Ricoh Company, Ltd.

Ricoh Systems, Inc.

Ricoh Corporation

Forems, Inc.

Edward F Mayer

Donald F Pfeuffer

Carl P Anderson

Victor B Van Blerk

Arthur S Diamond

Paul Chang

William J Murphy

Alan L Koelling

Elden R Morrison

An electrostatic charging system that incorporates a thermally activated glow discharge ion generating technique. An large AC potential is applied between a pair of spaced apart electrodes. A heater disposed near the electrode pair gap is selectively activated to heat the gases in the region of gap to induce ionization. A DC potential applied to a third electrode draws the ionized particles toward a dielectric material to place an electrostatic charge thereon.

Thermally activated electrostatic charging method and system

A sheet feeder is disclosed having a cartridge mounted adjacent the stack of paper providing an exposed line of adhesive strip. The adhesive should be a temporary adhesive which when removed leaves no residue or damage on the sheet to which it was temporarily bonded. The cartridge is landed on the top sheet of paper adjacent the leading edge of the sheet, and the cartridge is then rotated away from the direction in which the sheet is to be fed while maintaining a minimum amount of pressure on the top of the stack. This effectively bonds the gummed strip on the cartridge to the edge of the top sheet of paper; and the motion away from the feeding direction lifts the top edge of the sheet from the edge of the sheet below, which now forms the top of the stack. The sheet below, also to be called the second sheet, remains in place because of the combination of downward pressure against the second sheet near its leading edge created by the cartridge, together with the beam strength of the paper which tends to cause the sheet to continue to lie flat. The cartridge can now be moved in the feeding direction, presenting the sheet of paper to an entry path to the copying machine.

Electrophotographic copying apparatus incorporating an automatic

An arsenic-selenium photoreceptor is provided wherein said photoreceptor is characterized by a gradient concentration of arsenic increasing from the bottom surface to the top surface of the photoreceptor such that the arsenic concentration is about 5 wt. % at a depth of about 5 to 10 microns from the top surface of the photoreceptor and is about 30 to 40 wt. % at the top surface of the photoreceptor.

Gradient layer panchromatic photoreceptor

A document feeder is disclosed wherein a document stack is bent or curved when it rests on a fixed curved stackholding tray. A stack of paper becomes rigid when curved, and therefore, capable of being raised by applying an upward force along the curved edge on each end of the stack provided by a pair of curved lifting blades which move horizontally relative to the ends of the stack to move in and out underneath the edges of the stack, and thereafter move vertically to lift the entire stack out of the path of the returning copy. The document to be copied may be lifted off the top of the document stack either before or after the lifting action of the blades. A vacuum belt type arrangement is provided for moving successive documents from the top of the stack. The document loops through the machine, and returns at a lower level, aligned with an opening beneath the bottom of the stack. A levered plate is provided at the trailing lateral edge of the stack to be sure that the edges of the stack are lifted out of the return paper document path. Moving the belts running beneath the stack carry the returning document into alignment under the stacks; a metal plate running horizontally or laterally along the edge of the stack perpendicular and very close to the belts acts as a stop to stop the returning document in alignment with the document stack being fed. Once the document is returned, the lifting blades move vertically downward, and laterally outward, resting the remainder of the document stack on the returned document and making it a part of the stack.

Recirculating automatic document feeder

A liquid crystal display is provided on the surface of a vidicon face plate. A number of conductive pins or electrodes connect to associated field effect transistors imbedded in the liquid crystal display for selectively energizing discrete areas in the liquid crystal display; the pins extend through the vidicon face plate. The electron beam of the vidicon is scanned sequentially across the terminals, and is turned on and off in accordance with stored binary data to impinge upon and selectively activate certain ones of the pins or electrodes, turning on the associated FET. After the full face of the vidicon has been scanned to form the desired pattern of activated FET's, a voltage is applied across the liquid crystal display. The area opposite each turned on FET will be appropriately polarized presenting a display on the outward facing surface of the display. This display is used to excite a photoconductive drum such as in an electrostatic photocopier to print a copy of the display data.

Character generator using cathode ray tube activated liquid crystal

A cleaning system for an electrophotographic copying apparatus utilizes an electrostatically active belt which is movable relative to the moving surface of the photoconductive drum. As the electrostatic belt moves past the surface, the electrically charged toner is picked up by the belt and carried away from the drum. At a position remote from the drum, the toner is scraped from the belt, preferably to be reused in later cycles of the system. Preferably, the belt is translucent, and a flourescent lamp is mounted behind the belt to discharge the surface of the drum of the remaining latent image as the toner is removed. Typically, the moving belt incorporates an electrostatic grid having alternating charged portions. These charged interleaved portions of the belt attract the electrically charged toner and hold it to the belt as the toner is moved away from the surface of the drum.

Compact cleaning system for electrophotographic copying apparatus

A bottom feeder for copy paper feeding has means for imparting a curvature to the sheets, the curvature being in the direction the sheets will be withdrawn. The curvature provides transverse rigidity to permit lifting weight of stack off the bottom sheet. This facilitates withdrawing the sheets one at a time from the bottom of the stack. A curved paper tray imparts a curvature to the paper. A pair of holding clamps are provided, one on either side of the stack of paper, which are partially withdrawn from the sides of the paper stack so that paper may be added to the stack. When sheets are to be fed, the clamps which comprise a pair of plates having a friction material on the paper facing side thereof are moved in to engage the sides of the stack of paper. An arrangement is provided to thereafter lower the paper tray slightly from the bottom of the stack, or lift the clamps and the curved paper stack. In either event, the pressure of the stack weight is now removed from the bottom sheet. A vacuum type feed belt which passes under the stack of paper can now pick off one sheet at a time without the sheets being restrained by friction against the paper tray or created between the tray and the stack of paper. The friction material on the holding plates in a preferred embodiment comprises bristles angled upward away from the paper tray to retain the stack lifted from the paper tray while allowing relatively easy withdrawal of each sheet. A stack-height sensor, preferably a switch on the face of one of the plates, senses the condition where, as the height of the stack diminishes, the pressure of the holding clamp plates may be slightly reduced to avoid binding of the paper. Timing means, which in the disclosed embodiment comprise cams riding on a common shaft, are provided to coordinate the movement of the clamps toward and away from the sides of the stack with the movement of the paper tray away from the bottom of the stack of paper.

Copying apparatus with automatic bottom feeder

A thermally responsive shutter interrupts or transmits light through an optical fiber. A small heater, such as a resistance heater, is positioned centrally under a gap in an optical fiber. At one end of the fiber is an illumination source; the opposite end of the fiber is the output end. The gap between the two segments of the optical fiber is filled by an opaque dye solution comprising a volatile organic or other liquid, and a high opacity dye. In the normal state, the dye solution interrupts the light passing through the glass fiber. Upon activation of the heater, the gap is sufficiently small that a bubble will form between the ends of the glass fibers. This removes substantially all of the dye from the gap between the fibers, and permits light to pass from the light source to the output end of the optical fiber.

Fiber optic high speed pulse scanner

A storage assembly for trailer hitch torsion bars mounted on the trailer tongue having a pocket for receiving the greased tip of the torsion bar and a bracket for supporting the bar in the pocket.

Storage assembly for trailer hitch torsion bars

An ink liquid supply apparatus is provided for an ink jet printing apparatus which maintains the concentration of ink in the system at a constant value and allows utilization of an ink which contains a non-water soluble dye, resulting in a more permanent, quicker drying ink. The ink liquid supply apparatus functions to maintain the ink concentration constant by utilizing an ink emulsion which is in complete equilibrium with a hydrocarbon liquid and a water supply.

Ink liquid supply apparatus

A particle cleaning blade is mounted to cause the edge of the cleaning blade to describe an arc having both radial and axial components relative to the drum surface so that at its lowest point the blade comes into contact with the surface of the photoconductive drum. The mounting incorporates sufficient mechanical tolerances in the mechanical components to cause the final position of the blade relative to the surface of the drum to shift slightly from one wiping sequence to the next; any defects in the blade are shifted laterally across the drum. The mounting is a parallelogram type arrangement, which is spring-biased to hold the blade in a position removed from the surface of the drum by rotating the sides away from the vertical. A solenoid actuator is provided, located laterally with respect to the parallelogram and near one upright side. When the solenoid is actuated, it overcomes the biasing spring force, and draws the arms upright by overcoming the spring biasing force. The mounting which supports the parallelogram ideally also incorporates a scraper blade made of a flexible sheet of material held against the side of the cleaner blade.

Electrophotographic copying apparatus including a guillotine cleaner

An electrophotographic copying apparatus utilizing a rotatable drum having a photosensitive outer circumferential surface is disclosed herein along with its method of operation. In making copies of a given sheet of information, an electrostatic latent image corresponding to the information to be copied is formed on a circumferential segment of the drum surface and the image is developed by applying toner onto the image bearing segment of the drum surface. Thereafter, the applied toner is transferred to a blank sheet thereby forming the copy. Once one or more copies are made from a given electrostatic image, any applied but untransferred toner on the drum surface is moved onto a second circumferential segment, preferably by means of a pliant roller segment and preferably with the aid of electrostatic attraction. The toner accumulated on the second segment of the drum surface is then moved by the latter to a specific point and removed from the second surface segment. During this latter movement, the toner is electrostatically held in place on the second drum surface segment.

Electrophotographic copying apparatus and method of use including

There is disclosed herein an electrophotographic copying apparatus and its method of operation in which electrically charged toner of one polarity is transferred from an oppositely charged electrostatic image on the outer surface of its photoconductive drum to the front side of a blank sheet for transforming the latter into an intended copy as the back side of the blank sheet engages the outer surface of a transfer roll positioned adjacent the drum. In accordance with one feature of this apparatus, both the front side of the blank sheet, before it receives toner, and the outer surface of the transfer roll are biased such that each carries the same charge as the drum surface and such that the combined voltage level of both is greater than the voltage level of the electrostatic image. In accordance with another feature, the biasing means is designed for changing this combined voltage level in a way which improves the transferring capability of the apparatus, especially when more than one copy is made from a single electrostatic image.

Electrophotographic copying apparatus including electrically biased

An assembly for developing a latent electrostatic image formed on the photosensitive outer surface of a rotating developing drum making up a part of an electrophotographic copying apparatus is disclosed herein. This assembly includes a supply of developer contained within a housing adjacent the drum, a primary magnetic brush within the housing for continuously moving fresh developer in close proximity with the drums photosensitive outer surface, and an arrangement including a series of rollers acting on the developer leaving the primary brush for enhancing the developing process.

Electrophotographic copying apparatus including an enlarged image

An assembly for developing a latent electrostatic image formed on the photosensitive outer surface of a rotating developing drum making up a part of an electrophotographic copying apparatus is disclosed herein. This assembly includes a supply of developer contained within a housing adjacent the drum, a series of electrodes acting on the developer to aid in developing the electrostatic image, and an arrangement cooperating with the electrodes for cleaning the latter of developer deposited thereon during the development process.

Growing community of inventors

San Jose, CA, United States of America

Edward F Mayer