Actuator for actuating a surface contacting probe of a contacting electrostatic voltmeter
AssigneeXerox Corporation
InventorsWilbur M. Peck, Stanley J. Wallace, Alan J. Werner, Jr.
Life of this patent
Estimating the term…
Abstract
A contacting electrostatic voltmeter suitable for sampling positive or negative potentials on an electrostatically charged surface. The electrostatic voltmeter includes a selectively controllable actuation mechanism that enables the use of a contacting electrostatic voltmeter to sample the surface of an electrostatically charged member, moving relative thereto, within a predetermined space. The invention finds particular use in a printing system, where it enables charge monitoring during printing yet avoids disturbance to charged latent image areas on the imaging member.
Claims16
An apparatus for sensing an electrostatic potential on a surface and generating a signal representative thereof for input to an electrostatic voltmeter, comprising:
- an electroconductive brush formed of a plurality of conductive fibers;
- a brush support member supporting a first end of the conductive brush fibers;
- an electrical conductor, connected between the first end of the conductive brush fibers and the electrostatic voltmeter;
- and
- actuating means, associated with said brush support member, for selectively moving said electroconductive brush into and out of contact with the surface.
An electrostatic voltmeter apparatus for measuring an electrostatic potential on a surface, comprising:
- a surface contacting sensor for producing an output signal representative of the electrostatic potential on the surface, including an electroconductive brush and actuating means associated with said brush, wherein the actuating means selectively moves said brush into and out of contact with the surface;
- a high-voltage source, said high-voltage source producing a first potential having a polarity the same as the electrostatic potential and a magnitude greater than that of the electrostatic potential;
- level shifting means, powered by said high-voltage source, for shifting a level of the output signal produced by said surface contacting sensor, so as to reference the output signal to a ground potential, and generating a first signal in response to the ground potential referenced output signal;
- and
- means, connected to receive the first signal from said level shifting means, for converting the first signal to a low voltage signal, wherein the low voltage signal is referenced to ground potential and where a magnitude of a deviation of the low voltage signal from ground potential is a measure of the electrostatic potential.
A xerographic printing machine comprising:
- a photosensitive member including a surface thereof rotating in a first direction through
- a charging station for depositing an electrostatic potential thereon,
- an imaging station for selectively exposing regions of the surface to produce latent electrostatic images thereon, where the latent electrostatic images are separated by an interdocument space,
- a developer station for depositing a marking material on the latent electrostatic image,
- a transfer station for transferring the deposited marking material to a substrate, and
- a cleaning station for removing marking material remaining on the surface after transfer;
- and
- an electrostatic voltmeter, disposed at a location adjacent the surface of the photosensitive member subsequent to the imaging station along the first direction of rotation of the photosensitive member, for sensing an electrostatic potential on a surface and generating a signal representative thereof for input to the electrostatic voltmeter, including
- an electroconductive brush formed of a plurality of conductive fibers,
- a brush support member for supporting a first end of the conductive brush fibers,
- an electrical conductor, connected between the first end of the conductive brush fibers and the electrostatic voltmeter, and
- actuating means, associated with said brush support member, for selectively moving said electroconductive brush into and out of contact with the surface.
Dependencies are inferred from the claim text.