摘要:
A single pass highlight color printer is disclosed which utilizes two pairs of Raster Output Scan (ROS) systems mounted symmetrically about a common polygon motor assembly. Four identical optical systems are thus provided, 180.degree. apart with diode laser outputs directed from a ROS frame parallel and separated to allow the appropriate spacing for xerographic components situated adjacent the xerographic belt. Each ROS unit includes a 90.degree. mirror pair which is mounted on a roof mirror carriage which in turn is connected to a focus carriage via an adjustable guide system. The interaction between the focus carriage and the roof mirror carriage enables a skew alignment and process (beam steering) adjustment to be accomplished with a high degree of precision.
摘要:
A single pass highlight color printer is disclosed which utilizes two pairs of Raster Output Scan (ROS) systems mounted symmetrically about a common polygon motor assembly. Four identical optical systems are thus provided, 180.degree. apart with diode laser outputs directed from a ROS frame parallel and separated to allow the appropriate spacing for xerographic components situated adjacent the xerographic belt. Each ROS unit includes a 90.degree. mirror pair which is mounted on a roof mirror carriage which in turn is connected to a focus carriage via a flexible guide system. The interaction between the focus carriage and the roof mirror carriage enables a skew alignment and process (beam steering) adjustment to be accomplished with a high degree of precision.
摘要:
A xerographic marking device includes a media transport path and at least one two-color image-on-image (IOI) drum module. Each two-color IOI drum module includes in a process order around a photoreceptor: a) a first charging unit; b) a first exposure unit; c) a first development unit; d) a second charging unit; e) a second exposure unit; and f) a second development unit, wherein the intermediate transfer unit receives a first toned image and a second toned image from the photoreceptor in a single transfer and transfers those toner images to print media to produce a toned image on print media. In various embodiments, the xerographic marking device is modular and includes a common paper transport module having a cavity and a marking engine sized to fit within the cavity.
摘要:
A single pass ROS system provides a plurality of latent images which may subsequently be developed in different colors. The ROS units are initially aligned so that each color image is precisely registered at the same relative position along the exposed area of a photoreceptor belt. The alignment is accomplished by forming a pair of opposed alignment apertures in the surface of the belt and detecting coincidence or lack of coincidence of signals generated by the beginning and end of each scan line. The skew correction is enabled by rotating an optical component in the ROS system to create the required rotation of the projected scan line so as to correct for the detected skew error caused primarily by belt conicity. Once the initial X and Y-axis alignments are complete, subsequent alignment is maintained through subsequent passes by checking the positions of the previously identified pixels as they advance past additional lead edge apertures formed in the process direction along the belt surface.
摘要:
For the enhancement of toner release from an imaging surface on a flexible belt member in an electrophotographic device, a resonator suitable for generating vibratory energy is arranged in line contact with the back side of the belt member, to uniformly apply vibratory energy to the member. The resonator includes a horn divided into a linear array of segments, and an array of vibration producing elements, each coupled to at least one horn segment, and driven with a voltage to produce a high frequency vibratory response. To avoid the problem of roll-off in response that occurs at the outer segments of the array of horn segments, the vibration producing elements coupled to the outer horn segments are driven with a higher voltage than those coupled to horn segments in the central portion of the array.
摘要:
The velocity of a photoreceptor belt is measured by sensing the passing of illuminated slits in the belt, as the belt moves in a process direction. Two linear position sensors are positioned so as to view the passing of the illuminated slits. The sensors are aligned in a staggered configuration so that there is an overlap region. The slits are positioned so that as one slit is moving off of a downstream sensor, a second slit is moving over the upstream sensor. The output from an illuminated sensor is alternately switched to the second sensor. The sensor outputs are differentiated to provide an output signal representing a belt velocity. The velocity is compared to said velocity in the belt drive system and error signals generated to compensate for detected changes in the belt velocity.
摘要:
The actual position and velocity of a photoreceptor belt is accurately measured by sensing the passing of illuminated holes in the belt, as the belt moves in a process direction. A segmented sensor array is positioned so as to view the passing of the illuminated holes. A Gaussian light intensity distribution is sensed by a group of sensor pixels which sense the light during a sampling interval. The array produces an output which is operated upon by a centroid processor to determine the center of moment for each sampled intensity distribution. A prediction is then made for projected position of the belt which is very accurate since the centroid calculation is not effected by noise produced by stray light or poorly defined image edges.
摘要:
An electrophotographic device of the type including a flexible belt charge retentive member, driven along an endless path through a series of processing stations that create a latent image on the charge retentive surface, develop the image with toner, and bring a sheet of paper or other transfer member into intimate contact with the charge retentive surface at a transfer station for electrostatic transfer of toner from the charge retentive surface to the sheet. For the enhancement of toner release from a surface at any of the processing stations, a resonator suitable for generating vibratory energy is arranged in line contact with the back side of the charge retentive surface, to uniformly apply vibratory energy to the charge retentive member. The resonator includes a horn, a continuous support member, and a continuous vibration producing member that drives the horn at a resonant frequency to apply vibratoy energy to the belt. The horn includes a platform or base portion, a horn portion extending therefrom, and having a contacting tip. The horn is segmented, through the contacting tip to the platform portion, into a plurality of elements which each act more or less individually. In alternative embodiments, the vibration producing member that drives the horn, and/or the support member may also be segmented in a corresponding manner.
摘要:
A method and apparatus for transverse registration of image exposures on photoreceptive belts subject to lateral deviation from linear travel in which targets, corresponding in location to the image areas to be exposed, are used for the detection of lateral belt displacement and to control the transverse location of exposure scan. The targets are of a pattern defining a reference line and a line inclined with respect to the direction of belt travel so that the duration of time between passage of the target lines with respect to a spacially fixed sensing axis will vary with lateral displacement of the belt. The targets may assume a variety of specific patterns and the invention is applicable to single and multi-pass image exposure systems as well as to both modulated laser and light emitting diode types of exposure devices.
摘要:
For the enhancement of toner release from an imaging surface on a flexible belt member in an electrophotographic device a resonator suitable for generating vibratory energy is arranged in line contact with the back side of the belt member, to uniformly apply vibratory energy to the member. The resonator includes a horn divided into a linear array of segments, and an array of vibration producing elements, each coupled to at least one horn segment, and driven with a voltage to produce a high frequency vibratory response. To avoid the problem of variations in response that occurs due to varying resonant frequencies of each horn element, the vibration producing elements are driven across a range of frequencies that includes each resonant frequency required, over a relatively short period of time.