an LED load, and related methods and systems. The first stage of the LED driver includes a conventional power factor correction (PFC) circuit that outputs a direct current (DC) voltage and a DC current. The second stage of the LED driver includes a low voltage flyback circuit that receives the DC voltage and the DC current. The low voltage flyback circuit includes a flyback transformer and a switch circuit that selectably toggles the substantially constant output current provided by the low voltage flyback circuit to the LED load between a first and a second, preset constant current. The secondary windings of the flyback transformer are split into two sections, and the switch circuit toggles the two sections of the secondary windings between a series and a parallel configuration to provide the first and second, preset constant currents.

Abstract: A single-stage AC-DC power converter for powering a load at a substantially constant current, and related methods and systems. The AC-DC power converter includes a high power factor correction (PFC) circuit configured in a flyback topology and operating in transition mode. The flyback PFC circuit has a PFC controller and is configured to draw an input AC current from an AC power supply. The input AC current has a first total harmonic distortion (THD). The flyback PFC circuit outputs a DC current to the load. The PFC controller is configured to sense a rectified input voltage. By multiplying the rectified input voltage sensed by the PFC controller, the input AC current drawn by the flyback PFC circuit has a second, much improved THD, which is achievable without the need of an expensive PFC controller. The rectified input voltage sensed by the PFC controller is multiplied using a Zener diode ladder.

Abstract: A single-stage AC-DC power converter for powering a load at a substantially constant current, and related methods and systems. The AC-DC power converter includes a high power factor correction (PFC) circuit configured in a flyback topology and operating in transition mode. The flyback PFC circuit outputs a direct current (DC) voltage and a DC current. The PFC circuit further includes a flyback transformer and a switch circuit that selectably toggles the substantially constant output current provided to the load between a first and a second, preset constant current. The secondary windings of the flyback transformer are split into two sections, and the switch circuit toggles the two sections of the secondary windings between a series and a parallel configuration to provide the first and second, preset constant currents. The switch circuit includes a switch and three, fast Schottky diodes.

Abstract: A single-stage AC-DC power converter for powering a load at a substantially constant current, and related methods and systems. The AC-DC power converter includes a high power factor correction (PFC) circuit configured in a flyback topology and operating in transition mode. The flyback PFC circuit has a PFC controller and is configured to draw an input AC current from an AC power supply. The input AC current has a first total harmonic distortion (THD). The flyback PFC circuit outputs a DC current to the load. The PFC controller is configured to sense a rectified input voltage. By multiplying the rectified input voltage sensed by the PFC controller, the input AC current drawn by the flyback PFC circuit has a second, much improved THD, which is achievable without the need of an expensive PFC controller. The rectified input voltage sensed by the PFC controller is multiplied using a Zener diode ladder.

Abstract: A two-stage LED driver for providing a substantially constant output current to an LED load, and related methods and systems. The first stage of the LED driver includes a conventional power factor correction (PFC) circuit that outputs a direct current (DC) voltage and a DC current. The second stage of the LED driver includes a low voltage flyback circuit that receives the DC voltage and the DC current. The low voltage flyback circuit includes a flyback transformer and a switch circuit that selectably toggles the substantially constant output current provided by the low voltage flyback circuit to the LED load between a first and a second, preset constant current. The secondary windings of the flyback transformer are split into two sections, and the switch circuit toggles the two sections of the secondary windings between a series and a parallel configuration to provide the first and second, preset constant currents.

Abstract: A two-stage AC-DC power converter for powering a load at a substantially constant current, and related methods and systems. The first stage of the AC-DC power converter includes a conventional power factor correction (PFC) circuit that outputs a direct current (DC) voltage and a DC current. The second stage of the AC-DC power converter includes a low voltage flyback circuit that receives the DC voltage and the DC current. The low voltage flyback circuit includes a flyback transformer and a switch circuit that selectably toggles the substantially constant output current provided by the low voltage flyback circuit to the load between a first and a second, preset constant current. The secondary windings of the flyback transformer are split into two sections, and the switch circuit toggles the two sections of the secondary windings between a series and a parallel configuration to provide the first and second, preset constant currents.

Abstract: A two-stage light emitting diode (LED) driver for powering an LED load at a substantially constant current, and related methods and systems. The first or front end stage of the LED driver includes a buck topology power factor correction (PFC) circuit, the buck PFC circuit and a PFC controller. The second stage of the LED driver includes a conventional isolation and regulator circuit configured to receive the DC voltage and DC current output by the buck PFC and then to provide the substantially constant current to the LED load. By multiplying the rectified input voltage sensed by the PFC controller, the input AC current drawn by the buck PFC circuit has a much improved total harmonic distortion (THD), which is achievable without the need for using an expensive PFC controller. The rectified input voltage is multiplied using a Zener diode ladder.

Abstract: A two-stage AC-DC power converter for powering a load at a substantially constant current, and related methods and systems. The first or front end stage of the AC-DC power converter includes a buck topology power factor correction (PFC) circuit and a PFC controller. The second stage of the AC-DC power converter includes a conventional isolation and regulator circuit configured to receive the DC voltage and DC current output by the buck PFC and then to provide the substantially constant current to the load. By multiplying the rectified input voltage sensed by the PFC controller, the input AC current drawn by the buck PFC circuit has a much improved total harmonic distortion (THD), which is achievable without the need for using an expensive PFC controller. The rectified input voltage sensed by the PFC controller is multiplied using a Zener diode ladder.

Abstract: Exemplary embodiments provide intermediate transfer members that can be used in electrostatographic devices and methods for using them in forming an image. The disclosed intermediate transfer members can include a plurality of nanotubes with high electrical conductivity, high thermal conductivity, and/or low humidity sensitivity. The hydrophobicity of the nanotubes can be controlled by covalently grafting hydrophobic components onto one or more nanotubes; surface treating one or more nanotubes; and encapsulating one or more nanotubes with hydrophobic components. In an exemplary embodiment, the nanotubes can be dispersed in polymer matrices and/or formed on the surface of polymer matrices of the intermediate transfer members. The intermediate transfer members can take various forms of belts, sheets, webs, films, rolls, tubes or any shape that can provide a smooth surface and rotatable function.

Abstract: A two-stage light emitting diode (LED) driver for powering an LED load at a substantially constant current, and related methods and systems. The first or front end stage of the LED driver includes a buck topology power factor correction (PFC) circuit, the buck PFC circuit and a PFC controller. The second stage of the LED driver includes a conventional isolation and regulator circuit configured to receive the DC voltage and DC current output by the buck PFC and then to provide the substantially constant current to the LED load. By squaring the rectified input voltage sensed by the PFC controller, the input AC current drawn by the buck PFC circuit has a much improved total harmonic distortion (THD), which is achievable without the need for using an expensive PFC controller. The rectified input voltage is squared using a Zener diode ladder circuit.

Abstract: An electrophotographic imaging device includes a charging device, a cleaning device, and a fuser member that each include hydrophobic carbon nanotubes. The use of hydrophobic carbon nanotubes can increases the charging device's, the cleaning device's, and the fuser member's durability, conductivity, and contaminants deposition.

Abstract: An electrophotographic imaging device includes a charging device, a cleaning device, and a fuser member that each include hydrophobic carbon nanotubes. The use of hydrophobic carbon nanotubes can increases the charging device's, the cleaning device's, and the fuser member's durability, conductivity, and contaminants deposition.

Abstract: A binder containing a substituted fluorone can be utilized in an electrophotographic imaging member undercoat layer.

Abstract: Processes for making organic photosensitive pigments for charge generating layers of imaging members. The pigments may include titanyl phthalocyanine. The pigments may be synthesized through a partially electrochemical or purely electrochemical process. The pigments may be used in a charge generating layer of an imaging member having a substrate, the charge generating layer, and a charge transfer layer.

Abstract: The presently disclosed embodiments relate in general to electrophotographic imaging members, such as layered photoreceptor structures, and processes for making and using the same. More particularly, the embodiments pertain to a photoreceptor undercoat layer that includes polyol and aminoplast resins to improve image quality.

Abstract: An electrophotographic imaging device includes a charging device, a cleaning device, and a fuser member that each include hydrophobic carbon nanotubes. The use of hydrophobic carbon nanotubes can increases the charging device's, the cleaning device's, and the fuser member's durability, conductivity, and contaminants deposition.

Abstract: Exemplary embodiments provide intermediate transfer members that can be used in electrostatographic devices and methods for using them in forming an image. The disclosed intermediate transfer members can include a plurality of nanotubes with high electrical conductivity, high thermal conductivity, and/or low humidity sensitivity. The hydrophobicity of the nanotubes can be controlled by covalently grafting hydrophobic components onto one or more nanotubes; surface treating one or more nanotubes; and encapsulating one or more nanotubes with hydrophobic components. In an exemplary embodiment, the nanotubes can be dispersed in polymer matrices and/or formed on the surface of polymer matrices of the intermediate transfer members. The intermediate transfer members can take various forms of belts, sheets, webs, films, rolls, tubes or any shape that can provide a smooth surface and rotatable function.

Abstract: Processes for making organic photosensitive pigments for charge generating layers of imaging members. The pigments may include titanyl phthalocyanine. The pigments may be synthesized through a partially electrochemical or purely electrochemical process. The pigments may be used in a charge generating layer of an imaging member having a substrate, the charge generating layer, and a charge transfer layer.

Abstract: Use of pigments for charge generating layers of imaging members. The pigments may include methoxygallium phthalocyanine. The pigments may have a sensitivity of between about 260 and about 290, and may include methoxygallium phthalocyanine that has been converted. The pigments may be used in a charge generating layer of an imaging member having a substrate, the charge generating layer, and a charge transfer layer.