Xerox Corporation

David K Shogren

William J Nowak

Edward C Bock

Robert G Zambelli

Edwin Zucker

Daniel W Costanza

Thomas N Taylor

Richard F Lehman

John A Durbin

Thomas J Hammond

James M Casella

John H Hinton

Lawrence J Mason

David N Redden

Igor Podzorov

Larry L Jenkins

William J Cecchi

Courtney D James

Sushant G Gaonkar

A shaft mounting and loading arrangement includes a shaft rotatably mounted within a frame of an imaging machine by a pair of spaced mounting bearings. A belt is entrained on the shaft between the bearings. The belt applies a belt load to the shaft along an axially length thereof. Loading is applied to the shaft at locations axially flanking the bearings to counteract deflection of the shaft caused by the belt load applied by the belt.

Assembly and method for reducing shaft deflection

A split drives system for a printer in which a single drive motor drives a first belt drive system for the image fusing system and a second and separate belt drive system driving the sheet registration system. This split drives system mechanically isolates the second and separate belt drive system from torque fluctuations in the image fusing system via the first belt drive system driving the image fusing system. Also, the split driving system can isolate torque variations in the driving of the print media fuser from the driving of the print media sheet transport.

Xerographic printer split drive system to reduce image smear

The multispeed drive mechanism is a clutchless drive mechanism including a rotatable input shaft and a plurality of input gears of different diameters mounted on the input shaft. A plurality of drive gears of different diameters are rotatably mounted on a support member and each engage one of the plurality of input gears. A driven member is driven at different speeds for the same speed of the input shaft by pivoting the support member about the input shaft and using different input gear/drive gear combinations to provide different gear ratios. The multiple speed drive mechanism is particularly useful for driving the movable platen of a copying apparatus at different speeds for reduction and enlargement copying.

Multispeed drive mechanism

A Raster Output Scanner (ROS) assembly is mounted within a printing machine frame so as to maintain a very precise relationship with the photoreceptor being imaged. A ROS housing is mounted in relation to the photoreceptor so that, while the housing is fixed to a machine frame by isolators to damp out vibrations and transients, a mechanical latching to a photoreceptor backer bar provides a degree of rotational movement consistent with movement of the photoreceptor. Thus, errors created by photoreceptor motion are compensated for. The invention discloses a 3 or a 4 point mounting arrangement which affords a high degree of stability coupled with conformance with exacting registration tolerances.

Mounting arrangement for a raster output scanner

A customer replaceable unit includes a cover and support structure for supporting a photoreceptor belt while it is packaged, shipped and inserted over drive and idler rolls in a machine. It prevents a machine operator from having to handle the belt itself and provides protection from extrinsic damage.

Customer replaceable photoreceptor belt module

A tuned vibration absorber is mounted on a motor armature of an AC synchronous motor. The tuned vibration absorber provides an anti-resonance which significantly attenuates the 120 Hz angular velocity pertibation of the AC motor. The tuned vibration absorber has a hub, which attaches to the armature of the AC motor. An inertia ring is connected to the hub via spokes. The spokes and inertia ring provide a torsional resonance to the motor, which attenuates the angular velocity error generated by the AC motor. Due to the reduction in 120 Hz velocity error, the motor can be used in digital printing apparatus with strict motion quality requirements.

Tuned vibration absorbers for AC motors

An optical scanning system is provided which enables a simplex to duplex copying operation without requiring the original documents to be oriented in opposite directions at the exposure station. The invention comprises a first imaging system which accomplished a scan of the first document in a first direction (e.g. left to right). At the end of the first scan of the first document, a second document is scanned in the reverse direction by a second, relay lens system which, in one embodiment, is moved into the optical path to replace the first lens. An optical reversion is thus accomplished which permits the duplex operation to be accomplished and images of the first and second documents to be formed in proper orientation on the output duplex copies.

Optical scanning system for duplex copying

In a full-frame flash electrophotographic printing machine, an imaging system is provided which incorporates a flash lamp directly coupled to an ac line input to enable document exposure. The imaging system also includes a lens whose movement is synchronized with a moving photoreceptor so that an exposure occurs registered at the same image area of the photoreceptor. The invention further includes circuit means for detecting zero crossing points of the line voltage and for generating signals which are used to trigger the lamp into operation at some point during an 8 msec, half cycle of line operation. Further circuit means are provided for controlling exposure levels to conform to detected density of the document being copied. In a second embodiment, the control circuitry is used to couple the ac line into a flash fuser assembly to fuse a transferred image on an output record medium.

Electrophotographic reproduction machine with document exposure system

A scanning system is provided for sequentially scanning both sides of a duplex document and projecting images onto a light sensitive linear array. In a first configuration, the platen and scan/illumination stations are fixed and the document is moved across the platen in a scan and reverse scan direction. The scan/illumination stations are sequentially energized and images of both sides of the document are directed along separate optical paths until they are redirected by a movable mirror assembly into a common lens. In a second configuration, both sides of a duplex document are sequentially scanned by movable scan/illumination stations and directed into a common lens which sequentially projects the document images onto the linear array.

Optical scanning of duplex documents

The invention discloses an imaging system for a reproduction device for reproducing a document at reduced or enlarged magnification, as well as unity magnification. The system includes at least two linear lens arrays, one lens array providing the 1:1 magnification and the second array adapted to provide a reduced or enlarged image depending upon its vertical orientation. Mechanical arrangements are disclosed which translate a magnification selection into the position of the appropriate lens array into the optical path. This positioning includes both horizontal and rotational movement of the lens arrays. A magnification selection also enables a platen (or document) drive system which selects the proper document scanning speed for that magnification. In a disclosed embodiment the linear lens arrays are gradient index lens arrays.

Multi-magnification reproduction device utilizing linear lens assembly

A compact scan document system is enabled by adding motion to the scanning and projection components used in a folded optical system. A general and preferred velocity relationship is set for the system optical elements and a mechanical drive arrangement is disclosed which enable the specific ratios required. In a preferred embodiment, a pulley/belt system is used to provide four velocities such that a document is scanned at a first velocity V, the document image is reflected to a folding mirror arrangement traveling at 0.75 V and projected by a lens moving at a 0.5 V velocity to a photoreceptor image plane via another folding mirror arrangement moving at a 0.25 V ratio.

Compact optical scanning system

An optical scanning system is provided which image-wise exposes a photoreceptor surface at a rate faster than the rate at which the image is scanned. In a preferred embodiment, a dual-rate mirror assembly is driven at a value greater than the process speed of a photoreceptor drum. A movable drum reflector reflects the image in precession fashion along the drum surface in a direction opposite the drum rotation.

Precession scanning system for copier device

A drive for providing a continuous range of magnifications in a copier system. The drive includes a variable speed transmission whose output can be adjusted over a continuous range and then fixed to produce a constant scan rate for transmitting a document image to a photoreceptor. The transmission has two pairs of angled or conical capstans coupled by drive belts or cables whose initial position with respect to the capstans dictate the transmission speed. To change speed the transmission is decoupled from a copier drive motor and one capstan pair is rotated with respect to the second pair. The velocity profile of the rotated pair is thereby charged to produce a desired change in magnification. An alternate embodiment is disclosed wherein a cam and cam following surface in conjunction with a single angled or conical capstan provide the adjustable scanning drive.

Variable speed scanning system

An optical system for a copying device is disclosed which scans a document lying in an object plane by means of a pivoting mirror and projects an image of the document onto the surface of a photoreceptor drum. By rotating the projection lens while simultaneously moving an aperture slit in a direction of movement opposite to the movement of the drum, a condition is constantly maintained wherein the object plane, lens plane and image plane are maintained parallel thereby eliminating field tilt. With this configuration, the image is also precessed onto the drum providing a precession distance which can be used to relax constraints normally imposed by scan return conditions.

Scanning system for copier

The present invention is directed to an object scanning system wherein the illumination scanning means employed travels at a rate which is greater than that of a flat photoreceptor moving in the same direction. In one embodiment, a dual rate mirror assembly scans a document on a platen at a first rate which is greater than the process speed set for a photoreceptor belt. The image is projected through a lens and precessed by a mirror arrangement along the belt surface in a direction opposite to the belt travel. The precession rate can be set relative to the scanning flyback time, so as to reduce or eliminate an interdocument gap on the photoreceptor and to lower process speeds for a given copy rate.

Growing community of inventors

Ontario, NY, United States of America

David K Shogren