Compaq Computer Corporation, Inc.

Compag Computer Corporation

Gopal C Bhagat

Cynthia A Crooks

Michael W Ambrose

Stephan A Mato, Jr

James M Webster

Stephen Mato, Jr

A pointing device according to the present invention includes a trackball embedded in the case of a computer display. The trackball is placed adjacent to the display and the select buttons for the trackball are located on the backside of the display case behind the trackball. The user guides the trackball with his thumb and pushes the select buttons on the backside of the case with his index and middle fingers, allowing the user to operate the pointing device with only one hand. Alternatively, the trackball is embedded in the corner of the keyboard of a desktop system, with the select buttons on the opposite side of the keyboard behind the trackball. With the keyboard standing on legs, the user's fingers can reach the two select buttons opposite the trackball to operating the pointing device.

Pointing device for a portable computer

Pointing devices for a portable computer

An electrophotographic printing system. Negatively charged toner is supplied to the surface of a first roller where the toner electrostatically adheres, either in a uniform layer or a variable layer, to the surface of the first roller. The negatively charged toner electrostatically adhered to the surface of the first roller is then transferred to the photoconductive surface and, from a photoconductive surface, to a sheet of paper positioned in proximity to the photoconductive surface. The apparatus may also include a second roller held at a positive charge relative to the first roller for electrostatically transferring toner from the second roller to the first roller. Alternately, the positive charge on the second roller relative to the first roller may be produced by placing a negative charge on the first roller or by placing a negative charge on the second roller and a more negative charge on the second roller. By placing a negative charge on the second roller, the toner will also be negatively charged before transfer to the first roller. The apparatus is further provided with a housing containing a solid desiccant material that serves to absorb harmful moisture that may be present at times throughout the interior of the apparatus, as a result of changes in relative humidity.

Electrophotographic printing system having a moistureless

An apparatus for positioning a pointing device relative to a computer is either free-standing relative to the computer or releasably attached to the computer by a clamp. Buttons for moving the clamp jaw of the clamp from a home position to an extended position for attaching the attachment housing to the computer itself are ergonomically positioned. A hinge and clutch spring are disposed between the apparatus and the pointing device for unlimited pivotable positioning of the pointing device within a 90.degree. range for selected user positioning.

Apparatus for a computer pointing device

Portable computer with trackball mounted in display section

An apparatus for developing an image on a photoconductive surface. The apparatus includes a roller positioned adjacent to the photoconductive surface. Negatively charged toner is supplied to the surface of the first roller where the toner electrostatically adheres, either in a uniform layer or a variable layer, to the surface of the first roller. The negatively charged toner electrostatically adhered to the surface of the firt roller is then transferred to the photoconductive surface. The apparatus may also include a second roller held at a positive charge relative to the first roller for electrostatically transferring toner from the second roller to the first roller. Alternately, the positive charge on the second roller relative to the first roller may be produced by placing a negative charge on the first roller or by placing a negtive charge on the second roller and a more negative charge on the second roller. By placing a negative charge on the second roller, the toner will also be negatively charged before transfer to the first roller.

Apparatus for developing an image on a photoconductive surface

An electrically biased attracter roller is utilized in an electrophotographic image reproduction machine, in place of a conventional corotron device, to electrically transfer toner from the side of a rotating photoconductor drum onto a side surface of paper stock being operatively fed through the machine. The charged roller is spring-biased into forcible side-to-side engagement with the drum and is frictionally rotated by the drum. The paper stock is fed between the rotating roller and drum and, by a combination of pressure and electrical attractive force, the roller very efficiently transfers toner from the drum to the paper. To further improve the overall effectiveness of the attracter roller, a humidity compensation system is provided and is operative to automatically adjust the bias voltage of the roller, and thus the electrical toner attraction force thereof, in response to sensed humidity variations within the machine housing.

Electrostatic roller transfer of toned images from a photoconductor

A printing machine, such as a copier or a printer, is provided with an electrophotographic engine cartridge including a toner cartridge, a rotatable photoconductor drum, and a specially designed magnetic brush development module. The development module utilizes a rotating magnetic roller, disposed in a developer sump, to transport a toner carrier developer material toward a side surface portion of the rotating drum onto which the toner portion of the transported developer is electrically transferred. The development module is operated in a unique closed loop fashion by the action of a specially designed blade member which strips away the toner-depleted developer from the roller and causes it to enter a recycling well. The depleted developer is transferred from the recycling well into the developer sump wherein it is mixed with toner entering the sump from the toner cartridge, and then re-applied, in the form of reconstituted developer, to the magnetic roller for subsequent toner transfer to the rotating drum. The printing machine is further provided with a housing containing a solid desiccant material that serves to absorb harmful moisture that may be present at times within the machine's internal modules.

Moistureless development cartridge for printers and copiers

An electrophotographic printer develops a toned image directly on a sheet of conventional paper, such as bond paper, without first forming the toned image on a layer of photoconductive material. The sheet of conductive paper is ordinarily electric conductive, owing to its relatively high moisture content. Therefore, prior to positioning the sheet of paper adjacent the layer of photoconductive material, the sheet of paper is first dried by heating to a temperature sufficient to evaporate the moisture content therein to a level of less than 3% by weight of the conventional paper. Once the sheet of conventional paper is dried, it is inserted between a developer and the layer photoconductive material so that toner particles attracted to a latent image on the layer of photoconductive material are intercepted by the dried sheet of conventional paper.

Electrophotographic interposition development with means for removing

A printing machine, such as a copier or a printer, is provided with an electrophotographic engine cartridge including a toner cartridge, a rotatable photoconductor drum, and a specially designed magnetic brush development module. The development module utilizes a rotating magnetic roller, disposed in a developer sump, to transport a toner carrier developer material toward a side surface portion of the rotating drum onto which the toner portion of the transported developer is electrically transferred. The development module is operated in a unique closed loop fashion by the action of a specially designed blade member which strips away the toner-depleted developer from the roller and causes it to enter a recycling well. The depleted developer is transferred from the recycling well into the developer sump wherein it is mixed with toner entering the sump from the toner cartridge, and then re-applied, in the form of reconstituted developer, to the magnetic roller for subsequent toner transfer to the rotating drum.

Closed loop magnetic brush development system

An apparatus is provided that controls the distribution of charge on the surface of a photoreceptor drum in an electrophotographic printer while reducing the ozone output over that of a standard corotron. The apparatus includes an electrically conductive shaft coated with a semiconductive material disposed longitudinally parallel to the photoreceptor drum. The shaft and semiconductive material are biased into contact with the photoreceptor drum via spring mounted bearings. Thus, rotation of the photoreceptor drum drives the shaft and semiconductive material to rotate about its longitudinal axis.

Growing community of inventors

Houston, TX, United States of America

Gopal C Bhagat